** 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.
**
*************************************************************************
** $Id: btree.c,v 1.305 2006/01/20 18:10:57 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
**
**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
**     "Sorting And Searching", pages 473-480. Addison-Wesley
**     Publishing Company, Reading, Massachusetts.
................................................................................
      }
    }else{
      rc = SQLITE_NOMEM;
    }
  }
  assert( !pCur->pPage->intKey || !pCur->pKey );

  /* Todo: Should we drop the reference to pCur->pPage here? */
  releasePage(pCur->pPage);
  pCur->pPage = 0;

  if( rc==SQLITE_OK ){
    pCur->eState = CURSOR_REQUIRESEEK;
  }

  return rc;
}

/*

** 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.
**
*************************************************************************
** $Id: btree.c,v 1.306 2006/01/21 12:08:54 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
**
**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
**     "Sorting And Searching", pages 473-480. Addison-Wesley
**     Publishing Company, Reading, Massachusetts.
................................................................................
      }
    }else{
      rc = SQLITE_NOMEM;
    }
  }
  assert( !pCur->pPage->intKey || !pCur->pKey );

  if( rc==SQLITE_OK ){
    releasePage(pCur->pPage);
    pCur->pPage = 0;


    pCur->eState = CURSOR_REQUIRESEEK;
  }

  return rc;
}

/*

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.248 2006/01/20 18:10:57 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>
................................................................................
    assert( pPager->aInJournal==0 );
    assert( pPager->dirtyCache==0 || pPager->useJournal==0 );
  }
  rc = sqlite3OsUnlock(pPager->fd, SHARED_LOCK);
  pPager->state = PAGER_SHARED;
  pPager->origDbSize = 0;
  pPager->setMaster = 0;


  return rc;
}

/*
** Compute and return a checksum for the page of data.
**
** This is not a real checksum.  It is really just the sum of the 

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.249 2006/01/21 12:08:54 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>
................................................................................
    assert( pPager->aInJournal==0 );
    assert( pPager->dirtyCache==0 || pPager->useJournal==0 );
  }
  rc = sqlite3OsUnlock(pPager->fd, SHARED_LOCK);
  pPager->state = PAGER_SHARED;
  pPager->origDbSize = 0;
  pPager->setMaster = 0;
  pPager->needSync = 0;
  pPager->pFirstSynced = pPager->pFirst;
  return rc;
}

/*
** Compute and return a checksum for the page of data.
**
** This is not a real checksum.  It is really just the sum of the 

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing expressions.
#
# $Id: expr.test,v 1.49 2006/01/07 14:02:27 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Create a table to work with.
#
execsql {CREATE TABLE test1(i1 int, i2 int, r1 real, r2 real, t1 text, t2 text)}
................................................................................
test_expr expr-6.74 {t1='AC', t2='A*C'} {t1 GLOB t2} 1
test_expr expr-6.75 {t1='AC', t2='A*?C'} {t1 GLOB t2} 0

test_expr expr-6.63 {t1=NULL, t2='a*?c'} {t1 GLOB t2} {{}}
test_expr expr-6.64 {t1='ac', t2=NULL} {t1 GLOB t2} {{}}
test_expr expr-6.65 {t1=NULL, t2='a*?c'} {t1 NOT GLOB t2} {{}}
test_expr expr-6.66 {t1='ac', t2=NULL} {t1 NOT GLOB t2} {{}}








test_expr expr-case.1 {i1=1, i2=2} \
	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} ne
test_expr expr-case.2 {i1=2, i2=2} \
	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} eq
test_expr expr-case.3 {i1=NULL, i2=2} \
	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} ne

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing expressions.
#
# $Id: expr.test,v 1.50 2006/01/21 12:08:54 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Create a table to work with.
#
execsql {CREATE TABLE test1(i1 int, i2 int, r1 real, r2 real, t1 text, t2 text)}
................................................................................
test_expr expr-6.74 {t1='AC', t2='A*C'} {t1 GLOB t2} 1
test_expr expr-6.75 {t1='AC', t2='A*?C'} {t1 GLOB t2} 0

test_expr expr-6.63 {t1=NULL, t2='a*?c'} {t1 GLOB t2} {{}}
test_expr expr-6.64 {t1='ac', t2=NULL} {t1 GLOB t2} {{}}
test_expr expr-6.65 {t1=NULL, t2='a*?c'} {t1 NOT GLOB t2} {{}}
test_expr expr-6.66 {t1='ac', t2=NULL} {t1 NOT GLOB t2} {{}}

# Check that the affinity of a CAST expression is calculated correctly.
ifcapable cast {
  test_expr expr-6.67 {t1='01', t2=1} {t1 = t2} 0
  test_expr expr-6.68 {t1='1', t2=1} {t1 = t2} 1
  test_expr expr-6.69 {t1='01', t2=1} {CAST(t1 AS INTEGER) = t2} 1
}

test_expr expr-case.1 {i1=1, i2=2} \
	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} ne
test_expr expr-case.2 {i1=2, i2=2} \
	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} eq
test_expr expr-case.3 {i1=NULL, i2=2} \
	{CASE WHEN i1 = i2 THEN 'eq' ELSE 'ne' END} ne

#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing aggregate functions and the
# GROUP BY and HAVING clauses of SELECT statements.
#
# $Id: select5.test,v 1.15 2005/09/20 18:13:25 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Build some test data
#
execsql {
................................................................................
    INSERT INTO t4 VALUES(4,NULL,6);
    INSERT INTO t4 VALUES(5,NULL,NULL);
    INSERT INTO t4 VALUES(5,NULL,NULL);
    INSERT INTO t4 VALUES(6,7,8);
    SELECT max(x), count(x), y, z FROM t4 GROUP BY y, z ORDER BY 1
  }
} {1 1 2 {} 2 1 3 {} 3 1 {} 5 4 2 {} 6 5 2 {} {} 6 1 7 8}
  






finish_test

#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing aggregate functions and the
# GROUP BY and HAVING clauses of SELECT statements.
#
# $Id: select5.test,v 1.16 2006/01/21 12:08:55 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Build some test data
#
execsql {
................................................................................
    INSERT INTO t4 VALUES(4,NULL,6);
    INSERT INTO t4 VALUES(5,NULL,NULL);
    INSERT INTO t4 VALUES(5,NULL,NULL);
    INSERT INTO t4 VALUES(6,7,8);
    SELECT max(x), count(x), y, z FROM t4 GROUP BY y, z ORDER BY 1
  }
} {1 1 2 {} 2 1 3 {} 3 1 {} 5 4 2 {} 6 5 2 {} {} 6 1 7 8}

do_test select5.7.2 {
  execsql {
    SELECT count(*), count(x) as cnt FROM t4 GROUP BY y ORDER BY cnt;
  }
} {1 1 1 1 1 1 5 5}
 
finish_test

#
#***********************************************************************
#
# The focus of the tests in this file are IO errors that occur in a shared
# cache context. What happens to connection B if one connection A encounters
# an IO-error whilst reading or writing the file-system?
#
# $Id: shared_err.test,v 1.2 2006/01/20 16:32:05 danielk1977 Exp $

proc skip {args} {}


set testdir [file dirname $argv0]
source $testdir/tester.tcl
db close

ifcapable !shared_cache||!subquery {
  finish_test
  return
}
set ::enable_shared_cache [sqlite3_enable_shared_cache 1]
































































































do_ioerr_test shared_ioerr-1 -tclprep {
  sqlite3 db2 test.db
  execsql {
    PRAGMA read_uncommitted = 1;
    CREATE TABLE t1(a,b,c);
    BEGIN;
................................................................................
# This test is designed to provoke an IO error when a cursor position is
# "saved" (because another cursor is going to modify the underlying table). 
# 
do_ioerr_test shared_ioerr-3 -tclprep {
  sqlite3 db2 test.db
  execsql {
    PRAGMA read_uncommitted = 1;















































    BEGIN;
    CREATE TABLE t1(a, b, UNIQUE(a, b));
  } db2
  for {set i 0} {$i < 5} {incr i} {
    set a [string repeat $i 10]
    set b [string repeat $i 2000]
    execsql {INSERT INTO t1 VALUES($a, $b)} db2
................................................................................
  sqlite3_step $::STMT       ;# Cursor points at 0000000000
  sqlite3_step $::STMT       ;# Cursor points at 1111111111
} -tclbody {
  execsql {
    INSERT INTO t1 VALUES(6, NULL);
  }
} -cleanup {
  do_test shared_ioerr-3.$n.cleanup.1 {
    sqlite3_step $::STMT
  } {SQLITE_ROW}
  do_test shared_ioerr-3.$n.cleanup.2 {
    sqlite3_column_text $::STMT 0
  } {2222222222}
  do_test shared_ioerr-3.$n.cleanup.3 {
    sqlite3_finalize $::STMT
  } {SQLITE_OK}
# db2 eval {select * from sqlite_master}
  db2 close
}

catch {db close}
sqlite3_enable_shared_cache $::enable_shared_cache
finish_test

#
#***********************************************************************
#
# The focus of the tests in this file are IO errors that occur in a shared
# cache context. What happens to connection B if one connection A encounters
# an IO-error whilst reading or writing the file-system?
#
# $Id: shared_err.test,v 1.3 2006/01/21 12:08:55 danielk1977 Exp $

proc skip {args} {}


set testdir [file dirname $argv0]
source $testdir/tester.tcl
db close

ifcapable !shared_cache||!subquery {
  finish_test
  return
}
set ::enable_shared_cache [sqlite3_enable_shared_cache 1]


# Todo: This is a copy of the [do_malloc_test] proc in malloc.test
# It would be better if these were consolidated.

# Usage: do_malloc_test <test number> <options...>
#
# The first argument, <test number>, is an integer used to name the
# tests executed by this proc. Options are as follows:
#
#     -tclprep          TCL script to run to prepare test.
#     -sqlprep          SQL script to run to prepare test.
#     -tclbody          TCL script to run with malloc failure simulation.
#     -sqlbody          TCL script to run with malloc failure simulation.
#     -cleanup          TCL script to run after the test.
#
# This command runs a series of tests to verify SQLite's ability
# to handle an out-of-memory condition gracefully. It is assumed
# that if this condition occurs a malloc() call will return a
# NULL pointer. Linux, for example, doesn't do that by default. See
# the "BUGS" section of malloc(3).
#
# Each iteration of a loop, the TCL commands in any argument passed
# to the -tclbody switch, followed by the SQL commands in any argument
# passed to the -sqlbody switch are executed. Each iteration the
# Nth call to sqliteMalloc() is made to fail, where N is increased
# each time the loop runs starting from 1. When all commands execute
# successfully, the loop ends.
#
proc do_malloc_test {tn args} {
  array unset ::mallocopts 
  array set ::mallocopts $args

  set ::go 1
  for {set ::n 1} {$::go && $::n < 50000} {incr ::n} {
    do_test shared_malloc-$tn.$::n {

      # Remove all traces of database files test.db and test2.db from the files
      # system. Then open (empty database) "test.db" with the handle [db].
      # 
      sqlite_malloc_fail 0
      catch {db close} 
      catch {file delete -force test.db}
      catch {file delete -force test.db-journal}
      catch {file delete -force test2.db}
      catch {file delete -force test2.db-journal}
      catch {sqlite3 db test.db} 
      set ::DB [sqlite3_connection_pointer db]

      # Execute any -tclprep and -sqlprep scripts.
      #
      if {[info exists ::mallocopts(-tclprep)]} {
        eval $::mallocopts(-tclprep)
      }
      if {[info exists ::mallocopts(-sqlprep)]} {
        execsql $::mallocopts(-sqlprep)
      }

      # Now set the ${::n}th malloc() to fail and execute the -tclbody and
      # -sqlbody scripts.
      #
      sqlite_malloc_fail $::n
      set ::mallocbody {}
      if {[info exists ::mallocopts(-tclbody)]} {
        append ::mallocbody "$::mallocopts(-tclbody)\n"
      }
      if {[info exists ::mallocopts(-sqlbody)]} {
        append ::mallocbody "db eval {$::mallocopts(-sqlbody)}"
      }
      set v [catch $::mallocbody msg]

      set leftover [lindex [sqlite_malloc_stat] 2]
      if {$leftover>0} {
        if {$leftover>1} {puts "\nLeftover: $leftover\nReturn=$v  Message=$msg"}
        set ::go 0
        if {$v} {
          puts "\nError message returned: $msg"
        } else {
          set v {1 1}
        }
      } else {
        set v2 [expr {$msg=="" || $msg=="out of memory"}]
        if {!$v2} {puts "\nError message returned: $msg"}
        lappend v $v2
      }
    } {1 1}

    sqlite_malloc_fail 0
    if {[info exists ::mallocopts(-cleanup)]} {
      catch [list uplevel #0 $::mallocopts(-cleanup)] msg
    }
  }
  unset ::mallocopts
}


do_ioerr_test shared_ioerr-1 -tclprep {
  sqlite3 db2 test.db
  execsql {
    PRAGMA read_uncommitted = 1;
    CREATE TABLE t1(a,b,c);
    BEGIN;
................................................................................
# This test is designed to provoke an IO error when a cursor position is
# "saved" (because another cursor is going to modify the underlying table). 
# 
do_ioerr_test shared_ioerr-3 -tclprep {
  sqlite3 db2 test.db
  execsql {
    PRAGMA read_uncommitted = 1;
    PRAGMA cache_size = 10;
    BEGIN;
    CREATE TABLE t1(a, b, UNIQUE(a, b));
  } db2
  for {set i 0} {$i < 200} {incr i} {
    set a [string range [string repeat "[format %03d $i]." 5] 0 end-1]

    set b [string repeat $i 2000]
    execsql {INSERT INTO t1 VALUES($a, $b)} db2
  }
  execsql {COMMIT} db2
  set ::DB2 [sqlite3_connection_pointer db2]
  set ::STMT [sqlite3_prepare $::DB2 "SELECT a FROM t1 ORDER BY a" -1 DUMMY]
  sqlite3_step $::STMT       ;# Cursor points at 000.000.000.000
  sqlite3_step $::STMT       ;# Cursor points at 001.001.001.001

} -tclbody {
  execsql {
    INSERT INTO t1 VALUES('201.201.201.201.201', NULL);
  }
} -cleanup {
  do_test shared_ioerr-3.$n.cleanup.1 {
    sqlite3_step $::STMT
  } {SQLITE_ROW}
  do_test shared_ioerr-3.$n.cleanup.2 {
    sqlite3_column_text $::STMT 0
  } {002.002.002.002.002}
  do_test shared_ioerr-3.$n.cleanup.3 {
    sqlite3_finalize $::STMT
  } {SQLITE_OK}
# db2 eval {select * from sqlite_master}
  db2 close
}

# Provoke a malloc() failure when a cursor position is being saved. This
# only happens with index cursors (because they malloc() space to save the
# current key value). It does not happen with tables, because an integer
# key does not require a malloc() to store. 
#
# The library should return an SQLITE_NOMEM to the caller. The query that
# owns the cursor (the one for which the position is not saved) should
# continue unaffected.
# 
do_malloc_test 4 -tclprep {
  sqlite3 db2 test.db
  execsql {
    PRAGMA read_uncommitted = 1;
    BEGIN;
    CREATE TABLE t1(a, b, UNIQUE(a, b));
  } db2
  for {set i 0} {$i < 5} {incr i} {
    set a [string repeat $i 10]
    set b [string repeat $i 2000]
    execsql {INSERT INTO t1 VALUES($a, $b)} db2
................................................................................
  sqlite3_step $::STMT       ;# Cursor points at 0000000000
  sqlite3_step $::STMT       ;# Cursor points at 1111111111
} -tclbody {
  execsql {
    INSERT INTO t1 VALUES(6, NULL);
  }
} -cleanup {
  do_test shared_malloc-4.$::n.cleanup.1 {
    sqlite3_step $::STMT
  } {SQLITE_ROW}
  do_test shared_malloc-4.$::n.cleanup.2 {
    sqlite3_column_text $::STMT 0
  } {2222222222}
  do_test shared_malloc-4.$::n.cleanup.3 {
    sqlite3_finalize $::STMT
  } {SQLITE_OK}
# db2 eval {select * from sqlite_master}
  db2 close
}

catch {db close}
sqlite3_enable_shared_cache $::enable_shared_cache
finish_test

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements some common TCL routines used for regression
# testing the SQLite library
#
# $Id: tester.tcl,v 1.62 2006/01/17 16:10:14 danielk1977 Exp $

# Make sure tclsqlite3 was compiled correctly.  Abort now with an
# error message if not.
#
if {[sqlite3 -tcl-uses-utf]} {
  if {"\u1234"=="u1234"} {
    puts stderr "***** BUILD PROBLEM *****"
................................................................................
      do_test $testname.$n.4 {
        catch {db close}
        set ::DB [sqlite3 db test.db; sqlite3_connection_pointer db]
        cksum
      } $checksum
    }


    if {[info exists ::ioerropts(-cleanup)]} {
      catch $::ioerropts(-cleanup)
    }
  }
  set ::sqlite_io_error_pending 0
  unset ::ioerropts
}

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements some common TCL routines used for regression
# testing the SQLite library
#
# $Id: tester.tcl,v 1.63 2006/01/21 12:08:55 danielk1977 Exp $

# Make sure tclsqlite3 was compiled correctly.  Abort now with an
# error message if not.
#
if {[sqlite3 -tcl-uses-utf]} {
  if {"\u1234"=="u1234"} {
    puts stderr "***** BUILD PROBLEM *****"
................................................................................
      do_test $testname.$n.4 {
        catch {db close}
        set ::DB [sqlite3 db test.db; sqlite3_connection_pointer db]
        cksum
      } $checksum
    }

    set ::sqlite_io_error_pending 0
    if {[info exists ::ioerropts(-cleanup)]} {
      catch $::ioerropts(-cleanup)
    }
  }
  set ::sqlite_io_error_pending 0
  unset ::ioerropts
}