SQLite TEA

#! /bin/sh
# Guess values for system-dependent variables and create Makefiles.
# Generated by GNU Autoconf 2.62 for sqlite 3.6.4.
#
# Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
# 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
# This configure script is free software; the Free Software Foundation
# gives unlimited permission to copy, distribute and modify it.
## --------------------- ##
## M4sh Initialization.  ##

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

# Identity of this package.
PACKAGE_NAME='sqlite'
PACKAGE_TARNAME='sqlite'
PACKAGE_VERSION='3.6.4'
PACKAGE_STRING='sqlite 3.6.4'
PACKAGE_BUGREPORT=''

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

#
# Report the --help message.
#
if test "$ac_init_help" = "long"; then
  # Omit some internal or obsolete options to make the list less imposing.
  # This message is too long to be a string in the A/UX 3.1 sh.
  cat <<_ACEOF
\`configure' configures sqlite 3.6.4 to adapt to many kinds of systems.

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

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

Defaults for the options are specified in brackets.

  cat <<\_ACEOF
_ACEOF
fi

if test -n "$ac_init_help"; then
  case $ac_init_help in
     short | recursive ) echo "Configuration of sqlite 3.6.4:";;
   esac
  cat <<\_ACEOF

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

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

test -n "$ac_init_help" && exit $ac_status
if $ac_init_version; then
  cat <<\_ACEOF
sqlite configure 3.6.4
generated by GNU Autoconf 2.62

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

It was created by sqlite $as_me 3.6.4, which was
generated by GNU Autoconf 2.62.  Invocation command line was

  $ $0 $@

_ACEOF
exec 5>>config.log
{

exec 6>&1

# Save the log message, to keep $[0] and so on meaningful, and to
# report actual input values of CONFIG_FILES etc. instead of their
# values after options handling.
ac_log="
This file was extended by sqlite $as_me 3.6.4, which was
generated by GNU Autoconf 2.62.  Invocation command line was

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

$config_files

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

_ACEOF
cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
ac_cs_version="\\
sqlite config.status 3.6.4
configured by $0, generated by GNU Autoconf 2.62,
  with options \\"`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`\\"

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

# Set your package name and version numbers here.
#
# This initializes the environment with PACKAGE_NAME and PACKAGE_VERSION
# set as provided.  These will also be added as -D defs in your Makefile
# so you can encode the package version directly into the source files.
#-----------------------------------------------------------------------

AC_INIT([sqlite], [3.6.4])

#--------------------------------------------------------------------
# Call TEA_INIT as the first TEA_ macro to set up initial vars.
# This will define a ${TEA_PLATFORM} variable == "unix" or "windows"
# as well as PKG_LIB_FILE and PKG_STUB_LIB_FILE.
#--------------------------------------------------------------------

/******************************************************************************
** This file is an amalgamation of many separate C source files from SQLite
** version 3.6.4.  By combining all the individual C code files into this 
** single large file, the entire code can be compiled as a one translation
** unit.  This allows many compilers to do optimizations that would not be
** possible if the files were compiled separately.  Performance improvements
** of 5% are more are commonly seen when SQLite is compiled as a single
** translation unit.
**
** This file is all you need to compile SQLite.  To use SQLite in other
** programs, you need this file and the "sqlite3.h" header file that defines
** the programming interface to the SQLite library.  (If you do not have 
** the "sqlite3.h" header file at hand, you will find a copy in the first
** 6527 lines past this header comment.)  Additional code files may be
** needed if you want a wrapper to interface SQLite with your choice of
** programming language.  The code for the "sqlite3" command-line shell
** is also in a separate file.  This file contains only code for the core
** SQLite library.
**
** This amalgamation was generated on 2008-10-15 11:27:32 UTC.
*/
#define SQLITE_CORE 1
#define SQLITE_AMALGAMATION 1
#ifndef SQLITE_PRIVATE
# define SQLITE_PRIVATE static
#endif
#ifndef SQLITE_API

**    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 1.784 2008/10/13 15:35:09 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build

** on how SQLite interfaces are suppose to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
** @(#) $Id: sqlite.h.in,v 1.404 2008/10/12 00:27:54 shane Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.

** Add the ability to override 'extern'
*/
#ifndef SQLITE_EXTERN
# define SQLITE_EXTERN extern
#endif

/*
** These no-op macros are used in front of interfaces to mark those
** interfaces as either deprecated or experimental.  New applications
** should not use deprecated intrfaces - they are support for backwards
** compatibility only.  Application writers should be aware that
** experimental interfaces are subject to change in point releases.
**




** These macros used to resolve to various kinds of compiler magic that
** would generate warning messages when they were used.  But that
** compiler magic ended up generating such a flurry of bug reports

** that we have taken it all out and gone back to using simple
** noop macros.

*/



#define SQLITE_DEPRECATED



#define SQLITE_EXPERIMENTAL


/*
** Ensure these symbols were not defined by some previous header file.
*/
#ifdef SQLITE_VERSION
# undef SQLITE_VERSION
#endif

**          evaluate to a string literal that is the SQLite version
**          with which the header file is associated.
**
** {H10014} The SQLITE_VERSION_NUMBER #define shall resolve to an integer
**          with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z
**          are the major version, minor version, and release number.
*/
#define SQLITE_VERSION         "3.6.4"
#define SQLITE_VERSION_NUMBER  3006004

/*
** CAPI3REF: Run-Time Library Version Numbers {H10020} <S60100>
** KEYWORDS: sqlite3_version
**
** These features provide the same information as the [SQLITE_VERSION]
** and [SQLITE_VERSION_NUMBER] #defines in the header, but are associated

** only the default compile-time setting, not any run-time changes
** to that setting.
**
** See the [threading mode] documentation for additional information.
**
** INVARIANTS:
**
** {H10101} The [sqlite3_threadsafe()] function shall return zero if
**          and only if SQLite was compiled with mutexing code omitted.

**
** {H10102} The value returned by the [sqlite3_threadsafe()] function

**          shall remain the same across calls to [sqlite3_config()].



*/
SQLITE_API int sqlite3_threadsafe(void);

/*
** CAPI3REF: Database Connection Handle {H12000} <S40200>
** KEYWORDS: {database connection} {database connections}
**

**          C.
**
** {H12014} A call to [sqlite3_close(C)] on a [database connection] C that
**          has one or more open [prepared statements] shall fail with
**          an [SQLITE_BUSY] error code.
**
** {H12015} A call to [sqlite3_close(C)] where C is a NULL pointer shall
**          be a harmless no-op returning SQLITE_OK.
**
** {H12019} When [sqlite3_close(C)] is invoked on a [database connection] C
**          that has a pending transaction, the transaction shall be
**          rolled back.
**
** ASSUMPTIONS:
**

** of sqlite3_initialize() does any initialization.  All other calls
** are harmless no-ops.
**
** Among other things, sqlite3_initialize() shall invoke
** sqlite3_os_init().  Similarly, sqlite3_shutdown()
** shall invoke sqlite3_os_end().
**
** The sqlite3_initialize() routine returns [SQLITE_OK] on success.
** If for some reason, sqlite3_initialize() is unable to initialize
** the library (perhaps it is unable to allocate a needed resource such
** as a mutex) it returns an [error code] other than [SQLITE_OK].
**
** The sqlite3_initialize() routine is called internally by many other
** SQLite interfaces so that an application usually does not need to
** invoke sqlite3_initialize() directly.  For example, [sqlite3_open()]
** calls sqlite3_initialize() so the SQLite library will be automatically
** initialized when [sqlite3_open()] is called if it has not be initialized
** already.  However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]
** compile-time option, then the automatic calls to sqlite3_initialize()
** are omitted and the application must call sqlite3_initialize() directly
** prior to using any other SQLite interface.  For maximum portability,
** it is recommended that applications always invoke sqlite3_initialize()
** directly prior to using any other SQLite interface.  Future releases
** of SQLite may require this.  In other words, the behavior exhibited
** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the
** default behavior in some future release of SQLite.
**
** The sqlite3_os_init() routine does operating-system specific
** initialization of the SQLite library.  The sqlite3_os_end()
** routine undoes the effect of sqlite3_os_init().  Typical tasks
** performed by these routines include allocation or deallocation
** of static resources, initialization of global variables,
** setting up a default [sqlite3_vfs] module, or setting up
** a default configuration using [sqlite3_config()].
**
** The application should never invoke either sqlite3_os_init()
** or sqlite3_os_end() directly.  The application should only invoke
** sqlite3_initialize() and sqlite3_shutdown().  The sqlite3_os_init()
** interface is called automatically by sqlite3_initialize() and
** sqlite3_os_end() is called by sqlite3_shutdown().  Appropriate
** implementations for sqlite3_os_init() and sqlite3_os_end()
** are built into SQLite when it is compiled for unix, windows, or os/2.
** When built for other platforms (using the [SQLITE_OS_OTHER=1] compile-time
** option) the application must supply a suitable implementation for
** sqlite3_os_init() and sqlite3_os_end().  An application-supplied
** implementation of sqlite3_os_init() or sqlite3_os_end()
** must return [SQLITE_OK] on success and some other [error code] upon
** failure.
*/
SQLITE_API int sqlite3_initialize(void);
SQLITE_API int sqlite3_shutdown(void);
SQLITE_API int sqlite3_os_init(void);
SQLITE_API int sqlite3_os_end(void);

/*
** CAPI3REF: Configuring The SQLite Library {H14100} <S20000><S30200>
** EXPERIMENTAL
**
** The sqlite3_config() interface is used to make global configuration
** changes to SQLite in order to tune SQLite to the specific needs of
** the application.  The default configuration is recommended for most
** applications and so this routine is usually not necessary.  It is
** provided to support rare applications with unusual needs.

**
** The first argument to sqlite3_config() is an integer
** [SQLITE_CONFIG_SINGLETHREAD | configuration option] that determines
** what property of SQLite is to be configured.  Subsequent arguments
** vary depending on the [SQLITE_CONFIG_SINGLETHREAD | configuration option]
** in the first argument.
**
** When a configuration option is set, sqlite3_config() returns [SQLITE_OK].
** If the option is unknown or SQLite is unable to set the option
** then this routine returns a non-zero [error code].
**
** INVARIANTS:
**
** {H14103} A successful invocation of [sqlite3_config()] shall return
**          [SQLITE_OK].
**
** {H14106} The [sqlite3_config()] interface shall return [SQLITE_MISUSE]
**          if it is invoked in between calls to [sqlite3_initialize()] and
**          [sqlite3_shutdown()].
**
** {H14120} A successful call to [sqlite3_config]([SQLITE_CONFIG_SINGLETHREAD])
**          shall set the default [threading mode] to Single-thread.
**
** {H14123} A successful call to [sqlite3_config]([SQLITE_CONFIG_MULTITHREAD])
**          shall set the default [threading mode] to Multi-thread.
**
** {H14126} A successful call to [sqlite3_config]([SQLITE_CONFIG_SERIALIZED])
**          shall set the default [threading mode] to Serialized.
**
** {H14129} A successful call to [sqlite3_config]([SQLITE_CONFIG_MUTEX],X)
**          where X is a pointer to an initialized [sqlite3_mutex_methods]
**          object shall cause all subsequent mutex operations performed
**          by SQLite to use the mutex methods that were present in X
**          during the call to [sqlite3_config()].
**
** {H14132} A successful call to [sqlite3_config]([SQLITE_CONFIG_GETMUTEX],X)
**          where X is a pointer to an [sqlite3_mutex_methods] object 
**          shall overwrite the content of [sqlite3_mutex_methods] object
**          with the mutex methods currently in use by SQLite.
**
** {H14135} A successful call to [sqlite3_config]([SQLITE_CONFIG_MALLOC],M)
**          where M is a pointer to an initialized [sqlite3_mem_methods]
**          object shall cause all subsequent memory allocation operations
**          performed by SQLite to use the methods that were present in 
**          M during the call to [sqlite3_config()].
**
** {H14138} A successful call to [sqlite3_config]([SQLITE_CONFIG_GETMALLOC],M)
**          where M is a pointer to an [sqlite3_mem_methods] object shall
**          overwrite the content of [sqlite3_mem_methods] object with 
**          the memory allocation methods currently in use by
**          SQLite.
**
** {H14141} A successful call to [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],1)
**          shall enable the memory allocation status collection logic.
**
** {H14144} A successful call to [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],0)
**          shall disable the memory allocation status collection logic.
**
** {H14147} The memory allocation status collection logic shall be
**          enabled by default.
**
** {H14150} A successful call to [sqlite3_config]([SQLITE_CONFIG_SCRATCH],S,Z,N)
**          where Z and N are non-negative integers and 
**          S is a pointer to an aligned memory buffer not less than
**          Z*N bytes in size shall cause S to be used by the
**          [scratch memory allocator] for as many as N simulataneous
**          allocations each of size Z.
**
** {H14153} A successful call to [sqlite3_config]([SQLITE_CONFIG_SCRATCH],S,Z,N)
**          where S is a NULL pointer shall disable the
**          [scratch memory allocator].
**
** {H14156} A successful call to
**          [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],S,Z,N)
**          where Z and N are non-negative integers and 
**          S is a pointer to an aligned memory buffer not less than
**          Z*N bytes in size shall cause S to be used by the
**          [pagecache memory allocator] for as many as N simulataneous
**          allocations each of size Z.
**
** {H14159} A successful call to
**          [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],S,Z,N)
**          where S is a NULL pointer shall disable the
**          [pagecache memory allocator].
**
** {H14162} A successful call to [sqlite3_config]([SQLITE_CONFIG_HEAP],H,Z,N)
**          where Z and N are non-negative integers and 
**          H is a pointer to an aligned memory buffer not less than
**          Z bytes in size shall enable the [memsys5] memory allocator
**          and cause it to use buffer S as its memory source and to use
**          a minimum allocation size of N.
**
** {H14165} A successful call to [sqlite3_config]([SQLITE_CONFIG_HEAP],H,Z,N)
**          where H is a NULL pointer shall disable the
**          [memsys5] memory allocator.
**
** {H14168} A successful call to [sqlite3_config]([SQLITE_CONFIG_LOOKASIDE],Z,N)
**          shall cause the default [lookaside memory allocator] configuration
**          for new [database connections] to be N slots of Z bytes each.
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_config(int, ...);

/*
** CAPI3REF: Configure database connections  {H14200} <S20000>
** EXPERIMENTAL
**
** The sqlite3_db_config() interface is used to make configuration
** changes to a [database connection].  The interface is similar to
** [sqlite3_config()] except that the changes apply to a single
** [database connection] (specified in the first argument).  The
** sqlite3_db_config() interface can only be used immediately after
** the database connection is created using [sqlite3_open()],
** [sqlite3_open16()], or [sqlite3_open_v2()].  
**
** The second argument to sqlite3_db_config(D,V,...)  is the
** configuration verb - an integer code that indicates what
** aspect of the [database connection] is being configured.
** The only choice for this value is [SQLITE_DBCONFIG_LOOKASIDE].
** New verbs are likely to be added in future releases of SQLite.
** Additional arguments depend on the verb.
**
** INVARIANTS:
**
** {H14203} A call to [sqlite3_db_config(D,V,...)] shall return [SQLITE_OK]
**          if and only if the call is successful.
**
** {H14206} If one or more slots of the [lookaside memory allocator] for
**          [database connection] D are in use, then a call to
**          [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],...) shall
**          fail with an [SQLITE_BUSY] return code.
**
** {H14209} A successful call to 
**          [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],B,Z,N) where
**          D is an open [database connection] and Z and N are positive
**          integers and B is an aligned buffer at least Z*N bytes in size
**          shall cause the [lookaside memory allocator] for D to use buffer B 
**          with N slots of Z bytes each.
**
** {H14212} A successful call to 
**          [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],B,Z,N) where
**          D is an open [database connection] and Z and N are positive
**          integers and B is NULL pointer shall cause the
**          [lookaside memory allocator] for D to a obtain Z*N byte buffer
**          from the primary memory allocator and use that buffer
**          with N lookaside slots of Z bytes each.
**
** {H14215} A successful call to 
**          [sqlite3_db_config](D,[SQLITE_DBCONFIG_LOOKASIDE],B,Z,N) where
**          D is an open [database connection] and Z and N are zero shall
**          disable the [lookaside memory allocator] for D.
**
**
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_config(sqlite3*, int op, ...);

/*
** CAPI3REF: Memory Allocation Routines {H10155} <S20120>
** EXPERIMENTAL
**

** integer key called the "rowid". The rowid is always available
** as an undeclared column named ROWID, OID, or _ROWID_ as long as those
** names are not also used by explicitly declared columns. If
** the table has a column of type INTEGER PRIMARY KEY then that column
** is another alias for the rowid.
**
** This routine returns the rowid of the most recent
** successful [INSERT] into the database from the [database connection]
** in the first argument.  If no successful [INSERT]s
** have ever occurred on that database connection, zero is returned.
**
** If an [INSERT] occurs within a trigger, then the rowid of the inserted
** row is returned by this routine as long as the trigger is running.
** But once the trigger terminates, the value returned by this routine
** reverts to the last value inserted before the trigger fired.
**
** An [INSERT] that fails due to a constraint violation is not a
** successful [INSERT] and does not change the value returned by this
** routine.  Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,
** and INSERT OR ABORT make no changes to the return value of this
** routine when their insertion fails.  When INSERT OR REPLACE
** encounters a constraint violation, it does not fail.  The
** INSERT continues to completion after deleting rows that caused
** the constraint problem so INSERT OR REPLACE will always change
** the return value of this interface.
**
** For the purposes of this routine, an [INSERT] is considered to
** be successful even if it is subsequently rolled back.
**
** INVARIANTS:
**
** {H12221} The [sqlite3_last_insert_rowid()] function shall return the rowid
**          of the most recent successful [INSERT] performed on the same
**          [database connection] and within the same or higher level
**          trigger context, or zero if there have been no qualifying
**          [INSERT] statements.
**
** {H12223} The [sqlite3_last_insert_rowid()] function shall return the
**          same value when called from the same trigger context
**          immediately before and after a [ROLLBACK].
**
** ASSUMPTIONS:
**
** {A12232} If a separate thread performs a new [INSERT] on the same
**          database connection while the [sqlite3_last_insert_rowid()]
**          function is running and thus changes the last insert rowid,
**          then the value returned by [sqlite3_last_insert_rowid()] is
**          unpredictable and might not equal either the old or the new
**          last insert rowid.
*/
SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*);

/*
** CAPI3REF: Count The Number Of Rows Modified {H12240} <S10600>
**
** This function returns the number of database rows that were changed
** or inserted or deleted by the most recently completed SQL statement
** on the [database connection] specified by the first parameter.
** Only changes that are directly specified by the [INSERT], [UPDATE],
** or [DELETE] statement are counted.  Auxiliary changes caused by
** triggers are not counted. Use the [sqlite3_total_changes()] function
** to find the total number of changes including changes caused by triggers.
**
** A "row change" is a change to a single row of a single table
** caused by an INSERT, DELETE, or UPDATE statement.  Rows that
** are changed as side effects of REPLACE constraint resolution,
** rollback, ABORT processing, DROP TABLE, or by any other

** the sqlite3_changes() interface can be called to find the number of
** changes in the most recently completed INSERT, UPDATE, or DELETE
** statement within the body of the same trigger.
** However, the number returned does not include changes
** caused by subtriggers since those have their own context.
**
** SQLite implements the command "DELETE FROM table" without a WHERE clause
** by dropping and recreating the table.  Doing so is much faster than going
** through and deleting individual elements from the table.  Because of this
** optimization, the deletions in "DELETE FROM table" are not row changes and
** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()]
** functions, regardless of the number of elements that were originally
** in the table.  To get an accurate count of the number of rows deleted, use
** "DELETE FROM table WHERE 1" instead.  Or recompile using the
** [SQLITE_OMIT_TRUNCATE_OPTIMIZATION] compile-time option to disable the
** optimization on all queries.
**
** INVARIANTS:
**
** {H12241} The [sqlite3_changes()] function shall return the number of
**          row changes caused by the most recent INSERT, UPDATE,
**          or DELETE statement on the same database connection and
**          within the same or higher trigger context, or zero if there have

** SQLite implements the command "DELETE FROM table" without a WHERE clause
** by dropping and recreating the table.  (This is much faster than going
** through and deleting individual elements from the table.)  Because of this
** optimization, the deletions in "DELETE FROM table" are not row changes and
** will not be counted by the sqlite3_changes() or [sqlite3_total_changes()]
** functions, regardless of the number of elements that were originally
** in the table.  To get an accurate count of the number of rows deleted, use
** "DELETE FROM table WHERE 1" instead.   Or recompile using the
** [SQLITE_OMIT_TRUNCATE_OPTIMIZATION] compile-time option to disable the
** optimization on all queries.
**
** See also the [sqlite3_changes()] interface.
**
** INVARIANTS:
**
** {H12261} The [sqlite3_total_changes()] returns the total number
**          of row changes caused by INSERT, UPDATE, and/or DELETE

  const void *zSql,       /* SQL statement, UTF-16 encoded */
  int nByte,              /* Maximum length of zSql in bytes. */
  sqlite3_stmt **ppStmt,  /* OUT: Statement handle */
  const void **pzTail     /* OUT: Pointer to unused portion of zSql */
);

/*
** CAPI3REF: Retrieving Statement SQL {H13100} <H13000>
**
** This interface can be used to retrieve a saved copy of the original
** SQL text used to create a [prepared statement] if that statement was
** compiled using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].
**
** INVARIANTS:
**

**
** These functions are [deprecated].  In order to maintain
** backwards compatibility with older code, these functions continue 
** to be supported.  However, new applications should avoid
** the use of these functions.  To help encourage people to avoid
** using these functions, we are not going to tell you want they do.
*/
#ifndef SQLITE_OMIT_DEPRECATED
SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*);
SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*);
SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*);
SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void);
SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void);
SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);
#endif

/*
** CAPI3REF: Obtaining SQL Function Parameter Values {H15100} <S20200>
**
** The C-language implementation of SQL functions and aggregates uses
** this set of interface routines to access the parameter values on
** the function or aggregate.

** and it is possible that another thread might change the parameter
** in between the times when *pCurrent and *pHighwater are written.
**
** See also: [sqlite3_db_status()]
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag);

























/*
** CAPI3REF: Status Parameters {H17250} <H17200>
** EXPERIMENTAL
**
** These integer constants designate various run-time status parameters
** that can be returned by [sqlite3_status()].

#define SQLITE_STATUS_SCRATCH_OVERFLOW     4
#define SQLITE_STATUS_MALLOC_SIZE          5
#define SQLITE_STATUS_PARSER_STACK         6
#define SQLITE_STATUS_PAGECACHE_SIZE       7
#define SQLITE_STATUS_SCRATCH_SIZE         8

/*
** CAPI3REF: Database Connection Status {H17500} <S60200>
** EXPERIMENTAL
**
** This interface is used to retrieve runtime status information 
** about a single [database connection].  The first argument is the
** database connection object to be interrogated.  The second argument
** is the parameter to interrogate.  Currently, the only allowed value
** for the second parameter is [SQLITE_DBSTATUS_LOOKASIDE_USED].
** Additional options will likely appear in future releases of SQLite.
**
** The current value of the requested parameter is written into *pCur
** and the highest instantaneous value is written into *pHiwtr.  If
** the resetFlg is true, then the highest instantaneous value is
** reset back down to the current value.
**
** See also: [sqlite3_status()] and [sqlite3_stmt_status()].
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg);

/*
** CAPI3REF: Status Parameters for database connections {H17520} <H17500>
** EXPERIMENTAL
**
** Status verbs for [sqlite3_db_status()].
**
** <dl>
** <dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>
** <dd>This parameter returns the number of lookaside memory slots currently
** checked out.</dd>
** </dl>
*/
#define SQLITE_DBSTATUS_LOOKASIDE_USED     0


/*
** CAPI3REF: Prepared Statement Status {H17550} <S60200>
** EXPERIMENTAL
**
** Each prepared statement maintains various
** [SQLITE_STMTSTATUS_SORT | counters] that measure the number
** of times it has performed specific operations.  These counters can
** be used to monitor the performance characteristics of the prepared
** statements.  For example, if the number of table steps greatly exceeds
** the number of table searches or result rows, that would tend to indicate
** that the prepared statement is using a full table scan rather than
** an index.  
**
** This interface is used to retrieve and reset counter values from
** a [prepared statement].  The first argument is the prepared statement
** object to be interrogated.  The second argument
** is an integer code for a specific [SQLITE_STMTSTATUS_SORT | counter]
** to be interrogated. 
** The current value of the requested counter is returned.
** If the resetFlg is true, then the counter is reset to zero after this
** interface call returns.
**
** See also: [sqlite3_status()] and [sqlite3_db_status()].
*/
SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg);

/*
** CAPI3REF: Status Parameters for prepared statements {H17570} <H17550>
** EXPERIMENTAL
**
** These preprocessor macros define integer codes that name counter
** values associated with the [sqlite3_stmt_status()] interface.
** The meanings of the various counters are as follows:
**
** <dl>
** <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>
** <dd>This is the number of times that SQLite has stepped forward in
** a table as part of a full table scan.  Large numbers for this counter
** may indicate opportunities for performance improvement through 
** careful use of indices.</dd>
**
** <dt>SQLITE_STMTSTATUS_SORT</dt>
** <dd>This is the number of sort operations that have occurred.
** A non-zero value in this counter may indicate an opportunity to
** improvement performance through careful use of indices.</dd>
**
** </dl>
*/
#define SQLITE_STMTSTATUS_FULLSCAN_STEP     1
#define SQLITE_STMTSTATUS_SORT              2

/*
** Undo the hack that converts floating point types to integer for
** builds on processors without floating point support.
*/
#ifdef SQLITE_OMIT_FLOATING_POINT
# undef double
#endif

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This is the header file for the generic hash-table implemenation
** used in SQLite.
**
** $Id: hash.h,v 1.12 2008/10/10 17:41:29 drh Exp $
*/
#ifndef _SQLITE_HASH_H_
#define _SQLITE_HASH_H_

/* Forward declarations of structures. */
typedef struct Hash Hash;
typedef struct HashElem HashElem;

/* A complete hash table is an instance of the following structure.
** The internals of this structure are intended to be opaque -- client
** code should not attempt to access or modify the fields of this structure
** directly.  Change this structure only by using the routines below.
** However, many of the "procedures" and "functions" for modifying and
** accessing this structure are really macros, so we can't really make
** this structure opaque.
*/
struct Hash {

  unsigned int copyKey: 1;  /* True if copy of key made on insert */

  unsigned int htsize : 31; /* Number of buckets in the hash table */
  unsigned int count;       /* Number of entries in this table */
  HashElem *first;          /* The first element of the array */
  struct _ht {              /* the hash table */
    int count;                 /* Number of entries with this hash */
    HashElem *chain;           /* Pointer to first entry with this hash */
  } *ht;
};

/* Each element in the hash table is an instance of the following 
** structure.  All elements are stored on a single doubly-linked list.
**
** Again, this structure is intended to be opaque, but it can't really
** be opaque because it is used by macros.
*/
struct HashElem {
  HashElem *next, *prev;   /* Next and previous elements in the table */
  void *data;              /* Data associated with this element */
  void *pKey; int nKey;    /* Key associated with this element */
};

/*






















** Access routines.  To delete, insert a NULL pointer.
*/
SQLITE_PRIVATE void sqlite3HashInit(Hash*, int copyKey);
SQLITE_PRIVATE void *sqlite3HashInsert(Hash*, const void *pKey, int nKey, void *pData);
SQLITE_PRIVATE void *sqlite3HashFind(const Hash*, const void *pKey, int nKey);
SQLITE_PRIVATE HashElem *sqlite3HashFindElem(const Hash*, const void *pKey, int nKey);
SQLITE_PRIVATE void sqlite3HashClear(Hash*);

/*
** Macros for looping over all elements of a hash table.  The idiom is

#define TK_EXCEPT                         108
#define TK_INTERSECT                      109
#define TK_SELECT                         110
#define TK_DISTINCT                       111
#define TK_DOT                            112
#define TK_FROM                           113
#define TK_JOIN                           114
#define TK_INDEXED                        115
#define TK_BY                             116
#define TK_USING                          117
#define TK_ORDER                          118

#define TK_GROUP                          119
#define TK_HAVING                         120
#define TK_LIMIT                          121
#define TK_WHERE                          122
#define TK_INTO                           123
#define TK_VALUES                         124
#define TK_INTEGER                        125
#define TK_FLOAT                          126
#define TK_BLOB                           127
#define TK_REGISTER                       128
#define TK_VARIABLE                       129
#define TK_CASE                           130
#define TK_WHEN                           131
#define TK_THEN                           132
#define TK_ELSE                           133
#define TK_INDEX                          134
#define TK_ALTER                          135
#define TK_TO                             136
#define TK_ADD                            137
#define TK_COLUMNKW                       138
#define TK_TO_TEXT                        139
#define TK_TO_BLOB                        140
#define TK_TO_NUMERIC                     141
#define TK_TO_INT                         142
#define TK_TO_REAL                        143
#define TK_END_OF_FILE                    144
#define TK_ILLEGAL                        145
#define TK_SPACE                          146
#define TK_UNCLOSED_STRING                147
#define TK_FUNCTION                       148
#define TK_COLUMN                         149
#define TK_AGG_FUNCTION                   150
#define TK_AGG_COLUMN                     151
#define TK_CONST_FUNC                     152

/************** End of parse.h ***********************************************/
/************** Continuing where we left off in sqliteInt.h ******************/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

** evaluated at runtime.
*/
#ifdef SQLITE_AMALGAMATION
SQLITE_PRIVATE const int sqlite3one;
#else
SQLITE_PRIVATE const int sqlite3one;
#endif
#if defined(i386) || defined(__i386__) || defined(_M_IX86)\
                             || defined(__x86_64) || defined(__x86_64__)
# define SQLITE_BIGENDIAN    0
# define SQLITE_LITTLEENDIAN 1
# define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
#else
# define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
# define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
# define SQLITE_UTF16NATIVE (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)

** In the usually case where WSD is supported, the SQLITE_WSD and GLOBAL
** macros become no-ops and have zero performance impact.
*/
#ifdef SQLITE_OMIT_WSD
  #define SQLITE_WSD const
  #define GLOBAL(t,v) (*(t*)sqlite3_wsd_find((void*)&(v), sizeof(v)))
  #define sqlite3GlobalConfig GLOBAL(struct Sqlite3Config, sqlite3Config)
SQLITE_API   int sqlite3_wsd_init(int N, int J);
SQLITE_API   void *sqlite3_wsd_find(void *K, int L);
#else
  #define SQLITE_WSD 
  #define GLOBAL(t,v) v
  #define sqlite3GlobalConfig sqlite3Config
#endif

/*

**    May you share freely, never taking more than you give.
**
*************************************************************************
** This header file defines the interface that the sqlite B-Tree file
** subsystem.  See comments in the source code for a detailed description
** of what each interface routine does.
**
** @(#) $Id: btree.h,v 1.104 2008/10/08 17:58:49 danielk1977 Exp $
*/
#ifndef _BTREE_H_
#define _BTREE_H_

/* TODO: This definition is just included so other modules compile. It
** needs to be revisited.
*/

SQLITE_PRIVATE int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*);

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

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

#ifdef SQLITE_TEST
SQLITE_PRIVATE int sqlite3BtreeCursorInfo(BtCursor*, int*, int);
SQLITE_PRIVATE void sqlite3BtreeCursorList(Btree*);
#endif

/*

/************** Begin file opcodes.h *****************************************/
/* Automatically generated.  Do not edit */
/* See the mkopcodeh.awk script for details */
#define OP_VNext                                1
#define OP_Affinity                             2
#define OP_Column                               3
#define OP_SetCookie                            4
#define OP_Real                               126   /* same as TK_FLOAT    */
#define OP_Sequence                             5
#define OP_MoveGt                               6
#define OP_Ge                                  72   /* same as TK_GE       */
#define OP_RowKey                               7
#define OP_SCopy                                8
#define OP_Eq                                  68   /* same as TK_EQ       */
#define OP_OpenWrite                            9
#define OP_NotNull                             66   /* same as TK_NOTNULL  */
#define OP_If                                  10
#define OP_ToInt                              142   /* same as TK_TO_INT   */
#define OP_String8                             88   /* same as TK_STRING   */
#define OP_VRowid                              11
#define OP_CollSeq                             12
#define OP_OpenRead                            13
#define OP_Expire                              14
#define OP_AutoCommit                          15
#define OP_Gt                                  69   /* same as TK_GT       */

#define OP_RowData                             44
#define OP_MemMax                              45
#define OP_Or                                  60   /* same as TK_OR       */
#define OP_NotExists                           46
#define OP_Gosub                               47
#define OP_Divide                              81   /* same as TK_SLASH    */
#define OP_Integer                             48
#define OP_ToNumeric                          141   /* same as TK_TO_NUMERIC*/
#define OP_Prev                                49
#define OP_Concat                              83   /* same as TK_CONCAT   */
#define OP_BitAnd                              74   /* same as TK_BITAND   */
#define OP_VColumn                             50
#define OP_CreateTable                         51
#define OP_Last                                52
#define OP_IsNull                              65   /* same as TK_ISNULL   */

#define OP_IdxGE                               63
#define OP_IdxDelete                           64
#define OP_Vacuum                              73
#define OP_MoveLe                              84
#define OP_IfNot                               85
#define OP_DropTable                           86
#define OP_MakeRecord                          89
#define OP_ToBlob                             140   /* same as TK_TO_BLOB  */
#define OP_ResultRow                           90
#define OP_Delete                              91
#define OP_AggFinal                            92
#define OP_Compare                             93
#define OP_ShiftLeft                           76   /* same as TK_LSHIFT   */
#define OP_Goto                                94
#define OP_TableLock                           95
#define OP_FifoRead                            96
#define OP_Clear                               97
#define OP_MoveLt                              98
#define OP_Le                                  70   /* same as TK_LE       */
#define OP_VerifyCookie                        99
#define OP_AggStep                            100
#define OP_ToText                             139   /* same as TK_TO_TEXT  */
#define OP_Not                                 16   /* same as TK_NOT      */
#define OP_ToReal                             143   /* same as TK_TO_REAL  */
#define OP_SetNumColumns                      101
#define OP_Transaction                        102
#define OP_VFilter                            103
#define OP_Ne                                  67   /* same as TK_NE       */
#define OP_VDestroy                           104
#define OP_ContextPop                         105
#define OP_BitOr                               75   /* same as TK_BITOR    */

#define OP_Rewind                             119
#define OP_MoveGe                             120
#define OP_VBegin                             121
#define OP_VUpdate                            122
#define OP_IfZero                             123
#define OP_BitNot                              87   /* same as TK_BITNOT   */
#define OP_VCreate                            124
#define OP_Found                              125
#define OP_IfPos                              127
#define OP_NullRow                            128
#define OP_Jump                               129
#define OP_Permutation                        130

/* The following opcode values are never used */
#define OP_NotUsed_131                        131
#define OP_NotUsed_132                        132
#define OP_NotUsed_133                        133
#define OP_NotUsed_134                        134
#define OP_NotUsed_135                        135
#define OP_NotUsed_136                        136
#define OP_NotUsed_137                        137
#define OP_NotUsed_138                        138


/* Properties such as "out2" or "jump" that are specified in
** comments following the "case" for each opcode in the vdbe.c
** are encoded into bitvectors as follows:
*/
#define OPFLG_JUMP            0x0001  /* jump:  P2 holds jmp target */

/*  64 */ 0x00, 0x05, 0x05, 0x15, 0x15, 0x15, 0x15, 0x15,\
/*  72 */ 0x15, 0x00, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c, 0x2c,\
/*  80 */ 0x2c, 0x2c, 0x2c, 0x2c, 0x11, 0x05, 0x00, 0x04,\
/*  88 */ 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00,\
/*  96 */ 0x01, 0x00, 0x11, 0x00, 0x00, 0x00, 0x00, 0x01,\
/* 104 */ 0x00, 0x00, 0x01, 0x08, 0x00, 0x02, 0x02, 0x05,\
/* 112 */ 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x02, 0x01,\
/* 120 */ 0x11, 0x00, 0x00, 0x05, 0x00, 0x11, 0x02, 0x05,\
/* 128 */ 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
/* 136 */ 0x00, 0x00, 0x00, 0x04, 0x04, 0x04, 0x04, 0x04,\
}

/************** End of opcodes.h *********************************************/
/************** Continuing where we left off in vdbe.h ***********************/

/*
** Prototypes for the VDBE interface.  See comments on the implementation
** for a description of what each of these routines does.

**    May you share freely, never taking more than you give.
**
*************************************************************************
** This header file defines the interface that the sqlite page cache
** subsystem.  The page cache subsystem reads and writes a file a page
** at a time and provides a journal for rollback.
**
** @(#) $Id: pager.h,v 1.85 2008/09/29 11:49:48 danielk1977 Exp $
*/

#ifndef _PAGER_H_
#define _PAGER_H_

/*
** If defined as non-zero, auto-vacuum is enabled by default. Otherwise

/*
** Valid values for the second argument to sqlite3PagerJournalMode().
*/
#define PAGER_JOURNALMODE_QUERY      -1
#define PAGER_JOURNALMODE_DELETE      0   /* Commit by deleting journal file */
#define PAGER_JOURNALMODE_PERSIST     1   /* Commit by zeroing journal header */
#define PAGER_JOURNALMODE_OFF         2   /* Journal omitted.  */
#define PAGER_JOURNALMODE_TRUNCATE    3   /* Commit by truncating journal */

/*
** See source code comments for a detailed description of the following
** routines:
*/
SQLITE_PRIVATE int sqlite3PagerOpen(sqlite3_vfs *, Pager **ppPager, const char*, int,int,int);
SQLITE_PRIVATE void sqlite3PagerSetBusyhandler(Pager*, BusyHandler *pBusyHandler);
SQLITE_PRIVATE void sqlite3PagerSetReiniter(Pager*, void(*)(DbPage*));
SQLITE_PRIVATE int sqlite3PagerSetPagesize(Pager*, u16*);
SQLITE_PRIVATE int sqlite3PagerMaxPageCount(Pager*, int);
SQLITE_PRIVATE int sqlite3PagerReadFileheader(Pager*, int, unsigned char*);
SQLITE_PRIVATE void sqlite3PagerSetCachesize(Pager*, int);
SQLITE_PRIVATE int sqlite3PagerClose(Pager *pPager);
SQLITE_PRIVATE int sqlite3PagerAcquire(Pager *pPager, Pgno pgno, DbPage **ppPage, int clrFlag);
#define sqlite3PagerGet(A,B,C) sqlite3PagerAcquire(A,B,C,0)
SQLITE_PRIVATE DbPage *sqlite3PagerLookup(Pager *pPager, Pgno pgno);
SQLITE_PRIVATE int sqlite3PagerPageRefcount(DbPage*);
SQLITE_PRIVATE int sqlite3PagerRef(DbPage*);
SQLITE_PRIVATE int sqlite3PagerUnref(DbPage*);
SQLITE_PRIVATE int sqlite3PagerWrite(DbPage*);
SQLITE_PRIVATE int sqlite3PagerPagecount(Pager*, int*);
SQLITE_PRIVATE int sqlite3PagerTruncate(Pager*,Pgno);
SQLITE_PRIVATE int sqlite3PagerBegin(DbPage*, int exFlag);
SQLITE_PRIVATE int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, Pgno, int);

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This header file defines the interface that the sqlite page cache
** subsystem. 
**
** @(#) $Id: pcache.h,v 1.13 2008/10/11 17:42:29 drh Exp $
*/

#ifndef _PCACHE_H_

typedef struct PgHdr PgHdr;
typedef struct PCache PCache;

** Under memory stress, invoke xStress to try to make pages clean.
** Only clean and unpinned pages can be reclaimed.
*/
SQLITE_PRIVATE void sqlite3PcacheOpen(
  int szPage,                    /* Size of every page */
  int szExtra,                   /* Extra space associated with each page */
  int bPurgeable,                /* True if pages are on backing store */

  int (*xStress)(void*, PgHdr*), /* Call to try to make pages clean */
  void *pStress,                 /* Argument to xStress */
  PCache *pToInit                /* Preallocated space for the PCache */
);

/* Modify the page-size after the cache has been created. */
SQLITE_PRIVATE void sqlite3PcacheSetPageSize(PCache *, int);

SQLITE_PRIVATE int sqlite3PcacheClear(PCache*);

/* Return the total number of outstanding page references */
SQLITE_PRIVATE int sqlite3PcacheRefCount(PCache*);

/* Increment the reference count of an existing page */
SQLITE_PRIVATE void sqlite3PcacheRef(PgHdr*);

SQLITE_PRIVATE int sqlite3PcachePageRefcount(PgHdr*);

/* Return the total number of pages stored in the cache */
SQLITE_PRIVATE int sqlite3PcachePagecount(PCache*);

#ifdef SQLITE_CHECK_PAGES
/* Iterate through all pages currently stored in the cache. This interface
** is only available if SQLITE_CHECK_PAGES is defined when the library is 
** built.
*/
SQLITE_PRIVATE void sqlite3PcacheIterate(PCache *pCache, void (*xIter)(PgHdr *));
#endif

/* Set and get the suggested cache-size for the specified pager-cache.
**
** If no global maximum is configured, then the system attempts to limit
** the total number of pages cached by purgeable pager-caches to the sum
** of the suggested cache-sizes.
*/
SQLITE_PRIVATE int sqlite3PcacheGetCachesize(PCache *);
SQLITE_PRIVATE void sqlite3PcacheSetCachesize(PCache *, int);

#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
/* Try to return memory used by the pcache module to the main memory heap */
SQLITE_PRIVATE int sqlite3PcacheReleaseMemory(int);
#endif

#ifdef SQLITE_TEST
SQLITE_PRIVATE void sqlite3PcacheStats(int*,int*,int*,int*);
#endif

#endif /* _PCACHE_H_ */

/************** End of pcache.h **********************************************/
/************** Continuing where we left off in sqliteInt.h ******************/

/************** Include os.h in the middle of sqliteInt.h ********************/

** to all source files.  We break it out in an effort to keep the code
** better organized.
**
** NOTE:  source files should *not* #include this header file directly.
** Source files should #include the sqliteInt.h file and let that file
** include this one indirectly.
**
** $Id: mutex.h,v 1.9 2008/10/07 15:25:48 drh Exp $
*/









/*
** Figure out what version of the code to use.  The choices are
**
**   SQLITE_MUTEX_OMIT         No mutex logic.  Not even stubs.  The
**                             mutexes implemention cannot be overridden
**                             at start-time.
**
**   SQLITE_MUTEX_NOOP         For single-threaded applications.  No
**                             mutual exclusion is provided.  But this
**                             implementation can be overridden at

**                             start-time.
**
**   SQLITE_MUTEX_PTHREADS     For multi-threaded applications on Unix.
**
**   SQLITE_MUTEX_W32          For multi-threaded applications on Win32.
**
**   SQLITE_MUTEX_OS2          For multi-threaded applications on OS/2.
*/

#if !SQLITE_THREADSAFE

# define SQLITE_MUTEX_OMIT
#endif
#if SQLITE_THREADSAFE && !defined(SQLITE_MUTEX_NOOP)
#  if SQLITE_OS_UNIX
#    define SQLITE_MUTEX_PTHREADS


#  elif SQLITE_OS_WIN
#    define SQLITE_MUTEX_W32

#  elif SQLITE_OS_OS2
#    define SQLITE_MUTEX_OS2
#  else
#    define SQLITE_MUTEX_NOOP
#  endif
#endif

#ifdef SQLITE_MUTEX_OMIT
/*
** If this is a no-op implementation, implement everything as macros.
*/
#define sqlite3_mutex_alloc(X)    ((sqlite3_mutex*)8)
#define sqlite3_mutex_free(X)
#define sqlite3_mutex_enter(X)
#define sqlite3_mutex_try(X)      SQLITE_OK
#define sqlite3_mutex_leave(X)
#define sqlite3_mutex_held(X)     1
#define sqlite3_mutex_notheld(X)  1
#define sqlite3MutexAlloc(X)      ((sqlite3_mutex*)8)
#define sqlite3MutexInit()        SQLITE_OK
#define sqlite3MutexEnd()
#endif /* defined(SQLITE_OMIT_MUTEX) */



/************** End of mutex.h ***********************************************/
/************** Continuing where we left off in sqliteInt.h ******************/


/*
** Each database file to be accessed by the system is an instance

/*
** Each SQL function is defined by an instance of the following
** structure.  A pointer to this structure is stored in the sqlite.aFunc
** hash table.  When multiple functions have the same name, the hash table
** points to a linked list of these structures.
*/
struct FuncDef {
  i16 nArg;            /* Number of arguments.  -1 means unlimited */
  u8 iPrefEnc;         /* Preferred text encoding (SQLITE_UTF8, 16LE, 16BE) */

  u8 flags;            /* Some combination of SQLITE_FUNC_* */
  void *pUserData;     /* User data parameter */
  FuncDef *pNext;      /* Next function with same name */
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
  void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
  void (*xFinalize)(sqlite3_context*);                /* Aggregate finializer */
  char *zName;         /* SQL name of the function. */
  FuncDef *pHash;      /* Next with a different name but the same hash */
};

/*
** Possible values for FuncDef.flags
*/
#define SQLITE_FUNC_LIKE     0x01 /* Candidate for the LIKE optimization */
#define SQLITE_FUNC_CASE     0x02 /* Case-sensitive LIKE-type function */
#define SQLITE_FUNC_EPHEM    0x04 /* Ephermeral.  Delete with VDBE */
#define SQLITE_FUNC_NEEDCOLL 0x08 /* sqlite3GetFuncCollSeq() might be called */

/*
** The following three macros, FUNCTION(), LIKEFUNC() and AGGREGATE() are
** used to create the initializers for the FuncDef structures.
**
**   FUNCTION(zName, nArg, iArg, bNC, xFunc)
**     Used to create a scalar function definition of a function zName 

**     that accepts nArg arguments and is implemented by a call to C 
**     function likeFunc. Argument pArg is cast to a (void *) and made
**     available as the function user-data (sqlite3_user_data()). The
**     FuncDef.flags variable is set to the value passed as the flags
**     parameter.
*/
#define FUNCTION(zName, nArg, iArg, bNC, xFunc) \
  {nArg, SQLITE_UTF8, bNC*8, SQLITE_INT_TO_PTR(iArg), 0, xFunc, 0, 0, #zName}
#define STR_FUNCTION(zName, nArg, pArg, bNC, xFunc) \
  {nArg, SQLITE_UTF8, bNC*8, pArg, 0, xFunc, 0, 0, #zName}
#define LIKEFUNC(zName, nArg, arg, flags) \
  {nArg, SQLITE_UTF8, flags, (void *)arg, 0, likeFunc, 0, 0, #zName}
#define AGGREGATE(zName, nArg, arg, nc, xStep, xFinal) \
  {nArg, SQLITE_UTF8, nc*8, SQLITE_INT_TO_PTR(arg), 0, 0, xStep,xFinal, #zName}


/*
** Each SQLite module (virtual table definition) is defined by an
** instance of the following structure, stored in the sqlite3.aModule
** hash table.
*/

    Select *pSelect;  /* A SELECT statement used in place of a table name */
    u8 isPopulated;   /* Temporary table associated with SELECT is populated */
    u8 jointype;      /* Type of join between this able and the previous */
    int iCursor;      /* The VDBE cursor number used to access this table */
    Expr *pOn;        /* The ON clause of a join */
    IdList *pUsing;   /* The USING clause of a join */
    Bitmask colUsed;  /* Bit N (1<<N) set if column N or pTab is used */
    u8 notIndexed;    /* True if there is a NOT INDEXED clause */
    char *zIndex;     /* Identifier from "INDEXED BY <zIndex>" clause */
    Index *pIndex;    /* Index structure corresponding to zIndex, if any */
  } a[1];             /* One entry for each identifier on the list */
};

/*
** Permitted values of the SrcList.a.jointype field
*/
#define JT_INNER     0x0001    /* Any kind of inner or cross join */

  Index *pIdx;          /* Index used.  NULL if no index */
  int iTabCur;          /* The VDBE cursor used to access the table */
  int iIdxCur;          /* The VDBE cursor used to acesss pIdx */
  int brk;              /* Jump here to break out of the loop */
  int nxt;              /* Jump here to start the next IN combination */
  int cont;             /* Jump here to continue with the next loop cycle */
  int top;              /* First instruction of interior of the loop */
  int op, p1, p2, p5;   /* Opcode used to terminate the loop */
  int nEq;              /* Number of == or IN constraints on this loop */
  int nIn;              /* Number of IN operators constraining this loop */
  struct InLoop {
    int iCur;              /* The VDBE cursor used by this IN operator */
    int topAddr;           /* Top of the IN loop */
  } *aInLoop;           /* Information about each nested IN operator */
  sqlite3_index_info *pBestIdx;  /* Index information for this level */

SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetDefault(void);
SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys5(void);
SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys3(void);
SQLITE_PRIVATE const sqlite3_mem_methods *sqlite3MemGetMemsys6(void);
SQLITE_PRIVATE void sqlite3BenignMallocHooks(void (*)(void), void (*)(void));
SQLITE_PRIVATE int sqlite3MemoryAlarm(void (*)(void*, sqlite3_int64, int), void*, sqlite3_int64);

#ifndef SQLITE_MUTEX_OMIT
SQLITE_PRIVATE   sqlite3_mutex_methods *sqlite3DefaultMutex(void);
SQLITE_PRIVATE   sqlite3_mutex *sqlite3MutexAlloc(int);
SQLITE_PRIVATE   int sqlite3MutexInit(void);
SQLITE_PRIVATE   int sqlite3MutexEnd(void);
#endif

SQLITE_PRIVATE int sqlite3StatusValue(int);

SQLITE_PRIVATE Expr *sqlite3Expr(sqlite3*, int, Expr*, Expr*, const Token*);
SQLITE_PRIVATE Expr *sqlite3PExpr(Parse*, int, Expr*, Expr*, const Token*);
SQLITE_PRIVATE Expr *sqlite3RegisterExpr(Parse*,Token*);
SQLITE_PRIVATE Expr *sqlite3ExprAnd(sqlite3*,Expr*, Expr*);
SQLITE_PRIVATE void sqlite3ExprSpan(Expr*,Token*,Token*);
SQLITE_PRIVATE Expr *sqlite3ExprFunction(Parse*,ExprList*, Token*);
SQLITE_PRIVATE void sqlite3ExprAssignVarNumber(Parse*, Expr*);
SQLITE_PRIVATE void sqlite3ExprClear(sqlite3*, Expr*);
SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3*, Expr*);
SQLITE_PRIVATE ExprList *sqlite3ExprListAppend(Parse*,ExprList*,Expr*,Token*);
SQLITE_PRIVATE void sqlite3ExprListDelete(sqlite3*, ExprList*);
SQLITE_PRIVATE int sqlite3Init(sqlite3*, char**);
SQLITE_PRIVATE int sqlite3InitCallback(void*, int, char**, char**);
SQLITE_PRIVATE void sqlite3Pragma(Parse*,Token*,Token*,Token*,int);
SQLITE_PRIVATE void sqlite3ResetInternalSchema(sqlite3*, int);

SQLITE_PRIVATE void sqlite3DropTable(Parse*, SrcList*, int, int);
SQLITE_PRIVATE void sqlite3DeleteTable(Table*);
SQLITE_PRIVATE void sqlite3Insert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
SQLITE_PRIVATE void *sqlite3ArrayAllocate(sqlite3*,void*,int,int,int*,int*,int*);
SQLITE_PRIVATE IdList *sqlite3IdListAppend(sqlite3*, IdList*, Token*);
SQLITE_PRIVATE int sqlite3IdListIndex(IdList*,const char*);
SQLITE_PRIVATE SrcList *sqlite3SrcListAppend(sqlite3*, SrcList*, Token*, Token*);
SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(Parse*, SrcList*, Token*, Token*,
                                      Token*, Select*, Expr*, IdList*);
SQLITE_PRIVATE void sqlite3SrcListIndexedBy(Parse *, SrcList *, Token *);
SQLITE_PRIVATE int sqlite3IndexedByLookup(Parse *, struct SrcList_item *);
SQLITE_PRIVATE void sqlite3SrcListShiftJoinType(SrcList*);
SQLITE_PRIVATE void sqlite3SrcListAssignCursors(Parse*, SrcList*);
SQLITE_PRIVATE void sqlite3IdListDelete(sqlite3*, IdList*);
SQLITE_PRIVATE void sqlite3SrcListDelete(sqlite3*, SrcList*);
SQLITE_PRIVATE void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                        Token*, int, int);
SQLITE_PRIVATE void sqlite3DropIndex(Parse*, SrcList*, int);
SQLITE_PRIVATE int sqlite3Select(Parse*, Select*, SelectDest*);
SQLITE_PRIVATE Select *sqlite3SelectNew(Parse*,ExprList*,SrcList*,Expr*,ExprList*,
                         Expr*,ExprList*,int,Expr*,Expr*);
SQLITE_PRIVATE void sqlite3SelectDelete(sqlite3*, Select*);
SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse*, SrcList*);
SQLITE_PRIVATE int sqlite3IsReadOnly(Parse*, Table*, int);
SQLITE_PRIVATE void sqlite3OpenTable(Parse*, int iCur, int iDb, Table*, int);
#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
SQLITE_PRIVATE Expr *sqlite3LimitWhere(Parse *, SrcList *, Expr *, ExprList *, Expr *, Expr *, char *);
#endif
SQLITE_PRIVATE void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
SQLITE_PRIVATE void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(Parse*, SrcList*, Expr*, ExprList**, u8);
SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo*);
SQLITE_PRIVATE int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, int);
SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse*, int, int, int);
SQLITE_PRIVATE void sqlite3ExprCodeCopy(Parse*, int, int, int);

SQLITE_PRIVATE void sqlite3RootPageMoved(Db*, int, int);
SQLITE_PRIVATE void sqlite3Reindex(Parse*, Token*, Token*);
SQLITE_PRIVATE void sqlite3AlterFunctions(sqlite3*);
SQLITE_PRIVATE void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
SQLITE_PRIVATE int sqlite3GetToken(const unsigned char *, int *);
SQLITE_PRIVATE void sqlite3NestedParse(Parse*, const char*, ...);
SQLITE_PRIVATE void sqlite3ExpirePreparedStatements(sqlite3*);
SQLITE_PRIVATE void sqlite3CodeSubselect(Parse *, Expr *, int, int);
SQLITE_PRIVATE void sqlite3SelectPrep(Parse*, Select*, NameContext*);
SQLITE_PRIVATE int sqlite3ResolveExprNames(NameContext*, Expr*);
SQLITE_PRIVATE void sqlite3ResolveSelectNames(Parse*, Select*, NameContext*);
SQLITE_PRIVATE int sqlite3ResolveOrderGroupBy(Parse*, Select*, ExprList*, const char*);
SQLITE_PRIVATE void sqlite3ColumnDefault(Vdbe *, Table *, int);
SQLITE_PRIVATE void sqlite3AlterFinishAddColumn(Parse *, Token *);
SQLITE_PRIVATE void sqlite3AlterBeginAddColumn(Parse *, SrcList *);

** This file contains the C functions that implement date and time
** functions for SQLite.  
**
** There is only one exported symbol in this file - the function
** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: date.c,v 1.92 2008/10/13 15:35:09 drh Exp $
**
** SQLite processes all times and dates as Julian Day numbers.  The
** dates and times are stored as the number of days since noon
** in Greenwich on November 24, 4714 B.C. according to the Gregorian
** calendar system. 
**
** 1970-01-01 00:00:00 is JD 2440587.5

      if( strcmp(z, "unixepoch")==0 && p->validJD ){
        p->iJD = p->iJD/86400.0 + 2440587.5*86400000.0;
        clearYMD_HMS_TZ(p);
        rc = 0;
      }
#ifndef SQLITE_OMIT_LOCALTIME
      else if( strcmp(z, "utc")==0 ){
        int c1;
        computeJD(p);
        c1 = localtimeOffset(p);
        p->iJD -= c1;
        clearYMD_HMS_TZ(p);
        p->iJD += c1 - localtimeOffset(p);
        rc = 0;
      }

    FUNCTION(time,             -1, 0, 0, timeFunc      ),
    FUNCTION(datetime,         -1, 0, 0, datetimeFunc  ),
    FUNCTION(strftime,         -1, 0, 0, strftimeFunc  ),
    FUNCTION(current_time,      0, 0, 0, ctimeFunc     ),
    FUNCTION(current_timestamp, 0, 0, 0, ctimestampFunc),
    FUNCTION(current_date,      0, 0, 0, cdateFunc     ),
#else
    STR_FUNCTION(current_time,      0, "%H:%M:%S",          0, currentTimeFunc),
    STR_FUNCTION(current_timestamp, 0, "%Y-%m-%d",          0, currentTimeFunc),
    STR_FUNCTION(current_date,      0, "%Y-%m-%d %H:%M:%S", 0, currentTimeFunc),
#endif
  };
  int i;
  FuncDefHash *pHash = &GLOBAL(FuncDefHash, sqlite3GlobalFunctions);
  FuncDef *aFunc = (FuncDef*)&GLOBAL(FuncDef, aDateTimeFuncs);

  for(i=0; i<ArraySize(aDateTimeFuncs); i++){

**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains OS interface code that is common to all
** architectures.
**
** $Id: os.c,v 1.124 2008/10/07 15:25:48 drh Exp $
*/
#define _SQLITE_OS_C_ 1
#undef _SQLITE_OS_C_

/*
** The default SQLite sqlite3_vfs implementations do not allocate
** memory (actually, os_unix.c allocates a small amount of memory

**     sqlite3OsOpen()
**     sqlite3OsRead()
**     sqlite3OsWrite()
**     sqlite3OsSync()
**     sqlite3OsLock()
**
*/
#if defined(SQLITE_TEST) && (SQLITE_OS_WIN==0)
  #define DO_OS_MALLOC_TEST if (1) {            \
    void *pTstAlloc = sqlite3Malloc(10);       \
    if (!pTstAlloc) return SQLITE_IOERR_NOMEM;  \
    sqlite3_free(pTstAlloc);                    \
  }
#else
  #define DO_OS_MALLOC_TEST

/*
** Locate a VFS by name.  If no name is given, simply return the
** first VFS on the list.
*/
SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfs){
  sqlite3_vfs *pVfs = 0;
#if SQLITE_THREADSAFE
  sqlite3_mutex *mutex;
#endif
#ifndef SQLITE_OMIT_AUTOINIT
  int rc = sqlite3_initialize();
  if( rc ) return 0;
#endif
#if SQLITE_THREADSAFE
  mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
#endif
  sqlite3_mutex_enter(mutex);
  for(pVfs = vfsList; pVfs; pVfs=pVfs->pNext){
    if( zVfs==0 ) break;
    if( strcmp(zVfs, pVfs->zName)==0 ) break;
  }

  return SQLITE_OK;
}

/*
** Unregister a VFS so that it is no longer accessible.
*/
SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs *pVfs){
#if SQLITE_THREADSAFE
  sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
#endif
  sqlite3_mutex_enter(mutex);
  vfsUnlink(pVfs);
  sqlite3_mutex_leave(mutex);
  return SQLITE_OK;
}

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement mutexes.
**





** This file contains code that is common across all mutex implementations.

**
** $Id: mutex.c,v 1.29 2008/10/07 15:25:48 drh Exp $
*/

#ifndef SQLITE_MUTEX_OMIT
/*
** Initialize the mutex system.
*/
SQLITE_PRIVATE int sqlite3MutexInit(void){ 
  int rc = SQLITE_OK;
  if( sqlite3GlobalConfig.bCoreMutex ){
    if( !sqlite3GlobalConfig.mutex.xMutexAlloc ){

  return p==0 || sqlite3GlobalConfig.mutex.xMutexHeld(p);
}
SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex *p){
  return p==0 || sqlite3GlobalConfig.mutex.xMutexNotheld(p);
}
#endif

#endif /* SQLITE_OMIT_MUTEX */

/************** End of mutex.c ***********************************************/
/************** Begin file mutex_noop.c **************************************/
/*
** 2008 October 07
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement mutexes.
**
** This implementation in this file does not provide any mutual
** exclusion and is thus suitable for use only in applications
** that use SQLite in a single thread.  The routines defined
** here are place-holders.  Applications can substitute working
** mutex routines at start-time using the
**
**     sqlite3_config(SQLITE_CONFIG_MUTEX,...)
**
** interface.
**
** If compiled with SQLITE_DEBUG, then additional logic is inserted
** that does error checking on mutexes to make sure they are being
** called correctly.
**
** $Id: mutex_noop.c,v 1.1 2008/10/07 15:25:48 drh Exp $
*/


#if defined(SQLITE_MUTEX_NOOP) && !defined(SQLITE_DEBUG)
/*
** Stub routines for all mutex methods.
**
** This routines provide no mutual exclusion or error checking.
*/
static int noopMutexHeld(sqlite3_mutex *p){ return 1; }
static int noopMutexNotheld(sqlite3_mutex *p){ return 1; }
static int noopMutexInit(void){ return SQLITE_OK; }
static int noopMutexEnd(void){ return SQLITE_OK; }
static sqlite3_mutex *noopMutexAlloc(int id){ return (sqlite3_mutex*)8; }
static void noopMutexFree(sqlite3_mutex *p){ return; }
static void noopMutexEnter(sqlite3_mutex *p){ return; }
static int noopMutexTry(sqlite3_mutex *p){ return SQLITE_OK; }
static void debugMutexLeave(sqlite3_mutex *p){ return; }

SQLITE_PRIVATE sqlite3_mutex_methods *sqlite3DefaultMutex(void){
  static sqlite3_mutex_methods sMutex = {
    noopMutexInit,
    noopMutexEnd,
    noopMutexAlloc,
    noopMutexFree,
    noopMutexEnter,
    noopMutexTry,
    noopMutexLeave,

    noopMutexHeld,
    noopMutexNotheld
  };

  return &sMutex;
}
#endif /* defined(SQLITE_MUTEX_NOOP) && !defined(SQLITE_DEBUG) */

#if defined(SQLITE_MUTEX_NOOP) && defined(SQLITE_DEBUG)
/*
** In this implementation, error checking is provided for testing
** and debugging purposes.  The mutexes still do not provide any
** mutual exclusion.
*/

/*
** The mutex object
*/
struct sqlite3_mutex {
  int id;     /* The mutex type */
  int cnt;    /* Number of entries without a matching leave */
};

/*
** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routine are
** intended for use inside assert() statements.
*/
static int debugMutexHeld(sqlite3_mutex *p){
  return p==0 || p->cnt>0;
}
static int debugMutexNotheld(sqlite3_mutex *p){
  return p==0 || p->cnt==0;
}

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

/*
** The sqlite3_mutex_alloc() routine allocates a new
** mutex and returns a pointer to it.  If it returns NULL
** that means that a mutex could not be allocated. 
*/
static sqlite3_mutex *debugMutexAlloc(int id){
  static sqlite3_mutex aStatic[6];
  sqlite3_mutex *pNew = 0;
  switch( id ){
    case SQLITE_MUTEX_FAST:
    case SQLITE_MUTEX_RECURSIVE: {
      pNew = sqlite3Malloc(sizeof(*pNew));
      if( pNew ){

  }
  return pNew;
}

/*
** This routine deallocates a previously allocated mutex.
*/
static void debugMutexFree(sqlite3_mutex *p){
  assert( p->cnt==0 );
  assert( p->id==SQLITE_MUTEX_FAST || p->id==SQLITE_MUTEX_RECURSIVE );
  sqlite3_free(p);
}

/*
** The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt
** to enter a mutex.  If another thread is already within the mutex,
** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return
** SQLITE_BUSY.  The sqlite3_mutex_try() interface returns SQLITE_OK
** upon successful entry.  Mutexes created using SQLITE_MUTEX_RECURSIVE can
** be entered multiple times by the same thread.  In such cases the,
** mutex must be exited an equal number of times before another thread
** can enter.  If the same thread tries to enter any other kind of mutex
** more than once, the behavior is undefined.
*/
static void debugMutexEnter(sqlite3_mutex *p){
  assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(p) );
  p->cnt++;
}
static int debugMutexTry(sqlite3_mutex *p){
  assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(p) );
  p->cnt++;
  return SQLITE_OK;
}

/*
** The sqlite3_mutex_leave() routine exits a mutex that was
** previously entered by the same thread.  The behavior
** is undefined if the mutex is not currently entered or
** is not currently allocated.  SQLite will never do either.
*/
static void debugMutexLeave(sqlite3_mutex *p){
  assert( debugMutexHeld(p) );
  p->cnt--;
  assert( p->id==SQLITE_MUTEX_RECURSIVE || debugMutexNotheld(p) );
}

SQLITE_PRIVATE sqlite3_mutex_methods *sqlite3DefaultMutex(void){
  static sqlite3_mutex_methods sMutex = {
    debugMutexInit,
    debugMutexEnd,
    debugMutexAlloc,
    debugMutexFree,
    debugMutexEnter,
    debugMutexTry,
    debugMutexLeave,

    debugMutexHeld,
    debugMutexNotheld
  };

  return &sMutex;
}
#endif /* defined(SQLITE_MUTEX_NOOP) && defined(SQLITE_DEBUG) */

/************** End of mutex_noop.c ******************************************/
/************** Begin file mutex_os2.c ***************************************/
/*
** 2007 August 28
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** Memory allocation functions used throughout sqlite.
**
** $Id: malloc.c,v 1.45 2008/10/12 00:27:53 shane Exp $
*/

/*
** This routine runs when the memory allocator sees that the
** total memory allocation is about to exceed the soft heap
** limit.
*/

  mem0.alarmCallback = xCallback;
  mem0.alarmArg = pArg;
  mem0.alarmThreshold = iThreshold;
  sqlite3_mutex_leave(mem0.mutex);
  return SQLITE_OK;
}

#ifndef SQLITE_OMIT_DEPRECATED
/*
** Deprecated external interface.  Internal/core SQLite code
** should call sqlite3MemoryAlarm.
*/
SQLITE_API int sqlite3_memory_alarm(
  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
  void *pArg,
  sqlite3_int64 iThreshold
){
  return sqlite3MemoryAlarm(xCallback, pArg, iThreshold);
}
#endif

/*
** Trigger the alarm 
*/
static void sqlite3MallocAlarm(int nByte){
  void (*xCallback)(void*,sqlite3_int64,int);
  sqlite3_int64 nowUsed;

  }
}
#endif

/*
** TRUE if p is a lookaside memory allocation from db
*/
#ifndef SQLITE_OMIT_LOOKASIDE
static int isLookaside(sqlite3 *db, void *p){
  return db && p && p>=db->lookaside.pStart && p<db->lookaside.pEnd;
}
#else
#define isLookaside(A,B) 0
#endif

/*
** Return the size of a memory allocation previously obtained from
** sqlite3Malloc() or sqlite3_malloc().
*/
SQLITE_PRIVATE int sqlite3MallocSize(void *p){
  return sqlite3GlobalConfig.m.xSize(p);

  }
  return p;
}

/*
** Allocate and zero memory.  If the allocation fails, make
** the mallocFailed flag in the connection pointer.
**
** If db!=0 and db->mallocFailed is true (indicating a prior malloc
** failure on the same database connection) then always return 0.
** Hence for a particular database connection, once malloc starts
** failing, it fails consistently until mallocFailed is reset.
** This is an important assumption.  There are many places in the
** code that do things like this:
**
**         int *a = (int*)sqlite3DbMallocRaw(db, 100);
**         int *b = (int*)sqlite3DbMallocRaw(db, 200);
**         if( b ) a[10] = 9;
**
** In other words, if a subsequent malloc (ex: "b") worked, it is assumed
** that all prior mallocs (ex: "a") worked too.
*/
SQLITE_PRIVATE void *sqlite3DbMallocRaw(sqlite3 *db, int n){
  void *p;
#ifndef SQLITE_OMIT_LOOKASIDE
  if( db ){
    LookasideSlot *pBuf;
    if( db->mallocFailed ){
      return 0;
    }
    if( db->lookaside.bEnabled && n<=db->lookaside.sz
         && (pBuf = db->lookaside.pFree)!=0 ){
      db->lookaside.pFree = pBuf->pNext;
      db->lookaside.nOut++;
      if( db->lookaside.nOut>db->lookaside.mxOut ){
        db->lookaside.mxOut = db->lookaside.nOut;
      }
      return (void*)pBuf;
    }
  }
#else
  if( db && db->mallocFailed ){
    return 0;
  }
#endif
  p = sqlite3Malloc(n);
  if( !p && db ){
    db->mallocFailed = 1;
  }
  return p;
}

*/
SQLITE_PRIVATE int sqlite3ApiExit(sqlite3* db, int rc){
  /* If the db handle is not NULL, then we must hold the connection handle
  ** mutex here. Otherwise the read (and possible write) of db->mallocFailed 
  ** is unsafe, as is the call to sqlite3Error().
  */
  assert( !db || sqlite3_mutex_held(db->mutex) );
  if( db && (db->mallocFailed || rc==SQLITE_IOERR_NOMEM) ){
    sqlite3Error(db, SQLITE_NOMEM, 0);
    db->mallocFailed = 0;
    rc = SQLITE_NOMEM;
  }
  return rc & (db ? db->errMask : 0xff);
}

*************************************************************************
** This file contains code to implement a pseudo-random number
** generator (PRNG) for SQLite.
**
** Random numbers are used by some of the database backends in order
** to generate random integer keys for tables or random filenames.
**
** $Id: random.c,v 1.27 2008/10/07 15:25:48 drh Exp $
*/


/* All threads share a single random number generator.
** This structure is the current state of the generator.
*/
static SQLITE_WSD struct sqlite3PrngType {

}

/*
** Return N random bytes.
*/
SQLITE_API void sqlite3_randomness(int N, void *pBuf){
  unsigned char *zBuf = pBuf;
#if SQLITE_THREADSAFE
  sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_PRNG);
#endif
  sqlite3_mutex_enter(mutex);
  while( N-- ){
    *(zBuf++) = randomByte();
  }
  sqlite3_mutex_leave(mutex);

*************************************************************************
** This is the header file for information that is private to the
** VDBE.  This information used to all be at the top of the single
** source code file "vdbe.c".  When that file became too big (over
** 6000 lines long) it was split up into several smaller files and
** this header information was factored out.
**
** $Id: vdbeInt.h,v 1.155 2008/10/07 23:46:38 drh Exp $
*/
#ifndef _VDBEINT_H_
#define _VDBEINT_H_

/*
** intToKey() and keyToInt() used to transform the rowid.  But with
** the latest versions of the design they are no-ops.

  u8 expired;             /* True if the VM needs to be recompiled */
  u8 minWriteFileFormat;  /* Minimum file format for writable database files */
  u8 inVtabMethod;        /* See comments above */
  int nChange;            /* Number of db changes made since last reset */
  i64 startTime;          /* Time when query started - used for profiling */
  int btreeMask;          /* Bitmask of db->aDb[] entries referenced */
  BtreeMutexArray aMutex; /* An array of Btree used here and needing locks */
  int aCounter[2];        /* Counters used by sqlite3_stmt_status() */
  int nSql;             /* Number of bytes in zSql */
  char *zSql;           /* Text of the SQL statement that generated this */
#ifdef SQLITE_DEBUG
  FILE *trace;          /* Write an execution trace here, if not NULL */
#endif
  int openedStatement;  /* True if this VM has opened a statement journal */
#ifdef SQLITE_SSE
  int fetchId;          /* Statement number used by sqlite3_fetch_statement */
  int lru;              /* Counter used for LRU cache replacement */
#endif
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This is the implementation of generic hash-tables
** used in SQLite.
**
** $Id: hash.c,v 1.31 2008/10/10 17:41:29 drh Exp $
*/

/* Turn bulk memory into a hash table object by initializing the
** fields of the Hash structure.
**
** "pNew" is a pointer to the hash table that is to be initialized.



** "copyKey" is true if the hash table should make its own private
** copy of keys and false if it should just use the supplied pointer.


*/
SQLITE_PRIVATE void sqlite3HashInit(Hash *pNew, int copyKey){
  assert( pNew!=0 );





  pNew->copyKey = copyKey!=0;
  pNew->first = 0;
  pNew->count = 0;
  pNew->htsize = 0;
  pNew->ht = 0;
}

/* Remove all entries from a hash table.  Reclaim all memory.

    }
    sqlite3_free(elem);
    elem = next_elem;
  }
  pH->count = 0;
}




























/*
** Hash and comparison functions when the mode is SQLITE_HASH_STRING
*/
static int strHash(const void *pKey, int nKey){
  const char *z = (const char *)pKey;
  int h = 0;
  if( nKey<=0 ) nKey = strlen(z);
  while( nKey > 0  ){
    h = (h<<3) ^ h ^ sqlite3UpperToLower[(unsigned char)*z++];
    nKey--;
  }
  return h & 0x7fffffff;
}
static int strCompare(const void *pKey1, int n1, const void *pKey2, int n2){
  if( n1!=n2 ) return 1;
  return sqlite3StrNICmp((const char*)pKey1,(const char*)pKey2,n1);
}











































































/* Link an element into the hash table
*/
static void insertElement(
  Hash *pH,              /* The complete hash table */
  struct _ht *pEntry,    /* The entry into which pNew is inserted */
  HashElem *pNew         /* The element to be inserted */

/* Resize the hash table so that it cantains "new_size" buckets.
** "new_size" must be a power of 2.  The hash table might fail 
** to resize if sqlite3_malloc() fails.
*/
static void rehash(Hash *pH, int new_size){
  struct _ht *new_ht;            /* The new hash table */
  HashElem *elem, *next_elem;    /* For looping over existing elements */


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

  new_ht = (struct _ht *)sqlite3MallocZero( new_size*sizeof(struct _ht) );
  if( pH->htsize>0 ) sqlite3EndBenignMalloc();

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

  for(elem=pH->first, pH->first=0; elem; elem = next_elem){
    int h = strHash(elem->pKey, elem->nKey) & (new_size-1);
    next_elem = elem->next;
    insertElement(pH, &new_ht[h], elem);
  }
}

/* This function (for internal use only) locates an element in an
** hash table that matches the given key.  The hash for this key has
** already been computed and is passed as the 4th parameter.
*/
static HashElem *findElementGivenHash(
  const Hash *pH,     /* The pH to be searched */
  const void *pKey,   /* The key we are searching for */
  int nKey,
  int h               /* The hash for this key. */
){
  HashElem *elem;                /* Used to loop thru the element list */
  int count;                     /* Number of elements left to test */


  if( pH->ht ){
    struct _ht *pEntry = &pH->ht[h];
    elem = pEntry->chain;
    count = pEntry->count;

    while( count-- && elem ){
      if( strCompare(elem->pKey,elem->nKey,pKey,nKey)==0 ){ 
        return elem;
      }
      elem = elem->next;
    }
  }
  return 0;
}

** that matches pKey,nKey.  Return a pointer to the corresponding 
** HashElem structure for this element if it is found, or NULL
** otherwise.
*/
SQLITE_PRIVATE HashElem *sqlite3HashFindElem(const Hash *pH, const void *pKey, int nKey){
  int h;             /* A hash on key */
  HashElem *elem;    /* The element that matches key */


  if( pH==0 || pH->ht==0 ) return 0;


  h = strHash(pKey,nKey);
  elem = findElementGivenHash(pH,pKey,nKey, h % pH->htsize);
  return elem;
}

/* Attempt to locate an element of the hash table pH with a key
** that matches pKey,nKey.  Return the data for this element if it is
** found, or NULL if there is no match.

** element corresponding to "key" is removed from the hash table.
*/
SQLITE_PRIVATE void *sqlite3HashInsert(Hash *pH, const void *pKey, int nKey, void *data){
  int hraw;             /* Raw hash value of the key */
  int h;                /* the hash of the key modulo hash table size */
  HashElem *elem;       /* Used to loop thru the element list */
  HashElem *new_elem;   /* New element added to the pH */


  assert( pH!=0 );


  hraw = strHash(pKey, nKey);
  if( pH->htsize ){
    h = hraw % pH->htsize;
    elem = findElementGivenHash(pH,pKey,nKey,h);
    if( elem ){
      void *old_data = elem->data;
      if( data==0 ){
        removeElementGivenHash(pH,elem,h);

     /* 118 */ "Blob",
     /* 119 */ "Rewind",
     /* 120 */ "MoveGe",
     /* 121 */ "VBegin",
     /* 122 */ "VUpdate",
     /* 123 */ "IfZero",
     /* 124 */ "VCreate",
     /* 125 */ "Found",
     /* 126 */ "Real",
     /* 127 */ "IfPos",
     /* 128 */ "NullRow",
     /* 129 */ "Jump",
     /* 130 */ "Permutation",
     /* 131 */ "NotUsed_131",
     /* 132 */ "NotUsed_132",
     /* 133 */ "NotUsed_133",
     /* 134 */ "NotUsed_134",
     /* 135 */ "NotUsed_135",
     /* 136 */ "NotUsed_136",
     /* 137 */ "NotUsed_137",
     /* 138 */ "NotUsed_138",
     /* 139 */ "ToText",
     /* 140 */ "ToBlob",
     /* 141 */ "ToNumeric",
     /* 142 */ "ToInt",
     /* 143 */ "ToReal",
  };
  return azName[i];
}
#endif

/************** End of opcodes.c *********************************************/
/************** Begin file os_os2.c ******************************************/

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains code that is specific to OS/2.
**
** $Id: os_os2.c,v 1.57 2008/10/13 21:46:47 pweilbacher Exp $
*/


#if SQLITE_OS_OS2

/*
** A Note About Memory Allocation:

*/
static int os2Truncate( sqlite3_file *id, i64 nByte ){
  APIRET rc = NO_ERROR;
  os2File *pFile = (os2File*)id;
  OSTRACE3( "TRUNCATE %d %lld\n", pFile->h, nByte );
  SimulateIOError( return SQLITE_IOERR_TRUNCATE );
  rc = DosSetFileSize( pFile->h, nByte );
  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR_TRUNCATE;
}

#ifdef SQLITE_TEST
/*
** Count the number of fullsyncs and normal syncs.  This is used to test
** that syncs and fullsyncs are occuring at the right times.
*/

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

/*
** Acquire a reader lock.
*/
static int getReadLock( os2File *pFile ){

){
  APIRET rc = NO_ERROR;
  char *zFilenameCp = convertUtf8PathToCp( zFilename );
  SimulateIOError( return SQLITE_IOERR_DELETE );
  rc = DosDelete( (PSZ)zFilenameCp );
  free( zFilenameCp );
  OSTRACE2( "DELETE \"%s\"\n", zFilename );
  return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR_DELETE;
}

/*
** Check the existance and status of a file.
*/
static int os2Access(
  sqlite3_vfs *pVfs,        /* Not used on os2 */

**    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.
**
** $Id: os_unix.c,v 1.205 2008/10/14 17:58:38 drh Exp $
*/
#if SQLITE_OS_UNIX              /* This file is used on unix only */

/*
** If SQLITE_ENABLE_LOCKING_STYLE is defined and is non-zero, then several
** alternative locking implementations are provided:
**
**   * POSIX locking (the default),
**   * No locking,
**   * Dot-file locking,
**   * flock() locking,
**   * AFP locking (OSX only).
**
** SQLITE_ENABLE_LOCKING_STYLE only works on a Mac. It is turned on by
** default on a Mac and disabled on all other posix platforms.
*/
#if !defined(SQLITE_ENABLE_LOCKING_STYLE)
#  if defined(__DARWIN__)
#    define SQLITE_ENABLE_LOCKING_STYLE 1
#  else
#    define SQLITE_ENABLE_LOCKING_STYLE 0
#  endif
#endif

/*
** These #defines should enable >2GB file support on Posix if the
** underlying operating system supports it.  If the OS lacks
** large file support, these should be no-ops.
**
** Large file support can be disabled using the -DSQLITE_DISABLE_LFS switch

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/time.h>
#include <errno.h>

#if SQLITE_ENABLE_LOCKING_STYLE
#include <sys/ioctl.h>
#include <sys/param.h>
#include <sys/mount.h>
#endif /* SQLITE_ENABLE_LOCKING_STYLE */

/*
** If we are to be thread-safe, include the pthreads header and define

  /* In test mode, increase the size of this structure a bit so that 
  ** it is larger than the struct CrashFile defined in test6.c.
  */
  char aPadding[32];
#endif
  struct openCnt *pOpen;    /* Info about all open fd's on this inode */
  struct lockInfo *pLock;   /* Info about locks on this inode */
#if SQLITE_ENABLE_LOCKING_STYLE
  void *lockingContext;     /* Locking style specific state */
#endif
  int h;                    /* The file descriptor */
  unsigned char locktype;   /* The type of lock held on this fd */
  int dirfd;                /* File descriptor for the directory */
#if SQLITE_THREADSAFE
  pthread_t tid;            /* The thread that "owns" this unixFile */

** a normal expected return code of SQLITE_BUSY or SQLITE_OK
*/
#define IS_LOCK_ERROR(x)  ((x != SQLITE_OK) && (x != SQLITE_BUSY))

/*
** Helper functions to obtain and relinquish the global mutex.
*/
static void enterMutex(void){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
static void leaveMutex(void){
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}

#if SQLITE_THREADSAFE
/*
** This variable records whether or not threads can override each others
** locks.

      }
      sqlite3_free(pOpen->aPending);
      sqlite3_free(pOpen);
    }
  }
}

#if SQLITE_ENABLE_LOCKING_STYLE
/*
** Tests a byte-range locking query to see if byte range locks are 
** supported, if not we fall back to dotlockLockingStyle.
*/
static int testLockingStyle(int fd){
  struct flock lockInfo;

** returns LOCKING_STYLE_POSIX.
*/
static int detectLockingStyle(
  sqlite3_vfs *pVfs,
  const char *filePath, 
  int fd
){
#if SQLITE_ENABLE_LOCKING_STYLE
  struct Mapping {
    const char *zFilesystem;
    int eLockingStyle;
  } aMap[] = {
    { "hfs",    LOCKING_STYLE_POSIX },
    { "ufs",    LOCKING_STYLE_POSIX },
    { "afpfs",  LOCKING_STYLE_AFP },

  int isDataOnly = (flags&SQLITE_SYNC_DATAONLY);
  int isFullsync = (flags&0x0F)==SQLITE_SYNC_FULL;

  /* Check that one of SQLITE_SYNC_NORMAL or FULL was passed */
  assert((flags&0x0F)==SQLITE_SYNC_NORMAL
      || (flags&0x0F)==SQLITE_SYNC_FULL
  );

  /* Unix cannot, but some systems may return SQLITE_FULL from here. This
  ** line is to test that doing so does not cause any problems.
  */
  SimulateDiskfullError( return SQLITE_FULL );

  assert( pFile );
  OSTRACE2("SYNC    %-3d\n", pFile->h);
  rc = full_fsync(pFile->h, isFullsync, isDataOnly);
  SimulateIOError( rc=1 );
  if( rc ){
    return SQLITE_IOERR_FSYNC;

    closeUnixFile(id);
    leaveMutex();
  }
  return SQLITE_OK;
}


#if SQLITE_ENABLE_LOCKING_STYLE
#pragma mark AFP Support

/*
 ** The afpLockingContext structure contains all afp lock specific state
 */
typedef struct afpLockingContext afpLockingContext;
struct afpLockingContext {

    unixFileControl,            /* xFileControl */                       \
    unixSectorSize,             /* xSectorSize */                        \
    unixDeviceCharacteristics   /* xDeviceCapabilities */                \
  }
  static sqlite3_io_methods aIoMethod[] = {
    IOMETHODS(unixClose, unixLock, unixUnlock, unixCheckReservedLock) 
   ,IOMETHODS(nolockClose, nolockLock, nolockUnlock, nolockCheckReservedLock)
#if SQLITE_ENABLE_LOCKING_STYLE
   ,IOMETHODS(dotlockClose, dotlockLock, dotlockUnlock,dotlockCheckReservedLock)
   ,IOMETHODS(flockClose, flockLock, flockUnlock, flockCheckReservedLock)
   ,IOMETHODS(afpClose, afpLock, afpUnlock, afpCheckReservedLock)
#endif
  };
  /* The order of the IOMETHODS macros above is important.  It must be the
  ** same order as the LOCKING_STYLE numbers

    case LOCKING_STYLE_POSIX: {
      enterMutex();
      rc = findLockInfo(h, &pNew->pLock, &pNew->pOpen);
      leaveMutex();
      break;
    }

#if SQLITE_ENABLE_LOCKING_STYLE
    case LOCKING_STYLE_AFP: {
      /* AFP locking uses the file path so it needs to be included in
      ** the afpLockingContext.
      */
      afpLockingContext *pCtx;
      pNew->lockingContext = pCtx = sqlite3_malloc( sizeof(*pCtx) );
      if( pCtx==0 ){

    fd = open("/dev/urandom", O_RDONLY);
    if( fd<0 ){
      time_t t;
      time(&t);
      memcpy(zBuf, &t, sizeof(t));
      pid = getpid();
      memcpy(&zBuf[sizeof(t)], &pid, sizeof(pid));
      assert( sizeof(t)+sizeof(pid)<=nBuf );
      nBuf = sizeof(t) + sizeof(pid);
    }else{
      nBuf = read(fd, zBuf, nBuf);
      close(fd);
    }
  }
#endif
  return nBuf;
}


/*
** Sleep for a little while.  Return the amount of time slept.
** The argument is the number of microseconds we want to sleep.
** The return value is the number of microseconds of sleep actually

    unixRandomness,       /* xRandomness */                 \
    unixSleep,            /* xSleep */                      \
    unixCurrentTime,      /* xCurrentTime */                \
    unixGetLastError      /* xGetLastError */               \
  }

  static sqlite3_vfs unixVfs = UNIXVFS("unix", 0);
#if SQLITE_ENABLE_LOCKING_STYLE
  int i;
  static sqlite3_vfs aVfs[] = {
    UNIXVFS("unix-posix",   LOCKING_STYLE_POSIX), 
    UNIXVFS("unix-afp",     LOCKING_STYLE_AFP), 
    UNIXVFS("unix-flock",   LOCKING_STYLE_FLOCK), 
    UNIXVFS("unix-dotfile", LOCKING_STYLE_DOTFILE), 
    UNIXVFS("unix-none",    LOCKING_STYLE_NONE)

**    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.
**
** $Id: os_win.c,v 1.135 2008/10/12 02:27:39 shane Exp $
*/
#if SQLITE_OS_WIN               /* This file is used for windows only */


/*
** A Note About Memory Allocation:
**

#define MX_CLOSE_ATTEMPT 3
static int winClose(sqlite3_file *id){
  int rc, cnt = 0;
  winFile *pFile = (winFile*)id;
  OSTRACE2("CLOSE %d\n", pFile->h);
  do{
    rc = CloseHandle(pFile->h);
  }while( rc==0 && ++cnt < MX_CLOSE_ATTEMPT && (Sleep(100), 1) );
#if SQLITE_OS_WINCE
#define WINCE_DELETION_ATTEMPTS 3
  winceDestroyLock(pFile);
  if( pFile->zDeleteOnClose ){
    int cnt = 0;
    while(
           DeleteFileW(pFile->zDeleteOnClose)==0

  return SQLITE_OK;
}

/*
** Truncate an open file to a specified size
*/
static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
  DWORD rc;
  LONG upperBits = (nByte>>32) & 0x7fffffff;
  LONG lowerBits = nByte & 0xffffffff;
  winFile *pFile = (winFile*)id;
  OSTRACE3("TRUNCATE %d %lld\n", pFile->h, nByte);
  SimulateIOError(return SQLITE_IOERR_TRUNCATE);
  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
  if( INVALID_SET_FILE_POINTER != rc ){
    /* SetEndOfFile will fail if nByte is negative */
    if( SetEndOfFile(pFile->h) ){
      return SQLITE_OK;
    }
  }
  return SQLITE_IOERR_TRUNCATE;
}

#ifdef SQLITE_TEST
/*
** Count the number of fullsyncs and normal syncs.  This is used to test
** that syncs and fullsyncs are occuring at the right times.
*/

  int *pOutFlags            /* Status return flags */
){
  HANDLE h;
  DWORD dwDesiredAccess;
  DWORD dwShareMode;
  DWORD dwCreationDisposition;
  DWORD dwFlagsAndAttributes = 0;
#if SQLITE_OS_WINCE
  int isTemp = 0;
#endif
  winFile *pFile = (winFile*)id;
  void *zConverted;                 /* Filename in OS encoding */
  const char *zUtf8Name = zName;    /* Filename in UTF-8 encoding */
  char zTmpname[MAX_PATH+1];        /* Buffer used to create temp filename */

  /* If the second argument to this function is NULL, generate a 
  ** temporary file name to use 

    dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
  }else{
    dwShareMode = 0;
  }
  if( flags & SQLITE_OPEN_DELETEONCLOSE ){
#if SQLITE_OS_WINCE
    dwFlagsAndAttributes = FILE_ATTRIBUTE_HIDDEN;
    isTemp = 1;
#else
    dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY
                               | FILE_ATTRIBUTE_HIDDEN
                               | FILE_FLAG_DELETE_ON_CLOSE;
#endif

  }else{
    dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;

  }
  /* Reports from the internet are that performance is always
  ** better if FILE_FLAG_RANDOM_ACCESS is used.  Ticket #2699. */
#if SQLITE_OS_WINCE
  dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
#endif
  if( isNT() ){
    h = CreateFileW((WCHAR*)zConverted,
       dwDesiredAccess,
       dwShareMode,
       NULL,
       dwCreationDisposition,
       dwFlagsAndAttributes,

#define MX_DELETION_ATTEMPTS 5
static int winDelete(
  sqlite3_vfs *pVfs,          /* Not used on win32 */
  const char *zFilename,      /* Name of file to delete */
  int syncDir                 /* Not used on win32 */
){
  int cnt = 0;
  DWORD rc;
  DWORD error;
  void *zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    return SQLITE_NOMEM;
  }
  SimulateIOError(return SQLITE_IOERR_DELETE);
  if( isNT() ){
    do{
      DeleteFileW(zConverted);
    }while(   (   ((rc = GetFileAttributesW(zConverted)) != INVALID_FILE_ATTRIBUTES)
               || ((error = GetLastError()) == ERROR_ACCESS_DENIED))
           && (++cnt < MX_DELETION_ATTEMPTS)
           && (Sleep(100), 1) );
  }else{
    do{
      DeleteFileA(zConverted);
    }while(   (   ((rc = GetFileAttributesA(zConverted)) != INVALID_FILE_ATTRIBUTES)
               || ((error = GetLastError()) == ERROR_ACCESS_DENIED))
           && (++cnt < MX_DELETION_ATTEMPTS)
           && (Sleep(100), 1) );
  }
  free(zConverted);
  OSTRACE2("DELETE \"%s\"\n", zFilename);
  return (   (rc == INVALID_FILE_ATTRIBUTES) 
          && (error == ERROR_FILE_NOT_FOUND)) ? SQLITE_OK : SQLITE_IOERR_DELETE;
}

/*
** Check the existance and status of a file.
*/
static int winAccess(

**    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 implements that page cache.
**
** @(#) $Id: pcache.c,v 1.33 2008/09/29 11:49:48 danielk1977 Exp $
*/

/*
** A complete page cache is an instance of this structure.
**
** A cache may only be deleted by its owner and while holding the
** SQLITE_MUTEX_STATUS_LRU mutex.

  ** the cache owner or by any thread holding the the mutex.  Non-owner
  ** threads must hold the mutex when reading these elements to prevent
  ** the entire PCache object from being deleted during the read.
  */
  int szPage;                         /* Size of every page in this cache */
  int szExtra;                        /* Size of extra space for each page */
  int bPurgeable;                     /* True if pages are on backing store */

  int (*xStress)(void*,PgHdr*);       /* Call to try make a page clean */
  void *pStress;                      /* Argument to xStress */
  /**********************************************************************
  ** The final group of elements can only be accessed while holding the
  ** mutex.  Both the cache owner and any other thread must hold the mutex
  ** to read or write any of these elements.
  */

** This function removes page pcache.pLruTail from the global LRU list,
** and from the hash-table and PCache.pClean list of the owner pcache.
** There should be no other references to the page.
**
** A pointer to the recycled page is returned, or NULL if no page is
** eligible for recycling.
*/
static PgHdr *pcacheRecyclePage(void){
  PgHdr *p = 0;
  assert( sqlite3_mutex_held(pcache_g.mutex) );

  if( (p=pcache_g.pLruTail) ){
    assert( (p->flags&PGHDR_DIRTY)==0 );
    pcacheRemoveFromLruList(p);
    pcacheRemoveFromHash(p);

** Create a new PCache object.  Storage space to hold the object
** has already been allocated and is passed in as the p pointer.
*/
SQLITE_PRIVATE void sqlite3PcacheOpen(
  int szPage,                  /* Size of every page */
  int szExtra,                 /* Extra space associated with each page */
  int bPurgeable,              /* True if pages are on backing store */

  int (*xStress)(void*,PgHdr*),/* Call to try to make pages clean */
  void *pStress,               /* Argument to xStress */
  PCache *p                    /* Preallocated space for the PCache */
){
  assert( pcache_g.isInit );
  memset(p, 0, sizeof(PCache));
  p->szPage = szPage;
  p->szExtra = szExtra;
  p->bPurgeable = bPurgeable;

  p->xStress = xStress;
  p->pStress = pStress;
  p->nMax = 100;
  p->nMin = 10;

  pcacheEnterMutex();
  if( bPurgeable ){

** move the page to the LRU list if it is clean.
*/
SQLITE_PRIVATE void sqlite3PcacheRelease(PgHdr *p){
  assert( p->nRef>0 );
  p->nRef--;
  if( p->nRef==0 ){
    PCache *pCache = p->pCache;



    pCache->nRef--;
    if( (p->flags&PGHDR_DIRTY)==0 ){
      pCache->nPinned--;
      pcacheEnterMutex();
      if( pcache_g.nCurrentPage>pcache_g.nMaxPage ){
        pcacheRemoveFromList(&pCache->pClean, p);
        pcacheRemoveFromHash(p);

  pcacheExitMutex();
}

/*
** If there are currently more than pcache.nMaxPage pages allocated, try
** to recycle pages to reduce the number allocated to pcache.nMaxPage.
*/
static void pcacheEnforceMaxPage(void){
  PgHdr *p;
  assert( sqlite3_mutex_held(pcache_g.mutex) );
  while( pcache_g.nCurrentPage>pcache_g.nMaxPage && (p = pcacheRecyclePage()) ){
    pcachePageFree(p);
  }
}

/* 
** Return the total number of outstanding page references.
*/
SQLITE_PRIVATE int sqlite3PcacheRefCount(PCache *pCache){
  return pCache->nRef;
}

SQLITE_PRIVATE int sqlite3PcachePageRefcount(PgHdr *p){
  return p->nRef;
}

/* 
** Return the total number of pages in the cache.
*/
SQLITE_PRIVATE int sqlite3PcachePagecount(PCache *pCache){
  assert( pCache->nPage>=0 );
  return pCache->nPage;

** 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 1.497 2008/10/07 11:51:20 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO

/*
** Macros for troubleshooting.  Normally turned off
*/
#if 0

  }
  sqlite3PagerStmtCommit(pPager);
  if( pPager->stmtOpen && !pPager->exclusiveMode ){
    sqlite3OsClose(pPager->stfd);
    pPager->stmtOpen = 0;
  }
  if( pPager->journalOpen ){
    if( pPager->journalMode==PAGER_JOURNALMODE_TRUNCATE
         && (rc = sqlite3OsTruncate(pPager->jfd, 0))==SQLITE_OK ){
      pPager->journalOff = 0;
      pPager->journalStarted = 0;
    }else if( pPager->exclusiveMode 
     || pPager->journalMode==PAGER_JOURNALMODE_PERSIST
    ){
      rc = zeroJournalHdr(pPager, hasMaster);
      pager_error(pPager, rc);
      pPager->journalOff = 0;
      pPager->journalStarted = 0;
    }else{
      assert( pPager->journalMode==PAGER_JOURNALMODE_DELETE || rc );
      sqlite3OsClose(pPager->jfd);
      pPager->journalOpen = 0;
      if( rc==SQLITE_OK && !pPager->tempFile ){
        rc = sqlite3OsDelete(pPager->pVfs, pPager->zJournal, 0);
      }
    }
    sqlite3BitvecDestroy(pPager->pInJournal);

          pPager->journalOff = szJ;
          break;
        }else{
          /* If we are unable to rollback, then the database is probably
          ** going to end up being corrupt.  It is corrupt to us, anyhow.
          ** Perhaps the next process to come along can fix it....
          */
          rc = SQLITE_CORRUPT_BKPT;
          goto end_playback;
        }
      }
    }
  }
  /*NOTREACHED*/
  assert( 0 );

end_playback:
  if( rc==SQLITE_OK ){
    zMaster = pPager->pTmpSpace;
    rc = readMasterJournal(pPager->jfd, zMaster, pPager->pVfs->mxPathname+1);
  }
  if( rc==SQLITE_OK ){
    rc = pager_end_transaction(pPager, zMaster[0]!='\0');
  }
  if( rc==SQLITE_OK && zMaster[0] && res ){
    /* If there was a master journal and this routine will return success,
    ** see if it is possible to delete the master journal.
    */
    rc = pager_delmaster(pPager, zMaster);
  }

  /* The Pager.sectorSize variable may have been updated while rolling

** It is never written to disk.  This can be used to implement an
** in-memory database.
*/
SQLITE_PRIVATE int sqlite3PagerOpen(
  sqlite3_vfs *pVfs,       /* The virtual file system to use */
  Pager **ppPager,         /* Return the Pager structure here */
  const char *zFilename,   /* Name of the database file to open */

  int nExtra,              /* Extra bytes append to each in-memory page */
  int flags,               /* flags controlling this file */
  int vfsFlags             /* flags passed through to sqlite3_vfs.xOpen() */
){
  u8 *pPtr;
  Pager *pPager = 0;
  int rc = SQLITE_OK;

  */
  if( !pPager || !pPager->pTmpSpace ){
    sqlite3OsClose(pPager->fd);
    sqlite3_free(pPager);
    return ((rc==SQLITE_OK)?SQLITE_NOMEM:rc);
  }
  nExtra = FORCE_ALIGNMENT(nExtra);
  sqlite3PcacheOpen(szPageDflt, nExtra, !memDb,
                    !memDb?pagerStress:0, (void *)pPager, pPager->pPCache);

  PAGERTRACE3("OPEN %d %s\n", FILEHANDLEID(pPager->fd), pPager->zFilename);
  IOTRACE(("OPEN %p %s\n", pPager, pPager->zFilename))

  /* Fill in Pager.zDirectory[] */
  memcpy(pPager->zDirectory, pPager->zFilename, nPathname+1);

/*
** Return the number of references to the pager.
*/
SQLITE_PRIVATE int sqlite3PagerRefcount(Pager *pPager){
  return sqlite3PcacheRefCount(pPager->pPCache);
}

/*
** Return the number of references to the specified page.
*/
SQLITE_PRIVATE int sqlite3PagerPageRefcount(DbPage *pPage){
  return sqlite3PcachePageRefcount(pPage);
}

#ifdef SQLITE_TEST
/*
** This routine is used for testing and analysis only.
*/
SQLITE_PRIVATE int *sqlite3PagerStats(Pager *pPager){
  static int a[11];

}
#endif

/*
** Return a pointer to the data for the specified page.
*/
SQLITE_PRIVATE void *sqlite3PagerGetData(DbPage *pPg){
  assert( pPg->nRef>0 || pPg->pPager->memDb );
  return pPg->pData;
}

/*
** Return a pointer to the Pager.nExtra bytes of "extra" space 
** allocated along with the specified page.
*/

  if( eMode>=0 && !pPager->tempFile ){
    pPager->exclusiveMode = eMode;
  }
  return (int)pPager->exclusiveMode;
}

/*
** Get/set the journal-mode for this pager. Parameter eMode must be one of:
**
**    PAGER_JOURNALMODE_QUERY
**    PAGER_JOURNALMODE_DELETE
**    PAGER_JOURNALMODE_TRUNCATE
**    PAGER_JOURNALMODE_PERSIST
**    PAGER_JOURNALMODE_OFF
**
** If the parameter is not _QUERY, then the journal-mode is set to the
** value specified.
**

** The returned indicate the current (possibly updated)
** journal-mode.
*/
SQLITE_PRIVATE int sqlite3PagerJournalMode(Pager *pPager, int eMode){
  assert( eMode==PAGER_JOURNALMODE_QUERY
            || eMode==PAGER_JOURNALMODE_DELETE
            || eMode==PAGER_JOURNALMODE_TRUNCATE
            || eMode==PAGER_JOURNALMODE_PERSIST
            || eMode==PAGER_JOURNALMODE_OFF );
  assert( PAGER_JOURNALMODE_QUERY<0 );

  if( eMode>=0 ){
    pPager->journalMode = eMode;
  }else{
    assert( eMode==PAGER_JOURNALMODE_QUERY );
  }
  return (int)pPager->journalMode;
}

/*
** Get/set the size-limit used for persistent journal files.
*/

**
**    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: btmutex.c,v 1.11 2008/10/07 15:25:48 drh Exp $
**
** This file contains code used to implement mutexes on Btree objects.
** This code really belongs in btree.c.  But btree.c is getting too
** big and we want to break it down some.  This packaged seemed like
** a good breakout.
*/
/************** Include btreeInt.h in the middle of btmutex.c ****************/
/************** Begin file btreeInt.h ****************************************/
/*
** 2004 April 6
**
** 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.
**
*************************************************************************
** $Id: btreeInt.h,v 1.34 2008/09/30 17:18:17 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.

** The pageDestructor() routine handles that chore.
**
** Access to all fields of this structure is controlled by the mutex
** stored in MemPage.pBt->mutex.
*/
struct MemPage {
  u8 isInit;           /* True if previously initialized. MUST BE FIRST! */

  u8 nOverflow;        /* Number of overflow cell bodies in aCell[] */
  u8 intKey;           /* True if intkey flag is set */
  u8 leaf;             /* True if leaf flag is set */
  u8 hasData;          /* True if this page stores data */
  u8 hdrOffset;        /* 100 for page 1.  0 otherwise */
  u8 childPtrSize;     /* 0 if leaf==1.  4 if leaf==0 */
  u16 maxLocal;        /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
  u16 minLocal;        /* Copy of BtShared.minLocal or BtShared.minLeaf */
  u16 cellOffset;      /* Index in aData of first cell pointer */

  u16 nFree;           /* Number of free bytes on the page */
  u16 nCell;           /* Number of cells on this page, local and ovfl */
  u16 maskPage;        /* Mask for page offset */
  struct _OvflCell {   /* Cells that will not fit on aData[] */
    u8 *pCell;          /* Pointers to the body of the overflow cell */
    u16 idx;            /* Insert this cell before idx-th non-overflow cell */
  } aOvfl[5];
  BtShared *pBt;       /* Pointer to BtShared that this page is part of */
  u8 *aData;           /* Pointer to disk image of the page data */
  DbPage *pDbPage;     /* Pager page handle */
  Pgno pgno;           /* Page number for this page */

};













/*
** The in-memory image of a disk page has the auxiliary information appended
** to the end.  EXTRA_SIZE is the number of bytes of space needed to hold
** that extra information.
*/
#define EXTRA_SIZE sizeof(MemPage)

  u32 nPayload;  /* Total amount of payload */
  u16 nHeader;   /* Size of the cell content header in bytes */
  u16 nLocal;    /* Amount of payload held locally */
  u16 iOverflow; /* Offset to overflow page number.  Zero if no overflow */
  u16 nSize;     /* Size of the cell content on the main b-tree page */
};

/*
** Maximum depth of an SQLite B-Tree structure. Any B-Tree deeper than
** this will be declared corrupt. This value is calculated based on a
** maximum database size of 2^31 pages a minimum fanout of 2 for a
** root-node and 3 for all other internal nodes.
**
** If a tree that appears to be taller than this is encountered, it is
** assumed that the database is corrupt.
*/
#define BTCURSOR_MAX_DEPTH 20

/*
** A cursor is a pointer to a particular entry within a particular
** b-tree within a database file.
**
** The entry is identified by its MemPage and the index in
** MemPage.aCell[] of the entry.
**
** When a single database file can shared by two more database connections,
** but cursors cannot be shared.  Each cursor is associated with a
** particular database connection identified BtCursor.pBtree.db.
**
** Fields in this structure are accessed under the BtShared.mutex
** found at self->pBt->mutex. 
*/
struct BtCursor {
  Btree *pBtree;            /* The Btree to which this cursor belongs */
  BtShared *pBt;            /* The BtShared this cursor points to */
  BtCursor *pNext, *pPrev;  /* Forms a linked list of all cursors */
  struct KeyInfo *pKeyInfo; /* Argument passed to comparison function */
  Pgno pgnoRoot;            /* The root page of this tree */


  CellInfo info;            /* A parse of the cell we are pointing at */
  u8 wrFlag;                /* True if writable */
  u8 atLast;                /* Cursor pointing to the last entry */
  u8 validNKey;             /* True if info.nKey is valid */
  u8 eState;                /* One of the CURSOR_XXX constants (see below) */
  void *pKey;      /* Saved key that was cursor's last known position */
  i64 nKey;        /* Size of pKey, or last integer key */
  int skip;        /* (skip<0) -> Prev() is a no-op. (skip>0) -> Next() is */
#ifndef SQLITE_OMIT_INCRBLOB
  u8 isIncrblobHandle;      /* True if this cursor is an incr. io handle */
  Pgno *aOverflow;          /* Cache of overflow page locations */
#endif
#ifndef NDEBUG
  u8 pagesShuffled;         /* True if Btree pages are rearranged by balance()*/
#endif
  i16 iPage;                            /* Index of current page in apPage */
  MemPage *apPage[BTCURSOR_MAX_DEPTH];  /* Pages from root to current page */
  u16 aiIdx[BTCURSOR_MAX_DEPTH];        /* Current index in apPage[i] */
};

/*
** Potential values for BtCursor.eState.
**
** CURSOR_VALID:
**   Cursor points to a valid entry. getPayload() etc. may be called.

#define get4byte sqlite3Get4byte
#define put4byte sqlite3Put4byte

/*
** Internal routines that should be accessed by the btree layer only.
*/
SQLITE_PRIVATE int sqlite3BtreeGetPage(BtShared*, Pgno, MemPage**, int);
SQLITE_PRIVATE int sqlite3BtreeInitPage(MemPage *pPage);
SQLITE_PRIVATE void sqlite3BtreeParseCellPtr(MemPage*, u8*, CellInfo*);
SQLITE_PRIVATE void sqlite3BtreeParseCell(MemPage*, int, CellInfo*);
SQLITE_PRIVATE int sqlite3BtreeRestoreCursorPosition(BtCursor *pCur);
SQLITE_PRIVATE void sqlite3BtreeGetTempCursor(BtCursor *pCur, BtCursor *pTempCur);
SQLITE_PRIVATE void sqlite3BtreeReleaseTempCursor(BtCursor *pCur);

SQLITE_PRIVATE void sqlite3BtreeMoveToParent(BtCursor *pCur);

/************** End of btreeInt.h ********************************************/
/************** Continuing where we left off in btmutex.c ********************/
#if SQLITE_THREADSAFE && !defined(SQLITE_OMIT_SHARED_CACHE)

  /* We should already hold a lock on the database connection */
  assert( sqlite3_mutex_held(p->db->mutex) );

  if( !p->sharable ) return;
  p->wantToLock++;
  if( p->locked ) return;


  /* In most cases, we should be able to acquire the lock we
  ** want without having to go throught the ascending lock
  ** procedure that follows.  Just be sure not to block.
  */
  if( sqlite3_mutex_try(p->pBt->mutex)==SQLITE_OK ){
    p->locked = 1;
    return;

  p->locked = 1;
  for(pLater=p->pNext; pLater; pLater=pLater->pNext){
    if( pLater->wantToLock ){
      sqlite3_mutex_enter(pLater->pBt->mutex);
      pLater->locked = 1;
    }
  }

}

/*
** Exit the recursive mutex on a Btree.
*/
SQLITE_PRIVATE void sqlite3BtreeLeave(Btree *p){
  if( p->sharable ){

** 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 1.525 2008/10/08 17:58:49 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
** Including a description of file format and an overview of operation.
*/

/*

#if 0
int sqlite3BtreeTrace=0;  /* True to enable tracing */
# define TRACE(X)  if(sqlite3BtreeTrace){printf X;fflush(stdout);}
#else
# define TRACE(X)
#endif

/*
** Sometimes we need a small amount of code such as a variable initialization
** to setup for a later assert() statement.  We do not want this code to
** appear when assert() is disabled.  The following macro is therefore
** used to contain that setup code.  The "VVA" acronym stands for
** "Verification, Validation, and Accreditation".  In other words, the
** code within VVA_ONLY() will only run during verification processes.
*/
#ifndef NDEBUG
# define VVA_ONLY(X)  X
#else
# define VVA_ONLY(X)
#endif



#ifndef SQLITE_OMIT_SHARED_CACHE
/*
** A list of BtShared objects that are eligible for participation
** in shared cache.  This variable has file scope during normal builds,
** but the test harness needs to access it so we make it global for 

  /* If this is an intKey table, then the above call to BtreeKeySize()
  ** stores the integer key in pCur->nKey. In this case this value is
  ** all that is required. Otherwise, if pCur is not open on an intKey
  ** table, then malloc space for and store the pCur->nKey bytes of key 
  ** data.
  */
  if( rc==SQLITE_OK && 0==pCur->apPage[0]->intKey){
    void *pKey = sqlite3Malloc(pCur->nKey);
    if( pKey ){
      rc = sqlite3BtreeKey(pCur, 0, pCur->nKey, pKey);
      if( rc==SQLITE_OK ){
        pCur->pKey = pKey;
      }else{
        sqlite3_free(pKey);
      }
    }else{
      rc = SQLITE_NOMEM;
    }
  }
  assert( !pCur->apPage[0]->intKey || !pCur->pKey );

  if( rc==SQLITE_OK ){
    int i;
    for(i=0; i<=pCur->iPage; i++){
      releasePage(pCur->apPage[i]);
      pCur->apPage[i] = 0;
    }
    pCur->iPage = -1;
    pCur->eState = CURSOR_REQUIRESEEK;
  }

  invalidateOverflowCache(pCur);
  return rc;
}

  }
  return SQLITE_OK;
}

/*
** Clear the current cursor position.
*/
SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *pCur){
  assert( cursorHoldsMutex(pCur) );
  sqlite3_free(pCur->pKey);
  pCur->pKey = 0;
  pCur->eState = CURSOR_INVALID;
}

/*

  }
  return SQLITE_OK;
}

/*
** Initialize the auxiliary information for a disk block.
**




** Return SQLITE_OK on success.  If we see that the page does
** not contain a well-formed database page, then return 
** SQLITE_CORRUPT.  Note that a return of SQLITE_OK does not
** guarantee that the page is well-formed.  It only shows that
** we failed to detect any corruption.
*/
SQLITE_PRIVATE int sqlite3BtreeInitPage(MemPage *pPage){

  assert( pPage->pBt!=0 );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
  assert( pPage == sqlite3PagerGetExtra(pPage->pDbPage) );
  assert( pPage->aData == sqlite3PagerGetData(pPage->pDbPage) );

  if( !pPage->isInit ){
    int pc;            /* Address of a freeblock within pPage->aData[] */
    int hdr;           /* Offset to beginning of page header */
    u8 *data;          /* Equal to pPage->aData */
    BtShared *pBt;        /* The main btree structure */
    int usableSize;    /* Amount of usable space on each page */
    int cellOffset;    /* Offset from start of page to first cell pointer */
    int nFree;         /* Number of unused bytes on the page */
    int top;           /* First byte of the cell content area */

    pBt = pPage->pBt;




















    hdr = pPage->hdrOffset;
    data = pPage->aData;
    if( decodeFlags(pPage, data[hdr]) ) return SQLITE_CORRUPT_BKPT;
    assert( pBt->pageSize>=512 && pBt->pageSize<=32768 );
    pPage->maskPage = pBt->pageSize - 1;
    pPage->nOverflow = 0;

    usableSize = pBt->usableSize;
    pPage->cellOffset = cellOffset = hdr + 12 - 4*pPage->leaf;
    top = get2byte(&data[hdr+5]);
    pPage->nCell = get2byte(&data[hdr+3]);
    if( pPage->nCell>MX_CELL(pBt) ){
      /* To many cells for a single page.  The page must be corrupt */
      return SQLITE_CORRUPT_BKPT;
    }




  
    /* Compute the total free space on the page */
    pc = get2byte(&data[hdr+1]);
    nFree = data[hdr+7] + top - (cellOffset + 2*pPage->nCell);
    while( pc>0 ){
      int next, size;
      if( pc>usableSize-4 ){

      pc = next;
    }
    pPage->nFree = nFree;
    if( nFree>=usableSize ){
      /* Free space cannot exceed total page size */
      return SQLITE_CORRUPT_BKPT; 
    }


#if 0
  /* Check that all the offsets in the cell offset array are within range. 
  ** 
  ** Omitting this consistency check and using the pPage->maskPage mask
  ** to prevent overrunning the page buffer in findCell() results in a
  ** 2.5% performance gain.

    for(pOff=&data[cellOffset]; pOff!=pEnd && !((*pOff)&mask); pOff+=2);
    if( pOff!=pEnd ){
      return SQLITE_CORRUPT_BKPT;
    }
  }
#endif

    pPage->isInit = 1;
  }
  return SQLITE_OK;
}

/*
** Set up a raw page so that it looks like a database page holding
** no entries.
*/

  pPage->nFree = pBt->usableSize - first;
  decodeFlags(pPage, flags);
  pPage->hdrOffset = hdr;
  pPage->cellOffset = first;
  pPage->nOverflow = 0;
  assert( pBt->pageSize>=512 && pBt->pageSize<=32768 );
  pPage->maskPage = pBt->pageSize - 1;

  pPage->nCell = 0;
  pPage->isInit = 1;
}


/*
** Convert a DbPage obtained from the pager into a MemPage used by
** the btree layer.
*/

** Get a page from the pager and initialize it.  This routine
** is just a convenience wrapper around separate calls to
** sqlite3BtreeGetPage() and sqlite3BtreeInitPage().
*/
static int getAndInitPage(
  BtShared *pBt,          /* The database file */
  Pgno pgno,           /* Number of the page to get */
  MemPage **ppPage     /* Write the page pointer here */

){
  int rc;
  DbPage *pDbPage;
  MemPage *pPage;

  assert( sqlite3_mutex_held(pBt->mutex) );

  if( pgno==0 ){
    return SQLITE_CORRUPT_BKPT; 
  }

  /* It is often the case that the page we want is already in cache.
  ** If so, get it directly.  This saves us from having to call
  ** pagerPagecount() to make sure pgno is within limits, which results

    if( pgno>pagerPagecount(pBt->pPager) ){
      return SQLITE_CORRUPT_BKPT; 
    }
    rc = sqlite3BtreeGetPage(pBt, pgno, ppPage, 0);
    if( rc ) return rc;
    pPage = *ppPage;
  }
  if( !pPage->isInit ){
    rc = sqlite3BtreeInitPage(pPage);






  }
  if( rc!=SQLITE_OK ){
    releasePage(pPage);
    *ppPage = 0;
  }
  return rc;
}

    assert( sqlite3PagerGetExtra(pPage->pDbPage) == (void*)pPage );
    assert( sqlite3PagerGetData(pPage->pDbPage)==pPage->aData );
    assert( sqlite3_mutex_held(pPage->pBt->mutex) );
    sqlite3PagerUnref(pPage->pDbPage);
  }
}

























/*
** During a rollback, when the pager reloads information into the cache
** so that the cache is restored to its original state at the start of
** the transaction, for each page restored this routine is called.
**
** This routine needs to reset the extra data section at the end of the
** page to agree with the restored data.
*/
static void pageReinit(DbPage *pData){
  MemPage *pPage;
  pPage = (MemPage *)sqlite3PagerGetExtra(pData);
  if( pPage->isInit ){
    assert( sqlite3_mutex_held(pPage->pBt->mutex) );
    pPage->isInit = 0;
    if( sqlite3PagerPageRefcount(pData)>0 ){
      sqlite3BtreeInitPage(pPage);


    }
  }
}

/*
** Invoke the busy handler for a btree.
*/
static int sqlite3BtreeInvokeBusyHandler(void *pArg, int n){

    pBt = sqlite3MallocZero( sizeof(*pBt) );
    if( pBt==0 ){
      rc = SQLITE_NOMEM;
      goto btree_open_out;
    }
    pBt->busyHdr.xFunc = sqlite3BtreeInvokeBusyHandler;
    pBt->busyHdr.pArg = pBt;
    rc = sqlite3PagerOpen(pVfs, &pBt->pPager, zFilename,
                          EXTRA_SIZE, flags, vfsFlags);
    if( rc==SQLITE_OK ){
      rc = sqlite3PagerReadFileheader(pBt->pPager,sizeof(zDbHeader),zDbHeader);
    }
    if( rc!=SQLITE_OK ){
      goto btree_open_out;
    }

  int nCell;                         /* Number of cells in page pPage */
  int rc;                            /* Return code */
  BtShared *pBt = pPage->pBt;
  int isInitOrig = pPage->isInit;
  Pgno pgno = pPage->pgno;

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  rc = sqlite3BtreeInitPage(pPage);
  if( rc!=SQLITE_OK ){
    goto set_child_ptrmaps_out;
  }
  nCell = pPage->nCell;

  for(i=0; i<nCell; i++){
    u8 *pCell = findCell(pPage, i);

    rc = ptrmapPutOvflPtr(pPage, pCell);
    if( rc!=SQLITE_OK ){
      goto set_child_ptrmaps_out;
    }

    if( !pPage->leaf ){
      Pgno childPgno = get4byte(pCell);
      rc = ptrmapPut(pBt, childPgno, PTRMAP_BTREE, pgno);
      if( rc!=SQLITE_OK ) goto set_child_ptrmaps_out;
    }
  }

  if( !pPage->leaf ){
    Pgno childPgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
    rc = ptrmapPut(pBt, childPgno, PTRMAP_BTREE, pgno);
  }

    }
    put4byte(pPage->aData, iTo);
  }else{
    int isInitOrig = pPage->isInit;
    int i;
    int nCell;

    sqlite3BtreeInitPage(pPage);
    nCell = pPage->nCell;

    for(i=0; i<nCell; i++){
      u8 *pCell = findCell(pPage, i);
      if( eType==PTRMAP_OVERFLOW1 ){
        CellInfo info;
        sqlite3BtreeParseCellPtr(pPage, pCell, &info);

** the database file should be truncated to during the commit process. 
** i.e. the database has been reorganized so that only the first *pnTrunc
** pages are in use.
*/
static int autoVacuumCommit(BtShared *pBt, Pgno *pnTrunc){
  int rc = SQLITE_OK;
  Pager *pPager = pBt->pPager;

  VVA_ONLY( int nRef = sqlite3PagerRefcount(pPager) );


  assert( sqlite3_mutex_held(pBt->mutex) );
  invalidateAllOverflowCache(pBt);
  assert(pBt->autoVacuum);
  if( !pBt->incrVacuum ){
    Pgno nFin = 0;

** save the state of the cursor.  The cursor must be
** invalidated.
*/
SQLITE_PRIVATE void sqlite3BtreeTripAllCursors(Btree *pBtree, int errCode){
  BtCursor *p;
  sqlite3BtreeEnter(pBtree);
  for(p=pBtree->pBt->pCursor; p; p=p->pNext){
    sqlite3BtreeClearCursor(p);
    p->eState = CURSOR_FAULT;
    p->skip = errCode;
  }
  sqlite3BtreeLeave(pBtree);
}

/*

** 3:  The database must be writable (not on read-only media)
**
** 4:  There must be an active transaction.
**
** No checking is done to make sure that page iTable really is the
** root page of a b-tree.  If it is not, then the cursor acquired
** will not work correctly.
**
** It is assumed that the sqlite3BtreeCursorSize() bytes of memory 
** pointed to by pCur have been zeroed by the caller.
*/
static int btreeCursor(
  Btree *p,                              /* The btree */
  int iTable,                            /* Root page of table to open */
  int wrFlag,                            /* 1 to write. 0 read-only */
  struct KeyInfo *pKeyInfo,              /* First arg to comparison function */
  BtCursor *pCur                         /* Space for new cursor */

    }
  }
  pCur->pgnoRoot = (Pgno)iTable;
  if( iTable==1 && pagerPagecount(pBt->pPager)==0 ){
    rc = SQLITE_EMPTY;
    goto create_cursor_exception;
  }
  rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->apPage[0]);
  if( rc!=SQLITE_OK ){
    goto create_cursor_exception;
  }

  /* Now that no other errors can occur, finish filling in the BtCursor
  ** variables, link the cursor into the BtShared list and set *ppCur (the
  ** output argument to this function).

  }
  pBt->pCursor = pCur;
  pCur->eState = CURSOR_INVALID;

  return SQLITE_OK;

create_cursor_exception:
  releasePage(pCur->apPage[0]);
  unlockBtreeIfUnused(pBt);
  return rc;
}
SQLITE_PRIVATE int sqlite3BtreeCursor(
  Btree *p,                                   /* The btree */
  int iTable,                                 /* Root page of table to open */
  int wrFlag,                                 /* 1 to write. 0 read-only */

/*
** Close a cursor.  The read lock on the database file is released
** when the last cursor is closed.
*/
SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor *pCur){
  Btree *pBtree = pCur->pBtree;
  if( pBtree ){
    int i;
    BtShared *pBt = pCur->pBt;
    sqlite3BtreeEnter(pBtree);
    pBt->db = pBtree->db;
    sqlite3BtreeClearCursor(pCur);
    if( pCur->pPrev ){
      pCur->pPrev->pNext = pCur->pNext;
    }else{
      pBt->pCursor = pCur->pNext;
    }
    if( pCur->pNext ){
      pCur->pNext->pPrev = pCur->pPrev;
    }
    for(i=0; i<=pCur->iPage; i++){
      releasePage(pCur->apPage[i]);
    }
    unlockBtreeIfUnused(pBt);
    invalidateOverflowCache(pCur);
    /* sqlite3_free(pCur); */
    sqlite3BtreeLeave(pBtree);
  }
  return SQLITE_OK;
}

/*
** Make a temporary cursor by filling in the fields of pTempCur.
** The temporary cursor is not on the cursor list for the Btree.
*/
SQLITE_PRIVATE void sqlite3BtreeGetTempCursor(BtCursor *pCur, BtCursor *pTempCur){
  int i;
  assert( cursorHoldsMutex(pCur) );
  memcpy(pTempCur, pCur, sizeof(BtCursor));
  pTempCur->pNext = 0;
  pTempCur->pPrev = 0;
  for(i=0; i<=pTempCur->iPage; i++){
    sqlite3PagerRef(pTempCur->apPage[i]->pDbPage);
  }
}

/*
** Delete a temporary cursor such as was made by the CreateTemporaryCursor()
** function above.
*/
SQLITE_PRIVATE void sqlite3BtreeReleaseTempCursor(BtCursor *pCur){
  int i;
  assert( cursorHoldsMutex(pCur) );
  for(i=0; i<=pCur->iPage; i++){
    sqlite3PagerUnref(pCur->apPage[i]->pDbPage);
  }
}

/*
** Make sure the BtCursor* given in the argument has a valid
** BtCursor.info structure.  If it is not already valid, call
** sqlite3BtreeParseCell() to fill it in.

** (when less compiler optimizations like -Os or -O0 are used and the
** compiler is not doing agressive inlining.)  So we use a real function
** for MSVC and a macro for everything else.  Ticket #2457.
*/
#ifndef NDEBUG
  static void assertCellInfo(BtCursor *pCur){
    CellInfo info;
    int iPage = pCur->iPage;
    memset(&info, 0, sizeof(info));
    sqlite3BtreeParseCell(pCur->apPage[iPage], pCur->aiIdx[iPage], &info);
    assert( memcmp(&info, &pCur->info, sizeof(info))==0 );
  }
#else
  #define assertCellInfo(x)
#endif
#ifdef _MSC_VER
  /* Use a real function in MSVC to work around bugs in that compiler. */
  static void getCellInfo(BtCursor *pCur){
    if( pCur->info.nSize==0 ){
      int iPage = pCur->iPage;
      sqlite3BtreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info);
      pCur->validNKey = 1;
    }else{
      assertCellInfo(pCur);
    }
  }
#else /* if not _MSC_VER */
  /* Use a macro in all other compilers so that the function is inlined */
#define getCellInfo(pCur)                                                      \
  if( pCur->info.nSize==0 ){                                                   \
    int iPage = pCur->iPage;                                                   \
    sqlite3BtreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info); \
    pCur->validNKey = 1;                                                       \
  }else{                                                                       \
    assertCellInfo(pCur);                                                      \
  }
#endif /* _MSC_VER */

/*
** Set *pSize to the size of the buffer needed to hold the value of
** the key for the current entry.  If the cursor is not pointing
** to a valid entry, *pSize is set to 0. 

  int skipKey,         /* offset begins at data if this is true */
  int eOp              /* zero to read. non-zero to write. */
){
  unsigned char *aPayload;
  int rc = SQLITE_OK;
  u32 nKey;
  int iIdx = 0;
  MemPage *pPage = pCur->apPage[pCur->iPage]; /* Btree page of current entry */
  BtShared *pBt;                              /* Btree this cursor belongs to */

  assert( pPage );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
  assert( offset>=0 );
  assert( cursorHoldsMutex(pCur) );

  getCellInfo(pCur);
  aPayload = pCur->info.pCell + pCur->info.nHeader;
  nKey = (pPage->intKey ? 0 : pCur->info.nKey);

SQLITE_PRIVATE int sqlite3BtreeKey(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
  int rc;

  assert( cursorHoldsMutex(pCur) );
  rc = restoreCursorPosition(pCur);
  if( rc==SQLITE_OK ){
    assert( pCur->eState==CURSOR_VALID );
    assert( pCur->iPage>=0 && pCur->apPage[pCur->iPage] );
    if( pCur->apPage[0]->intKey ){
      return SQLITE_CORRUPT_BKPT;
    }
    assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );

    rc = accessPayload(pCur, offset, amt, (unsigned char*)pBuf, 0, 0);
  }
  return rc;
}

/*
** Read part of the data associated with cursor pCur.  Exactly

  }
#endif

  assert( cursorHoldsMutex(pCur) );
  rc = restoreCursorPosition(pCur);
  if( rc==SQLITE_OK ){
    assert( pCur->eState==CURSOR_VALID );
    assert( pCur->iPage>=0 && pCur->apPage[pCur->iPage] );
    assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
    rc = accessPayload(pCur, offset, amt, pBuf, 1, 0);
  }
  return rc;
}

/*
** Return a pointer to payload information from the entry that the 

  int skipKey          /* read beginning at data if this is true */
){
  unsigned char *aPayload;
  MemPage *pPage;
  u32 nKey;
  int nLocal;

  assert( pCur!=0 && pCur->iPage>=0 && pCur->apPage[pCur->iPage]);
  assert( pCur->eState==CURSOR_VALID );
  assert( cursorHoldsMutex(pCur) );
  pPage = pCur->apPage[pCur->iPage];
  assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
  getCellInfo(pCur);
  aPayload = pCur->info.pCell;
  aPayload += pCur->info.nHeader;
  if( pPage->intKey ){
    nKey = 0;
  }else{
    nKey = pCur->info.nKey;

/*
** Move the cursor down to a new child page.  The newPgno argument is the
** page number of the child page to move to.
*/
static int moveToChild(BtCursor *pCur, u32 newPgno){
  int rc;
  int i = pCur->iPage;
  MemPage *pNewPage;

  BtShared *pBt = pCur->pBt;

  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->iPage<BTCURSOR_MAX_DEPTH );
  if( pCur->iPage>=(BTCURSOR_MAX_DEPTH-1) ){
    return SQLITE_CORRUPT_BKPT;
  }
  rc = getAndInitPage(pBt, newPgno, &pNewPage);
  if( rc ) return rc;
  pCur->apPage[i+1] = pNewPage;
  pCur->aiIdx[i+1] = 0;


  pCur->iPage++;

  pCur->info.nSize = 0;
  pCur->validNKey = 0;
  if( pNewPage->nCell<1 ){
    return SQLITE_CORRUPT_BKPT;
  }
  return SQLITE_OK;
}

#ifndef NDEBUG
/*

** Page pParent is an internal (non-leaf) tree page. This function 
** asserts that page number iChild is the left-child if the iIdx'th
** cell in page pParent. Or, if iIdx is equal to the total number of
** cells in pParent, that page number iChild is the right-child of
** the page.

*/

static void assertParentIndex(MemPage *pParent, int iIdx, Pgno iChild){
  assert( iIdx<=pParent->nCell );



  if( iIdx==pParent->nCell ){
    assert( get4byte(&pParent->aData[pParent->hdrOffset+8])==iChild );
  }else{
    assert( get4byte(findCell(pParent, iIdx))==iChild );
  }
}
#else
#  define assertParentIndex(x,y,z) 
#endif

/*
** Move the cursor up to the parent page.
**
** pCur->idx is set to the cell index that contains the pointer
** to the page we are coming from.  If we are coming from the
** right-most child page then pCur->idx is set to one more than
** the largest cell index.
*/
SQLITE_PRIVATE void sqlite3BtreeMoveToParent(BtCursor *pCur){




  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->iPage>0 );
  assert( pCur->apPage[pCur->iPage] );

  assertParentIndex(
    pCur->apPage[pCur->iPage-1], 
    pCur->aiIdx[pCur->iPage-1], 
    pCur->apPage[pCur->iPage]->pgno
  );
  releasePage(pCur->apPage[pCur->iPage]);
  pCur->iPage--;
  pCur->info.nSize = 0;
  pCur->validNKey = 0;


}

/*
** Move the cursor to the root page
*/
static int moveToRoot(BtCursor *pCur){
  MemPage *pRoot;
  int rc = SQLITE_OK;
  Btree *p = pCur->pBtree;
  BtShared *pBt = p->pBt;

  assert( cursorHoldsMutex(pCur) );
  assert( CURSOR_INVALID < CURSOR_REQUIRESEEK );
  assert( CURSOR_VALID   < CURSOR_REQUIRESEEK );
  assert( CURSOR_FAULT   > CURSOR_REQUIRESEEK );
  if( pCur->eState>=CURSOR_REQUIRESEEK ){
    if( pCur->eState==CURSOR_FAULT ){
      return pCur->skip;
    }
    sqlite3BtreeClearCursor(pCur);
  }












  if( pCur->iPage>=0 ){
    int i;
    for(i=1; i<=pCur->iPage; i++){
      releasePage(pCur->apPage[i]);

    }
  }else{
    if( 
      SQLITE_OK!=(rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->apPage[0]))
    ){
      pCur->eState = CURSOR_INVALID;
      return rc;
    }


  }

  pRoot = pCur->apPage[0];
  assert( pRoot->pgno==pCur->pgnoRoot );
  pCur->iPage = 0;
  pCur->aiIdx[0] = 0;
  pCur->info.nSize = 0;
  pCur->atLast = 0;
  pCur->validNKey = 0;

  if( pRoot->nCell==0 && !pRoot->leaf ){
    Pgno subpage;
    assert( pRoot->pgno==1 );
    subpage = get4byte(&pRoot->aData[pRoot->hdrOffset+8]);
    assert( subpage>0 );
    pCur->eState = CURSOR_VALID;
    rc = moveToChild(pCur, subpage);
  }else{
    pCur->eState = ((pRoot->nCell>0)?CURSOR_VALID:CURSOR_INVALID);
  }

  return rc;
}

/*
** Move the cursor down to the left-most leaf entry beneath the
** entry to which it is currently pointing.
**
** The left-most leaf is the one with the smallest key - the first
** in ascending order.
*/
static int moveToLeftmost(BtCursor *pCur){
  Pgno pgno;
  int rc = SQLITE_OK;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState==CURSOR_VALID );
  while( rc==SQLITE_OK && !(pPage = pCur->apPage[pCur->iPage])->leaf ){
    assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
    pgno = get4byte(findCell(pPage, pCur->aiIdx[pCur->iPage]));
    rc = moveToChild(pCur, pgno);
  }
  return rc;
}

/*
** Move the cursor down to the right-most leaf entry beneath the

static int moveToRightmost(BtCursor *pCur){
  Pgno pgno;
  int rc = SQLITE_OK;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pCur->eState==CURSOR_VALID );
  while( rc==SQLITE_OK && !(pPage = pCur->apPage[pCur->iPage])->leaf ){
    pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
    pCur->aiIdx[pCur->iPage] = pPage->nCell;
    rc = moveToChild(pCur, pgno);
  }
  if( rc==SQLITE_OK ){
    pCur->aiIdx[pCur->iPage] = pPage->nCell-1;
    pCur->info.nSize = 0;
    pCur->validNKey = 0;
  }
  return rc;
}

/* Move the cursor to the first entry in the table.  Return SQLITE_OK
** on success.  Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty.
*/
SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor *pCur, int *pRes){
  int rc;

  assert( cursorHoldsMutex(pCur) );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
  rc = moveToRoot(pCur);
  if( rc==SQLITE_OK ){
    if( pCur->eState==CURSOR_INVALID ){
      assert( pCur->apPage[pCur->iPage]->nCell==0 );
      *pRes = 1;
      rc = SQLITE_OK;
    }else{
      assert( pCur->apPage[pCur->iPage]->nCell>0 );
      *pRes = 0;
      rc = moveToLeftmost(pCur);
    }
  }
  return rc;
}

/* Move the cursor to the last entry in the table.  Return SQLITE_OK
** on success.  Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty.
*/
SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
  int rc;
 
  assert( cursorHoldsMutex(pCur) );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
  rc = moveToRoot(pCur);
  if( rc==SQLITE_OK ){
    if( CURSOR_INVALID==pCur->eState ){
      assert( pCur->apPage[pCur->iPage]->nCell==0 );
      *pRes = 1;
    }else{
      assert( pCur->eState==CURSOR_VALID );
      *pRes = 0;
      rc = moveToRightmost(pCur);
      getCellInfo(pCur);
      pCur->atLast = rc==SQLITE_OK;

  int rc;

  assert( cursorHoldsMutex(pCur) );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );

  /* If the cursor is already positioned at the point we are trying
  ** to move to, then just return without doing any work */
  if( pCur->eState==CURSOR_VALID && pCur->validNKey 
   && pCur->apPage[0]->intKey 
  ){
    if( pCur->info.nKey==intKey ){
      *pRes = 0;
      return SQLITE_OK;
    }
    if( pCur->atLast && pCur->info.nKey<intKey ){
      *pRes = -1;
      return SQLITE_OK;
    }
  }

  rc = moveToRoot(pCur);
  if( rc ){
    return rc;
  }
  assert( pCur->apPage[pCur->iPage] );
  assert( pCur->apPage[pCur->iPage]->isInit );
  if( pCur->eState==CURSOR_INVALID ){
    *pRes = -1;
    assert( pCur->apPage[pCur->iPage]->nCell==0 );
    return SQLITE_OK;
  }
  assert( pCur->apPage[0]->intKey || pIdxKey );
  for(;;){
    int lwr, upr;
    Pgno chldPg;
    MemPage *pPage = pCur->apPage[pCur->iPage];
    int c = -1;  /* pRes return if table is empty must be -1 */
    lwr = 0;
    upr = pPage->nCell-1;
    if( !pPage->intKey && pIdxKey==0 ){
      rc = SQLITE_CORRUPT_BKPT;
      goto moveto_finish;
    }
    if( biasRight ){
      pCur->aiIdx[pCur->iPage] = upr;
    }else{
      pCur->aiIdx[pCur->iPage] = (upr+lwr)/2;
    }
    if( lwr<=upr ) for(;;){
      void *pCellKey;
      i64 nCellKey;
      int idx = pCur->aiIdx[pCur->iPage];
      pCur->info.nSize = 0;
      pCur->validNKey = 1;
      if( pPage->intKey ){
        u8 *pCell;
        pCell = findCell(pPage, idx) + pPage->childPtrSize;
        if( pPage->hasData ){
          u32 dummy;
          pCell += getVarint32(pCell, dummy);
        }
        getVarint(pCell, (u64*)&nCellKey);
        if( nCellKey==intKey ){
          c = 0;

          sqlite3_free(pCellKey);
          if( rc ) goto moveto_finish;
        }
      }
      if( c==0 ){
        pCur->info.nKey = nCellKey;
        if( pPage->intKey && !pPage->leaf ){
          lwr = idx;
          upr = lwr - 1;
          break;
        }else{
          if( pRes ) *pRes = 0;
          rc = SQLITE_OK;
          goto moveto_finish;
        }
      }
      if( c<0 ){
        lwr = idx+1;
      }else{
        upr = idx-1;
      }
      if( lwr>upr ){
        pCur->info.nKey = nCellKey;
        break;
      }
      pCur->aiIdx[pCur->iPage] = (lwr+upr)/2;
    }
    assert( lwr==upr+1 );
    assert( pPage->isInit );
    if( pPage->leaf ){
      chldPg = 0;
    }else if( lwr>=pPage->nCell ){
      chldPg = get4byte(&pPage->aData[pPage->hdrOffset+8]);
    }else{
      chldPg = get4byte(findCell(pPage, lwr));
    }
    if( chldPg==0 ){
      assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
      if( pRes ) *pRes = c;
      rc = SQLITE_OK;
      goto moveto_finish;
    }
    pCur->aiIdx[pCur->iPage] = lwr;
    pCur->info.nSize = 0;
    pCur->validNKey = 0;
    rc = moveToChild(pCur, chldPg);
    if( rc ) goto moveto_finish;
  }
moveto_finish:
  return rc;

** Advance the cursor to the next entry in the database.  If
** successful then set *pRes=0.  If the cursor
** was already pointing to the last entry in the database before
** this routine was called, then set *pRes=1.
*/
SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
  int rc;
  int idx;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  rc = restoreCursorPosition(pCur);
  if( rc!=SQLITE_OK ){
    return rc;
  }
  assert( pRes!=0 );

  if( CURSOR_INVALID==pCur->eState ){
    *pRes = 1;
    return SQLITE_OK;
  }
  if( pCur->skip>0 ){
    pCur->skip = 0;
    *pRes = 0;
    return SQLITE_OK;
  }
  pCur->skip = 0;

  pPage = pCur->apPage[pCur->iPage];
  idx = ++pCur->aiIdx[pCur->iPage];
  assert( pPage->isInit );
  assert( idx<=pPage->nCell );


  pCur->info.nSize = 0;
  pCur->validNKey = 0;
  if( idx>=pPage->nCell ){
    if( !pPage->leaf ){
      rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
      if( rc ) return rc;
      rc = moveToLeftmost(pCur);
      *pRes = 0;
      return rc;
    }
    do{
      if( pCur->iPage==0 ){
        *pRes = 1;
        pCur->eState = CURSOR_INVALID;
        return SQLITE_OK;
      }
      sqlite3BtreeMoveToParent(pCur);
      pPage = pCur->apPage[pCur->iPage];
    }while( pCur->aiIdx[pCur->iPage]>=pPage->nCell );
    *pRes = 0;
    if( pPage->intKey ){
      rc = sqlite3BtreeNext(pCur, pRes);
    }else{
      rc = SQLITE_OK;
    }
    return rc;

** Step the cursor to the back to the previous entry in the database.  If
** successful then set *pRes=0.  If the cursor
** was already pointing to the first entry in the database before
** this routine was called, then set *pRes=1.
*/
SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
  int rc;

  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  rc = restoreCursorPosition(pCur);
  if( rc!=SQLITE_OK ){
    return rc;
  }
  pCur->atLast = 0;
  if( CURSOR_INVALID==pCur->eState ){
    *pRes = 1;
    return SQLITE_OK;
  }
  if( pCur->skip<0 ){
    pCur->skip = 0;
    *pRes = 0;
    return SQLITE_OK;
  }
  pCur->skip = 0;

  pPage = pCur->apPage[pCur->iPage];
  assert( pPage->isInit );

  if( !pPage->leaf ){
    int idx = pCur->aiIdx[pCur->iPage];
    rc = moveToChild(pCur, get4byte(findCell(pPage, idx)));
    if( rc ){
      return rc;
    }
    rc = moveToRightmost(pCur);
  }else{
    while( pCur->aiIdx[pCur->iPage]==0 ){
      if( pCur->iPage==0 ){
        pCur->eState = CURSOR_INVALID;
        *pRes = 1;
        return SQLITE_OK;
      }
      sqlite3BtreeMoveToParent(pCur);

    }

    pCur->info.nSize = 0;
    pCur->validNKey = 0;

    pCur->aiIdx[pCur->iPage]--;
    pPage = pCur->apPage[pCur->iPage];
    if( pPage->intKey && !pPage->leaf ){
      rc = sqlite3BtreePrevious(pCur, pRes);
    }else{
      rc = SQLITE_OK;
    }
  }
  *pRes = 0;

  }

  assert( *pPgno!=PENDING_BYTE_PAGE(pBt) );

end_allocate_page:
  releasePage(pTrunk);
  releasePage(pPrevTrunk);
  if( rc==SQLITE_OK && sqlite3PagerPageRefcount((*ppPage)->pDbPage)>1 ){

    releasePage(*ppPage);
    return SQLITE_CORRUPT_BKPT;


  }
  return rc;
}

/*
** Add a page of the database file to the freelist.
**
** sqlite3PagerUnref() is NOT called for pPage.
*/
static int freePage(MemPage *pPage){
  BtShared *pBt = pPage->pBt;
  MemPage *pPage1 = pBt->pPage1;
  int rc, n, k;

  /* Prepare the page for freeing */
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->pgno>1 );
  pPage->isInit = 0;



  /* Increment the free page count on pPage1 */
  rc = sqlite3PagerWrite(pPage1->pDbPage);
  if( rc ) return rc;
  n = get4byte(&pPage1->aData[36]);
  put4byte(&pPage1->aData[36], n+1);

      pSrc = pData;
    }
  }
  releasePage(pToRelease);
  return SQLITE_OK;
}

































































































/*
** Remove the i-th cell from pPage.  This routine effects pPage only.
** The cell content is not freed or deallocated.  It is assumed that
** the cell content has been copied someplace else.  This routine just
** removes the reference to the cell from pPage.
**
** "sz" must be the number of bytes in the cell.

  for(i=idx+1; i<pPage->nCell; i++, ptr+=2){
    ptr[0] = ptr[2];
    ptr[1] = ptr[3];
  }
  pPage->nCell--;
  put2byte(&data[pPage->hdrOffset+3], pPage->nCell);
  pPage->nFree += 2;

}

/*
** Insert a new cell on pPage at cell index "i".  pCell points to the
** content of the cell.
**
** If the cell content will fit on the page, then put it there.  If it

    memcpy(&data[idx+nSkip], pCell+nSkip, sz-nSkip);
    for(j=end-2, ptr=&data[j]; j>ins; j-=2, ptr-=2){
      ptr[0] = ptr[-2];
      ptr[1] = ptr[-1];
    }
    put2byte(&data[ins], idx);
    put2byte(&data[hdr+3], pPage->nCell);

#ifndef SQLITE_OMIT_AUTOVACUUM
    if( pPage->pBt->autoVacuum ){
      /* The cell may contain a pointer to an overflow page. If so, write
      ** the entry for the overflow page into the pointer map.
      */
      CellInfo info;
      sqlite3BtreeParseCellPtr(pPage, pCell, &info);

** in exchange for a larger degradation in INSERT and UPDATE performance.
** The value of NN appears to give the best results overall.
*/
#define NN 1             /* Number of neighbors on either side of pPage */
#define NB (NN*2+1)      /* Total pages involved in the balance */

/* Forward reference */
static int balance(BtCursor*, int);

#ifndef SQLITE_OMIT_QUICKBALANCE
/*
** This version of balance() handles the common special case where
** a new entry is being inserted on the extreme right-end of the
** tree, in other words, when the new entry will become the largest
** entry in the tree.
**
** Instead of trying balance the 3 right-most leaf pages, just add
** a new page to the right-hand side and put the one new entry in
** that page.  This leaves the right side of the tree somewhat
** unbalanced.  But odds are that we will be inserting new entries
** at the end soon afterwards so the nearly empty page will quickly
** fill up.  On average.
**
** pPage is the leaf page which is the right-most page in the tree.
** pParent is its parent.  pPage must have a single overflow entry
** which is also the right-most entry on the page.
*/
static int balance_quick(BtCursor *pCur){
  int rc;
  MemPage *pNew = 0;
  Pgno pgnoNew;
  u8 *pCell;
  u16 szCell;
  CellInfo info;
  MemPage *pPage = pCur->apPage[pCur->iPage];
  MemPage *pParent = pCur->apPage[pCur->iPage-1];
  BtShared *pBt = pPage->pBt;
  int parentIdx = pParent->nCell;   /* pParent new divider cell index */
  int parentSize;                   /* Size of new divider cell */
  u8 parentCell[64];                /* Space for the new divider cell */

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );

  /* Allocate a new page. Insert the overflow cell from pPage
  ** into it. Then remove the overflow cell from pPage.
  */
  rc = allocateBtreePage(pBt, &pNew, &pgnoNew, 0, 0);
  if( rc==SQLITE_OK ){
    pCell = pPage->aOvfl[0].pCell;
    szCell = cellSizePtr(pPage, pCell);
    zeroPage(pNew, pPage->aData[0]);
    assemblePage(pNew, 1, &pCell, &szCell);
    pPage->nOverflow = 0;
  




    /* pPage is currently the right-child of pParent. Change this
    ** so that the right-child is the new page allocated above and
    ** pPage is the next-to-right child. 
    **
    ** Ignore the return value of the call to fillInCell(). fillInCell()
    ** may only return other than SQLITE_OK if it is required to allocate
    ** one or more overflow pages. Since an internal table B-Tree cell 

  ** not important, as they will be recalculated when the page is rolled
  ** back. But here, in balance_quick(), it is possible that pPage has 
  ** not yet been marked dirty or written into the journal file. Therefore
  ** it will not be rolled back and so it is important to make sure that
  ** the page data and contents of MemPage are consistent.
  */
  pPage->isInit = 0;
  sqlite3BtreeInitPage(pPage);


  /* If everything else succeeded, balance the parent page, in 
  ** case the divider cell inserted caused it to become overfull.
  */
  if( rc==SQLITE_OK ){
    releasePage(pPage);
    pCur->iPage--;
    rc = balance(pCur, 0);
  }
  return rc;
}
#endif /* SQLITE_OMIT_QUICKBALANCE */

/*
** This routine redistributes Cells on pPage and up to NN*2 siblings

** might become overfull or underfull.  If that happens, then this routine
** is called recursively on the parent.
**
** If this routine fails for any reason, it might leave the database
** in a corrupted state.  So if this routine fails, the database should
** be rolled back.
*/
static int balance_nonroot(BtCursor *pCur){
  MemPage *pPage;              /* The over or underfull page to balance */
  MemPage *pParent;            /* The parent of pPage */
  BtShared *pBt;               /* The whole database */
  int nCell = 0;               /* Number of cells in apCell[] */
  int nMaxCells = 0;           /* Allocated size of apCell, szCell, aFrom. */
  int nOld;                    /* Number of pages in apOld[] */
  int nNew;                    /* Number of pages in apNew[] */
  int nDiv;                    /* Number of cells in apDiv[] */

  u8 **apCell = 0;             /* All cells begin balanced */
  u16 *szCell;                 /* Local size of all cells in apCell[] */
  u8 *aCopy[NB];         /* Space for holding data of apCopy[] */
  u8 *aSpace1;           /* Space for copies of dividers cells before balance */
  u8 *aSpace2 = 0;       /* Space for overflow dividers cells after balance */
  u8 *aFrom = 0;

  pPage = pCur->apPage[pCur->iPage];
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  VVA_ONLY( pCur->pagesShuffled = 1 );

  /* 
  ** Find the parent page.
  */
  assert( pCur->iPage>0 );
  assert( pPage->isInit );
  assert( sqlite3PagerIswriteable(pPage->pDbPage) || pPage->nOverflow==1 );
  pBt = pPage->pBt;
  pParent = pCur->apPage[pCur->iPage-1];
  assert( pParent );
  if( SQLITE_OK!=(rc = sqlite3PagerWrite(pParent->pDbPage)) ){
    return rc;
  }

  TRACE(("BALANCE: begin page %d child of %d\n", pPage->pgno, pParent->pgno));

#ifndef SQLITE_OMIT_QUICKBALANCE
  /*
  ** A special case:  If a new entry has just been inserted into a
  ** table (that is, a btree with integer keys and all data at the leaves)
  ** and the new entry is the right-most entry in the tree (it has the
  ** largest key) then use the special balance_quick() routine for
  ** balancing.  balance_quick() is much faster and results in a tighter
  ** packing of data in the common case.
  */
  if( pPage->leaf &&
      pPage->intKey &&
      pPage->nOverflow==1 &&
      pPage->aOvfl[0].idx==pPage->nCell &&
      pParent->pgno!=1 &&
      get4byte(&pParent->aData[pParent->hdrOffset+8])==pPage->pgno
  ){
    assert( pPage->intKey );
    /*
    ** TODO: Check the siblings to the left of pPage. It may be that
    ** they are not full and no new page is required.
    */
    return balance_quick(pCur);
  }
#endif

  if( SQLITE_OK!=(rc = sqlite3PagerWrite(pPage->pDbPage)) ){
    return rc;
  }

  /*
  ** Find the cell in the parent page whose left child points back
  ** to pPage.  The "idx" variable is the index of that cell.  If pPage
  ** is the rightmost child of pParent then set idx to pParent->nCell 
  */


  idx = pCur->aiIdx[pCur->iPage-1];


  assertParentIndex(pParent, idx, pPage->pgno);









  /*
  ** Initialize variables so that it will be safe to jump
  ** directly to balance_cleanup at any moment.
  */
  nOld = nNew = 0;


  /*
  ** Find sibling pages to pPage and the cells in pParent that divide
  ** the siblings.  An attempt is made to find NN siblings on either
  ** side of pPage.  More siblings are taken from one side, however, if
  ** pPage there are fewer than NN siblings on the other side.  If pParent
  ** has NB or fewer children then all children of pParent are taken.

      assert( !pParent->leaf );
      pgnoOld[i] = get4byte(apDiv[i]);
    }else if( k==pParent->nCell ){
      pgnoOld[i] = get4byte(&pParent->aData[pParent->hdrOffset+8]);
    }else{
      break;
    }
    rc = getAndInitPage(pBt, pgnoOld[i], &apOld[i]);
    if( rc ) goto balance_cleanup;
    /* apOld[i]->idxParent = k; */
    apCopy[i] = 0;
    assert( i==nOld );
    nOld++;
    nMaxCells += 1+apOld[i]->nCell+apOld[i]->nOverflow;
  }

  /* Make nMaxCells a multiple of 4 in order to preserve 8-byte

    put4byte(&pParent->aData[pParent->hdrOffset+8], pgnoNew[nNew-1]);
  }else{
    /* Right-most sibling is the left child of the first entry in pParent
    ** past the right-most divider entry */
    put4byte(findOverflowCell(pParent, nxDiv), pgnoNew[nNew-1]);
  }











  /*
  ** Balance the parent page.  Note that the current page (pPage) might
  ** have been added to the freelist so it might no longer be initialized.
  ** But the parent page will always be initialized.
  */
  assert( pParent->isInit );
  sqlite3ScratchFree(apCell);
  apCell = 0;
  releasePage(pPage);
  pCur->iPage--;
  rc = balance(pCur, 0);
  
  /*
  ** Cleanup before returning.
  */
balance_cleanup:
  sqlite3PageFree(aSpace2);
  sqlite3ScratchFree(apCell);
  for(i=0; i<nOld; i++){
    releasePage(apOld[i]);
  }
  for(i=0; i<nNew; i++){
    releasePage(apNew[i]);
  }

  /* releasePage(pParent); */
  TRACE(("BALANCE: finished with %d: old=%d new=%d cells=%d\n",
          pPage->pgno, nOld, nNew, nCell));

  return rc;
}

/*
** This routine is called for the root page of a btree when the root
** page contains no cells.  This is an opportunity to make the tree
** shallower by one level.
*/
static int balance_shallower(BtCursor *pCur){
  MemPage *pPage;              /* Root page of B-Tree */
  MemPage *pChild;             /* The only child page of pPage */
  Pgno pgnoChild;              /* Page number for pChild */
  int rc = SQLITE_OK;          /* Return code from subprocedures */
  BtShared *pBt;                  /* The main BTree structure */
  int mxCellPerPage;           /* Maximum number of cells per page */
  u8 **apCell;                 /* All cells from pages being balanced */
  u16 *szCell;                 /* Local size of all cells */

  assert( pCur->iPage==0 );
  pPage = pCur->apPage[0];

  assert( pPage->nCell==0 );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  pBt = pPage->pBt;
  mxCellPerPage = MX_CELL(pBt);
  apCell = sqlite3Malloc( mxCellPerPage*(sizeof(u8*)+sizeof(u16)) );
  if( apCell==0 ) return SQLITE_NOMEM;
  szCell = (u16*)&apCell[mxCellPerPage];

    ** its child (due to the 100 byte header that occurs at the beginning
    ** of the database fle), so it might not be able to hold all of the 
    ** information currently contained in the child.  If this is the 
    ** case, then do not do the transfer.  Leave page 1 empty except
    ** for the right-pointer to the child page.  The child page becomes
    ** the virtual root of the tree.
    */
    VVA_ONLY( pCur->pagesShuffled = 1 );
    pgnoChild = get4byte(&pPage->aData[pPage->hdrOffset+8]);
    assert( pgnoChild>0 );
    assert( pgnoChild<=pagerPagecount(pPage->pBt->pPager) );
    rc = sqlite3BtreeGetPage(pPage->pBt, pgnoChild, &pChild, 0);
    if( rc ) goto end_shallow_balance;
    if( pPage->pgno==1 ){
      rc = sqlite3BtreeInitPage(pChild);
      if( rc ) goto end_shallow_balance;
      assert( pChild->nOverflow==0 );
      if( pChild->nFree>=100 ){
        /* The child information will fit on the root page, so do the
        ** copy */
        int i;
        zeroPage(pPage, pChild->aData[0]);

        /* The child has more information that will fit on the root.
        ** The tree is already balanced.  Do nothing. */
        TRACE(("BALANCE: child %d will not fit on page 1\n", pChild->pgno));
      }
    }else{
      memcpy(pPage->aData, pChild->aData, pPage->pBt->usableSize);
      pPage->isInit = 0;

      rc = sqlite3BtreeInitPage(pPage);
      assert( rc==SQLITE_OK );
      freePage(pChild);
      TRACE(("BALANCE: transfer child %d into root %d\n",
              pChild->pgno, pPage->pgno));
    }

    assert( pPage->nOverflow==0 );
    if( ISAUTOVACUUM ){


      rc = setChildPtrmaps(pPage);




    }
    releasePage(pChild);
  }
end_shallow_balance:
  sqlite3_free(apCell);
  return rc;
}


/*
** The root page is overfull
**
** When this happens, Create a new child page and copy the
** contents of the root into the child.  Then make the root
** page an empty page with rightChild pointing to the new
** child.   Finally, call balance_internal() on the new child
** to cause it to split.
*/
static int balance_deeper(BtCursor *pCur){
  int rc;             /* Return value from subprocedures */
  MemPage *pPage;     /* Pointer to the root page */
  MemPage *pChild;    /* Pointer to a new child page */
  Pgno pgnoChild;     /* Page number of the new child page */
  BtShared *pBt;         /* The BTree */
  int usableSize;     /* Total usable size of a page */
  u8 *data;           /* Content of the parent page */
  u8 *cdata;          /* Content of the child page */
  int hdr;            /* Offset to page header in parent */
  int cbrk;           /* Offset to content of first cell in parent */

  assert( pCur->iPage==0 );
  assert( pCur->apPage[0]->nOverflow>0 );

  VVA_ONLY( pCur->pagesShuffled = 1 );
  pPage = pCur->apPage[0];
  pBt = pPage->pBt;
  assert( sqlite3_mutex_held(pBt->mutex) );
  rc = allocateBtreePage(pBt, &pChild, &pgnoChild, pPage->pgno, 0);
  if( rc ) return rc;
  assert( sqlite3PagerIswriteable(pChild->pDbPage) );
  usableSize = pBt->usableSize;
  data = pPage->aData;
  hdr = pPage->hdrOffset;
  cbrk = get2byte(&data[hdr+5]);
  cdata = pChild->aData;
  memcpy(cdata, &data[hdr], pPage->cellOffset+2*pPage->nCell-hdr);
  memcpy(&cdata[cbrk], &data[cbrk], usableSize-cbrk);
  
  rc = sqlite3BtreeInitPage(pChild);
  if( rc==SQLITE_OK ){
    int nCopy = pPage->nOverflow*sizeof(pPage->aOvfl[0]);
    memcpy(pChild->aOvfl, pPage->aOvfl, nCopy);
    pChild->nOverflow = pPage->nOverflow;
    if( pChild->nOverflow ){
      pChild->nFree = 0;
    }
    assert( pChild->nCell==pPage->nCell );
    zeroPage(pPage, pChild->aData[0] & ~PTF_LEAF);
    put4byte(&pPage->aData[pPage->hdrOffset+8], pgnoChild);
    TRACE(("BALANCE: copy root %d into %d\n", pPage->pgno, pChild->pgno));
    if( ISAUTOVACUUM ){

      rc = ptrmapPut(pBt, pChild->pgno, PTRMAP_BTREE, pPage->pgno);



      if( rc==SQLITE_OK ){

        rc = setChildPtrmaps(pChild);
      }
    }

  }

  if( rc==SQLITE_OK ){
    pCur->iPage++;
    pCur->apPage[1] = pChild;
    pCur->aiIdx[0] = 0;
    rc = balance_nonroot(pCur);
  }else{
    releasePage(pChild);
  }



  return rc;
}

/*
** The page that pCur currently points to has just been modified in
** some way. This function figures out if this modification means the
** tree needs to be balanced, and if so calls the appropriate balancing 
** routine.
** 
** Parameter isInsert is true if a new cell was just inserted into the
** page, or false otherwise.
*/
static int balance(BtCursor *pCur, int isInsert){
  int rc = SQLITE_OK;
  MemPage *pPage = pCur->apPage[pCur->iPage];

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  if( pCur->iPage==0 ){
    rc = sqlite3PagerWrite(pPage->pDbPage);
    if( rc==SQLITE_OK && pPage->nOverflow>0 ){
      rc = balance_deeper(pCur);
    }
    if( rc==SQLITE_OK && pPage->nCell==0 ){
      rc = balance_shallower(pCur);
    }
  }else{
    if( pPage->nOverflow>0 || 
        (!isInsert && pPage->nFree>pPage->pBt->usableSize*2/3) ){
      rc = balance_nonroot(pCur);
    }
  }
  return rc;
}

/*
** This routine checks all cursors that point to table pgnoRoot.

  const void *pData, int nData,  /* The data of the new record */
  int nZero,                     /* Number of extra 0 bytes to append to data */
  int appendBias                 /* True if this is likely an append */
){
  int rc;
  int loc;
  int szNew;
  int idx;
  MemPage *pPage;
  Btree *p = pCur->pBtree;
  BtShared *pBt = p->pBt;
  unsigned char *oldCell;
  unsigned char *newCell = 0;

  assert( cursorHoldsMutex(pCur) );

    return SQLITE_LOCKED; /* The table pCur points to has a read lock */
  }
  if( pCur->eState==CURSOR_FAULT ){
    return pCur->skip;
  }

  /* Save the positions of any other cursors open on this table */
  sqlite3BtreeClearCursor(pCur);
  if( 
    SQLITE_OK!=(rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur)) ||
    SQLITE_OK!=(rc = sqlite3BtreeMoveto(pCur, pKey, nKey, appendBias, &loc))
  ){
    return rc;
  }

  pPage = pCur->apPage[pCur->iPage];
  assert( pPage->intKey || nKey>=0 );
  assert( pPage->leaf || !pPage->intKey );
  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
          pCur->pgnoRoot, nKey, nData, pPage->pgno,
          loc==0 ? "overwrite" : "new entry"));
  assert( pPage->isInit );
  allocateTempSpace(pBt);
  newCell = pBt->pTmpSpace;
  if( newCell==0 ) return SQLITE_NOMEM;
  rc = fillInCell(pPage, newCell, pKey, nKey, pData, nData, nZero, &szNew);
  if( rc ) goto end_insert;
  assert( szNew==cellSizePtr(pPage, newCell) );
  assert( szNew<=MX_CELL_SIZE(pBt) );
  idx = pCur->aiIdx[pCur->iPage];
  if( loc==0 && CURSOR_VALID==pCur->eState ){
    u16 szOld;
    assert( idx<pPage->nCell );
    rc = sqlite3PagerWrite(pPage->pDbPage);
    if( rc ){
      goto end_insert;
    }
    oldCell = findCell(pPage, idx);
    if( !pPage->leaf ){
      memcpy(newCell, oldCell, 4);
    }
    szOld = cellSizePtr(pPage, oldCell);
    rc = clearCell(pPage, oldCell);
    if( rc ) goto end_insert;
    dropCell(pPage, idx, szOld);
  }else if( loc<0 && pPage->nCell>0 ){
    assert( pPage->leaf );
    idx = ++pCur->aiIdx[pCur->iPage];
    pCur->info.nSize = 0;
    pCur->validNKey = 0;
  }else{
    assert( pPage->leaf );
  }
  rc = insertCell(pPage, idx, newCell, szNew, 0, 0);
  if( rc!=SQLITE_OK ) goto end_insert;
  rc = balance(pCur, 1);
  if( rc==SQLITE_OK ){
    moveToRoot(pCur);
  }
end_insert:
  return rc;
}

/*
** Delete the entry that the cursor is pointing to.  The cursor
** is left pointing at a arbitrary location.
*/
SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor *pCur){
  MemPage *pPage = pCur->apPage[pCur->iPage];
  int idx;
  unsigned char *pCell;
  int rc;
  Pgno pgnoChild = 0;
  Btree *p = pCur->pBtree;
  BtShared *pBt = p->pBt;

  assert( cursorHoldsMutex(pCur) );
  assert( pPage->isInit );
  if( pBt->inTransaction!=TRANS_WRITE ){
    /* Must start a transaction before doing a delete */
    rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
    return rc;
  }
  assert( !pBt->readOnly );
  if( pCur->eState==CURSOR_FAULT ){
    return pCur->skip;
  }
  if( pCur->aiIdx[pCur->iPage]>=pPage->nCell ){
    return SQLITE_ERROR;  /* The cursor is not pointing to anything */
  }
  if( !pCur->wrFlag ){
    return SQLITE_PERM;   /* Did not open this cursor for writing */
  }
  if( checkReadLocks(pCur->pBtree, pCur->pgnoRoot, pCur, pCur->info.nKey) ){
    return SQLITE_LOCKED; /* The table pCur points to has a read lock */

    return rc;
  }

  /* Locate the cell within its page and leave pCell pointing to the
  ** data. The clearCell() call frees any overflow pages associated with the
  ** cell. The cell itself is still intact.
  */
  idx = pCur->aiIdx[pCur->iPage];
  pCell = findCell(pPage, idx);
  if( !pPage->leaf ){
    pgnoChild = get4byte(pCell);
  }
  rc = clearCell(pPage, pCell);
  if( rc ){
    return rc;
  }

  if( !pPage->leaf ){
    /*
    ** The entry we are about to delete is not a leaf so if we do not
    ** do something we will leave a hole on an internal page.
    ** We have to fill the hole by moving in a cell from a leaf.  The
    ** next Cell after the one to be deleted is guaranteed to exist and
    ** to be a leaf so we can use it.
    */
    BtCursor leafCur;
    MemPage *pLeafPage;

    unsigned char *pNext;
    int notUsed;
    unsigned char *tempCell = 0;
    assert( !pPage->intKey );
    sqlite3BtreeGetTempCursor(pCur, &leafCur);
    rc = sqlite3BtreeNext(&leafCur, &notUsed);
    if( rc==SQLITE_OK ){
      assert( leafCur.aiIdx[leafCur.iPage]==0 );
      pLeafPage = leafCur.apPage[leafCur.iPage];
      rc = sqlite3PagerWrite(pLeafPage->pDbPage);
    }
    if( rc==SQLITE_OK ){
      int leafCursorInvalid = 0;
      u16 szNext;
      TRACE(("DELETE: table=%d delete internal from %d replace from leaf %d\n",
         pCur->pgnoRoot, pPage->pgno, pLeafPage->pgno));
      dropCell(pPage, idx, cellSizePtr(pPage, pCell));
      pNext = findCell(pLeafPage, 0);
      szNext = cellSizePtr(pLeafPage, pNext);
      assert( MX_CELL_SIZE(pBt)>=szNext+4 );
      allocateTempSpace(pBt);
      tempCell = pBt->pTmpSpace;
      if( tempCell==0 ){
        rc = SQLITE_NOMEM;
      }
      if( rc==SQLITE_OK ){
        rc = insertCell(pPage, idx, pNext-4, szNext+4, tempCell, 0);
      }


      /* The "if" statement in the next code block is critical.  The
      ** slightest error in that statement would allow SQLite to operate
      ** correctly most of the time but produce very rare failures.  To
      ** guard against this, the following macros help to verify that
      ** the "if" statement is well tested.
      */
      testcase( pPage->nOverflow==0 && pPage->nFree<pBt->usableSize*2/3 
                 && pLeafPage->nFree+2+szNext > pBt->usableSize*2/3 );
      testcase( pPage->nOverflow==0 && pPage->nFree==pBt->usableSize*2/3 
                 && pLeafPage->nFree+2+szNext > pBt->usableSize*2/3 );
      testcase( pPage->nOverflow==0 && pPage->nFree==pBt->usableSize*2/3+1 
                 && pLeafPage->nFree+2+szNext > pBt->usableSize*2/3 );
      testcase( pPage->nOverflow>0 && pPage->nFree<=pBt->usableSize*2/3
                 && pLeafPage->nFree+2+szNext > pBt->usableSize*2/3 );
      testcase( (pPage->nOverflow>0 || (pPage->nFree > pBt->usableSize*2/3))
                 && pLeafPage->nFree+2+szNext == pBt->usableSize*2/3 );


      if( (pPage->nOverflow>0 || (pPage->nFree > pBt->usableSize*2/3)) &&
          (pLeafPage->nFree+2+szNext > pBt->usableSize*2/3)
      ){
        /* This branch is taken if the internal node is now either overflowing
        ** or underfull and the leaf node will be underfull after the just cell 
        ** copied to the internal node is deleted from it. This is a special
        ** case because the call to balance() to correct the internal node
        ** may change the tree structure and invalidate the contents of
        ** the leafCur.apPage[] and leafCur.aiIdx[] arrays, which will be
        ** used by the balance() required to correct the underfull leaf
        ** node.
        **
        ** The formula used in the expression above are based on facets of
        ** the SQLite file-format that do not change over time.
        */
        testcase( pPage->nFree==pBt->usableSize*2/3+1 );
        testcase( pLeafPage->nFree+2+szNext==pBt->usableSize*2/3+1 );
        leafCursorInvalid = 1;
      }        

      if( rc==SQLITE_OK ){
        put4byte(findOverflowCell(pPage, idx), pgnoChild);
        VVA_ONLY( pCur->pagesShuffled = 0 );
        rc = balance(pCur, 0);
      }

      if( rc==SQLITE_OK && leafCursorInvalid ){
        /* The leaf-node is now underfull and so the tree needs to be 
        ** rebalanced. However, the balance() operation on the internal
        ** node above may have modified the structure of the B-Tree and
        ** so the current contents of leafCur.apPage[] and leafCur.aiIdx[]
        ** may not be trusted.
        **
        ** It is not possible to copy the ancestry from pCur, as the same
        ** balance() call has invalidated the pCur->apPage[] and aiIdx[]
        ** arrays. 
        **
        ** The call to saveCursorPosition() below internally saves the 
        ** key that leafCur is currently pointing to. Currently, there
        ** are two copies of that key in the tree - one here on the leaf
        ** page and one on some internal node in the tree. The copy on
        ** the leaf node is always the next key in tree-order after the 
        ** copy on the internal node. So, the call to sqlite3BtreeNext()
        ** calls restoreCursorPosition() to point the cursor to the copy
        ** stored on the internal node, then advances to the next entry,
        ** which happens to be the copy of the key on the internal node.
        ** Net effect: leafCur is pointing back to the duplicate cell
        ** that needs to be removed, and the leafCur.apPage[] and
        ** leafCur.aiIdx[] arrays are correct.
        */
        VVA_ONLY( Pgno leafPgno = pLeafPage->pgno );
        rc = saveCursorPosition(&leafCur);
        if( rc==SQLITE_OK ){
          rc = sqlite3BtreeNext(&leafCur, &notUsed);
        }
        pLeafPage = leafCur.apPage[leafCur.iPage];
        assert( pLeafPage->pgno==leafPgno );
        assert( leafCur.aiIdx[leafCur.iPage]==0 );
      }

      if( rc==SQLITE_OK ){
        dropCell(pLeafPage, 0, szNext);
        VVA_ONLY( leafCur.pagesShuffled = 0 );
        rc = balance(&leafCur, 0);
        assert( leafCursorInvalid || !leafCur.pagesShuffled
                                   || !pCur->pagesShuffled );
      }
    }
    sqlite3BtreeReleaseTempCursor(&leafCur);
  }else{
    TRACE(("DELETE: table=%d delete from leaf %d\n",
       pCur->pgnoRoot, pPage->pgno));
    dropCell(pPage, idx, cellSizePtr(pPage, pCell));
    rc = balance(pCur, 0);
  }
  if( rc==SQLITE_OK ){
    moveToRoot(pCur);
  }
  return rc;
}

  int i;

  assert( sqlite3_mutex_held(pBt->mutex) );
  if( pgno>pagerPagecount(pBt->pPager) ){
    return SQLITE_CORRUPT_BKPT;
  }

  rc = getAndInitPage(pBt, pgno, &pPage);
  if( rc ) goto cleardatabasepage_out;
  for(i=0; i<pPage->nCell; i++){
    pCell = findCell(pPage, i);
    if( !pPage->leaf ){
      rc = clearDatabasePage(pBt, get4byte(pCell), pPage, 1);
      if( rc ) goto cleardatabasepage_out;
    }

*/
SQLITE_PRIVATE int sqlite3BtreeFlags(BtCursor *pCur){
  /* TODO: What about CURSOR_REQUIRESEEK state? Probably need to call
  ** restoreCursorPosition() here.
  */
  MemPage *pPage;
  restoreCursorPosition(pCur);
  pPage = pCur->apPage[pCur->iPage];
  assert( cursorHoldsMutex(pCur) );
  assert( pPage->pBt==pCur->pBt );
  return pPage ? pPage->aData[pPage->hdrOffset] : 0;
}


/*

  if( iPage==0 ) return 0;
  if( checkRef(pCheck, iPage, zParentContext) ) return 0;
  if( (rc = sqlite3BtreeGetPage(pBt, (Pgno)iPage, &pPage, 0))!=0 ){
    checkAppendMsg(pCheck, zContext,
       "unable to get the page. error code=%d", rc);
    return 0;
  }
  if( (rc = sqlite3BtreeInitPage(pPage))!=0 ){
    checkAppendMsg(pCheck, zContext, 
                   "sqlite3BtreeInitPage() returns error code %d", rc);
    releasePage(pPage);
    return 0;
  }

  /* Check out all the cells.

            nCopy = nToPageSize;
          }else{
            zTo += (((iFrom-1)*nFromPageSize) - (i-1)*nToPageSize);
            nCopy = nFromPageSize;
          }

          memcpy(zTo, zFrom, nCopy);
          sqlite3PagerUnref(pFromPage);
        }
      }

      if( pToPage ){
        MemPage *p = (MemPage *)sqlite3PagerGetExtra(pToPage);
        p->isInit = 0;
        sqlite3PagerUnref(pToPage);

    return SQLITE_READONLY;
  }
  assert( !pCsr->pBt->readOnly 
          && pCsr->pBt->inTransaction==TRANS_WRITE );
  if( checkReadLocks(pCsr->pBtree, pCsr->pgnoRoot, pCsr, 0) ){
    return SQLITE_LOCKED; /* The table pCur points to has a read lock */
  }
  if( pCsr->eState==CURSOR_INVALID || !pCsr->apPage[pCsr->iPage]->intKey ){
    return SQLITE_ERROR;
  }

  return accessPayload(pCsr, offset, amt, (unsigned char *)z, 0, 1);
}

/* 

**
*************************************************************************
** This file contains code used for creating, destroying, and populating
** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.)  Prior
** to version 2.8.7, all this code was combined into the vdbe.c source file.
** But that file was getting too big so this subroutines were split out.
**
** $Id: vdbeaux.c,v 1.412 2008/10/11 17:51:39 danielk1977 Exp $
*/



/*
** When debugging the code generator in a symbolic debugger, one can
** set the sqlite3VdbeAddopTrace to 1 and all opcodes will be printed

  /* If the VDBE has be run even partially, then transfer the error code
  ** and error message from the VDBE into the main database structure.  But
  ** if the VDBE has just been set to run but has not actually executed any
  ** instructions yet, leave the main database error information unchanged.
  */
  if( p->pc>=0 ){
    if( p->zErrMsg ){
      sqlite3BeginBenignMalloc();
      sqlite3ValueSetStr(db->pErr,-1,p->zErrMsg,SQLITE_UTF8,SQLITE_TRANSIENT);
      sqlite3EndBenignMalloc();
      db->errCode = p->rc;
      sqlite3DbFree(db, p->zErrMsg);
      p->zErrMsg = 0;
    }else if( p->rc ){
      sqlite3Error(db, p->rc, 0);
    }else{
      sqlite3Error(db, SQLITE_OK, 0);

**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code use to implement APIs that are part of the
** VDBE.
**
** $Id: vdbeapi.c,v 1.147 2008/10/13 10:37:50 danielk1977 Exp $
*/

#if 0 && defined(SQLITE_ENABLE_MEMORY_MANAGEMENT)
/*
** The following structure contains pointers to the end points of a
** doubly-linked list of all compiled SQL statements that may be holding
** buffers eligible for release when the sqlite3_release_memory() interface is

#else       /* !SQLITE_ENABLE_MEMORY_MANAGEMENT */
  #define stmtLruRemove(x)
  #define stmtLruAdd(x)
  #define vdbeReprepare(x) sqlite3Reprepare(x)
#endif


#ifndef SQLITE_OMIT_DEPRECATED
/*
** Return TRUE (non-zero) of the statement supplied as an argument needs
** to be recompiled.  A statement needs to be recompiled whenever the
** execution environment changes in a way that would alter the program
** that sqlite3_prepare() generates.  For example, if new functions or
** collating sequences are registered or if an authorizer function is
** added or changed.
*/
SQLITE_API int sqlite3_expired(sqlite3_stmt *pStmt){
  Vdbe *p = (Vdbe*)pStmt;
  return p==0 || p->expired;
}
#endif

/*
** The following routine destroys a virtual machine that is created by
** the sqlite3_compile() routine. The integer returned is an SQLITE_
** success/failure code that describes the result of executing the virtual
** machine.
**
** This routine sets the error code and string returned by
** sqlite3_errcode(), sqlite3_errmsg() and sqlite3_errmsg16().
*/
SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt){
  int rc;
  if( pStmt==0 ){
    rc = SQLITE_OK;
  }else{
    Vdbe *v = (Vdbe*)pStmt;
#if SQLITE_THREADSAFE
    sqlite3_mutex *mutex = v->db->mutex;
#endif
    sqlite3_mutex_enter(mutex);
    stmtLruRemove(v);
    rc = sqlite3VdbeFinalize(v);
    sqlite3_mutex_leave(mutex);
  }

/*
** Set all the parameters in the compiled SQL statement to NULL.
*/
SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt *pStmt){
  int i;
  int rc = SQLITE_OK;
  Vdbe *p = (Vdbe*)pStmt;
#if SQLITE_THREADSAFE
  sqlite3_mutex *mutex = ((Vdbe*)pStmt)->db->mutex;
#endif
  sqlite3_mutex_enter(mutex);
  for(i=0; i<p->nVar; i++){
    sqlite3VdbeMemRelease(&p->aVar[i]);
    p->aVar[i].flags = MEM_Null;
  }

failed:
  if( xDelete ){
    xDelete(pAux);
  }
}

#ifndef SQLITE_OMIT_DEPRECATED
/*
** Return the number of times the Step function of a aggregate has been 
** called.
**
** This function is deprecated.  Do not use it for new code.  It is
** provide only to avoid breaking legacy code.  New aggregate function
** implementations should keep their own counts within their aggregate
** context.
*/
SQLITE_API int sqlite3_aggregate_count(sqlite3_context *p){
  assert( p && p->pFunc && p->pFunc->xStep );
  return p->pMem->n;
}
#endif

/*
** Return the number of columns in the result set for the statement pStmt.
*/
SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt){
  Vdbe *pVm = (Vdbe *)pStmt;
  return pVm ? pVm->nResColumn : 0;

}
SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt *pStmt, int i){
  const unsigned char *val = sqlite3_value_text( columnMem(pStmt,i) );
  columnMallocFailure(pStmt);
  return val;
}
SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt *pStmt, int i){
  Mem *pOut = columnMem(pStmt, i);
  if( pOut->flags&MEM_Static ){
    pOut->flags &= ~MEM_Static;
    pOut->flags |= MEM_Ephem;
  }
  columnMallocFailure(pStmt);
  return (sqlite3_value *)pOut;
}
#ifndef SQLITE_OMIT_UTF16
SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt *pStmt, int i){
  const void *val = sqlite3_value_text16( columnMem(pStmt,i) );
  columnMallocFailure(pStmt);
  return val;
}

** 
** Routines used to attach values to wildcards in a compiled SQL statement.
*/
/*
** Unbind the value bound to variable i in virtual machine p. This is the 
** the same as binding a NULL value to the column. If the "i" parameter is
** out of range, then SQLITE_RANGE is returned. Othewise SQLITE_OK.
**
** A successful evaluation of this routine acquires the mutex on p.
** the mutex is released if any kind of error occurs.
**
** The error code stored in database p->db is overwritten with the return
** value in any case.
*/
static int vdbeUnbind(Vdbe *p, int i){
  Mem *pVar;
  if( p==0 ) return SQLITE_MISUSE;
  sqlite3_mutex_enter(p->db->mutex);
  if( p->magic!=VDBE_MAGIC_RUN || p->pc>=0 ){
    sqlite3Error(p->db, SQLITE_MISUSE, 0);
    sqlite3_mutex_leave(p->db->mutex);
    return SQLITE_MISUSE;
  }
  if( i<1 || i>p->nVar ){
    sqlite3Error(p->db, SQLITE_RANGE, 0);
    sqlite3_mutex_leave(p->db->mutex);
    return SQLITE_RANGE;
  }
  i--;
  pVar = &p->aVar[i];
  sqlite3VdbeMemRelease(pVar);
  pVar->flags = MEM_Null;
  sqlite3Error(p->db, SQLITE_OK, 0);

  void (*xDel)(void*),   /* Destructor for the data */
  int encoding           /* Encoding for the data */
){
  Vdbe *p = (Vdbe *)pStmt;
  Mem *pVar;
  int rc;





  rc = vdbeUnbind(p, i);
  if( rc==SQLITE_OK ){
    if( zData!=0 ){
      pVar = &p->aVar[i-1];
      rc = sqlite3VdbeMemSetStr(pVar, zData, nData, encoding, xDel);
      if( rc==SQLITE_OK && encoding!=0 ){
        rc = sqlite3VdbeChangeEncoding(pVar, ENC(p->db));
      }
      sqlite3Error(p->db, rc, 0);
      rc = sqlite3ApiExit(p->db, rc);
    }
    sqlite3_mutex_leave(p->db->mutex);
  }
  return rc;
}


/*
** Bind a blob value to an SQL statement variable.
*/
SQLITE_API int sqlite3_bind_blob(
  sqlite3_stmt *pStmt, 
  int i, 
  const void *zData, 
  int nData, 
  void (*xDel)(void*)
){
  return bindText(pStmt, i, zData, nData, xDel, 0);
}
SQLITE_API int sqlite3_bind_double(sqlite3_stmt *pStmt, int i, double rValue){
  int rc;
  Vdbe *p = (Vdbe *)pStmt;

  rc = vdbeUnbind(p, i);
  if( rc==SQLITE_OK ){
    sqlite3VdbeMemSetDouble(&p->aVar[i-1], rValue);

    sqlite3_mutex_leave(p->db->mutex);
  }
  return rc;
}
SQLITE_API int sqlite3_bind_int(sqlite3_stmt *p, int i, int iValue){
  return sqlite3_bind_int64(p, i, (i64)iValue);
}
SQLITE_API int sqlite3_bind_int64(sqlite3_stmt *pStmt, int i, sqlite_int64 iValue){
  int rc;
  Vdbe *p = (Vdbe *)pStmt;

  rc = vdbeUnbind(p, i);
  if( rc==SQLITE_OK ){
    sqlite3VdbeMemSetInt64(&p->aVar[i-1], iValue);

    sqlite3_mutex_leave(p->db->mutex);
  }
  return rc;
}
SQLITE_API int sqlite3_bind_null(sqlite3_stmt *pStmt, int i){
  int rc;
  Vdbe *p = (Vdbe*)pStmt;

  rc = vdbeUnbind(p, i);
  if( rc==SQLITE_OK ){
    sqlite3_mutex_leave(p->db->mutex);
  }
  return rc;
}
SQLITE_API int sqlite3_bind_text( 
  sqlite3_stmt *pStmt, 
  int i, 
  const char *zData, 
  int nData, 

){
  return bindText(pStmt, i, zData, nData, xDel, SQLITE_UTF16NATIVE);
}
#endif /* SQLITE_OMIT_UTF16 */
SQLITE_API int sqlite3_bind_value(sqlite3_stmt *pStmt, int i, const sqlite3_value *pValue){
  int rc;
  Vdbe *p = (Vdbe *)pStmt;

  rc = vdbeUnbind(p, i);
  if( rc==SQLITE_OK ){
    rc = sqlite3VdbeMemCopy(&p->aVar[i-1], pValue);
    if( rc==SQLITE_OK ){
      rc = sqlite3VdbeChangeEncoding(&p->aVar[i-1], ENC(p->db));
    }
    sqlite3_mutex_leave(p->db->mutex);
  }
  rc = sqlite3ApiExit(p->db, rc);

  return rc;
}
SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt *pStmt, int i, int n){
  int rc;
  Vdbe *p = (Vdbe *)pStmt;

  rc = vdbeUnbind(p, i);
  if( rc==SQLITE_OK ){
    sqlite3VdbeMemSetZeroBlob(&p->aVar[i-1], n);

    sqlite3_mutex_leave(p->db->mutex);
  }
  return rc;
}

/*
** Return the number of wildcards that can be potentially bound to.
** This routine is added to support DBD::SQLite.  
*/

    sqlite3VdbeMemMove(&pTo->aVar[i], &pFrom->aVar[i]);
  }
  sqlite3_mutex_leave(pTo->db->mutex);
  assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
  return rc;
}

#ifndef SQLITE_OMIT_DEPRECATED
/*
** Deprecated external interface.  Internal/core SQLite code
** should call sqlite3TransferBindings.
*/
SQLITE_API int sqlite3_transfer_bindings(sqlite3_stmt *pFromStmt, sqlite3_stmt *pToStmt){
  return sqlite3TransferBindings(pFromStmt, pToStmt);
}
#endif

/*
** Return the sqlite3* database handle to which the prepared statement given
** in the argument belongs.  This is the same database handle that was
** the first argument to the sqlite3_prepare() that was used to create
** the statement in the first place.
*/

    pNext = (sqlite3_stmt*)pDb->pVdbe;
  }else{
    pNext = (sqlite3_stmt*)((Vdbe*)pStmt)->pNext;
  }
  sqlite3_mutex_leave(pDb->mutex);
  return pNext;
}

/*
** Return the value of a status counter for a prepared statement
*/
SQLITE_API int sqlite3_stmt_status(sqlite3_stmt *pStmt, int op, int resetFlag){
  Vdbe *pVdbe = (Vdbe*)pStmt;
  int v = pVdbe->aCounter[op-1];
  if( resetFlag ) pVdbe->aCounter[op-1] = 0;
  return v;
}

/************** End of vdbeapi.c *********************************************/
/************** Begin file vdbe.c ********************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.782 2008/10/08 17:58:49 danielk1977 Exp $
*/

/*
** The following global variable is incremented every time a cursor
** moves, either by the OP_MoveXX, OP_Next, or OP_Prev opcodes.  The test
** procedures use this information to make sure that indices are
** working correctly.  This variable has no function other than to

*/
#if defined(SQLITE_TEST) && !defined(SQLITE_OMIT_BUILTIN_TEST)
# define UPDATE_MAX_BLOBSIZE(P)  updateMaxBlobsize(P)
#else
# define UPDATE_MAX_BLOBSIZE(P)
#endif







/*
** Convert the given register into a string if it isn't one
** already. Return non-zero if a malloc() fails.
*/
#define Stringify(P, enc) \
   if(((P)->flags&(MEM_Str|MEM_Blob))==0 && sqlite3VdbeMemStringify(P,enc)) \
     { goto no_mem; }

  ** the pointer to ctx.s so in case the user-function can use
  ** the already allocated buffer instead of allocating a new one.
  */
  sqlite3VdbeMemMove(&ctx.s, pOut);
  MemSetTypeFlag(&ctx.s, MEM_Null);

  ctx.isError = 0;
  if( ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
    assert( pOp>p->aOp );
    assert( pOp[-1].p4type==P4_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    ctx.pColl = pOp[-1].p4.pColl;
  }
  if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
  (*ctx.pFunc->xFunc)(&ctx, n, apVal);

    /* If we have read more header data than was contained in the header,
    ** or if the end of the last field appears to be past the end of the
    ** record, or if the end of the last field appears to be before the end
    ** of the record (when all fields present), then we must be dealing 
    ** with a corrupt database.
    */
    if( zIdx>zEndHdr || offset>payloadSize 
     || (zIdx==zEndHdr && offset!=payloadSize) ){
      rc = SQLITE_CORRUPT_BKPT;
      goto op_column_out;
    }
  }

  /* Get the column information. If aOffset[p2] is non-zero, then 
  ** deserialize the value from the record. If aOffset[p2] is zero,

  Cursor *pC;

  assert( i>=0 && i<p->nCursor );
  pC = p->apCsr[i];
  assert( pC!=0 );
  pC->nullRow = 1;
  pC->rowidIsValid = 0;
  if( pC->pCursor ){
    sqlite3BtreeClearCursor(pC->pCursor);
  }
  break;
}

/* Opcode: Last P1 P2 * * *
**
** The next use of the Rowid or Column or Next instruction for P1 
** will refer to the last entry in the database table or index.

** correctly optimizing out sorts.
*/
case OP_Sort: {        /* jump */
#ifdef SQLITE_TEST
  sqlite3_sort_count++;
  sqlite3_search_count--;
#endif
  p->aCounter[SQLITE_STMTSTATUS_SORT-1]++;
  /* Fall through into OP_Rewind */
}
/* Opcode: Rewind P1 P2 * * *
**
** The next use of the Rowid or Column or Next instruction for P1 
** will refer to the first entry in the database table or index.
** If the table or index is empty and P2>0, then jump immediately to P2.

  assert( pC->deferredMoveto==0 );
  rc = pOp->opcode==OP_Next ? sqlite3BtreeNext(pCrsr, &res) :
                              sqlite3BtreePrevious(pCrsr, &res);
  pC->nullRow = res;
  pC->cacheStatus = CACHE_STALE;
  if( res==0 ){
    pc = pOp->p2 - 1;
    if( pOp->p5 ) p->aCounter[pOp->p5-1]++;
#ifdef SQLITE_TEST
    sqlite3_search_count++;
#endif
  }
  pC->rowidIsValid = 0;
  break;
}

      assert( pC->deferredMoveto==0 );
      pC->cacheStatus = CACHE_STALE;
    }
  }
  break;
}

/* Opcode: IdxDelete P1 P2 P3 * *
**
** The content of P3 registers starting at register P2 form
** an unpacked index key. This opcode removes that entry from the 
** index opened by cursor P1.
*/
case OP_IdxDelete: {
  int i = pOp->p1;

  ctx.s.flags = MEM_Null;
  ctx.s.z = 0;
  ctx.s.zMalloc = 0;
  ctx.s.xDel = 0;
  ctx.s.db = db;
  ctx.isError = 0;
  ctx.pColl = 0;
  if( ctx.pFunc->flags & SQLITE_FUNC_NEEDCOLL ){
    assert( pOp>p->aOp );
    assert( pOp[-1].p4type==P4_COLLSEQ );
    assert( pOp[-1].opcode==OP_CollSeq );
    ctx.pColl = pOp[-1].p4.pColl;
  }
  (ctx.pFunc->xStep)(&ctx, n, apVal);
  if( ctx.isError ){

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code used to implement incremental BLOB I/O.
**
** $Id: vdbeblob.c,v 1.26 2008/10/02 14:49:02 danielk1977 Exp $
*/


#ifndef SQLITE_OMIT_INCRBLOB

/*
** Valid sqlite3_blob* handles point to Incrblob structures.

  int (*xCall)(BtCursor*, u32, u32, void*)
){
  int rc;
  Incrblob *p = (Incrblob *)pBlob;
  Vdbe *v;
  sqlite3 *db = p->db;  

  sqlite3_mutex_enter(db->mutex);
  v = (Vdbe*)p->pStmt;

  if( n<0 || iOffset<0 || (iOffset+n)>p->nByte ){
    /* Request is out of range. Return a transient error. */

    rc = SQLITE_ERROR;

    sqlite3Error(db, SQLITE_ERROR, 0);
  } else if( v==0 ){
    /* If there is no statement handle, then the blob-handle has
    ** already been invalidated. Return SQLITE_ABORT in this case.
    */


    rc = SQLITE_ABORT;
  }else{
    /* Call either BtreeData() or BtreePutData(). If SQLITE_ABORT is
    ** returned, clean-up the statement handle.
    */
    assert( db == v->db );
    sqlite3BtreeEnterCursor(p->pCsr);

**
*************************************************************************
**
** This file contains routines used for walking the parser tree and
** resolve all identifiers by associating them with a particular
** table and column.
**
** $Id: resolve.c,v 1.9 2008/10/11 16:47:36 drh Exp $
*/

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

    }
    pDup->iTable = pEList->a[iCol].iAlias;
  }
  if( pExpr->flags & EP_ExpCollate ){
    pDup->pColl = pExpr->pColl;
    pDup->flags |= EP_ExpCollate;
  }
  sqlite3ExprClear(db, pExpr);

  memcpy(pExpr, pDup, sizeof(*pExpr));
  sqlite3DbFree(db, pDup);
}

/*
** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up
** that name in the set of source tables in pSrcList and make the pExpr 

    int i;
    for(i=0; i<pNC->pSrcList->nSrc; i++){
      assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab);
    }
  }
#endif
  switch( pExpr->op ){

#if defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY)
    /* The special operator TK_ROW means use the rowid for the first
    ** column in the FROM clause.  This is used by the LIMIT and ORDER BY
    ** clause processing on UPDATE and DELETE statements.
    */
    case TK_ROW: {
      SrcList *pSrcList = pNC->pSrcList;
      struct SrcList_item *pItem;
      assert( pSrcList && pSrcList->nSrc==1 );
      pItem = pSrcList->a; 
      pExpr->op = TK_COLUMN;
      pExpr->pTab = pItem->pTab;
      pExpr->iTable = pItem->iCursor;
      pExpr->iColumn = -1;
      pExpr->affinity = SQLITE_AFF_INTEGER;
      break;
    }
#endif /* defined(SQLITE_ENABLE_UPDATE_DELETE_LIMIT) && !defined(SQLITE_OMIT_SUBQUERY) */

    /* A lone identifier is the name of a column.
    */
    case TK_ID: {
      lookupName(pParse, 0, 0, &pExpr->token, pNC, pExpr);
      return WRC_Prune;
    }
  

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.399 2008/10/11 16:47:36 drh Exp $
*/

/*
** Return the 'affinity' of the expression pExpr if any.
**
** If pExpr is a column, a reference to a column via an 'AS' alias,
** or a sub-select with a column as the return value, then the 

  } 
  if( !pParse->nErr && pParse->nVar>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){
    sqlite3ErrorMsg(pParse, "too many SQL variables");
  }
}

/*
** Clear an expression structure without deleting the structure itself.
** Substructure is deleted.
*/
SQLITE_PRIVATE void sqlite3ExprClear(sqlite3 *db, Expr *p){

  if( p->span.dyn ) sqlite3DbFree(db, (char*)p->span.z);
  if( p->token.dyn ) sqlite3DbFree(db, (char*)p->token.z);
  sqlite3ExprDelete(db, p->pLeft);
  sqlite3ExprDelete(db, p->pRight);
  sqlite3ExprListDelete(db, p->pList);
  sqlite3SelectDelete(db, p->pSelect);
}

/*
** Recursively delete an expression tree.
*/
SQLITE_PRIVATE void sqlite3ExprDelete(sqlite3 *db, Expr *p){
  if( p==0 ) return;
  sqlite3ExprClear(db, p);
  sqlite3DbFree(db, p);
}

/*
** The Expr.token field might be a string literal that is quoted.
** If so, remove the quotation marks.
*/

    Table *pTab;
    pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);
    pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
    pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);
    pNewItem->jointype = pOldItem->jointype;
    pNewItem->iCursor = pOldItem->iCursor;
    pNewItem->isPopulated = pOldItem->isPopulated;
    pNewItem->zIndex = sqlite3DbStrDup(db, pOldItem->zIndex);
    pNewItem->notIndexed = pOldItem->notIndexed;
    pNewItem->pIndex = pOldItem->pIndex;
    pTab = pNewItem->pTab = pOldItem->pTab;
    if( pTab ){
      pTab->nRef++;
    }
    pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect);
    pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn);
    pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);

        }
      }
    }
  }

  if( eType==0 ){
    int rMayHaveNull = 0;
    eType = IN_INDEX_EPH;
    if( prNotFound ){
      *prNotFound = rMayHaveNull = ++pParse->nMem;
    }else if( pX->pLeft->iColumn<0 && pX->pSelect==0 ){
      eType = IN_INDEX_ROWID;
    }
    sqlite3CodeSubselect(pParse, pX, rMayHaveNull, eType==IN_INDEX_ROWID);

  }else{
    pX->iTable = iTab;
  }
  return eType;
}
#endif

/*
** Generate code for scalar subqueries used as an expression
** and IN operators.  Examples:
**
**     (SELECT a FROM b)          -- subquery
**     EXISTS (SELECT a FROM b)   -- EXISTS subquery
**     x IN (4,5,11)              -- IN operator with list on right-hand side
**     x IN (SELECT a FROM b)     -- IN operator with subquery on the right
**
** The pExpr parameter describes the expression that contains the IN
** operator or subquery.
**
** If parameter isRowid is non-zero, then expression pExpr is guaranteed
** to be of the form "<rowid> IN (?, ?, ?)", where <rowid> is a reference
** to some integer key column of a table B-Tree. In this case, use an
** intkey B-Tree to store the set of IN(...) values instead of the usual
** (slower) variable length keys B-Tree.
*/
#ifndef SQLITE_OMIT_SUBQUERY
SQLITE_PRIVATE void sqlite3CodeSubselect(
  Parse *pParse, 
  Expr *pExpr, 
  int rMayHaveNull,
  int isRowid
){
  int testAddr = 0;                       /* One-time test address */
  Vdbe *v = sqlite3GetVdbe(pParse);
  if( v==0 ) return;


  /* This code must be run in its entirety every time it is encountered
  ** if any of the following is true:

  }

  switch( pExpr->op ){
    case TK_IN: {
      char affinity;
      KeyInfo keyInfo;
      int addr;        /* Address of OP_OpenEphemeral instruction */
      Expr *pLeft = pExpr->pLeft;

      if( rMayHaveNull ){
        sqlite3VdbeAddOp2(v, OP_Null, 0, rMayHaveNull);
      }

      affinity = sqlite3ExprAffinity(pLeft);

      /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
      ** expression it is handled the same way. A virtual table is 
      ** filled with single-field index keys representing the results
      ** from the SELECT or the <exprlist>.
      **
      ** If the 'x' expression is a column value, or the SELECT...
      ** statement returns a column value, then the affinity of that
      ** column is used to build the index keys. If both 'x' and the
      ** SELECT... statement are columns, then numeric affinity is used
      ** if either column has NUMERIC or INTEGER affinity. If neither
      ** 'x' nor the SELECT... statement are columns, then numeric affinity
      ** is used.
      */
      pExpr->iTable = pParse->nTab++;
      addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, !isRowid);
      memset(&keyInfo, 0, sizeof(keyInfo));
      keyInfo.nField = 1;

      if( pExpr->pSelect ){
        /* Case 1:     expr IN (SELECT ...)
        **
        ** Generate code to write the results of the select into the temporary
        ** table allocated and opened above.
        */
        SelectDest dest;
        ExprList *pEList;

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

          affinity = SQLITE_AFF_NONE;
        }
        keyInfo.aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft);

        /* Loop through each expression in <exprlist>. */
        r1 = sqlite3GetTempReg(pParse);
        r2 = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp2(v, OP_Null, 0, r2);
        for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){
          Expr *pE2 = pItem->pExpr;

          /* If the expression is not constant then we will need to
          ** disable the test that was generated above that makes sure
          ** this code only executes once.  Because for a non-constant
          ** expression we need to rerun this code each time.
          */
          if( testAddr && !sqlite3ExprIsConstant(pE2) ){
            sqlite3VdbeChangeToNoop(v, testAddr-1, 2);
            testAddr = 0;
          }

          /* Evaluate the expression and insert it into the temp table */
          pParse->disableColCache++;
          r3 = sqlite3ExprCodeTarget(pParse, pE2, r1);
          assert( pParse->disableColCache>0 );
          pParse->disableColCache--;

          if( isRowid ){
            sqlite3VdbeAddOp2(v, OP_MustBeInt, r3, sqlite3VdbeCurrentAddr(v)+2);
            sqlite3VdbeAddOp3(v, OP_Insert, pExpr->iTable, r2, r3);
          }else{
            sqlite3VdbeAddOp4(v, OP_MakeRecord, r3, 1, r2, &affinity, 1);
            sqlite3ExprCacheAffinityChange(pParse, r3, 1);
            sqlite3VdbeAddOp2(v, OP_IdxInsert, pExpr->iTable, r2);
          }
        }
        sqlite3ReleaseTempReg(pParse, r1);
        sqlite3ReleaseTempReg(pParse, r2);
      }
      if( !isRowid ){
        sqlite3VdbeChangeP4(v, addr, (void *)&keyInfo, P4_KEYINFO);
      }
      break;
    }

    case TK_EXISTS:
    case TK_SELECT: {
      /* This has to be a scalar SELECT.  Generate code to put the
      ** value of this select in a memory cell and record the number

        pDef = sqlite3VtabOverloadFunction(db, pDef, nExpr, pList->a[0].pExpr);
      }
#endif
      for(i=0; i<nExpr && i<32; i++){
        if( sqlite3ExprIsConstant(pList->a[i].pExpr) ){
          constMask |= (1<<i);
        }
        if( (pDef->flags & SQLITE_FUNC_NEEDCOLL)!=0 && !pColl ){
          pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr);
        }
      }
      if( pDef->flags & SQLITE_FUNC_NEEDCOLL ){
        if( !pColl ) pColl = db->pDfltColl; 
        sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
      }
      sqlite3VdbeAddOp4(v, OP_Function, constMask, r1, target,
                        (char*)pDef, P4_FUNCDEF);
      sqlite3VdbeChangeP5(v, nExpr);
      if( nExpr ){
        sqlite3ReleaseTempRange(pParse, r1, nExpr);
      }
      sqlite3ExprCacheAffinityChange(pParse, r1, nExpr);
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case TK_EXISTS:
    case TK_SELECT: {
      testcase( op==TK_EXISTS );
      testcase( op==TK_SELECT );
      if( pExpr->iColumn==0 ){
        sqlite3CodeSubselect(pParse, pExpr, 0, 0);
      }
      inReg = pExpr->iColumn;
      break;
    }
    case TK_IN: {
      int rNotFound = 0;
      int rMayHaveNull = 0;

                             nullRecord, P4_STATIC);
          j4 = sqlite3VdbeAddOp3(v, OP_Found, pExpr->iTable, 0, rMayHaveNull);
          sqlite3VdbeAddOp2(v, OP_Integer, 0, rNotFound);
          sqlite3VdbeJumpHere(v, j4);
          sqlite3VdbeJumpHere(v, j3);

          /* Copy the value of register rNotFound (which is either NULL or 0)
          ** into the target register. This will be the result of the
          ** expression.
          */
          sqlite3VdbeAddOp2(v, OP_Copy, rNotFound, target);
        }
      }
      sqlite3VdbeJumpHere(v, j2);
      sqlite3VdbeJumpHere(v, j5);

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.498 2008/10/06 16:18:40 danielk1977 Exp $
*/

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Initialize the pParse structure as needed.
*/
SQLITE_PRIVATE void sqlite3BeginParse(Parse *pParse, int explainFlag){

    Token *pTemp = pDatabase;
    pDatabase = pTable;
    pTable = pTemp;
  }
  pItem->zName = sqlite3NameFromToken(db, pTable);
  pItem->zDatabase = sqlite3NameFromToken(db, pDatabase);
  pItem->iCursor = -1;

  pList->nSrc++;
  return pList;
}

/*
** Assign cursors to all tables in a SrcList
*/

  int i;
  struct SrcList_item *pItem;
  if( pList==0 ) return;
  for(pItem=pList->a, i=0; i<pList->nSrc; i++, pItem++){
    sqlite3DbFree(db, pItem->zDatabase);
    sqlite3DbFree(db, pItem->zName);
    sqlite3DbFree(db, pItem->zAlias);
    sqlite3DbFree(db, pItem->zIndex);
    sqlite3DeleteTable(pItem->pTab);
    sqlite3SelectDelete(db, pItem->pSelect);
    sqlite3ExprDelete(db, pItem->pOn);
    sqlite3IdListDelete(db, pItem->pUsing);
  }
  sqlite3DbFree(db, pList);
}

    pItem->zAlias = sqlite3NameFromToken(db, pAlias);
  }
  pItem->pSelect = pSubquery;
  pItem->pOn = pOn;
  pItem->pUsing = pUsing;
  return p;
}

/*
** Add an INDEXED BY or NOT INDEXED clause to the most recently added 
** element of the source-list passed as the second argument.
*/
SQLITE_PRIVATE void sqlite3SrcListIndexedBy(Parse *pParse, SrcList *p, Token *pIndexedBy){
  if( pIndexedBy && p && p->nSrc>0 ){
    struct SrcList_item *pItem = &p->a[p->nSrc-1];
    assert( pItem->notIndexed==0 && pItem->zIndex==0 );
    if( pIndexedBy->n==1 && !pIndexedBy->z ){
      /* A "NOT INDEXED" clause was supplied. See parse.y 
      ** construct "indexed_opt" for details. */
      pItem->notIndexed = 1;
    }else{
      pItem->zIndex = sqlite3NameFromToken(pParse->db, pIndexedBy);
    }
  }
}

/*
** When building up a FROM clause in the parser, the join operator
** is initially attached to the left operand.  But the code generator
** expects the join operator to be on the right operand.  This routine
** Shifts all join operators from left to right for an entire FROM
** clause.

**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains functions used to access the internal hash tables
** of user defined functions and collation sequences.
**
** $Id: callback.c,v 1.32 2008/10/10 17:41:29 drh Exp $
*/


/*
** Invoke the 'collation needed' callback to request a collation sequence
** in the database text encoding of name zName, length nName.
** If the collation sequence

  Hash temp1;
  Hash temp2;
  HashElem *pElem;
  Schema *pSchema = (Schema *)p;

  temp1 = pSchema->tblHash;
  temp2 = pSchema->trigHash;
  sqlite3HashInit(&pSchema->trigHash, 0);
  sqlite3HashClear(&pSchema->aFKey);
  sqlite3HashClear(&pSchema->idxHash);
  for(pElem=sqliteHashFirst(&temp2); pElem; pElem=sqliteHashNext(pElem)){
    sqlite3DeleteTrigger(0, (Trigger*)sqliteHashData(pElem));
  }
  sqlite3HashClear(&temp2);
  sqlite3HashInit(&pSchema->tblHash, 0);
  for(pElem=sqliteHashFirst(&temp1); pElem; pElem=sqliteHashNext(pElem)){
    Table *pTab = sqliteHashData(pElem);
    sqlite3DeleteTable(pTab);
  }
  sqlite3HashClear(&temp1);
  pSchema->pSeqTab = 0;
  pSchema->flags &= ~DB_SchemaLoaded;