# This is how we compile
#
TCCX = $(TCC) $(OPTS) $(THREADSAFE) $(USLEEP) -I. -I$(TOP)/src

# Object files for the SQLite library.
#
# LIBOBJ = btree.o hash.o os.o pager.o random.o \
#         util.o tclsqlite.o utf.o


LIBOBJ = attach.o auth.o btree.o build.o copy.o date.o delete.o \
         expr.o func.o hash.o insert.o \

         main.o opcodes.o os.o pager.o parse.o pragma.o printf.o random.o \
         select.o table.o tokenize.o trigger.o update.o util.o \
         vacuum.o vdbe.o vdbeaux.o where.o tclsqlite.o utf.o

# All of the source code files.
#
SRC = \
  $(TOP)/src/attach.c \
................................................................................
  $(TOP)/src/encode.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/insert.c \
  $(TOP)/src/main.c \
  $(TOP)/src/os.c \


  $(TOP)/src/pager.c \
  $(TOP)/src/pager.h \
  $(TOP)/src/parse.y \
  $(TOP)/src/pragma.c \
  $(TOP)/src/printf.c \
  $(TOP)/src/random.c \
  $(TOP)/src/select.c \
................................................................................
  $(TOP)/src/vdbe.h \
  $(TOP)/src/vdbeaux.c \
  $(TOP)/src/vdbeInt.h \
  $(TOP)/src/where.c

# Source code to the test files.
#
TESTSRC_SUBSET = \
   $(TOP)/src/os.c \
   $(TOP)/src/pager.c \
   $(TOP)/src/test1.c \
   $(TOP)/src/test2.c \
   $(TOP)/src/test3.c \
   $(TOP)/src/test5.c \
   $(TOP)/src/md5.c

TESTSRC = \
  $(TOP)/src/btree.c \
  $(TOP)/src/func.c \
  $(TOP)/src/os.c \


  $(TOP)/src/pager.c \
  $(TOP)/src/test1.c \
  $(TOP)/src/test2.c \
  $(TOP)/src/test3.c \
  $(TOP)/src/test4.c \
  $(TOP)/src/test5.c \
  $(TOP)/src/vdbe.c \
................................................................................
HDR = \
   sqlite.h  \
   $(TOP)/src/btree.h \
   config.h \
   $(TOP)/src/hash.h \
   opcodes.h \
   $(TOP)/src/os.h \



   $(TOP)/src/sqliteInt.h  \
   $(TOP)/src/vdbe.h \
   parse.h

# Header files used by the VDBE submodule
#
VDBEHDR = \
................................................................................
	cp parse.c opcodes.c tsrc

# Rules to build the LEMON compiler generator
#
lemon:	$(TOP)/tool/lemon.c $(TOP)/tool/lempar.c
	$(BCC) -o lemon $(TOP)/tool/lemon.c
	cp $(TOP)/tool/lempar.c .









btree.o:	$(TOP)/src/btree.c $(HDR) $(TOP)/src/pager.h
	$(TCCX) -c $(TOP)/src/btree.c

btree_rb.o:	$(TOP)/src/btree_rb.c $(HDR)
	$(TCCX) -c $(TOP)/src/btree_rb.c

build.o:	$(TOP)/src/build.c $(HDR)
	$(TCCX) -c $(TOP)/src/build.c

main.o:	$(TOP)/src/main.c $(HDR)
	$(TCCX) -c $(TOP)/src/main.c

pager.o:	$(TOP)/src/pager.c $(HDR) $(TOP)/src/pager.h
	$(TCCX) -c $(TOP)/src/pager.c

opcodes.o:	opcodes.c
	$(TCCX) -c opcodes.c

opcodes.c:	$(TOP)/src/vdbe.c
	echo '/* Automatically generated file.  Do not edit */' >opcodes.c
	echo 'char *sqlite3OpcodeNames[] = { "???", ' >>opcodes.c
	grep '^case OP_' $(TOP)/src/vdbe.c | \
	  sed -e 's/^.*OP_/  "/' -e 's/:.*$$/", /' >>opcodes.c
	echo '};' >>opcodes.c

opcodes.h:	$(TOP)/src/vdbe.h
	echo '/* Automatically generated file.  Do not edit */' >opcodes.h
	grep '^case OP_' $(TOP)/src/vdbe.c | \
	  sed -e 's/://' | \
	  awk '{printf "#define %-30s %3d\n", $$2, ++cnt}' >>opcodes.h

os.o:	$(TOP)/src/os.c $(HDR)
	$(TCCX) -c $(TOP)/src/os.c

parse.o:	parse.c $(HDR)
	$(TCCX) -c parse.c

parse.h:	parse.c

parse.c:	$(TOP)/src/parse.y lemon
	cp $(TOP)/src/parse.y .
	./lemon parse.y

# The config.h file will contain a single #define that tells us how
# many bytes are in a pointer.  This only works if a pointer is the
# same size on the host as it is on the target.  If you are cross-compiling
# to a target with a different pointer size, you'll need to manually
# configure the config.h file.
#
config.h:	
................................................................................
	echo '"#define SQLITE_PTR_SZ %d",sizeof(char*));' >>temp.c
	echo 'exit(0);}' >>temp.c
	$(BCC) -o temp temp.c
	./temp >config.h
	echo >>config.h
	rm -f temp.c temp

sqlite.h:	$(TOP)/src/sqlite.h.in 
	sed -e s/--VERS--/`cat ${TOP}/VERSION`/ \
            -e s/--ENCODING--/$(ENCODING)/ \
                 $(TOP)/src/sqlite.h.in >sqlite.h

tokenize.o:	$(TOP)/src/tokenize.c $(HDR)
	$(TCCX) -c $(TOP)/src/tokenize.c

trigger.o:	$(TOP)/src/trigger.c $(HDR)
	$(TCCX) -c $(TOP)/src/trigger.c

utf.o:	$(TOP)/src/utf.c $(HDR)
	$(TCCX) -c $(TOP)/src/utf.c

util.o:	$(TOP)/src/util.c $(HDR)
	$(TCCX) -c $(TOP)/src/util.c

vacuum.o:	$(TOP)/src/vacuum.c $(HDR)
	$(TCCX) -c $(TOP)/src/vacuum.c

vdbe.o:	$(TOP)/src/vdbe.c $(VDBEHDR)
	$(TCCX) -c $(TOP)/src/vdbe.c

vdbeaux.o:	$(TOP)/src/vdbeaux.c $(VDBEHDR)
	$(TCCX) -c $(TOP)/src/vdbeaux.c

where.o:	$(TOP)/src/where.c $(HDR)
	$(TCCX) -c $(TOP)/src/where.c

copy.o:	$(TOP)/src/copy.c $(HDR)
	$(TCCX) -c $(TOP)/src/copy.c

date.o:	$(TOP)/src/date.c $(HDR)
	$(TCCX) -c $(TOP)/src/date.c

delete.o:	$(TOP)/src/delete.c $(HDR)
................................................................................

hash.o:	$(TOP)/src/hash.c $(HDR)
	$(TCCX) -c $(TOP)/src/hash.c

insert.o:	$(TOP)/src/insert.c $(HDR)
	$(TCCX) -c $(TOP)/src/insert.c
















































random.o:	$(TOP)/src/random.c $(HDR)
	$(TCCX) -c $(TOP)/src/random.c

select.o:	$(TOP)/src/select.c $(HDR)
	$(TCCX) -c $(TOP)/src/select.c






table.o:	$(TOP)/src/table.c $(HDR)
	$(TCCX) -c $(TOP)/src/table.c










update.o:	$(TOP)/src/update.c $(HDR)
	$(TCCX) -c $(TOP)/src/update.c

tclsqlite.o:	$(TOP)/src/tclsqlite.c $(HDR)
	$(TCCX) $(TCL_FLAGS) -c $(TOP)/src/tclsqlite.c

pragma.o:	$(TOP)/src/pragma.c $(HDR)
	$(TCCX) $(TCL_FLAGS) -c $(TOP)/src/pragma.c

printf.o:	$(TOP)/src/printf.c $(HDR)
	$(TCCX) $(TCL_FLAGS) -c $(TOP)/src/printf.c

attach.o:	$(TOP)/src/attach.c $(HDR)
	$(TCCX) -c $(TOP)/src/attach.c




auth.o:	$(TOP)/src/auth.c $(HDR)
	$(TCCX) -c $(TOP)/src/auth.c



tclsqlite:	$(TOP)/src/tclsqlite.c libsqlite.a
	$(TCCX) $(TCL_FLAGS) -DTCLSH=1 -o tclsqlite \
		$(TOP)/src/tclsqlite.c libsqlite.a $(LIBTCL)

testfixture$(EXE):	$(TOP)/src/tclsqlite.c libsqlite.a $(TESTSRC)
	$(TCCX) $(TCL_FLAGS) -DTCLSH=1 -DSQLITE_TEST=1 -o testfixture$(EXE) \
		$(TESTSRC) $(TOP)/src/tclsqlite.c \
................................................................................

fulltest:	testfixture$(EXE) sqlite$(EXE)
	./testfixture$(EXE) $(TOP)/test/all.test

test:	testfixture$(EXE) sqlite$(EXE)
	./testfixture$(EXE) $(TOP)/test/quick.test



index.html:	$(TOP)/www/index.tcl last_change
	tclsh $(TOP)/www/index.tcl `cat $(TOP)/VERSION` >index.html

sqlite.html:	$(TOP)/www/sqlite.tcl
	tclsh $(TOP)/www/sqlite.tcl >sqlite.html

c_interface.html:	$(TOP)/www/c_interface.tcl
	tclsh $(TOP)/www/c_interface.tcl >c_interface.html

changes.html:	$(TOP)/www/changes.tcl
	tclsh $(TOP)/www/changes.tcl >changes.html

lang.html:	$(TOP)/www/lang.tcl
	tclsh $(TOP)/www/lang.tcl >lang.html







vdbe.html:	$(TOP)/www/vdbe.tcl
	tclsh $(TOP)/www/vdbe.tcl >vdbe.html










arch.html:	$(TOP)/www/arch.tcl
	tclsh $(TOP)/www/arch.tcl >arch.html

arch.png:	$(TOP)/www/arch.png
	cp $(TOP)/www/arch.png .

opcode.html:	$(TOP)/www/opcode.tcl $(TOP)/src/vdbe.c
	tclsh $(TOP)/www/opcode.tcl $(TOP)/src/vdbe.c >opcode.html

mingw.html:	$(TOP)/www/mingw.tcl
	tclsh $(TOP)/www/mingw.tcl >mingw.html

tclsqlite.html:	$(TOP)/www/tclsqlite.tcl
	tclsh $(TOP)/www/tclsqlite.tcl >tclsqlite.html




speed.html:	$(TOP)/www/speed.tcl
	tclsh $(TOP)/www/speed.tcl >speed.html

faq.html:	$(TOP)/www/faq.tcl
	tclsh $(TOP)/www/faq.tcl >faq.html

formatchng.html:	$(TOP)/www/formatchng.tcl
	tclsh $(TOP)/www/formatchng.tcl >formatchng.html

conflict.html:	$(TOP)/www/conflict.tcl
	tclsh $(TOP)/www/conflict.tcl >conflict.html

download.html:	$(TOP)/www/download.tcl
	tclsh $(TOP)/www/download.tcl >download.html

omitted.html:	$(TOP)/www/omitted.tcl
	tclsh $(TOP)/www/omitted.tcl >omitted.html

datatypes.html:	$(TOP)/www/datatypes.tcl
	tclsh $(TOP)/www/datatypes.tcl >datatypes.html

quickstart.html:	$(TOP)/www/quickstart.tcl
	tclsh $(TOP)/www/quickstart.tcl >quickstart.html

fileformat.html:	$(TOP)/www/fileformat.tcl
	tclsh $(TOP)/www/fileformat.tcl >fileformat.html

nulls.html:	$(TOP)/www/nulls.tcl
	tclsh $(TOP)/www/nulls.tcl >nulls.html


# Files to be published on the website.
#
DOC = \
  index.html \
  sqlite.html \
  changes.html \
  lang.html \
  opcode.html \
  arch.html \
  arch.png \
  vdbe.html \
  c_interface.html \
  mingw.html \
  tclsqlite.html \
  download.html \
  speed.html \
  faq.html \
  formatchng.html \
  conflict.html \



  omitted.html \
  datatypes.html \
  quickstart.html \
  fileformat.html \


  nulls.html

doc:	$(DOC)
	mkdir -p doc
	mv $(DOC) doc



install:	sqlite libsqlite.a sqlite.h
	mv sqlite /usr/bin
	mv libsqlite.a /usr/lib
	mv sqlite.h /usr/include

clean:	
	rm -f *.o sqlite libsqlite.a sqlite.h opcodes.*
	rm -f lemon lempar.c parse.* sqlite*.tar.gz
	rm -f $(PUBLISH)
	rm -f *.da *.bb *.bbg gmon.out
	rm -rf tsrc

# This is how we compile
#
TCCX = $(TCC) $(OPTS) $(THREADSAFE) $(USLEEP) -I. -I$(TOP)/src

# Object files for the SQLite library.
#




LIBOBJ = attach.o auth.o btree.o build.o copy.o date.o delete.o \
         expr.o func.o hash.o insert.o \
         main.o opcodes.o os_mac.o os_unix.o os_win.o \
         pager.o parse.o pragma.o printf.o random.o \
         select.o table.o tokenize.o trigger.o update.o util.o \
         vacuum.o vdbe.o vdbeaux.o where.o tclsqlite.o utf.o

# All of the source code files.
#
SRC = \
  $(TOP)/src/attach.c \
................................................................................
  $(TOP)/src/encode.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/insert.c \
  $(TOP)/src/main.c \
  $(TOP)/src/os_mac.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/pragma.c \
  $(TOP)/src/printf.c \
  $(TOP)/src/random.c \
  $(TOP)/src/select.c \
................................................................................
  $(TOP)/src/vdbe.h \
  $(TOP)/src/vdbeaux.c \
  $(TOP)/src/vdbeInt.h \
  $(TOP)/src/where.c

# Source code to the test files.
#









TESTSRC = \
  $(TOP)/src/btree.c \
  $(TOP)/src/func.c \
  $(TOP)/src/os_mac.c \
  $(TOP)/src/os_unix.c \
  $(TOP)/src/os_win.c \
  $(TOP)/src/pager.c \
  $(TOP)/src/test1.c \
  $(TOP)/src/test2.c \
  $(TOP)/src/test3.c \
  $(TOP)/src/test4.c \
  $(TOP)/src/test5.c \
  $(TOP)/src/vdbe.c \
................................................................................
HDR = \
   sqlite.h  \
   $(TOP)/src/btree.h \
   config.h \
   $(TOP)/src/hash.h \
   opcodes.h \
   $(TOP)/src/os.h \
   $(TOP)/src/os_mac.h \
   $(TOP)/src/os_unix.h \
   $(TOP)/src/os_win.h \
   $(TOP)/src/sqliteInt.h  \
   $(TOP)/src/vdbe.h \
   parse.h

# Header files used by the VDBE submodule
#
VDBEHDR = \
................................................................................
	cp parse.c opcodes.c tsrc

# Rules to build the LEMON compiler generator
#
lemon:	$(TOP)/tool/lemon.c $(TOP)/tool/lempar.c
	$(BCC) -o lemon $(TOP)/tool/lemon.c
	cp $(TOP)/tool/lempar.c .

# Rules to build individual files
#
attach.o:	$(TOP)/src/attach.c $(HDR)
	$(TCCX) -c $(TOP)/src/attach.c

auth.o:	$(TOP)/src/auth.c $(HDR)
	$(TCCX) -c $(TOP)/src/auth.c

btree.o:	$(TOP)/src/btree.c $(HDR) $(TOP)/src/pager.h
	$(TCCX) -c $(TOP)/src/btree.c




build.o:	$(TOP)/src/build.c $(HDR)
	$(TCCX) -c $(TOP)/src/build.c



































# The config.h file will contain a single #define that tells us how
# many bytes are in a pointer.  This only works if a pointer is the
# same size on the host as it is on the target.  If you are cross-compiling
# to a target with a different pointer size, you'll need to manually
# configure the config.h file.
#
config.h:	
................................................................................
	echo '"#define SQLITE_PTR_SZ %d",sizeof(char*));' >>temp.c
	echo 'exit(0);}' >>temp.c
	$(BCC) -o temp temp.c
	./temp >config.h
	echo >>config.h
	rm -f temp.c temp






























copy.o:	$(TOP)/src/copy.c $(HDR)
	$(TCCX) -c $(TOP)/src/copy.c

date.o:	$(TOP)/src/date.c $(HDR)
	$(TCCX) -c $(TOP)/src/date.c

delete.o:	$(TOP)/src/delete.c $(HDR)
................................................................................

hash.o:	$(TOP)/src/hash.c $(HDR)
	$(TCCX) -c $(TOP)/src/hash.c

insert.o:	$(TOP)/src/insert.c $(HDR)
	$(TCCX) -c $(TOP)/src/insert.c


main.o:	$(TOP)/src/main.c $(HDR)
	$(TCCX) -c $(TOP)/src/main.c

pager.o:	$(TOP)/src/pager.c $(HDR) $(TOP)/src/pager.h
	$(TCCX) -c $(TOP)/src/pager.c

opcodes.o:	opcodes.c
	$(TCCX) -c opcodes.c

opcodes.c:	$(TOP)/src/vdbe.c
	echo '/* Automatically generated file.  Do not edit */' >opcodes.c
	echo 'char *sqlite3OpcodeNames[] = { "???", ' >>opcodes.c
	grep '^case OP_' $(TOP)/src/vdbe.c | \
	  sed -e 's/^.*OP_/  "/' -e 's/:.*$$/", /' >>opcodes.c
	echo '};' >>opcodes.c

opcodes.h:	$(TOP)/src/vdbe.h
	echo '/* Automatically generated file.  Do not edit */' >opcodes.h
	grep '^case OP_' $(TOP)/src/vdbe.c | \
	  sed -e 's/://' | \
	  awk '{printf "#define %-30s %3d\n", $$2, ++cnt}' >>opcodes.h

os_mac.o:	$(TOP)/src/os_mac.c $(HDR)
	$(TCCX) -c $(TOP)/src/os_mac.c

os_unix.o:	$(TOP)/src/os_unix.c $(HDR)
	$(TCCX) -c $(TOP)/src/os_unix.c

os_win.o:	$(TOP)/src/os_win.c $(HDR)
	$(TCCX) -c $(TOP)/src/os_win.c

parse.o:	parse.c $(HDR)
	$(TCCX) -c parse.c

parse.h:	parse.c

parse.c:	$(TOP)/src/parse.y lemon
	cp $(TOP)/src/parse.y .
	./lemon parse.y

pragma.o:	$(TOP)/src/pragma.c $(HDR)
	$(TCCX) $(TCL_FLAGS) -c $(TOP)/src/pragma.c

printf.o:	$(TOP)/src/printf.c $(HDR)
	$(TCCX) $(TCL_FLAGS) -c $(TOP)/src/printf.c

random.o:	$(TOP)/src/random.c $(HDR)
	$(TCCX) -c $(TOP)/src/random.c

select.o:	$(TOP)/src/select.c $(HDR)
	$(TCCX) -c $(TOP)/src/select.c

sqlite.h:	$(TOP)/src/sqlite.h.in 
	sed -e s/--VERS--/`cat ${TOP}/VERSION`/ \
            -e s/--ENCODING--/$(ENCODING)/ \
                 $(TOP)/src/sqlite.h.in >sqlite.h

table.o:	$(TOP)/src/table.c $(HDR)
	$(TCCX) -c $(TOP)/src/table.c

tclsqlite.o:	$(TOP)/src/tclsqlite.c $(HDR)
	$(TCCX) $(TCL_FLAGS) -c $(TOP)/src/tclsqlite.c

tokenize.o:	$(TOP)/src/tokenize.c $(HDR)
	$(TCCX) -c $(TOP)/src/tokenize.c

trigger.o:	$(TOP)/src/trigger.c $(HDR)
	$(TCCX) -c $(TOP)/src/trigger.c

update.o:	$(TOP)/src/update.c $(HDR)
	$(TCCX) -c $(TOP)/src/update.c

utf.o:	$(TOP)/src/utf.c $(HDR)
	$(TCCX) -c $(TOP)/src/utf.c

util.o:	$(TOP)/src/util.c $(HDR)
	$(TCCX) -c $(TOP)/src/util.c

vacuum.o:	$(TOP)/src/vacuum.c $(HDR)
	$(TCCX) -c $(TOP)/src/vacuum.c

vdbe.o:	$(TOP)/src/vdbe.c $(VDBEHDR)
	$(TCCX) -c $(TOP)/src/vdbe.c

vdbeaux.o:	$(TOP)/src/vdbeaux.c $(VDBEHDR)
	$(TCCX) -c $(TOP)/src/vdbeaux.c

where.o:	$(TOP)/src/where.c $(HDR)
	$(TCCX) -c $(TOP)/src/where.c

# Rules for building test programs and for running tests
#
tclsqlite:	$(TOP)/src/tclsqlite.c libsqlite.a
	$(TCCX) $(TCL_FLAGS) -DTCLSH=1 -o tclsqlite \
		$(TOP)/src/tclsqlite.c libsqlite.a $(LIBTCL)

testfixture$(EXE):	$(TOP)/src/tclsqlite.c libsqlite.a $(TESTSRC)
	$(TCCX) $(TCL_FLAGS) -DTCLSH=1 -DSQLITE_TEST=1 -o testfixture$(EXE) \
		$(TESTSRC) $(TOP)/src/tclsqlite.c \
................................................................................

fulltest:	testfixture$(EXE) sqlite$(EXE)
	./testfixture$(EXE) $(TOP)/test/all.test

test:	testfixture$(EXE) sqlite$(EXE)
	./testfixture$(EXE) $(TOP)/test/quick.test

# Rules used to build documentation
#
arch.html:	$(TOP)/www/arch.tcl
	tclsh $(TOP)/www/arch.tcl >arch.html

arch.png:	$(TOP)/www/arch.png
	cp $(TOP)/www/arch.png .

c_interface.html:	$(TOP)/www/c_interface.tcl
	tclsh $(TOP)/www/c_interface.tcl >c_interface.html

changes.html:	$(TOP)/www/changes.tcl
	tclsh $(TOP)/www/changes.tcl >changes.html

conflict.html:	$(TOP)/www/conflict.tcl
	tclsh $(TOP)/www/conflict.tcl >conflict.html

datatypes.html:	$(TOP)/www/datatypes.tcl
	tclsh $(TOP)/www/datatypes.tcl >datatypes.html

download.html:	$(TOP)/www/download.tcl
	tclsh $(TOP)/www/download.tcl >download.html

faq.html:	$(TOP)/www/faq.tcl
	tclsh $(TOP)/www/faq.tcl >faq.html

fileformat.html:	$(TOP)/www/fileformat.tcl
	tclsh $(TOP)/www/fileformat.tcl >fileformat.html

formatchng.html:	$(TOP)/www/formatchng.tcl
	tclsh $(TOP)/www/formatchng.tcl >formatchng.html

index.html:	$(TOP)/www/index.tcl last_change
	tclsh $(TOP)/www/index.tcl `cat $(TOP)/VERSION` >index.html

lang.html:	$(TOP)/www/lang.tcl
	tclsh $(TOP)/www/lang.tcl >lang.html

omitted.html:	$(TOP)/www/omitted.tcl
	tclsh $(TOP)/www/omitted.tcl >omitted.html

opcode.html:	$(TOP)/www/opcode.tcl $(TOP)/src/vdbe.c
	tclsh $(TOP)/www/opcode.tcl $(TOP)/src/vdbe.c >opcode.html

mingw.html:	$(TOP)/www/mingw.tcl
	tclsh $(TOP)/www/mingw.tcl >mingw.html

nulls.html:	$(TOP)/www/nulls.tcl
	tclsh $(TOP)/www/nulls.tcl >nulls.html

quickstart.html:	$(TOP)/www/quickstart.tcl
	tclsh $(TOP)/www/quickstart.tcl >quickstart.html

speed.html:	$(TOP)/www/speed.tcl
	tclsh $(TOP)/www/speed.tcl >speed.html

sqlite.html:	$(TOP)/www/sqlite.tcl
	tclsh $(TOP)/www/sqlite.tcl >sqlite.html










tclsqlite.html:	$(TOP)/www/tclsqlite.tcl
	tclsh $(TOP)/www/tclsqlite.tcl >tclsqlite.html










vdbe.html:	$(TOP)/www/vdbe.tcl
	tclsh $(TOP)/www/vdbe.tcl >vdbe.html


# Files to be published on the website.
#
DOC = \





  arch.html \
  arch.png \
  changes.html \
  c_interface.html \
  conflict.html \
  datatypes.html \
  download.html \
  faq.html \
  fileformat.html \
  formatchng.html \
  index.html \
  lang.html \
  mingw.html \
  nulls.html \
  omitted.html \
  opcode.html \
  quickstart.html \
  speed.html \
  sqlite.html \
  tclsqlite.html \
  vdbe.html 

doc:	$(DOC)
	mkdir -p doc
	mv $(DOC) doc

# Standard install and cleanup targets
#
install:	sqlite libsqlite.a sqlite.h
	mv sqlite /usr/bin
	mv libsqlite.a /usr/lib
	mv sqlite.h /usr/include

clean:	
	rm -f *.o sqlite libsqlite.a sqlite.h opcodes.*
	rm -f lemon lempar.c parse.* sqlite*.tar.gz
	rm -f $(PUBLISH)
	rm -f *.da *.bb *.bbg gmon.out
	rm -rf tsrc

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.184 2004/05/22 09:21:21 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** A pointer to this structure is used to communicate information
................................................................................
** from sqlite3Init into the sqlite3InitCallback.
*/
typedef struct {
  sqlite *db;         /* The database being initialized */
  char **pzErrMsg;    /* Error message stored here */
} InitData;







/*
** Fill the InitData structure with an error message that indicates
** that the database is corrupt.
*/
static void corruptSchema(InitData *pData, const char *zExtra){
  sqlite3SetString(pData->pzErrMsg, "malformed database schema",
     zExtra!=0 && zExtra[0]!=0 ? " - " : (char*)0, zExtra, (char*)0);
................................................................................
** sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16().
*/
int sqlite3_reset_new(sqlite3_stmt *pStmt){
  int rc = sqlite3VdbeReset((Vdbe*)pStmt, 0);
  sqlite3VdbeMakeReady((Vdbe*)pStmt, -1, 0);
  return rc;
}

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.185 2004/05/22 17:41:59 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** A pointer to this structure is used to communicate information
................................................................................
** from sqlite3Init into the sqlite3InitCallback.
*/
typedef struct {
  sqlite *db;         /* The database being initialized */
  char **pzErrMsg;    /* Error message stored here */
} InitData;

/*
** The following constant value is used by the SQLITE3_BIGENDIAN and
** SQLITE3_LITTLEENDIAN macros.
*/
const int sqlite3one = 1;

/*
** Fill the InitData structure with an error message that indicates
** that the database is corrupt.
*/
static void corruptSchema(InitData *pData, const char *zExtra){
  sqlite3SetString(pData->pzErrMsg, "malformed database schema",
     zExtra!=0 && zExtra[0]!=0 ? " - " : (char*)0, zExtra, (char*)0);
................................................................................
** sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16().
*/
int sqlite3_reset_new(sqlite3_stmt *pStmt){
  int rc = sqlite3VdbeReset((Vdbe*)pStmt, 0);
  sqlite3VdbeMakeReady((Vdbe*)pStmt, -1, 0);
  return rc;
}

/*
** 2001 September 16
**
** 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 particular operating
** systems.  The purpose of this file is to provide a uniform abstraction
** on which the rest of SQLite can operate.
*/
#include "os.h"          /* Must be first to enable large file support */
#include "sqliteInt.h"

#if OS_UNIX
# include <time.h>
# include <errno.h>
# include <unistd.h>
# ifndef O_LARGEFILE
#  define O_LARGEFILE 0
# endif
# ifdef SQLITE_DISABLE_LFS
#  undef O_LARGEFILE
#  define O_LARGEFILE 0
# endif
# ifndef O_NOFOLLOW
#  define O_NOFOLLOW 0
# endif
# ifndef O_BINARY
#  define O_BINARY 0
# endif
#endif


#if OS_WIN
# include <winbase.h>
#endif

#if OS_MAC
# include <extras.h>
# include <path2fss.h>
# include <TextUtils.h>
# include <FinderRegistry.h>
# include <Folders.h>
# include <Timer.h>
# include <OSUtils.h>
#endif

/*
** The DJGPP compiler environment looks mostly like Unix, but it
** lacks the fcntl() system call.  So redefine fcntl() to be something
** that always succeeds.  This means that locking does not occur under
** DJGPP.  But its DOS - what did you expect?
*/
#ifdef __DJGPP__
# define fcntl(A,B,C) 0
#endif

/*
** Macros used to determine whether or not to use threads.  The
** SQLITE_UNIX_THREADS macro is defined if we are synchronizing for
** Posix threads and SQLITE_W32_THREADS is defined if we are
** synchronizing using Win32 threads.
*/
#if OS_UNIX && defined(THREADSAFE) && THREADSAFE
# include <pthread.h>
# define SQLITE_UNIX_THREADS 1
#endif
#if OS_WIN && defined(THREADSAFE) && THREADSAFE
# define SQLITE_W32_THREADS 1
#endif
#if OS_MAC && defined(THREADSAFE) && THREADSAFE
# include <Multiprocessing.h>
# define SQLITE_MACOS_MULTITASKING 1
#endif

/*
** Macros for performance tracing.  Normally turned off
*/
#if 0
static int last_page = 0;
__inline__ unsigned long long int hwtime(void){
  unsigned long long int x;
  __asm__("rdtsc\n\t"
          "mov %%edx, %%ecx\n\t"
          :"=A" (x));
  return x;
}
static unsigned long long int g_start;
static unsigned int elapse;
#define TIMER_START       g_start=hwtime()
#define TIMER_END         elapse=hwtime()-g_start
#define SEEK(X)           last_page=(X)
#define TRACE1(X)         fprintf(stderr,X)
#define TRACE2(X,Y)       fprintf(stderr,X,Y)
#define TRACE3(X,Y,Z)     fprintf(stderr,X,Y,Z)
#define TRACE4(X,Y,Z,A)   fprintf(stderr,X,Y,Z,A)
#define TRACE5(X,Y,Z,A,B) fprintf(stderr,X,Y,Z,A,B)
#else
#define TIMER_START
#define TIMER_END
#define SEEK(X)
#define TRACE1(X)
#define TRACE2(X,Y)
#define TRACE3(X,Y,Z)
#define TRACE4(X,Y,Z,A)
#define TRACE5(X,Y,Z,A,B)
#endif


#if OS_UNIX
/*
** Here is the dirt on POSIX advisory locks:  ANSI STD 1003.1 (1996)
** section 6.5.2.2 lines 483 through 490 specify that when a process
** sets or clears a lock, that operation overrides any prior locks set
** by the same process.  It does not explicitly say so, but this implies
** that it overrides locks set by the same process using a different
** file descriptor.  Consider this test case:
**
**       int fd1 = open("./file1", O_RDWR|O_CREAT, 0644);
**       int fd2 = open("./file2", O_RDWR|O_CREAT, 0644);
**
** Suppose ./file1 and ./file2 are really the same file (because
** one is a hard or symbolic link to the other) then if you set
** an exclusive lock on fd1, then try to get an exclusive lock
** on fd2, it works.  I would have expected the second lock to
** fail since there was already a lock on the file due to fd1.
** But not so.  Since both locks came from the same process, the
** second overrides the first, even though they were on different
** file descriptors opened on different file names.
**
** Bummer.  If you ask me, this is broken.  Badly broken.  It means
** that we cannot use POSIX locks to synchronize file access among
** competing threads of the same process.  POSIX locks will work fine
** to synchronize access for threads in separate processes, but not
** threads within the same process.
**
** To work around the problem, SQLite has to manage file locks internally
** on its own.  Whenever a new database is opened, we have to find the
** specific inode of the database file (the inode is determined by the
** st_dev and st_ino fields of the stat structure that fstat() fills in)
** and check for locks already existing on that inode.  When locks are
** created or removed, we have to look at our own internal record of the
** locks to see if another thread has previously set a lock on that same
** inode.
**
** The OsFile structure for POSIX is no longer just an integer file
** descriptor.  It is now a structure that holds the integer file
** descriptor and a pointer to a structure that describes the internal
** locks on the corresponding inode.  There is one locking structure
** per inode, so if the same inode is opened twice, both OsFile structures
** point to the same locking structure.  The locking structure keeps
** a reference count (so we will know when to delete it) and a "cnt"
** field that tells us its internal lock status.  cnt==0 means the
** file is unlocked.  cnt==-1 means the file has an exclusive lock.
** cnt>0 means there are cnt shared locks on the file.
**
** Any attempt to lock or unlock a file first checks the locking
** structure.  The fcntl() system call is only invoked to set a 
** POSIX lock if the internal lock structure transitions between
** a locked and an unlocked state.
**
** 2004-Jan-11:
** More recent discoveries about POSIX advisory locks.  (The more
** I discover, the more I realize the a POSIX advisory locks are
** an abomination.)
**
** If you close a file descriptor that points to a file that has locks,
** all locks on that file that are owned by the current process are
** released.  To work around this problem, each OsFile structure contains
** a pointer to an openCnt structure.  There is one openCnt structure
** per open inode, which means that multiple OsFiles can point to a single
** openCnt.  When an attempt is made to close an OsFile, if there are
** other OsFiles open on the same inode that are holding locks, the call
** to close() the file descriptor is deferred until all of the locks clear.
** The openCnt structure keeps a list of file descriptors that need to
** be closed and that list is walked (and cleared) when the last lock
** clears.
**
** First, under Linux threads, because each thread has a separate
** process ID, lock operations in one thread do not override locks
** to the same file in other threads.  Linux threads behave like
** separate processes in this respect.  But, if you close a file
** descriptor in linux threads, all locks are cleared, even locks
** on other threads and even though the other threads have different
** process IDs.  Linux threads is inconsistent in this respect.
** (I'm beginning to think that linux threads is an abomination too.)
** The consequence of this all is that the hash table for the lockInfo
** structure has to include the process id as part of its key because
** locks in different threads are treated as distinct.  But the 
** openCnt structure should not include the process id in its
** key because close() clears lock on all threads, not just the current
** thread.  Were it not for this goofiness in linux threads, we could
** combine the lockInfo and openCnt structures into a single structure.
*/

/*
** An instance of the following structure serves as the key used
** to locate a particular lockInfo structure given its inode.  Note
** that we have to include the process ID as part of the key.  On some
** threading implementations (ex: linux), each thread has a separate
** process ID.
*/
struct lockKey {
  dev_t dev;   /* Device number */
  ino_t ino;   /* Inode number */
  pid_t pid;   /* Process ID */
};

/*
** An instance of the following structure is allocated for each open
** inode on each thread with a different process ID.  (Threads have
** different process IDs on linux, but not on most other unixes.)
**
** A single inode can have multiple file descriptors, so each OsFile
** structure contains a pointer to an instance of this object and this
** object keeps a count of the number of OsFiles pointing to it.
*/
struct lockInfo {
  struct lockKey key;  /* The lookup key */
  int cnt;             /* 0: unlocked.  -1: write lock.  1...: read lock. */
  int nRef;            /* Number of pointers to this structure */
};

/*
** An instance of the following structure serves as the key used
** to locate a particular openCnt structure given its inode.  This
** is the same as the lockKey except that the process ID is omitted.
*/
struct openKey {
  dev_t dev;   /* Device number */
  ino_t ino;   /* Inode number */
};

/*
** An instance of the following structure is allocated for each open
** inode.  This structure keeps track of the number of locks on that
** inode.  If a close is attempted against an inode that is holding
** locks, the close is deferred until all locks clear by adding the
** file descriptor to be closed to the pending list.
*/
struct openCnt {
  struct openKey key;   /* The lookup key */
  int nRef;             /* Number of pointers to this structure */
  int nLock;            /* Number of outstanding locks */
  int nPending;         /* Number of pending close() operations */
  int *aPending;        /* Malloced space holding fd's awaiting a close() */
};

/* 
** These hash table maps inodes and process IDs into lockInfo and openCnt
** structures.  Access to these hash tables must be protected by a mutex.
*/
static Hash lockHash = { SQLITE_HASH_BINARY, 0, 0, 0, 0, 0 };
static Hash openHash = { SQLITE_HASH_BINARY, 0, 0, 0, 0, 0 };

/*
** Release a lockInfo structure previously allocated by findLockInfo().
*/
static void releaseLockInfo(struct lockInfo *pLock){
  pLock->nRef--;
  if( pLock->nRef==0 ){
    sqlite3HashInsert(&lockHash, &pLock->key, sizeof(pLock->key), 0);
    sqliteFree(pLock);
  }
}

/*
** Release a openCnt structure previously allocated by findLockInfo().
*/
static void releaseOpenCnt(struct openCnt *pOpen){
  pOpen->nRef--;
  if( pOpen->nRef==0 ){
    sqlite3HashInsert(&openHash, &pOpen->key, sizeof(pOpen->key), 0);
    sqliteFree(pOpen->aPending);
    sqliteFree(pOpen);
  }
}

/*
** Given a file descriptor, locate lockInfo and openCnt structures that
** describes that file descriptor.  Create a new ones if necessary.  The
** return values might be unset if an error occurs.
**
** Return the number of errors.
*/
int findLockInfo(
  int fd,                      /* The file descriptor used in the key */
  struct lockInfo **ppLock,    /* Return the lockInfo structure here */
  struct openCnt **ppOpen   /* Return the openCnt structure here */
){
  int rc;
  struct lockKey key1;
  struct openKey key2;
  struct stat statbuf;
  struct lockInfo *pLock;
  struct openCnt *pOpen;
  rc = fstat(fd, &statbuf);
  if( rc!=0 ) return 1;
  memset(&key1, 0, sizeof(key1));
  key1.dev = statbuf.st_dev;
  key1.ino = statbuf.st_ino;
  key1.pid = getpid();
  memset(&key2, 0, sizeof(key2));
  key2.dev = statbuf.st_dev;
  key2.ino = statbuf.st_ino;
  pLock = (struct lockInfo*)sqlite3HashFind(&lockHash, &key1, sizeof(key1));
  if( pLock==0 ){
    struct lockInfo *pOld;
    pLock = sqliteMallocRaw( sizeof(*pLock) );
    if( pLock==0 ) return 1;
    pLock->key = key1;
    pLock->nRef = 1;
    pLock->cnt = 0;
    pOld = sqlite3HashInsert(&lockHash, &pLock->key, sizeof(key1), pLock);
    if( pOld!=0 ){
      assert( pOld==pLock );
      sqliteFree(pLock);
      return 1;
    }
  }else{
    pLock->nRef++;
  }
  *ppLock = pLock;
  pOpen = (struct openCnt*)sqlite3HashFind(&openHash, &key2, sizeof(key2));
  if( pOpen==0 ){
    struct openCnt *pOld;
    pOpen = sqliteMallocRaw( sizeof(*pOpen) );
    if( pOpen==0 ){
      releaseLockInfo(pLock);
      return 1;
    }
    pOpen->key = key2;
    pOpen->nRef = 1;
    pOpen->nLock = 0;
    pOpen->nPending = 0;
    pOpen->aPending = 0;
    pOld = sqlite3HashInsert(&openHash, &pOpen->key, sizeof(key2), pOpen);
    if( pOld!=0 ){
      assert( pOld==pOpen );
      sqliteFree(pOpen);
      releaseLockInfo(pLock);
      return 1;
    }
  }else{
    pOpen->nRef++;
  }
  *ppOpen = pOpen;
  return 0;
}

#endif  /** POSIX advisory lock work-around **/

/*
** If we compile with the SQLITE_TEST macro set, then the following block
** of code will give us the ability to simulate a disk I/O error.  This
** is used for testing the I/O recovery logic.
*/
#ifdef SQLITE_TEST
int sqlite3_io_error_pending = 0;
#define SimulateIOError(A)  \
   if( sqlite3_io_error_pending ) \
     if( sqlite3_io_error_pending-- == 1 ){ local_ioerr(); return A; }
static void local_ioerr(){
  sqlite3_io_error_pending = 0;  /* Really just a place to set a breakpoint */
}
#else
#define SimulateIOError(A)
#endif

/*
** When testing, keep a count of the number of open files.
*/
#ifdef SQLITE_TEST
int sqlite3_open_file_count = 0;
#define OpenCounter(X)  sqlite3_open_file_count+=(X)
#else
#define OpenCounter(X)
#endif


/*
** Delete the named file
*/
int sqlite3OsDelete(const char *zFilename){
#if OS_UNIX
  unlink(zFilename);
#endif
#if OS_WIN
  DeleteFile(zFilename);
#endif
#if OS_MAC
  unlink(zFilename);
#endif
  return SQLITE_OK;
}

/*
** Return TRUE if the named file exists.
*/
int sqlite3OsFileExists(const char *zFilename){
#if OS_UNIX
  return access(zFilename, 0)==0;
#endif
#if OS_WIN
  return GetFileAttributes(zFilename) != 0xffffffff;
#endif
#if OS_MAC
  return access(zFilename, 0)==0;
#endif
}


#if 0 /* NOT USED */
/*
** Change the name of an existing file.
*/
int sqliteOsFileRename(const char *zOldName, const char *zNewName){
#if OS_UNIX
  if( link(zOldName, zNewName) ){
    return SQLITE_ERROR;
  }
  unlink(zOldName);
  return SQLITE_OK;
#endif
#if OS_WIN
  if( !MoveFile(zOldName, zNewName) ){
    return SQLITE_ERROR;
  }
  return SQLITE_OK;
#endif
#if OS_MAC
  /**** FIX ME ***/
  return SQLITE_ERROR;
#endif
}
#endif /* NOT USED */

/*
** Attempt to open a file for both reading and writing.  If that
** fails, try opening it read-only.  If the file does not exist,
** try to create it.
**
** On success, a handle for the open file is written to *id
** and *pReadonly is set to 0 if the file was opened for reading and
** writing or 1 if the file was opened read-only.  The function returns
** SQLITE_OK.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id and *pReadonly unchanged.
*/
int sqlite3OsOpenReadWrite(
  const char *zFilename,
  OsFile *id,
  int *pReadonly
){
#if OS_UNIX
  int rc;
  id->dirfd = -1;
  id->fd = open(zFilename, O_RDWR|O_CREAT|O_LARGEFILE|O_BINARY, 0644);
  if( id->fd<0 ){
    id->fd = open(zFilename, O_RDONLY|O_LARGEFILE|O_BINARY);
    if( id->fd<0 ){
      return SQLITE_CANTOPEN; 
    }
    *pReadonly = 1;
  }else{
    *pReadonly = 0;
  }
  sqlite3OsEnterMutex();
  rc = findLockInfo(id->fd, &id->pLock, &id->pOpen);
  sqlite3OsLeaveMutex();
  if( rc ){
    close(id->fd);
    return SQLITE_NOMEM;
  }
  id->locked = 0;
  TRACE3("OPEN    %-3d %s\n", id->fd, zFilename);
  OpenCounter(+1);
  return SQLITE_OK;
#endif
#if OS_WIN
  HANDLE h = CreateFile(zFilename,
     GENERIC_READ | GENERIC_WRITE,
     FILE_SHARE_READ | FILE_SHARE_WRITE,
     NULL,
     OPEN_ALWAYS,
     FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
     NULL
  );
  if( h==INVALID_HANDLE_VALUE ){
    h = CreateFile(zFilename,
       GENERIC_READ,
       FILE_SHARE_READ,
       NULL,
       OPEN_ALWAYS,
       FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
       NULL
    );
    if( h==INVALID_HANDLE_VALUE ){
      return SQLITE_CANTOPEN;
    }
    *pReadonly = 1;
  }else{
    *pReadonly = 0;
  }
  id->h = h;
  id->locked = 0;
  OpenCounter(+1);
  return SQLITE_OK;
#endif
#if OS_MAC
  FSSpec fsSpec;
# ifdef _LARGE_FILE
  HFSUniStr255 dfName;
  FSRef fsRef;
  if( __path2fss(zFilename, &fsSpec) != noErr ){
    if( HCreate(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, 'SQLI', cDocumentFile) != noErr )
      return SQLITE_CANTOPEN;
  }
  if( FSpMakeFSRef(&fsSpec, &fsRef) != noErr )
    return SQLITE_CANTOPEN;
  FSGetDataForkName(&dfName);
  if( FSOpenFork(&fsRef, dfName.length, dfName.unicode,
                 fsRdWrShPerm, &(id->refNum)) != noErr ){
    if( FSOpenFork(&fsRef, dfName.length, dfName.unicode,
                   fsRdWrPerm, &(id->refNum)) != noErr ){
      if (FSOpenFork(&fsRef, dfName.length, dfName.unicode,
                   fsRdPerm, &(id->refNum)) != noErr )
        return SQLITE_CANTOPEN;
      else
        *pReadonly = 1;
    } else
      *pReadonly = 0;
  } else
    *pReadonly = 0;
# else
  __path2fss(zFilename, &fsSpec);
  if( !sqlite3OsFileExists(zFilename) ){
    if( HCreate(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, 'SQLI', cDocumentFile) != noErr )
      return SQLITE_CANTOPEN;
  }
  if( HOpenDF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdWrShPerm, &(id->refNum)) != noErr ){
    if( HOpenDF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdWrPerm, &(id->refNum)) != noErr ){
      if( HOpenDF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdPerm, &(id->refNum)) != noErr )
        return SQLITE_CANTOPEN;
      else
        *pReadonly = 1;
    } else
      *pReadonly = 0;
  } else
    *pReadonly = 0;
# endif
  if( HOpenRF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdWrShPerm, &(id->refNumRF)) != noErr){
    id->refNumRF = -1;
  }
  id->locked = 0;
  id->delOnClose = 0;
  OpenCounter(+1);
  return SQLITE_OK;
#endif
}


/*
** Attempt to open a new file for exclusive access by this process.
** The file will be opened for both reading and writing.  To avoid
** a potential security problem, we do not allow the file to have
** previously existed.  Nor do we allow the file to be a symbolic
** link.
**
** If delFlag is true, then make arrangements to automatically delete
** the file when it is closed.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenExclusive(const char *zFilename, OsFile *id, int delFlag){
#if OS_UNIX
  int rc;
  if( access(zFilename, 0)==0 ){
    return SQLITE_CANTOPEN;
  }
  id->dirfd = -1;
  id->fd = open(zFilename,
                O_RDWR|O_CREAT|O_EXCL|O_NOFOLLOW|O_LARGEFILE|O_BINARY, 0600);
  if( id->fd<0 ){
    return SQLITE_CANTOPEN;
  }
  sqlite3OsEnterMutex();
  rc = findLockInfo(id->fd, &id->pLock, &id->pOpen);
  sqlite3OsLeaveMutex();
  if( rc ){
    close(id->fd);
    unlink(zFilename);
    return SQLITE_NOMEM;
  }
  id->locked = 0;
  if( delFlag ){
    unlink(zFilename);
  }
  TRACE3("OPEN-EX %-3d %s\n", id->fd, zFilename);
  OpenCounter(+1);
  return SQLITE_OK;
#endif
#if OS_WIN
  HANDLE h;
  int fileflags;
  if( delFlag ){
    fileflags = FILE_ATTRIBUTE_TEMPORARY | FILE_FLAG_RANDOM_ACCESS 
                     | FILE_FLAG_DELETE_ON_CLOSE;
  }else{
    fileflags = FILE_FLAG_RANDOM_ACCESS;
  }
  h = CreateFile(zFilename,
     GENERIC_READ | GENERIC_WRITE,
     0,
     NULL,
     CREATE_ALWAYS,
     fileflags,
     NULL
  );
  if( h==INVALID_HANDLE_VALUE ){
    return SQLITE_CANTOPEN;
  }
  id->h = h;
  id->locked = 0;
  OpenCounter(+1);
  return SQLITE_OK;
#endif
#if OS_MAC
  FSSpec fsSpec;
# ifdef _LARGE_FILE
  HFSUniStr255 dfName;
  FSRef fsRef;
  __path2fss(zFilename, &fsSpec);
  if( HCreate(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, 'SQLI', cDocumentFile) != noErr )
    return SQLITE_CANTOPEN;
  if( FSpMakeFSRef(&fsSpec, &fsRef) != noErr )
    return SQLITE_CANTOPEN;
  FSGetDataForkName(&dfName);
  if( FSOpenFork(&fsRef, dfName.length, dfName.unicode,
                 fsRdWrPerm, &(id->refNum)) != noErr )
    return SQLITE_CANTOPEN;
# else
  __path2fss(zFilename, &fsSpec);
  if( HCreate(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, 'SQLI', cDocumentFile) != noErr )
    return SQLITE_CANTOPEN;
  if( HOpenDF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdWrPerm, &(id->refNum)) != noErr )
    return SQLITE_CANTOPEN;
# endif
  id->refNumRF = -1;
  id->locked = 0;
  id->delOnClose = delFlag;
  if (delFlag)
    id->pathToDel = sqlite3OsFullPathname(zFilename);
  OpenCounter(+1);
  return SQLITE_OK;
#endif
}

/*
** Attempt to open a new file for read-only access.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenReadOnly(const char *zFilename, OsFile *id){
#if OS_UNIX
  int rc;
  id->dirfd = -1;
  id->fd = open(zFilename, O_RDONLY|O_LARGEFILE|O_BINARY);
  if( id->fd<0 ){
    return SQLITE_CANTOPEN;
  }
  sqlite3OsEnterMutex();
  rc = findLockInfo(id->fd, &id->pLock, &id->pOpen);
  sqlite3OsLeaveMutex();
  if( rc ){
    close(id->fd);
    return SQLITE_NOMEM;
  }
  id->locked = 0;
  TRACE3("OPEN-RO %-3d %s\n", id->fd, zFilename);
  OpenCounter(+1);
  return SQLITE_OK;
#endif
#if OS_WIN
  HANDLE h = CreateFile(zFilename,
     GENERIC_READ,
     0,
     NULL,
     OPEN_EXISTING,
     FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
     NULL
  );
  if( h==INVALID_HANDLE_VALUE ){
    return SQLITE_CANTOPEN;
  }
  id->h = h;
  id->locked = 0;
  OpenCounter(+1);
  return SQLITE_OK;
#endif
#if OS_MAC
  FSSpec fsSpec;
# ifdef _LARGE_FILE
  HFSUniStr255 dfName;
  FSRef fsRef;
  if( __path2fss(zFilename, &fsSpec) != noErr )
    return SQLITE_CANTOPEN;
  if( FSpMakeFSRef(&fsSpec, &fsRef) != noErr )
    return SQLITE_CANTOPEN;
  FSGetDataForkName(&dfName);
  if( FSOpenFork(&fsRef, dfName.length, dfName.unicode,
                 fsRdPerm, &(id->refNum)) != noErr )
    return SQLITE_CANTOPEN;
# else
  __path2fss(zFilename, &fsSpec);
  if( HOpenDF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdPerm, &(id->refNum)) != noErr )
    return SQLITE_CANTOPEN;
# endif
  if( HOpenRF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdWrShPerm, &(id->refNumRF)) != noErr){
    id->refNumRF = -1;
  }
  id->locked = 0;
  id->delOnClose = 0;
  OpenCounter(+1);
  return SQLITE_OK;
#endif
}

/*
** Attempt to open a file descriptor for the directory that contains a
** file.  This file descriptor can be used to fsync() the directory
** in order to make sure the creation of a new file is actually written
** to disk.
**
** This routine is only meaningful for Unix.  It is a no-op under
** windows since windows does not support hard links.
**
** On success, a handle for a previously open file is at *id is
** updated with the new directory file descriptor and SQLITE_OK is
** returned.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id unchanged.
*/
int sqlite3OsOpenDirectory(
  const char *zDirname,
  OsFile *id
){
#if OS_UNIX
  if( id->fd<0 ){
    /* Do not open the directory if the corresponding file is not already
    ** open. */
    return SQLITE_CANTOPEN;
  }
  assert( id->dirfd<0 );
  id->dirfd = open(zDirname, O_RDONLY|O_BINARY, 0644);
  if( id->dirfd<0 ){
    return SQLITE_CANTOPEN; 
  }
  TRACE3("OPENDIR %-3d %s\n", id->dirfd, zDirname);
#endif
  return SQLITE_OK;
}

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at least SQLITE_TEMPNAME_SIZE characters.
*/
int sqlite3OsTempFileName(char *zBuf){
#if OS_UNIX
  static const char *azDirs[] = {
     "/var/tmp",
     "/usr/tmp",
     "/tmp",
     ".",
  };
  static unsigned char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  struct stat buf;
  const char *zDir = ".";
  for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); i++){
    if( stat(azDirs[i], &buf) ) continue;
    if( !S_ISDIR(buf.st_mode) ) continue;
    if( access(azDirs[i], 07) ) continue;
    zDir = azDirs[i];
    break;
  }
  do{
    sprintf(zBuf, "%s/"TEMP_FILE_PREFIX, zDir);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
  }while( access(zBuf,0)==0 );
#endif
#if OS_WIN
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  char zTempPath[SQLITE_TEMPNAME_SIZE];
  GetTempPath(SQLITE_TEMPNAME_SIZE-30, zTempPath);
  for(i=strlen(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){}
  zTempPath[i] = 0;
  for(;;){
    sprintf(zBuf, "%s\\"TEMP_FILE_PREFIX, zTempPath);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
    if( !sqlite3OsFileExists(zBuf) ) break;
  }
#endif
#if OS_MAC
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  char zTempPath[SQLITE_TEMPNAME_SIZE];
  char zdirName[32];
  CInfoPBRec infoRec;
  Str31 dirName;
  memset(&infoRec, 0, sizeof(infoRec));
  memset(zTempPath, 0, SQLITE_TEMPNAME_SIZE);
  if( FindFolder(kOnSystemDisk, kTemporaryFolderType,  kCreateFolder,
       &(infoRec.dirInfo.ioVRefNum), &(infoRec.dirInfo.ioDrParID)) == noErr ){
    infoRec.dirInfo.ioNamePtr = dirName;
    do{
      infoRec.dirInfo.ioFDirIndex = -1;
      infoRec.dirInfo.ioDrDirID = infoRec.dirInfo.ioDrParID;
      if( PBGetCatInfoSync(&infoRec) == noErr ){
        CopyPascalStringToC(dirName, zdirName);
        i = strlen(zdirName);
        memmove(&(zTempPath[i+1]), zTempPath, strlen(zTempPath));
        strcpy(zTempPath, zdirName);
        zTempPath[i] = ':';
      }else{
        *zTempPath = 0;
        break;
      }
    } while( infoRec.dirInfo.ioDrDirID != fsRtDirID );
  }
  if( *zTempPath == 0 )
    getcwd(zTempPath, SQLITE_TEMPNAME_SIZE-24);
  for(;;){
    sprintf(zBuf, "%s"TEMP_FILE_PREFIX, zTempPath);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
    if( !sqlite3OsFileExists(zBuf) ) break;
  }
#endif
  return SQLITE_OK; 
}

/*
** Close a file.
*/
int sqlite3OsClose(OsFile *id){
#if OS_UNIX
  sqlite3OsUnlock(id);
  if( id->dirfd>=0 ) close(id->dirfd);
  id->dirfd = -1;
  sqlite3OsEnterMutex();
  if( id->pOpen->nLock ){
    /* If there are outstanding locks, do not actually close the file just
    ** yet because that would clear those locks.  Instead, add the file
    ** descriptor to pOpen->aPending.  It will be automatically closed when
    ** the last lock is cleared.
    */
    int *aNew;
    struct openCnt *pOpen = id->pOpen;
    pOpen->nPending++;
    aNew = sqliteRealloc( pOpen->aPending, pOpen->nPending*sizeof(int) );
    if( aNew==0 ){
      /* If a malloc fails, just leak the file descriptor */
    }else{
      pOpen->aPending = aNew;
      pOpen->aPending[pOpen->nPending-1] = id->fd;
    }
  }else{
    /* There are no outstanding locks so we can close the file immediately */
    close(id->fd);
  }
  releaseLockInfo(id->pLock);
  releaseOpenCnt(id->pOpen);
  sqlite3OsLeaveMutex();
  TRACE2("CLOSE   %-3d\n", id->fd);
  OpenCounter(-1);
  return SQLITE_OK;
#endif
#if OS_WIN
  CloseHandle(id->h);
  OpenCounter(-1);
  return SQLITE_OK;
#endif
#if OS_MAC
  if( id->refNumRF!=-1 )
    FSClose(id->refNumRF);
# ifdef _LARGE_FILE
  FSCloseFork(id->refNum);
# else
  FSClose(id->refNum);
# endif
  if( id->delOnClose ){
    unlink(id->pathToDel);
    sqliteFree(id->pathToDel);
  }
  OpenCounter(-1);
  return SQLITE_OK;
#endif
}

/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
int sqlite3OsRead(OsFile *id, void *pBuf, int amt){
#if OS_UNIX
  int got;
  SimulateIOError(SQLITE_IOERR);
  TIMER_START;
  got = read(id->fd, pBuf, amt);
  TIMER_END;
  TRACE4("READ    %-3d %7d %d\n", id->fd, last_page, elapse);
  SEEK(0);
  /* if( got<0 ) got = 0; */
  if( got==amt ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
#endif
#if OS_WIN
  DWORD got;
  SimulateIOError(SQLITE_IOERR);
  TRACE2("READ %d\n", last_page);
  if( !ReadFile(id->h, pBuf, amt, &got, 0) ){
    got = 0;
  }
  if( got==(DWORD)amt ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
#endif
#if OS_MAC
  int got;
  SimulateIOError(SQLITE_IOERR);
  TRACE2("READ %d\n", last_page);
# ifdef _LARGE_FILE
  FSReadFork(id->refNum, fsAtMark, 0, (ByteCount)amt, pBuf, (ByteCount*)&got);
# else
  got = amt;
  FSRead(id->refNum, &got, pBuf);
# endif
  if( got==amt ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
#endif
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
int sqlite3OsWrite(OsFile *id, const void *pBuf, int amt){
#if OS_UNIX
  int wrote = 0;
  SimulateIOError(SQLITE_IOERR);
  TIMER_START;
  while( amt>0 && (wrote = write(id->fd, pBuf, amt))>0 ){
    amt -= wrote;
    pBuf = &((char*)pBuf)[wrote];
  }
  TIMER_END;
  TRACE4("WRITE   %-3d %7d %d\n", id->fd, last_page, elapse);
  SEEK(0);
  if( amt>0 ){
    return SQLITE_FULL;
  }
  return SQLITE_OK;
#endif
#if OS_WIN
  int rc;
  DWORD wrote;
  SimulateIOError(SQLITE_IOERR);
  TRACE2("WRITE %d\n", last_page);
  while( amt>0 && (rc = WriteFile(id->h, pBuf, amt, &wrote, 0))!=0 && wrote>0 ){
    amt -= wrote;
    pBuf = &((char*)pBuf)[wrote];
  }
  if( !rc || amt>(int)wrote ){
    return SQLITE_FULL;
  }
  return SQLITE_OK;
#endif
#if OS_MAC
  OSErr oserr;
  int wrote = 0;
  SimulateIOError(SQLITE_IOERR);
  TRACE2("WRITE %d\n", last_page);
  while( amt>0 ){
# ifdef _LARGE_FILE
    oserr = FSWriteFork(id->refNum, fsAtMark, 0,
                        (ByteCount)amt, pBuf, (ByteCount*)&wrote);
# else
    wrote = amt;
    oserr = FSWrite(id->refNum, &wrote, pBuf);
# endif
    if( wrote == 0 || oserr != noErr)
      break;
    amt -= wrote;
    pBuf = &((char*)pBuf)[wrote];
  }
  if( oserr != noErr || amt>wrote ){
    return SQLITE_FULL;
  }
  return SQLITE_OK;
#endif
}

/*
** Move the read/write pointer in a file.
*/
int sqlite3OsSeek(OsFile *id, off_t offset){
  SEEK(offset/1024 + 1);
#if OS_UNIX
  lseek(id->fd, offset, SEEK_SET);
  return SQLITE_OK;
#endif
#if OS_WIN
  {
    LONG upperBits = offset>>32;
    LONG lowerBits = offset & 0xffffffff;
    DWORD rc;
    rc = SetFilePointer(id->h, lowerBits, &upperBits, FILE_BEGIN);
    /* TRACE3("SEEK rc=0x%x upper=0x%x\n", rc, upperBits); */
  }
  return SQLITE_OK;
#endif
#if OS_MAC
  {
    off_t curSize;
    if( sqlite3OsFileSize(id, &curSize) != SQLITE_OK ){
      return SQLITE_IOERR;
    }
    if( offset >= curSize ){
      if( sqlite3OsTruncate(id, offset+1) != SQLITE_OK ){
        return SQLITE_IOERR;
      }
    }
# ifdef _LARGE_FILE
    if( FSSetForkPosition(id->refNum, fsFromStart, offset) != noErr ){
# else
    if( SetFPos(id->refNum, fsFromStart, offset) != noErr ){
# endif
      return SQLITE_IOERR;
    }else{
      return SQLITE_OK;
    }
  }
#endif
}

/*
** Make sure all writes to a particular file are committed to disk.
**
** Under Unix, also make sure that the directory entry for the file
** has been created by fsync-ing the directory that contains the file.
** If we do not do this and we encounter a power failure, the directory
** entry for the journal might not exist after we reboot.  The next
** SQLite to access the file will not know that the journal exists (because
** the directory entry for the journal was never created) and the transaction
** will not roll back - possibly leading to database corruption.
*/
int sqlite3OsSync(OsFile *id){
#if OS_UNIX
  SimulateIOError(SQLITE_IOERR);
  TRACE2("SYNC    %-3d\n", id->fd);
  if( fsync(id->fd) ){
    return SQLITE_IOERR;
  }else{
    if( id->dirfd>=0 ){
      TRACE2("DIRSYNC %-3d\n", id->dirfd);
      fsync(id->dirfd);
      close(id->dirfd);  /* Only need to sync once, so close the directory */
      id->dirfd = -1;    /* when we are done. */
    }
    return SQLITE_OK;
  }
#endif
#if OS_WIN
  if( FlushFileBuffers(id->h) ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
#endif
#if OS_MAC
# ifdef _LARGE_FILE
  if( FSFlushFork(id->refNum) != noErr ){
# else
  ParamBlockRec params;
  memset(&params, 0, sizeof(ParamBlockRec));
  params.ioParam.ioRefNum = id->refNum;
  if( PBFlushFileSync(&params) != noErr ){
# endif
    return SQLITE_IOERR;
  }else{
    return SQLITE_OK;
  }
#endif
}

/*
** Truncate an open file to a specified size
*/
int sqlite3OsTruncate(OsFile *id, off_t nByte){
  SimulateIOError(SQLITE_IOERR);
#if OS_UNIX
  return ftruncate(id->fd, nByte)==0 ? SQLITE_OK : SQLITE_IOERR;
#endif
#if OS_WIN
  {
    LONG upperBits = nByte>>32;
    SetFilePointer(id->h, nByte, &upperBits, FILE_BEGIN);
    SetEndOfFile(id->h);
  }
  return SQLITE_OK;
#endif
#if OS_MAC
# ifdef _LARGE_FILE
  if( FSSetForkSize(id->refNum, fsFromStart, nByte) != noErr){
# else
  if( SetEOF(id->refNum, nByte) != noErr ){
# endif
    return SQLITE_IOERR;
  }else{
    return SQLITE_OK;
  }
#endif
}

/*
** Determine the current size of a file in bytes
*/
int sqlite3OsFileSize(OsFile *id, off_t *pSize){
#if OS_UNIX
  struct stat buf;
  SimulateIOError(SQLITE_IOERR);
  if( fstat(id->fd, &buf)!=0 ){
    return SQLITE_IOERR;
  }
  *pSize = buf.st_size;
  return SQLITE_OK;
#endif
#if OS_WIN
  DWORD upperBits, lowerBits;
  SimulateIOError(SQLITE_IOERR);
  lowerBits = GetFileSize(id->h, &upperBits);
  *pSize = (((off_t)upperBits)<<32) + lowerBits;
  return SQLITE_OK;
#endif
#if OS_MAC
# ifdef _LARGE_FILE
  if( FSGetForkSize(id->refNum, pSize) != noErr){
# else
  if( GetEOF(id->refNum, pSize) != noErr ){
# endif
    return SQLITE_IOERR;
  }else{
    return SQLITE_OK;
  }
#endif
}

#if OS_WIN
/*
** Return true (non-zero) if we are running under WinNT, Win2K or WinXP.
** Return false (zero) for Win95, Win98, or WinME.
**
** Here is an interesting observation:  Win95, Win98, and WinME lack
** the LockFileEx() API.  But we can still statically link against that
** API as long as we don't call it win running Win95/98/ME.  A call to
** this routine is used to determine if the host is Win95/98/ME or
** WinNT/2K/XP so that we will know whether or not we can safely call
** the LockFileEx() API.
*/
int isNT(void){
  static int osType = 0;   /* 0=unknown 1=win95 2=winNT */
  if( osType==0 ){
    OSVERSIONINFO sInfo;
    sInfo.dwOSVersionInfoSize = sizeof(sInfo);
    GetVersionEx(&sInfo);
    osType = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
  }
  return osType==2;
}
#endif

/*
** Windows file locking notes:  [similar issues apply to MacOS]
**
** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because
** those functions are not available.  So we use only LockFile() and
** UnlockFile().
**
** LockFile() prevents not just writing but also reading by other processes.
** (This is a design error on the part of Windows, but there is nothing
** we can do about that.)  So the region used for locking is at the
** end of the file where it is unlikely to ever interfere with an
** actual read attempt.
**
** A database read lock is obtained by locking a single randomly-chosen 
** byte out of a specific range of bytes. The lock byte is obtained at 
** random so two separate readers can probably access the file at the 
** same time, unless they are unlucky and choose the same lock byte.
** A database write lock is obtained by locking all bytes in the range.
** There can only be one writer.
**
** A lock is obtained on the first byte of the lock range before acquiring
** either a read lock or a write lock.  This prevents two processes from
** attempting to get a lock at a same time.  The semantics of 
** sqlite3OsReadLock() require that if there is already a write lock, that
** lock is converted into a read lock atomically.  The lock on the first
** byte allows us to drop the old write lock and get the read lock without
** another process jumping into the middle and messing us up.  The same
** argument applies to sqlite3OsWriteLock().
**
** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available,
** which means we can use reader/writer locks.  When reader writer locks
** are used, the lock is placed on the same range of bytes that is used
** for probabilistic locking in Win95/98/ME.  Hence, the locking scheme
** will support two or more Win95 readers or two or more WinNT readers.
** But a single Win95 reader will lock out all WinNT readers and a single
** WinNT reader will lock out all other Win95 readers.
**
** Note: On MacOS we use the resource fork for locking.
**
** The following #defines specify the range of bytes used for locking.
** N_LOCKBYTE is the number of bytes available for doing the locking.
** The first byte used to hold the lock while the lock is changing does
** not count toward this number.  FIRST_LOCKBYTE is the address of
** the first byte in the range of bytes used for locking.
*/
#define N_LOCKBYTE       10239
#if OS_MAC
# define FIRST_LOCKBYTE   (0x000fffff - N_LOCKBYTE)
#else
# define FIRST_LOCKBYTE   (0xffffffff - N_LOCKBYTE)
#endif

/*
** Change the status of the lock on the file "id" to be a readlock.
** If the file was write locked, then this reduces the lock to a read.
** If the file was read locked, then this acquires a new read lock.
**
** Return SQLITE_OK on success and SQLITE_BUSY on failure.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsReadLock(OsFile *id){
#if OS_UNIX
  int rc;
  sqlite3OsEnterMutex();
  if( id->pLock->cnt>0 ){
    if( !id->locked ){
      id->pLock->cnt++;
      id->locked = 1;
      id->pOpen->nLock++;
    }
    rc = SQLITE_OK;
  }else if( id->locked || id->pLock->cnt==0 ){
    struct flock lock;
    int s;
    lock.l_type = F_RDLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start = lock.l_len = 0L;
    s = fcntl(id->fd, F_SETLK, &lock);
    if( s!=0 ){
      rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY;
    }else{
      rc = SQLITE_OK;
      if( !id->locked ){
        id->pOpen->nLock++;
        id->locked = 1;
      }
      id->pLock->cnt = 1;
    }
  }else{
    rc = SQLITE_BUSY;
  }
  sqlite3OsLeaveMutex();
  return rc;
#endif
#if OS_WIN
  int rc;
  if( id->locked>0 ){
    rc = SQLITE_OK;
  }else{
    int lk;
    int res;
    int cnt = 100;
    sqlite3Randomness(sizeof(lk), &lk);
    lk = (lk & 0x7fffffff)%N_LOCKBYTE + 1;
    while( cnt-->0 && (res = LockFile(id->h, FIRST_LOCKBYTE, 0, 1, 0))==0 ){
      Sleep(1);
    }
    if( res ){
      UnlockFile(id->h, FIRST_LOCKBYTE+1, 0, N_LOCKBYTE, 0);
      if( isNT() ){
        OVERLAPPED ovlp;
        ovlp.Offset = FIRST_LOCKBYTE+1;
        ovlp.OffsetHigh = 0;
        ovlp.hEvent = 0;
        res = LockFileEx(id->h, LOCKFILE_FAIL_IMMEDIATELY, 
                          0, N_LOCKBYTE, 0, &ovlp);
      }else{
        res = LockFile(id->h, FIRST_LOCKBYTE+lk, 0, 1, 0);
      }
      UnlockFile(id->h, FIRST_LOCKBYTE, 0, 1, 0);
    }
    if( res ){
      id->locked = lk;
      rc = SQLITE_OK;
    }else{
      rc = SQLITE_BUSY;
    }
  }
  return rc;
#endif
#if OS_MAC
  int rc;
  if( id->locked>0 || id->refNumRF == -1 ){
    rc = SQLITE_OK;
  }else{
    int lk;
    OSErr res;
    int cnt = 5;
    ParamBlockRec params;
    sqlite3Randomness(sizeof(lk), &lk);
    lk = (lk & 0x7fffffff)%N_LOCKBYTE + 1;
    memset(&params, 0, sizeof(params));
    params.ioParam.ioRefNum = id->refNumRF;
    params.ioParam.ioPosMode = fsFromStart;
    params.ioParam.ioPosOffset = FIRST_LOCKBYTE;
    params.ioParam.ioReqCount = 1;
    while( cnt-->0 && (res = PBLockRangeSync(&params))!=noErr ){
      UInt32 finalTicks;
      Delay(1, &finalTicks); /* 1/60 sec */
    }
    if( res == noErr ){
      params.ioParam.ioPosOffset = FIRST_LOCKBYTE+1;
      params.ioParam.ioReqCount = N_LOCKBYTE;
      PBUnlockRangeSync(&params);
      params.ioParam.ioPosOffset = FIRST_LOCKBYTE+lk;
      params.ioParam.ioReqCount = 1;
      res = PBLockRangeSync(&params);
      params.ioParam.ioPosOffset = FIRST_LOCKBYTE;
      params.ioParam.ioReqCount = 1;
      PBUnlockRangeSync(&params);
    }
    if( res == noErr ){
      id->locked = lk;
      rc = SQLITE_OK;
    }else{
      rc = SQLITE_BUSY;
    }
  }
  return rc;
#endif
}

/*
** Change the lock status to be an exclusive or write lock.  Return
** SQLITE_OK on success and SQLITE_BUSY on a failure.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsWriteLock(OsFile *id){
#if OS_UNIX
  int rc;
  sqlite3OsEnterMutex();
  if( id->pLock->cnt==0 || (id->pLock->cnt==1 && id->locked==1) ){
    struct flock lock;
    int s;
    lock.l_type = F_WRLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start = lock.l_len = 0L;
    s = fcntl(id->fd, F_SETLK, &lock);
    if( s!=0 ){
      rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY;
    }else{
      rc = SQLITE_OK;
      if( !id->locked ){
        id->pOpen->nLock++;
        id->locked = 1;
      }
      id->pLock->cnt = -1;
    }
  }else{
    rc = SQLITE_BUSY;
  }
  sqlite3OsLeaveMutex();
  return rc;
#endif
#if OS_WIN
  int rc;
  if( id->locked<0 ){
    rc = SQLITE_OK;
  }else{
    int res;
    int cnt = 100;
    while( cnt-->0 && (res = LockFile(id->h, FIRST_LOCKBYTE, 0, 1, 0))==0 ){
      Sleep(1);
    }
    if( res ){
      if( id->locked>0 ){
        if( isNT() ){
          UnlockFile(id->h, FIRST_LOCKBYTE+1, 0, N_LOCKBYTE, 0);
        }else{
          res = UnlockFile(id->h, FIRST_LOCKBYTE + id->locked, 0, 1, 0);
        }
      }
      if( res ){
        res = LockFile(id->h, FIRST_LOCKBYTE+1, 0, N_LOCKBYTE, 0);
      }else{
        res = 0;
      }
      UnlockFile(id->h, FIRST_LOCKBYTE, 0, 1, 0);
    }
    if( res ){
      id->locked = -1;
      rc = SQLITE_OK;
    }else{
      rc = SQLITE_BUSY;
    }
  }
  return rc;
#endif
#if OS_MAC
  int rc;
  if( id->locked<0 || id->refNumRF == -1 ){
    rc = SQLITE_OK;
  }else{
    OSErr res;
    int cnt = 5;
    ParamBlockRec params;
    memset(&params, 0, sizeof(params));
    params.ioParam.ioRefNum = id->refNumRF;
    params.ioParam.ioPosMode = fsFromStart;
    params.ioParam.ioPosOffset = FIRST_LOCKBYTE;
    params.ioParam.ioReqCount = 1;
    while( cnt-->0 && (res = PBLockRangeSync(&params))!=noErr ){
      UInt32 finalTicks;
      Delay(1, &finalTicks); /* 1/60 sec */
    }
    if( res == noErr ){
      params.ioParam.ioPosOffset = FIRST_LOCKBYTE + id->locked;
      params.ioParam.ioReqCount = 1;
      if( id->locked==0 
            || PBUnlockRangeSync(&params)==noErr ){
        params.ioParam.ioPosOffset = FIRST_LOCKBYTE+1;
        params.ioParam.ioReqCount = N_LOCKBYTE;
        res = PBLockRangeSync(&params);
      }else{
        res = afpRangeNotLocked;
      }
      params.ioParam.ioPosOffset = FIRST_LOCKBYTE;
      params.ioParam.ioReqCount = 1;
      PBUnlockRangeSync(&params);
    }
    if( res == noErr ){
      id->locked = -1;
      rc = SQLITE_OK;
    }else{
      rc = SQLITE_BUSY;
    }
  }
  return rc;
#endif
}

/*
** Unlock the given file descriptor.  If the file descriptor was
** not previously locked, then this routine is a no-op.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsUnlock(OsFile *id){
#if OS_UNIX
  int rc;
  if( !id->locked ) return SQLITE_OK;
  sqlite3OsEnterMutex();
  assert( id->pLock->cnt!=0 );
  if( id->pLock->cnt>1 ){
    id->pLock->cnt--;
    rc = SQLITE_OK;
  }else{
    struct flock lock;
    int s;
    lock.l_type = F_UNLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start = lock.l_len = 0L;
    s = fcntl(id->fd, F_SETLK, &lock);
    if( s!=0 ){
      rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY;
    }else{
      rc = SQLITE_OK;
      id->pLock->cnt = 0;
    }
  }
  if( rc==SQLITE_OK ){
    /* 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.
    */
    struct openCnt *pOpen = id->pOpen;
    pOpen->nLock--;
    assert( pOpen->nLock>=0 );
    if( pOpen->nLock==0 && pOpen->nPending>0 ){
      int i;
      for(i=0; i<pOpen->nPending; i++){
        close(pOpen->aPending[i]);
      }
      sqliteFree(pOpen->aPending);
      pOpen->nPending = 0;
      pOpen->aPending = 0;
    }
  }
  sqlite3OsLeaveMutex();
  id->locked = 0;
  return rc;
#endif
#if OS_WIN
  int rc;
  if( id->locked==0 ){
    rc = SQLITE_OK;
  }else if( isNT() || id->locked<0 ){
    UnlockFile(id->h, FIRST_LOCKBYTE+1, 0, N_LOCKBYTE, 0);
    rc = SQLITE_OK;
    id->locked = 0;
  }else{
    UnlockFile(id->h, FIRST_LOCKBYTE+id->locked, 0, 1, 0);
    rc = SQLITE_OK;
    id->locked = 0;
  }
  return rc;
#endif
#if OS_MAC
  int rc;
  ParamBlockRec params;
  memset(&params, 0, sizeof(params));
  params.ioParam.ioRefNum = id->refNumRF;
  params.ioParam.ioPosMode = fsFromStart;
  if( id->locked==0 || id->refNumRF == -1 ){
    rc = SQLITE_OK;
  }else if( id->locked<0 ){
    params.ioParam.ioPosOffset = FIRST_LOCKBYTE+1;
    params.ioParam.ioReqCount = N_LOCKBYTE;
    PBUnlockRangeSync(&params);
    rc = SQLITE_OK;
    id->locked = 0;
  }else{
    params.ioParam.ioPosOffset = FIRST_LOCKBYTE+id->locked;
    params.ioParam.ioReqCount = 1;
    PBUnlockRangeSync(&params);
    rc = SQLITE_OK;
    id->locked = 0;
  }
  return rc;
#endif
}

/*
** Get information to seed the random number generator.  The seed
** is written into the buffer zBuf[256].  The calling function must
** supply a sufficiently large buffer.
*/
int sqlite3OsRandomSeed(char *zBuf){
  /* We have to initialize zBuf to prevent valgrind from reporting
  ** errors.  The reports issued by valgrind are incorrect - we would
  ** prefer that the randomness be increased by making use of the
  ** uninitialized space in zBuf - but valgrind errors tend to worry
  ** some users.  Rather than argue, it seems easier just to initialize
  ** the whole array and silence valgrind, even if that means less randomness
  ** in the random seed.
  **
  ** When testing, initializing zBuf[] to zero is all we do.  That means
  ** that we always use the same random number sequence.* This makes the
  ** tests repeatable.
  */
  memset(zBuf, 0, 256);
#if OS_UNIX && !defined(SQLITE_TEST)
  {
    int pid;
    time((time_t*)zBuf);
    pid = getpid();
    memcpy(&zBuf[sizeof(time_t)], &pid, sizeof(pid));
  }
#endif
#if OS_WIN && !defined(SQLITE_TEST)
  GetSystemTime((LPSYSTEMTIME)zBuf);
#endif
#if OS_MAC
  {
    int pid;
    Microseconds((UnsignedWide*)zBuf);
    pid = getpid();
    memcpy(&zBuf[sizeof(UnsignedWide)], &pid, sizeof(pid));
  }
#endif
  return SQLITE_OK;
}

/*
** Sleep for a little while.  Return the amount of time slept.
*/
int sqlite3OsSleep(int ms){
#if OS_UNIX
#if defined(HAVE_USLEEP) && HAVE_USLEEP
  usleep(ms*1000);
  return ms;
#else
  sleep((ms+999)/1000);
  return 1000*((ms+999)/1000);
#endif
#endif
#if OS_WIN
  Sleep(ms);
  return ms;
#endif
#if OS_MAC
  UInt32 finalTicks;
  UInt32 ticks = (((UInt32)ms+16)*3)/50;  /* 1/60 sec per tick */
  Delay(ticks, &finalTicks);
  return (int)((ticks*50)/3);
#endif
}

/*
** Static variables used for thread synchronization
*/
static int inMutex = 0;
#ifdef SQLITE_UNIX_THREADS
  static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
#endif
#ifdef SQLITE_W32_THREADS
  static CRITICAL_SECTION cs;
#endif
#ifdef SQLITE_MACOS_MULTITASKING
  static MPCriticalRegionID criticalRegion;
#endif

/*
** The following pair of routine implement mutual exclusion for
** multi-threaded processes.  Only a single thread is allowed to
** executed code that is surrounded by EnterMutex() and LeaveMutex().
**
** SQLite uses only a single Mutex.  There is not much critical
** code and what little there is executes quickly and without blocking.
*/
void sqlite3OsEnterMutex(){
#ifdef SQLITE_UNIX_THREADS
  pthread_mutex_lock(&mutex);
#endif
#ifdef SQLITE_W32_THREADS
  static int isInit = 0;
  while( !isInit ){
    static long lock = 0;
    if( InterlockedIncrement(&lock)==1 ){
      InitializeCriticalSection(&cs);
      isInit = 1;
    }else{
      Sleep(1);
    }
  }
  EnterCriticalSection(&cs);
#endif
#ifdef SQLITE_MACOS_MULTITASKING
  static volatile int notInit = 1;
  if( notInit ){
    if( notInit == 2 ) /* as close as you can get to thread safe init */
      MPYield();
    else{
      notInit = 2;
      MPCreateCriticalRegion(&criticalRegion);
      notInit = 0;
    }
  }
  MPEnterCriticalRegion(criticalRegion, kDurationForever);
#endif
  assert( !inMutex );
  inMutex = 1;
}
void sqlite3OsLeaveMutex(){
  assert( inMutex );
  inMutex = 0;
#ifdef SQLITE_UNIX_THREADS
  pthread_mutex_unlock(&mutex);
#endif
#ifdef SQLITE_W32_THREADS
  LeaveCriticalSection(&cs);
#endif
#ifdef SQLITE_MACOS_MULTITASKING
  MPExitCriticalRegion(criticalRegion);
#endif
}

/*
** Turn a relative pathname into a full pathname.  Return a pointer
** to the full pathname stored in space obtained from sqliteMalloc().
** The calling function is responsible for freeing this space once it
** is no longer needed.
*/
char *sqlite3OsFullPathname(const char *zRelative){
#if OS_UNIX
  char *zFull = 0;
  if( zRelative[0]=='/' ){
    sqlite3SetString(&zFull, zRelative, (char*)0);
  }else{
    char zBuf[5000];
    sqlite3SetString(&zFull, getcwd(zBuf, sizeof(zBuf)), "/", zRelative,
                    (char*)0);
  }
  return zFull;
#endif
#if OS_WIN
  char *zNotUsed;
  char *zFull;
  int nByte;
  nByte = GetFullPathName(zRelative, 0, 0, &zNotUsed) + 1;
  zFull = sqliteMalloc( nByte );
  if( zFull==0 ) return 0;
  GetFullPathName(zRelative, nByte, zFull, &zNotUsed);
  return zFull;
#endif
#if OS_MAC
  char *zFull = 0;
  if( zRelative[0]==':' ){
    char zBuf[_MAX_PATH+1];
    sqlite3SetString(&zFull, getcwd(zBuf, sizeof(zBuf)), &(zRelative[1]),
                    (char*)0);
  }else{
    if( strchr(zRelative, ':') ){
      sqlite3SetString(&zFull, zRelative, (char*)0);
    }else{
    char zBuf[_MAX_PATH+1];
      sqlite3SetString(&zFull, getcwd(zBuf, sizeof(zBuf)), zRelative, (char*)0);
    }
  }
  return zFull;
#endif
}

/*
** 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 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.
*/
int sqlite3OsCurrentTime(double *prNow){
#if OS_UNIX
  time_t t;
  time(&t);
  *prNow = t/86400.0 + 2440587.5;
#endif
#if OS_WIN
  FILETIME ft;
  /* FILETIME structure is a 64-bit value representing the number of 
     100-nanosecond intervals since January 1, 1601 (= JD 2305813.5). 
  */
  double now;
  GetSystemTimeAsFileTime( &ft );
  now = ((double)ft.dwHighDateTime) * 4294967296.0; 
  *prNow = (now + ft.dwLowDateTime)/864000000000.0 + 2305813.5;
#endif
#ifdef SQLITE_TEST
  if( sqlite3_current_time ){
    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
  }
#endif
  return 0;
}

** This header file (together with is companion C source-code file
** "os.c") attempt to abstract the underlying operating system so that
** the SQLite library will work on both POSIX and windows systems.
*/
#ifndef _SQLITE_OS_H_
#define _SQLITE_OS_H_

/*
** Helpful hint:  To get this to compile on HP/UX, add -D_INCLUDE_POSIX_SOURCE
** to the compiler command line.
*/

/*
** These #defines should enable >2GB file support on Posix if the
** underlying operating system supports it.  If the OS lacks
** large file support, or if the OS is windows, these should be no-ops.
**
** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
** on the compiler command line.  This is necessary if you are compiling
** on a recent machine (ex: RedHat 7.2) but you want your code to work
** on an older machine (ex: RedHat 6.0).  If you compile on RedHat 7.2
** without this option, LFS is enable.  But LFS does not exist in the kernel
** in RedHat 6.0, so the code won't work.  Hence, for maximum binary
** portability you should omit LFS.
**
** Similar is true for MacOS.  LFS is only supported on MacOS 9 and later.
*/
#ifndef SQLITE_DISABLE_LFS
# define _LARGE_FILE       1
# ifndef _FILE_OFFSET_BITS
#   define _FILE_OFFSET_BITS 64
# endif
# define _LARGEFILE_SOURCE 1
#endif

/*
** Temporary files are named starting with this prefix followed by 16 random
** alphanumeric characters, and no file extension. They are stored in the
** OS's standard temporary file directory, and are deleted prior to exit.
** If sqlite is being embedded in another program, you may wish to change the
** prefix to reflect your program's name, so that if your program exits
** prematurely, old temporary files can be easily identified. This can be done
** using -DTEMP_FILE_PREFIX=myprefix_ on the compiler command line.
*/
#ifndef TEMP_FILE_PREFIX
# define TEMP_FILE_PREFIX "sqlite_"
#endif

/*
** Figure out if we are dealing with Unix, Windows or MacOS.
**
** N.B. MacOS means Mac Classic (or Carbon). Treat Darwin (OS X) as Unix.
**      The MacOS build is designed to use CodeWarrior (tested with v8)
*/
#ifndef OS_UNIX
................................................................................
# define OS_MAC 0
# ifndef OS_WIN
#  define OS_WIN 0
# endif
#endif

/*
** A handle for an open file is stored in an OsFile object.
*/
#if OS_UNIX
# include <sys/types.h>
# include <sys/stat.h>
# include <fcntl.h>
# include <unistd.h>
  typedef struct OsFile OsFile;
  struct OsFile {
    struct openCnt *pOpen;    /* Info about all open fd's on this inode */
    struct lockInfo *pLock;   /* Info about locks on this inode */
    int fd;                   /* The file descriptor */
    int locked;               /* True if this instance holds the lock */
    int dirfd;                /* File descriptor for the directory */
  };
# define SQLITE_TEMPNAME_SIZE 200
# if defined(HAVE_USLEEP) && HAVE_USLEEP
#  define SQLITE_MIN_SLEEP_MS 1
# else
#  define SQLITE_MIN_SLEEP_MS 1000
# endif
#endif

#if OS_WIN
#include <windows.h>
#include <winbase.h>
  typedef struct OsFile OsFile;
  struct OsFile {
    HANDLE h;               /* Handle for accessing the file */
    int locked;             /* 0: unlocked, <0: write lock, >0: read lock */
  };
# if defined(_MSC_VER) || defined(__BORLANDC__)
    typedef __int64 off_t;
# else
#  if !defined(_CYGWIN_TYPES_H)
     typedef long long off_t;
#    if defined(__MINGW32__)
#      define	_OFF_T_
#    endif
#  endif
# endif
# define SQLITE_TEMPNAME_SIZE (MAX_PATH+50)
# define SQLITE_MIN_SLEEP_MS 1
#endif

#if OS_MAC
# include <unistd.h>
# include <Files.h>
  typedef struct OsFile OsFile;
  struct OsFile {
    SInt16 refNum;           /* Data fork/file reference number */
    SInt16 refNumRF;         /* Resource fork reference number (for locking) */
    int locked;              /* 0: unlocked, <0: write lock, >0: read lock */
    int delOnClose;          /* True if file is to be deleted on close */
    char *pathToDel;         /* Name of file to delete on close */
  };
# ifdef _LARGE_FILE
    typedef SInt64 off_t;
# else
    typedef SInt32 off_t;
# endif
# define SQLITE_TEMPNAME_SIZE _MAX_PATH
# define SQLITE_MIN_SLEEP_MS 17
#endif

/*
** Macros to determine whether the machine is big or little endian,
** evaluated at runtime.







*/
static const int sqlite3_one = 1;
#define SQLITE3_BIGENDIAN (*(char *)(&sqlite3_one)==0)
#define SQLITE3_LITTLEENDIAN (*(char *)(&sqlite3_one)==1)





int sqlite3OsDelete(const char*);
int sqlite3OsFileExists(const char*);
int sqliteOsFileRename(const char*, const char*);
int sqlite3OsOpenReadWrite(const char*, OsFile*, int*);
int sqlite3OsOpenExclusive(const char*, OsFile*, int);
int sqlite3OsOpenReadOnly(const char*, OsFile*);
................................................................................
int sqlite3OsRandomSeed(char*);
int sqlite3OsSleep(int ms);
int sqlite3OsCurrentTime(double*);
void sqlite3OsEnterMutex(void);
void sqlite3OsLeaveMutex(void);
char *sqlite3OsFullPathname(const char*);



#endif /* _SQLITE_OS_H_ */

** This header file (together with is companion C source-code file
** "os.c") attempt to abstract the underlying operating system so that
** the SQLite library will work on both POSIX and windows systems.
*/
#ifndef _SQLITE_OS_H_
#define _SQLITE_OS_H_










































/*
** Figure out if we are dealing with Unix, Windows or MacOS.
**
** N.B. MacOS means Mac Classic (or Carbon). Treat Darwin (OS X) as Unix.
**      The MacOS build is designed to use CodeWarrior (tested with v8)
*/
#ifndef OS_UNIX
................................................................................
# define OS_MAC 0
# ifndef OS_WIN
#  define OS_WIN 0
# endif
#endif

/*
** Invoke the appropriate operating-system specific header file.
*/
#if OS_UNIX


# include "os_unix.h"















#endif

#if OS_WIN
# include "os_win.h"


















#endif

#if OS_MAC

# include "os_mac.h"















#endif

/*


** Temporary files are named starting with this prefix followed by 16 random
** alphanumeric characters, and no file extension. They are stored in the
** OS's standard temporary file directory, and are deleted prior to exit.
** If sqlite is being embedded in another program, you may wish to change the
** prefix to reflect your program's name, so that if your program exits
** prematurely, old temporary files can be easily identified. This can be done
** using -DTEMP_FILE_PREFIX=myprefix_ on the compiler command line.
*/



#ifndef TEMP_FILE_PREFIX
# define TEMP_FILE_PREFIX "sqlite_"
#endif


int sqlite3OsDelete(const char*);
int sqlite3OsFileExists(const char*);
int sqliteOsFileRename(const char*, const char*);
int sqlite3OsOpenReadWrite(const char*, OsFile*, int*);
int sqlite3OsOpenExclusive(const char*, OsFile*, int);
int sqlite3OsOpenReadOnly(const char*, OsFile*);
................................................................................
int sqlite3OsRandomSeed(char*);
int sqlite3OsSleep(int ms);
int sqlite3OsCurrentTime(double*);
void sqlite3OsEnterMutex(void);
void sqlite3OsLeaveMutex(void);
char *sqlite3OsFullPathname(const char*);



#endif /* _SQLITE_OS_H_ */

/*
** 2004 May 22
**
** 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 macros and a little bit of code that is common to
** all of the platform-specific files (os_*.c) and is #included into those
** files.
**
** This file should be #included by the os_*.c files only.  It is not a
** general purpose header file.
*/


/*
** Macros for performance tracing.  Normally turned off.  Only works
** on i486 hardware.
*/
#if 0
static int last_page = 0;
__inline__ unsigned long long int hwtime(void){
  unsigned long long int x;
  __asm__("rdtsc\n\t"
          "mov %%edx, %%ecx\n\t"
          :"=A" (x));
  return x;
}
static unsigned long long int g_start;
static unsigned int elapse;
#define TIMER_START       g_start=hwtime()
#define TIMER_END         elapse=hwtime()-g_start
#define SEEK(X)           last_page=(X)
#define TRACE1(X)         fprintf(stderr,X)
#define TRACE2(X,Y)       fprintf(stderr,X,Y)
#define TRACE3(X,Y,Z)     fprintf(stderr,X,Y,Z)
#define TRACE4(X,Y,Z,A)   fprintf(stderr,X,Y,Z,A)
#define TRACE5(X,Y,Z,A,B) fprintf(stderr,X,Y,Z,A,B)
#else
#define TIMER_START
#define TIMER_END
#define SEEK(X)
#define TRACE1(X)
#define TRACE2(X,Y)
#define TRACE3(X,Y,Z)
#define TRACE4(X,Y,Z,A)
#define TRACE5(X,Y,Z,A,B)
#endif


/*
** If we compile with the SQLITE_TEST macro set, then the following block
** of code will give us the ability to simulate a disk I/O error.  This
** is used for testing the I/O recovery logic.
*/
#ifdef SQLITE_TEST
int sqlite3_io_error_pending = 0;
#define SimulateIOError(A)  \
   if( sqlite3_io_error_pending ) \
     if( sqlite3_io_error_pending-- == 1 ){ local_ioerr(); return A; }
static void local_ioerr(){
  sqlite3_io_error_pending = 0;  /* Really just a place to set a breakpoint */
}
#else
#define SimulateIOError(A)
#endif

/*
** When testing, keep a count of the number of open files.
*/
#ifdef SQLITE_TEST
int sqlite3_open_file_count = 0;
#define OpenCounter(X)  sqlite3_open_file_count+=(X)
#else
#define OpenCounter(X)
#endif

/*
** 2004 May 22
**
** 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 classic mac.  Mac OS X
** uses the os_unix.c file, not this one.
*/
#include "os.h"          /* Must be first to enable large file support */
#if OS_MAC               /* This file used on classic mac only */
#include "sqliteInt.h"

#include <extras.h>
#include <path2fss.h>
#include <TextUtils.h>
#include <FinderRegistry.h>
#include <Folders.h>
#include <Timer.h>
#include <OSUtils.h>

/*
** Macros used to determine whether or not to use threads.
*/
#if defined(THREADSAFE) && THREADSAFE
# include <Multiprocessing.h>
# define SQLITE_MACOS_MULTITASKING 1
#endif

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

/*
** Delete the named file
*/
int sqlite3OsDelete(const char *zFilename){
  unlink(zFilename);
  return SQLITE_OK;
}

/*
** Return TRUE if the named file exists.
*/
int sqlite3OsFileExists(const char *zFilename){
  return access(zFilename, 0)==0;
}

/*
** Attempt to open a file for both reading and writing.  If that
** fails, try opening it read-only.  If the file does not exist,
** try to create it.
**
** On success, a handle for the open file is written to *id
** and *pReadonly is set to 0 if the file was opened for reading and
** writing or 1 if the file was opened read-only.  The function returns
** SQLITE_OK.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id and *pReadonly unchanged.
*/
int sqlite3OsOpenReadWrite(
  const char *zFilename,
  OsFile *id,
  int *pReadonly
){
  FSSpec fsSpec;
# ifdef _LARGE_FILE
  HFSUniStr255 dfName;
  FSRef fsRef;
  if( __path2fss(zFilename, &fsSpec) != noErr ){
    if( HCreate(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, 'SQLI', cDocumentFile) != noErr )
      return SQLITE_CANTOPEN;
  }
  if( FSpMakeFSRef(&fsSpec, &fsRef) != noErr )
    return SQLITE_CANTOPEN;
  FSGetDataForkName(&dfName);
  if( FSOpenFork(&fsRef, dfName.length, dfName.unicode,
                 fsRdWrShPerm, &(id->refNum)) != noErr ){
    if( FSOpenFork(&fsRef, dfName.length, dfName.unicode,
                   fsRdWrPerm, &(id->refNum)) != noErr ){
      if (FSOpenFork(&fsRef, dfName.length, dfName.unicode,
                   fsRdPerm, &(id->refNum)) != noErr )
        return SQLITE_CANTOPEN;
      else
        *pReadonly = 1;
    } else
      *pReadonly = 0;
  } else
    *pReadonly = 0;
# else
  __path2fss(zFilename, &fsSpec);
  if( !sqlite3OsFileExists(zFilename) ){
    if( HCreate(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, 'SQLI', cDocumentFile) != noErr )
      return SQLITE_CANTOPEN;
  }
  if( HOpenDF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdWrShPerm, &(id->refNum)) != noErr ){
    if( HOpenDF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdWrPerm, &(id->refNum)) != noErr ){
      if( HOpenDF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdPerm, &(id->refNum)) != noErr )
        return SQLITE_CANTOPEN;
      else
        *pReadonly = 1;
    } else
      *pReadonly = 0;
  } else
    *pReadonly = 0;
# endif
  if( HOpenRF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdWrShPerm, &(id->refNumRF)) != noErr){
    id->refNumRF = -1;
  }
  id->locked = 0;
  id->delOnClose = 0;
  OpenCounter(+1);
  return SQLITE_OK;
}


/*
** Attempt to open a new file for exclusive access by this process.
** The file will be opened for both reading and writing.  To avoid
** a potential security problem, we do not allow the file to have
** previously existed.  Nor do we allow the file to be a symbolic
** link.
**
** If delFlag is true, then make arrangements to automatically delete
** the file when it is closed.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenExclusive(const char *zFilename, OsFile *id, int delFlag){
  FSSpec fsSpec;
# ifdef _LARGE_FILE
  HFSUniStr255 dfName;
  FSRef fsRef;
  __path2fss(zFilename, &fsSpec);
  if( HCreate(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, 'SQLI', cDocumentFile) != noErr )
    return SQLITE_CANTOPEN;
  if( FSpMakeFSRef(&fsSpec, &fsRef) != noErr )
    return SQLITE_CANTOPEN;
  FSGetDataForkName(&dfName);
  if( FSOpenFork(&fsRef, dfName.length, dfName.unicode,
                 fsRdWrPerm, &(id->refNum)) != noErr )
    return SQLITE_CANTOPEN;
# else
  __path2fss(zFilename, &fsSpec);
  if( HCreate(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, 'SQLI', cDocumentFile) != noErr )
    return SQLITE_CANTOPEN;
  if( HOpenDF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdWrPerm, &(id->refNum)) != noErr )
    return SQLITE_CANTOPEN;
# endif
  id->refNumRF = -1;
  id->locked = 0;
  id->delOnClose = delFlag;
  if (delFlag)
    id->pathToDel = sqlite3OsFullPathname(zFilename);
  OpenCounter(+1);
  return SQLITE_OK;
}

/*
** Attempt to open a new file for read-only access.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenReadOnly(const char *zFilename, OsFile *id){
  FSSpec fsSpec;
# ifdef _LARGE_FILE
  HFSUniStr255 dfName;
  FSRef fsRef;
  if( __path2fss(zFilename, &fsSpec) != noErr )
    return SQLITE_CANTOPEN;
  if( FSpMakeFSRef(&fsSpec, &fsRef) != noErr )
    return SQLITE_CANTOPEN;
  FSGetDataForkName(&dfName);
  if( FSOpenFork(&fsRef, dfName.length, dfName.unicode,
                 fsRdPerm, &(id->refNum)) != noErr )
    return SQLITE_CANTOPEN;
# else
  __path2fss(zFilename, &fsSpec);
  if( HOpenDF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdPerm, &(id->refNum)) != noErr )
    return SQLITE_CANTOPEN;
# endif
  if( HOpenRF(fsSpec.vRefNum, fsSpec.parID, fsSpec.name, fsRdWrShPerm, &(id->refNumRF)) != noErr){
    id->refNumRF = -1;
  }
  id->locked = 0;
  id->delOnClose = 0;
  OpenCounter(+1);
  return SQLITE_OK;
}

/*
** Attempt to open a file descriptor for the directory that contains a
** file.  This file descriptor can be used to fsync() the directory
** in order to make sure the creation of a new file is actually written
** to disk.
**
** This routine is only meaningful for Unix.  It is a no-op under
** windows since windows does not support hard links.
**
** On success, a handle for a previously open file is at *id is
** updated with the new directory file descriptor and SQLITE_OK is
** returned.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id unchanged.
*/
int sqlite3OsOpenDirectory(
  const char *zDirname,
  OsFile *id
){
  return SQLITE_OK;
}

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at least SQLITE_TEMPNAME_SIZE characters.
*/
int sqlite3OsTempFileName(char *zBuf){
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  char zTempPath[SQLITE_TEMPNAME_SIZE];
  char zdirName[32];
  CInfoPBRec infoRec;
  Str31 dirName;
  memset(&infoRec, 0, sizeof(infoRec));
  memset(zTempPath, 0, SQLITE_TEMPNAME_SIZE);
  if( FindFolder(kOnSystemDisk, kTemporaryFolderType,  kCreateFolder,
       &(infoRec.dirInfo.ioVRefNum), &(infoRec.dirInfo.ioDrParID)) == noErr ){
    infoRec.dirInfo.ioNamePtr = dirName;
    do{
      infoRec.dirInfo.ioFDirIndex = -1;
      infoRec.dirInfo.ioDrDirID = infoRec.dirInfo.ioDrParID;
      if( PBGetCatInfoSync(&infoRec) == noErr ){
        CopyPascalStringToC(dirName, zdirName);
        i = strlen(zdirName);
        memmove(&(zTempPath[i+1]), zTempPath, strlen(zTempPath));
        strcpy(zTempPath, zdirName);
        zTempPath[i] = ':';
      }else{
        *zTempPath = 0;
        break;
      }
    } while( infoRec.dirInfo.ioDrDirID != fsRtDirID );
  }
  if( *zTempPath == 0 )
    getcwd(zTempPath, SQLITE_TEMPNAME_SIZE-24);
  for(;;){
    sprintf(zBuf, "%s"TEMP_FILE_PREFIX, zTempPath);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
    if( !sqlite3OsFileExists(zBuf) ) break;
  }
  return SQLITE_OK; 
}

/*
** Close a file.
*/
int sqlite3OsClose(OsFile *id){
  if( id->refNumRF!=-1 )
    FSClose(id->refNumRF);
# ifdef _LARGE_FILE
  FSCloseFork(id->refNum);
# else
  FSClose(id->refNum);
# endif
  if( id->delOnClose ){
    unlink(id->pathToDel);
    sqliteFree(id->pathToDel);
  }
  OpenCounter(-1);
  return SQLITE_OK;
}

/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
int sqlite3OsRead(OsFile *id, void *pBuf, int amt){
  int got;
  SimulateIOError(SQLITE_IOERR);
  TRACE2("READ %d\n", last_page);
# ifdef _LARGE_FILE
  FSReadFork(id->refNum, fsAtMark, 0, (ByteCount)amt, pBuf, (ByteCount*)&got);
# else
  got = amt;
  FSRead(id->refNum, &got, pBuf);
# endif
  if( got==amt ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
int sqlite3OsWrite(OsFile *id, const void *pBuf, int amt){
  OSErr oserr;
  int wrote = 0;
  SimulateIOError(SQLITE_IOERR);
  TRACE2("WRITE %d\n", last_page);
  while( amt>0 ){
# ifdef _LARGE_FILE
    oserr = FSWriteFork(id->refNum, fsAtMark, 0,
                        (ByteCount)amt, pBuf, (ByteCount*)&wrote);
# else
    wrote = amt;
    oserr = FSWrite(id->refNum, &wrote, pBuf);
# endif
    if( wrote == 0 || oserr != noErr)
      break;
    amt -= wrote;
    pBuf = &((char*)pBuf)[wrote];
  }
  if( oserr != noErr || amt>wrote ){
    return SQLITE_FULL;
  }
  return SQLITE_OK;
}

/*
** Move the read/write pointer in a file.
*/
int sqlite3OsSeek(OsFile *id, off_t offset){
  off_t curSize;
  SEEK(offset/1024 + 1);
  if( sqlite3OsFileSize(id, &curSize) != SQLITE_OK ){
    return SQLITE_IOERR;
  }
  if( offset >= curSize ){
    if( sqlite3OsTruncate(id, offset+1) != SQLITE_OK ){
      return SQLITE_IOERR;
    }
  }
# ifdef _LARGE_FILE
  if( FSSetForkPosition(id->refNum, fsFromStart, offset) != noErr ){
# else
  if( SetFPos(id->refNum, fsFromStart, offset) != noErr ){
# endif
    return SQLITE_IOERR;
  }else{
    return SQLITE_OK;
  }
}

/*
** Make sure all writes to a particular file are committed to disk.
**
** Under Unix, also make sure that the directory entry for the file
** has been created by fsync-ing the directory that contains the file.
** If we do not do this and we encounter a power failure, the directory
** entry for the journal might not exist after we reboot.  The next
** SQLite to access the file will not know that the journal exists (because
** the directory entry for the journal was never created) and the transaction
** will not roll back - possibly leading to database corruption.
*/
int sqlite3OsSync(OsFile *id){
# ifdef _LARGE_FILE
  if( FSFlushFork(id->refNum) != noErr ){
# else
  ParamBlockRec params;
  memset(&params, 0, sizeof(ParamBlockRec));
  params.ioParam.ioRefNum = id->refNum;
  if( PBFlushFileSync(&params) != noErr ){
# endif
    return SQLITE_IOERR;
  }else{
    return SQLITE_OK;
  }
}

/*
** Truncate an open file to a specified size
*/
int sqlite3OsTruncate(OsFile *id, off_t nByte){
  SimulateIOError(SQLITE_IOERR);
# ifdef _LARGE_FILE
  if( FSSetForkSize(id->refNum, fsFromStart, nByte) != noErr){
# else
  if( SetEOF(id->refNum, nByte) != noErr ){
# endif
    return SQLITE_IOERR;
  }else{
    return SQLITE_OK;
  }
}

/*
** Determine the current size of a file in bytes
*/
int sqlite3OsFileSize(OsFile *id, off_t *pSize){
# ifdef _LARGE_FILE
  if( FSGetForkSize(id->refNum, pSize) != noErr){
# else
  if( GetEOF(id->refNum, pSize) != noErr ){
# endif
    return SQLITE_IOERR;
  }else{
    return SQLITE_OK;
  }
}

/*
** Windows file locking notes:  [similar issues apply to MacOS]
**
** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because
** those functions are not available.  So we use only LockFile() and
** UnlockFile().
**
** LockFile() prevents not just writing but also reading by other processes.
** (This is a design error on the part of Windows, but there is nothing
** we can do about that.)  So the region used for locking is at the
** end of the file where it is unlikely to ever interfere with an
** actual read attempt.
**
** A database read lock is obtained by locking a single randomly-chosen 
** byte out of a specific range of bytes. The lock byte is obtained at 
** random so two separate readers can probably access the file at the 
** same time, unless they are unlucky and choose the same lock byte.
** A database write lock is obtained by locking all bytes in the range.
** There can only be one writer.
**
** A lock is obtained on the first byte of the lock range before acquiring
** either a read lock or a write lock.  This prevents two processes from
** attempting to get a lock at a same time.  The semantics of 
** sqlite3OsReadLock() require that if there is already a write lock, that
** lock is converted into a read lock atomically.  The lock on the first
** byte allows us to drop the old write lock and get the read lock without
** another process jumping into the middle and messing us up.  The same
** argument applies to sqlite3OsWriteLock().
**
** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available,
** which means we can use reader/writer locks.  When reader writer locks
** are used, the lock is placed on the same range of bytes that is used
** for probabilistic locking in Win95/98/ME.  Hence, the locking scheme
** will support two or more Win95 readers or two or more WinNT readers.
** But a single Win95 reader will lock out all WinNT readers and a single
** WinNT reader will lock out all other Win95 readers.
**
** Note: On MacOS we use the resource fork for locking.
**
** The following #defines specify the range of bytes used for locking.
** N_LOCKBYTE is the number of bytes available for doing the locking.
** The first byte used to hold the lock while the lock is changing does
** not count toward this number.  FIRST_LOCKBYTE is the address of
** the first byte in the range of bytes used for locking.
*/
#define N_LOCKBYTE       10239
#define FIRST_LOCKBYTE   (0x000fffff - N_LOCKBYTE)

/*
** Change the status of the lock on the file "id" to be a readlock.
** If the file was write locked, then this reduces the lock to a read.
** If the file was read locked, then this acquires a new read lock.
**
** Return SQLITE_OK on success and SQLITE_BUSY on failure.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsReadLock(OsFile *id){
  int rc;
  if( id->locked>0 || id->refNumRF == -1 ){
    rc = SQLITE_OK;
  }else{
    int lk;
    OSErr res;
    int cnt = 5;
    ParamBlockRec params;
    sqlite3Randomness(sizeof(lk), &lk);
    lk = (lk & 0x7fffffff)%N_LOCKBYTE + 1;
    memset(&params, 0, sizeof(params));
    params.ioParam.ioRefNum = id->refNumRF;
    params.ioParam.ioPosMode = fsFromStart;
    params.ioParam.ioPosOffset = FIRST_LOCKBYTE;
    params.ioParam.ioReqCount = 1;
    while( cnt-->0 && (res = PBLockRangeSync(&params))!=noErr ){
      UInt32 finalTicks;
      Delay(1, &finalTicks); /* 1/60 sec */
    }
    if( res == noErr ){
      params.ioParam.ioPosOffset = FIRST_LOCKBYTE+1;
      params.ioParam.ioReqCount = N_LOCKBYTE;
      PBUnlockRangeSync(&params);
      params.ioParam.ioPosOffset = FIRST_LOCKBYTE+lk;
      params.ioParam.ioReqCount = 1;
      res = PBLockRangeSync(&params);
      params.ioParam.ioPosOffset = FIRST_LOCKBYTE;
      params.ioParam.ioReqCount = 1;
      PBUnlockRangeSync(&params);
    }
    if( res == noErr ){
      id->locked = lk;
      rc = SQLITE_OK;
    }else{
      rc = SQLITE_BUSY;
    }
  }
  return rc;
}

/*
** Change the lock status to be an exclusive or write lock.  Return
** SQLITE_OK on success and SQLITE_BUSY on a failure.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsWriteLock(OsFile *id){
  int rc;
  if( id->locked<0 || id->refNumRF == -1 ){
    rc = SQLITE_OK;
  }else{
    OSErr res;
    int cnt = 5;
    ParamBlockRec params;
    memset(&params, 0, sizeof(params));
    params.ioParam.ioRefNum = id->refNumRF;
    params.ioParam.ioPosMode = fsFromStart;
    params.ioParam.ioPosOffset = FIRST_LOCKBYTE;
    params.ioParam.ioReqCount = 1;
    while( cnt-->0 && (res = PBLockRangeSync(&params))!=noErr ){
      UInt32 finalTicks;
      Delay(1, &finalTicks); /* 1/60 sec */
    }
    if( res == noErr ){
      params.ioParam.ioPosOffset = FIRST_LOCKBYTE + id->locked;
      params.ioParam.ioReqCount = 1;
      if( id->locked==0 
            || PBUnlockRangeSync(&params)==noErr ){
        params.ioParam.ioPosOffset = FIRST_LOCKBYTE+1;
        params.ioParam.ioReqCount = N_LOCKBYTE;
        res = PBLockRangeSync(&params);
      }else{
        res = afpRangeNotLocked;
      }
      params.ioParam.ioPosOffset = FIRST_LOCKBYTE;
      params.ioParam.ioReqCount = 1;
      PBUnlockRangeSync(&params);
    }
    if( res == noErr ){
      id->locked = -1;
      rc = SQLITE_OK;
    }else{
      rc = SQLITE_BUSY;
    }
  }
  return rc;
}

/*
** Unlock the given file descriptor.  If the file descriptor was
** not previously locked, then this routine is a no-op.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsUnlock(OsFile *id){
  int rc;
  ParamBlockRec params;
  memset(&params, 0, sizeof(params));
  params.ioParam.ioRefNum = id->refNumRF;
  params.ioParam.ioPosMode = fsFromStart;
  if( id->locked==0 || id->refNumRF == -1 ){
    rc = SQLITE_OK;
  }else if( id->locked<0 ){
    params.ioParam.ioPosOffset = FIRST_LOCKBYTE+1;
    params.ioParam.ioReqCount = N_LOCKBYTE;
    PBUnlockRangeSync(&params);
    rc = SQLITE_OK;
    id->locked = 0;
  }else{
    params.ioParam.ioPosOffset = FIRST_LOCKBYTE+id->locked;
    params.ioParam.ioReqCount = 1;
    PBUnlockRangeSync(&params);
    rc = SQLITE_OK;
    id->locked = 0;
  }
  return rc;
}

/*
** Get information to seed the random number generator.  The seed
** is written into the buffer zBuf[256].  The calling function must
** supply a sufficiently large buffer.
*/
int sqlite3OsRandomSeed(char *zBuf){
  /* We have to initialize zBuf to prevent valgrind from reporting
  ** errors.  The reports issued by valgrind are incorrect - we would
  ** prefer that the randomness be increased by making use of the
  ** uninitialized space in zBuf - but valgrind errors tend to worry
  ** some users.  Rather than argue, it seems easier just to initialize
  ** the whole array and silence valgrind, even if that means less randomness
  ** in the random seed.
  **
  ** When testing, initializing zBuf[] to zero is all we do.  That means
  ** that we always use the same random number sequence.* This makes the
  ** tests repeatable.
  */
  memset(zBuf, 0, 256);
#if !defined(SQLITE_TEST)
  {
    int pid;
    Microseconds((UnsignedWide*)zBuf);
    pid = getpid();
    memcpy(&zBuf[sizeof(UnsignedWide)], &pid, sizeof(pid));
  }
#endif
  return SQLITE_OK;
}

/*
** Sleep for a little while.  Return the amount of time slept.
*/
int sqlite3OsSleep(int ms){
  UInt32 finalTicks;
  UInt32 ticks = (((UInt32)ms+16)*3)/50;  /* 1/60 sec per tick */
  Delay(ticks, &finalTicks);
  return (int)((ticks*50)/3);
}

/*
** Static variables used for thread synchronization
*/
static int inMutex = 0;
#ifdef SQLITE_MACOS_MULTITASKING
  static MPCriticalRegionID criticalRegion;
#endif

/*
** The following pair of routine implement mutual exclusion for
** multi-threaded processes.  Only a single thread is allowed to
** executed code that is surrounded by EnterMutex() and LeaveMutex().
**
** SQLite uses only a single Mutex.  There is not much critical
** code and what little there is executes quickly and without blocking.
*/
void sqlite3OsEnterMutex(){
#ifdef SQLITE_MACOS_MULTITASKING
  static volatile int notInit = 1;
  if( notInit ){
    if( notInit == 2 ) /* as close as you can get to thread safe init */
      MPYield();
    else{
      notInit = 2;
      MPCreateCriticalRegion(&criticalRegion);
      notInit = 0;
    }
  }
  MPEnterCriticalRegion(criticalRegion, kDurationForever);
#endif
  assert( !inMutex );
  inMutex = 1;
}
void sqlite3OsLeaveMutex(){
  assert( inMutex );
  inMutex = 0;
#ifdef SQLITE_MACOS_MULTITASKING
  MPExitCriticalRegion(criticalRegion);
#endif
}

/*
** Turn a relative pathname into a full pathname.  Return a pointer
** to the full pathname stored in space obtained from sqliteMalloc().
** The calling function is responsible for freeing this space once it
** is no longer needed.
*/
char *sqlite3OsFullPathname(const char *zRelative){
  char *zFull = 0;
  if( zRelative[0]==':' ){
    char zBuf[_MAX_PATH+1];
    sqlite3SetString(&zFull, getcwd(zBuf, sizeof(zBuf)), &(zRelative[1]),
                    (char*)0);
  }else{
    if( strchr(zRelative, ':') ){
      sqlite3SetString(&zFull, zRelative, (char*)0);
    }else{
    char zBuf[_MAX_PATH+1];
      sqlite3SetString(&zFull, getcwd(zBuf, sizeof(zBuf)), zRelative, (char*)0);
    }
  }
  return zFull;
}

/*
** 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 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.
*/
int sqlite3OsCurrentTime(double *prNow){
  *prNow = 0.0;   /**** FIX ME *****/
#ifdef SQLITE_TEST
  if( sqlite3_current_time ){
    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
  }
#endif
  return 0;
}

#endif /* OS_MAC */

/*
** 2004 May 22
**
** 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 header file defines OS-specific features of classic Mac.
** OS X uses the os_unix.h file, not this one.
*/
#ifndef _SQLITE_OS_MAC_H_
#define _SQLITE_OS_MAC_H_


#include <unistd.h>
#include <Files.h>
#ifdef _LARGE_FILE
    typedef SInt64 off_t;
#else
    typedef SInt32 off_t;
#endif
#define SQLITE_TEMPNAME_SIZE _MAX_PATH
#define SQLITE_MIN_SLEEP_MS 17

/*
** The OsFile structure is a operating-system independing representation
** of an open file handle.  It is defined differently for each architecture.
**
** This is the definition for class Mac.
*/
typedef struct OsFile OsFile;
struct OsFile {
  SInt16 refNum;           /* Data fork/file reference number */
  SInt16 refNumRF;         /* Resource fork reference number (for locking) */
  int locked;              /* 0: unlocked, <0: write lock, >0: read lock */
  int delOnClose;          /* True if file is to be deleted on close */
  char *pathToDel;         /* Name of file to delete on close */
};


#endif /* _SQLITE_OS_MAC_H_ */

/*
** 2004 May 22
**
** 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 Unix systems.
*/
#include "os.h"          /* Must be first to enable large file support */
#if OS_UNIX              /* This file is used on unix only */
#include "sqliteInt.h"


#include <time.h>
#include <errno.h>
#include <unistd.h>
#ifndef O_LARGEFILE
# define O_LARGEFILE 0
#endif
#ifdef SQLITE_DISABLE_LFS
# undef O_LARGEFILE
# define O_LARGEFILE 0
#endif
#ifndef O_NOFOLLOW
# define O_NOFOLLOW 0
#endif
#ifndef O_BINARY
# define O_BINARY 0
#endif

/*
** The DJGPP compiler environment looks mostly like Unix, but it
** lacks the fcntl() system call.  So redefine fcntl() to be something
** that always succeeds.  This means that locking does not occur under
** DJGPP.  But its DOS - what did you expect?
*/
#ifdef __DJGPP__
# define fcntl(A,B,C) 0
#endif

/*
** Macros used to determine whether or not to use threads.  The
** SQLITE_UNIX_THREADS macro is defined if we are synchronizing for
** Posix threads and SQLITE_W32_THREADS is defined if we are
** synchronizing using Win32 threads.
*/
#if defined(THREADSAFE) && THREADSAFE
# include <pthread.h>
# define SQLITE_UNIX_THREADS 1
#endif


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


/*
** Here is the dirt on POSIX advisory locks:  ANSI STD 1003.1 (1996)
** section 6.5.2.2 lines 483 through 490 specify that when a process
** sets or clears a lock, that operation overrides any prior locks set
** by the same process.  It does not explicitly say so, but this implies
** that it overrides locks set by the same process using a different
** file descriptor.  Consider this test case:
**
**       int fd1 = open("./file1", O_RDWR|O_CREAT, 0644);
**       int fd2 = open("./file2", O_RDWR|O_CREAT, 0644);
**
** Suppose ./file1 and ./file2 are really the same file (because
** one is a hard or symbolic link to the other) then if you set
** an exclusive lock on fd1, then try to get an exclusive lock
** on fd2, it works.  I would have expected the second lock to
** fail since there was already a lock on the file due to fd1.
** But not so.  Since both locks came from the same process, the
** second overrides the first, even though they were on different
** file descriptors opened on different file names.
**
** Bummer.  If you ask me, this is broken.  Badly broken.  It means
** that we cannot use POSIX locks to synchronize file access among
** competing threads of the same process.  POSIX locks will work fine
** to synchronize access for threads in separate processes, but not
** threads within the same process.
**
** To work around the problem, SQLite has to manage file locks internally
** on its own.  Whenever a new database is opened, we have to find the
** specific inode of the database file (the inode is determined by the
** st_dev and st_ino fields of the stat structure that fstat() fills in)
** and check for locks already existing on that inode.  When locks are
** created or removed, we have to look at our own internal record of the
** locks to see if another thread has previously set a lock on that same
** inode.
**
** The OsFile structure for POSIX is no longer just an integer file
** descriptor.  It is now a structure that holds the integer file
** descriptor and a pointer to a structure that describes the internal
** locks on the corresponding inode.  There is one locking structure
** per inode, so if the same inode is opened twice, both OsFile structures
** point to the same locking structure.  The locking structure keeps
** a reference count (so we will know when to delete it) and a "cnt"
** field that tells us its internal lock status.  cnt==0 means the
** file is unlocked.  cnt==-1 means the file has an exclusive lock.
** cnt>0 means there are cnt shared locks on the file.
**
** Any attempt to lock or unlock a file first checks the locking
** structure.  The fcntl() system call is only invoked to set a 
** POSIX lock if the internal lock structure transitions between
** a locked and an unlocked state.
**
** 2004-Jan-11:
** More recent discoveries about POSIX advisory locks.  (The more
** I discover, the more I realize the a POSIX advisory locks are
** an abomination.)
**
** If you close a file descriptor that points to a file that has locks,
** all locks on that file that are owned by the current process are
** released.  To work around this problem, each OsFile structure contains
** a pointer to an openCnt structure.  There is one openCnt structure
** per open inode, which means that multiple OsFiles can point to a single
** openCnt.  When an attempt is made to close an OsFile, if there are
** other OsFiles open on the same inode that are holding locks, the call
** to close() the file descriptor is deferred until all of the locks clear.
** The openCnt structure keeps a list of file descriptors that need to
** be closed and that list is walked (and cleared) when the last lock
** clears.
**
** First, under Linux threads, because each thread has a separate
** process ID, lock operations in one thread do not override locks
** to the same file in other threads.  Linux threads behave like
** separate processes in this respect.  But, if you close a file
** descriptor in linux threads, all locks are cleared, even locks
** on other threads and even though the other threads have different
** process IDs.  Linux threads is inconsistent in this respect.
** (I'm beginning to think that linux threads is an abomination too.)
** The consequence of this all is that the hash table for the lockInfo
** structure has to include the process id as part of its key because
** locks in different threads are treated as distinct.  But the 
** openCnt structure should not include the process id in its
** key because close() clears lock on all threads, not just the current
** thread.  Were it not for this goofiness in linux threads, we could
** combine the lockInfo and openCnt structures into a single structure.
*/

/*
** An instance of the following structure serves as the key used
** to locate a particular lockInfo structure given its inode.  Note
** that we have to include the process ID as part of the key.  On some
** threading implementations (ex: linux), each thread has a separate
** process ID.
*/
struct lockKey {
  dev_t dev;   /* Device number */
  ino_t ino;   /* Inode number */
  pid_t pid;   /* Process ID */
};

/*
** An instance of the following structure is allocated for each open
** inode on each thread with a different process ID.  (Threads have
** different process IDs on linux, but not on most other unixes.)
**
** A single inode can have multiple file descriptors, so each OsFile
** structure contains a pointer to an instance of this object and this
** object keeps a count of the number of OsFiles pointing to it.
*/
struct lockInfo {
  struct lockKey key;  /* The lookup key */
  int cnt;             /* 0: unlocked.  -1: write lock.  1...: read lock. */
  int nRef;            /* Number of pointers to this structure */
};

/*
** An instance of the following structure serves as the key used
** to locate a particular openCnt structure given its inode.  This
** is the same as the lockKey except that the process ID is omitted.
*/
struct openKey {
  dev_t dev;   /* Device number */
  ino_t ino;   /* Inode number */
};

/*
** An instance of the following structure is allocated for each open
** inode.  This structure keeps track of the number of locks on that
** inode.  If a close is attempted against an inode that is holding
** locks, the close is deferred until all locks clear by adding the
** file descriptor to be closed to the pending list.
*/
struct openCnt {
  struct openKey key;   /* The lookup key */
  int nRef;             /* Number of pointers to this structure */
  int nLock;            /* Number of outstanding locks */
  int nPending;         /* Number of pending close() operations */
  int *aPending;        /* Malloced space holding fd's awaiting a close() */
};

/* 
** These hash table maps inodes and process IDs into lockInfo and openCnt
** structures.  Access to these hash tables must be protected by a mutex.
*/
static Hash lockHash = { SQLITE_HASH_BINARY, 0, 0, 0, 0, 0 };
static Hash openHash = { SQLITE_HASH_BINARY, 0, 0, 0, 0, 0 };

/*
** Release a lockInfo structure previously allocated by findLockInfo().
*/
static void releaseLockInfo(struct lockInfo *pLock){
  pLock->nRef--;
  if( pLock->nRef==0 ){
    sqlite3HashInsert(&lockHash, &pLock->key, sizeof(pLock->key), 0);
    sqliteFree(pLock);
  }
}

/*
** Release a openCnt structure previously allocated by findLockInfo().
*/
static void releaseOpenCnt(struct openCnt *pOpen){
  pOpen->nRef--;
  if( pOpen->nRef==0 ){
    sqlite3HashInsert(&openHash, &pOpen->key, sizeof(pOpen->key), 0);
    sqliteFree(pOpen->aPending);
    sqliteFree(pOpen);
  }
}

/*
** Given a file descriptor, locate lockInfo and openCnt structures that
** describes that file descriptor.  Create a new ones if necessary.  The
** return values might be unset if an error occurs.
**
** Return the number of errors.
*/
int findLockInfo(
  int fd,                      /* The file descriptor used in the key */
  struct lockInfo **ppLock,    /* Return the lockInfo structure here */
  struct openCnt **ppOpen   /* Return the openCnt structure here */
){
  int rc;
  struct lockKey key1;
  struct openKey key2;
  struct stat statbuf;
  struct lockInfo *pLock;
  struct openCnt *pOpen;
  rc = fstat(fd, &statbuf);
  if( rc!=0 ) return 1;
  memset(&key1, 0, sizeof(key1));
  key1.dev = statbuf.st_dev;
  key1.ino = statbuf.st_ino;
  key1.pid = getpid();
  memset(&key2, 0, sizeof(key2));
  key2.dev = statbuf.st_dev;
  key2.ino = statbuf.st_ino;
  pLock = (struct lockInfo*)sqlite3HashFind(&lockHash, &key1, sizeof(key1));
  if( pLock==0 ){
    struct lockInfo *pOld;
    pLock = sqliteMallocRaw( sizeof(*pLock) );
    if( pLock==0 ) return 1;
    pLock->key = key1;
    pLock->nRef = 1;
    pLock->cnt = 0;
    pOld = sqlite3HashInsert(&lockHash, &pLock->key, sizeof(key1), pLock);
    if( pOld!=0 ){
      assert( pOld==pLock );
      sqliteFree(pLock);
      return 1;
    }
  }else{
    pLock->nRef++;
  }
  *ppLock = pLock;
  pOpen = (struct openCnt*)sqlite3HashFind(&openHash, &key2, sizeof(key2));
  if( pOpen==0 ){
    struct openCnt *pOld;
    pOpen = sqliteMallocRaw( sizeof(*pOpen) );
    if( pOpen==0 ){
      releaseLockInfo(pLock);
      return 1;
    }
    pOpen->key = key2;
    pOpen->nRef = 1;
    pOpen->nLock = 0;
    pOpen->nPending = 0;
    pOpen->aPending = 0;
    pOld = sqlite3HashInsert(&openHash, &pOpen->key, sizeof(key2), pOpen);
    if( pOld!=0 ){
      assert( pOld==pOpen );
      sqliteFree(pOpen);
      releaseLockInfo(pLock);
      return 1;
    }
  }else{
    pOpen->nRef++;
  }
  *ppOpen = pOpen;
  return 0;
}

/*
** Delete the named file
*/
int sqlite3OsDelete(const char *zFilename){
  unlink(zFilename);
  return SQLITE_OK;
}

/*
** Return TRUE if the named file exists.
*/
int sqlite3OsFileExists(const char *zFilename){
  return access(zFilename, 0)==0;
}

/*
** Attempt to open a file for both reading and writing.  If that
** fails, try opening it read-only.  If the file does not exist,
** try to create it.
**
** On success, a handle for the open file is written to *id
** and *pReadonly is set to 0 if the file was opened for reading and
** writing or 1 if the file was opened read-only.  The function returns
** SQLITE_OK.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id and *pReadonly unchanged.
*/
int sqlite3OsOpenReadWrite(
  const char *zFilename,
  OsFile *id,
  int *pReadonly
){
  int rc;
  id->dirfd = -1;
  id->fd = open(zFilename, O_RDWR|O_CREAT|O_LARGEFILE|O_BINARY, 0644);
  if( id->fd<0 ){
    id->fd = open(zFilename, O_RDONLY|O_LARGEFILE|O_BINARY);
    if( id->fd<0 ){
      return SQLITE_CANTOPEN; 
    }
    *pReadonly = 1;
  }else{
    *pReadonly = 0;
  }
  sqlite3OsEnterMutex();
  rc = findLockInfo(id->fd, &id->pLock, &id->pOpen);
  sqlite3OsLeaveMutex();
  if( rc ){
    close(id->fd);
    return SQLITE_NOMEM;
  }
  id->locked = 0;
  TRACE3("OPEN    %-3d %s\n", id->fd, zFilename);
  OpenCounter(+1);
  return SQLITE_OK;
}


/*
** Attempt to open a new file for exclusive access by this process.
** The file will be opened for both reading and writing.  To avoid
** a potential security problem, we do not allow the file to have
** previously existed.  Nor do we allow the file to be a symbolic
** link.
**
** If delFlag is true, then make arrangements to automatically delete
** the file when it is closed.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenExclusive(const char *zFilename, OsFile *id, int delFlag){
  int rc;
  if( access(zFilename, 0)==0 ){
    return SQLITE_CANTOPEN;
  }
  id->dirfd = -1;
  id->fd = open(zFilename,
                O_RDWR|O_CREAT|O_EXCL|O_NOFOLLOW|O_LARGEFILE|O_BINARY, 0600);
  if( id->fd<0 ){
    return SQLITE_CANTOPEN;
  }
  sqlite3OsEnterMutex();
  rc = findLockInfo(id->fd, &id->pLock, &id->pOpen);
  sqlite3OsLeaveMutex();
  if( rc ){
    close(id->fd);
    unlink(zFilename);
    return SQLITE_NOMEM;
  }
  id->locked = 0;
  if( delFlag ){
    unlink(zFilename);
  }
  TRACE3("OPEN-EX %-3d %s\n", id->fd, zFilename);
  OpenCounter(+1);
  return SQLITE_OK;
}

/*
** Attempt to open a new file for read-only access.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenReadOnly(const char *zFilename, OsFile *id){
  int rc;
  id->dirfd = -1;
  id->fd = open(zFilename, O_RDONLY|O_LARGEFILE|O_BINARY);
  if( id->fd<0 ){
    return SQLITE_CANTOPEN;
  }
  sqlite3OsEnterMutex();
  rc = findLockInfo(id->fd, &id->pLock, &id->pOpen);
  sqlite3OsLeaveMutex();
  if( rc ){
    close(id->fd);
    return SQLITE_NOMEM;
  }
  id->locked = 0;
  TRACE3("OPEN-RO %-3d %s\n", id->fd, zFilename);
  OpenCounter(+1);
  return SQLITE_OK;
}

/*
** Attempt to open a file descriptor for the directory that contains a
** file.  This file descriptor can be used to fsync() the directory
** in order to make sure the creation of a new file is actually written
** to disk.
**
** This routine is only meaningful for Unix.  It is a no-op under
** windows since windows does not support hard links.
**
** On success, a handle for a previously open file is at *id is
** updated with the new directory file descriptor and SQLITE_OK is
** returned.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id unchanged.
*/
int sqlite3OsOpenDirectory(
  const char *zDirname,
  OsFile *id
){
  if( id->fd<0 ){
    /* Do not open the directory if the corresponding file is not already
    ** open. */
    return SQLITE_CANTOPEN;
  }
  assert( id->dirfd<0 );
  id->dirfd = open(zDirname, O_RDONLY|O_BINARY, 0644);
  if( id->dirfd<0 ){
    return SQLITE_CANTOPEN; 
  }
  TRACE3("OPENDIR %-3d %s\n", id->dirfd, zDirname);
  return SQLITE_OK;
}

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at least SQLITE_TEMPNAME_SIZE characters.
*/
int sqlite3OsTempFileName(char *zBuf){
  static const char *azDirs[] = {
     "/var/tmp",
     "/usr/tmp",
     "/tmp",
     ".",
  };
  static unsigned char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  struct stat buf;
  const char *zDir = ".";
  for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); i++){
    if( stat(azDirs[i], &buf) ) continue;
    if( !S_ISDIR(buf.st_mode) ) continue;
    if( access(azDirs[i], 07) ) continue;
    zDir = azDirs[i];
    break;
  }
  do{
    sprintf(zBuf, "%s/"TEMP_FILE_PREFIX, zDir);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
  }while( access(zBuf,0)==0 );
  return SQLITE_OK; 
}

/*
** Close a file.
*/
int sqlite3OsClose(OsFile *id){
  sqlite3OsUnlock(id);
  if( id->dirfd>=0 ) close(id->dirfd);
  id->dirfd = -1;
  sqlite3OsEnterMutex();
  if( id->pOpen->nLock ){
    /* If there are outstanding locks, do not actually close the file just
    ** yet because that would clear those locks.  Instead, add the file
    ** descriptor to pOpen->aPending.  It will be automatically closed when
    ** the last lock is cleared.
    */
    int *aNew;
    struct openCnt *pOpen = id->pOpen;
    pOpen->nPending++;
    aNew = sqliteRealloc( pOpen->aPending, pOpen->nPending*sizeof(int) );
    if( aNew==0 ){
      /* If a malloc fails, just leak the file descriptor */
    }else{
      pOpen->aPending = aNew;
      pOpen->aPending[pOpen->nPending-1] = id->fd;
    }
  }else{
    /* There are no outstanding locks so we can close the file immediately */
    close(id->fd);
  }
  releaseLockInfo(id->pLock);
  releaseOpenCnt(id->pOpen);
  sqlite3OsLeaveMutex();
  TRACE2("CLOSE   %-3d\n", id->fd);
  OpenCounter(-1);
  return SQLITE_OK;
}

/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
int sqlite3OsRead(OsFile *id, void *pBuf, int amt){
  int got;
  SimulateIOError(SQLITE_IOERR);
  TIMER_START;
  got = read(id->fd, pBuf, amt);
  TIMER_END;
  TRACE4("READ    %-3d %7d %d\n", id->fd, last_page, elapse);
  SEEK(0);
  /* if( got<0 ) got = 0; */
  if( got==amt ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
int sqlite3OsWrite(OsFile *id, const void *pBuf, int amt){
  int wrote = 0;
  SimulateIOError(SQLITE_IOERR);
  TIMER_START;
  while( amt>0 && (wrote = write(id->fd, pBuf, amt))>0 ){
    amt -= wrote;
    pBuf = &((char*)pBuf)[wrote];
  }
  TIMER_END;
  TRACE4("WRITE   %-3d %7d %d\n", id->fd, last_page, elapse);
  SEEK(0);
  if( amt>0 ){
    return SQLITE_FULL;
  }
  return SQLITE_OK;
}

/*
** Move the read/write pointer in a file.
*/
int sqlite3OsSeek(OsFile *id, off_t offset){
  SEEK(offset/1024 + 1);
  lseek(id->fd, offset, SEEK_SET);
  return SQLITE_OK;
}

/*
** Make sure all writes to a particular file are committed to disk.
**
** Under Unix, also make sure that the directory entry for the file
** has been created by fsync-ing the directory that contains the file.
** If we do not do this and we encounter a power failure, the directory
** entry for the journal might not exist after we reboot.  The next
** SQLite to access the file will not know that the journal exists (because
** the directory entry for the journal was never created) and the transaction
** will not roll back - possibly leading to database corruption.
*/
int sqlite3OsSync(OsFile *id){
  SimulateIOError(SQLITE_IOERR);
  TRACE2("SYNC    %-3d\n", id->fd);
  if( fsync(id->fd) ){
    return SQLITE_IOERR;
  }else{
    if( id->dirfd>=0 ){
      TRACE2("DIRSYNC %-3d\n", id->dirfd);
      fsync(id->dirfd);
      close(id->dirfd);  /* Only need to sync once, so close the directory */
      id->dirfd = -1;    /* when we are done. */
    }
    return SQLITE_OK;
  }
}

/*
** Truncate an open file to a specified size
*/
int sqlite3OsTruncate(OsFile *id, off_t nByte){
  SimulateIOError(SQLITE_IOERR);
  return ftruncate(id->fd, nByte)==0 ? SQLITE_OK : SQLITE_IOERR;
}

/*
** Determine the current size of a file in bytes
*/
int sqlite3OsFileSize(OsFile *id, off_t *pSize){
  struct stat buf;
  SimulateIOError(SQLITE_IOERR);
  if( fstat(id->fd, &buf)!=0 ){
    return SQLITE_IOERR;
  }
  *pSize = buf.st_size;
  return SQLITE_OK;
}


/*
** Change the status of the lock on the file "id" to be a readlock.
** If the file was write locked, then this reduces the lock to a read.
** If the file was read locked, then this acquires a new read lock.
**
** Return SQLITE_OK on success and SQLITE_BUSY on failure.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsReadLock(OsFile *id){
  int rc;
  sqlite3OsEnterMutex();
  if( id->pLock->cnt>0 ){
    if( !id->locked ){
      id->pLock->cnt++;
      id->locked = 1;
      id->pOpen->nLock++;
    }
    rc = SQLITE_OK;
  }else if( id->locked || id->pLock->cnt==0 ){
    struct flock lock;
    int s;
    lock.l_type = F_RDLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start = lock.l_len = 0L;
    s = fcntl(id->fd, F_SETLK, &lock);
    if( s!=0 ){
      rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY;
    }else{
      rc = SQLITE_OK;
      if( !id->locked ){
        id->pOpen->nLock++;
        id->locked = 1;
      }
      id->pLock->cnt = 1;
    }
  }else{
    rc = SQLITE_BUSY;
  }
  sqlite3OsLeaveMutex();
  return rc;
}

/*
** Change the lock status to be an exclusive or write lock.  Return
** SQLITE_OK on success and SQLITE_BUSY on a failure.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsWriteLock(OsFile *id){
  int rc;
  sqlite3OsEnterMutex();
  if( id->pLock->cnt==0 || (id->pLock->cnt==1 && id->locked==1) ){
    struct flock lock;
    int s;
    lock.l_type = F_WRLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start = lock.l_len = 0L;
    s = fcntl(id->fd, F_SETLK, &lock);
    if( s!=0 ){
      rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY;
    }else{
      rc = SQLITE_OK;
      if( !id->locked ){
        id->pOpen->nLock++;
        id->locked = 1;
      }
      id->pLock->cnt = -1;
    }
  }else{
    rc = SQLITE_BUSY;
  }
  sqlite3OsLeaveMutex();
  return rc;
}

/*
** Unlock the given file descriptor.  If the file descriptor was
** not previously locked, then this routine is a no-op.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsUnlock(OsFile *id){
  int rc;
  if( !id->locked ) return SQLITE_OK;
  sqlite3OsEnterMutex();
  assert( id->pLock->cnt!=0 );
  if( id->pLock->cnt>1 ){
    id->pLock->cnt--;
    rc = SQLITE_OK;
  }else{
    struct flock lock;
    int s;
    lock.l_type = F_UNLCK;
    lock.l_whence = SEEK_SET;
    lock.l_start = lock.l_len = 0L;
    s = fcntl(id->fd, F_SETLK, &lock);
    if( s!=0 ){
      rc = (errno==EINVAL) ? SQLITE_NOLFS : SQLITE_BUSY;
    }else{
      rc = SQLITE_OK;
      id->pLock->cnt = 0;
    }
  }
  if( rc==SQLITE_OK ){
    /* 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.
    */
    struct openCnt *pOpen = id->pOpen;
    pOpen->nLock--;
    assert( pOpen->nLock>=0 );
    if( pOpen->nLock==0 && pOpen->nPending>0 ){
      int i;
      for(i=0; i<pOpen->nPending; i++){
        close(pOpen->aPending[i]);
      }
      sqliteFree(pOpen->aPending);
      pOpen->nPending = 0;
      pOpen->aPending = 0;
    }
  }
  sqlite3OsLeaveMutex();
  id->locked = 0;
  return rc;
}

/*
** Get information to seed the random number generator.  The seed
** is written into the buffer zBuf[256].  The calling function must
** supply a sufficiently large buffer.
*/
int sqlite3OsRandomSeed(char *zBuf){
  /* We have to initialize zBuf to prevent valgrind from reporting
  ** errors.  The reports issued by valgrind are incorrect - we would
  ** prefer that the randomness be increased by making use of the
  ** uninitialized space in zBuf - but valgrind errors tend to worry
  ** some users.  Rather than argue, it seems easier just to initialize
  ** the whole array and silence valgrind, even if that means less randomness
  ** in the random seed.
  **
  ** When testing, initializing zBuf[] to zero is all we do.  That means
  ** that we always use the same random number sequence.* This makes the
  ** tests repeatable.
  */
  memset(zBuf, 0, 256);
#if !defined(SQLITE_TEST)
  {
    int pid;
    time((time_t*)zBuf);
    pid = getpid();
    memcpy(&zBuf[sizeof(time_t)], &pid, sizeof(pid));
  }
#endif
  return SQLITE_OK;
}

/*
** Sleep for a little while.  Return the amount of time slept.
*/
int sqlite3OsSleep(int ms){
#if defined(HAVE_USLEEP) && HAVE_USLEEP
  usleep(ms*1000);
  return ms;
#else
  sleep((ms+999)/1000);
  return 1000*((ms+999)/1000);
#endif
}

/*
** Static variables used for thread synchronization
*/
static int inMutex = 0;
static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;

/*
** The following pair of routine implement mutual exclusion for
** multi-threaded processes.  Only a single thread is allowed to
** executed code that is surrounded by EnterMutex() and LeaveMutex().
**
** SQLite uses only a single Mutex.  There is not much critical
** code and what little there is executes quickly and without blocking.
*/
void sqlite3OsEnterMutex(){
#ifdef SQLITE_UNIX_THREADS
  pthread_mutex_lock(&mutex);
#endif
  assert( !inMutex );
  inMutex = 1;
}
void sqlite3OsLeaveMutex(){
  assert( inMutex );
  inMutex = 0;
#ifdef SQLITE_UNIX_THREADS
  pthread_mutex_unlock(&mutex);
#endif
}

/*
** Turn a relative pathname into a full pathname.  Return a pointer
** to the full pathname stored in space obtained from sqliteMalloc().
** The calling function is responsible for freeing this space once it
** is no longer needed.
*/
char *sqlite3OsFullPathname(const char *zRelative){
  char *zFull = 0;
  if( zRelative[0]=='/' ){
    sqlite3SetString(&zFull, zRelative, (char*)0);
  }else{
    char zBuf[5000];
    sqlite3SetString(&zFull, getcwd(zBuf, sizeof(zBuf)), "/", zRelative,
                    (char*)0);
  }
  return zFull;
}

/*
** 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 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.
*/
int sqlite3OsCurrentTime(double *prNow){
  time_t t;
  time(&t);
  *prNow = t/86400.0 + 2440587.5;
#ifdef SQLITE_TEST
  if( sqlite3_current_time ){
    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
  }
#endif
  return 0;
}

#endif /* OS_UNIX */

/*
** 2004 May 22
**
** 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 header file defined OS-specific features for Unix.
*/
#ifndef _SQLITE_OS_UNIX_H_
#define _SQLITE_OS_UNIX_H_

/*
** Helpful hint:  To get this to compile on HP/UX, add -D_INCLUDE_POSIX_SOURCE
** to the compiler command line.
*/

/*
** These #defines should enable >2GB file support on Posix if the
** underlying operating system supports it.  If the OS lacks
** large file support, or if the OS is windows, these should be no-ops.
**
** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch
** on the compiler command line.  This is necessary if you are compiling
** on a recent machine (ex: RedHat 7.2) but you want your code to work
** on an older machine (ex: RedHat 6.0).  If you compile on RedHat 7.2
** without this option, LFS is enable.  But LFS does not exist in the kernel
** in RedHat 6.0, so the code won't work.  Hence, for maximum binary
** portability you should omit LFS.
**
** Similar is true for MacOS.  LFS is only supported on MacOS 9 and later.
*/
#ifndef SQLITE_DISABLE_LFS
# define _LARGE_FILE       1
# ifndef _FILE_OFFSET_BITS
#   define _FILE_OFFSET_BITS 64
# endif
# define _LARGEFILE_SOURCE 1
#endif

/*
** standard include files.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

/*
** The OsFile structure is a operating-system independing representation
** of an open file handle.  It is defined differently for each architecture.
**
** This is the definition for Unix.
*/
typedef struct OsFile OsFile;
struct OsFile {
  struct openCnt *pOpen;    /* Info about all open fd's on this inode */
  struct lockInfo *pLock;   /* Info about locks on this inode */
  int fd;                   /* The file descriptor */
  int locked;               /* True if this instance holds the lock */
  int dirfd;                /* File descriptor for the directory */
};

/*
** Maximum number of characters in a temporary file name
*/
#define SQLITE_TEMPNAME_SIZE 200

/*
** Minimum interval supported by sqlite3OsSleep().
*/
#if defined(HAVE_USLEEP) && HAVE_USLEEP
# define SQLITE_MIN_SLEEP_MS 1
#else
# define SQLITE_MIN_SLEEP_MS 1000
#endif


#endif /* _SQLITE_OS_UNIX_H_ */

/*
** 2004 May 22
**
** 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 windows.
*/
#include "os.h"          /* Must be first to enable large file support */
#if OS_WIN               /* This file is used for windows only */
#include "sqliteInt.h"

#include <winbase.h>

/*
** Macros used to determine whether or not to use threads.
*/
#if defined(THREADSAFE) && THREADSAFE
# define SQLITE_W32_THREADS 1
#endif

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

/*
** Delete the named file
*/
int sqlite3OsDelete(const char *zFilename){
  DeleteFile(zFilename);
  return SQLITE_OK;
}

/*
** Return TRUE if the named file exists.
*/
int sqlite3OsFileExists(const char *zFilename){
  return GetFileAttributes(zFilename) != 0xffffffff;
}

/*
** Attempt to open a file for both reading and writing.  If that
** fails, try opening it read-only.  If the file does not exist,
** try to create it.
**
** On success, a handle for the open file is written to *id
** and *pReadonly is set to 0 if the file was opened for reading and
** writing or 1 if the file was opened read-only.  The function returns
** SQLITE_OK.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id and *pReadonly unchanged.
*/
int sqlite3OsOpenReadWrite(
  const char *zFilename,
  OsFile *id,
  int *pReadonly
){
  HANDLE h = CreateFile(zFilename,
     GENERIC_READ | GENERIC_WRITE,
     FILE_SHARE_READ | FILE_SHARE_WRITE,
     NULL,
     OPEN_ALWAYS,
     FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
     NULL
  );
  if( h==INVALID_HANDLE_VALUE ){
    h = CreateFile(zFilename,
       GENERIC_READ,
       FILE_SHARE_READ,
       NULL,
       OPEN_ALWAYS,
       FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
       NULL
    );
    if( h==INVALID_HANDLE_VALUE ){
      return SQLITE_CANTOPEN;
    }
    *pReadonly = 1;
  }else{
    *pReadonly = 0;
  }
  id->h = h;
  id->locked = 0;
  OpenCounter(+1);
  return SQLITE_OK;
}


/*
** Attempt to open a new file for exclusive access by this process.
** The file will be opened for both reading and writing.  To avoid
** a potential security problem, we do not allow the file to have
** previously existed.  Nor do we allow the file to be a symbolic
** link.
**
** If delFlag is true, then make arrangements to automatically delete
** the file when it is closed.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenExclusive(const char *zFilename, OsFile *id, int delFlag){
  HANDLE h;
  int fileflags;
  if( delFlag ){
    fileflags = FILE_ATTRIBUTE_TEMPORARY | FILE_FLAG_RANDOM_ACCESS 
                     | FILE_FLAG_DELETE_ON_CLOSE;
  }else{
    fileflags = FILE_FLAG_RANDOM_ACCESS;
  }
  h = CreateFile(zFilename,
     GENERIC_READ | GENERIC_WRITE,
     0,
     NULL,
     CREATE_ALWAYS,
     fileflags,
     NULL
  );
  if( h==INVALID_HANDLE_VALUE ){
    return SQLITE_CANTOPEN;
  }
  id->h = h;
  id->locked = 0;
  OpenCounter(+1);
  return SQLITE_OK;
}

/*
** Attempt to open a new file for read-only access.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3OsOpenReadOnly(const char *zFilename, OsFile *id){
  HANDLE h = CreateFile(zFilename,
     GENERIC_READ,
     0,
     NULL,
     OPEN_EXISTING,
     FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
     NULL
  );
  if( h==INVALID_HANDLE_VALUE ){
    return SQLITE_CANTOPEN;
  }
  id->h = h;
  id->locked = 0;
  OpenCounter(+1);
  return SQLITE_OK;
}

/*
** Attempt to open a file descriptor for the directory that contains a
** file.  This file descriptor can be used to fsync() the directory
** in order to make sure the creation of a new file is actually written
** to disk.
**
** This routine is only meaningful for Unix.  It is a no-op under
** windows since windows does not support hard links.
**
** On success, a handle for a previously open file is at *id is
** updated with the new directory file descriptor and SQLITE_OK is
** returned.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id unchanged.
*/
int sqlite3OsOpenDirectory(
  const char *zDirname,
  OsFile *id
){
  return SQLITE_OK;
}

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at least SQLITE_TEMPNAME_SIZE characters.
*/
int sqlite3OsTempFileName(char *zBuf){
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  char zTempPath[SQLITE_TEMPNAME_SIZE];
  GetTempPath(SQLITE_TEMPNAME_SIZE-30, zTempPath);
  for(i=strlen(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){}
  zTempPath[i] = 0;
  for(;;){
    sprintf(zBuf, "%s\\"TEMP_FILE_PREFIX, zTempPath);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
    if( !sqlite3OsFileExists(zBuf) ) break;
  }
  return SQLITE_OK; 
}

/*
** Close a file.
*/
int sqlite3OsClose(OsFile *id){
  CloseHandle(id->h);
  OpenCounter(-1);
  return SQLITE_OK;
}

/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
int sqlite3OsRead(OsFile *id, void *pBuf, int amt){
  DWORD got;
  SimulateIOError(SQLITE_IOERR);
  TRACE2("READ %d\n", last_page);
  if( !ReadFile(id->h, pBuf, amt, &got, 0) ){
    got = 0;
  }
  if( got==(DWORD)amt ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
int sqlite3OsWrite(OsFile *id, const void *pBuf, int amt){
  int rc;
  DWORD wrote;
  SimulateIOError(SQLITE_IOERR);
  TRACE2("WRITE %d\n", last_page);
  while( amt>0 && (rc = WriteFile(id->h, pBuf, amt, &wrote, 0))!=0 && wrote>0 ){
    amt -= wrote;
    pBuf = &((char*)pBuf)[wrote];
  }
  if( !rc || amt>(int)wrote ){
    return SQLITE_FULL;
  }
  return SQLITE_OK;
}

/*
** Move the read/write pointer in a file.
*/
int sqlite3OsSeek(OsFile *id, off_t offset){
  LONG upperBits = offset>>32;
  LONG lowerBits = offset & 0xffffffff;
  DWORD rc;
  SEEK(offset/1024 + 1);
  rc = SetFilePointer(id->h, lowerBits, &upperBits, FILE_BEGIN);
  /* TRACE3("SEEK rc=0x%x upper=0x%x\n", rc, upperBits); */
  return SQLITE_OK;
}

/*
** Make sure all writes to a particular file are committed to disk.
*/
int sqlite3OsSync(OsFile *id){
  if( FlushFileBuffers(id->h) ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
}

/*
** Truncate an open file to a specified size
*/
int sqlite3OsTruncate(OsFile *id, off_t nByte){
  LONG upperBits = nByte>>32;
  SimulateIOError(SQLITE_IOERR);
  SetFilePointer(id->h, nByte, &upperBits, FILE_BEGIN);
  SetEndOfFile(id->h);
  return SQLITE_OK;
}

/*
** Determine the current size of a file in bytes
*/
int sqlite3OsFileSize(OsFile *id, off_t *pSize){
  DWORD upperBits, lowerBits;
  SimulateIOError(SQLITE_IOERR);
  lowerBits = GetFileSize(id->h, &upperBits);
  *pSize = (((off_t)upperBits)<<32) + lowerBits;
  return SQLITE_OK;
}

/*
** Return true (non-zero) if we are running under WinNT, Win2K or WinXP.
** Return false (zero) for Win95, Win98, or WinME.
**
** Here is an interesting observation:  Win95, Win98, and WinME lack
** the LockFileEx() API.  But we can still statically link against that
** API as long as we don't call it win running Win95/98/ME.  A call to
** this routine is used to determine if the host is Win95/98/ME or
** WinNT/2K/XP so that we will know whether or not we can safely call
** the LockFileEx() API.
*/
int isNT(void){
  static int osType = 0;   /* 0=unknown 1=win95 2=winNT */
  if( osType==0 ){
    OSVERSIONINFO sInfo;
    sInfo.dwOSVersionInfoSize = sizeof(sInfo);
    GetVersionEx(&sInfo);
    osType = sInfo.dwPlatformId==VER_PLATFORM_WIN32_NT ? 2 : 1;
  }
  return osType==2;
}

/*
** Windows file locking notes:
**
** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because
** those functions are not available.  So we use only LockFile() and
** UnlockFile().
**
** LockFile() prevents not just writing but also reading by other processes.
** (This is a design error on the part of Windows, but there is nothing
** we can do about that.)  So the region used for locking is at the
** end of the file where it is unlikely to ever interfere with an
** actual read attempt.
**
** A database read lock is obtained by locking a single randomly-chosen 
** byte out of a specific range of bytes. The lock byte is obtained at 
** random so two separate readers can probably access the file at the 
** same time, unless they are unlucky and choose the same lock byte.
** A database write lock is obtained by locking all bytes in the range.
** There can only be one writer.
**
** A lock is obtained on the first byte of the lock range before acquiring
** either a read lock or a write lock.  This prevents two processes from
** attempting to get a lock at a same time.  The semantics of 
** sqlite3OsReadLock() require that if there is already a write lock, that
** lock is converted into a read lock atomically.  The lock on the first
** byte allows us to drop the old write lock and get the read lock without
** another process jumping into the middle and messing us up.  The same
** argument applies to sqlite3OsWriteLock().
**
** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available,
** which means we can use reader/writer locks.  When reader writer locks
** are used, the lock is placed on the same range of bytes that is used
** for probabilistic locking in Win95/98/ME.  Hence, the locking scheme
** will support two or more Win95 readers or two or more WinNT readers.
** But a single Win95 reader will lock out all WinNT readers and a single
** WinNT reader will lock out all other Win95 readers.
**
** The following #defines specify the range of bytes used for locking.
** N_LOCKBYTE is the number of bytes available for doing the locking.
** The first byte used to hold the lock while the lock is changing does
** not count toward this number.  FIRST_LOCKBYTE is the address of
** the first byte in the range of bytes used for locking.
*/
#define N_LOCKBYTE       10239
#define FIRST_LOCKBYTE   (0xffffffff - N_LOCKBYTE)

/*
** Change the status of the lock on the file "id" to be a readlock.
** If the file was write locked, then this reduces the lock to a read.
** If the file was read locked, then this acquires a new read lock.
**
** Return SQLITE_OK on success and SQLITE_BUSY on failure.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsReadLock(OsFile *id){
  int rc;
  if( id->locked>0 ){
    rc = SQLITE_OK;
  }else{
    int lk;
    int res;
    int cnt = 100;
    sqlite3Randomness(sizeof(lk), &lk);
    lk = (lk & 0x7fffffff)%N_LOCKBYTE + 1;
    while( cnt-->0 && (res = LockFile(id->h, FIRST_LOCKBYTE, 0, 1, 0))==0 ){
      Sleep(1);
    }
    if( res ){
      UnlockFile(id->h, FIRST_LOCKBYTE+1, 0, N_LOCKBYTE, 0);
      if( isNT() ){
        OVERLAPPED ovlp;
        ovlp.Offset = FIRST_LOCKBYTE+1;
        ovlp.OffsetHigh = 0;
        ovlp.hEvent = 0;
        res = LockFileEx(id->h, LOCKFILE_FAIL_IMMEDIATELY, 
                          0, N_LOCKBYTE, 0, &ovlp);
      }else{
        res = LockFile(id->h, FIRST_LOCKBYTE+lk, 0, 1, 0);
      }
      UnlockFile(id->h, FIRST_LOCKBYTE, 0, 1, 0);
    }
    if( res ){
      id->locked = lk;
      rc = SQLITE_OK;
    }else{
      rc = SQLITE_BUSY;
    }
  }
  return rc;
}

/*
** Change the lock status to be an exclusive or write lock.  Return
** SQLITE_OK on success and SQLITE_BUSY on a failure.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsWriteLock(OsFile *id){
  int rc;
  if( id->locked<0 ){
    rc = SQLITE_OK;
  }else{
    int res;
    int cnt = 100;
    while( cnt-->0 && (res = LockFile(id->h, FIRST_LOCKBYTE, 0, 1, 0))==0 ){
      Sleep(1);
    }
    if( res ){
      if( id->locked>0 ){
        if( isNT() ){
          UnlockFile(id->h, FIRST_LOCKBYTE+1, 0, N_LOCKBYTE, 0);
        }else{
          res = UnlockFile(id->h, FIRST_LOCKBYTE + id->locked, 0, 1, 0);
        }
      }
      if( res ){
        res = LockFile(id->h, FIRST_LOCKBYTE+1, 0, N_LOCKBYTE, 0);
      }else{
        res = 0;
      }
      UnlockFile(id->h, FIRST_LOCKBYTE, 0, 1, 0);
    }
    if( res ){
      id->locked = -1;
      rc = SQLITE_OK;
    }else{
      rc = SQLITE_BUSY;
    }
  }
  return rc;
}

/*
** Unlock the given file descriptor.  If the file descriptor was
** not previously locked, then this routine is a no-op.  If this
** library was compiled with large file support (LFS) but LFS is not
** available on the host, then an SQLITE_NOLFS is returned.
*/
int sqlite3OsUnlock(OsFile *id){
  int rc;
  if( id->locked==0 ){
    rc = SQLITE_OK;
  }else if( isNT() || id->locked<0 ){
    UnlockFile(id->h, FIRST_LOCKBYTE+1, 0, N_LOCKBYTE, 0);
    rc = SQLITE_OK;
    id->locked = 0;
  }else{
    UnlockFile(id->h, FIRST_LOCKBYTE+id->locked, 0, 1, 0);
    rc = SQLITE_OK;
    id->locked = 0;
  }
  return rc;
}

/*
** Get information to seed the random number generator.  The seed
** is written into the buffer zBuf[256].  The calling function must
** supply a sufficiently large buffer.
*/
int sqlite3OsRandomSeed(char *zBuf){
  /* We have to initialize zBuf to prevent valgrind from reporting
  ** errors.  The reports issued by valgrind are incorrect - we would
  ** prefer that the randomness be increased by making use of the
  ** uninitialized space in zBuf - but valgrind errors tend to worry
  ** some users.  Rather than argue, it seems easier just to initialize
  ** the whole array and silence valgrind, even if that means less randomness
  ** in the random seed.
  **
  ** When testing, initializing zBuf[] to zero is all we do.  That means
  ** that we always use the same random number sequence.* This makes the
  ** tests repeatable.
  */
  memset(zBuf, 0, 256);
  GetSystemTime((LPSYSTEMTIME)zBuf);
  return SQLITE_OK;
}

/*
** Sleep for a little while.  Return the amount of time slept.
*/
int sqlite3OsSleep(int ms){
  Sleep(ms);
  return ms;
}

/*
** Static variables used for thread synchronization
*/
static int inMutex = 0;
#ifdef SQLITE_W32_THREADS
  static CRITICAL_SECTION cs;
#endif

/*
** The following pair of routine implement mutual exclusion for
** multi-threaded processes.  Only a single thread is allowed to
** executed code that is surrounded by EnterMutex() and LeaveMutex().
**
** SQLite uses only a single Mutex.  There is not much critical
** code and what little there is executes quickly and without blocking.
*/
void sqlite3OsEnterMutex(){
#ifdef SQLITE_W32_THREADS
  static int isInit = 0;
  while( !isInit ){
    static long lock = 0;
    if( InterlockedIncrement(&lock)==1 ){
      InitializeCriticalSection(&cs);
      isInit = 1;
    }else{
      Sleep(1);
    }
  }
  EnterCriticalSection(&cs);
#endif
  assert( !inMutex );
  inMutex = 1;
}
void sqlite3OsLeaveMutex(){
  assert( inMutex );
  inMutex = 0;
#ifdef SQLITE_W32_THREADS
  LeaveCriticalSection(&cs);
#endif
}

/*
** Turn a relative pathname into a full pathname.  Return a pointer
** to the full pathname stored in space obtained from sqliteMalloc().
** The calling function is responsible for freeing this space once it
** is no longer needed.
*/
char *sqlite3OsFullPathname(const char *zRelative){
  char *zNotUsed;
  char *zFull;
  int nByte;
  nByte = GetFullPathName(zRelative, 0, 0, &zNotUsed) + 1;
  zFull = sqliteMalloc( nByte );
  if( zFull==0 ) return 0;
  GetFullPathName(zRelative, nByte, zFull, &zNotUsed);
  return zFull;
}

/*
** 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 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.
*/
int sqlite3OsCurrentTime(double *prNow){
  FILETIME ft;
  /* FILETIME structure is a 64-bit value representing the number of 
     100-nanosecond intervals since January 1, 1601 (= JD 2305813.5). 
  */
  double now;
  GetSystemTimeAsFileTime( &ft );
  now = ((double)ft.dwHighDateTime) * 4294967296.0; 
  *prNow = (now + ft.dwLowDateTime)/864000000000.0 + 2305813.5;
#ifdef SQLITE_TEST
  if( sqlite3_current_time ){
    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
  }
#endif
  return 0;
}

#endif /* OS_WIN */

/*
** 2004 May 22
**
** 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 header file defines OS-specific features for Win32
*/
#ifndef _SQLITE_OS_WIN_H_
#define _SQLITE_OS_WIN_H_

#include <windows.h>
#include <winbase.h>

#if defined(_MSC_VER) || defined(__BORLANDC__)
  typedef __int64 off_t;
#else
# if !defined(_CYGWIN_TYPES_H)
  typedef long long off_t;
#   if defined(__MINGW32__)
#     define	_OFF_T_
#   endif
# endif
#endif

/*
** The OsFile structure is a operating-system independing representation
** of an open file handle.  It is defined differently for each architecture.
**
** This is the definition for Win32.
*/
typedef struct OsFile OsFile;
struct OsFile {
  HANDLE h;               /* Handle for accessing the file */
  int locked;             /* 0: unlocked, <0: write lock, >0: read lock */
};


#define SQLITE_TEMPNAME_SIZE (MAX_PATH+50)
#define SQLITE_MIN_SLEEP_MS 1


#endif /* _SQLITE_OS_WIN_H_ */

**    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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.245 2004/05/22 03:05:34 danielk1977 Exp $
*/
#include "config.h"
#include "sqlite.h"
#include "hash.h"
#include "parse.h"
#include <stdio.h>
#include <stdlib.h>
................................................................................
typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
typedef UINT8_TYPE i8;             /* 1-byte signed integer */
typedef INTPTR_TYPE ptr;           /* Big enough to hold a pointer */
typedef unsigned INTPTR_TYPE uptr; /* Big enough to hold a pointer */









/*
** Defer sourcing vdbe.h until after the "u8" typedef is defined.
*/
#include "vdbe.h"
#include "btree.h"

/*

**    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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.246 2004/05/22 17:41:59 drh Exp $
*/
#include "config.h"
#include "sqlite.h"
#include "hash.h"
#include "parse.h"
#include <stdio.h>
#include <stdlib.h>
................................................................................
typedef UINT32_TYPE u32;           /* 4-byte unsigned integer */
typedef UINT16_TYPE u16;           /* 2-byte unsigned integer */
typedef UINT8_TYPE u8;             /* 1-byte unsigned integer */
typedef UINT8_TYPE i8;             /* 1-byte signed integer */
typedef INTPTR_TYPE ptr;           /* Big enough to hold a pointer */
typedef unsigned INTPTR_TYPE uptr; /* Big enough to hold a pointer */

/*
** Macros to determine whether the machine is big or little endian,
** evaluated at runtime.
*/
extern const int sqlite3one;
#define SQLITE3_BIGENDIAN    (*(char *)(&sqlite3one)==0)
#define SQLITE3_LITTLEENDIAN (*(char *)(&sqlite3one)==1)

/*
** Defer sourcing vdbe.h until after the "u8" typedef is defined.
*/
#include "vdbe.h"
#include "btree.h"

/*

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used to translate between UTF-8, 
** UTF-16, UTF-16BE, and UTF-16LE.
**
** $Id: utf.c,v 1.7 2004/05/22 03:05:34 danielk1977 Exp $
**
** Notes on UTF-8:
**
**   Byte-0    Byte-1    Byte-2    Byte-3    Value
**  0xxxxxxx                                 00000000 00000000 0xxxxxxx
**  110yyyyy  10xxxxxx                       00000000 00000yyy yyxxxxxx
**  1110zzzz  10yyyyyy  10xxxxxx             00000000 zzzzyyyy yyxxxxxx
................................................................................
** replacement character U+FFFD for each byte that cannot be interpeted as
** part of a valid unicode character.
**
** When converting malformed UTF-16 strings to UTF-8, one instance of the
** replacement character U+FFFD for each pair of bytes that cannot be
** interpeted as part of a valid unicode character.
*/

#include <assert.h>
#include <unistd.h>
#include "sqliteInt.h"
#include "os.h"

typedef struct UtfString UtfString;
struct UtfString {
  unsigned char *pZ;    /* Raw string data */
  int n;                /* Allocated length of pZ in bytes */
  int c;                /* Number of pZ bytes already read or written */
};
................................................................................
  }else{
    *zOut = sqlite3utf16to8(zData, nData, enc1==TEXT_Utf16be);
    if( !(*zOut) ) return SQLITE_NOMEM;
    *nOut = strlen(*zOut)+1;
  }
  return SQLITE_OK;
}
 

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used to translate between UTF-8, 
** UTF-16, UTF-16BE, and UTF-16LE.
**
** $Id: utf.c,v 1.8 2004/05/22 17:41:59 drh Exp $
**
** Notes on UTF-8:
**
**   Byte-0    Byte-1    Byte-2    Byte-3    Value
**  0xxxxxxx                                 00000000 00000000 0xxxxxxx
**  110yyyyy  10xxxxxx                       00000000 00000yyy yyxxxxxx
**  1110zzzz  10yyyyyy  10xxxxxx             00000000 zzzzyyyy yyxxxxxx
................................................................................
** replacement character U+FFFD for each byte that cannot be interpeted as
** part of a valid unicode character.
**
** When converting malformed UTF-16 strings to UTF-8, one instance of the
** replacement character U+FFFD for each pair of bytes that cannot be
** interpeted as part of a valid unicode character.
*/

#include <assert.h>

#include "sqliteInt.h"


typedef struct UtfString UtfString;
struct UtfString {
  unsigned char *pZ;    /* Raw string data */
  int n;                /* Allocated length of pZ in bytes */
  int c;                /* Number of pZ bytes already read or written */
};
................................................................................
  }else{
    *zOut = sqlite3utf16to8(zData, nData, enc1==TEXT_Utf16be);
    if( !(*zOut) ) return SQLITE_NOMEM;
    *nOut = strlen(*zOut)+1;
  }
  return SQLITE_OK;
}