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Overview
Comment:Modify the memory allocation system in mem3.c so to fit in with the new sqlite3_mem_methods scheme. At this point it only "mostly" works. (CVS 5297)
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SHA1: 3febef548fb1c314336fe4bc359d72a4fe84e84e
User & Date: danielk1977 2008-06-24 19:02:55
Context
2008-06-24
22:50
OS/2 fixes for pre-C99 compilers and a return code correction in os2Access(). (CVS 5298) check-in: 3241a3bd user: pweilbacher tags: trunk
19:02
Modify the memory allocation system in mem3.c so to fit in with the new sqlite3_mem_methods scheme. At this point it only "mostly" works. (CVS 5297) check-in: 3febef54 user: danielk1977 tags: trunk
15:39
Add a few extra tests to select9.test. (CVS 5296) check-in: 37b084fd user: danielk1977 tags: trunk
Changes
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Changes to src/main.c.

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**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.458 2008/06/23 14:15:53 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

#ifdef SQLITE_ENABLE_FTS3
# include "fts3.h"
#endif
................................................................................
    }
    case SQLITE_CONFIG_SERIALIZED: {
      /* Enable all mutexing */
      sqlite3Config.bCoreMutex = 1;
      sqlite3Config.bFullMutex = 1;
      break;
    }








    case SQLITE_CONFIG_MALLOC: {
      /* Specify an alternative malloc implementation */
      sqlite3Config.m = *va_arg(ap, sqlite3_mem_methods*);
      break;
    }
    case SQLITE_CONFIG_GETMALLOC: {
      /* Specify an alternative malloc implementation */
      if( sqlite3Config.m.xMalloc==0 ) sqlite3MemSetDefault();
      *va_arg(ap, sqlite3_mem_methods*) = sqlite3Config.m;
      break;
    }
    case SQLITE_CONFIG_MUTEX: {
      /* Specify an alternative mutex implementation */
      sqlite3Config.mutex = *va_arg(ap, sqlite3_mutex_methods*);







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**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.459 2008/06/24 19:02:55 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

#ifdef SQLITE_ENABLE_FTS3
# include "fts3.h"
#endif
................................................................................
    }
    case SQLITE_CONFIG_SERIALIZED: {
      /* Enable all mutexing */
      sqlite3Config.bCoreMutex = 1;
      sqlite3Config.bFullMutex = 1;
      break;
    }
#ifdef SQLITE_ENABLE_MEMPOOL
    case SQLITE_CONFIG_MEMPOOL: {
      u8 *pMem = va_arg(ap, u8*);
      int nMem = va_arg(ap, int);
      rc = sqlite3MemSetMempool(pMem, nMem);
      break;
    }
#endif
    case SQLITE_CONFIG_MALLOC: {
      /* Specify an alternative malloc implementation */
      sqlite3Config.m = *va_arg(ap, sqlite3_mem_methods*);
      break;
    }
    case SQLITE_CONFIG_GETMALLOC: {
      /* Retrieve the current malloc() implementation */
      if( sqlite3Config.m.xMalloc==0 ) sqlite3MemSetDefault();
      *va_arg(ap, sqlite3_mem_methods*) = sqlite3Config.m;
      break;
    }
    case SQLITE_CONFIG_MUTEX: {
      /* Specify an alternative mutex implementation */
      sqlite3Config.mutex = *va_arg(ap, sqlite3_mutex_methods*);

Changes to src/mem3.c.

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**
*************************************************************************
** This file contains the C functions that implement a memory
** allocation subsystem for use by SQLite. 
**
** This version of the memory allocation subsystem omits all
** use of malloc().  All dynamically allocatable memory is
** contained in a static array, mem.aPool[].  The size of this
** fixed memory pool is SQLITE_MEMORY_SIZE bytes.
**
** This version of the memory allocation subsystem is used if
** and only if SQLITE_MEMORY_SIZE is defined.
**
** $Id: mem3.c,v 1.14 2008/06/18 17:09:10 danielk1977 Exp $
*/
#include "sqliteInt.h"

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



*/
#ifdef SQLITE_MEMORY_SIZE

/*
** Maximum size (in Mem3Blocks) of a "small" chunk.
*/
#define MX_SMALL 10


................................................................................
** is true if the previous chunk is checked out and false if the
** previous chunk is free.  The u.hdr.prevSize field is the size of
** the previous chunk in blocks if the previous chunk is on the
** freelist. If the previous chunk is checked out, then
** u.hdr.prevSize can be part of the data for that chunk and should
** not be read or written.
**
** We often identify a chunk by its index in mem.aPool[].  When
** this is done, the chunk index refers to the second block of
** the chunk.  In this way, the first chunk has an index of 1.
** A chunk index of 0 means "no such chunk" and is the equivalent
** of a NULL pointer.
**
** The second block of free chunks is of the form u.list.  The
** two fields form a double-linked list of chunks of related sizes.
** Pointers to the head of the list are stored in mem.aiSmall[] 
** for smaller chunks and mem.aiHash[] for larger chunks.
**
** The second block of a chunk is user data if the chunk is checked 
** out.  If a chunk is checked out, the user data may extend into
** the u.hdr.prevSize value of the following chunk.
*/
typedef struct Mem3Block Mem3Block;
struct Mem3Block {
  union {
    struct {
      u32 prevSize;   /* Size of previous chunk in Mem3Block elements */
      u32 size4x;     /* 4x the size of current chunk in Mem3Block elements */
    } hdr;
    struct {
      u32 next;       /* Index in mem.aPool[] of next free chunk */
      u32 prev;       /* Index in mem.aPool[] of previous free chunk */
    } list;
  } u;
};

/*
** All of the static variables used by this module are collected
** into a single structure named "mem".  This is to keep the
** static variables organized and to reduce namespace pollution
** when this module is combined with other in the amalgamation.
*/
static struct {
  /*
  ** True if we are evaluating an out-of-memory callback.
  */
................................................................................
  ** for smaller chunks, or a hash on the block size for larger
  ** chunks.
  */
  u32 aiSmall[MX_SMALL-1];   /* For sizes 2 through MX_SMALL, inclusive */
  u32 aiHash[N_HASH];        /* For sizes MX_SMALL+1 and larger */

  /*
  ** Memory available for allocation

  */


  Mem3Block aPool[SQLITE_MEMORY_SIZE/sizeof(Mem3Block)+2];
} mem;

/*
** Unlink the chunk at mem.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 = mem.aPool[i].u.list.next;
  u32 prev = mem.aPool[i].u.list.prev;
  assert( sqlite3_mutex_held(mem.mutex) );
  if( prev==0 ){
    *pRoot = next;
  }else{
    mem.aPool[prev].u.list.next = next;
  }
  if( next ){
    mem.aPool[next].u.list.prev = prev;
  }
  mem.aPool[i].u.list.next = 0;
  mem.aPool[i].u.list.prev = 0;
}

/*
** Unlink the chunk at index i from 
** whatever list is currently a member of.
*/
static void memsys3Unlink(u32 i){
  u32 size, hash;
  assert( sqlite3_mutex_held(mem.mutex) );
  assert( (mem.aPool[i-1].u.hdr.size4x & 1)==0 );
  assert( i>=1 );
  size = mem.aPool[i-1].u.hdr.size4x/4;
  assert( size==mem.aPool[i+size-1].u.hdr.prevSize );
  assert( size>=2 );
  if( size <= MX_SMALL ){
    memsys3UnlinkFromList(i, &mem.aiSmall[size-2]);
  }else{
    hash = size % N_HASH;
    memsys3UnlinkFromList(i, &mem.aiHash[hash]);
  }
}

/*
** Link the chunk at mem.aPool[i] so that is on the list rooted
** at *pRoot.
*/
static void memsys3LinkIntoList(u32 i, u32 *pRoot){
  assert( sqlite3_mutex_held(mem.mutex) );
  mem.aPool[i].u.list.next = *pRoot;
  mem.aPool[i].u.list.prev = 0;
  if( *pRoot ){
    mem.aPool[*pRoot].u.list.prev = i;
  }
  *pRoot = i;
}

/*
** Link the chunk at index i into either the appropriate
** small chunk list, or into the large chunk hash table.
*/
static void memsys3Link(u32 i){
  u32 size, hash;
  assert( sqlite3_mutex_held(mem.mutex) );
  assert( i>=1 );
  assert( (mem.aPool[i-1].u.hdr.size4x & 1)==0 );
  size = mem.aPool[i-1].u.hdr.size4x/4;
  assert( size==mem.aPool[i+size-1].u.hdr.prevSize );
  assert( size>=2 );
  if( size <= MX_SMALL ){
    memsys3LinkIntoList(i, &mem.aiSmall[size-2]);
  }else{
    hash = size % N_HASH;
    memsys3LinkIntoList(i, &mem.aiHash[hash]);
  }
}

/*
** Enter the mutex mem.mutex. Allocate it if it is not already allocated.
**
** Also:  Initialize the memory allocation subsystem the first time
** this routine is called.
*/
static void memsys3Enter(void){

  if( mem.mutex==0 ){
    mem.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);
    mem.aPool[0].u.hdr.size4x = SQLITE_MEMORY_SIZE/2 + 2;
    mem.aPool[SQLITE_MEMORY_SIZE/8].u.hdr.prevSize = SQLITE_MEMORY_SIZE/8;
    mem.aPool[SQLITE_MEMORY_SIZE/8].u.hdr.size4x = 1;
    mem.iMaster = 1;
    mem.szMaster = SQLITE_MEMORY_SIZE/8;
    mem.mnMaster = mem.szMaster;
  }
  sqlite3_mutex_enter(mem.mutex);

}


/*
** Return the amount of memory currently checked out.
*/
sqlite3_int64 sqlite3_memory_used(void){
  sqlite3_int64 n;
  memsys3Enter();
  n = SQLITE_MEMORY_SIZE - mem.szMaster*8;
  sqlite3_mutex_leave(mem.mutex);  
  return n;
}

/*
** Return the maximum amount of memory that has ever been
** checked out since either the beginning of this process
** or since the most recent reset.
*/
sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
  sqlite3_int64 n;
  memsys3Enter();
  n = SQLITE_MEMORY_SIZE - mem.mnMaster*8;
  if( resetFlag ){
    mem.mnMaster = mem.szMaster;
  }
  sqlite3_mutex_leave(mem.mutex);  
  return n;
}

/*
** Change the alarm callback.
**
** This is a no-op for the static memory allocator.  The purpose
** of the memory alarm is to support sqlite3_soft_heap_limit().
** But with this memory allocator, the soft_heap_limit is really
** a hard limit that is fixed at SQLITE_MEMORY_SIZE.
*/
int sqlite3_memory_alarm(
  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
  void *pArg,
  sqlite3_int64 iThreshold
){
  return SQLITE_OK;
}

/*
** Called when we are unable to satisfy an allocation of nBytes.
*/
static void memsys3OutOfMemory(int nByte){
  if( !mem.alarmBusy ){
    mem.alarmBusy = 1;
    assert( sqlite3_mutex_held(mem.mutex) );
    sqlite3_mutex_leave(mem.mutex);
    sqlite3_release_memory(nByte);
    sqlite3_mutex_enter(mem.mutex);
    mem.alarmBusy = 0;
  }
}

/*
** Return the size of an outstanding allocation, in bytes.  The
** size returned omits the 8-byte header overhead.  This only
** works for chunks that are currently checked out.
*/
int sqlite3MallocSize(void *p){
  int iSize = 0;
  if( p ){
    Mem3Block *pBlock = (Mem3Block*)p;
    assert( (pBlock[-1].u.hdr.size4x&1)!=0 );
    iSize = (pBlock[-1].u.hdr.size4x&~3)*2 - 4;
  }
  return iSize;
}

/*
** Initialize the memmory allocation subsystem.
*/
int sqlite3MallocInit(void){
  return SQLITE_OK;
}

/*
** Chunk i is a free chunk that has been unlinked.  Adjust its 
** size parameters for check-out and return a pointer to the 
** user portion of the chunk.
*/
static void *memsys3Checkout(u32 i, int nBlock){
  u32 x;
  assert( sqlite3_mutex_held(mem.mutex) );
  assert( i>=1 );
  assert( mem.aPool[i-1].u.hdr.size4x/4==nBlock );
  assert( mem.aPool[i+nBlock-1].u.hdr.prevSize==nBlock );
  x = mem.aPool[i-1].u.hdr.size4x;
  mem.aPool[i-1].u.hdr.size4x = nBlock*4 | 1 | (x&2);
  mem.aPool[i+nBlock-1].u.hdr.prevSize = nBlock;
  mem.aPool[i+nBlock-1].u.hdr.size4x |= 2;
  return &mem.aPool[i];
}

/*
** Carve a piece off of the end of the mem.iMaster free chunk.
** Return a pointer to the new allocation.  Or, if the master chunk
** is not large enough, return 0.
*/
static void *memsys3FromMaster(int nBlock){
  assert( sqlite3_mutex_held(mem.mutex) );
  assert( mem.szMaster>=nBlock );
  if( nBlock>=mem.szMaster-1 ){
    /* Use the entire master */
    void *p = memsys3Checkout(mem.iMaster, mem.szMaster);
    mem.iMaster = 0;
    mem.szMaster = 0;
    mem.mnMaster = 0;
    return p;
  }else{
    /* Split the master block.  Return the tail. */
    u32 newi, x;
    newi = mem.iMaster + mem.szMaster - nBlock;
    assert( newi > mem.iMaster+1 );
    mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.prevSize = nBlock;
    mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.size4x |= 2;
    mem.aPool[newi-1].u.hdr.size4x = nBlock*4 + 1;
    mem.szMaster -= nBlock;
    mem.aPool[newi-1].u.hdr.prevSize = mem.szMaster;
    x = mem.aPool[mem.iMaster-1].u.hdr.size4x & 2;
    mem.aPool[mem.iMaster-1].u.hdr.size4x = mem.szMaster*4 | x;
    if( mem.szMaster < mem.mnMaster ){
      mem.mnMaster = mem.szMaster;
    }
    return (void*)&mem.aPool[newi];
  }
}

/*
** *pRoot is the head of a list of free chunks of the same size
** or same size hash.  In other words, *pRoot is an entry in either
** mem.aiSmall[] or mem.aiHash[].  
**
** This routine examines all entries on the given list and tries
** to coalesce each entries with adjacent free chunks.  
**
** If it sees a chunk that is larger than mem.iMaster, it replaces 
** the current mem.iMaster with the new larger chunk.  In order for
** this mem.iMaster replacement to work, the master chunk must be
** linked into the hash tables.  That is not the normal state of
** affairs, of course.  The calling routine must link the master
** chunk before invoking this routine, then must unlink the (possibly
** changed) master chunk once this routine has finished.
*/
static void memsys3Merge(u32 *pRoot){
  u32 iNext, prev, size, i, x;

  assert( sqlite3_mutex_held(mem.mutex) );
  for(i=*pRoot; i>0; i=iNext){
    iNext = mem.aPool[i].u.list.next;
    size = mem.aPool[i-1].u.hdr.size4x;
    assert( (size&1)==0 );
    if( (size&2)==0 ){
      memsys3UnlinkFromList(i, pRoot);
      assert( i > mem.aPool[i-1].u.hdr.prevSize );
      prev = i - mem.aPool[i-1].u.hdr.prevSize;
      if( prev==iNext ){
        iNext = mem.aPool[prev].u.list.next;
      }
      memsys3Unlink(prev);
      size = i + size/4 - prev;
      x = mem.aPool[prev-1].u.hdr.size4x & 2;
      mem.aPool[prev-1].u.hdr.size4x = size*4 | x;
      mem.aPool[prev+size-1].u.hdr.prevSize = size;
      memsys3Link(prev);
      i = prev;
    }else{
      size /= 4;
    }
    if( size>mem.szMaster ){
      mem.iMaster = i;
      mem.szMaster = size;
    }
  }
}

/*
** Return a block of memory of at least nBytes in size.
** Return NULL if unable.
*/
static void *memsys3Malloc(int nByte){
  u32 i;
  int nBlock;
  int toFree;

  assert( sqlite3_mutex_held(mem.mutex) );
  assert( sizeof(Mem3Block)==8 );
  if( nByte<=12 ){
    nBlock = 2;
  }else{
    nBlock = (nByte + 11)/8;
  }
  assert( nBlock >= 2 );

  /* STEP 1:
  ** Look for an entry of the correct size in either the small
  ** chunk table or in the large chunk hash table.  This is
  ** successful most of the time (about 9 times out of 10).
  */
  if( nBlock <= MX_SMALL ){
    i = mem.aiSmall[nBlock-2];
    if( i>0 ){
      memsys3UnlinkFromList(i, &mem.aiSmall[nBlock-2]);
      return memsys3Checkout(i, nBlock);
    }
  }else{
    int hash = nBlock % N_HASH;
    for(i=mem.aiHash[hash]; i>0; i=mem.aPool[i].u.list.next){
      if( mem.aPool[i-1].u.hdr.size4x/4==nBlock ){
        memsys3UnlinkFromList(i, &mem.aiHash[hash]);
        return memsys3Checkout(i, nBlock);
      }
    }
  }

  /* STEP 2:
  ** Try to satisfy the allocation by carving a piece off of the end
  ** of the master chunk.  This step usually works if step 1 fails.
  */
  if( mem.szMaster>=nBlock ){
    return memsys3FromMaster(nBlock);
  }


  /* STEP 3:  
  ** Loop through the entire memory pool.  Coalesce adjacent free
  ** chunks.  Recompute the master chunk as the largest free chunk.
  ** Then try again to satisfy the allocation by carving a piece off
  ** of the end of the master chunk.  This step happens very
  ** rarely (we hope!)
  */
  for(toFree=nBlock*16; toFree<SQLITE_MEMORY_SIZE*2; toFree *= 2){
    memsys3OutOfMemory(toFree);
    if( mem.iMaster ){
      memsys3Link(mem.iMaster);
      mem.iMaster = 0;
      mem.szMaster = 0;
    }
    for(i=0; i<N_HASH; i++){
      memsys3Merge(&mem.aiHash[i]);
    }
    for(i=0; i<MX_SMALL-1; i++){
      memsys3Merge(&mem.aiSmall[i]);
    }
    if( mem.szMaster ){
      memsys3Unlink(mem.iMaster);
      if( mem.szMaster>=nBlock ){
        return memsys3FromMaster(nBlock);
      }
    }
  }

  /* If none of the above worked, then we fail. */
  return 0;
................................................................................
/*
** Free an outstanding memory allocation.
*/
void memsys3Free(void *pOld){
  Mem3Block *p = (Mem3Block*)pOld;
  int i;
  u32 size, x;
  assert( sqlite3_mutex_held(mem.mutex) );
  assert( p>mem.aPool && p<&mem.aPool[SQLITE_MEMORY_SIZE/8] );
  i = p - mem.aPool;
  assert( (mem.aPool[i-1].u.hdr.size4x&1)==1 );
  size = mem.aPool[i-1].u.hdr.size4x/4;
  assert( i+size<=SQLITE_MEMORY_SIZE/8+1 );
  mem.aPool[i-1].u.hdr.size4x &= ~1;
  mem.aPool[i+size-1].u.hdr.prevSize = size;
  mem.aPool[i+size-1].u.hdr.size4x &= ~2;
  memsys3Link(i);

  /* Try to expand the master using the newly freed chunk */
  if( mem.iMaster ){
    while( (mem.aPool[mem.iMaster-1].u.hdr.size4x&2)==0 ){
      size = mem.aPool[mem.iMaster-1].u.hdr.prevSize;
      mem.iMaster -= size;
      mem.szMaster += size;
      memsys3Unlink(mem.iMaster);
      x = mem.aPool[mem.iMaster-1].u.hdr.size4x & 2;
      mem.aPool[mem.iMaster-1].u.hdr.size4x = mem.szMaster*4 | x;
      mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.prevSize = mem.szMaster;
    }
    x = mem.aPool[mem.iMaster-1].u.hdr.size4x & 2;
    while( (mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.size4x&1)==0 ){
      memsys3Unlink(mem.iMaster+mem.szMaster);
      mem.szMaster += mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.size4x/4;
      mem.aPool[mem.iMaster-1].u.hdr.size4x = mem.szMaster*4 | x;
      mem.aPool[mem.iMaster+mem.szMaster-1].u.hdr.prevSize = mem.szMaster;
    }
  }
}

/*
** Allocate nBytes of memory
*/
void *sqlite3_malloc(int nBytes){
  sqlite3_int64 *p = 0;
  if( nBytes>0 ){
    memsys3Enter();
    p = memsys3Malloc(nBytes);
    sqlite3_mutex_leave(mem.mutex);
  }
  return (void*)p; 
}

/*
** Free memory.
*/
void sqlite3_free(void *pPrior){
  if( pPrior==0 ){
    return;


  }








  assert( mem.mutex!=0 );
  sqlite3_mutex_enter(mem.mutex);
  memsys3Free(pPrior);
  sqlite3_mutex_leave(mem.mutex);  


}

/*
** Change the size of an existing memory allocation
*/
void *sqlite3_realloc(void *pPrior, int nBytes){
  int nOld;
  void *p;
  if( pPrior==0 ){
    return sqlite3_malloc(nBytes);
  }
  if( nBytes<=0 ){
    sqlite3_free(pPrior);
    return 0;
  }
  assert( mem.mutex!=0 );
  nOld = sqlite3MallocSize(pPrior);
  if( nBytes<=nOld && nBytes>=nOld-128 ){
    return pPrior;
  }
  sqlite3_mutex_enter(mem.mutex);
  p = memsys3Malloc(nBytes);
  if( p ){
    if( nOld<nBytes ){
      memcpy(p, pPrior, nOld);
    }else{
      memcpy(p, pPrior, nBytes);
    }
    memsys3Free(pPrior);
  }
  sqlite3_mutex_leave(mem.mutex);
  return p;
}

























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

void sqlite3MemdebugDump(const char *zFilename){
#ifdef SQLITE_DEBUG
  FILE *out;
  int i, j;
  u32 size;
  if( zFilename==0 || zFilename[0]==0 ){
    out = stdout;
................................................................................
                      zFilename);
      return;
    }
  }
  memsys3Enter();
  fprintf(out, "CHUNKS:\n");
  for(i=1; i<=SQLITE_MEMORY_SIZE/8; i+=size/4){
    size = mem.aPool[i-1].u.hdr.size4x;
    if( size/4<=1 ){
      fprintf(out, "%p size error\n", &mem.aPool[i]);
      assert( 0 );
      break;
    }
    if( (size&1)==0 && mem.aPool[i+size/4-1].u.hdr.prevSize!=size/4 ){
      fprintf(out, "%p tail size does not match\n", &mem.aPool[i]);
      assert( 0 );
      break;
    }
    if( ((mem.aPool[i+size/4-1].u.hdr.size4x&2)>>1)!=(size&1) ){
      fprintf(out, "%p tail checkout bit is incorrect\n", &mem.aPool[i]);
      assert( 0 );
      break;
    }
    if( size&1 ){
      fprintf(out, "%p %6d bytes checked out\n", &mem.aPool[i], (size/4)*8-8);
    }else{
      fprintf(out, "%p %6d bytes free%s\n", &mem.aPool[i], (size/4)*8-8,
                  i==mem.iMaster ? " **master**" : "");
    }
  }
  for(i=0; i<MX_SMALL-1; i++){
    if( mem.aiSmall[i]==0 ) continue;
    fprintf(out, "small(%2d):", i);
    for(j = mem.aiSmall[i]; j>0; j=mem.aPool[j].u.list.next){
      fprintf(out, " %p(%d)", &mem.aPool[j],
              (mem.aPool[j-1].u.hdr.size4x/4)*8-8);
    }
    fprintf(out, "\n"); 
  }
  for(i=0; i<N_HASH; i++){
    if( mem.aiHash[i]==0 ) continue;
    fprintf(out, "hash(%2d):", i);
    for(j = mem.aiHash[i]; j>0; j=mem.aPool[j].u.list.next){
      fprintf(out, " %p(%d)", &mem.aPool[j],
              (mem.aPool[j-1].u.hdr.size4x/4)*8-8);
    }
    fprintf(out, "\n"); 
  }
  fprintf(out, "master=%d\n", mem.iMaster);
  fprintf(out, "nowUsed=%d\n", SQLITE_MEMORY_SIZE - mem.szMaster*8);
  fprintf(out, "mxUsed=%d\n", SQLITE_MEMORY_SIZE - mem.mnMaster*8);
  sqlite3_mutex_leave(mem.mutex);
  if( out==stdout ){
    fflush(stdout);
  }else{
    fclose(out);
  }
#endif
}























#endif /* !SQLITE_MEMORY_SIZE */



























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**
*************************************************************************
** This file contains the C functions that implement a memory
** allocation subsystem for use by SQLite. 
**
** This version of the memory allocation subsystem omits all
** use of malloc().  All dynamically allocatable memory is
** contained in a static array, mem3.aPool[].  The size of this
** fixed memory pool is SQLITE_MEMORY_SIZE bytes.
**
** This version of the memory allocation subsystem is used if
** and only if SQLITE_MEMORY_SIZE is defined.
**
** $Id: mem3.c,v 1.15 2008/06/24 19:02:55 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** This version of the memory allocator is only built into the library
** SQLITE_ENABLE_MEMPOOL is defined. Defining this symbol does not
** mean that the library will use a memory-pool by default, just that
** it is available. The mempool allocator is activated by calling
** sqlite3_config().
*/
#ifdef SQLITE_ENABLE_MEMPOOL

/*
** Maximum size (in Mem3Blocks) of a "small" chunk.
*/
#define MX_SMALL 10


................................................................................
** is true if the previous chunk is checked out and false if the
** previous chunk is free.  The u.hdr.prevSize field is the size of
** the previous chunk in blocks if the previous chunk is on the
** freelist. If the previous chunk is checked out, then
** u.hdr.prevSize can be part of the data for that chunk and should
** not be read or written.
**
** We often identify a chunk by its index in mem3.aPool[].  When
** this is done, the chunk index refers to the second block of
** the chunk.  In this way, the first chunk has an index of 1.
** A chunk index of 0 means "no such chunk" and is the equivalent
** of a NULL pointer.
**
** The second block of free chunks is of the form u.list.  The
** two fields form a double-linked list of chunks of related sizes.
** Pointers to the head of the list are stored in mem3.aiSmall[] 
** for smaller chunks and mem3.aiHash[] for larger chunks.
**
** The second block of a chunk is user data if the chunk is checked 
** out.  If a chunk is checked out, the user data may extend into
** the u.hdr.prevSize value of the following chunk.
*/
typedef struct Mem3Block Mem3Block;
struct Mem3Block {
  union {
    struct {
      u32 prevSize;   /* Size of previous chunk in Mem3Block elements */
      u32 size4x;     /* 4x the size of current chunk in Mem3Block elements */
    } hdr;
    struct {
      u32 next;       /* Index in mem3.aPool[] of next free chunk */
      u32 prev;       /* Index in mem3.aPool[] of previous free chunk */
    } list;
  } u;
};

/*
** 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 struct {
  /*
  ** True if we are evaluating an out-of-memory callback.
  */
................................................................................
  ** for smaller chunks, or a hash on the block size for larger
  ** chunks.
  */
  u32 aiSmall[MX_SMALL-1];   /* For sizes 2 through MX_SMALL, inclusive */
  u32 aiHash[N_HASH];        /* For sizes MX_SMALL+1 and larger */

  /*
  ** Memory available for allocation. nPool is the size of the array
  ** (in Mem3Blocks) pointed to by aPool less 2.
  */
  u32 nPool;
  Mem3Block *aPool;
  /* Mem3Block aPool[SQLITE_MEMORY_SIZE/sizeof(Mem3Block)+2]; */
} 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;
  u32 prev = mem3.aPool[i].u.list.prev;
  assert( sqlite3_mutex_held(mem3.mutex) );
  if( prev==0 ){
    *pRoot = next;
  }else{
    mem3.aPool[prev].u.list.next = next;
  }
  if( next ){
    mem3.aPool[next].u.list.prev = prev;
  }
  mem3.aPool[i].u.list.next = 0;
  mem3.aPool[i].u.list.prev = 0;
}

/*
** Unlink the chunk at index i from 
** whatever list is currently a member of.
*/
static void memsys3Unlink(u32 i){
  u32 size, hash;
  assert( sqlite3_mutex_held(mem3.mutex) );
  assert( (mem3.aPool[i-1].u.hdr.size4x & 1)==0 );
  assert( i>=1 );
  size = mem3.aPool[i-1].u.hdr.size4x/4;
  assert( size==mem3.aPool[i+size-1].u.hdr.prevSize );
  assert( size>=2 );
  if( size <= MX_SMALL ){
    memsys3UnlinkFromList(i, &mem3.aiSmall[size-2]);
  }else{
    hash = size % N_HASH;
    memsys3UnlinkFromList(i, &mem3.aiHash[hash]);
  }
}

/*
** Link the chunk at mem3.aPool[i] so that is on the list rooted
** at *pRoot.
*/
static void memsys3LinkIntoList(u32 i, u32 *pRoot){
  assert( sqlite3_mutex_held(mem3.mutex) );
  mem3.aPool[i].u.list.next = *pRoot;
  mem3.aPool[i].u.list.prev = 0;
  if( *pRoot ){
    mem3.aPool[*pRoot].u.list.prev = i;
  }
  *pRoot = i;
}

/*
** Link the chunk at index i into either the appropriate
** small chunk list, or into the large chunk hash table.
*/
static void memsys3Link(u32 i){
  u32 size, hash;
  assert( sqlite3_mutex_held(mem3.mutex) );
  assert( i>=1 );
  assert( (mem3.aPool[i-1].u.hdr.size4x & 1)==0 );
  size = mem3.aPool[i-1].u.hdr.size4x/4;
  assert( size==mem3.aPool[i+size-1].u.hdr.prevSize );
  assert( size>=2 );
  if( size <= MX_SMALL ){
    memsys3LinkIntoList(i, &mem3.aiSmall[size-2]);
  }else{
    hash = size % N_HASH;
    memsys3LinkIntoList(i, &mem3.aiHash[hash]);
  }
}

/*
** Enter the mutex mem3.mutex. Allocate it if it is not already allocated.
**
** Also:  Initialize the memory allocation subsystem the first time
** this routine is called.
*/
static void memsys3Enter(void){
#if 0
  if( mem3.mutex==0 ){
    mem3.mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MEM);






  }
  sqlite3_mutex_enter(mem3.mutex);
#endif
}
static void memsys3Leave(void){
}











/*
































** Called when we are unable to satisfy an allocation of nBytes.
*/
static void memsys3OutOfMemory(int nByte){
  if( !mem3.alarmBusy ){
    mem3.alarmBusy = 1;
    assert( sqlite3_mutex_held(mem3.mutex) );
    sqlite3_mutex_leave(mem3.mutex);
    sqlite3_release_memory(nByte);
    sqlite3_mutex_enter(mem3.mutex);
    mem3.alarmBusy = 0;
  }
}























/*
** Chunk i is a free chunk that has been unlinked.  Adjust its 
** size parameters for check-out and return a pointer to the 
** user portion of the chunk.
*/
static void *memsys3Checkout(u32 i, int nBlock){
  u32 x;
  assert( sqlite3_mutex_held(mem3.mutex) );
  assert( i>=1 );
  assert( mem3.aPool[i-1].u.hdr.size4x/4==nBlock );
  assert( mem3.aPool[i+nBlock-1].u.hdr.prevSize==nBlock );
  x = mem3.aPool[i-1].u.hdr.size4x;
  mem3.aPool[i-1].u.hdr.size4x = nBlock*4 | 1 | (x&2);
  mem3.aPool[i+nBlock-1].u.hdr.prevSize = nBlock;
  mem3.aPool[i+nBlock-1].u.hdr.size4x |= 2;
  return &mem3.aPool[i];
}

/*
** Carve a piece off of the end of the mem3.iMaster free chunk.
** Return a pointer to the new allocation.  Or, if the master chunk
** is not large enough, return 0.
*/
static void *memsys3FromMaster(int nBlock){
  assert( sqlite3_mutex_held(mem3.mutex) );
  assert( mem3.szMaster>=nBlock );
  if( nBlock>=mem3.szMaster-1 ){
    /* Use the entire master */
    void *p = memsys3Checkout(mem3.iMaster, mem3.szMaster);
    mem3.iMaster = 0;
    mem3.szMaster = 0;
    mem3.mnMaster = 0;
    return p;
  }else{
    /* Split the master block.  Return the tail. */
    u32 newi, x;
    newi = mem3.iMaster + mem3.szMaster - nBlock;
    assert( newi > mem3.iMaster+1 );
    mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = nBlock;
    mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x |= 2;
    mem3.aPool[newi-1].u.hdr.size4x = nBlock*4 + 1;
    mem3.szMaster -= nBlock;
    mem3.aPool[newi-1].u.hdr.prevSize = mem3.szMaster;
    x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
    mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
    if( mem3.szMaster < mem3.mnMaster ){
      mem3.mnMaster = mem3.szMaster;
    }
    return (void*)&mem3.aPool[newi];
  }
}

/*
** *pRoot is the head of a list of free chunks of the same size
** or same size hash.  In other words, *pRoot is an entry in either
** mem3.aiSmall[] or mem3.aiHash[].  
**
** This routine examines all entries on the given list and tries
** to coalesce each entries with adjacent free chunks.  
**
** If it sees a chunk that is larger than mem3.iMaster, it replaces 
** the current mem3.iMaster with the new larger chunk.  In order for
** this mem3.iMaster replacement to work, the master chunk must be
** linked into the hash tables.  That is not the normal state of
** affairs, of course.  The calling routine must link the master
** chunk before invoking this routine, then must unlink the (possibly
** changed) master chunk once this routine has finished.
*/
static void memsys3Merge(u32 *pRoot){
  u32 iNext, prev, size, i, x;

  assert( sqlite3_mutex_held(mem3.mutex) );
  for(i=*pRoot; i>0; i=iNext){
    iNext = mem3.aPool[i].u.list.next;
    size = mem3.aPool[i-1].u.hdr.size4x;
    assert( (size&1)==0 );
    if( (size&2)==0 ){
      memsys3UnlinkFromList(i, pRoot);
      assert( i > mem3.aPool[i-1].u.hdr.prevSize );
      prev = i - mem3.aPool[i-1].u.hdr.prevSize;
      if( prev==iNext ){
        iNext = mem3.aPool[prev].u.list.next;
      }
      memsys3Unlink(prev);
      size = i + size/4 - prev;
      x = mem3.aPool[prev-1].u.hdr.size4x & 2;
      mem3.aPool[prev-1].u.hdr.size4x = size*4 | x;
      mem3.aPool[prev+size-1].u.hdr.prevSize = size;
      memsys3Link(prev);
      i = prev;
    }else{
      size /= 4;
    }
    if( size>mem3.szMaster ){
      mem3.iMaster = i;
      mem3.szMaster = size;
    }
  }
}

/*
** Return a block of memory of at least nBytes in size.
** Return NULL if unable.
*/
static void *memsys3Malloc(int nByte){
  u32 i;
  int nBlock;
  int toFree;

  assert( sqlite3_mutex_held(mem3.mutex) );
  assert( sizeof(Mem3Block)==8 );
  if( nByte<=12 ){
    nBlock = 2;
  }else{
    nBlock = (nByte + 11)/8;
  }
  assert( nBlock>=2 );

  /* STEP 1:
  ** Look for an entry of the correct size in either the small
  ** chunk table or in the large chunk hash table.  This is
  ** successful most of the time (about 9 times out of 10).
  */
  if( nBlock <= MX_SMALL ){
    i = mem3.aiSmall[nBlock-2];
    if( i>0 ){
      memsys3UnlinkFromList(i, &mem3.aiSmall[nBlock-2]);
      return memsys3Checkout(i, nBlock);
    }
  }else{
    int hash = nBlock % N_HASH;
    for(i=mem3.aiHash[hash]; i>0; i=mem3.aPool[i].u.list.next){
      if( mem3.aPool[i-1].u.hdr.size4x/4==nBlock ){
        memsys3UnlinkFromList(i, &mem3.aiHash[hash]);
        return memsys3Checkout(i, nBlock);
      }
    }
  }

  /* STEP 2:
  ** Try to satisfy the allocation by carving a piece off of the end
  ** of the master chunk.  This step usually works if step 1 fails.
  */
  if( mem3.szMaster>=nBlock ){
    return memsys3FromMaster(nBlock);
  }


  /* STEP 3:  
  ** Loop through the entire memory pool.  Coalesce adjacent free
  ** chunks.  Recompute the master chunk as the largest free chunk.
  ** Then try again to satisfy the allocation by carving a piece off
  ** of the end of the master chunk.  This step happens very
  ** rarely (we hope!)
  */
  for(toFree=nBlock*16; toFree<(mem3.nPool*16); toFree *= 2){
    memsys3OutOfMemory(toFree);
    if( mem3.iMaster ){
      memsys3Link(mem3.iMaster);
      mem3.iMaster = 0;
      mem3.szMaster = 0;
    }
    for(i=0; i<N_HASH; i++){
      memsys3Merge(&mem3.aiHash[i]);
    }
    for(i=0; i<MX_SMALL-1; i++){
      memsys3Merge(&mem3.aiSmall[i]);
    }
    if( mem3.szMaster ){
      memsys3Unlink(mem3.iMaster);
      if( mem3.szMaster>=nBlock ){
        return memsys3FromMaster(nBlock);
      }
    }
  }

  /* If none of the above worked, then we fail. */
  return 0;
................................................................................
/*
** Free an outstanding memory allocation.
*/
void memsys3Free(void *pOld){
  Mem3Block *p = (Mem3Block*)pOld;
  int i;
  u32 size, x;
  assert( sqlite3_mutex_held(mem3.mutex) );
  assert( p>mem3.aPool && p<&mem3.aPool[mem3.nPool] );
  i = p - mem3.aPool;
  assert( (mem3.aPool[i-1].u.hdr.size4x&1)==1 );
  size = mem3.aPool[i-1].u.hdr.size4x/4;
  assert( i+size<=mem3.nPool+1 );
  mem3.aPool[i-1].u.hdr.size4x &= ~1;
  mem3.aPool[i+size-1].u.hdr.prevSize = size;
  mem3.aPool[i+size-1].u.hdr.size4x &= ~2;
  memsys3Link(i);

  /* Try to expand the master using the newly freed chunk */
  if( mem3.iMaster ){
    while( (mem3.aPool[mem3.iMaster-1].u.hdr.size4x&2)==0 ){
      size = mem3.aPool[mem3.iMaster-1].u.hdr.prevSize;
      mem3.iMaster -= size;
      mem3.szMaster += size;
      memsys3Unlink(mem3.iMaster);
      x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
      mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
      mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = mem3.szMaster;
    }
    x = mem3.aPool[mem3.iMaster-1].u.hdr.size4x & 2;
    while( (mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x&1)==0 ){
      memsys3Unlink(mem3.iMaster+mem3.szMaster);
      mem3.szMaster += mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.size4x/4;
      mem3.aPool[mem3.iMaster-1].u.hdr.size4x = mem3.szMaster*4 | x;
      mem3.aPool[mem3.iMaster+mem3.szMaster-1].u.hdr.prevSize = mem3.szMaster;
    }
  }
}

/*
** Allocate nBytes of memory.
*/
static void *mempoolMalloc(int nBytes){
  sqlite3_int64 *p;
  assert( nBytes>0 );          /* malloc.c filters out 0 byte requests */
  memsys3Enter();
  p = memsys3Malloc(nBytes);
  memsys3Leave();

  return (void*)p; 
}

/*
** Free memory.
*/
void mempoolFree(void *pPrior){
  assert( pPrior );
  memsys3Enter();
  memsys3Free(pPrior);
  memsys3Leave();
}

/*
** Return the size of an outstanding allocation, in bytes.  The
** size returned omits the 8-byte header overhead.  This only
** works for chunks that are currently checked out.
*/
static int mempoolSize(void *p){
  Mem3Block *pBlock = (Mem3Block*)p;
  assert( pBlock );



  assert( (pBlock[-1].u.hdr.size4x&1)!=0 );
  return (pBlock[-1].u.hdr.size4x&~3)*2 - 4;
}

/*
** Change the size of an existing memory allocation
*/
void *mempoolRealloc(void *pPrior, int nBytes){
  int nOld;
  void *p;
  if( pPrior==0 ){
    return sqlite3_malloc(nBytes);
  }
  if( nBytes<=0 ){
    sqlite3_free(pPrior);
    return 0;
  }

  nOld = mempoolSize(pPrior);
  if( nBytes<=nOld && nBytes>=nOld-128 ){
    return pPrior;
  }
  memsys3Enter();
  p = mempoolMalloc(nBytes);
  if( p ){
    if( nOld<nBytes ){
      memcpy(p, pPrior, nOld);
    }else{
      memcpy(p, pPrior, nBytes);
    }
    mempoolFree(pPrior);
  }
  memsys3Leave();
  return p;
}

/*
** Round up a request size to the next valid allocation size.
*/
static int mempoolRoundup(int n){
  /* TODO: Fix me */
  return n;
}

/*
** Initialize this module.
*/
static int mempoolInit(void *NotUsed){
  return SQLITE_OK;
}

/*
** Deinitialize this module.
*/
static void mempoolShutdown(void *NotUsed){
  return;
}



/*
** Open the file indicated and write a log of all unfreed memory 
** allocations into that log.
*/
#if 0
void sqlite3MemdebugDump(const char *zFilename){
#ifdef SQLITE_DEBUG
  FILE *out;
  int i, j;
  u32 size;
  if( zFilename==0 || zFilename[0]==0 ){
    out = stdout;
................................................................................
                      zFilename);
      return;
    }
  }
  memsys3Enter();
  fprintf(out, "CHUNKS:\n");
  for(i=1; i<=SQLITE_MEMORY_SIZE/8; i+=size/4){
    size = mem3.aPool[i-1].u.hdr.size4x;
    if( size/4<=1 ){
      fprintf(out, "%p size error\n", &mem3.aPool[i]);
      assert( 0 );
      break;
    }
    if( (size&1)==0 && mem3.aPool[i+size/4-1].u.hdr.prevSize!=size/4 ){
      fprintf(out, "%p tail size does not match\n", &mem3.aPool[i]);
      assert( 0 );
      break;
    }
    if( ((mem3.aPool[i+size/4-1].u.hdr.size4x&2)>>1)!=(size&1) ){
      fprintf(out, "%p tail checkout bit is incorrect\n", &mem3.aPool[i]);
      assert( 0 );
      break;
    }
    if( size&1 ){
      fprintf(out, "%p %6d bytes checked out\n", &mem3.aPool[i], (size/4)*8-8);
    }else{
      fprintf(out, "%p %6d bytes free%s\n", &mem3.aPool[i], (size/4)*8-8,
                  i==mem3.iMaster ? " **master**" : "");
    }
  }
  for(i=0; i<MX_SMALL-1; i++){
    if( mem3.aiSmall[i]==0 ) continue;
    fprintf(out, "small(%2d):", i);
    for(j = mem3.aiSmall[i]; j>0; j=mem3.aPool[j].u.list.next){
      fprintf(out, " %p(%d)", &mem3.aPool[j],
              (mem3.aPool[j-1].u.hdr.size4x/4)*8-8);
    }
    fprintf(out, "\n"); 
  }
  for(i=0; i<N_HASH; i++){
    if( mem3.aiHash[i]==0 ) continue;
    fprintf(out, "hash(%2d):", i);
    for(j = mem3.aiHash[i]; j>0; j=mem3.aPool[j].u.list.next){
      fprintf(out, " %p(%d)", &mem3.aPool[j],
              (mem3.aPool[j-1].u.hdr.size4x/4)*8-8);
    }
    fprintf(out, "\n"); 
  }
  fprintf(out, "master=%d\n", mem3.iMaster);
  fprintf(out, "nowUsed=%d\n", SQLITE_MEMORY_SIZE - mem3.szMaster*8);
  fprintf(out, "mxUsed=%d\n", SQLITE_MEMORY_SIZE - mem3.mnMaster*8);
  sqlite3_mutex_leave(mem3.mutex);
  if( out==stdout ){
    fflush(stdout);
  }else{
    fclose(out);
  }
#endif
}
#endif

/*
** This routine is the only routine in this file with external 
** linkage.
**
** Populate the low-level memory allocation function pointers in
** sqlite3Config.m with pointers to the routines in this file. The
** arguments specify the block of memory to manage.
**
** This routine is only called by sqlite3_config(), and therefore
** is not required to be threadsafe (it is not).
*/
void sqlite3MemSetMempool(u8 *pBlock, int nBlock){
  static const sqlite3_mem_methods mempoolMethods = {
     mempoolMalloc,
     mempoolFree,
     mempoolRealloc,
     mempoolSize,
     mempoolRoundup,
     mempoolInit,
     mempoolShutdown,
     0

  };

  /* Configure the functions to call to allocate memory. */
  sqlite3_config(SQLITE_CONFIG_MALLOC, &mempoolMethods);

  /* Store a pointer to the memory block in global structure mem3. */
  assert( sizeof(Mem3Block)==8 );
  mem3.aPool = (Mem3Block *)pBlock;
  mem3.nPool = (nBlock / sizeof(Mem3Block)) - 2;

  /* Initialize the master block. */
  mem3.szMaster = mem3.nPool;
  mem3.mnMaster = mem3.szMaster;
  mem3.iMaster = 1;
  mem3.aPool[0].u.hdr.size4x = (mem3.szMaster<<2) + 2;
  mem3.aPool[mem3.nPool].u.hdr.prevSize = mem3.nPool;
  mem3.aPool[mem3.nPool].u.hdr.size4x = 1;
}

#endif /* SQLITE_MEMPOOL_MALLOC */

Changes to src/sqlite.h.in.

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1111
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** 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 1.354 2008/06/24 09:52:39 danielk1977 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++.
................................................................................
#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
#define SQLITE_CONFIG_SCRATCH       6  /* void*, int sz, int N */
#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */


/*
** CAPI3REF: Enable Or Disable Extended Result Codes {F12200}
**
** The sqlite3_extended_result_codes() routine enables or disables the
** [extended result codes] feature of SQLite. The extended result
** codes are disabled by default for historical compatibility considerations.







|







 







>







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29
30
31
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33
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....
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
** 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 1.355 2008/06/24 19:02:55 danielk1977 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++.
................................................................................
#define SQLITE_CONFIG_GETMALLOC     5  /* sqlite3_mem_methods* */
#define SQLITE_CONFIG_SCRATCH       6  /* void*, int sz, int N */
#define SQLITE_CONFIG_PAGECACHE     7  /* void*, int sz, int N */
#define SQLITE_CONFIG_HEAP          8  /* void*, int nByte, int min */
#define SQLITE_CONFIG_MEMSTATUS     9  /* boolean */
#define SQLITE_CONFIG_MUTEX        10  /* sqlite3_mutex_methods* */
#define SQLITE_CONFIG_GETMUTEX     11  /* sqlite3_mutex_methods* */
#define SQLITE_CONFIG_MEMPOOL      12  /* u8*, int */

/*
** CAPI3REF: Enable Or Disable Extended Result Codes {F12200}
**
** The sqlite3_extended_result_codes() routine enables or disables the
** [extended result codes] feature of SQLite. The extended result
** codes are disabled by default for historical compatibility considerations.

Changes to src/test_malloc.c.

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10
11
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926
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1027
1028
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1031

1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code used to implement test interfaces to the
** memory allocation subsystem.
**
** $Id: test_malloc.c,v 1.28 2008/06/20 14:59:51 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>

................................................................................
  }
  pResult = Tcl_NewObj();
  Tcl_ListObjAppendElement(0, pResult, Tcl_NewIntObj(rc));
  Tcl_ListObjAppendElement(0, pResult, Tcl_NewIntObj(N));
  Tcl_SetObjResult(interp, pResult);
  return TCL_OK;
}

































/*
** Usage:    sqlite3_status  OPCODE  RESETFLAG
**
** Return a list of three elements which are the sqlite3_status() return
** code, the current value, and the high-water mark value.
*/
................................................................................
     { "sqlite3_memdebug_fail",      test_memdebug_fail            },
     { "sqlite3_memdebug_pending",   test_memdebug_pending         },
     { "sqlite3_memdebug_settitle",  test_memdebug_settitle        },
     { "sqlite3_memdebug_malloc_count", test_memdebug_malloc_count },
     { "sqlite3_memdebug_log",       test_memdebug_log             },
     { "sqlite3_config_scratch",     test_config_scratch           },
     { "sqlite3_config_pagecache",   test_config_pagecache         },

     { "sqlite3_status",             test_status                   },
     { "install_malloc_faultsim",    test_install_malloc_faultsim  },
  };
  int i;
  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, aObjCmd[i].xProc, 0, 0);
  }
  return TCL_OK;
}
#endif







|







 







>
>
>
>
>
>
>
>
>
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>
>
>
>
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>







 







>










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...
925
926
927
928
929
930
931
932
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941
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1060
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1062
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1064
1065
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**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code used to implement test interfaces to the
** memory allocation subsystem.
**
** $Id: test_malloc.c,v 1.29 2008/06/24 19:02:55 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>

................................................................................
  }
  pResult = Tcl_NewObj();
  Tcl_ListObjAppendElement(0, pResult, Tcl_NewIntObj(rc));
  Tcl_ListObjAppendElement(0, pResult, Tcl_NewIntObj(N));
  Tcl_SetObjResult(interp, pResult);
  return TCL_OK;
}

/*
** Usage:    sqlite3_config_mempool NBYTE
**
*/
static int test_config_mempool(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  int sz, rc;
  Tcl_Obj *pResult;
  static char buf[1000000];
  if( objc!=2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "NBYTE");
    return TCL_ERROR;
  }
  if( Tcl_GetIntFromObj(interp, objv[1], &sz) ) return TCL_ERROR;
  if( sz<=0 ){
    sqlite3_mem_methods m;
    memset(&m, 0, sizeof(sqlite3_mem_methods));
    rc = sqlite3_config(SQLITE_CONFIG_MALLOC, &m);
  }else{
    if( sz>sizeof(buf) ){
      sz = sizeof(buf);
    }
    rc = sqlite3_config(SQLITE_CONFIG_MEMPOOL, buf, sz);
  }
  Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_VOLATILE);
  return TCL_OK;
}

/*
** Usage:    sqlite3_status  OPCODE  RESETFLAG
**
** Return a list of three elements which are the sqlite3_status() return
** code, the current value, and the high-water mark value.
*/
................................................................................
     { "sqlite3_memdebug_fail",      test_memdebug_fail            },
     { "sqlite3_memdebug_pending",   test_memdebug_pending         },
     { "sqlite3_memdebug_settitle",  test_memdebug_settitle        },
     { "sqlite3_memdebug_malloc_count", test_memdebug_malloc_count },
     { "sqlite3_memdebug_log",       test_memdebug_log             },
     { "sqlite3_config_scratch",     test_config_scratch           },
     { "sqlite3_config_pagecache",   test_config_pagecache         },
     { "sqlite3_config_mempool",     test_config_mempool           },
     { "sqlite3_status",             test_status                   },
     { "install_malloc_faultsim",    test_install_malloc_faultsim  },
  };
  int i;
  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, aObjCmd[i].xProc, 0, 0);
  }
  return TCL_OK;
}
#endif

Changes to test/permutations.test.

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#
#    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: permutations.test,v 1.3 2008/06/23 15:55:52 danielk1977 Exp $

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

# Argument processing.
#
set ::testmode [lindex $argv 0]
................................................................................
# Run some ioerr-tests in autovacuum mode.
#
run_tests "autovacuum_ioerr" -description {
  Run ioerr.test in autovacuum mode.
} -presql {
  pragma auto_vacuum = 1
} -include ioerr.test


















# run_tests "crash_safe_append" -description {
#   Run crash.test with persistent journals on a SAFE_APPEND file-system.
# } -initialize {
#   rename crashsql sa_crashsql
#   proc crashsql {args} {
#     set options [lrange $args 0 [expr {[llength $args]-2}]]







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#
#    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: permutations.test,v 1.4 2008/06/24 19:02:55 danielk1977 Exp $

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

# Argument processing.
#
set ::testmode [lindex $argv 0]
................................................................................
# Run some ioerr-tests in autovacuum mode.
#
run_tests "autovacuum_ioerr" -description {
  Run ioerr.test in autovacuum mode.
} -presql {
  pragma auto_vacuum = 1
} -include ioerr.test

run_tests "mempool" -description {
  Run tests using the allocator in mem3.c.
} -initialize {
  catch {db close}
  sqlite3_reset_auto_extension
  sqlite3_shutdown
  sqlite3_config_mempool 1000000
  sqlite3_initialize
  autoinstall_test_functions
} -shutdown {
  catch {db close}
  sqlite3_reset_auto_extension
  sqlite3_shutdown
  sqlite3_config_mempool 0
  sqlite3_initialize
}

# run_tests "crash_safe_append" -description {
#   Run crash.test with persistent journals on a SAFE_APPEND file-system.
# } -initialize {
#   rename crashsql sa_crashsql
#   proc crashsql {args} {
#     set options [lrange $args 0 [expr {[llength $args]-2}]]