safemalloc.c

php-4.4.7学习linux时下载的源代码

  DBUG_PRINT("enter",("ptr: %lx",pPtr));

  if (!sf_malloc_quick)
    (void) _sanity (sFile, uLine);

  if ((!pPtr && (myflags & MY_ALLOW_ZERO_PTR)) ||
      check_ptr("Freeing",(byte*) pPtr,sFile,uLine))
    DBUG_VOID_RETURN;

  /* Calculate the address of the remember structure */
  pRec = (struct remember *) ((byte*) pPtr-sizeof(struct irem)-
			      sf_malloc_prehunc);

  /* Check to make sure that we have a real remember structure	*/
  /* Note: this test could fail for four reasons:		*/
  /*	(1) The memory was already free'ed			*/
  /*	(2) The memory was never new'ed				*/
  /*	(3) There was an underrun				*/
  /*	(4) A stray pointer hit this location			*/

  if (*((long*) ((char*) &pRec -> lSpecialValue+sf_malloc_prehunc))
      != MAGICKEY)
  {
    fprintf (stderr, "Freeing unallocated data at line %d, '%s'\n",
	     uLine, sFile);
    DBUG_PRINT("safe",("Unallocated data at line %d, '%s'",uLine,sFile));
    (void) fflush(stderr);
    DBUG_VOID_RETURN;
  }

  /* Remove this structure from the linked list */
  pthread_mutex_lock(&THR_LOCK_malloc);
  if (pRec -> pPrev) {
    pRec -> pPrev -> pNext = pRec -> pNext;
  } else {
    pRememberRoot = pRec -> pNext;
  }
  if (pRec -> pNext) {
    pRec -> pNext -> pPrev = pRec -> pPrev;
  }
  /* Handle the statistics */
  lCurMemory -= pRec -> uDataSize;
  cNewCount--;
  pthread_mutex_unlock(&THR_LOCK_malloc);

#ifndef HAVE_purify
  /* Mark this data as free'ed */
  bfill(&pRec->aData[sf_malloc_prehunc],pRec->uDataSize,(pchar) FREE_VAL);
#endif
  *((long*) ((char*) &pRec -> lSpecialValue+sf_malloc_prehunc)) = ~MAGICKEY;

  /* Actually free the memory */
  free ((my_string ) pRec);
  DBUG_VOID_RETURN;
}

	/* Check if we have a wrong  pointer */

static int check_ptr(const char *where, byte *ptr, const char *sFile,
		     uint uLine)
{
  if (!ptr)
  {
    fprintf (stderr, "%s NULL pointer at line %d, '%s'\n",
	     where,uLine, sFile);
    DBUG_PRINT("safe",("Null pointer at line %d '%s'", uLine, sFile));
    (void) fflush(stderr);
    return 1;
  }
#ifndef _MSC_VER
  if ((long) ptr & (MY_ALIGN(1,sizeof(char *))-1))
  {
    fprintf (stderr, "%s wrong aligned pointer at line %d, '%s'\n",
	     where,uLine, sFile);
    DBUG_PRINT("safe",("Wrong aligned pointer at line %d, '%s'",
		       uLine,sFile));
    (void) fflush(stderr);
    return 1;
  }
#endif
  if (ptr < sf_min_adress || ptr > sf_max_adress)
  {
    fprintf (stderr, "%s pointer out of range at line %d, '%s'\n",
	     where,uLine, sFile);
    DBUG_PRINT("safe",("Pointer out of range at line %d '%s'",
		       uLine,sFile));
    (void) fflush(stderr);
    return 1;
  }
  return 0;
}


/*
 * TERMINATE(FILE *file)
 *	Report on all the memory pieces that have not been
 *	free'ed as well as the statistics.
 */

void TERMINATE (FILE *file)
{
  struct remember *pPtr;
  DBUG_ENTER("TERMINATE");
  pthread_mutex_lock(&THR_LOCK_malloc);

  /* Report the difference between number of calls to  */
  /* NEW and the number of calls to FREE.  >0 means more	 */
  /* NEWs than FREEs.  <0, etc.				 */

  if (cNewCount)
  {
    if (file)
    {
      fprintf (file, "cNewCount: %d\n", cNewCount);
      (void) fflush(file);
    }
    DBUG_PRINT("safe",("cNewCount: %d",cNewCount));
  }

  /* Report on all the memory that was allocated with NEW	 */
  /* but not free'ed with FREE.				 */

  if ((pPtr=pRememberRoot))
  {
    if (file)
    {
      fprintf(file, "Memory that was not free'ed (%ld bytes):\n",lCurMemory);
      (void) fflush(file);
    }
    DBUG_PRINT("safe",("Memory that was not free'ed (%ld bytes):",lCurMemory));
    while (pPtr)
    {
      if (file)
      {
	fprintf (file,
		 "\t%6u bytes at 0x%09lx, allocated at line %4u in '%s'\n",
		 pPtr -> uDataSize,
		 (ulong) &(pPtr -> aData[sf_malloc_prehunc]),
		 pPtr -> uLineNum, pPtr -> sFileName);
	(void) fflush(file);
      }
      DBUG_PRINT("safe",
		 ("%6u bytes at 0x%09lx, allocated at line %4d in '%s'",
		  pPtr -> uDataSize, &(pPtr -> aData[sf_malloc_prehunc]),
		  pPtr -> uLineNum, pPtr -> sFileName));
      pPtr = pPtr -> pNext;
    }
  }
  /* Report the memory usage statistics */
  if (file)
  {
    fprintf (file, "Maximum memory usage: %ld bytes (%ldk)\n",
	     lMaxMemory, (lMaxMemory + 1023L) / 1024L);
    (void) fflush(file);
  }
  DBUG_PRINT("safe",("Maximum memory usage: %ld bytes (%ldk)",
		     lMaxMemory, (lMaxMemory + 1023L) / 1024L));
  pthread_mutex_unlock(&THR_LOCK_malloc);
  DBUG_VOID_RETURN;
}


	/* Returns 0 if chunk is ok */

static int _checkchunk (register struct remember *pRec, const char *sFile,
			uint uLine)
{
  reg1 uint uSize;
  reg2 my_string magicp;
  reg3 int flag=0;

  /* Check for a possible underrun */
  if (*((long*) ((char*) &pRec -> lSpecialValue+sf_malloc_prehunc))
      != MAGICKEY)
  {
    fprintf (stderr, "Memory allocated at %s:%d was underrun,",
	     pRec -> sFileName, pRec -> uLineNum);
    fprintf (stderr, " discovered at %s:%d\n", sFile, uLine);
    (void) fflush(stderr);
    DBUG_PRINT("safe",("Underrun at %lx, allocated at %s:%d",
		       &(pRec -> aData[sf_malloc_prehunc]),
		       pRec -> sFileName,
		       pRec -> uLineNum));
    flag=1;
  }

  /* Check for a possible overrun */
  uSize = pRec -> uDataSize;
  magicp = &(pRec -> aData[uSize+sf_malloc_prehunc]);
  if (*magicp++ != MAGICEND0 ||
      *magicp++ != MAGICEND1 ||
      *magicp++ != MAGICEND2 ||
      *magicp++ != MAGICEND3)
  {
    fprintf (stderr, "Memory allocated at %s:%d was overrun,",
	     pRec -> sFileName, pRec -> uLineNum);
    fprintf (stderr, " discovered at '%s:%d'\n", sFile, uLine);
    (void) fflush(stderr);
    DBUG_PRINT("safe",("Overrun at %lx, allocated at %s:%d",
		       &(pRec -> aData[sf_malloc_prehunc]),
		       pRec -> sFileName,
		       pRec -> uLineNum));
    flag=1;
  }
  return(flag);
}


	/* Returns how many wrong chunks */

int _sanity (const char *sFile, uint uLine)
{
  reg1 struct remember *pTmp;
  reg2 int flag=0;
  uint count=0;

  pthread_mutex_lock(&THR_LOCK_malloc);
  count=cNewCount;
  for (pTmp = pRememberRoot; pTmp != NULL && count-- ; pTmp = pTmp -> pNext)
    flag+=_checkchunk (pTmp, sFile, uLine);
  pthread_mutex_unlock(&THR_LOCK_malloc);
  if (count || pTmp)
  {
    const char *format="Safemalloc link list destroyed, discovered at '%s:%d'";
    fprintf (stderr, format, sFile, uLine); fputc('\n',stderr);
    (void) fflush(stderr);
    DBUG_PRINT("safe",(format, sFile, uLine));
    flag=1;
  }
  return flag;
} /* _sanity */


	/* malloc and copy */

gptr _my_memdup(const byte *from, uint length, const char *sFile, uint uLine,
		myf MyFlags)
{
  gptr ptr;
  if ((ptr=_mymalloc(length,sFile,uLine,MyFlags)) != 0)
    memcpy((byte*) ptr, (byte*) from,(size_t) length);
  return(ptr);
} /*_my_memdup */


my_string _my_strdup(const char *from, const char *sFile, uint uLine,
		     myf MyFlags)
{
  gptr ptr;
  uint length=(uint) strlen(from)+1;
  if ((ptr=_mymalloc(length,sFile,uLine,MyFlags)) != 0)
    memcpy((byte*) ptr, (byte*) from,(size_t) length);
  return((my_string) ptr);
} /* _my_strdup */