SQLite

**    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 1.39 2008/09/02 10:22:01 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
#include <ctype.h>

/*
** This routine runs when the memory allocator sees that the

  return SQLITE_OK;
#endif
}

/*
** State information local to the memory allocation subsystem.
*/
static SQLITE_WSD struct Mem0Global {
  sqlite3_mutex *mutex;         /* Mutex to serialize access */

  /*
  ** The alarm callback and its arguments.  The mem0.mutex lock will
  ** be held while the callback is running.  Recursive calls into
  ** the memory subsystem are allowed, but no new callbacks will be
  ** issued.  The alarmBusy variable is set to prevent recursive

  */
  u32 *aScratchFree;
  u32 *aPageFree;

  /* Number of free pages for scratch and page-cache memory */
  u32 nScratchFree;
  u32 nPageFree;
} mem0 = {};

#define mem0 GLOBAL(struct Mem0Global, mem0)

/*
** Initialize the memory allocation subsystem.
*/
int sqlite3MallocInit(void){
  if( sqlite3GlobalConfig.m.xMalloc==0 ){
    sqlite3MemSetDefault();

** implementations. Once sqlite3_initialize() has been called,
** the amount of memory available to SQLite is fixed and cannot
** be changed.
**
** This version of the memory allocation subsystem is included
** in the build only if SQLITE_ENABLE_MEMSYS3 is defined.
**
** $Id: mem3.c,v 1.22 2008/09/02 10:22:01 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** This version of the memory allocator is only built into the library
** SQLITE_ENABLE_MEMSYS3 is defined. Defining this symbol does not
** mean that the library will use a memory-pool by default, just that

/*
** All of the static variables used by this module are collected
** into a single structure named "mem3".  This is to keep the
** static variables organized and to reduce namespace pollution
** when this module is combined with other in the amalgamation.
*/
static SQLITE_WSD struct Mem3Global {
  /*
  ** True if we are evaluating an out-of-memory callback.
  */
  int alarmBusy;
  
  /*
  ** Mutex to control access to the memory allocation subsystem.

  /*
  ** Memory available for allocation. nPool is the size of the array
  ** (in Mem3Blocks) pointed to by aPool less 2.
  */
  u32 nPool;
  Mem3Block *aPool;
} mem3 = {};

#define mem3 GLOBAL(struct Mem3Global, mem3)

/*
** Unlink the chunk at mem3.aPool[i] from list it is currently
** on.  *pRoot is the list that i is a member of.
*/
static void memsys3UnlinkFromList(u32 i, u32 *pRoot){
  u32 next = mem3.aPool[i].u.list.next;

/*
** Open the file indicated and write a log of all unfreed memory 
** allocations into that log.
*/

void sqlite3Memsys3Dump(const char *zFilename){
#ifdef SQLITE_DEBUG
  FILE *out;
  int i, j;
  u32 size;
  if( zFilename==0 || zFilename[0]==0 ){
    out = stdout;
  }else{
    out = fopen(zFilename, "w");

  fprintf(out, "mxUsed=%d\n", mem3.nPool*8 - mem3.mnMaster*8);
  sqlite3_mutex_leave(mem3.mutex);
  if( out==stdout ){
    fflush(stdout);
  }else{
    fclose(out);
  }

#endif
}

/*
** This routine is the only routine in this file with external 
** linkage.
**
** Populate the low-level memory allocation function pointers in
** sqlite3GlobalConfig.m with pointers to the routines in this file. The

** implementations. Once sqlite3_initialize() has been called,
** the amount of memory available to SQLite is fixed and cannot
** be changed.
**
** This version of the memory allocation subsystem is included
** in the build only if SQLITE_ENABLE_MEMSYS5 is defined.
**
** $Id: mem5.c,v 1.13 2008/09/02 10:22:01 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** This version of the memory allocator is used only when 
** SQLITE_POW2_MEMORY_SIZE is defined.
*/

/*
** All of the static variables used by this module are collected
** into a single structure named "mem5".  This is to keep the
** static variables organized and to reduce namespace pollution
** when this module is combined with other in the amalgamation.
*/
static SQLITE_WSD struct Mem5Global {
  /*
  ** The alarm callback and its arguments.  The mem5.mutex lock will
  ** be held while the callback is running.  Recursive calls into
  ** the memory subsystem are allowed, but no new callbacks will be
  ** issued.  The alarmBusy variable is set to prevent recursive
  ** callbacks.
  */

  /*
  ** Memory available for allocation
  */
  int nAtom;       /* Smallest possible allocation in bytes */
  int nBlock;      /* Number of nAtom sized blocks in zPool */
  u8 *zPool;
} mem5 = {};

#define mem5 GLOBAL(struct Mem5Global, mem5)

#define MEM5LINK(idx) ((Mem5Link *)(&mem5.zPool[(idx)*mem5.nAtom]))

/*
** Unlink the chunk at mem5.aPool[i] from list it is currently
** on.  It should be found on mem5.aiFreelist[iLogsize].
*/

** the same as that used by mem5.c. 
**
** This strategy is designed to prevent the default memory allocation
** system (usually the system malloc) from suffering from heap 
** fragmentation. On some systems, heap fragmentation can cause a 
** significant real-time slowdown.
**
** $Id: mem6.c,v 1.9 2008/09/02 10:22:01 danielk1977 Exp $
*/

#ifdef SQLITE_ENABLE_MEMSYS6

#include "sqliteInt.h"

/*

  int nAtom;       /* Smallest possible allocation in bytes */
  int nBlock;      /* Number of nAtom sized blocks in zPool */
  u8 *zPool;       /* Pointer to memory chunk from which allocations are made */
};

#define MEM6LINK(idx) ((Mem6Link *)(&pChunk->zPool[(idx)*pChunk->nAtom]))

static SQLITE_WSD struct Mem6Global {
  int nMinAlloc;                  /* Minimum allowed allocation size */
  int nThreshold;                 /* Allocs larger than this go to malloc() */
  int nLogThreshold;              /* log2 of (nThreshold/nMinAlloc) */
  sqlite3_mutex *mutex;
  Mem6Chunk *pChunk;              /* Singly linked list of all memory chunks */
} mem6 = {};

#define mem6 GLOBAL(struct Mem6Global, mem6)

/*
** Unlink the chunk at pChunk->aPool[i] from list it is currently
** on.  It should be found on pChunk->aiFreelist[iLogsize].
*/
static void memsys6Unlink(Mem6Chunk *pChunk, int i, int iLogsize){
  int next, prev;

**    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 1.121 2008/09/02 10:22:01 danielk1977 Exp $
*/
#define _SQLITE_OS_C_ 1
#include "sqliteInt.h"
#undef _SQLITE_OS_C_

/*
** The default SQLite sqlite3_vfs implementations do not allocate

  sqlite3_free(pFile);
  return rc;
}

/*
** The list of all registered VFS implementations.
*/
static SQLITE_WSD sqlite3_vfs *vfsList = 0;
#define vfsList GLOBAL(sqlite3_vfs *, vfsList)

/*
** Locate a VFS by name.  If no name is given, simply return the
** first VFS on the list.
*/
sqlite3_vfs *sqlite3_vfs_find(const char *zVfs){
  sqlite3_vfs *pVfs = 0;