SQLite

         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo journal.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.lo \
         memjournal.lo \
         mutex.lo mutex_noop.lo mutex_os2.lo mutex_unix.lo mutex_w32.lo \
         notify.lo opcodes.lo os.lo os_os2.lo os_unix.lo os_win.lo \
         pager.lo parse.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo select.lo status.lo \
         table.lo tokenize.lo trigger.lo \
         update.lo util.lo vacuum.lo \
         vdbe.lo vdbeapi.lo vdbeaux.lo vdbeblob.lo vdbemem.lo vdbesort.lo \
         vdbetrace.lo wal.lo walker.lo where.lo utf.lo vtab.lo

  $(TOP)/src/mem2.c \
  $(TOP)/src/mem3.c \
  $(TOP)/src/mem5.c \
  $(TOP)/src/memjournal.c \
  $(TOP)/src/mutex.c \
  $(TOP)/src/mutex.h \
  $(TOP)/src/mutex_noop.c \
  $(TOP)/src/mutex_os2.c \
  $(TOP)/src/mutex_unix.c \
  $(TOP)/src/mutex_w32.c \
  $(TOP)/src/notify.c \
  $(TOP)/src/os.c \
  $(TOP)/src/os.h \
  $(TOP)/src/os_common.h \
  $(TOP)/src/os_os2.c \
  $(TOP)/src/os_unix.c \
  $(TOP)/src/os_win.c \
  $(TOP)/src/pager.c \
  $(TOP)/src/pager.h \
  $(TOP)/src/parse.y \
  $(TOP)/src/pcache.c \
  $(TOP)/src/pcache.h \

  $(TOP)/src/date.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/insert.c \
  $(TOP)/src/wal.c \
  $(TOP)/src/mem5.c \
  $(TOP)/src/os.c \
  $(TOP)/src/os_os2.c \
  $(TOP)/src/os_unix.c \
  $(TOP)/src/os_win.c \
  $(TOP)/src/pager.c \
  $(TOP)/src/pragma.c \
  $(TOP)/src/prepare.c \
  $(TOP)/src/printf.c \
  $(TOP)/src/random.c \

mutex.lo:	$(TOP)/src/mutex.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mutex.c

mutex_noop.lo:	$(TOP)/src/mutex_noop.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mutex_noop.c

mutex_os2.lo:	$(TOP)/src/mutex_os2.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mutex_os2.c

mutex_unix.lo:	$(TOP)/src/mutex_unix.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mutex_unix.c

mutex_w32.lo:	$(TOP)/src/mutex_w32.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mutex_w32.c

notify.lo:	$(TOP)/src/notify.c $(HDR)

os_unix.lo:	$(TOP)/src/os_unix.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/os_unix.c

os_win.lo:	$(TOP)/src/os_win.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/os_win.c

os_os2.lo:	$(TOP)/src/os_os2.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/os_os2.c

pragma.lo:	$(TOP)/src/pragma.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/pragma.c

prepare.lo:	$(TOP)/src/prepare.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/prepare.c

printf.lo:	$(TOP)/src/printf.c $(HDR)

fts3_tokenizer.lo:	$(TOP)/ext/fts3/fts3_tokenizer.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_tokenizer.c

fts3_tokenizer1.lo:	$(TOP)/ext/fts3/fts3_tokenizer1.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_tokenizer1.c







fts3_write.lo:	$(TOP)/ext/fts3/fts3_write.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_write.c

rtree.lo:	$(TOP)/ext/rtree/rtree.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/rtree/rtree.c

	rm -rf quota2a quota2b quota2c
	rm -rf tsrc .target_source
	rm -f tclsqlite3$(TEXE)
	rm -f testfixture$(TEXE) test.db
	rm -f sqlite3.dll sqlite3.lib sqlite3.exp sqlite3.def
	rm -f sqlite3.c
	rm -f sqlite3_analyzer$(TEXE) sqlite3_analyzer.c


distclean:	clean
	rm -f config.log config.status libtool Makefile sqlite3.pc

#
# Windows section
#

# Set this non-0 to create and use the SQLite amalgamation file.
#
USE_AMALGAMATION = 1

# Set this non-0 to use the International Components for Unicode (ICU).
#
USE_ICU = 0










# Set this non-0 to compile binaries suitable for the WinRT environment.
# This setting does not apply to any binaries that require Tcl to operate
# properly (i.e. the text fixture, etc).
#
FOR_WINRT = 0






# Set this to non-0 to create and use PDBs.
#
SYMBOLS = 1









# Set this to one of the following values to enable various debugging
# features.  Each level includes the debugging options from the previous
# levels.  Currently, the recognized values for DEBUG are:
#
# 0 == NDEBUG: Disables assert() and other runtime diagnostics.
# 1 == Disables NDEBUG and all optimizations and then enables PDBs.
# 2 == SQLITE_DEBUG: Enables various diagnostics messages and code.
# 3 == SQLITE_WIN32_MALLOC_VALIDATE: Validate the Win32 native heap per call.
# 4 == SQLITE_DEBUG_OS_TRACE: Enables output from the OSTRACE() macros.
# 5 == SQLITE_ENABLE_IOTRACE: Enables output from the IOTRACE() macros.
#
DEBUG = 0

























































# C Compiler and options for use in building executables that
# will run on the platform that is doing the build.
#
BCC = cl.exe -W3









# C Compile and options for use in building executables that
# will run on the target platform.  (BCC and TCC are usually the
# same unless your are cross-compiling.)
#
TCC = cl.exe -W3 -DSQLITE_OS_WIN=1 -I. -I$(TOP)\src -fp:precise

# When compiling the library for use in the WinRT environment,
# the following compile-time options must be used as well to
# disable use of Win32 APIs that are not available and to enable
# use of Win32 APIs that are specific to Windows 8 and/or WinRT.






# Also, we need to dynamically link to the MSVC runtime when
# compiling for WinRT.


#
!IF $(FOR_WINRT)!=0

TCC = $(TCC) -DSQLITE_OS_WINRT=1 -MD









!ENDIF

# The mksqlite3c.tcl and mksqlite3h.tcl scripts will pull in
# any extension header files by default.  For non-amalgamation
# builds, we need to make sure the compiler can find these.
#
!IF $(USE_AMALGAMATION)==0

!ENDIF

!IF $(DEBUG)>4
TCC = $(TCC) -DSQLITE_ENABLE_IOTRACE
!ENDIF

#
# Prevent warnings about "insecure" runtime library functions being used.

#
TCC = $(TCC) -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS
BCC = $(BCC) -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS

#












# Use native Win32 heap instead of malloc/free?
#

# TCC = $(TCC) -DSQLITE_WIN32_MALLOC=1

#
# Validate the heap on every call into the native Win32 heap subsystem?
#
!IF $(DEBUG)>2
TCC = $(TCC) -DSQLITE_WIN32_MALLOC_VALIDATE=1

!ENDIF

# The locations of the Tcl header and library files.  Also, the library that
# non-stubs enabled programs using Tcl must link against.  These variables
# (TCLINCDIR, TCLLIBDIR, and LIBTCL) may be overridden via the environment
# prior to running nmake in order to match the actual installed location and
# version on this machine.
#
!if "$(TCLINCDIR)" == ""
TCLINCDIR = c:\tcl\include
!endif

!if "$(TCLLIBDIR)" == ""
TCLLIBDIR = c:\tcl\lib
!endif

!if "$(LIBTCL)" == ""
LIBTCL = tcl85.lib
!endif

# The locations of the ICU header and library files.  These variables
# (ICUINCDIR, ICULIBDIR, and LIBICU) may be overridden via the environment
# prior to running nmake in order to match the actual installed location on
# this machine.
#
!if "$(ICUINCDIR)" == ""
ICUINCDIR = c:\icu\include
!endif

!if "$(ICULIBDIR)" == ""
ICULIBDIR = c:\icu\lib
!endif

!if "$(LIBICU)" == ""
LIBICU = icuuc.lib icuin.lib
!endif

# This is the command to use for tclsh - normally just "tclsh", but we may
# know the specific version we want to use.  This variable (TCLSH_CMD) may be
# overridden via the environment prior to running nmake in order to select a
# specific Tcl shell to use.
#
!if "$(TCLSH_CMD)" == ""
TCLSH_CMD = tclsh85
!endif

# Compiler options needed for programs that use the readline() library.
#
READLINE_FLAGS = -DHAVE_READLINE=0

# The library that programs using readline() must link against.
#
LIBREADLINE =

# Should the database engine be compiled threadsafe
#
TCC = $(TCC) -DSQLITE_THREADSAFE=1

# Do threads override each others locks by default (1), or do we test (-1)
#
TCC = $(TCC) -DSQLITE_THREAD_OVERRIDE_LOCK=-1

# Any target libraries which libsqlite must be linked against
#
!if "$(TLIBS)" == ""
TLIBS =
!endif

# Flags controlling use of the in memory btree implementation
#
# SQLITE_TEMP_STORE is 0 to force temporary tables to be in a file, 1 to
# default to file, 2 to default to memory, and 3 to force temporary
# tables to always be in memory.
#

LTLIB = lib.exe
LTLINK = $(TCC) -Fe$@

# If a platform was set, force the linker to target that.
# Note that the vcvars*.bat family of batch files typically
# set this for you.  Otherwise, the linker will attempt
# to deduce the binary type based on the object files.
!IF "$(PLATFORM)"!=""
LTLINKOPTS = /MACHINE:$(PLATFORM)
LTLIBOPTS = /MACHINE:$(PLATFORM)
!ENDIF

# When compiling for use in the WinRT environment, the following
# linker option must be used to mark the executable as runnable
# only in the context of an application container.
#
!IF $(FOR_WINRT)!=0
LTLINKOPTS = $(LTLINKOPTS) /APPCONTAINER
!ENDIF

# If either debugging or symbols are enabled, enable PDBs.
!IF $(DEBUG)>0 || $(SYMBOLS)!=0
LTLINKOPTS = $(LTLINKOPTS) /DEBUG
BCC = $(BCC) /DEBUG
!ENDIF

# Start with the Tcl related linker options.

LTLIBPATHS = /LIBPATH:$(TCLLIBDIR)
LTLIBS = $(LIBTCL)


# If ICU support is enabled, add the linker options for it.
!IF $(USE_ICU)!=0
LTLIBPATHS = $(LTLIBPATHS) /LIBPATH:$(ICULIBDIR)
LTLIBS = $(LTLIBS) $(LIBICU)
!ENDIF

         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo journal.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.lo \
         memjournal.lo \
         mutex.lo mutex_noop.lo mutex_os2.lo mutex_unix.lo mutex_w32.lo \
         notify.lo opcodes.lo os.lo os_os2.lo os_unix.lo os_win.lo \
         pager.lo parse.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo select.lo status.lo \
         table.lo tokenize.lo trigger.lo \
         update.lo util.lo vacuum.lo \
         vdbe.lo vdbeapi.lo vdbeaux.lo vdbeblob.lo vdbemem.lo vdbesort.lo \
         vdbetrace.lo wal.lo walker.lo where.lo utf.lo vtab.lo

  $(TOP)\src\mem2.c \
  $(TOP)\src\mem3.c \
  $(TOP)\src\mem5.c \
  $(TOP)\src\memjournal.c \
  $(TOP)\src\mutex.c \
  $(TOP)\src\mutex.h \
  $(TOP)\src\mutex_noop.c \
  $(TOP)\src\mutex_os2.c \
  $(TOP)\src\mutex_unix.c \
  $(TOP)\src\mutex_w32.c \
  $(TOP)\src\notify.c \
  $(TOP)\src\os.c \
  $(TOP)\src\os.h \
  $(TOP)\src\os_common.h \
  $(TOP)\src\os_os2.c \
  $(TOP)\src\os_unix.c \
  $(TOP)\src\os_win.c \
  $(TOP)\src\pager.c \
  $(TOP)\src\pager.h \
  $(TOP)\src\parse.y \
  $(TOP)\src\pcache.c \
  $(TOP)\src\pcache.h \

  $(TOP)\src\date.c \
  $(TOP)\src\expr.c \
  $(TOP)\src\func.c \
  $(TOP)\src\insert.c \
  $(TOP)\src\wal.c \
  $(TOP)\src\mem5.c \
  $(TOP)\src\os.c \
  $(TOP)\src\os_os2.c \
  $(TOP)\src\os_unix.c \
  $(TOP)\src\os_win.c \
  $(TOP)\src\pager.c \
  $(TOP)\src\pragma.c \
  $(TOP)\src\prepare.c \
  $(TOP)\src\printf.c \
  $(TOP)\src\random.c \

# Rules to build the LEMON compiler generator
#
lempar.c:	$(TOP)\src\lempar.c
	copy $(TOP)\src\lempar.c .

lemon.exe:	$(TOP)\tool\lemon.c lempar.c
	$(BCC) -Fe$@ $(TOP)\tool\lemon.c

# Rules to build individual *.lo files from generated *.c files. This
# applies to:
#
#     parse.lo
#     opcodes.lo
#

mutex.lo:	$(TOP)\src\mutex.c $(HDR)
	$(LTCOMPILE) -c $(TOP)\src\mutex.c

mutex_noop.lo:	$(TOP)\src\mutex_noop.c $(HDR)
	$(LTCOMPILE) -c $(TOP)\src\mutex_noop.c

mutex_os2.lo:	$(TOP)\src\mutex_os2.c $(HDR)
	$(LTCOMPILE) -c $(TOP)\src\mutex_os2.c

mutex_unix.lo:	$(TOP)\src\mutex_unix.c $(HDR)
	$(LTCOMPILE) -c $(TOP)\src\mutex_unix.c

mutex_w32.lo:	$(TOP)\src\mutex_w32.c $(HDR)
	$(LTCOMPILE) -c $(TOP)\src\mutex_w32.c

notify.lo:	$(TOP)\src\notify.c $(HDR)

os_unix.lo:	$(TOP)\src\os_unix.c $(HDR)
	$(LTCOMPILE) -c $(TOP)\src\os_unix.c

os_win.lo:	$(TOP)\src\os_win.c $(HDR)
	$(LTCOMPILE) -c $(TOP)\src\os_win.c

os_os2.lo:	$(TOP)\src\os_os2.c $(HDR)
	$(LTCOMPILE) -c $(TOP)\src\os_os2.c

pragma.lo:	$(TOP)\src\pragma.c $(HDR)
	$(LTCOMPILE) -c $(TOP)\src\pragma.c

prepare.lo:	$(TOP)\src\prepare.c $(HDR)
	$(LTCOMPILE) -c $(TOP)\src\prepare.c

printf.lo:	$(TOP)\src\printf.c $(HDR)

	move parse.h parse.h.temp
	$(NAWK) -f $(TOP)\addopcodes.awk parse.h.temp > parse.h

sqlite3.h:	$(TOP)\src\sqlite.h.in $(TOP)\manifest.uuid $(TOP)\VERSION
	$(TCLSH_CMD) $(TOP)\tool\mksqlite3h.tcl $(TOP) > sqlite3.h

mkkeywordhash.exe:	$(TOP)\tool\mkkeywordhash.c
	$(BCC) -Femkkeywordhash.exe $(OPT_FEATURE_FLAGS) $(OPTS) $(TOP)\tool\mkkeywordhash.c

keywordhash.h:	$(TOP)\tool\mkkeywordhash.c mkkeywordhash.exe
	.\mkkeywordhash.exe > keywordhash.h



# Rules to build the extension objects.

	-rmdir /Q/S tsrc
	del /Q .target_source
	del /Q tclsqlite3.exe
	del /Q testfixture.exe testfixture.exp test.db
	del /Q sqlite3.dll sqlite3.lib sqlite3.exp sqlite3.def
	del /Q sqlite3.c
	del /Q sqlite3_analyzer.exe sqlite3_analyzer.exp sqlite3_analyzer.c


#
# Windows section
#
dll: sqlite3.dll

sqlite3.def: libsqlite3.lib
	echo EXPORTS > sqlite3.def
	dumpbin /all libsqlite3.lib \
		| $(NAWK) "/ 1 _?sqlite3_/ { sub(/^.* _?/,\"\");print }" \
		| sort >> sqlite3.def

sqlite3.dll: $(LIBOBJ) sqlite3.def
	link $(LTLINKOPTS) $(LTLIBPATHS) /DLL /DEF:sqlite3.def /OUT:$@ $(LIBOBJ) $(LTLIBS) $(TLIBS)

         callback.o complete.o date.o delete.o expr.o fault.o \
         fts3.o fts3_expr.o fts3_hash.o fts3_icu.o fts3_porter.o \
         fts3_tokenizer.o fts3_tokenizer1.o \
         func.o global.o hash.o \
         icu.o insert.o journal.o legacy.o loadext.o \
         main.o malloc.o mem0.o mem1.o mem2.o mem3.o mem5.o \
         memjournal.o \
         mutex.o mutex_noop.o mutex_os2.o mutex_unix.o mutex_w32.o \
         notify.o opcodes.o os.o os_os2.o os_unix.o os_win.o \
         pager.o parse.o pcache.o pcache1.o pragma.o prepare.o printf.o \
         random.o resolve.o rowset.o rtree.o select.o status.o \
         table.o tokenize.o trigger.o \
         update.o util.o vacuum.o \
         vdbe.o vdbeapi.o vdbeaux.o vdbeblob.o vdbemem.o \
         walker.o where.o utf.o vtab.o

  $(TOP)/src/mem2.c \
  $(TOP)/src/mem3.c \
  $(TOP)/src/mem5.c \
  $(TOP)/src/memjournal.c \
  $(TOP)/src/mutex.c \
  $(TOP)/src/mutex.h \
  $(TOP)/src/mutex_noop.c \
  $(TOP)/src/mutex_os2.c \
  $(TOP)/src/mutex_unix.c \
  $(TOP)/src/mutex_w32.c \
  $(TOP)/src/notify.c \
  $(TOP)/src/os.c \
  $(TOP)/src/os.h \
  $(TOP)/src/os_common.h \
  $(TOP)/src/os_os2.c \
  $(TOP)/src/os_unix.c \
  $(TOP)/src/os_win.c \
  $(TOP)/src/pager.c \
  $(TOP)/src/pager.h \
  $(TOP)/src/parse.y \
  $(TOP)/src/pcache.c \
  $(TOP)/src/pcache.h \

#TESTSRC += $(TOP)/ext/fts2/fts2_tokenizer.c
#TESTSRC += $(TOP)/ext/fts3/fts3_tokenizer.c

TESTSRC2 = \
  $(TOP)/src/attach.c $(TOP)/src/backup.c $(TOP)/src/btree.c                   \
  $(TOP)/src/build.c $(TOP)/src/ctime.c $(TOP)/src/date.c                      \
  $(TOP)/src/expr.c $(TOP)/src/func.c $(TOP)/src/insert.c $(TOP)/src/os.c      \
  $(TOP)/src/os_os2.c $(TOP)/src/os_unix.c $(TOP)/src/os_win.c                 \
  $(TOP)/src/pager.c $(TOP)/src/pragma.c $(TOP)/src/prepare.c                  \
  $(TOP)/src/printf.c $(TOP)/src/random.c $(TOP)/src/pcache.c                  \
  $(TOP)/src/pcache1.c $(TOP)/src/select.c $(TOP)/src/tokenize.c               \
  $(TOP)/src/utf.c $(TOP)/src/util.c $(TOP)/src/vdbeapi.c $(TOP)/src/vdbeaux.c \
  $(TOP)/src/vdbe.c $(TOP)/src/vdbemem.c $(TOP)/src/where.c parse.c            \
  $(TOP)/ext/fts3/fts3.c $(TOP)/ext/fts3/fts3_expr.c                           \
  $(TOP)/ext/fts3/fts3_tokenizer.c                                             \

3.7.13

#! /bin/sh
# Guess values for system-dependent variables and create Makefiles.
# Generated by GNU Autoconf 2.62 for sqlite 3.7.13.
#
# Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
# 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
# This configure script is free software; the Free Software Foundation
# gives unlimited permission to copy, distribute and modify it.
## --------------------- ##
## M4sh Initialization.  ##

MFLAGS=
MAKEFLAGS=
SHELL=${CONFIG_SHELL-/bin/sh}

# Identity of this package.
PACKAGE_NAME='sqlite'
PACKAGE_TARNAME='sqlite'
PACKAGE_VERSION='3.7.13'
PACKAGE_STRING='sqlite 3.7.13'
PACKAGE_BUGREPORT=''

# Factoring default headers for most tests.
ac_includes_default="\
#include <stdio.h>
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>

#
# Report the --help message.
#
if test "$ac_init_help" = "long"; then
  # Omit some internal or obsolete options to make the list less imposing.
  # This message is too long to be a string in the A/UX 3.1 sh.
  cat <<_ACEOF
\`configure' configures sqlite 3.7.13 to adapt to many kinds of systems.

Usage: $0 [OPTION]... [VAR=VALUE]...

To assign environment variables (e.g., CC, CFLAGS...), specify them as
VAR=VALUE.  See below for descriptions of some of the useful variables.

Defaults for the options are specified in brackets.

  --build=BUILD     configure for building on BUILD [guessed]
  --host=HOST       cross-compile to build programs to run on HOST [BUILD]
_ACEOF
fi

if test -n "$ac_init_help"; then
  case $ac_init_help in
     short | recursive ) echo "Configuration of sqlite 3.7.13:";;
   esac
  cat <<\_ACEOF

Optional Features:
  --disable-option-checking  ignore unrecognized --enable/--with options
  --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
  --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]

    cd "$ac_pwd" || { ac_status=$?; break; }
  done
fi

test -n "$ac_init_help" && exit $ac_status
if $ac_init_version; then
  cat <<\_ACEOF
sqlite configure 3.7.13
generated by GNU Autoconf 2.62

Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
This configure script is free software; the Free Software Foundation
gives unlimited permission to copy, distribute and modify it.
_ACEOF
  exit
fi
cat >config.log <<_ACEOF
This file contains any messages produced by compilers while
running configure, to aid debugging if configure makes a mistake.

It was created by sqlite $as_me 3.7.13, which was
generated by GNU Autoconf 2.62.  Invocation command line was

  $ $0 $@

_ACEOF
exec 5>>config.log
{

        { { $as_echo "$as_me:$LINENO: error: ${with_tclconfig} directory doesn't contain tclConfig.sh" >&5
$as_echo "$as_me: error: ${with_tclconfig} directory doesn't contain tclConfig.sh" >&2;}
   { (exit 1); exit 1; }; }
      fi
    fi

    # Start autosearch by asking tclsh

    if test x"$cross_compiling" = xno; then
      for i in `echo 'puts stdout $auto_path' | ${TCLSH_CMD}`
      do
        if test -f "$i/tclConfig.sh" ; then
          ac_cv_c_tclconfig="$i"
          break
        fi
      done

    fi

    # then check for a private Tcl installation
    if test x"${ac_cv_c_tclconfig}" = x ; then
      for i in \
            ../tcl \
            `ls -dr ../tcl[8-9].[0-9].[0-9]* 2>/dev/null` \

exec 6>&1

# Save the log message, to keep $[0] and so on meaningful, and to
# report actual input values of CONFIG_FILES etc. instead of their
# values after options handling.
ac_log="
This file was extended by sqlite $as_me 3.7.13, which was
generated by GNU Autoconf 2.62.  Invocation command line was

  CONFIG_FILES    = $CONFIG_FILES
  CONFIG_HEADERS  = $CONFIG_HEADERS
  CONFIG_LINKS    = $CONFIG_LINKS
  CONFIG_COMMANDS = $CONFIG_COMMANDS
  $ $0 $@

$config_commands

Report bugs to <bug-autoconf@gnu.org>."

_ACEOF
cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
ac_cs_version="\\
sqlite config.status 3.7.13
configured by $0, generated by GNU Autoconf 2.62,
  with options \\"`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`\\"

Copyright (C) 2008 Free Software Foundation, Inc.
This config.status script is free software; the Free Software Foundation
gives unlimited permission to copy, distribute and modify it."

        ac_cv_c_tclconfig=`(cd ${with_tclconfig}; pwd)`
      else
        AC_MSG_ERROR([${with_tclconfig} directory doesn't contain tclConfig.sh])
      fi
    fi

    # Start autosearch by asking tclsh

    if test x"$cross_compiling" = xno; then
      for i in `echo 'puts stdout $auto_path' | ${TCLSH_CMD}`
      do
        if test -f "$i/tclConfig.sh" ; then
          ac_cv_c_tclconfig="$i"
          break
        fi
      done

    fi

    # then check for a private Tcl installation
    if test x"${ac_cv_c_tclconfig}" = x ; then
      for i in \
            ../tcl \
            `ls -dr ../tcl[[8-9]].[[0-9]].[[0-9]]* 2>/dev/null` \

  int nToken = 0;
  int nOr = 0;

  /* Allocate a MultiSegReader for each token in the expression. */
  fts3EvalAllocateReaders(pCsr, pCsr->pExpr, &nToken, &nOr, &rc);

  /* Determine which, if any, tokens in the expression should be deferred. */

  if( rc==SQLITE_OK && nToken>1 && pTab->bFts4 ){
    Fts3TokenAndCost *aTC;
    Fts3Expr **apOr;
    aTC = (Fts3TokenAndCost *)sqlite3_malloc(
        sizeof(Fts3TokenAndCost) * nToken
      + sizeof(Fts3Expr *) * nOr * 2
    );

          rc = fts3EvalSelectDeferred(pCsr, apOr[ii], aTC, nToken);
        }
      }

      sqlite3_free(aTC);
    }
  }


  fts3EvalStartReaders(pCsr, pCsr->pExpr, 1, &rc);
  return rc;
}

/*
** Invalidate the current position list for phrase pPhrase.

        bHit = (
            fts3EvalTestExpr(pCsr, pExpr->pLeft, pRc)
         && !fts3EvalTestExpr(pCsr, pExpr->pRight, pRc)
        );
        break;

      default: {

        if( pCsr->pDeferred 
         && (pExpr->iDocid==pCsr->iPrevId || pExpr->bDeferred)
        ){
          Fts3Phrase *pPhrase = pExpr->pPhrase;
          assert( pExpr->bDeferred || pPhrase->doclist.bFreeList==0 );
          if( pExpr->bDeferred ){
            fts3EvalInvalidatePoslist(pPhrase);
          }
          *pRc = fts3EvalDeferredPhrase(pCsr, pPhrase);
          bHit = (pPhrase->doclist.pList!=0);
          pExpr->iDocid = pCsr->iPrevId;
        }else{


          bHit = (pExpr->bEof==0 && pExpr->iDocid==pCsr->iPrevId);
        }
        break;
      }
    }
  }
  return bHit;

int sqlite3Fts3AllSegdirs(Fts3Table*, int, int, int, sqlite3_stmt **);
int sqlite3Fts3ReadLock(Fts3Table *);
int sqlite3Fts3ReadBlock(Fts3Table*, sqlite3_int64, char **, int*, int*);

int sqlite3Fts3SelectDoctotal(Fts3Table *, sqlite3_stmt **);
int sqlite3Fts3SelectDocsize(Fts3Table *, sqlite3_int64, sqlite3_stmt **);


void sqlite3Fts3FreeDeferredTokens(Fts3Cursor *);
int sqlite3Fts3DeferToken(Fts3Cursor *, Fts3PhraseToken *, int);
int sqlite3Fts3CacheDeferredDoclists(Fts3Cursor *);
void sqlite3Fts3FreeDeferredDoclists(Fts3Cursor *);









void sqlite3Fts3SegmentsClose(Fts3Table *);
int sqlite3Fts3MaxLevel(Fts3Table *, int *);

/* Special values interpreted by sqlite3SegReaderCursor() */
#define FTS3_SEGCURSOR_PENDING        -1
#define FTS3_SEGCURSOR_ALL            -2

    Fts3Table*, Fts3MultiSegReader*, int, const char*, int);
int sqlite3Fts3MsrIncrNext(
    Fts3Table *, Fts3MultiSegReader *, sqlite3_int64 *, char **, int *);
int sqlite3Fts3EvalPhrasePoslist(Fts3Cursor *, Fts3Expr *, int iCol, char **); 
int sqlite3Fts3MsrOvfl(Fts3Cursor *, Fts3MultiSegReader *, int *);
int sqlite3Fts3MsrIncrRestart(Fts3MultiSegReader *pCsr);

int sqlite3Fts3DeferredTokenList(Fts3DeferredToken *, char **, int *);

/* fts3_unicode2.c (functions generated by parsing unicode text files) */
#ifdef SQLITE_ENABLE_FTS4_UNICODE61
int sqlite3FtsUnicodeFold(int, int);
int sqlite3FtsUnicodeIsalnum(int);
int sqlite3FtsUnicodeIsdiacritic(int);
#endif

#endif /* !SQLITE_CORE || SQLITE_ENABLE_FTS3 */
#endif /* _FTSINT_H */

    iEnd = ubrk_next(pCsr->pIter);
    if( iEnd==UBRK_DONE ){
      return SQLITE_DONE;
    }

    while( iStart<iEnd ){
      int iWhite = iStart;
      U8_NEXT(pCsr->aChar, iWhite, pCsr->nChar, c);
      if( u_isspace(c) ){
        iStart = iWhite;
      }else{
        break;
      }
    }
    assert(iStart<=iEnd);

        iLo = iTest+1;
      }else{
        iHi = iTest-1;
      }
    }
    assert( aEntry[0]<key );
    assert( key>=aEntry[iRes] );
    return (c >= ((aEntry[iRes]>>10) + (aEntry[iRes]&0x3FF)));
  }
  return 1;
}


/*
** If the argument is a codepoint corresponding to a lowercase letter

  }else{
    rc = SQLITE_ERROR;
  }

  return rc;
}


/*
** Delete all cached deferred doclists. Deferred doclists are cached
** (allocated) by the sqlite3Fts3CacheDeferredDoclists() function.
*/
void sqlite3Fts3FreeDeferredDoclists(Fts3Cursor *pCsr){
  Fts3DeferredToken *pDef;
  for(pDef=pCsr->pDeferred; pDef; pDef=pDef->pNext){

  pCsr->pDeferred = pDeferred;

  assert( pToken->pDeferred==0 );
  pToken->pDeferred = pDeferred;

  return SQLITE_OK;
}


/*
** SQLite value pRowid contains the rowid of a row that may or may not be
** present in the FTS3 table. If it is, delete it and adjust the contents
** of subsiduary data structures accordingly.
*/
static int fts3DeleteByRowid(

         fts3.o fts3_aux.o fts3_expr.o fts3_hash.o fts3_icu.o fts3_porter.o \
         fts3_snippet.o fts3_tokenizer.o fts3_tokenizer1.o \
	 fts3_unicode.o fts3_unicode2.o \
         fts3_write.o func.o global.o hash.o \
         icu.o insert.o journal.o legacy.o loadext.o \
         main.o malloc.o mem0.o mem1.o mem2.o mem3.o mem5.o \
         memjournal.o \
         mutex.o mutex_noop.o mutex_os2.o mutex_unix.o mutex_w32.o \
         notify.o opcodes.o os.o os_os2.o os_unix.o os_win.o \
         pager.o parse.o pcache.o pcache1.o pragma.o prepare.o printf.o \
         random.o resolve.o rowset.o rtree.o select.o status.o \
         table.o tokenize.o trigger.o \
         update.o util.o vacuum.o \
         vdbe.o vdbeapi.o vdbeaux.o vdbeblob.o vdbemem.o vdbesort.o \
	 vdbetrace.o wal.o walker.o where.o utf.o vtab.o

  $(TOP)/src/mem2.c \
  $(TOP)/src/mem3.c \
  $(TOP)/src/mem5.c \
  $(TOP)/src/memjournal.c \
  $(TOP)/src/mutex.c \
  $(TOP)/src/mutex.h \
  $(TOP)/src/mutex_noop.c \
  $(TOP)/src/mutex_os2.c \
  $(TOP)/src/mutex_unix.c \
  $(TOP)/src/mutex_w32.c \
  $(TOP)/src/notify.c \
  $(TOP)/src/os.c \
  $(TOP)/src/os.h \
  $(TOP)/src/os_common.h \
  $(TOP)/src/os_os2.c \
  $(TOP)/src/os_unix.c \
  $(TOP)/src/os_win.c \
  $(TOP)/src/pager.c \
  $(TOP)/src/pager.h \
  $(TOP)/src/parse.y \
  $(TOP)/src/pcache.c \
  $(TOP)/src/pcache.h \

  $(TOP)/src/date.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/insert.c \
  $(TOP)/src/wal.c \
  $(TOP)/src/mem5.c \
  $(TOP)/src/os.c \
  $(TOP)/src/os_os2.c \
  $(TOP)/src/os_unix.c \
  $(TOP)/src/os_win.c \
  $(TOP)/src/pager.c \
  $(TOP)/src/pragma.c \
  $(TOP)/src/prepare.c \
  $(TOP)/src/printf.c \
  $(TOP)/src/random.c \

	rm -f testloadext.dll libtestloadext.so
	rm -f amalgamation-testfixture amalgamation-testfixture.exe
	rm -f fts3-testfixture fts3-testfixture.exe
	rm -f testfixture testfixture.exe
	rm -f threadtest3 threadtest3.exe
	rm -f sqlite3.c fts?amal.c tclsqlite3.c
	rm -f sqlite3_analyzer sqlite3_analyzer.exe sqlite3_analyzer.c

      ** side-effect of the CREATE TABLE statement is to leave the rootpage 
      ** of the new table in register pParse->regRoot. This is important 
      ** because the OpenWrite opcode below will be needing it. */
      sqlite3NestedParse(pParse,
          "CREATE TABLE %Q.%s(%s)", pDb->zName, zTab, aTable[i].zCols
      );
      aRoot[i] = pParse->regRoot;
      aCreateTbl[i] = 1;
    }else{
      /* The table already exists. If zWhere is not NULL, delete all entries 
      ** associated with the table zWhere. If zWhere is NULL, delete the
      ** entire contents of the table. */
      aRoot[i] = pStat->tnum;
      sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
      if( zWhere ){

  int mxSample;
  int n;

  UNUSED_PARAMETER(argc);
  nRow = (tRowcnt)sqlite3_value_int64(argv[0]);
  mxSample = sqlite3_value_int(argv[1]);
  n = sizeof(*p) + sizeof(p->a[0])*mxSample;
  p = sqlite3_malloc( n );
  if( p==0 ){
    sqlite3_result_error_nomem(context);
    return;
  }
  memset(p, 0, n);
  p->a = (struct Stat3Sample*)&p[1];
  p->nRow = nRow;
  p->mxSample = mxSample;
  p->nPSample = p->nRow/(mxSample/3+1) + 1;
  sqlite3_randomness(sizeof(p->iPrn), &p->iPrn);
  sqlite3_result_blob(context, p, sizeof(p), sqlite3_free);
}

    );
    p = 0;
  }else {
    /* Allocate space for a new sqlite3_backup object...
    ** EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
    ** call to sqlite3_backup_init() and is destroyed by a call to
    ** sqlite3_backup_finish(). */
    p = (sqlite3_backup *)sqlite3_malloc(sizeof(sqlite3_backup));
    if( !p ){
      sqlite3Error(pDestDb, SQLITE_NOMEM, 0);
    }
  }

  /* If the allocation succeeded, populate the new object. */
  if( p ){
    memset(p, 0, sizeof(sqlite3_backup));
    p->pSrc = findBtree(pDestDb, pSrcDb, zSrcDb);
    p->pDest = findBtree(pDestDb, pDestDb, zDestDb);
    p->pDestDb = pDestDb;
    p->pSrcDb = pSrcDb;
    p->iNext = 1;
    p->isAttached = 0;

}

/*
** Release all resources associated with an sqlite3_backup* handle.
*/
int sqlite3_backup_finish(sqlite3_backup *p){
  sqlite3_backup **pp;                 /* Ptr to head of pagers backup list */
  MUTEX_LOGIC( sqlite3_mutex *mutex; ) /* Mutex to protect source database */
  int rc;                              /* Value to return */

  /* Enter the mutexes */
  if( p==0 ) return SQLITE_OK;

  sqlite3_mutex_enter(p->pSrcDb->mutex);
  sqlite3BtreeEnter(p->pSrc);
  MUTEX_LOGIC( mutex = p->pSrcDb->mutex; )
  if( p->pDestDb ){
    sqlite3_mutex_enter(p->pDestDb->mutex);
  }

  /* Detach this backup from the source pager. */
  if( p->pDestDb ){
    p->pSrc->nBackup--;

  /* Set the error code of the destination database handle. */
  rc = (p->rc==SQLITE_DONE) ? SQLITE_OK : p->rc;
  sqlite3Error(p->pDestDb, rc, 0);

  /* Exit the mutexes and free the backup context structure. */
  if( p->pDestDb ){
    sqlite3_mutex_leave(p->pDestDb->mutex);
  }
  sqlite3BtreeLeave(p->pSrc);
  if( p->pDestDb ){
    /* EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
    ** call to sqlite3_backup_init() and is destroyed by a call to
    ** sqlite3_backup_finish(). */
    sqlite3_free(p);
  }
  sqlite3_mutex_leave(mutex);
  return rc;
}

/*
** Return the number of pages still to be backed up as of the most recent
** call to sqlite3_backup_step().
*/

  int rc = -1;
  int i, nx, pc, op;
  void *pTmpSpace;

  /* Allocate the Bitvec to be tested and a linear array of
  ** bits to act as the reference */
  pBitvec = sqlite3BitvecCreate( sz );
  pV = sqlite3_malloc( (sz+7)/8 + 1 );
  pTmpSpace = sqlite3_malloc(BITVEC_SZ);
  if( pBitvec==0 || pV==0 || pTmpSpace==0  ) goto bitvec_end;
  memset(pV, 0, (sz+7)/8 + 1);

  /* NULL pBitvec tests */
  sqlite3BitvecSet(0, 1);
  sqlite3BitvecClear(0, 1, pTmpSpace);

  /* Run the program */
  pc = 0;

        /* Start of free block is off the page */
        return SQLITE_CORRUPT_BKPT; 
      }
      next = get2byte(&data[pc]);
      size = get2byte(&data[pc+2]);
      if( (next>0 && next<=pc+size+3) || pc+size>usableSize ){
        /* Free blocks must be in ascending order. And the last byte of
	** the free-block must lie on the database page.  */
        return SQLITE_CORRUPT_BKPT; 
      }
      nFree = nFree + size;
      pc = next;
    }

    /* At this point, nFree contains the sum of the offset to the start

          btreeInvokeBusyHandler(pBt) );

  if( rc==SQLITE_OK ){
    if( p->inTrans==TRANS_NONE ){
      pBt->nTransaction++;
#ifndef SQLITE_OMIT_SHARED_CACHE
      if( p->sharable ){
	assert( p->lock.pBtree==p && p->lock.iTable==1 );
        p->lock.eLock = READ_LOCK;
        p->lock.pNext = pBt->pLock;
        pBt->pLock = &p->lock;
      }
#endif
    }
    p->inTrans = (wrflag?TRANS_WRITE:TRANS_READ);

** If aOvflSpace is set to a null pointer, this function returns 
** SQLITE_NOMEM.
*/
static int balance_nonroot(
  MemPage *pParent,               /* Parent page of siblings being balanced */
  int iParentIdx,                 /* Index of "the page" in pParent */
  u8 *aOvflSpace,                 /* page-size bytes of space for parent ovfl */
  int isRoot                      /* True if pParent is a root-page */

){
  BtShared *pBt;               /* The whole database */
  int nCell = 0;               /* Number of cells in apCell[] */
  int nMaxCells = 0;           /* Allocated size of apCell, szCell, aFrom. */
  int nNew = 0;                /* Number of pages in apNew[] */
  int nOld;                    /* Number of pages in apOld[] */
  int i, j, k;                 /* Loop counters */

  ** way, the remainder of the function does not have to deal with any
  ** overflow cells in the parent page, since if any existed they will
  ** have already been removed.
  */
  i = pParent->nOverflow + pParent->nCell;
  if( i<2 ){
    nxDiv = 0;
    nOld = i+1;
  }else{
    nOld = 3;

    if( iParentIdx==0 ){                 
      nxDiv = 0;
    }else if( iParentIdx==i ){
      nxDiv = i-2;
    }else{

      nxDiv = iParentIdx-1;
    }
    i = 2;
  }

  if( (i+nxDiv-pParent->nOverflow)==pParent->nCell ){
    pRight = &pParent->aData[pParent->hdrOffset+8];
  }else{
    pRight = findCell(pParent, i+nxDiv-pParent->nOverflow);
  }
  pgno = get4byte(pRight);
  while( 1 ){

    int r;              /* Index of right-most cell in left sibling */
    int d;              /* Index of first cell to the left of right sibling */

    r = cntNew[i-1] - 1;
    d = r + 1 - leafData;
    assert( d<nMaxCells );
    assert( r<nMaxCells );

    while( szRight==0 || szRight+szCell[d]+2<=szLeft-(szCell[r]+2) ){

      szRight += szCell[d] + 2;
      szLeft -= szCell[r] + 2;
      cntNew[i-1]--;
      r = cntNew[i-1] - 1;
      d = r + 1 - leafData;
    }
    szNew[i] = szRight;

      pNew = apNew[i] = apOld[i];
      apOld[i] = 0;
      rc = sqlite3PagerWrite(pNew->pDbPage);
      nNew++;
      if( rc ) goto balance_cleanup;
    }else{
      assert( i>0 );
      rc = allocateBtreePage(pBt, &pNew, &pgno, pgno, 0);
      if( rc ) goto balance_cleanup;
      apNew[i] = pNew;
      nNew++;

      /* Set the pointer-map entry for the new sibling page. */
      if( ISAUTOVACUUM ){
        ptrmapPut(pBt, pNew->pgno, PTRMAP_BTREE, pParent->pgno, &rc);

    for(i=0; i<nCell; i++){
      int isDivider = 0;
      while( i==iNextOld ){
        /* Cell i is the cell immediately following the last cell on old
        ** sibling page j. If the siblings are not leaf pages of an
        ** intkey b-tree, then cell i was a divider cell. */
        assert( j+1 < ArraySize(apCopy) );

        pOld = apCopy[++j];
        iNextOld = i + !leafData + pOld->nCell + pOld->nOverflow;
        if( pOld->nOverflow ){
          nOverflow = pOld->nOverflow;
          iOverflow = i + !leafData + pOld->aiOvfl[0];
        }
        isDivider = !leafData;  

          ** different page). Once this subsequent call to balance_nonroot() 
          ** has completed, it is safe to release the pSpace buffer used by
          ** the previous call, as the overflow cell data will have been 
          ** copied either into the body of a database page or into the new
          ** pSpace buffer passed to the latter call to balance_nonroot().
          */
          u8 *pSpace = sqlite3PageMalloc(pCur->pBt->pageSize);
          rc = balance_nonroot(pParent, iIdx, pSpace, iPage==1);
          if( pFree ){
            /* If pFree is not NULL, it points to the pSpace buffer used 
            ** by a previous call to balance_nonroot(). Its contents are
            ** now stored either on real database pages or within the 
            ** new pSpace buffer, so it may be safely freed here. */
            sqlite3PageFree(pFree);
          }

      }
    }
  }

  pBt->btsFlags &= ~BTS_NO_WAL;
  return rc;
}

#define BTREE_FILE_FORMAT         2
#define BTREE_DEFAULT_CACHE_SIZE  3
#define BTREE_LARGEST_ROOT_PAGE   4
#define BTREE_TEXT_ENCODING       5
#define BTREE_USER_VERSION        6
#define BTREE_INCR_VACUUM         7







int sqlite3BtreeCursor(
  Btree*,                              /* BTree containing table to open */
  int iTable,                          /* Index of root page */
  int wrFlag,                          /* 1 for writing.  0 for read-only */
  struct KeyInfo*,                     /* First argument to compare function */
  BtCursor *pCursor                    /* Space to write cursor structure */
);

char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
struct Pager *sqlite3BtreePager(Btree*);

int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
void sqlite3BtreeCacheOverflow(BtCursor *);
void sqlite3BtreeClearCursor(BtCursor *);

int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);


#ifndef NDEBUG
int sqlite3BtreeCursorIsValid(BtCursor*);
#endif

#ifndef SQLITE_OMIT_BTREECOUNT
int sqlite3BtreeCount(BtCursor *, i64 *);

  u8 wrFlag;                /* True if writable */
  u8 atLast;                /* Cursor pointing to the last entry */
  u8 validNKey;             /* True if info.nKey is valid */
  u8 eState;                /* One of the CURSOR_XXX constants (see below) */
#ifndef SQLITE_OMIT_INCRBLOB
  u8 isIncrblobHandle;      /* True if this cursor is an incr. io handle */
#endif

  i16 iPage;                            /* Index of current page in apPage */
  u16 aiIdx[BTCURSOR_MAX_DEPTH];        /* Current index in apPage[i] */
  MemPage *apPage[BTCURSOR_MAX_DEPTH];  /* Pages from root to current page */
};

/*
** Potential values for BtCursor.eState.

  /* Delete all indices associated with this table. */
  for(pIndex = pTable->pIndex; pIndex; pIndex=pNext){
    pNext = pIndex->pNext;
    assert( pIndex->pSchema==pTable->pSchema );
    if( !db || db->pnBytesFreed==0 ){
      char *zName = pIndex->zName; 
      TESTONLY ( Index *pOld = ) sqlite3HashInsert(
	  &pIndex->pSchema->idxHash, zName, sqlite3Strlen30(zName), 0
      );
      assert( db==0 || sqlite3SchemaMutexHeld(db, 0, pIndex->pSchema) );
      assert( pOld==pIndex || pOld==0 );
    }
    freeIndex(db, pIndex);
  }

    */
    if( pSelect ){
      SelectDest dest;
      Table *pSelTab;

      assert(pParse->nTab==1);
      sqlite3VdbeAddOp3(v, OP_OpenWrite, 1, pParse->regRoot, iDb);
      sqlite3VdbeChangeP5(v, 1);
      pParse->nTab = 2;
      sqlite3SelectDestInit(&dest, SRT_Table, 1);
      sqlite3Select(pParse, pSelect, &dest);
      sqlite3VdbeAddOp1(v, OP_Close, 1);
      if( pParse->nErr==0 ){
        pSelTab = sqlite3ResultSetOfSelect(pParse, pSelect);
        if( pSelTab==0 ) return;

  }else{
    tnum = pIndex->tnum;
    sqlite3VdbeAddOp2(v, OP_Clear, tnum, iDb);
  }
  pKey = sqlite3IndexKeyinfo(pParse, pIndex);
  sqlite3VdbeAddOp4(v, OP_OpenWrite, iIdx, tnum, iDb, 
                    (char *)pKey, P4_KEYINFO_HANDOFF);
  if( memRootPage>=0 ){
    sqlite3VdbeChangeP5(v, 1);
  }

#ifndef SQLITE_OMIT_MERGE_SORT
  /* Open the sorter cursor if we are to use one. */
  iSorter = pParse->nTab++;
  sqlite3VdbeAddOp4(v, OP_SorterOpen, iSorter, 0, 0, (char*)pKey, P4_KEYINFO);
#else
  iSorter = iTab;

    int iRowid = ++pParse->nMem;    /* Used for storing rowid values. */
    int regRowid;                   /* Actual register containing rowids */

    /* Collect rowids of every row to be deleted.
    */
    sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
    pWInfo = sqlite3WhereBegin(
        pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK
    );
    if( pWInfo==0 ) goto delete_from_cleanup;
    regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid, 0);
    sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, regRowid);
    if( db->flags & SQLITE_CountRows ){
      sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
    }

        ** table allocated and opened above.
        */
        SelectDest dest;
        ExprList *pEList;

        assert( !isRowid );
        sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
        dest.affinity = (u8)affinity;
        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
        pExpr->x.pSelect->iLimit = 0;
        if( sqlite3Select(pParse, pExpr->x.pSelect, &dest) ){
          return 0;
        }
        pEList = pExpr->x.pSelect->pEList;
        if( ALWAYS(pEList!=0 && pEList->nExpr>0) ){ 

      assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT );

      assert( ExprHasProperty(pExpr, EP_xIsSelect) );
      pSel = pExpr->x.pSelect;
      sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
      if( pExpr->op==TK_SELECT ){
        dest.eDest = SRT_Mem;
        sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iParm);
        VdbeComment((v, "Init subquery result"));
      }else{
        dest.eDest = SRT_Exists;
        sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iParm);
        VdbeComment((v, "Init EXISTS result"));
      }
      sqlite3ExprDelete(pParse->db, pSel->pLimit);
      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0,
                                  &sqlite3IntTokens[1]);
      pSel->iLimit = 0;
      if( sqlite3Select(pParse, pSel, &dest) ){
        return 0;
      }
      rReg = dest.iParm;
      ExprSetIrreducible(pExpr);
      break;
    }
  }

  if( testAddr>=0 ){
    sqlite3VdbeJumpHere(v, testAddr);

    case TK_FUNCTION: {
      ExprList *pFarg;       /* List of function arguments */
      if( ExprHasAnyProperty(pExpr, EP_TokenOnly) ){
        pFarg = 0;
      }else{
        pFarg = pExpr->x.pList;
      }

      sqlite3ExplainPrintf(pOut, "%sFUNCTION:%s(",
                           op==TK_AGG_FUNCTION ? "AGG_" : "",


                           pExpr->u.zToken);

      if( pFarg ){
        sqlite3ExplainExprList(pOut, pFarg);
      }
      sqlite3ExplainPrintf(pOut, ")");
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY

    if( pA->a[i].sortOrder!=pB->a[i].sortOrder ) return 1;
    if( sqlite3ExprCompare(pExprA, pExprB) ) return 1;
  }
  return 0;
}

/*



** This is the expression callback for sqlite3FunctionUsesOtherSrc().
**





** Determine if an expression references any table other than one of the
** tables in pWalker->u.pSrcList and abort if it does.


*/
static int exprUsesOtherSrc(Walker *pWalker, Expr *pExpr){





  if( pExpr->op==TK_COLUMN || pExpr->op==TK_AGG_COLUMN ){
    int i;

    SrcList *pSrc = pWalker->u.pSrcList;
    for(i=0; i<pSrc->nSrc; i++){
      if( pExpr->iTable==pSrc->a[i].iCursor ) return WRC_Continue;
    }
    return WRC_Abort;


  }else{
    return WRC_Continue;

  }
}



/*
** Determine if any of the arguments to the pExpr Function references
** any SrcList other than pSrcList.  Return true if they do.  Return
** false if pExpr has no argument or has only constant arguments or
** only references tables named in pSrcList.
*/
static int sqlite3FunctionUsesOtherSrc(Expr *pExpr, SrcList *pSrcList){
  Walker w;

  assert( pExpr->op==TK_AGG_FUNCTION );
  memset(&w, 0, sizeof(w));
  w.xExprCallback = exprUsesOtherSrc;

  w.u.pSrcList = pSrcList;


  if( sqlite3WalkExprList(&w, pExpr->x.pList)!=WRC_Continue ) return 1;
  return 0;
}

/*
** Add a new element to the pAggInfo->aCol[] array.  Return the index of
** the new element.  Return a negative number if malloc fails.
*/
static int addAggInfoColumn(sqlite3 *db, AggInfo *pInfo){

          } /* endif pExpr->iTable==pItem->iCursor */
        } /* end loop over pSrcList */
      }
      return WRC_Prune;
    }
    case TK_AGG_FUNCTION: {
      if( (pNC->ncFlags & NC_InAggFunc)==0
       && !sqlite3FunctionUsesOtherSrc(pExpr, pSrcList)
      ){
        /* Check to see if pExpr is a duplicate of another aggregate 
        ** function that is already in the pAggInfo structure
        */
        struct AggInfo_func *pItem = pAggInfo->aFunc;
        for(i=0; i<pAggInfo->nFunc; i++, pItem++){
          if( sqlite3ExprCompare(pItem->pExpr, pExpr)==0 ){

  sNameContext.pParse = pParse;
  sqlite3ResolveExprNames(&sNameContext, pWhere);

  /* Create VDBE to loop through the entries in pSrc that match the WHERE
  ** clause. If the constraint is not deferred, throw an exception for
  ** each row found. Otherwise, for deferred constraints, increment the
  ** deferred constraint counter by nIncr for each row selected.  */
  pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0, 0, 0);
  if( nIncr>0 && pFKey->isDeferred==0 ){
    sqlite3ParseToplevel(pParse)->mayAbort = 1;
  }
  sqlite3VdbeAddOp2(v, OP_FkCounter, pFKey->isDeferred, nIncr);
  if( pWInfo ){
    sqlite3WhereEnd(pWInfo);
  }

** "NULL".  Otherwise, the argument is enclosed in single quotes with
** single-quote escapes.
*/
static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
  assert( argc==1 );
  UNUSED_PARAMETER(argc);
  switch( sqlite3_value_type(argv[0]) ){
    case SQLITE_INTEGER:











    case SQLITE_FLOAT: {
      sqlite3_result_value(context, argv[0]);
      break;
    }
    case SQLITE_BLOB: {
      char *zText = 0;
      char const *zBlob = sqlite3_value_blob(argv[0]);
      int nBlob = sqlite3_value_bytes(argv[0]);

    new_size = SQLITE_MALLOC_SOFT_LIMIT/sizeof(struct _ht);
  }
  if( new_size==pH->htsize ) return 0;
#endif

  /* The inability to allocates space for a larger hash table is
  ** a performance hit but it is not a fatal error.  So mark the
  ** allocation as a benign.




  */
  sqlite3BeginBenignMalloc();
  new_ht = (struct _ht *)sqlite3Malloc( new_size*sizeof(struct _ht) );
  sqlite3EndBenignMalloc();

  if( new_ht==0 ) return 0;
  sqlite3_free(pH->ht);

    int rc, j1;

    regEof = ++pParse->nMem;
    sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof);      /* EOF <- 0 */
    VdbeComment((v, "SELECT eof flag"));
    sqlite3SelectDestInit(&dest, SRT_Coroutine, ++pParse->nMem);
    addrSelect = sqlite3VdbeCurrentAddr(v)+2;
    sqlite3VdbeAddOp2(v, OP_Integer, addrSelect-1, dest.iParm);
    j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
    VdbeComment((v, "Jump over SELECT coroutine"));

    /* Resolve the expressions in the SELECT statement and execute it. */
    rc = sqlite3Select(pParse, pSelect, &dest);
    assert( pParse->nErr==0 || rc );
    if( rc || NEVER(pParse->nErr) || db->mallocFailed ){
      goto insert_cleanup;
    }
    sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof);         /* EOF <- 1 */
    sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);   /* yield X */
    sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
    VdbeComment((v, "End of SELECT coroutine"));
    sqlite3VdbeJumpHere(v, j1);                          /* label B: */

    regFromSelect = dest.iMem;
    assert( pSelect->pEList );
    nColumn = pSelect->pEList->nExpr;
    assert( dest.nMem==nColumn );

    /* Set useTempTable to TRUE if the result of the SELECT statement
    ** should be written into a temporary table (template 4).  Set to
    ** FALSE if each* row of the SELECT can be written directly into
    ** the destination table (template 3).
    **
    ** A temp table must be used if the table being updated is also one

      int addrTop;         /* Label "L" */
      int addrIf;          /* Address of jump to M */

      srcTab = pParse->nTab++;
      regRec = sqlite3GetTempReg(pParse);
      regTempRowid = sqlite3GetTempReg(pParse);
      sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
      addrTop = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);
      addrIf = sqlite3VdbeAddOp1(v, OP_If, regEof);
      sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec);
      sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regTempRowid);
      sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regTempRowid);
      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrTop);
      sqlite3VdbeJumpHere(v, addrIf);
      sqlite3ReleaseTempReg(pParse, regRec);

    **
    **      C: yield X
    **         if EOF goto D
    **         insert the select result into <table> from R..R+n
    **         goto C
    **      D: ...
    */
    addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);
    addrInsTop = sqlite3VdbeAddOp1(v, OP_If, regEof);
  }

  /* Allocate registers for holding the rowid of the new row,
  ** the content of the new row, and the assemblied row record.
  */
  regRowid = regIns = pParse->nMem+1;

    }
  }
  sqlite3BtreeLeaveAll(db);
#else
  UNUSED_PARAMETER(db);
#endif
}
















/*
** Close an existing SQLite database
*/
int sqlite3_close(sqlite3 *db){
  HashElem *i;                    /* Hash table iterator */
  int j;

  if( !db ){
    return SQLITE_OK;
  }
  if( !sqlite3SafetyCheckSickOrOk(db) ){
    return SQLITE_MISUSE_BKPT;
  }
  sqlite3_mutex_enter(db->mutex);

  /* Force xDisconnect calls on all virtual tables */
  disconnectAllVtab(db);

  /* If a transaction is open, the disconnectAllVtab() call above
  ** will not have called the xDisconnect() method on any virtual
  ** tables in the db->aVTrans[] array. The following sqlite3VtabRollback()
  ** call will do so. We need to do this before the check for active
  ** SQL statements below, as the v-table implementation may be storing
  ** some prepared statements internally.
  */
  sqlite3VtabRollback(db);


  /* If there are any outstanding VMs, return SQLITE_BUSY. */

  if( db->pVdbe ){
    sqlite3Error(db, SQLITE_BUSY, 
        "unable to close due to unfinalised statements");
    sqlite3_mutex_leave(db->mutex);
    return SQLITE_BUSY;
  }
  assert( sqlite3SafetyCheckSickOrOk(db) );






  for(j=0; j<db->nDb; j++){











    Btree *pBt = db->aDb[j].pBt;
    if( pBt && sqlite3BtreeIsInBackup(pBt) ){








      sqlite3Error(db, SQLITE_BUSY, 


          "unable to close due to unfinished backup operation");





      sqlite3_mutex_leave(db->mutex);
      return SQLITE_BUSY;
    }
  }






  /* Free any outstanding Savepoint structures. */
  sqlite3CloseSavepoints(db);

  /* Close all database connections */
  for(j=0; j<db->nDb; j++){
    struct Db *pDb = &db->aDb[j];

    sqlite3_free(db->lookaside.pStart);
  }
#ifdef SQLITE_ENABLE_SQLRR
  SRRecClose(db);
#endif
  
  sqlite3_free(db);
  return SQLITE_OK;
}

/*
** Rollback all database files.  If tripCode is not SQLITE_OK, then
** any open cursors are invalidated ("tripped" - as in "tripping a circuit
** breaker") and made to return tripCode if there are any further
** attempts to use that cursor.

  sysctlbyname("hw.ncpu", &cpuCount, &len, NULL, 0);
  if( cpuCount>1 ){
    /* defer MT decisions to system malloc */
    _sqliteZone_ = malloc_default_zone();
  }else{
    /* only 1 core, use our own zone to contention over global locks, 
    ** e.g. we have our own dedicated locks */
    bool success;		
    malloc_zone_t* newzone = malloc_create_zone(4096, 0);
    malloc_set_zone_name(newzone, "Sqlite_Heap");
    do{
      success = OSAtomicCompareAndSwapPtrBarrier(NULL, newzone, 
                                 (void * volatile *)&_sqliteZone_);
    }while(!_sqliteZone_);
    if( !success ){	
      /* somebody registered a zone first */
      malloc_destroy_zone(newzone);
    }
  }
#endif
  UNUSED_PARAMETER(NotUsed);
  return SQLITE_OK;

**                             mutual exclusion is provided.  But this
**                             implementation can be overridden at
**                             start-time.
**
**   SQLITE_MUTEX_PTHREADS     For multi-threaded applications on Unix.
**
**   SQLITE_MUTEX_W32          For multi-threaded applications on Win32.
**
**   SQLITE_MUTEX_OS2          For multi-threaded applications on OS/2.
*/
#if !SQLITE_THREADSAFE
# define SQLITE_MUTEX_OMIT
#endif
#if SQLITE_THREADSAFE && !defined(SQLITE_MUTEX_NOOP)
#  if SQLITE_OS_UNIX
#    define SQLITE_MUTEX_PTHREADS
#  elif SQLITE_OS_WIN
#    define SQLITE_MUTEX_W32
#  elif SQLITE_OS_OS2
#    define SQLITE_MUTEX_OS2
#  else
#    define SQLITE_MUTEX_NOOP
#  endif
#endif

#ifdef SQLITE_MUTEX_OMIT
/*

/*
** 2007 August 28
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement mutexes for OS/2
*/
#include "sqliteInt.h"

/*
** The code in this file is only used if SQLITE_MUTEX_OS2 is defined.
** See the mutex.h file for details.
*/
#ifdef SQLITE_MUTEX_OS2

/********************** OS/2 Mutex Implementation **********************
**
** This implementation of mutexes is built using the OS/2 API.
*/

/*
** The mutex object
** Each recursive mutex is an instance of the following structure.
*/
struct sqlite3_mutex {
  HMTX mutex;       /* Mutex controlling the lock */
  int  id;          /* Mutex type */
#ifdef SQLITE_DEBUG
 int   trace;       /* True to trace changes */
#endif
};

#ifdef SQLITE_DEBUG
#define SQLITE3_MUTEX_INITIALIZER { 0, 0, 0 }
#else
#define SQLITE3_MUTEX_INITIALIZER { 0, 0 }
#endif

/*
** Initialize and deinitialize the mutex subsystem.
*/
static int os2MutexInit(void){ return SQLITE_OK; }
static int os2MutexEnd(void){ return SQLITE_OK; }

/*
** The sqlite3_mutex_alloc() routine allocates a new
** mutex and returns a pointer to it.  If it returns NULL
** that means that a mutex could not be allocated. 
** SQLite will unwind its stack and return an error.  The argument
** to sqlite3_mutex_alloc() is one of these integer constants:
**
** <ul>
** <li>  SQLITE_MUTEX_FAST
** <li>  SQLITE_MUTEX_RECURSIVE
** <li>  SQLITE_MUTEX_STATIC_MASTER
** <li>  SQLITE_MUTEX_STATIC_MEM
** <li>  SQLITE_MUTEX_STATIC_MEM2
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_LRU2
** </ul>
**
** The first two constants cause sqlite3_mutex_alloc() to create
** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
** not want to.  But SQLite will only request a recursive mutex in
** cases where it really needs one.  If a faster non-recursive mutex
** implementation is available on the host platform, the mutex subsystem
** might return such a mutex in response to SQLITE_MUTEX_FAST.
**
** The other allowed parameters to sqlite3_mutex_alloc() each return
** a pointer to a static preexisting mutex.  Six static mutexes are
** used by the current version of SQLite.  Future versions of SQLite
** may add additional static mutexes.  Static mutexes are for internal
** use by SQLite only.  Applications that use SQLite mutexes should
** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or
** SQLITE_MUTEX_RECURSIVE.
**
** Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST
** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
** returns a different mutex on every call.  But for the static
** mutex types, the same mutex is returned on every call that has
** the same type number.
*/
static sqlite3_mutex *os2MutexAlloc(int iType){
  sqlite3_mutex *p = NULL;
  switch( iType ){
    case SQLITE_MUTEX_FAST:
    case SQLITE_MUTEX_RECURSIVE: {
      p = sqlite3MallocZero( sizeof(*p) );
      if( p ){
        p->id = iType;
        if( DosCreateMutexSem( 0, &p->mutex, 0, FALSE ) != NO_ERROR ){
          sqlite3_free( p );
          p = NULL;
        }
      }
      break;
    }
    default: {
      static volatile int isInit = 0;
      static sqlite3_mutex staticMutexes[6] = {
        SQLITE3_MUTEX_INITIALIZER,
        SQLITE3_MUTEX_INITIALIZER,
        SQLITE3_MUTEX_INITIALIZER,
        SQLITE3_MUTEX_INITIALIZER,
        SQLITE3_MUTEX_INITIALIZER,
        SQLITE3_MUTEX_INITIALIZER,
      };
      if ( !isInit ){
        APIRET rc;
        PTIB ptib;
        PPIB ppib;
        HMTX mutex;
        char name[32];
        DosGetInfoBlocks( &ptib, &ppib );
        sqlite3_snprintf( sizeof(name), name, "\\SEM32\\SQLITE%04x",
                          ppib->pib_ulpid );
        while( !isInit ){
          mutex = 0;
          rc = DosCreateMutexSem( name, &mutex, 0, FALSE);
          if( rc == NO_ERROR ){
            unsigned int i;
            if( !isInit ){
              for( i = 0; i < sizeof(staticMutexes)/sizeof(staticMutexes[0]); i++ ){
                DosCreateMutexSem( 0, &staticMutexes[i].mutex, 0, FALSE );
              }
              isInit = 1;
            }
            DosCloseMutexSem( mutex );
          }else if( rc == ERROR_DUPLICATE_NAME ){
            DosSleep( 1 );
          }else{
            return p;
          }
        }
      }
      assert( iType-2 >= 0 );
      assert( iType-2 < sizeof(staticMutexes)/sizeof(staticMutexes[0]) );
      p = &staticMutexes[iType-2];
      p->id = iType;
      break;
    }
  }
  return p;
}


/*
** This routine deallocates a previously allocated mutex.
** SQLite is careful to deallocate every mutex that it allocates.
*/
static void os2MutexFree(sqlite3_mutex *p){
#ifdef SQLITE_DEBUG
  TID tid;
  PID pid;
  ULONG ulCount;
  DosQueryMutexSem(p->mutex, &pid, &tid, &ulCount);
  assert( ulCount==0 );
  assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
#endif
  DosCloseMutexSem( p->mutex );
  sqlite3_free( p );
}

#ifdef SQLITE_DEBUG
/*
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
** intended for use inside assert() statements.
*/
static int os2MutexHeld(sqlite3_mutex *p){
  TID tid;
  PID pid;
  ULONG ulCount;
  PTIB ptib;
  DosQueryMutexSem(p->mutex, &pid, &tid, &ulCount);
  if( ulCount==0 || ( ulCount>1 && p->id!=SQLITE_MUTEX_RECURSIVE ) )
    return 0;
  DosGetInfoBlocks(&ptib, NULL);
  return tid==ptib->tib_ptib2->tib2_ultid;
}
static int os2MutexNotheld(sqlite3_mutex *p){
  TID tid;
  PID pid;
  ULONG ulCount;
  PTIB ptib;
  DosQueryMutexSem(p->mutex, &pid, &tid, &ulCount);
  if( ulCount==0 )
    return 1;
  DosGetInfoBlocks(&ptib, NULL);
  return tid!=ptib->tib_ptib2->tib2_ultid;
}
static void os2MutexTrace(sqlite3_mutex *p, char *pAction){
  TID   tid;
  PID   pid;
  ULONG ulCount;
  DosQueryMutexSem(p->mutex, &pid, &tid, &ulCount);
  printf("%s mutex %p (%d) with nRef=%ld\n", pAction, (void*)p, p->trace, ulCount);
}
#endif

/*
** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
** to enter a mutex.  If another thread is already within the mutex,
** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
** SQLITE_BUSY.  The sqlite3_mutex_try() interface returns SQLITE_OK
** upon successful entry.  Mutexes created using SQLITE_MUTEX_RECURSIVE can
** be entered multiple times by the same thread.  In such cases the,
** mutex must be exited an equal number of times before another thread
** can enter.  If the same thread tries to enter any other kind of mutex
** more than once, the behavior is undefined.
*/
static void os2MutexEnter(sqlite3_mutex *p){
  assert( p->id==SQLITE_MUTEX_RECURSIVE || os2MutexNotheld(p) );
  DosRequestMutexSem(p->mutex, SEM_INDEFINITE_WAIT);
#ifdef SQLITE_DEBUG
  if( p->trace ) os2MutexTrace(p, "enter");
#endif
}
static int os2MutexTry(sqlite3_mutex *p){
  int rc = SQLITE_BUSY;
  assert( p->id==SQLITE_MUTEX_RECURSIVE || os2MutexNotheld(p) );
  if( DosRequestMutexSem(p->mutex, SEM_IMMEDIATE_RETURN) == NO_ERROR ) {
    rc = SQLITE_OK;
#ifdef SQLITE_DEBUG
    if( p->trace ) os2MutexTrace(p, "try");
#endif
  }
  return rc;
}

/*
** The sqlite3_mutex_leave() routine exits a mutex that was
** previously entered by the same thread.  The behavior
** is undefined if the mutex is not currently entered or
** is not currently allocated.  SQLite will never do either.
*/
static void os2MutexLeave(sqlite3_mutex *p){
  assert( os2MutexHeld(p) );
  DosReleaseMutexSem(p->mutex);
#ifdef SQLITE_DEBUG
  if( p->trace ) os2MutexTrace(p, "leave");
#endif
}

sqlite3_mutex_methods const *sqlite3DefaultMutex(void){
  static const sqlite3_mutex_methods sMutex = {
    os2MutexInit,
    os2MutexEnd,
    os2MutexAlloc,
    os2MutexFree,
    os2MutexEnter,
    os2MutexTry,
    os2MutexLeave,
#ifdef SQLITE_DEBUG
    os2MutexHeld,
    os2MutexNotheld
#else
    0,
    0
#endif
  };

  return &sMutex;
}
#endif /* SQLITE_MUTEX_OS2 */

/* As winMutexInit() and winMutexEnd() are called as part
** of the sqlite3_initialize and sqlite3_shutdown()
** processing, the "interlocked" magic is probably not
** strictly necessary.
*/
static long winMutex_lock = 0;

extern void sqlite3_win32_sleep(DWORD milliseconds); /* os_win.c */

static int winMutexInit(void){ 
  /* The first to increment to 1 does actual initialization */
  if( InterlockedCompareExchange(&winMutex_lock, 1, 0)==0 ){
    int i;
    for(i=0; i<ArraySize(winMutex_staticMutexes); i++){
#if SQLITE_OS_WINRT

*/
#ifndef _SQLITE_OS_H_
#define _SQLITE_OS_H_

/*
** Figure out if we are dealing with Unix, Windows, or some other
** operating system.  After the following block of preprocess macros,
** all of SQLITE_OS_UNIX, SQLITE_OS_WIN, SQLITE_OS_OS2, and SQLITE_OS_OTHER 
** will defined to either 1 or 0.  One of the four will be 1.  The other 
** three will be 0.
*/
#if defined(SQLITE_OS_OTHER)
# if SQLITE_OS_OTHER==1
#   undef SQLITE_OS_UNIX
#   define SQLITE_OS_UNIX 0
#   undef SQLITE_OS_WIN
#   define SQLITE_OS_WIN 0
#   undef SQLITE_OS_OS2
#   define SQLITE_OS_OS2 0
# else
#   undef SQLITE_OS_OTHER
# endif
#endif
#if !defined(SQLITE_OS_UNIX) && !defined(SQLITE_OS_OTHER)
# define SQLITE_OS_OTHER 0
# ifndef SQLITE_OS_WIN
#   if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || defined(__MINGW32__) || defined(__BORLANDC__)
#     define SQLITE_OS_WIN 1
#     define SQLITE_OS_UNIX 0
#     define SQLITE_OS_OS2 0
#   elif defined(__EMX__) || defined(_OS2) || defined(OS2) || defined(_OS2_) || defined(__OS2__)
#     define SQLITE_OS_WIN 0
#     define SQLITE_OS_UNIX 0
#     define SQLITE_OS_OS2 1
#   else
#     define SQLITE_OS_WIN 0
#     define SQLITE_OS_UNIX 1
#     define SQLITE_OS_OS2 0
#  endif
# else
#  define SQLITE_OS_UNIX 0
#  define SQLITE_OS_OS2 0
# endif
#else
# ifndef SQLITE_OS_WIN
#  define SQLITE_OS_WIN 0
# endif
#endif

#if SQLITE_OS_WIN
# include <windows.h>
#endif

#if SQLITE_OS_OS2
# if (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3) && defined(OS2_HIGH_MEMORY)
#  include <os2safe.h> /* has to be included before os2.h for linking to work */
# endif
# define INCL_DOSDATETIME
# define INCL_DOSFILEMGR
# define INCL_DOSERRORS
# define INCL_DOSMISC
# define INCL_DOSPROCESS
# define INCL_DOSMODULEMGR
# define INCL_DOSSEMAPHORES
# include <os2.h>
# include <uconv.h>
#endif

/*
** Determine if we are dealing with Windows NT.
**
** We ought to be able to determine if we are compiling for win98 or winNT
** using the _WIN32_WINNT macro as follows:
**
** #if defined(_WIN32_WINNT)

#if defined(_WIN32_WCE)
# define SQLITE_OS_WINCE 1
#else
# define SQLITE_OS_WINCE 0
#endif

/*
** Determine if we are dealing with WindowsRT (Metro) as this has a different and
** incompatible API from win32.
*/
#if !defined(SQLITE_OS_WINRT)
# define SQLITE_OS_WINRT 0
#endif

/*
** When compiled for WinCE or WinRT, there is no concept of the current

/*
** 2006 Feb 14
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains code that is specific to OS/2.
*/

#include "sqliteInt.h"

#if SQLITE_OS_OS2

/*
** A Note About Memory Allocation:
**
** This driver uses malloc()/free() directly rather than going through
** the SQLite-wrappers sqlite3_malloc()/sqlite3_free().  Those wrappers
** are designed for use on embedded systems where memory is scarce and
** malloc failures happen frequently.  OS/2 does not typically run on
** embedded systems, and when it does the developers normally have bigger
** problems to worry about than running out of memory.  So there is not
** a compelling need to use the wrappers.
**
** But there is a good reason to not use the wrappers.  If we use the
** wrappers then we will get simulated malloc() failures within this
** driver.  And that causes all kinds of problems for our tests.  We
** could enhance SQLite to deal with simulated malloc failures within
** the OS driver, but the code to deal with those failure would not
** be exercised on Linux (which does not need to malloc() in the driver)
** and so we would have difficulty writing coverage tests for that
** code.  Better to leave the code out, we think.
**
** The point of this discussion is as follows:  When creating a new
** OS layer for an embedded system, if you use this file as an example,
** avoid the use of malloc()/free().  Those routines work ok on OS/2
** desktops but not so well in embedded systems.
*/

/*
** Macros used to determine whether or not to use threads.
*/
#if defined(SQLITE_THREADSAFE) && SQLITE_THREADSAFE
# define SQLITE_OS2_THREADS 1
#endif

/*
** Include code that is common to all os_*.c files
*/
#include "os_common.h"

/* Forward references */
typedef struct os2File os2File;         /* The file structure */
typedef struct os2ShmNode os2ShmNode;   /* A shared descritive memory node */
typedef struct os2ShmLink os2ShmLink;   /* A connection to shared-memory */

/*
** The os2File structure is subclass of sqlite3_file specific for the OS/2
** protability layer.
*/
struct os2File {
  const sqlite3_io_methods *pMethod;  /* Always the first entry */
  HFILE h;                  /* Handle for accessing the file */
  int flags;                /* Flags provided to os2Open() */
  int locktype;             /* Type of lock currently held on this file */
  int szChunk;              /* Chunk size configured by FCNTL_CHUNK_SIZE */
  char *zFullPathCp;        /* Full path name of this file */
  os2ShmLink *pShmLink;     /* Instance of shared memory on this file */
};

#define LOCK_TIMEOUT 10L /* the default locking timeout */

/*
** Missing from some versions of the OS/2 toolkit -
** used to allocate from high memory if possible
*/
#ifndef OBJ_ANY
# define OBJ_ANY 0x00000400
#endif

/*****************************************************************************
** The next group of routines implement the I/O methods specified
** by the sqlite3_io_methods object.
******************************************************************************/

/*
** Close a file.
*/
static int os2Close( sqlite3_file *id ){
  APIRET rc;
  os2File *pFile = (os2File*)id;

  assert( id!=0 );
  OSTRACE(( "CLOSE %d (%s)\n", pFile->h, pFile->zFullPathCp ));

  rc = DosClose( pFile->h );

  if( pFile->flags & SQLITE_OPEN_DELETEONCLOSE )
    DosForceDelete( (PSZ)pFile->zFullPathCp );

  free( pFile->zFullPathCp );
  pFile->zFullPathCp = NULL;
  pFile->locktype = NO_LOCK;
  pFile->h = (HFILE)-1;
  pFile->flags = 0;

  OpenCounter( -1 );
  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
}

/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
static int os2Read(
  sqlite3_file *id,               /* File to read from */
  void *pBuf,                     /* Write content into this buffer */
  int amt,                        /* Number of bytes to read */
  sqlite3_int64 offset            /* Begin reading at this offset */
){
  ULONG fileLocation = 0L;
  ULONG got;
  os2File *pFile = (os2File*)id;
  assert( id!=0 );
  SimulateIOError( return SQLITE_IOERR_READ );
  OSTRACE(( "READ %d lock=%d\n", pFile->h, pFile->locktype ));
  if( DosSetFilePtr(pFile->h, offset, FILE_BEGIN, &fileLocation) != NO_ERROR ){
    return SQLITE_IOERR;
  }
  if( DosRead( pFile->h, pBuf, amt, &got ) != NO_ERROR ){
    return SQLITE_IOERR_READ;
  }
  if( got == (ULONG)amt )
    return SQLITE_OK;
  else {
    /* Unread portions of the input buffer must be zero-filled */
    memset(&((char*)pBuf)[got], 0, amt-got);
    return SQLITE_IOERR_SHORT_READ;
  }
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
static int os2Write(
  sqlite3_file *id,               /* File to write into */
  const void *pBuf,               /* The bytes to be written */
  int amt,                        /* Number of bytes to write */
  sqlite3_int64 offset            /* Offset into the file to begin writing at */
){
  ULONG fileLocation = 0L;
  APIRET rc = NO_ERROR;
  ULONG wrote;
  os2File *pFile = (os2File*)id;
  assert( id!=0 );
  SimulateIOError( return SQLITE_IOERR_WRITE );
  SimulateDiskfullError( return SQLITE_FULL );
  OSTRACE(( "WRITE %d lock=%d\n", pFile->h, pFile->locktype ));
  if( DosSetFilePtr(pFile->h, offset, FILE_BEGIN, &fileLocation) != NO_ERROR ){
    return SQLITE_IOERR;
  }
  assert( amt>0 );
  while( amt > 0 &&
         ( rc = DosWrite( pFile->h, (PVOID)pBuf, amt, &wrote ) ) == NO_ERROR &&
         wrote > 0
  ){
    amt -= wrote;
    pBuf = &((char*)pBuf)[wrote];
  }

  return ( rc != NO_ERROR || amt > (int)wrote ) ? SQLITE_FULL : SQLITE_OK;
}

/*
** Truncate an open file to a specified size
*/
static int os2Truncate( sqlite3_file *id, i64 nByte ){
  APIRET rc;
  os2File *pFile = (os2File*)id;
  assert( id!=0 );
  OSTRACE(( "TRUNCATE %d %lld\n", pFile->h, nByte ));
  SimulateIOError( return SQLITE_IOERR_TRUNCATE );

  /* If the user has configured a chunk-size for this file, truncate the
  ** file so that it consists of an integer number of chunks (i.e. the
  ** actual file size after the operation may be larger than the requested
  ** size).
  */
  if( pFile->szChunk ){
    nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
  }
  
  rc = DosSetFileSize( pFile->h, nByte );
  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR_TRUNCATE;
}

#ifdef SQLITE_TEST
/*
** Count the number of fullsyncs and normal syncs.  This is used to test
** that syncs and fullsyncs are occuring at the right times.
*/
int sqlite3_sync_count = 0;
int sqlite3_fullsync_count = 0;
#endif

/*
** Make sure all writes to a particular file are committed to disk.
*/
static int os2Sync( sqlite3_file *id, int flags ){
  os2File *pFile = (os2File*)id;
  OSTRACE(( "SYNC %d lock=%d\n", pFile->h, pFile->locktype ));
#ifdef SQLITE_TEST
  if( flags & SQLITE_SYNC_FULL){
    sqlite3_fullsync_count++;
  }
  sqlite3_sync_count++;
#endif
  /* If we compiled with the SQLITE_NO_SYNC flag, then syncing is a
  ** no-op
  */
#ifdef SQLITE_NO_SYNC
  UNUSED_PARAMETER(pFile);
  return SQLITE_OK;
#else
  return DosResetBuffer( pFile->h ) == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
#endif
}

/*
** Determine the current size of a file in bytes
*/
static int os2FileSize( sqlite3_file *id, sqlite3_int64 *pSize ){
  APIRET rc = NO_ERROR;
  FILESTATUS3 fsts3FileInfo;
  memset(&fsts3FileInfo, 0, sizeof(fsts3FileInfo));
  assert( id!=0 );
  SimulateIOError( return SQLITE_IOERR_FSTAT );
  rc = DosQueryFileInfo( ((os2File*)id)->h, FIL_STANDARD, &fsts3FileInfo, sizeof(FILESTATUS3) );
  if( rc == NO_ERROR ){
    *pSize = fsts3FileInfo.cbFile;
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR_FSTAT;
  }
}

/*
** Acquire a reader lock.
*/
static int getReadLock( os2File *pFile ){
  FILELOCK  LockArea,
            UnlockArea;
  APIRET res;
  memset(&LockArea, 0, sizeof(LockArea));
  memset(&UnlockArea, 0, sizeof(UnlockArea));
  LockArea.lOffset = SHARED_FIRST;
  LockArea.lRange = SHARED_SIZE;
  UnlockArea.lOffset = 0L;
  UnlockArea.lRange = 0L;
  res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 1L );
  OSTRACE(( "GETREADLOCK %d res=%d\n", pFile->h, res ));
  return res;
}

/*
** Undo a readlock
*/
static int unlockReadLock( os2File *id ){
  FILELOCK  LockArea,
            UnlockArea;
  APIRET res;
  memset(&LockArea, 0, sizeof(LockArea));
  memset(&UnlockArea, 0, sizeof(UnlockArea));
  LockArea.lOffset = 0L;
  LockArea.lRange = 0L;
  UnlockArea.lOffset = SHARED_FIRST;
  UnlockArea.lRange = SHARED_SIZE;
  res = DosSetFileLocks( id->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 1L );
  OSTRACE(( "UNLOCK-READLOCK file handle=%d res=%d?\n", id->h, res ));
  return res;
}

/*
** Lock the file with the lock specified by parameter locktype - one
** of the following:
**
**     (1) SHARED_LOCK
**     (2) RESERVED_LOCK
**     (3) PENDING_LOCK
**     (4) EXCLUSIVE_LOCK
**
** Sometimes when requesting one lock state, additional lock states
** are inserted in between.  The locking might fail on one of the later
** transitions leaving the lock state different from what it started but
** still short of its goal.  The following chart shows the allowed
** transitions and the inserted intermediate states:
**
**    UNLOCKED -> SHARED
**    SHARED -> RESERVED
**    SHARED -> (PENDING) -> EXCLUSIVE
**    RESERVED -> (PENDING) -> EXCLUSIVE
**    PENDING -> EXCLUSIVE
**
** This routine will only increase a lock.  The os2Unlock() routine
** erases all locks at once and returns us immediately to locking level 0.
** It is not possible to lower the locking level one step at a time.  You
** must go straight to locking level 0.
*/
static int os2Lock( sqlite3_file *id, int locktype ){
  int rc = SQLITE_OK;       /* Return code from subroutines */
  APIRET res = NO_ERROR;    /* Result of an OS/2 lock call */
  int newLocktype;       /* Set pFile->locktype to this value before exiting */
  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
  FILELOCK  LockArea,
            UnlockArea;
  os2File *pFile = (os2File*)id;
  memset(&LockArea, 0, sizeof(LockArea));
  memset(&UnlockArea, 0, sizeof(UnlockArea));
  assert( pFile!=0 );
  OSTRACE(( "LOCK %d %d was %d\n", pFile->h, locktype, pFile->locktype ));

  /* If there is already a lock of this type or more restrictive on the
  ** os2File, do nothing. Don't use the end_lock: exit path, as
  ** sqlite3_mutex_enter() hasn't been called yet.
  */
  if( pFile->locktype>=locktype ){
    OSTRACE(( "LOCK %d %d ok (already held)\n", pFile->h, locktype ));
    return SQLITE_OK;
  }

  /* Make sure the locking sequence is correct
  */
  assert( pFile->locktype!=NO_LOCK || locktype==SHARED_LOCK );
  assert( locktype!=PENDING_LOCK );
  assert( locktype!=RESERVED_LOCK || pFile->locktype==SHARED_LOCK );

  /* Lock the PENDING_LOCK byte if we need to acquire a PENDING lock or
  ** a SHARED lock.  If we are acquiring a SHARED lock, the acquisition of
  ** the PENDING_LOCK byte is temporary.
  */
  newLocktype = pFile->locktype;
  if( pFile->locktype==NO_LOCK
      || (locktype==EXCLUSIVE_LOCK && pFile->locktype==RESERVED_LOCK)
  ){
    LockArea.lOffset = PENDING_BYTE;
    LockArea.lRange = 1L;
    UnlockArea.lOffset = 0L;
    UnlockArea.lRange = 0L;

    /* wait longer than LOCK_TIMEOUT here not to have to try multiple times */
    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, 100L, 0L );
    if( res == NO_ERROR ){
      gotPendingLock = 1;
      OSTRACE(( "LOCK %d pending lock boolean set.  res=%d\n", pFile->h, res ));
    }
  }

  /* Acquire a shared lock
  */
  if( locktype==SHARED_LOCK && res == NO_ERROR ){
    assert( pFile->locktype==NO_LOCK );
    res = getReadLock(pFile);
    if( res == NO_ERROR ){
      newLocktype = SHARED_LOCK;
    }
    OSTRACE(( "LOCK %d acquire shared lock. res=%d\n", pFile->h, res ));
  }

  /* Acquire a RESERVED lock
  */
  if( locktype==RESERVED_LOCK && res == NO_ERROR ){
    assert( pFile->locktype==SHARED_LOCK );
    LockArea.lOffset = RESERVED_BYTE;
    LockArea.lRange = 1L;
    UnlockArea.lOffset = 0L;
    UnlockArea.lRange = 0L;
    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
    if( res == NO_ERROR ){
      newLocktype = RESERVED_LOCK;
    }
    OSTRACE(( "LOCK %d acquire reserved lock. res=%d\n", pFile->h, res ));
  }

  /* Acquire a PENDING lock
  */
  if( locktype==EXCLUSIVE_LOCK && res == NO_ERROR ){
    newLocktype = PENDING_LOCK;
    gotPendingLock = 0;
    OSTRACE(( "LOCK %d acquire pending lock. pending lock boolean unset.\n",
               pFile->h ));
  }

  /* Acquire an EXCLUSIVE lock
  */
  if( locktype==EXCLUSIVE_LOCK && res == NO_ERROR ){
    assert( pFile->locktype>=SHARED_LOCK );
    res = unlockReadLock(pFile);
    OSTRACE(( "unreadlock = %d\n", res ));
    LockArea.lOffset = SHARED_FIRST;
    LockArea.lRange = SHARED_SIZE;
    UnlockArea.lOffset = 0L;
    UnlockArea.lRange = 0L;
    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
    if( res == NO_ERROR ){
      newLocktype = EXCLUSIVE_LOCK;
    }else{
      OSTRACE(( "OS/2 error-code = %d\n", res ));
      getReadLock(pFile);
    }
    OSTRACE(( "LOCK %d acquire exclusive lock.  res=%d\n", pFile->h, res ));
  }

  /* If we are holding a PENDING lock that ought to be released, then
  ** release it now.
  */
  if( gotPendingLock && locktype==SHARED_LOCK ){
    int r;
    LockArea.lOffset = 0L;
    LockArea.lRange = 0L;
    UnlockArea.lOffset = PENDING_BYTE;
    UnlockArea.lRange = 1L;
    r = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
    OSTRACE(( "LOCK %d unlocking pending/is shared. r=%d\n", pFile->h, r ));
  }

  /* Update the state of the lock has held in the file descriptor then
  ** return the appropriate result code.
  */
  if( res == NO_ERROR ){
    rc = SQLITE_OK;
  }else{
    OSTRACE(( "LOCK FAILED %d trying for %d but got %d\n", pFile->h,
              locktype, newLocktype ));
    rc = SQLITE_BUSY;
  }
  pFile->locktype = newLocktype;
  OSTRACE(( "LOCK %d now %d\n", pFile->h, pFile->locktype ));
  return rc;
}

/*
** This routine checks if there is a RESERVED lock held on the specified
** file by this or any other process. If such a lock is held, return
** non-zero, otherwise zero.
*/
static int os2CheckReservedLock( sqlite3_file *id, int *pOut ){
  int r = 0;
  os2File *pFile = (os2File*)id;
  assert( pFile!=0 );
  if( pFile->locktype>=RESERVED_LOCK ){
    r = 1;
    OSTRACE(( "TEST WR-LOCK %d %d (local)\n", pFile->h, r ));
  }else{
    FILELOCK  LockArea,
              UnlockArea;
    APIRET rc = NO_ERROR;
    memset(&LockArea, 0, sizeof(LockArea));
    memset(&UnlockArea, 0, sizeof(UnlockArea));
    LockArea.lOffset = RESERVED_BYTE;
    LockArea.lRange = 1L;
    UnlockArea.lOffset = 0L;
    UnlockArea.lRange = 0L;
    rc = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
    OSTRACE(( "TEST WR-LOCK %d lock reserved byte rc=%d\n", pFile->h, rc ));
    if( rc == NO_ERROR ){
      APIRET rcu = NO_ERROR; /* return code for unlocking */
      LockArea.lOffset = 0L;
      LockArea.lRange = 0L;
      UnlockArea.lOffset = RESERVED_BYTE;
      UnlockArea.lRange = 1L;
      rcu = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
      OSTRACE(( "TEST WR-LOCK %d unlock reserved byte r=%d\n", pFile->h, rcu ));
    }
    r = !(rc == NO_ERROR);
    OSTRACE(( "TEST WR-LOCK %d %d (remote)\n", pFile->h, r ));
  }
  *pOut = r;
  return SQLITE_OK;
}

/*
** Lower the locking level on file descriptor id to locktype.  locktype
** must be either NO_LOCK or SHARED_LOCK.
**
** If the locking level of the file descriptor is already at or below
** the requested locking level, this routine is a no-op.
**
** It is not possible for this routine to fail if the second argument
** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
** might return SQLITE_IOERR;
*/
static int os2Unlock( sqlite3_file *id, int locktype ){
  int type;
  os2File *pFile = (os2File*)id;
  APIRET rc = SQLITE_OK;
  APIRET res = NO_ERROR;
  FILELOCK  LockArea,
            UnlockArea;
  memset(&LockArea, 0, sizeof(LockArea));
  memset(&UnlockArea, 0, sizeof(UnlockArea));
  assert( pFile!=0 );
  assert( locktype<=SHARED_LOCK );
  OSTRACE(( "UNLOCK %d to %d was %d\n", pFile->h, locktype, pFile->locktype ));
  type = pFile->locktype;
  if( type>=EXCLUSIVE_LOCK ){
    LockArea.lOffset = 0L;
    LockArea.lRange = 0L;
    UnlockArea.lOffset = SHARED_FIRST;
    UnlockArea.lRange = SHARED_SIZE;
    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
    OSTRACE(( "UNLOCK %d exclusive lock res=%d\n", pFile->h, res ));
    if( locktype==SHARED_LOCK && getReadLock(pFile) != NO_ERROR ){
      /* This should never happen.  We should always be able to
      ** reacquire the read lock */
      OSTRACE(( "UNLOCK %d to %d getReadLock() failed\n", pFile->h, locktype ));
      rc = SQLITE_IOERR_UNLOCK;
    }
  }
  if( type>=RESERVED_LOCK ){
    LockArea.lOffset = 0L;
    LockArea.lRange = 0L;
    UnlockArea.lOffset = RESERVED_BYTE;
    UnlockArea.lRange = 1L;
    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
    OSTRACE(( "UNLOCK %d reserved res=%d\n", pFile->h, res ));
  }
  if( locktype==NO_LOCK && type>=SHARED_LOCK ){
    res = unlockReadLock(pFile);
    OSTRACE(( "UNLOCK %d is %d want %d res=%d\n",
              pFile->h, type, locktype, res ));
  }
  if( type>=PENDING_LOCK ){
    LockArea.lOffset = 0L;
    LockArea.lRange = 0L;
    UnlockArea.lOffset = PENDING_BYTE;
    UnlockArea.lRange = 1L;
    res = DosSetFileLocks( pFile->h, &UnlockArea, &LockArea, LOCK_TIMEOUT, 0L );
    OSTRACE(( "UNLOCK %d pending res=%d\n", pFile->h, res ));
  }
  pFile->locktype = locktype;
  OSTRACE(( "UNLOCK %d now %d\n", pFile->h, pFile->locktype ));
  return rc;
}

/*
** Control and query of the open file handle.
*/
static int os2FileControl(sqlite3_file *id, int op, void *pArg){
  switch( op ){
    case SQLITE_FCNTL_LOCKSTATE: {
      *(int*)pArg = ((os2File*)id)->locktype;
      OSTRACE(( "FCNTL_LOCKSTATE %d lock=%d\n",
                ((os2File*)id)->h, ((os2File*)id)->locktype ));
      return SQLITE_OK;
    }
    case SQLITE_FCNTL_CHUNK_SIZE: {
      ((os2File*)id)->szChunk = *(int*)pArg;
      return SQLITE_OK;
    }
    case SQLITE_FCNTL_SIZE_HINT: {
      sqlite3_int64 sz = *(sqlite3_int64*)pArg;
      SimulateIOErrorBenign(1);
      os2Truncate(id, sz);
      SimulateIOErrorBenign(0);
      return SQLITE_OK;
    }
    case SQLITE_FCNTL_SYNC_OMITTED: {
      return SQLITE_OK;
    }
  }
  return SQLITE_NOTFOUND;
}

/*
** Return the sector size in bytes of the underlying block device for
** the specified file. This is almost always 512 bytes, but may be
** larger for some devices.
**
** SQLite code assumes this function cannot fail. It also assumes that
** if two files are created in the same file-system directory (i.e.
** a database and its journal file) that the sector size will be the
** same for both.
*/
static int os2SectorSize(sqlite3_file *id){
  UNUSED_PARAMETER(id);
  return SQLITE_DEFAULT_SECTOR_SIZE;
}

/*
** Return a vector of device characteristics.
*/
static int os2DeviceCharacteristics(sqlite3_file *id){
  UNUSED_PARAMETER(id);
  return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN;
}


/*
** Character set conversion objects used by conversion routines.
*/
static UconvObject ucUtf8 = NULL; /* convert between UTF-8 and UCS-2 */
static UconvObject uclCp = NULL;  /* convert between local codepage and UCS-2 */

/*
** Helper function to initialize the conversion objects from and to UTF-8.
*/
static void initUconvObjects( void ){
  if( UniCreateUconvObject( UTF_8, &ucUtf8 ) != ULS_SUCCESS )
    ucUtf8 = NULL;
  if ( UniCreateUconvObject( (UniChar *)L"@path=yes", &uclCp ) != ULS_SUCCESS )
    uclCp = NULL;
}

/*
** Helper function to free the conversion objects from and to UTF-8.
*/
static void freeUconvObjects( void ){
  if ( ucUtf8 )
    UniFreeUconvObject( ucUtf8 );
  if ( uclCp )
    UniFreeUconvObject( uclCp );
  ucUtf8 = NULL;
  uclCp = NULL;
}

/*
** Helper function to convert UTF-8 filenames to local OS/2 codepage.
** The two-step process: first convert the incoming UTF-8 string
** into UCS-2 and then from UCS-2 to the current codepage.
** The returned char pointer has to be freed.
*/
static char *convertUtf8PathToCp( const char *in ){
  UniChar tempPath[CCHMAXPATH];
  char *out = (char *)calloc( CCHMAXPATH, 1 );

  if( !out )
    return NULL;

  if( !ucUtf8 || !uclCp )
    initUconvObjects();

  /* determine string for the conversion of UTF-8 which is CP1208 */
  if( UniStrToUcs( ucUtf8, tempPath, (char *)in, CCHMAXPATH ) != ULS_SUCCESS )
    return out; /* if conversion fails, return the empty string */

  /* conversion for current codepage which can be used for paths */
  UniStrFromUcs( uclCp, out, tempPath, CCHMAXPATH );

  return out;
}

/*
** Helper function to convert filenames from local codepage to UTF-8.
** The two-step process: first convert the incoming codepage-specific
** string into UCS-2 and then from UCS-2 to the codepage of UTF-8.
** The returned char pointer has to be freed.
**
** This function is non-static to be able to use this in shell.c and
** similar applications that take command line arguments.
*/
char *convertCpPathToUtf8( const char *in ){
  UniChar tempPath[CCHMAXPATH];
  char *out = (char *)calloc( CCHMAXPATH, 1 );

  if( !out )
    return NULL;

  if( !ucUtf8 || !uclCp )
    initUconvObjects();

  /* conversion for current codepage which can be used for paths */
  if( UniStrToUcs( uclCp, tempPath, (char *)in, CCHMAXPATH ) != ULS_SUCCESS )
    return out; /* if conversion fails, return the empty string */

  /* determine string for the conversion of UTF-8 which is CP1208 */
  UniStrFromUcs( ucUtf8, out, tempPath, CCHMAXPATH );

  return out;
}


#ifndef SQLITE_OMIT_WAL

/*
** Use main database file for interprocess locking. If un-defined
** a separate file is created for this purpose. The file will be
** used only to set file locks. There will be no data written to it.
*/
#define SQLITE_OS2_NO_WAL_LOCK_FILE     

#if 0
static void _ERR_TRACE( const char *fmt, ... ) {
  va_list  ap;
  va_start(ap, fmt);
  vfprintf(stderr, fmt, ap);
  fflush(stderr);
}
#define ERR_TRACE(rc, msg)        \
        if( (rc) != SQLITE_OK ) _ERR_TRACE msg;
#else
#define ERR_TRACE(rc, msg)
#endif

/*
** Helper functions to obtain and relinquish the global mutex. The
** global mutex is used to protect os2ShmNodeList.
**
** Function os2ShmMutexHeld() is used to assert() that the global mutex 
** is held when required. This function is only used as part of assert() 
** statements. e.g.
**
**   os2ShmEnterMutex()
**     assert( os2ShmMutexHeld() );
**   os2ShmLeaveMutex()
*/
static void os2ShmEnterMutex(void){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
static void os2ShmLeaveMutex(void){
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
#ifdef SQLITE_DEBUG
static int os2ShmMutexHeld(void) {
  return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
int GetCurrentProcessId(void) {
  PPIB pib;
  DosGetInfoBlocks(NULL, &pib);
  return (int)pib->pib_ulpid;
}
#endif

/*
** Object used to represent a the shared memory area for a single log file.
** When multiple threads all reference the same log-summary, each thread has
** its own os2File object, but they all point to a single instance of this 
** object.  In other words, each log-summary is opened only once per process.
**
** os2ShmMutexHeld() must be true when creating or destroying
** this object or while reading or writing the following fields:
**
**      nRef
**      pNext 
**
** The following fields are read-only after the object is created:
** 
**      szRegion
**      hLockFile
**      shmBaseName
**
** Either os2ShmNode.mutex must be held or os2ShmNode.nRef==0 and
** os2ShmMutexHeld() is true when reading or writing any other field
** in this structure.
**
*/
struct os2ShmNode {
  sqlite3_mutex *mutex;      /* Mutex to access this object */
  os2ShmNode *pNext;         /* Next in list of all os2ShmNode objects */

  int szRegion;              /* Size of shared-memory regions */

  int nRegion;               /* Size of array apRegion */
  void **apRegion;           /* Array of pointers to shared-memory regions */

  int nRef;                  /* Number of os2ShmLink objects pointing to this */
  os2ShmLink *pFirst;        /* First os2ShmLink object pointing to this */

  HFILE hLockFile;           /* File used for inter-process memory locking */
  char shmBaseName[1];       /* Name of the memory object !!! must last !!! */
};


/*
** Structure used internally by this VFS to record the state of an
** open shared memory connection.
**
** The following fields are initialized when this object is created and
** are read-only thereafter:
**
**    os2Shm.pShmNode
**    os2Shm.id
**
** All other fields are read/write.  The os2Shm.pShmNode->mutex must be held
** while accessing any read/write fields.
*/
struct os2ShmLink {
  os2ShmNode *pShmNode;      /* The underlying os2ShmNode object */
  os2ShmLink *pNext;         /* Next os2Shm with the same os2ShmNode */
  u32 sharedMask;            /* Mask of shared locks held */
  u32 exclMask;              /* Mask of exclusive locks held */
#ifdef SQLITE_DEBUG
  u8 id;                     /* Id of this connection with its os2ShmNode */
#endif
};


/*
** A global list of all os2ShmNode objects.
**
** The os2ShmMutexHeld() must be true while reading or writing this list.
*/
static os2ShmNode *os2ShmNodeList = NULL;

/*
** Constants used for locking
*/
#ifdef  SQLITE_OS2_NO_WAL_LOCK_FILE
#define OS2_SHM_BASE   (PENDING_BYTE + 0x10000)         /* first lock byte */
#else
#define OS2_SHM_BASE   ((22+SQLITE_SHM_NLOCK)*4)        /* first lock byte */
#endif

#define OS2_SHM_DMS    (OS2_SHM_BASE+SQLITE_SHM_NLOCK)  /* deadman switch */

/*
** Apply advisory locks for all n bytes beginning at ofst.
*/
#define _SHM_UNLCK  1   /* no lock */
#define _SHM_RDLCK  2   /* shared lock, no wait */
#define _SHM_WRLCK  3   /* exlusive lock, no wait */
#define _SHM_WRLCK_WAIT 4 /* exclusive lock, wait */
static int os2ShmSystemLock(
  os2ShmNode *pNode,    /* Apply locks to this open shared-memory segment */
  int lockType,         /* _SHM_UNLCK, _SHM_RDLCK, _SHM_WRLCK or _SHM_WRLCK_WAIT */
  int ofst,             /* Offset to first byte to be locked/unlocked */
  int nByte             /* Number of bytes to lock or unlock */
){
  APIRET rc;
  FILELOCK area;
  ULONG mode, timeout;

  /* Access to the os2ShmNode object is serialized by the caller */
  assert( sqlite3_mutex_held(pNode->mutex) || pNode->nRef==0 );

  mode = 1;     /* shared lock */
  timeout = 0;  /* no wait */
  area.lOffset = ofst;
  area.lRange = nByte;

  switch( lockType ) {
    case _SHM_WRLCK_WAIT:
      timeout = (ULONG)-1;      /* wait forever */
    case _SHM_WRLCK:
      mode = 0;                 /* exclusive lock */
    case _SHM_RDLCK:
      rc = DosSetFileLocks(pNode->hLockFile, 
                           NULL, &area, timeout, mode);
      break;
    /* case _SHM_UNLCK: */
    default:
      rc = DosSetFileLocks(pNode->hLockFile, 
                           &area, NULL, 0, 0);
      break;
  }
                          
  OSTRACE(("SHM-LOCK %d %s %s 0x%08lx\n", 
           pNode->hLockFile,
           rc==SQLITE_OK ? "ok" : "failed",
           lockType==_SHM_UNLCK ? "Unlock" : "Lock",
           rc));

  ERR_TRACE(rc, ("os2ShmSystemLock: %d %s\n", rc, pNode->shmBaseName))

  return ( rc == 0 ) ?  SQLITE_OK : SQLITE_BUSY;
}

/*
** Find an os2ShmNode in global list or allocate a new one, if not found.
**
** This is not a VFS shared-memory method; it is a utility function called
** by VFS shared-memory methods.
*/
static int os2OpenSharedMemory( os2File *fd, int szRegion ) {
  os2ShmLink *pLink;
  os2ShmNode *pNode;
  int cbShmName, rc = SQLITE_OK;
  char shmName[CCHMAXPATH + 30];
#ifndef SQLITE_OS2_NO_WAL_LOCK_FILE
  ULONG action;
#endif
  
  /* We need some additional space at the end to append the region number */
  cbShmName = sprintf(shmName, "\\SHAREMEM\\%s", fd->zFullPathCp );
  if( cbShmName >= CCHMAXPATH-8 )
    return SQLITE_IOERR_SHMOPEN; 

  /* Replace colon in file name to form a valid shared memory name */
  shmName[10+1] = '!';

  /* Allocate link object (we free it later in case of failure) */
  pLink = sqlite3_malloc( sizeof(*pLink) );
  if( !pLink )
    return SQLITE_NOMEM;

  /* Access node list */
  os2ShmEnterMutex();

  /* Find node by it's shared memory base name */
  for( pNode = os2ShmNodeList; 
       pNode && stricmp(shmName, pNode->shmBaseName) != 0; 
       pNode = pNode->pNext )   ;

  /* Not found: allocate a new node */
  if( !pNode ) {
    pNode = sqlite3_malloc( sizeof(*pNode) + cbShmName );
    if( pNode ) {
      memset(pNode, 0, sizeof(*pNode) );
      pNode->szRegion = szRegion;
      pNode->hLockFile = (HFILE)-1;      
      strcpy(pNode->shmBaseName, shmName);

#ifdef SQLITE_OS2_NO_WAL_LOCK_FILE
      if( DosDupHandle(fd->h, &pNode->hLockFile) != 0 ) {
#else
      sprintf(shmName, "%s-lck", fd->zFullPathCp);
      if( DosOpen((PSZ)shmName, &pNode->hLockFile, &action, 0, FILE_NORMAL, 
                  OPEN_ACTION_OPEN_IF_EXISTS | OPEN_ACTION_CREATE_IF_NEW,
                  OPEN_ACCESS_READWRITE | OPEN_SHARE_DENYNONE | 
                  OPEN_FLAGS_NOINHERIT | OPEN_FLAGS_FAIL_ON_ERROR,
                  NULL) != 0 ) {
#endif
        sqlite3_free(pNode);  
        rc = SQLITE_IOERR;
      } else {
        pNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
        if( !pNode->mutex ) {
          sqlite3_free(pNode);  
          rc = SQLITE_NOMEM;
        }
      }   
    } else {
      rc = SQLITE_NOMEM;
    }
    
    if( rc == SQLITE_OK ) {
      pNode->pNext = os2ShmNodeList;
      os2ShmNodeList = pNode;
    } else {
      pNode = NULL;
    }
  } else if( pNode->szRegion != szRegion ) {
    rc = SQLITE_IOERR_SHMSIZE;
    pNode = NULL;
  }

  if( pNode ) {
    sqlite3_mutex_enter(pNode->mutex);

    memset(pLink, 0, sizeof(*pLink));

    pLink->pShmNode = pNode;
    pLink->pNext = pNode->pFirst;
    pNode->pFirst = pLink;
    pNode->nRef++;

    fd->pShmLink = pLink;

    sqlite3_mutex_leave(pNode->mutex);
    
  } else {
    /* Error occured. Free our link object. */
    sqlite3_free(pLink);  
  }

  os2ShmLeaveMutex();

  ERR_TRACE(rc, ("os2OpenSharedMemory: %d  %s\n", rc, fd->zFullPathCp))  
  
  return rc;
}

/*
** Purge the os2ShmNodeList list of all entries with nRef==0.
**
** This is not a VFS shared-memory method; it is a utility function called
** by VFS shared-memory methods.
*/
static void os2PurgeShmNodes( int deleteFlag ) {
  os2ShmNode *pNode;
  os2ShmNode **ppNode;

  os2ShmEnterMutex();
  
  ppNode = &os2ShmNodeList;

  while( *ppNode ) {
    pNode = *ppNode;

    if( pNode->nRef == 0 ) {
      *ppNode = pNode->pNext;   
     
      if( pNode->apRegion ) {
        /* Prevent other processes from resizing the shared memory */
        os2ShmSystemLock(pNode, _SHM_WRLCK_WAIT, OS2_SHM_DMS, 1);

        while( pNode->nRegion-- ) {
#ifdef SQLITE_DEBUG
          int rc = 
#endif          
          DosFreeMem(pNode->apRegion[pNode->nRegion]);

          OSTRACE(("SHM-PURGE pid-%d unmap region=%d %s\n",
                  (int)GetCurrentProcessId(), pNode->nRegion,
                  rc == 0 ? "ok" : "failed"));
        }

        /* Allow other processes to resize the shared memory */
        os2ShmSystemLock(pNode, _SHM_UNLCK, OS2_SHM_DMS, 1);

        sqlite3_free(pNode->apRegion);
      }  

      DosClose(pNode->hLockFile);
      
#ifndef SQLITE_OS2_NO_WAL_LOCK_FILE
      if( deleteFlag ) {
         char fileName[CCHMAXPATH];
         /* Skip "\\SHAREMEM\\" */
         sprintf(fileName, "%s-lck", pNode->shmBaseName + 10);
         /* restore colon */
         fileName[1] = ':';
         
         DosForceDelete(fileName); 
      }
#endif

      sqlite3_mutex_free(pNode->mutex);

      sqlite3_free(pNode);
      
    } else {
      ppNode = &pNode->pNext;
    }
  } 

  os2ShmLeaveMutex();
}

/*
** This function is called to obtain a pointer to region iRegion of the
** shared-memory associated with the database file id. Shared-memory regions
** are numbered starting from zero. Each shared-memory region is szRegion
** bytes in size.
**
** If an error occurs, an error code is returned and *pp is set to NULL.
**
** Otherwise, if the bExtend parameter is 0 and the requested shared-memory
** region has not been allocated (by any client, including one running in a
** separate process), then *pp is set to NULL and SQLITE_OK returned. If
** bExtend is non-zero and the requested shared-memory region has not yet
** been allocated, it is allocated by this function.
**
** If the shared-memory region has already been allocated or is allocated by
** this call as described above, then it is mapped into this processes
** address space (if it is not already), *pp is set to point to the mapped
** memory and SQLITE_OK returned.
*/
static int os2ShmMap(
  sqlite3_file *id,               /* Handle open on database file */
  int iRegion,                    /* Region to retrieve */
  int szRegion,                   /* Size of regions */
  int bExtend,                    /* True to extend block if necessary */
  void volatile **pp              /* OUT: Mapped memory */
){
  PVOID pvTemp;
  void **apRegion;
  os2ShmNode *pNode;
  int n, rc = SQLITE_OK;
  char shmName[CCHMAXPATH];
  os2File *pFile = (os2File*)id;
  
  *pp = NULL;

  if( !pFile->pShmLink )
    rc = os2OpenSharedMemory( pFile, szRegion );
  
  if( rc == SQLITE_OK ) {
    pNode = pFile->pShmLink->pShmNode ;
    
    sqlite3_mutex_enter(pNode->mutex);
    
    assert( szRegion==pNode->szRegion );

    /* Unmapped region ? */
    if( iRegion >= pNode->nRegion ) {
      /* Prevent other processes from resizing the shared memory */
      os2ShmSystemLock(pNode, _SHM_WRLCK_WAIT, OS2_SHM_DMS, 1);

      apRegion = sqlite3_realloc(
        pNode->apRegion, (iRegion + 1) * sizeof(apRegion[0]));

      if( apRegion ) {
        pNode->apRegion = apRegion;

        while( pNode->nRegion <= iRegion ) {
          sprintf(shmName, "%s-%u", 
                  pNode->shmBaseName, pNode->nRegion);

          if( DosGetNamedSharedMem(&pvTemp, (PSZ)shmName, 
                PAG_READ | PAG_WRITE) != NO_ERROR ) {
            if( !bExtend )
              break;

            if( DosAllocSharedMem(&pvTemp, (PSZ)shmName, szRegion,
                  PAG_READ | PAG_WRITE | PAG_COMMIT | OBJ_ANY) != NO_ERROR && 
                DosAllocSharedMem(&pvTemp, (PSZ)shmName, szRegion,
                  PAG_READ | PAG_WRITE | PAG_COMMIT) != NO_ERROR ) { 
              rc = SQLITE_NOMEM;
              break;
            }
          }

          apRegion[pNode->nRegion++] = pvTemp;
        }

        /* zero out remaining entries */ 
        for( n = pNode->nRegion; n <= iRegion; n++ )
          pNode->apRegion[n] = NULL;

        /* Return this region (maybe zero) */
        *pp = pNode->apRegion[iRegion];
      } else {
        rc = SQLITE_NOMEM;
      }

      /* Allow other processes to resize the shared memory */
      os2ShmSystemLock(pNode, _SHM_UNLCK, OS2_SHM_DMS, 1);
      
    } else {
      /* Region has been mapped previously */
      *pp = pNode->apRegion[iRegion];
    }

    sqlite3_mutex_leave(pNode->mutex);
  } 

  ERR_TRACE(rc, ("os2ShmMap: %s iRgn = %d, szRgn = %d, bExt = %d : %d\n", 
                 pFile->zFullPathCp, iRegion, szRegion, bExtend, rc))
          
  return rc;
}

/*
** Close a connection to shared-memory.  Delete the underlying
** storage if deleteFlag is true.
**
** If there is no shared memory associated with the connection then this
** routine is a harmless no-op.
*/
static int os2ShmUnmap(
  sqlite3_file *id,               /* The underlying database file */
  int deleteFlag                  /* Delete shared-memory if true */
){
  os2File *pFile = (os2File*)id;
  os2ShmLink *pLink = pFile->pShmLink;
  
  if( pLink ) {
    int nRef = -1;
    os2ShmLink **ppLink;
    os2ShmNode *pNode = pLink->pShmNode;

    sqlite3_mutex_enter(pNode->mutex);
    
    for( ppLink = &pNode->pFirst;
         *ppLink && *ppLink != pLink;
         ppLink = &(*ppLink)->pNext )   ;
         
    assert(*ppLink);

    if( *ppLink ) {
      *ppLink = pLink->pNext;
      nRef = --pNode->nRef;
    } else {
      ERR_TRACE(1, ("os2ShmUnmap: link not found ! %s\n", 
                    pNode->shmBaseName))
    }
    
    pFile->pShmLink = NULL;
    sqlite3_free(pLink);

    sqlite3_mutex_leave(pNode->mutex);
    
    if( nRef == 0 )
      os2PurgeShmNodes( deleteFlag );
  }

  return SQLITE_OK;
}

/*
** Change the lock state for a shared-memory segment.
**
** Note that the relationship between SHAREd and EXCLUSIVE locks is a little
** different here than in posix.  In xShmLock(), one can go from unlocked
** to shared and back or from unlocked to exclusive and back.  But one may
** not go from shared to exclusive or from exclusive to shared.
*/
static int os2ShmLock(
  sqlite3_file *id,          /* Database file holding the shared memory */
  int ofst,                  /* First lock to acquire or release */
  int n,                     /* Number of locks to acquire or release */
  int flags                  /* What to do with the lock */
){
  u32 mask;                             /* Mask of locks to take or release */
  int rc = SQLITE_OK;                   /* Result code */
  os2File *pFile = (os2File*)id;
  os2ShmLink *p = pFile->pShmLink;      /* The shared memory being locked */
  os2ShmLink *pX;                       /* For looping over all siblings */
  os2ShmNode *pShmNode = p->pShmNode;   /* Our node */
  
  assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
  assert( n>=1 );
  assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
       || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
       || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
  assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );

  mask = (u32)((1U<<(ofst+n)) - (1U<<ofst));
  assert( n>1 || mask==(1<<ofst) );


  sqlite3_mutex_enter(pShmNode->mutex);

  if( flags & SQLITE_SHM_UNLOCK ){
    u32 allMask = 0; /* Mask of locks held by siblings */

    /* See if any siblings hold this same lock */
    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
      if( pX==p ) continue;
      assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
      allMask |= pX->sharedMask;
    }

    /* Unlock the system-level locks */
    if( (mask & allMask)==0 ){
      rc = os2ShmSystemLock(pShmNode, _SHM_UNLCK, ofst+OS2_SHM_BASE, n);
    }else{
      rc = SQLITE_OK;
    }

    /* Undo the local locks */
    if( rc==SQLITE_OK ){
      p->exclMask &= ~mask;
      p->sharedMask &= ~mask;
    } 
  }else if( flags & SQLITE_SHM_SHARED ){
    u32 allShared = 0;  /* Union of locks held by connections other than "p" */

    /* Find out which shared locks are already held by sibling connections.
    ** If any sibling already holds an exclusive lock, go ahead and return
    ** SQLITE_BUSY.
    */
    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
      if( (pX->exclMask & mask)!=0 ){
        rc = SQLITE_BUSY;
        break;
      }
      allShared |= pX->sharedMask;
    }

    /* Get shared locks at the system level, if necessary */
    if( rc==SQLITE_OK ){
      if( (allShared & mask)==0 ){
        rc = os2ShmSystemLock(pShmNode, _SHM_RDLCK, ofst+OS2_SHM_BASE, n);
      }else{
        rc = SQLITE_OK;
      }
    }

    /* Get the local shared locks */
    if( rc==SQLITE_OK ){
      p->sharedMask |= mask;
    }
  }else{
    /* Make sure no sibling connections hold locks that will block this
    ** lock.  If any do, return SQLITE_BUSY right away.
    */
    for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
      if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
        rc = SQLITE_BUSY;
        break;
      }
    }
  
    /* Get the exclusive locks at the system level.  Then if successful
    ** also mark the local connection as being locked.
    */
    if( rc==SQLITE_OK ){
      rc = os2ShmSystemLock(pShmNode, _SHM_WRLCK, ofst+OS2_SHM_BASE, n);
      if( rc==SQLITE_OK ){
        assert( (p->sharedMask & mask)==0 );
        p->exclMask |= mask;
      }
    }
  }

  sqlite3_mutex_leave(pShmNode->mutex);
  
  OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x %s\n",
           p->id, (int)GetCurrentProcessId(), p->sharedMask, p->exclMask,
           rc ? "failed" : "ok"));

  ERR_TRACE(rc, ("os2ShmLock: ofst = %d, n = %d, flags = 0x%x -> %d \n", 
                 ofst, n, flags, rc))
                  
  return rc; 
}

/*
** Implement a memory barrier or memory fence on shared memory.
**
** All loads and stores begun before the barrier must complete before
** any load or store begun after the barrier.
*/
static void os2ShmBarrier(
  sqlite3_file *id                /* Database file holding the shared memory */
){
  UNUSED_PARAMETER(id);
  os2ShmEnterMutex();
  os2ShmLeaveMutex();
}

#else
# define os2ShmMap     0
# define os2ShmLock    0
# define os2ShmBarrier 0
# define os2ShmUnmap   0
#endif /* #ifndef SQLITE_OMIT_WAL */


/*
** This vector defines all the methods that can operate on an
** sqlite3_file for os2.
*/
static const sqlite3_io_methods os2IoMethod = {
  2,                              /* iVersion */
  os2Close,                       /* xClose */
  os2Read,                        /* xRead */
  os2Write,                       /* xWrite */
  os2Truncate,                    /* xTruncate */
  os2Sync,                        /* xSync */
  os2FileSize,                    /* xFileSize */
  os2Lock,                        /* xLock */
  os2Unlock,                      /* xUnlock */
  os2CheckReservedLock,           /* xCheckReservedLock */
  os2FileControl,                 /* xFileControl */
  os2SectorSize,                  /* xSectorSize */
  os2DeviceCharacteristics,       /* xDeviceCharacteristics */
  os2ShmMap,                      /* xShmMap */
  os2ShmLock,                     /* xShmLock */
  os2ShmBarrier,                  /* xShmBarrier */
  os2ShmUnmap                     /* xShmUnmap */
};


/***************************************************************************
** Here ends the I/O methods that form the sqlite3_io_methods object.
**
** The next block of code implements the VFS methods.
****************************************************************************/

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at pVfs->mxPathname characters.
*/
static int getTempname(int nBuf, char *zBuf ){
  static const char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  PSZ zTempPathCp;      
  char zTempPath[CCHMAXPATH];
  ULONG ulDriveNum, ulDriveMap;
  
  /* It's odd to simulate an io-error here, but really this is just
  ** using the io-error infrastructure to test that SQLite handles this
  ** function failing. 
  */
  SimulateIOError( return SQLITE_IOERR );

  if( sqlite3_temp_directory ) {
    sqlite3_snprintf(CCHMAXPATH-30, zTempPath, "%s", sqlite3_temp_directory);
  } else if( DosScanEnv( (PSZ)"TEMP",   &zTempPathCp ) == NO_ERROR ||
             DosScanEnv( (PSZ)"TMP",    &zTempPathCp ) == NO_ERROR ||
             DosScanEnv( (PSZ)"TMPDIR", &zTempPathCp ) == NO_ERROR ) {
    char *zTempPathUTF = convertCpPathToUtf8( (char *)zTempPathCp );
    sqlite3_snprintf(CCHMAXPATH-30, zTempPath, "%s", zTempPathUTF);
    free( zTempPathUTF );
  } else if( DosQueryCurrentDisk( &ulDriveNum, &ulDriveMap ) == NO_ERROR ) {
    zTempPath[0] = (char)('A' + ulDriveNum - 1);
    zTempPath[1] = ':'; 
    zTempPath[2] = '\0'; 
  } else {
    zTempPath[0] = '\0'; 
  }
  
  /* Strip off a trailing slashes or backslashes, otherwise we would get *
   * multiple (back)slashes which causes DosOpen() to fail.              *
   * Trailing spaces are not allowed, either.                            */
  j = sqlite3Strlen30(zTempPath);
  while( j > 0 && ( zTempPath[j-1] == '\\' || zTempPath[j-1] == '/' || 
                    zTempPath[j-1] == ' ' ) ){
    j--;
  }
  zTempPath[j] = '\0';
  
  /* We use 20 bytes to randomize the name */
  sqlite3_snprintf(nBuf-22, zBuf,
                   "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath);
  j = sqlite3Strlen30(zBuf);
  sqlite3_randomness( 20, &zBuf[j] );
  for( i = 0; i < 20; i++, j++ ){
    zBuf[j] = zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
  }
  zBuf[j] = 0;

  OSTRACE(( "TEMP FILENAME: %s\n", zBuf ));
  return SQLITE_OK;
}


/*
** Turn a relative pathname into a full pathname.  Write the full
** pathname into zFull[].  zFull[] will be at least pVfs->mxPathname
** bytes in size.
*/
static int os2FullPathname(
  sqlite3_vfs *pVfs,          /* Pointer to vfs object */
  const char *zRelative,      /* Possibly relative input path */
  int nFull,                  /* Size of output buffer in bytes */
  char *zFull                 /* Output buffer */
){
  char *zRelativeCp = convertUtf8PathToCp( zRelative );
  char zFullCp[CCHMAXPATH] = "\0";
  char *zFullUTF;
  APIRET rc = DosQueryPathInfo( (PSZ)zRelativeCp, FIL_QUERYFULLNAME, 
                                zFullCp, CCHMAXPATH );
  free( zRelativeCp );
  zFullUTF = convertCpPathToUtf8( zFullCp );
  sqlite3_snprintf( nFull, zFull, zFullUTF );
  free( zFullUTF );
  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
}


/*
** Open a file.
*/
static int os2Open(
  sqlite3_vfs *pVfs,            /* Not used */
  const char *zName,            /* Name of the file (UTF-8) */
  sqlite3_file *id,             /* Write the SQLite file handle here */
  int flags,                    /* Open mode flags */
  int *pOutFlags                /* Status return flags */
){
  HFILE h;
  ULONG ulOpenFlags = 0;
  ULONG ulOpenMode = 0;
  ULONG ulAction = 0;
  ULONG rc;
  os2File *pFile = (os2File*)id;
  const char *zUtf8Name = zName;
  char *zNameCp;
  char  zTmpname[CCHMAXPATH];

  int isExclusive  = (flags & SQLITE_OPEN_EXCLUSIVE);
  int isCreate     = (flags & SQLITE_OPEN_CREATE);
  int isReadWrite  = (flags & SQLITE_OPEN_READWRITE);
#ifndef NDEBUG
  int isDelete     = (flags & SQLITE_OPEN_DELETEONCLOSE);
  int isReadonly   = (flags & SQLITE_OPEN_READONLY);
  int eType        = (flags & 0xFFFFFF00);
  int isOpenJournal = (isCreate && (
        eType==SQLITE_OPEN_MASTER_JOURNAL 
     || eType==SQLITE_OPEN_MAIN_JOURNAL 
     || eType==SQLITE_OPEN_WAL
  ));
#endif

  UNUSED_PARAMETER(pVfs);
  assert( id!=0 );

  /* Check the following statements are true: 
  **
  **   (a) Exactly one of the READWRITE and READONLY flags must be set, and 
  **   (b) if CREATE is set, then READWRITE must also be set, and
  **   (c) if EXCLUSIVE is set, then CREATE must also be set.
  **   (d) if DELETEONCLOSE is set, then CREATE must also be set.
  */
  assert((isReadonly==0 || isReadWrite==0) && (isReadWrite || isReadonly));
  assert(isCreate==0 || isReadWrite);
  assert(isExclusive==0 || isCreate);
  assert(isDelete==0 || isCreate);

  /* The main DB, main journal, WAL file and master journal are never 
  ** automatically deleted. Nor are they ever temporary files.  */
  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_DB );
  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MAIN_JOURNAL );
  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_MASTER_JOURNAL );
  assert( (!isDelete && zName) || eType!=SQLITE_OPEN_WAL );

  /* Assert that the upper layer has set one of the "file-type" flags. */
  assert( eType==SQLITE_OPEN_MAIN_DB      || eType==SQLITE_OPEN_TEMP_DB 
       || eType==SQLITE_OPEN_MAIN_JOURNAL || eType==SQLITE_OPEN_TEMP_JOURNAL 
       || eType==SQLITE_OPEN_SUBJOURNAL   || eType==SQLITE_OPEN_MASTER_JOURNAL 
       || eType==SQLITE_OPEN_TRANSIENT_DB || eType==SQLITE_OPEN_WAL
  );

  memset( pFile, 0, sizeof(*pFile) );
  pFile->h = (HFILE)-1;

  /* If the second argument to this function is NULL, generate a 
  ** temporary file name to use 
  */
  if( !zUtf8Name ){
    assert(isDelete && !isOpenJournal);
    rc = getTempname(CCHMAXPATH, zTmpname);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    zUtf8Name = zTmpname;
  }

  if( isReadWrite ){
    ulOpenMode |= OPEN_ACCESS_READWRITE;
  }else{
    ulOpenMode |= OPEN_ACCESS_READONLY;
  }

  /* Open in random access mode for possibly better speed.  Allow full
  ** sharing because file locks will provide exclusive access when needed.
  ** The handle should not be inherited by child processes and we don't 
  ** want popups from the critical error handler.
  */
  ulOpenMode |= OPEN_FLAGS_RANDOM | OPEN_SHARE_DENYNONE | 
                OPEN_FLAGS_NOINHERIT | OPEN_FLAGS_FAIL_ON_ERROR;

  /* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is 
  ** created. SQLite doesn't use it to indicate "exclusive access" 
  ** as it is usually understood.
  */
  if( isExclusive ){
    /* Creates a new file, only if it does not already exist. */
    /* If the file exists, it fails. */
    ulOpenFlags |= OPEN_ACTION_CREATE_IF_NEW | OPEN_ACTION_FAIL_IF_EXISTS;
  }else if( isCreate ){
    /* Open existing file, or create if it doesn't exist */
    ulOpenFlags |= OPEN_ACTION_CREATE_IF_NEW | OPEN_ACTION_OPEN_IF_EXISTS;
  }else{
    /* Opens a file, only if it exists. */
    ulOpenFlags |= OPEN_ACTION_FAIL_IF_NEW | OPEN_ACTION_OPEN_IF_EXISTS;
  }

  zNameCp = convertUtf8PathToCp( zUtf8Name );
  rc = DosOpen( (PSZ)zNameCp,
                &h,
                &ulAction,
                0L,
                FILE_NORMAL,
                ulOpenFlags,
                ulOpenMode,
                (PEAOP2)NULL );
  free( zNameCp );

  if( rc != NO_ERROR ){
    OSTRACE(( "OPEN Invalid handle rc=%d: zName=%s, ulAction=%#lx, ulFlags=%#lx, ulMode=%#lx\n",
              rc, zUtf8Name, ulAction, ulOpenFlags, ulOpenMode ));

    if( isReadWrite ){
      return os2Open( pVfs, zName, id,
                      ((flags|SQLITE_OPEN_READONLY)&~(SQLITE_OPEN_CREATE|SQLITE_OPEN_READWRITE)),
                      pOutFlags );
    }else{
      return SQLITE_CANTOPEN;
    }
  }

  if( pOutFlags ){
    *pOutFlags = isReadWrite ? SQLITE_OPEN_READWRITE : SQLITE_OPEN_READONLY;
  }

  os2FullPathname( pVfs, zUtf8Name, sizeof( zTmpname ), zTmpname );
  pFile->zFullPathCp = convertUtf8PathToCp( zTmpname );
  pFile->pMethod = &os2IoMethod;
  pFile->flags = flags;
  pFile->h = h;

  OpenCounter(+1);
  OSTRACE(( "OPEN %d pOutFlags=%d\n", pFile->h, pOutFlags ));
  return SQLITE_OK;
}

/*
** Delete the named file.
*/
static int os2Delete(
  sqlite3_vfs *pVfs,                     /* Not used on os2 */
  const char *zFilename,                 /* Name of file to delete */
  int syncDir                            /* Not used on os2 */
){
  APIRET rc;
  char *zFilenameCp;
  SimulateIOError( return SQLITE_IOERR_DELETE );
  zFilenameCp = convertUtf8PathToCp( zFilename );
  rc = DosDelete( (PSZ)zFilenameCp );
  free( zFilenameCp );
  OSTRACE(( "DELETE \"%s\"\n", zFilename ));
  return (rc == NO_ERROR ||
          rc == ERROR_FILE_NOT_FOUND ||
          rc == ERROR_PATH_NOT_FOUND ) ? SQLITE_OK : SQLITE_IOERR_DELETE;
}

/*
** Check the existance and status of a file.
*/
static int os2Access(
  sqlite3_vfs *pVfs,        /* Not used on os2 */
  const char *zFilename,    /* Name of file to check */
  int flags,                /* Type of test to make on this file */
  int *pOut                 /* Write results here */
){
  APIRET rc;
  FILESTATUS3 fsts3ConfigInfo;
  char *zFilenameCp;

  UNUSED_PARAMETER(pVfs);
  SimulateIOError( return SQLITE_IOERR_ACCESS; );
  
  zFilenameCp = convertUtf8PathToCp( zFilename );
  rc = DosQueryPathInfo( (PSZ)zFilenameCp, FIL_STANDARD,
                         &fsts3ConfigInfo, sizeof(FILESTATUS3) );
  free( zFilenameCp );
  OSTRACE(( "ACCESS fsts3ConfigInfo.attrFile=%d flags=%d rc=%d\n",
            fsts3ConfigInfo.attrFile, flags, rc ));

  switch( flags ){
    case SQLITE_ACCESS_EXISTS:
      /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
      ** as if it does not exist.
      */
      if( fsts3ConfigInfo.cbFile == 0 ) 
        rc = ERROR_FILE_NOT_FOUND;
      break;
    case SQLITE_ACCESS_READ:
      break;
    case SQLITE_ACCESS_READWRITE:
      if( fsts3ConfigInfo.attrFile & FILE_READONLY )
        rc = ERROR_ACCESS_DENIED;
      break;
    default:
      rc = ERROR_FILE_NOT_FOUND;
      assert( !"Invalid flags argument" );
  }

  *pOut = (rc == NO_ERROR);
  OSTRACE(( "ACCESS %s flags %d: rc=%d\n", zFilename, flags, *pOut ));

  return SQLITE_OK;
}


#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
static void *os2DlOpen(sqlite3_vfs *pVfs, const char *zFilename){
  HMODULE hmod;
  APIRET rc;
  char *zFilenameCp = convertUtf8PathToCp(zFilename);
  rc = DosLoadModule(NULL, 0, (PSZ)zFilenameCp, &hmod);
  free(zFilenameCp);
  return rc != NO_ERROR ? 0 : (void*)hmod;
}
/*
** A no-op since the error code is returned on the DosLoadModule call.
** os2Dlopen returns zero if DosLoadModule is not successful.
*/
static void os2DlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
/* no-op */
}
static void (*os2DlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol))(void){
  PFN pfn;
  APIRET rc;
  rc = DosQueryProcAddr((HMODULE)pHandle, 0L, (PSZ)zSymbol, &pfn);
  if( rc != NO_ERROR ){
    /* if the symbol itself was not found, search again for the same
     * symbol with an extra underscore, that might be needed depending
     * on the calling convention */
    char _zSymbol[256] = "_";
    strncat(_zSymbol, zSymbol, 254);
    rc = DosQueryProcAddr((HMODULE)pHandle, 0L, (PSZ)_zSymbol, &pfn);
  }
  return rc != NO_ERROR ? 0 : (void(*)(void))pfn;
}
static void os2DlClose(sqlite3_vfs *pVfs, void *pHandle){
  DosFreeModule((HMODULE)pHandle);
}
#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
  #define os2DlOpen 0
  #define os2DlError 0
  #define os2DlSym 0
  #define os2DlClose 0
#endif


/*
** Write up to nBuf bytes of randomness into zBuf.
*/
static int os2Randomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf ){
  int n = 0;
#if defined(SQLITE_TEST)
  n = nBuf;
  memset(zBuf, 0, nBuf);
#else
  int i;                           
  PPIB ppib;
  PTIB ptib;
  DATETIME dt; 
  static unsigned c = 0;
  /* Ordered by variation probability */
  static ULONG svIdx[6] = { QSV_MS_COUNT, QSV_TIME_LOW,
                            QSV_MAXPRMEM, QSV_MAXSHMEM,
                            QSV_TOTAVAILMEM, QSV_TOTRESMEM };

  /* 8 bytes; timezone and weekday don't increase the randomness much */
  if( (int)sizeof(dt)-3 <= nBuf - n ){
    c += 0x0100;
    DosGetDateTime(&dt);
    dt.year = (USHORT)((dt.year - 1900) | c);
    memcpy(&zBuf[n], &dt, sizeof(dt)-3);
    n += sizeof(dt)-3;
  }

  /* 4 bytes; PIDs and TIDs are 16 bit internally, so combine them */
  if( (int)sizeof(ULONG) <= nBuf - n ){
    DosGetInfoBlocks(&ptib, &ppib);
    *(PULONG)&zBuf[n] = MAKELONG(ppib->pib_ulpid,
                                 ptib->tib_ptib2->tib2_ultid);
    n += sizeof(ULONG);
  }

  /* Up to 6 * 4 bytes; variables depend on the system state */
  for( i = 0; i < 6 && (int)sizeof(ULONG) <= nBuf - n; i++ ){
    DosQuerySysInfo(svIdx[i], svIdx[i], 
                    (PULONG)&zBuf[n], sizeof(ULONG));
    n += sizeof(ULONG);
  } 
#endif

  return n;
}

/*
** Sleep for a little while.  Return the amount of time slept.
** The argument is the number of microseconds we want to sleep.
** The return value is the number of microseconds of sleep actually
** requested from the underlying operating system, a number which
** might be greater than or equal to the argument, but not less
** than the argument.
*/
static int os2Sleep( sqlite3_vfs *pVfs, int microsec ){
  DosSleep( (microsec/1000) );
  return microsec;
}

/*
** The following variable, if set to a non-zero value, becomes the result
** returned from sqlite3OsCurrentTime().  This is used for testing.
*/
#ifdef SQLITE_TEST
int sqlite3_current_time = 0;
#endif

/*
** Find the current time (in Universal Coordinated Time).  Write into *piNow
** the current time and date as a Julian Day number times 86_400_000.  In
** other words, write into *piNow the number of milliseconds since the Julian
** epoch of noon in Greenwich on November 24, 4714 B.C according to the
** proleptic Gregorian calendar.
**
** On success, return 0.  Return 1 if the time and date cannot be found.
*/
static int os2CurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
#ifdef SQLITE_TEST
  static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
#endif
  int year, month, datepart, timepart;
 
  DATETIME dt;
  DosGetDateTime( &dt );

  year = dt.year;
  month = dt.month;

  /* Calculations from http://www.astro.keele.ac.uk/~rno/Astronomy/hjd.html
  ** http://www.astro.keele.ac.uk/~rno/Astronomy/hjd-0.1.c
  ** Calculate the Julian days
  */
  datepart = (int)dt.day - 32076 +
    1461*(year + 4800 + (month - 14)/12)/4 +
    367*(month - 2 - (month - 14)/12*12)/12 -
    3*((year + 4900 + (month - 14)/12)/100)/4;

  /* Time in milliseconds, hours to noon added */
  timepart = 12*3600*1000 + dt.hundredths*10 + dt.seconds*1000 +
    ((int)dt.minutes + dt.timezone)*60*1000 + dt.hours*3600*1000;

  *piNow = (sqlite3_int64)datepart*86400*1000 + timepart;
   
#ifdef SQLITE_TEST
  if( sqlite3_current_time ){
    *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
  }
#endif

  UNUSED_PARAMETER(pVfs);
  return 0;
}

/*
** Find the current time (in Universal Coordinated Time).  Write the
** current time and date as a Julian Day number into *prNow and
** return 0.  Return 1 if the time and date cannot be found.
*/
static int os2CurrentTime( sqlite3_vfs *pVfs, double *prNow ){
  int rc;
  sqlite3_int64 i;
  rc = os2CurrentTimeInt64(pVfs, &i);
  if( !rc ){
    *prNow = i/86400000.0;
  }
  return rc;
}

/*
** The idea is that this function works like a combination of
** GetLastError() and FormatMessage() on windows (or errno and
** strerror_r() on unix). After an error is returned by an OS
** function, SQLite calls this function with zBuf pointing to
** a buffer of nBuf bytes. The OS layer should populate the
** buffer with a nul-terminated UTF-8 encoded error message
** describing the last IO error to have occurred within the calling
** thread.
**
** If the error message is too large for the supplied buffer,
** it should be truncated. The return value of xGetLastError
** is zero if the error message fits in the buffer, or non-zero
** otherwise (if the message was truncated). If non-zero is returned,
** then it is not necessary to include the nul-terminator character
** in the output buffer.
**
** Not supplying an error message will have no adverse effect
** on SQLite. It is fine to have an implementation that never
** returns an error message:
**
**   int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
**     assert(zBuf[0]=='\0');
**     return 0;
**   }
**
** However if an error message is supplied, it will be incorporated
** by sqlite into the error message available to the user using
** sqlite3_errmsg(), possibly making IO errors easier to debug.
*/
static int os2GetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
  assert(zBuf[0]=='\0');
  return 0;
}

/*
** Initialize and deinitialize the operating system interface.
*/
int sqlite3_os_init(void){
  static sqlite3_vfs os2Vfs = {
    3,                 /* iVersion */
    sizeof(os2File),   /* szOsFile */
    CCHMAXPATH,        /* mxPathname */
    0,                 /* pNext */
    "os2",             /* zName */
    0,                 /* pAppData */

    os2Open,           /* xOpen */
    os2Delete,         /* xDelete */
    os2Access,         /* xAccess */
    os2FullPathname,   /* xFullPathname */
    os2DlOpen,         /* xDlOpen */
    os2DlError,        /* xDlError */
    os2DlSym,          /* xDlSym */
    os2DlClose,        /* xDlClose */
    os2Randomness,     /* xRandomness */
    os2Sleep,          /* xSleep */
    os2CurrentTime,    /* xCurrentTime */
    os2GetLastError,   /* xGetLastError */
    os2CurrentTimeInt64, /* xCurrentTimeInt64 */
    0,                 /* xSetSystemCall */
    0,                 /* xGetSystemCall */
    0                  /* xNextSystemCall */
  };
  sqlite3_vfs_register(&os2Vfs, 1);
  initUconvObjects();
/*  sqlite3OSTrace = 1; */
  return SQLITE_OK;
}
int sqlite3_os_end(void){
  freeUconvObjects();
  return SQLITE_OK;
}

#endif /* SQLITE_OS_OS2 */

    /* random NFS retry error, unless during file system support 
     * introspection, in which it actually means what it says */
    return SQLITE_BUSY;
    
  case EACCES: 
    /* EACCES is like EAGAIN during locking operations, but not any other time*/
    if( (sqliteIOErr == SQLITE_IOERR_LOCK) || 
	(sqliteIOErr == SQLITE_IOERR_UNLOCK) || 
	(sqliteIOErr == SQLITE_IOERR_RDLOCK) ||
	(sqliteIOErr == SQLITE_IOERR_CHECKRESERVEDLOCK) ){
      return SQLITE_BUSY;
    }
    /* else fall through */
  case EPERM: 
    return SQLITE_PERM;
    
  /* EDEADLK is only possible if a call to fcntl(F_SETLKW) is made. And

        tErrno = errno;
        rc = sqliteErrorFromPosixError(tErrno, SQLITE_IOERR_UNLOCK);
        if( IS_LOCK_ERROR(rc) ){
          storeLastErrno(pFile, tErrno);
        }
#else
        rc = SQLITE_IOERR_UNLOCK;
	    storeLastErrno(pFile, errno);
#endif
        pInode->eFileLock = NO_LOCK;
        pFile->eFileLock = NO_LOCK;
      }
    }

    /* Decrement the count of locks against this same file.  When the
    ** count reaches zero, close any other file descriptors whose close
    ** was deferred because of outstanding locks.
    */
    pInode->nLock--;
    assert( pInode->nLock>=0 );
    if( pInode->nLock==0 ){
      closePendingFds(pFile);
    }
  }
	
end_unlock:
  unixLeaveMutex();
  if( rc==SQLITE_OK ) pFile->eFileLock = eFileLock;
  return rc;
}

/*

static int dotlockUnlock(sqlite3_file *id, int eFileLock) {
  unixFile *pFile = (unixFile*)id;
  char *zLockFile = (char *)pFile->lockingContext;
  int rc;

  assert( pFile );
  OSTRACE(("UNLOCK  %d %d was %d pid=%d (dotlock)\n", pFile->h, eFileLock,
	   pFile->eFileLock, getpid()));
  assert( eFileLock<=SHARED_LOCK );
  
  /* no-op if possible */
  if( pFile->eFileLock==eFileLock ){
    return SQLITE_OK;
  }

static int semUnlock(sqlite3_file *id, int eFileLock) {
  unixFile *pFile = (unixFile*)id;
  sem_t *pSem = pFile->pInode->pSem;

  assert( pFile );
  assert( pSem );
  OSTRACE(("UNLOCK  %d %d was %d pid=%d (sem)\n", pFile->h, eFileLock,
	   pFile->eFileLock, getpid()));
  assert( eFileLock<=SHARED_LOCK );
  
  /* no-op if possible */
  if( pFile->eFileLock==eFileLock ){
    return SQLITE_OK;
  }
  

** as POSIX read & write locks over fixed set of locations (via fsctl),
** on AFP and SMB only exclusive byte-range locks are available via fsctl
** with _IOWR('z', 23, struct ByteRangeLockPB2) to track the same 5 states.
** To simulate a F_RDLCK on the shared range, on AFP a randomly selected
** address in the shared range is taken for a SHARED lock, the entire
** shared range is taken for an EXCLUSIVE lock):
**
**      PENDING_BYTE        0x40000000		   	
**      RESERVED_BYTE       0x40000001
**      SHARED_RANGE        0x40000002 -> 0x40000200
**
** This works well on the local file system, but shows a nearly 100x
** slowdown in read performance on AFP because the AFP client disables
** the read cache when byte-range locks are present.  Enabling the read
** cache exposes a cache coherency problem that is present on all OS X

# define FILE_FLAG_MASK          (0xFF3C0000)
#endif

#ifndef FILE_ATTRIBUTE_MASK
# define FILE_ATTRIBUTE_MASK     (0x0003FFF7)
#endif


/* Forward references */
typedef struct winShm winShm;           /* A connection to shared-memory */
typedef struct winShmNode winShmNode;   /* A region of shared-memory */


/*
** WinCE lacks native support for file locking so we have to fake it
** with some code of our own.
*/
#if SQLITE_OS_WINCE
typedef struct winceLock {

  const sqlite3_io_methods *pMethod; /*** Must be first ***/
  sqlite3_vfs *pVfs;      /* The VFS used to open this file */
  HANDLE h;               /* Handle for accessing the file */
  u8 locktype;            /* Type of lock currently held on this file */
  short sharedLockByte;   /* Randomly chosen byte used as a shared lock */
  u8 ctrlFlags;           /* Flags.  See WINFILE_* below */
  DWORD lastErrno;        /* The Windows errno from the last I/O error */

  winShm *pShm;           /* Instance of shared memory on this file */

  const char *zPath;      /* Full pathname of this file */
  int szChunk;            /* Chunk size configured by FCNTL_CHUNK_SIZE */
#if SQLITE_OS_WINCE
  LPWSTR zDeleteOnClose;  /* Name of file to delete when closing */
  HANDLE hMutex;          /* Mutex used to control access to shared lock */  
  HANDLE hShared;         /* Shared memory segment used for locking */
  winceLock local;        /* Locks obtained by this instance of winFile */

/*
 * The size of the buffer used by sqlite3_win32_write_debug().
 */
#ifndef SQLITE_WIN32_DBG_BUF_SIZE
#  define SQLITE_WIN32_DBG_BUF_SIZE   ((int)(4096-sizeof(DWORD)))
#endif

















/*
 * If compiled with SQLITE_WIN32_MALLOC on Windows, we will use the
 * various Win32 API heap functions instead of our own.
 */
#ifdef SQLITE_WIN32_MALLOC

/*

#else
  { "CreateFileW",             (SYSCALL)0,                       0 },
#endif

#define osCreateFileW ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD, \
        LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[5].pCurrent)

#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)

  { "CreateFileMappingW",      (SYSCALL)CreateFileMappingW,      0 },
#else
  { "CreateFileMappingW",      (SYSCALL)0,                       0 },
#endif

#define osCreateFileMappingW ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
        DWORD,DWORD,DWORD,LPCWSTR))aSyscall[6].pCurrent)

#endif

#ifndef osLockFileEx
#define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
        LPOVERLAPPED))aSyscall[45].pCurrent)
#endif

#if !SQLITE_OS_WINRT
  { "MapViewOfFile",           (SYSCALL)MapViewOfFile,           0 },
#else
  { "MapViewOfFile",           (SYSCALL)0,                       0 },
#endif

#define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        SIZE_T))aSyscall[46].pCurrent)

#else
  { "UnlockFileEx",            (SYSCALL)0,                       0 },
#endif

#define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        LPOVERLAPPED))aSyscall[55].pCurrent)


  { "UnmapViewOfFile",         (SYSCALL)UnmapViewOfFile,         0 },




#define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[56].pCurrent)

  { "WideCharToMultiByte",     (SYSCALL)WideCharToMultiByte,     0 },

#define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
        LPCSTR,LPBOOL))aSyscall[57].pCurrent)

#else
  { "WaitForSingleObject",     (SYSCALL)0,                       0 },
#endif

#define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
        DWORD))aSyscall[60].pCurrent)

#if !SQLITE_OS_WINCE
  { "WaitForSingleObjectEx",   (SYSCALL)WaitForSingleObjectEx,   0 },
#else
  { "WaitForSingleObjectEx",   (SYSCALL)0,                       0 },
#endif

#define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
        BOOL))aSyscall[61].pCurrent)

#if !SQLITE_OS_WINCE
  { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
#else
  { "SetFilePointerEx",        (SYSCALL)0,                       0 },
#endif

#define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
        PLARGE_INTEGER,DWORD))aSyscall[62].pCurrent)

#if SQLITE_OS_WINRT
  { "GetFileInformationByHandleEx", (SYSCALL)GetFileInformationByHandleEx, 0 },
#else
  { "GetFileInformationByHandleEx", (SYSCALL)0,                  0 },
#endif

#define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
        FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[63].pCurrent)

#if SQLITE_OS_WINRT
  { "MapViewOfFileFromApp",    (SYSCALL)MapViewOfFileFromApp,    0 },
#else
  { "MapViewOfFileFromApp",    (SYSCALL)0,                       0 },
#endif

#define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
        SIZE_T))aSyscall[64].pCurrent)

#define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[70].pCurrent)

  { "GetProcessHeap",          (SYSCALL)GetProcessHeap,          0 },

#define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[71].pCurrent)

#if SQLITE_OS_WINRT
  { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
#else
  { "CreateFileMappingFromApp", (SYSCALL)0,                      0 },
#endif

#define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
        LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[72].pCurrent)

    return 0;
  }
  zFilenameMbcs = unicodeToMbcs(zTmpWide);
  sqlite3_free(zTmpWide);
  return zFilenameMbcs;
}






































/*
** The return value of getLastErrorMsg
** is zero if the error message fits in the buffer, or non-zero
** otherwise (if the message was truncated).
*/
static int getLastErrorMsg(DWORD lastErrno, int nBuf, char *zBuf){

*/
#define MX_CLOSE_ATTEMPT 3
static int winClose(sqlite3_file *id){
  int rc, cnt = 0;
  winFile *pFile = (winFile*)id;

  assert( id!=0 );

  assert( pFile->pShm==0 );

  OSTRACE(("CLOSE %d\n", pFile->h));
  do{
    rc = osCloseHandle(pFile->h);
    /* SimulateIOError( rc=0; cnt=MX_CLOSE_ATTEMPT; ); */
  }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (sqlite3_win32_sleep(100), 1) );
#if SQLITE_OS_WINCE
#define WINCE_DELETION_ATTEMPTS 3

  }

  memset(pFile, 0, sizeof(*pFile));
  pFile->pMethod = &winIoMethod;
  pFile->h = h;
  pFile->lastErrno = NO_ERROR;
  pFile->pVfs = pVfs;

  pFile->pShm = 0;

  pFile->zPath = zName;
  if( sqlite3_uri_boolean(zName, "psow", SQLITE_POWERSAFE_OVERWRITE) ){
    pFile->ctrlFlags |= WINFILE_PSOW;
  }

#if SQLITE_OS_WINCE
  if( isReadWrite && eType==SQLITE_OPEN_MAIN_DB

  nNew = p->nHash*2;
  if( nNew<256 ){
    nNew = 256;
  }

  pcache1LeaveMutex(p->pGroup);
  if( p->nHash ){ sqlite3BeginBenignMalloc(); }
  apNew = (PgHdr1 **)sqlite3_malloc(sizeof(PgHdr1 *)*nNew);
  if( p->nHash ){ sqlite3EndBenignMalloc(); }
  pcache1EnterMutex(p->pGroup);
  if( apNew ){
    memset(apNew, 0, sizeof(PgHdr1 *)*nNew);
    for(i=0; i<p->nHash; i++){
      PgHdr1 *pPage;
      PgHdr1 *pNext = p->apHash[i];
      while( (pPage = pNext)!=0 ){
        unsigned int h = pPage->iKey % nNew;
        pNext = pPage->pNext;
        pPage->pNext = apNew[h];

  int separateCache = sqlite3GlobalConfig.bCoreMutex>0;
#endif

  assert( (szPage & (szPage-1))==0 && szPage>=512 && szPage<=65536 );
  assert( szExtra < 300 );

  sz = sizeof(PCache1) + sizeof(PGroup)*separateCache;
  pCache = (PCache1 *)sqlite3_malloc(sz);
  if( pCache ){
    memset(pCache, 0, sz);
    if( separateCache ){
      pGroup = (PGroup*)&pCache[1];
      pGroup->mxPinned = 10;
    }else{
      pGroup = &pcache1.grp;
    }
    pCache->pGroup = pGroup;

      { OP_AddImm,      1, 0,        0},    /* 0 */
      { OP_IfNeg,       1, 0,        0},    /* 1 */
      { OP_String8,     0, 3,        0},    /* 2 */
      { OP_ResultRow,   3, 1,        0},
    };

    int isQuick = (sqlite3Tolower(zLeft[0])=='q');














    /* Initialize the VDBE program */
    if( sqlite3ReadSchema(pParse) ) goto pragma_out;
    pParse->nMem = 6;
    sqlite3VdbeSetNumCols(v, 1);
    sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "integrity_check", SQLITE_STATIC);

    /* Do an integrity check on each database file */
    for(i=0; i<db->nDb; i++){
      HashElem *x;
      Hash *pTbls;
      int cnt = 0;

      if( OMIT_TEMPDB && i==1 ) continue;


      sqlite3CodeVerifySchema(pParse, i);
      addr = sqlite3VdbeAddOp1(v, OP_IfPos, 1); /* Halt if out of errors */
      sqlite3VdbeAddOp2(v, OP_Halt, 0, 0);
      sqlite3VdbeJumpHere(v, addr);

      /* Do an integrity check of the B-Tree
      **
      ** Begin by filling registers 2, 3, ... with the root pages numbers
      ** for all tables and indices in the database.
      */
      assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
      pTbls = &db->aDb[i].pSchema->tblHash;
      for(x=sqliteHashFirst(pTbls); x; x=sqliteHashNext(x)){
        Table *pTab = sqliteHashData(x);
        Index *pIdx;
        sqlite3VdbeAddOp2(v, OP_Integer, pTab->tnum, 2+cnt);
        cnt++;
        for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){

** The counter *cnt is incremented each time.  After counter exceeds
** 16 (the number of significant digits in a 64-bit float) '0' is
** always returned.
*/
static char et_getdigit(LONGDOUBLE_TYPE *val, int *cnt){
  int digit;
  LONGDOUBLE_TYPE d;
  if( (*cnt)++ >= 16 ) return '0';

  digit = (int)*val;
  d = digit;
  digit += '0';
  *val = (*val - d)*10.0;
  return (char)digit;
}
#endif /* SQLITE_OMIT_FLOATING_POINT */

        exp = 0;
        if( sqlite3IsNaN((double)realvalue) ){
          bufpt = "NaN";
          length = 3;
          break;
        }
        if( realvalue>0.0 ){

          while( realvalue>=1e32 && exp<=350 ){ realvalue *= 1e-32; exp+=32; }

          while( realvalue>=1e8 && exp<=350 ){ realvalue *= 1e-8; exp+=8; }
          while( realvalue>=10.0 && exp<=350 ){ realvalue *= 0.1; exp++; }

          while( realvalue<1e-8 ){ realvalue *= 1e8; exp-=8; }
          while( realvalue<1.0 ){ realvalue *= 10.0; exp--; }
          if( exp>350 ){
            if( prefix=='-' ){
              bufpt = "-Inf";
            }else if( prefix=='+' ){
              bufpt = "+Inf";

          if( exp<-4 || exp>precision ){
            xtype = etEXP;
          }else{
            precision = precision - exp;
            xtype = etFLOAT;
          }
        }else{
          flag_rtz = 0;
        }
        if( xtype==etEXP ){
          e2 = 0;
        }else{
          e2 = exp;
        }
        if( e2+precision+width > etBUFSIZE - 15 ){
          bufpt = zExtra = sqlite3Malloc( e2+precision+width+15 );
          if( bufpt==0 ){
            pAccum->mallocFailed = 1;
            return;
          }
        }
        zOut = bufpt;
        nsd = 0;
        flag_dp = (precision>0 ?1:0) | flag_alternateform | flag_altform2;
        /* The sign in front of the number */
        if( prefix ){
          *(bufpt++) = prefix;
        }
        /* Digits prior to the decimal point */
        if( e2<0 ){

** This file contains routines used for walking the parser tree and
** resolve all identifiers by associating them with a particular
** table and column.
*/
#include "sqliteInt.h"
#include <stdlib.h>
#include <string.h>
























/*
** Turn the pExpr expression into an alias for the iCol-th column of the
** result set in pEList.
**
** If the result set column is a simple column reference, then this routine
** makes an exact copy.  But for any other kind of expression, this

** Is equivalent to:
**
**     SELECT random()%5 AS x, count(*) FROM tab GROUP BY random()%5
**
** The result of random()%5 in the GROUP BY clause is probably different
** from the result in the result-set.  We might fix this someday.  Or
** then again, we might not...






*/
static void resolveAlias(
  Parse *pParse,         /* Parsing context */
  ExprList *pEList,      /* A result set */
  int iCol,              /* A column in the result set.  0..pEList->nExpr-1 */
  Expr *pExpr,           /* Transform this into an alias to the result set */
  const char *zType      /* "GROUP" or "ORDER" or "" */

){
  Expr *pOrig;           /* The iCol-th column of the result set */
  Expr *pDup;            /* Copy of pOrig */
  sqlite3 *db;           /* The database connection */

  assert( iCol>=0 && iCol<pEList->nExpr );
  pOrig = pEList->a[iCol].pExpr;
  assert( pOrig!=0 );
  assert( pOrig->flags & EP_Resolved );
  db = pParse->db;
  if( pOrig->op!=TK_COLUMN && zType[0]!='G' ){
    pDup = sqlite3ExprDup(db, pOrig, 0);

    pDup = sqlite3PExpr(pParse, TK_AS, pDup, 0, 0);
    if( pDup==0 ) return;
    if( pEList->a[iCol].iAlias==0 ){
      pEList->a[iCol].iAlias = (u16)(++pParse->nAlias);
    }
    pDup->iTable = pEList->a[iCol].iAlias;
  }else if( ExprHasProperty(pOrig, EP_IntValue) || pOrig->u.zToken==0 ){

  Parse *pParse,       /* The parsing context */
  const char *zDb,     /* Name of the database containing table, or NULL */
  const char *zTab,    /* Name of table containing column, or NULL */
  const char *zCol,    /* Name of the column. */
  NameContext *pNC,    /* The name context used to resolve the name */
  Expr *pExpr          /* Make this EXPR node point to the selected column */
){
  int i, j;            /* Loop counters */
  int cnt = 0;                      /* Number of matching column names */
  int cntTab = 0;                   /* Number of matching table names */

  sqlite3 *db = pParse->db;         /* The database connection */
  struct SrcList_item *pItem;       /* Use for looping over pSrcList items */
  struct SrcList_item *pMatch = 0;  /* The matching pSrcList item */
  NameContext *pTopNC = pNC;        /* First namecontext in the list */
  Schema *pSchema = 0;              /* Schema of the expression */
  int isTrigger = 0;

          assert( pExpr->x.pList==0 );
          assert( pExpr->x.pSelect==0 );
          pOrig = pEList->a[j].pExpr;
          if( (pNC->ncFlags&NC_AllowAgg)==0 && ExprHasProperty(pOrig, EP_Agg) ){
            sqlite3ErrorMsg(pParse, "misuse of aliased aggregate %s", zAs);
            return WRC_Abort;
          }
          resolveAlias(pParse, pEList, j, pExpr, "");
          cnt = 1;
          pMatch = 0;
          assert( zTab==0 && zDb==0 );
          goto lookupname_end;
        }
      } 
    }

    /* Advance to the next name context.  The loop will exit when either
    ** we have a match (cnt>0) or when we run out of name contexts.
    */
    if( cnt==0 ){
      pNC = pNC->pNext;

    }
  }

  /*
  ** If X and Y are NULL (in other words if only the column name Z is
  ** supplied) and the value of Z is enclosed in double-quotes, then
  ** Z is a string literal if it doesn't match any column names.  In that

        sqlite3ErrorMsg(pParse, "no such function: %.*s", nId, zId);
        pNC->nErr++;
      }else if( wrong_num_args ){
        sqlite3ErrorMsg(pParse,"wrong number of arguments to function %.*s()",
             nId, zId);
        pNC->nErr++;
      }


      if( is_agg ){

        pExpr->op = TK_AGG_FUNCTION;



        pNC->ncFlags |= NC_HasAgg;
      }
      if( is_agg ) pNC->ncFlags &= ~NC_AllowAgg;
      sqlite3WalkExprList(pWalker, pList);
      if( is_agg ) pNC->ncFlags |= NC_AllowAgg;

      /* FIX ME:  Compute pExpr->affinity based on the expected return
      ** type of the function 
      */
      return WRC_Prune;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case TK_SELECT:

  assert( pEList!=0 );  /* sqlite3SelectNew() guarantees this */
  for(i=0, pItem=pOrderBy->a; i<pOrderBy->nExpr; i++, pItem++){
    if( pItem->iOrderByCol ){
      if( pItem->iOrderByCol>pEList->nExpr ){
        resolveOutOfRangeError(pParse, zType, i+1, pEList->nExpr);
        return 1;
      }
      resolveAlias(pParse, pEList, pItem->iOrderByCol-1, pItem->pExpr, zType);
    }
  }
  return 0;
}

/*
** pOrderBy is an ORDER BY or GROUP BY clause in SELECT statement pSelect.

}

/*
** Initialize a SelectDest structure.
*/
void sqlite3SelectDestInit(SelectDest *pDest, int eDest, int iParm){
  pDest->eDest = (u8)eDest;
  pDest->iParm = iParm;
  pDest->affinity = 0;
  pDest->iMem = 0;
  pDest->nMem = 0;
}


/*
** Allocate a new Select structure and return a pointer to that
** structure.
*/

  int iBreak              /* Jump here to break out of the inner loop */
){
  Vdbe *v = pParse->pVdbe;
  int i;
  int hasDistinct;        /* True if the DISTINCT keyword is present */
  int regResult;              /* Start of memory holding result set */
  int eDest = pDest->eDest;   /* How to dispose of results */
  int iParm = pDest->iParm;   /* First argument to disposal method */
  int nResultCol;             /* Number of result columns */

  assert( v );
  if( NEVER(v==0) ) return;
  assert( pEList!=0 );
  hasDistinct = distinct>=0;
  if( pOrderBy==0 && !hasDistinct ){
    codeOffset(v, p, iContinue);
  }

  /* Pull the requested columns.
  */
  if( nColumn>0 ){
    nResultCol = nColumn;
  }else{
    nResultCol = pEList->nExpr;
  }
  if( pDest->iMem==0 ){
    pDest->iMem = pParse->nMem+1;
    pDest->nMem = nResultCol;
    pParse->nMem += nResultCol;
  }else{ 
    assert( pDest->nMem==nResultCol );
  }
  regResult = pDest->iMem;
  if( nColumn>0 ){
    for(i=0; i<nColumn; i++){
      sqlite3VdbeAddOp3(v, OP_Column, srcTab, i, regResult+i);
    }
  }else if( eDest!=SRT_Exists ){
    /* If the destination is an EXISTS(...) expression, the actual
    ** values returned by the SELECT are not required.

#ifndef SQLITE_OMIT_SUBQUERY
    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
    ** then there should be a single item on the stack.  Write this
    ** item into the set table with bogus data.
    */
    case SRT_Set: {
      assert( nColumn==1 );
      p->affinity = sqlite3CompareAffinity(pEList->a[0].pExpr, pDest->affinity);
      if( pOrderBy ){
        /* At first glance you would think we could optimize out the
        ** ORDER BY in this case since the order of entries in the set
        ** does not matter.  But there might be a LIMIT clause, in which
        ** case the order does matter */
        pushOntoSorter(pParse, pOrderBy, p, regResult);
      }else{

      testcase( eDest==SRT_Output );
      if( pOrderBy ){
        int r1 = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
        pushOntoSorter(pParse, pOrderBy, p, r1);
        sqlite3ReleaseTempReg(pParse, r1);
      }else if( eDest==SRT_Coroutine ){
        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
      }else{
        sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, nColumn);
        sqlite3ExprCacheAffinityChange(pParse, regResult, nColumn);
      }
      break;
    }

  int addrContinue = sqlite3VdbeMakeLabel(v);  /* Jump here for next cycle */
  int addr;
  int iTab;
  int pseudoTab = 0;
  ExprList *pOrderBy = p->pOrderBy;

  int eDest = pDest->eDest;
  int iParm = pDest->iParm;

  int regRow;
  int regRowid;

  iTab = pOrderBy->iECursor;
  regRow = sqlite3GetTempReg(pParse);
  if( eDest==SRT_Output || eDest==SRT_Coroutine ){

#endif
    default: {
      int i;
      assert( eDest==SRT_Output || eDest==SRT_Coroutine ); 
      testcase( eDest==SRT_Output );
      testcase( eDest==SRT_Coroutine );
      for(i=0; i<nColumn; i++){
        assert( regRow!=pDest->iMem+i );
        sqlite3VdbeAddOp3(v, OP_Column, pseudoTab, i, pDest->iMem+i);
        if( i==0 ){
          sqlite3VdbeChangeP5(v, OPFLAG_CLEARCACHE);
        }
      }
      if( eDest==SRT_Output ){
        sqlite3VdbeAddOp2(v, OP_ResultRow, pDest->iMem, nColumn);
        sqlite3ExprCacheAffinityChange(pParse, pDest->iMem, nColumn);
      }else{
        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
      }
      break;
    }
  }
  sqlite3ReleaseTempReg(pParse, regRow);
  sqlite3ReleaseTempReg(pParse, regRowid);

  v = sqlite3GetVdbe(pParse);
  assert( v!=0 );  /* The VDBE already created by calling function */

  /* Create the destination temporary table if necessary
  */
  if( dest.eDest==SRT_EphemTab ){
    assert( p->pEList );
    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, dest.iParm, p->pEList->nExpr);
    sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
    dest.eDest = SRT_Table;
  }

  /* Make sure all SELECTs in the statement have the same number of elements
  ** in their result sets.
  */

        /* We can reuse a temporary table generated by a SELECT to our
        ** right.
        */
        assert( p->pRightmost!=p );  /* Can only happen for leftward elements
                                     ** of a 3-way or more compound */
        assert( p->pLimit==0 );      /* Not allowed on leftward elements */
        assert( p->pOffset==0 );     /* Not allowed on leftward elements */
        unionTab = dest.iParm;
      }else{
        /* We will need to create our own temporary table to hold the
        ** intermediate results.
        */
        unionTab = pParse->nTab++;
        assert( p->pOrderBy==0 );
        addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, unionTab, 0);

      p->pOffset = pOffset;
      p->iLimit = 0;
      p->iOffset = 0;

      /* Convert the data in the temporary table into whatever form
      ** it is that we currently need.
      */
      assert( unionTab==dest.iParm || dest.eDest!=priorOp );
      if( dest.eDest!=priorOp ){
        int iCont, iBreak, iStart;
        assert( p->pEList );
        if( dest.eDest==SRT_Output ){
          Select *pFirst = p;
          while( pFirst->pPrior ) pFirst = pFirst->pPrior;
          generateColumnNames(pParse, 0, pFirst->pEList);

      assert( p->addrOpenEphm[1] == -1 );
      p->addrOpenEphm[1] = addr;
      p->pPrior = 0;
      pLimit = p->pLimit;
      p->pLimit = 0;
      pOffset = p->pOffset;
      p->pOffset = 0;
      intersectdest.iParm = tab2;
      explainSetInteger(iSub2, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, p, &intersectdest);
      testcase( rc!=SQLITE_OK );
      pDelete = p->pPrior;
      p->pPrior = pPrior;
      if( p->nSelectRow>pPrior->nSelectRow ) p->nSelectRow = pPrior->nSelectRow;
      sqlite3ExprDelete(db, p->pLimit);

        pLoop->addrOpenEphm[i] = -1;
      }
    }
    sqlite3DbFree(db, pKeyInfo);
  }

multi_select_end:
  pDest->iMem = dest.iMem;
  pDest->nMem = dest.nMem;
  sqlite3SelectDelete(db, pDelete);
  return rc;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

/*
** Code an output subroutine for a coroutine implementation of a
** SELECT statment.
**
** The data to be output is contained in pIn->iMem.  There are
** pIn->nMem columns to be output.  pDest is where the output should
** be sent.
**
** regReturn is the number of the register holding the subroutine
** return address.
**
** If regPrev>0 then it is the first register in a vector that
** records the previous output.  mem[regPrev] is a flag that is false

  iContinue = sqlite3VdbeMakeLabel(v);

  /* Suppress duplicates for UNION, EXCEPT, and INTERSECT 
  */
  if( regPrev ){
    int j1, j2;
    j1 = sqlite3VdbeAddOp1(v, OP_IfNot, regPrev);
    j2 = sqlite3VdbeAddOp4(v, OP_Compare, pIn->iMem, regPrev+1, pIn->nMem,
                              (char*)pKeyInfo, p4type);
    sqlite3VdbeAddOp3(v, OP_Jump, j2+2, iContinue, j2+2);
    sqlite3VdbeJumpHere(v, j1);
    sqlite3ExprCodeCopy(pParse, pIn->iMem, regPrev+1, pIn->nMem);
    sqlite3VdbeAddOp2(v, OP_Integer, 1, regPrev);
  }
  if( pParse->db->mallocFailed ) return 0;

  /* Suppress the the first OFFSET entries if there is an OFFSET clause
  */
  codeOffset(v, p, iContinue);

  switch( pDest->eDest ){
    /* Store the result as data using a unique key.
    */
    case SRT_Table:
    case SRT_EphemTab: {
      int r1 = sqlite3GetTempReg(pParse);
      int r2 = sqlite3GetTempReg(pParse);
      testcase( pDest->eDest==SRT_Table );
      testcase( pDest->eDest==SRT_EphemTab );
      sqlite3VdbeAddOp3(v, OP_MakeRecord, pIn->iMem, pIn->nMem, r1);
      sqlite3VdbeAddOp2(v, OP_NewRowid, pDest->iParm, r2);
      sqlite3VdbeAddOp3(v, OP_Insert, pDest->iParm, r1, r2);
      sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
      sqlite3ReleaseTempReg(pParse, r2);
      sqlite3ReleaseTempReg(pParse, r1);
      break;
    }

#ifndef SQLITE_OMIT_SUBQUERY
    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
    ** then there should be a single item on the stack.  Write this
    ** item into the set table with bogus data.
    */
    case SRT_Set: {
      int r1;
      assert( pIn->nMem==1 );
      p->affinity = 
         sqlite3CompareAffinity(p->pEList->a[0].pExpr, pDest->affinity);
      r1 = sqlite3GetTempReg(pParse);
      sqlite3VdbeAddOp4(v, OP_MakeRecord, pIn->iMem, 1, r1, &p->affinity, 1);
      sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, 1);
      sqlite3VdbeAddOp2(v, OP_IdxInsert, pDest->iParm, r1);
      sqlite3ReleaseTempReg(pParse, r1);
      break;
    }

#if 0  /* Never occurs on an ORDER BY query */
    /* If any row exist in the result set, record that fact and abort.
    */
    case SRT_Exists: {
      sqlite3VdbeAddOp2(v, OP_Integer, 1, pDest->iParm);
      /* The LIMIT clause will terminate the loop for us */
      break;
    }
#endif

    /* If this is a scalar select that is part of an expression, then
    ** store the results in the appropriate memory cell and break out
    ** of the scan loop.
    */
    case SRT_Mem: {
      assert( pIn->nMem==1 );
      sqlite3ExprCodeMove(pParse, pIn->iMem, pDest->iParm, 1);
      /* The LIMIT clause will jump out of the loop for us */
      break;
    }
#endif /* #ifndef SQLITE_OMIT_SUBQUERY */

    /* The results are stored in a sequence of registers
    ** starting at pDest->iMem.  Then the co-routine yields.
    */
    case SRT_Coroutine: {
      if( pDest->iMem==0 ){
        pDest->iMem = sqlite3GetTempRange(pParse, pIn->nMem);
        pDest->nMem = pIn->nMem;
      }
      sqlite3ExprCodeMove(pParse, pIn->iMem, pDest->iMem, pDest->nMem);
      sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
      break;
    }

    /* If none of the above, then the result destination must be
    ** SRT_Output.  This routine is never called with any other
    ** destination other than the ones handled above or SRT_Output.
    **
    ** For SRT_Output, results are stored in a sequence of registers.  
    ** Then the OP_ResultRow opcode is used to cause sqlite3_step() to
    ** return the next row of result.
    */
    default: {
      assert( pDest->eDest==SRT_Output );
      sqlite3VdbeAddOp2(v, OP_ResultRow, pIn->iMem, pIn->nMem);
      sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, pIn->nMem);
      break;
    }
  }

  /* Jump to the end of the loop if the LIMIT is reached.
  */
  if( p->iLimit ){

  sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
  sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);

  /* Implement the main merge loop
  */
  sqlite3VdbeResolveLabel(v, labelCmpr);
  sqlite3VdbeAddOp4(v, OP_Permutation, 0, 0, 0, (char*)aPermute, P4_INTARRAY);
  sqlite3VdbeAddOp4(v, OP_Compare, destA.iMem, destB.iMem, nOrderBy,
                         (char*)pKeyMerge, P4_KEYINFO_HANDOFF);
  sqlite3VdbeAddOp3(v, OP_Jump, addrAltB, addrAeqB, addrAgtB);

  /* Release temporary registers
  */
  if( regPrev ){
    sqlite3ReleaseTempRange(pParse, regPrev, nOrderBy+1);

  }
  pTab = p->pSrc->a[0].pTab;
  pExpr = p->pEList->a[0].pExpr;
  assert( pTab && !pTab->pSelect && pExpr );

  if( IsVirtual(pTab) ) return 0;
  if( pExpr->op!=TK_AGG_FUNCTION ) return 0;
  if( pAggInfo->nFunc==0 ) return 0;
  if( (pAggInfo->aFunc[0].pFunc->flags&SQLITE_FUNC_COUNT)==0 ) return 0;
  if( pExpr->flags&EP_Distinct ) return 0;

  return pTab;
}

/*

  w.pParse = pParse;
  sqlite3WalkSelect(&w, pSelect);
#endif
}


/*
** This routine sets of a SELECT statement for processing.  The
** following is accomplished:
**
**     *  VDBE Cursor numbers are assigned to all FROM-clause terms.
**     *  Ephemeral Table objects are created for all FROM-clause subqueries.
**     *  ON and USING clauses are shifted into WHERE statements
**     *  Wildcards "*" and "TABLE.*" in result sets are expanded.
**     *  Identifiers in expression are matched to tables.

}

/*
** Reset the aggregate accumulator.
**
** The aggregate accumulator is a set of memory cells that hold
** intermediate results while calculating an aggregate.  This
** routine simply stores NULLs in all of those memory cells.

*/
static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){
  Vdbe *v = pParse->pVdbe;
  int i;
  struct AggInfo_func *pFunc;
  if( pAggInfo->nFunc+pAggInfo->nColumn==0 ){
    return;

**     pDest->eDest    Result
**     ------------    -------------------------------------------
**     SRT_Output      Generate a row of output (using the OP_ResultRow
**                     opcode) for each row in the result set.
**
**     SRT_Mem         Only valid if the result is a single column.
**                     Store the first column of the first result row
**                     in register pDest->iParm then abandon the rest
**                     of the query.  This destination implies "LIMIT 1".
**
**     SRT_Set         The result must be a single column.  Store each
**                     row of result as the key in table pDest->iParm. 
**                     Apply the affinity pDest->affinity before storing
**                     results.  Used to implement "IN (SELECT ...)".
**
**     SRT_Union       Store results as a key in a temporary table pDest->iParm.

**
**     SRT_Except      Remove results from the temporary table pDest->iParm.
**
**     SRT_Table       Store results in temporary table pDest->iParm.
**                     This is like SRT_EphemTab except that the table
**                     is assumed to already be open.
**
**     SRT_EphemTab    Create an temporary table pDest->iParm and store
**                     the result there. The cursor is left open after
**                     returning.  This is like SRT_Table except that
**                     this destination uses OP_OpenEphemeral to create
**                     the table first.
**
**     SRT_Coroutine   Generate a co-routine that returns a new row of
**                     results each time it is invoked.  The entry point
**                     of the co-routine is stored in register pDest->iParm.
**
**     SRT_Exists      Store a 1 in memory cell pDest->iParm if the result
**                     set is not empty.
**
**     SRT_Discard     Throw the results away.  This is used by SELECT
**                     statements within triggers whose only purpose is
**                     the side-effects of functions.
**
** This routine returns the number of errors.  If any errors are

  }else{
    addrSortIndex = -1;
  }

  /* If the output is destined for a temporary table, open that table.
  */
  if( pDest->eDest==SRT_EphemTab ){
    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pDest->iParm, pEList->nExpr);
  }

  /* Set the limiter.
  */
  iEnd = sqlite3VdbeMakeLabel(v);
  p->nSelectRow = (double)LARGEST_INT64;
  computeLimitRegisters(pParse, p, iEnd);

  }

  /* Aggregate and non-aggregate queries are handled differently */
  if( !isAgg && pGroupBy==0 ){
    ExprList *pDist = (isDistinct ? p->pEList : 0);

    /* Begin the database scan. */
    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pOrderBy, pDist, 0);
    if( pWInfo==0 ) goto select_end;
    if( pWInfo->nRowOut < p->nSelectRow ) p->nSelectRow = pWInfo->nRowOut;

    /* If sorting index that was created by a prior OP_OpenEphemeral 
    ** instruction ended up not being needed, then change the OP_OpenEphemeral
    ** into an OP_Noop.
    */

      /* Begin a loop that will extract all source rows in GROUP BY order.
      ** This might involve two separate loops with an OP_Sort in between, or
      ** it might be a single loop that uses an index to extract information
      ** in the right order to begin with.
      */
      sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset);
      pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pGroupBy, 0, 0);
      if( pWInfo==0 ) goto select_end;
      if( pGroupBy==0 ){
        /* The optimizer is able to deliver rows in group by order so
        ** we do not have to sort.  The OP_OpenEphemeral table will be
        ** cancelled later because we still need to use the pKeyInfo
        */
        pGroupBy = p->pGroupBy;

        }
  
        /* This case runs if the aggregate has no GROUP BY clause.  The
        ** processing is much simpler since there is only a single row
        ** of output.
        */
        resetAccumulator(pParse, &sAggInfo);
        pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pMinMax, 0, flag);
        if( pWInfo==0 ){
          sqlite3ExprListDelete(db, pDel);
          goto select_end;
        }
        updateAccumulator(pParse, &sAggInfo);
        if( !pMinMax && flag ){
          sqlite3VdbeAddOp2(v, OP_Goto, 0, pWInfo->iBreak);

#include <string.h>
#include <stdio.h>
#include <assert.h>
#include "sqlite3.h"
#include <ctype.h>
#include <stdarg.h>

#if !defined(_WIN32) && !defined(WIN32) && !defined(__OS2__)
# include <signal.h>
# if !defined(__RTP__) && !defined(_WRS_KERNEL)
#  include <pwd.h>
# endif
# include <unistd.h>
# include <sys/types.h>
#endif

#ifdef __OS2__
# include <unistd.h>
#endif

#ifdef HAVE_EDITLINE
# include <editline/editline.h>
#endif
#if defined(HAVE_READLINE) && HAVE_READLINE==1
# include <readline/readline.h>
# include <readline/history.h>
#endif

static int enableTimer = 0;

/* ctype macros that work with signed characters */
#define IsSpace(X)  isspace((unsigned char)X)
#define IsDigit(X)  isdigit((unsigned char)X)
#define ToLower(X)  (char)tolower((unsigned char)X)

#if !defined(_WIN32) && !defined(WIN32) && !defined(__OS2__) && !defined(__RTP__) && !defined(_WRS_KERNEL)
#include <sys/time.h>
#include <sys/resource.h>

/* Saved resource information for the beginning of an operation */
static struct rusage sBegin;

/*

/*
** Make sure the database is open.  If it is not, then open it.  If
** the database fails to open, print an error message and exit.
*/
static void open_db(struct callback_data *p){
  if( p->db==0 ){

    sqlite3_open(p->zDbFilename, &p->db);
    db = p->db;
    if( db && sqlite3_errcode(db)==SQLITE_OK ){
      sqlite3_create_function(db, "shellstatic", 0, SQLITE_UTF8, 0,
          shellstaticFunc, 0, 0);
    }
    if( db==0 || SQLITE_OK!=sqlite3_errcode(db) ){

    enableTimer = booleanValue(azArg[1]);
  }else
  
  if( c=='t' && strncmp(azArg[0], "trace", n)==0 && nArg>1 ){
    open_db(p);
    output_file_close(p->traceOut);
    p->traceOut = output_file_open(azArg[1]);
#ifndef SQLITE_OMIT_TRACE
    if( p->traceOut==0 ){
      sqlite3_trace(p->db, 0, 0);
    }else{
      sqlite3_trace(p->db, sql_trace_callback, p->traceOut);
    }
#endif
  }else

** Return a pathname which is the user's home directory.  A
** 0 return indicates an error of some kind.
*/
static char *find_home_dir(void){
  static char *home_dir = NULL;
  if( home_dir ) return home_dir;

#if !defined(_WIN32) && !defined(WIN32) && !defined(__OS2__) && !defined(_WIN32_WCE) && !defined(__RTP__) && !defined(_WRS_KERNEL)

  struct passwd *pwent;
  uid_t uid = getuid();
  if( (pwent=getpwuid(uid)) != NULL) {
    home_dir = pwent->pw_dir;

  }
#endif

#if defined(_WIN32_WCE)
  /* Windows CE (arm-wince-mingw32ce-gcc) does not provide getenv()
   */
  home_dir = "/";
#else

#if defined(_WIN32) || defined(WIN32) || defined(__OS2__)
  if (!home_dir) {
    home_dir = getenv("USERPROFILE");
  }
#endif

  if (!home_dir) {
    home_dir = getenv("HOME");
  }

#if defined(_WIN32) || defined(WIN32) || defined(__OS2__)
  if (!home_dir) {
    char *zDrive, *zPath;
    int n;
    zDrive = getenv("HOMEDRIVE");
    zPath = getenv("HOMEPATH");
    if( zDrive && zPath ){
      n = strlen30(zDrive) + strlen30(zPath) + 1;

    home_dir = find_home_dir();
    if( home_dir==0 ){
#if !defined(__RTP__) && !defined(_WRS_KERNEL)
      fprintf(stderr,"%s: Error: cannot locate your home directory\n", Argv0);
#endif
      return 1;
    }

    zBuf = sqlite3_mprintf("%s/.sqliterc",home_dir);
    sqliterc = zBuf;
  }
  in = fopen(sqliterc,"rb");
  if( in ){
    if( stdin_is_interactive ){
      fprintf(stderr,"-- Loading resources from %s\n",sqliterc);

      }else{
        fprintf(stderr, "no such VFS: \"%s\"\n", argv[i]);
        exit(1);
      }
    }
  }
  if( i<argc ){
#if defined(SQLITE_OS_OS2) && SQLITE_OS_OS2
    data.zDbFilename = (const char *)convertCpPathToUtf8( argv[i++] );
#else
    data.zDbFilename = argv[i++];
#endif
  }else{
#ifndef SQLITE_OMIT_MEMORYDB
    data.zDbFilename = ":memory:";
#else
    data.zDbFilename = 0;
#endif
  }

** CAPI3REF: Database Connection Handle
** KEYWORDS: {database connection} {database connections}
**
** Each open SQLite database is represented by a pointer to an instance of
** the opaque structure named "sqlite3".  It is useful to think of an sqlite3
** pointer as an object.  The [sqlite3_open()], [sqlite3_open16()], and
** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]

** is its destructor.  There are many other interfaces (such as
** [sqlite3_prepare_v2()], [sqlite3_create_function()], and
** [sqlite3_busy_timeout()] to name but three) that are methods on an
** sqlite3 object.
*/
typedef struct sqlite3 sqlite3;

/*

#ifdef SQLITE_OMIT_FLOATING_POINT
# define double sqlite3_int64
#endif

/*
** CAPI3REF: Closing A Database Connection
**

** ^The sqlite3_close() routine is the destructor for the [sqlite3] object.
** ^Calls to sqlite3_close() return SQLITE_OK if the [sqlite3] object is
** successfully destroyed and all associated resources are deallocated.

**











** Applications must [sqlite3_finalize | finalize] all [prepared statements]
** and [sqlite3_blob_close | close] all [BLOB handles] associated with

** the [sqlite3] object prior to attempting to close the object.  ^If
** sqlite3_close() is called on a [database connection] that still has
** outstanding [prepared statements] or [BLOB handles], then it returns
** SQLITE_BUSY.


**
** ^If [sqlite3_close()] is invoked while a transaction is open,
** the transaction is automatically rolled back.
**
** The C parameter to [sqlite3_close(C)] must be either a NULL

** pointer or an [sqlite3] object pointer obtained
** from [sqlite3_open()], [sqlite3_open16()], or
** [sqlite3_open_v2()], and not previously closed.
** ^Calling sqlite3_close() with a NULL pointer argument is a 
** harmless no-op.
*/
int sqlite3_close(sqlite3 *);


/*
** The type for a callback function.
** This is legacy and deprecated.  It is included for historical
** compatibility and is not documented.
*/
typedef int (*sqlite3_callback)(void*,int,char**, char**);

** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).
**
** ^The third argument is the value to bind to the parameter.
**
** ^(In those routines that have a fourth argument, its value is the
** number of bytes in the parameter.  To be clear: the value is the
** number of <u>bytes</u> in the value, not the number of characters.)^
** ^If the fourth parameter is negative, the length of the string is

** the number of bytes up to the first zero terminator.


** If a non-negative fourth parameter is provided to sqlite3_bind_text()
** or sqlite3_bind_text16() then that parameter must be the byte offset
** where the NUL terminator would occur assuming the string were NUL
** terminated.  If any NUL characters occur at byte offsets less than 
** the value of the fourth parameter then the resulting string value will
** contain embedded NULs.  The result of expressions involving strings
** with embedded NULs is undefined.

** they return.  Hence, the calling function can deallocate or
** modify the text after they return without harm.
** ^The sqlite3_result_error_code() function changes the error code
** returned by SQLite as a result of an error in a function.  ^By default,
** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
**
** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
** indicating that a string or BLOB is too long to represent.
**
** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
** indicating that a memory allocation failed.
**
** ^The sqlite3_result_int() interface sets the return value
** of the application-defined function to be the 32-bit signed integer
** value given in the 2nd argument.
** ^The sqlite3_result_int64() interface sets the return value
** of the application-defined function to be the 64-bit signed integer
** value given in the 2nd argument.

**
** The SQLite source code contains multiple implementations
** of these mutex routines.  An appropriate implementation
** is selected automatically at compile-time.  ^(The following
** implementations are available in the SQLite core:
**
** <ul>
** <li>   SQLITE_MUTEX_OS2
** <li>   SQLITE_MUTEX_PTHREADS
** <li>   SQLITE_MUTEX_W32
** <li>   SQLITE_MUTEX_NOOP
** </ul>)^
**
** ^The SQLITE_MUTEX_NOOP implementation is a set of routines
** that does no real locking and is appropriate for use in
** a single-threaded application.  ^The SQLITE_MUTEX_OS2,
** SQLITE_MUTEX_PTHREADS, and SQLITE_MUTEX_W32 implementations
** are appropriate for use on OS/2, Unix, and Windows.
**
** ^(If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor
** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex
** implementation is included with the library. In this case the
** application must supply a custom mutex implementation using the
** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function
** before calling sqlite3_initialize() or any other public sqlite3_

/*
** Exactly one of the following macros must be defined in order to
** specify which memory allocation subsystem to use.
**
**     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
**     SQLITE_WIN32_MALLOC           // Use Win32 native heap API

**     SQLITE_MEMDEBUG               // Debugging version of system malloc()
**
** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
** assert() macro is enabled, each call into the Win32 native heap subsystem
** will cause HeapValidate to be called.  If heap validation should fail, an
** assertion will be triggered.
**
** (Historical note:  There used to be several other options, but we've
** pared it down to just these three.)
**
** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as
** the default.
*/
#if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_WIN32_MALLOC)+defined(SQLITE_MEMDEBUG)>1



# error "At most one of the following compile-time configuration options\

 is allows: SQLITE_SYSTEM_MALLOC, SQLITE_WIN32_MALLOC, SQLITE_MEMDEBUG"

#endif
#if defined(SQLITE_SYSTEM_MALLOC)+defined(SQLITE_WIN32_MALLOC)+defined(SQLITE_MEMDEBUG)==0



# define SQLITE_SYSTEM_MALLOC 1
#endif

/*
** If SQLITE_MALLOC_SOFT_LIMIT is not zero, then try to keep the
** sizes of memory allocations below this value where possible.
*/

** than being distinct from one another.
*/
#define SQLITE_MAGIC_OPEN     0xa029a697  /* Database is open */
#define SQLITE_MAGIC_CLOSED   0x9f3c2d33  /* Database is closed */
#define SQLITE_MAGIC_SICK     0x4b771290  /* Error and awaiting close */
#define SQLITE_MAGIC_BUSY     0xf03b7906  /* Database currently in use */
#define SQLITE_MAGIC_ERROR    0xb5357930  /* An SQLITE_MISUSE error occurred */


/*
** Each SQL function is defined by an instance of the following
** structure.  A pointer to this structure is stored in the sqlite.aFunc
** hash table.  When multiple functions have the same name, the hash table
** points to a linked list of these structures.
*/

                         ** TK_REGISTER: register number
                         ** TK_TRIGGER: 1 -> new, 0 -> old */
  ynVar iColumn;         /* TK_COLUMN: column index.  -1 for rowid.
                         ** TK_VARIABLE: variable number (always >= 1). */
  i16 iAgg;              /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
  i16 iRightJoinTable;   /* If EP_FromJoin, the right table of the join */
  u8 flags2;             /* Second set of flags.  EP2_... */
  u8 op2;                /* If a TK_REGISTER, the original value of Expr.op */
                         /* If TK_COLUMN, the value of p5 for OP_Column */

  AggInfo *pAggInfo;     /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
  Table *pTab;           /* Table for TK_COLUMN expressions. */
#if SQLITE_MAX_EXPR_DEPTH>0
  int nHeight;           /* Height of the tree headed by this node */
#endif
};

    struct {
      int nIn;              /* Number of entries in aInLoop[] */
      struct InLoop {
        int iCur;              /* The VDBE cursor used by this IN operator */
        int addrInTop;         /* Top of the IN loop */
      } *aInLoop;           /* Information about each nested IN operator */
    } in;                 /* Used when plan.wsFlags&WHERE_IN_ABLE */

  } u;

  /* The following field is really not part of the current level.  But
  ** we need a place to cache virtual table index information for each
  ** virtual table in the FROM clause and the WhereLevel structure is
  ** a convenient place since there is one WhereLevel for each FROM clause
  ** element.

/*
** A structure used to customize the behavior of sqlite3Select(). See
** comments above sqlite3Select() for details.
*/
typedef struct SelectDest SelectDest;
struct SelectDest {
  u8 eDest;         /* How to dispose of the results */
  u8 affinity;      /* Affinity used when eDest==SRT_Set */
  int iParm;        /* A parameter used by the eDest disposal method */
  int iMem;         /* Base register where results are written */
  int nMem;         /* Number of registers allocated */
};

/*
** During code generation of statements that do inserts into AUTOINCREMENT 
** tables, the following information is attached to the Table.u.autoInc.p
** pointer of each autoincrement table to record some side information that
** the code generator needs.  We have to keep per-table autoincrement

#define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
#define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
#define OPFLAG_APPEND        0x08    /* This is likely to be an append */
#define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
#define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */
#define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
#define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */



/*
 * Each trigger present in the database schema is stored as an instance of
 * struct Trigger. 
 *
 * Pointers to instances of struct Trigger are stored in two ways.
 * 1. In the "trigHash" hash table (part of the sqlite3* that represents the 

/*
** Context pointer passed down through the tree-walk.
*/
struct Walker {
  int (*xExprCallback)(Walker*, Expr*);     /* Callback for expressions */
  int (*xSelectCallback)(Walker*,Select*);  /* Callback for SELECTs */
  Parse *pParse;                            /* Parser context.  */

  union {                                   /* Extra data for callback */
    NameContext *pNC;                          /* Naming context */
    int i;                                     /* Integer value */
    SrcList *pSrcList;                         /* FROM clause */

  } u;
};

/* Forward declarations */
int sqlite3WalkExpr(Walker*, Expr*);
int sqlite3WalkExprList(Walker*, ExprList*);
int sqlite3WalkSelect(Walker*, Select*);

int sqlite3IsReadOnly(Parse*, Table*, int);
void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
Expr *sqlite3LimitWhere(Parse *, SrcList *, Expr *, ExprList *, Expr *, Expr *, char *);
#endif
void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**,ExprList*,u16);

void sqlite3WhereEnd(WhereInfo*);
int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
void sqlite3ExprCodeMove(Parse*, int, int, int);
void sqlite3ExprCodeCopy(Parse*, int, int, int);
void sqlite3ExprCacheStore(Parse*, int, int, int);
void sqlite3ExprCachePush(Parse*);

void sqlite3Vacuum(Parse*);
int sqlite3RunVacuum(char**, sqlite3*);
char *sqlite3NameFromToken(sqlite3*, Token*);
int sqlite3ExprCompare(Expr*, Expr*);
int sqlite3ExprListCompare(ExprList*, ExprList*);
void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);

Vdbe *sqlite3GetVdbe(Parse*);
void sqlite3PrngSaveState(void);
void sqlite3PrngRestoreState(void);
void sqlite3PrngResetState(void);
void sqlite3RollbackAll(sqlite3*,int);
void sqlite3CodeVerifySchema(Parse*, int);
void sqlite3CodeVerifyNamedSchema(Parse*, const char *zDb);
void sqlite3BeginTransaction(Parse*, int);
void sqlite3CommitTransaction(Parse*);
void sqlite3RollbackTransaction(Parse*);
void sqlite3Savepoint(Parse*, int, Token*);
void sqlite3CloseSavepoints(sqlite3 *);

int sqlite3ExprIsConstant(Expr*);
int sqlite3ExprIsConstantNotJoin(Expr*);
int sqlite3ExprIsConstantOrFunction(Expr*);
int sqlite3ExprIsInteger(Expr*, int*);
int sqlite3ExprCanBeNull(const Expr*);
void sqlite3ExprCodeIsNullJump(Vdbe*, const Expr*, int, int);
int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);

  int objc,
  Tcl_Obj *CONST objv[]
){
  int i;
  sqlite3 *db;
  const char *zOpt;
  int onoff;
  int mask;
  static const struct {
    const char *zOptName;
    int mask;
  } aOpt[] = {
    { "all",              SQLITE_OptMask        },
    { "query-flattener",  SQLITE_QueryFlattener },
    { "column-cache",     SQLITE_ColumnCache    },

  rc = sqlite3_declare_vtab(db, Tcl_GetString(objv[2]));
  if( rc!=SQLITE_OK ){
    Tcl_SetResult(interp, (char *)sqlite3_errmsg(db), TCL_VOLATILE);
    return TCL_ERROR;
  }
  return TCL_OK;
}
























#endif /* ifndef SQLITE_OMIT_VIRTUALTABLE */

/*
** Register commands with the TCL interpreter.
*/
int Sqlitetest8_Init(Tcl_Interp *interp){
#ifndef SQLITE_OMIT_VIRTUALTABLE
  static struct {
     char *zName;
     Tcl_ObjCmdProc *xProc;
     void *clientData;
  } aObjCmd[] = {
     { "register_echo_module",   register_echo_module, 0 },

     { "sqlite3_declare_vtab",   declare_vtab, 0 },
  };
  int i;
  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, 
        aObjCmd[i].xProc, aObjCmd[i].clientData, 0);
  }
#endif

#endif

#if defined(SQLITE_ENABLE_FTS3) && defined(SQLITE_ENABLE_FTS4_UNICODE61)
  Tcl_SetVar2(interp, "sqlite_options", "fts3_unicode", "1", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "fts3_unicode", "0", TCL_GLOBAL_ONLY);
#endif







#ifdef SQLITE_OMIT_GET_TABLE
  Tcl_SetVar2(interp, "sqlite_options", "gettable", "0", TCL_GLOBAL_ONLY);
#else
  Tcl_SetVar2(interp, "sqlite_options", "gettable", "1", TCL_GLOBAL_ONLY);
#endif

  LINKVAR( MAX_DEFAULT_PAGE_SIZE );

  {
    static const int cv_TEMP_STORE = SQLITE_TEMP_STORE;
    Tcl_LinkVar(interp, "TEMP_STORE", (char *)&(cv_TEMP_STORE),
                TCL_LINK_INT | TCL_LINK_READ_ONLY);
  }















}


/*
** Register commands with the TCL interpreter.
*/
int Sqliteconfig_Init(Tcl_Interp *interp){
  set_options(interp);
  return TCL_OK;
}

    sqlite3_result_error_nomem(pCtx);
  }else{
    testHexToBin(zIn, zOut);
    sqlite3_result_text16le(pCtx, zOut, n/2, sqlite3_free);
  }
}
#endif






































static int registerTestFunctions(sqlite3 *db){
  static const struct {
     char *zName;
     signed char nArg;
     unsigned char eTextRep; /* 1: UTF-16.  0: UTF-8 */
     void (*xFunc)(sqlite3_context*,int,sqlite3_value **);

    { "test_destructor_count", 0, SQLITE_UTF8, test_destructor_count},
    { "test_auxdata",         -1, SQLITE_UTF8, test_auxdata},
    { "test_error",            1, SQLITE_UTF8, test_error},
    { "test_error",            2, SQLITE_UTF8, test_error},
    { "test_eval",             1, SQLITE_UTF8, test_eval},
    { "test_isolation",        2, SQLITE_UTF8, test_isolation},
    { "test_counter",          1, SQLITE_UTF8, counterFunc},

  };
  int i;

  for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
    sqlite3_create_function(db, aFuncs[i].zName, aFuncs[i].nArg,
        aFuncs[i].eTextRep, 0, aFuncs[i].xFunc, 0, 0);
  }

  const char *zName,         /* Name of file to be opened */
  sqlite3_file *pConn,       /* Fill in this file descriptor */
  int flags,                 /* Flags to control the opening */
  int *pOutFlags             /* Flags showing results of opening */
){
  int rc = SQLITE_OK;                  /* Result code */
  multiplexConn *pMultiplexOpen;       /* The new multiplex file descriptor */
  multiplexGroup *pGroup;              /* Corresponding multiplexGroup object */
  sqlite3_file *pSubOpen = 0;                    /* Real file descriptor */
  sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
  int nName;
  int sz;
  char *zToFree = 0;

  UNUSED_PARAMETER(pVfs);
  memset(pConn, 0, pVfs->szOsFile);
  assert( zName || (flags & SQLITE_OPEN_DELETEONCLOSE) );

  /* We need to create a group structure and manage

#define sqlite3_mutex_notheld(X)  ((void)(X),1)
#endif /* SQLITE_THREADSAFE==0 */


/*
** Figure out if we are dealing with Unix, Windows, or some other
** operating system.  After the following block of preprocess macros,
** all of SQLITE_OS_UNIX, SQLITE_OS_WIN, SQLITE_OS_OS2, and SQLITE_OS_OTHER 
** will defined to either 1 or 0.  One of the four will be 1.  The other 
** three will be 0.
*/
#if defined(SQLITE_OS_OTHER)
# if SQLITE_OS_OTHER==1
#   undef SQLITE_OS_UNIX
#   define SQLITE_OS_UNIX 0
#   undef SQLITE_OS_WIN
#   define SQLITE_OS_WIN 0
#   undef SQLITE_OS_OS2
#   define SQLITE_OS_OS2 0
# else
#   undef SQLITE_OS_OTHER
# endif
#endif
#if !defined(SQLITE_OS_UNIX) && !defined(SQLITE_OS_OTHER)
# define SQLITE_OS_OTHER 0
# ifndef SQLITE_OS_WIN
#   if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) \
                       || defined(__MINGW32__) || defined(__BORLANDC__)
#     define SQLITE_OS_WIN 1
#     define SQLITE_OS_UNIX 0
#     define SQLITE_OS_OS2 0
#   elif defined(__EMX__) || defined(_OS2) || defined(OS2) \
                          || defined(_OS2_) || defined(__OS2__)
#     define SQLITE_OS_WIN 0
#     define SQLITE_OS_UNIX 0
#     define SQLITE_OS_OS2 1
#   else
#     define SQLITE_OS_WIN 0
#     define SQLITE_OS_UNIX 1
#     define SQLITE_OS_OS2 0
#  endif
# else
#  define SQLITE_OS_UNIX 0
#  define SQLITE_OS_OS2 0
# endif
#else
# ifndef SQLITE_OS_WIN
#  define SQLITE_OS_WIN 0
# endif
#endif

/*
** 2012 April 10
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This module implements a VIRTUAL TABLE that can be used to search
** a large vocabulary for close matches.  For example, this virtual
** table can be used to suggest corrections to misspelled words.  Or,
** it could be used with FTS4 to do full-text search using potentially
** misspelled words.
**
** Create an instance of the virtual table this way:
**
**    CREATE VIRTUAL TABLE demo USING spellfix1;
**
** The "spellfix1" term is the name of this module.  The "demo" is the
** name of the virtual table you will be creating.  The table is initially
** empty.  You have to populate it with your vocabulary.  Suppose you
** have a list of words in a table named "big_vocabulary".  Then do this:
**
**    INSERT INTO demo(word) SELECT word FROM big_vocabulary;
**
** If you intend to use this virtual table in cooperation with an FTS4
** table (for spelling correctly of search terms) then you can extract
** the vocabulary using an fts3aux table:
**
**    INSERT INTO demo(word) SELECT term FROM search_aux WHERE col='*';
**
** You can also provide the virtual table with a "rank" for each word.
** The "rank" is an estimate of how common the word is.  Larger numbers
** mean the word is more common.  If you omit the rank when populating
** the table, then a rank of 1 is assumed.  But if you have rank 
** information, you can supply it and the virtual table will show a
** slight preference for selecting more commonly used terms.  To
** populate the rank from an fts4aux table "search_aux" do something
** like this:
**
**    INSERT INTO demo(word,rank)
**        SELECT term, documents FROM search_aux WHERE col='*';
**
** To query the virtual table, include a MATCH operator in the WHERE
** clause.  For example:
**
**    SELECT word FROM demo WHERE word MATCH 'kennasaw';
**
** Using a dataset of American place names (derived from
** http://geonames.usgs.gov/domestic/download_data.htm) the query above
** returns 20 results beginning with:
**
**    kennesaw
**    kenosha
**    kenesaw
**    kenaga
**    keanak
**
** If you append the character '*' to the end of the pattern, then
** a prefix search is performed.  For example:
**
**    SELECT word FROM demo WHERE word MATCH 'kennes*';
**
** Yields 20 results beginning with:
**
**    kennesaw
**    kennestone
**    kenneson
**    kenneys
**    keanes
**    keenes
**
** The virtual table actually has a unique rowid with five columns plus three
** extra hidden columns.  The columns are as follows:
**
**    rowid         A unique integer number associated with each
**                  vocabulary item in the table.  This can be used
**                  as a foreign key on other tables in the database.
**
**    word          The text of the word that matches the pattern.
**                  Both word and pattern can contains unicode characters
**                  and can be mixed case.
**
**    rank          This is the rank of the word, as specified in the
**                  original INSERT statement.
**
**    distance      This is an edit distance or Levensthein distance going
**                  from the pattern to the word.
**
**    langid        This is the language-id of the word.  All queries are
**                  against a single language-id, which defaults to 0.
**                  For any given query this value is the same on all rows.
**
**    score         The score is a combination of rank and distance.  The
**                  idea is that a lower score is better.  The virtual table
**                  attempts to find words with the lowest score and 
**                  by default (unless overridden by ORDER BY) returns
**                  results in order of increasing score.
**
**    top           (HIDDEN)  For any query, this value is the same on all
**                  rows.  It is an integer which is the maximum number of
**                  rows that will be output.  The actually number of rows
**                  output might be less than this number, but it will never
**                  be greater.  The default value for top is 20, but that
**                  can be changed for each query by including a term of
**                  the form "top=N" in the WHERE clause of the query.
**
**    scope         (HIDDEN)  For any query, this value is the same on all
**                  rows.  The scope is a measure of how widely the virtual
**                  table looks for matching words.  Smaller values of
**                  scope cause a broader search.  The scope is normally
**                  choosen automatically and is capped at 4.  Applications
**                  can change the scope by including a term of the form
**                  "scope=N" in the WHERE clause of the query.  Increasing
**                  the scope will make the query run faster, but will reduce
**                  the possible corrections.
**
**    srchcnt       (HIDDEN)  For any query, this value is the same on all
**                  rows.  This value is an integer which is the number of
**                  of words examined using the edit-distance algorithm to
**                  find the top matches that are ultimately displayed.  This
**                  value is for diagnostic use only.
**
**    soundslike    (HIDDEN)  When inserting vocabulary entries, this field
**                  can be set to an spelling that matches what the word
**                  sounds like.  See the DEALING WITH UNUSUAL AND DIFFICULT
**                  SPELLINGS section below for details.
**
** When inserting into or updating the virtual table, only the rowid, word,
** rank, and langid may be changes.  Any attempt to set or modify the values
** of distance, score, top, scope, or srchcnt is silently ignored.
**
** ALGORITHM
**
** A shadow table named "%_vocab" (where the % is replaced by the name of
** the virtual table; Ex: "demo_vocab" for the "demo" virtual table) is
** constructed with these columns:
**
**    id            The unique id (INTEGER PRIMARY KEY)
**
**    rank          The rank of word.
**
**    langid        The language id for this entry.
**
**    word          The original UTF8 text of the vocabulary word
**
**    k1            The word transliterated into lower-case ASCII.  
**                  There is a standard table of mappings from non-ASCII
**                  characters into ASCII.  Examples: "æ" -> "ae",
**                  "þ" -> "th", "ß" -> "ss", "á" -> "a", ...  The
**                  accessory function spellfix1_translit(X) will do
**                  the non-ASCII to ASCII mapping.  The built-in lower(X)
**                  function will convert to lower-case.  Thus:
**                  k1 = lower(spellfix1_translit(word)).
**
**    k2            This field holds a phonetic code derived from k1.  Letters
**                  that have similar sounds are mapped into the same symbol.
**                  For example, all vowels and vowel clusters become the
**                  single symbol "A".  And the letters "p", "b", "f", and
**                  "v" all become "B".  All nasal sounds are represented
**                  as "N".  And so forth.  The mapping is base on
**                  ideas found in Soundex, Metaphone, and other
**                  long-standing phonetic matching systems.  This key can
**                  be generated by the function spellfix1_charclass(X).  
**                  Hence: k2 = spellfix1_charclass(k1)
**
** There is also a function for computing the Wagner edit distance or the
** Levenshtein distance between a pattern and a word.  This function
** is exposed as spellfix1_editdist(X,Y).  The edit distance function
** returns the "cost" of converting X into Y.  Some transformations
** cost more than others.  Changing one vowel into a different vowel,
** for example is relatively cheap, as is doubling a constant, or
** omitting the second character of a double-constant.  Other transformations
** or more expensive.  The idea is that the edit distance function returns
** a low cost of words that are similar and a higher cost for words
** that are futher apart.  In this implementation, the maximum cost
** of any single-character edit (delete, insert, or substitute) is 100,
** with lower costs for some edits (such as transforming vowels).
**
** The "score" for a comparison is the edit distance between the pattern
** and the word, adjusted down by the base-2 logorithm of the word rank.
** For example, a match with distance 100 but rank 1000 would have a
** score of 122 (= 100 - log2(1000) + 32) where as a match with distance
** 100 with a rank of 1 would have a score of 131 (100 - log2(1) + 32).
** (NB:  The constant 32 is added to each score to keep it from going
** negative in case the edit distance is zero.)  In this way, frequently
** used words get a slightly lower cost which tends to move them toward
** the top of the list of alternative spellings.
**
** A straightforward implementation of a spelling corrector would be
** to compare the search term against every word in the vocabulary
** and select the 20 with the lowest scores.  However, there will 
** typically be hundreds of thousands or millions of words in the
** vocabulary, and so this approach is not fast enough.
**
** Suppose the term that is being spell-corrected is X.  To limit
** the search space, X is converted to a k2-like key using the
** equivalent of:
**
**    key = spellfix1_charclass(lower(spellfix1_translit(X)))
**
** This key is then limited to "scope" characters.  The default scope
** value is 4, but an alternative scope can be specified using the
** "scope=N" term in the WHERE clause.  After the key has been truncated,
** the edit distance is run against every term in the vocabulary that
** has a k2 value that begins with the abbreviated key.
**
** For example, suppose the input word is "Paskagula".  The phonetic 
** key is "BACACALA" which is then truncated to 4 characters "BACA".
** The edit distance is then run on the 4980 entries (out of
** 272,597 entries total) of the vocabulary whose k2 values begin with
** BACA, yielding "Pascagoula" as the best match.
** 
** Only terms of the vocabulary with a matching langid are searched.
** Hence, the same table can contain entries from multiple languages
** and only the requested language will be used.  The default langid
** is 0.
**
** DEALING WITH UNUSUAL AND DIFFICULT SPELLINGS
**
** The algorithm above works quite well for most cases, but there are
** exceptions.  These exceptions can be dealt with by making additional
** entries in the virtual table using the "soundslike" column.
**
** For example, many words of Greek origin begin with letters "ps" where
** the "p" is silent.  Ex:  psalm, pseudonym, psoriasis, psyche.  In
** another example, many Scottish surnames can be spelled with an
** initial "Mac" or "Mc".  Thus, "MacKay" and "McKay" are both pronounced
** the same.
**
** Accommodation can be made for words that are not spelled as they
** sound by making additional entries into the virtual table for the
** same word, but adding an alternative spelling in the "soundslike"
** column.  For example, the canonical entry for "psalm" would be this:
**
**   INSERT INTO demo(word) VALUES('psalm');
**
** To enhance the ability to correct the spelling of "salm" into
** "psalm", make an addition entry like this:
**
**   INSERT INTO demo(word,soundslike) VALUES('psalm','salm');
**
** It is ok to make multiple entries for the same word as long as
** each entry has a different soundslike value.  Note that if no
** soundslike value is specified, the soundslike defaults to the word
** itself.
**
** Listed below are some cases where it might make sense to add additional
** soundslike entries.  The specific entries will depend on the application
** and the target language.
**
**   *   Silent "p" in words beginning with "ps":  psalm, psyche
**
**   *   Silent "p" in words beginning with "pn":  pneumonia, pneumatic
**
**   *   Silent "p" in words beginning with "pt":  pterodactyl, ptolemaic
**
**   *   Silent "d" in words beginning with "dj":  djinn, Djikarta
**
**   *   Silent "k" in words beginning with "kn":  knight, Knuthson
**
**   *   Silent "g" in words beginning with "gn":  gnarly, gnome, gnat
**
**   *   "Mac" versus "Mc" beginning Scottish surnames
**
**   *   "Tch" sounds in Slavic words:  Tchaikovsky vs. Chaykovsky
**
**   *   The letter "j" pronounced like "h" in Spanish:  LaJolla
**
**   *   Words beginning with "wr" versus "r":  write vs. rite
**
**   *   Miscellanous problem words such as "debt", "tsetse",
**       "Nguyen", "Van Nuyes".
*/
#if SQLITE_CORE
# include "sqliteInt.h"
#else
# include <string.h>
# include <stdio.h>
# include <stdlib.h>
# include "sqlite3ext.h"
  SQLITE_EXTENSION_INIT1
#endif /* !SQLITE_CORE */


/*
** Character classes for ASCII characters:
**
**   0   ''        Silent letters:   H W
**   1   'A'       Any vowel:   A E I O U (Y)
**   2   'B'       A bilabeal stop or fricative:  B F P V
**   3   'C'       Other fricatives or back stops:  C G J K Q S X Z
**   4   'D'       Alveolar stops:  D T
**   5   'H'       Letter H at the beginning of a word
**   6   'L'       Glides:  L R

**   7   'M'       Nasals:  M N
**   8   'W'       Letter W at the beginning of a word
**   9   'Y'       Letter Y at the beginning of a word.
**   10  '9'       A digit: 0 1 2 3 4 5 6 7 8 9
**   11  ' '       White space
**   12  '?'       Other.
*/
#define CCLASS_SILENT         0
#define CCLASS_VOWEL          1
#define CCLASS_B              2
#define CCLASS_C              3
#define CCLASS_D              4
#define CCLASS_H              5
#define CCLASS_L              6

#define CCLASS_M              7
#define CCLASS_W              8
#define CCLASS_Y              9
#define CCLASS_DIGIT         10
#define CCLASS_SPACE         11
#define CCLASS_OTHER         12

/*
** The following table gives the character class for non-initial ASCII
** characters.
*/
static const unsigned char midClass[] = {
          /* x0  x1  x2  x3  x4  x5  x6  x7    x8  x9  xa  xb  xc  xd  xe  xf */
  /* 0x */   12, 12, 12, 12, 12, 12, 12, 12,   12, 11, 11, 12, 11, 12, 12, 12,
  /* 1x */   12, 12, 12, 12, 12, 12, 12, 12,   12, 12, 12, 12, 12, 12, 12, 12,
  /* 2x */   11, 12, 12, 12, 12, 12, 12, 12,   12, 12, 12, 12, 12, 12, 12, 12,
  /* 3x */   10, 10, 10, 10, 10, 10, 10, 10,   10, 10, 12, 12, 12, 12, 12, 12,
  /* 4x */   12,  1,  2,  3,  4,  1,  2,  3,    0,  1,  3,  3,  6,  7,  7,  1,
  /* 5x */    2,  3,  6,  3,  4,  1,  2,  0,    3,  1,  3, 12, 12, 12, 12, 12,
  /* 6x */   12,  1,  2,  3,  4,  1,  2,  3,    0,  1,  3,  3,  6,  7,  7,  1,
  /* 7x */    2,  3,  6,  3,  4,  1,  2,  0,    3,  1,  3, 12, 12, 12, 12, 12,



































};

/* 
** This tables gives the character class for ASCII characters that form the
** initial character of a word.  The only difference from midClass is with
** the letters H, W, and Y.
*/
static const unsigned char initClass[] = {

          /* x0  x1  x2  x3  x4  x5  x6  x7    x8  x9  xa  xb  xc  xd  xe  xf */
  /* 0x */   12, 12, 12, 12, 12, 12, 12, 12,   12, 11, 11, 12, 11, 12, 12, 12,
  /* 1x */   12, 12, 12, 12, 12, 12, 12, 12,   12, 12, 12, 12, 12, 12, 12, 12,
  /* 2x */   11, 12, 12, 12, 12, 12, 12, 12,   12, 12, 12, 12, 12, 12, 12, 12,
  /* 3x */   10, 10, 10, 10, 10, 10, 10, 10,   10, 10, 12, 12, 12, 12, 12, 12,
  /* 4x */   12,  1,  2,  3,  4,  1,  2,  3,    5,  1,  3,  3,  6,  7,  7,  1,
  /* 5x */    2,  3,  6,  3,  4,  1,  2,  8,    3,  9,  3, 12, 12, 12, 12, 12,
  /* 6x */   12,  1,  2,  3,  4,  1,  2,  3,    5,  1,  3,  3,  6,  7,  7,  1,
  /* 7x */    2,  3,  6,  3,  4,  1,  2,  8,    3,  9,  3, 12, 12, 12, 12, 12,

































};

/*
** Mapping from the character class number (0-12) to a symbol for each
** character class.  Note that initClass[] can be used to map the class
** symbol back into the class number.
*/
static const unsigned char className[] = ".ABCDHLMWY9 ?";

/*
** Generate a string of character classes corresponding to the


** ASCII characters in the input string zIn.  If the input is not


** ASCII then the behavior is undefined.



**
** Space to hold the result is obtained from sqlite3_malloc()
**
** Return NULL if memory allocation fails.  
*/
static unsigned char *characterClassString(const unsigned char *zIn, int nIn){
  unsigned char *zOut = sqlite3_malloc( nIn + 1 );
  int i;
  int nOut = 0;
  char cPrev = 0x77;

  const unsigned char *aClass = initClass;

  if( zOut==0 ) return 0;









  for(i=0; i<nIn; i++){
    unsigned char c = zIn[i];







    c = aClass[c&0x7f];

    if( c==CCLASS_OTHER && cPrev!=CCLASS_DIGIT ) continue;







    cPrev = c;
    if( c==CCLASS_SILENT ) continue;
    if( c==CCLASS_SPACE ) continue;
    aClass = midClass;
    c = className[c];
    if( c!=zOut[nOut-1] ) zOut[nOut++] = c;
  }
  zOut[nOut] = 0;
  return zOut;
}

/*
** This is an SQL function wrapper around characterClassString().  See
** the description of characterClassString() for additional information.
*/
static void characterClassSqlFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const unsigned char *zIn;
  unsigned char *zOut;

  zIn = sqlite3_value_text(argv[0]);
  if( zIn==0 ) return;
  zOut = characterClassString(zIn, sqlite3_value_bytes(argv[0]));
  if( zOut==0 ){
    sqlite3_result_error_nomem(context);
  }else{
    sqlite3_result_text(context, (char*)zOut, -1, sqlite3_free);
  }
}

/*
** Return the character class number for a character given its
** context.
*/
static char characterClass(char cPrev, char c){
  return cPrev==0 ? initClass[c&0x7f] : midClass[c&0x7f];
}

/*
** Return the cost of inserting or deleting character c immediately
** following character cPrev.  If cPrev==0, that means c is the first
** character of the word.
*/
static int insertOrDeleteCost(char cPrev, char c){
  char classC = characterClass(cPrev, c);
  char classCprev;

  if( classC==CCLASS_SILENT ){
    /* Insert or delete "silent" characters such as H or W */
    return 1;
  }
  if( cPrev==c ){
    /* Repeated characters, or miss a repeat */
    return 10;



  }
  classCprev = characterClass(cPrev, cPrev);
  if( classC==classCprev ){
    if( classC==CCLASS_VOWEL ){
      /* Remove or add a new vowel to a vowel cluster */
      return 15;
    }else{