coverted my_thread_init() /end to use my_malloc()/my_free() to help track

down replication corruption


dbug/dbug.c:
  fixed DBUG_ macros to not crash if my_thread_init() had not been called
include/my_sys.h:
  keep track of shutdown, main, and signal threads for safemalloc
mysys/my_static.h:
  keep track of thread in safemalloc blocks
mysys/my_thr_init.c:
  use my_malloc()/my_free() in my_thread_init()
mysys/safemalloc.c:
  keep track of threads
  do not fuss if main,signal, or shutdown thread still has allocated blocks 
   when we call TERMINATE() as some blocks are freed later and there is no
   easy way to make TERMINATE() wait for those threads
sql/mysqld.cc:
  keep track of signal, main, and shutdown threads

mysys/safemalloc.c

@@ -73,14 +73,25 @@
 #include "mysys_err.h"
 
 ulonglong safemalloc_mem_limit = ~(ulonglong)0;
+pthread_t shutdown_th=0,main_th=0,signal_th=0;
 
 #define pNext		tInt._pNext
 #define pPrev		tInt._pPrev
 #define sFileName	tInt._sFileName
 #define uLineNum	tInt._uLineNum
 #define uDataSize	tInt._uDataSize
+#define thread_id       tInt.thread_id
 #define lSpecialValue	tInt._lSpecialValue
 
+#ifndef PEDANTIC_SAFEMALLOC
+static int sf_malloc_tampered = 0; /* set to 1 after TERMINATE() if we had
+				    to fiddle with cNewCount and the linked
+				    list of blocks so that _sanity() will
+				    not fuss when it is not supposed to
+				 */
+#endif
+				   
+
 	/* Static functions prototypes */
 
 static int check_ptr(const char *where, byte *ptr, const char *sFile,
@@ -174,6 +185,7 @@ gptr _mymalloc (uint uSize, const char *sFile, uint uLine, myf MyFlags)
     pTmp -> sFileName = (my_string) sFile;
     pTmp -> uLineNum = uLine;
     pTmp -> uDataSize = uSize;
+    pTmp->thread_id = pthread_self();
     pTmp -> pPrev = NULL;
 
     /* Add this remember structure to the linked list */
@@ -359,6 +371,12 @@ static int check_ptr(const char *where, byte *ptr, const char *sFile,
   return 0;
 }
 
+static int legal_leak(struct remember* pPtr)
+{
+ return pthread_self() == pPtr->thread_id || main_th == pPtr->thread_id
+	    || shutdown_th == pPtr->thread_id
+   || signal_th == pPtr->thread_id;
+}
 
 /*
  * TERMINATE(FILE *file)
@@ -376,6 +394,47 @@ void TERMINATE (FILE *file)
   /* NEW and the number of calls to FREE.  >0 means more	 */
   /* NEWs than FREEs.  <0, etc.				 */
 
+#ifndef PEDANTIC_SAFEMALLOC
+  /* Avoid false alarms for blocks that we cannot free before my_end()
+     This does miss some positives, but that is ok. This will only miss
+     failures to free things allocated in the main thread which 
+     performs only one-time allocations. If you really need to
+     debug memory allocations in the main thread,
+     #define PEDANTIC_SAFEMALLOC
+  */
+  if ((pPtr=pRememberRoot))
+  {
+    while (pPtr)
+    {
+      if (legal_leak(pPtr))
+      {
+	sf_malloc_tampered=1;
+	cNewCount--;
+	lCurMemory -= pPtr->uDataSize;
+	if (pPtr->pPrev)
+	{
+	  struct remember* tmp;
+	  tmp = pPtr->pPrev->pNext = pPtr->pNext;
+	  if (tmp)
+	   tmp->pPrev = pPtr->pPrev; 
+	  pPtr->pNext = pPtr->pPrev = 0;
+	  pPtr = tmp;
+	}
+	else
+	{
+	  pRememberRoot = pPtr->pNext;
+	  pPtr->pNext = pPtr->pPrev = 0;
+	  pPtr = pRememberRoot;
+	  if (pPtr)
+	    pPtr->pPrev=0;
+	}
+      }
+      else
+	pPtr = pPtr->pNext;
+    }
+  }
+#endif  
+  
   if (cNewCount)
   {
     if (file)
@@ -402,10 +461,14 @@ void TERMINATE (FILE *file)
       if (file)
       {
 	fprintf (file,
-		 "\t%6u bytes at 0x%09lx, allocated at line %4u in '%s'\n",
+		 "\t%6u bytes at 0x%09lx, allocated at line %4u in '%s'",
 		 pPtr -> uDataSize,
 		 (ulong) &(pPtr -> aData[sf_malloc_prehunc]),
 		 pPtr -> uLineNum, pPtr -> sFileName);
+#ifdef THREAD
+	fprintf(file, " in thread %ld", pPtr->thread_id);
+#endif
+	fprintf(file, "\n");
 	(void) fflush(file);
       }
       DBUG_PRINT("safe",
@@ -484,6 +547,10 @@ int _sanity (const char *sFile, uint uLine)
   uint count=0;
 
   pthread_mutex_lock(&THR_LOCK_malloc);
+#ifndef PEDANTIC_SAFEMALLOC  
+  if (sf_malloc_tampered && cNewCount < 0)
+    cNewCount=0;
+#endif  
   count=cNewCount;
   for (pTmp = pRememberRoot; pTmp != NULL && count-- ; pTmp = pTmp -> pNext)
     flag+=_checkchunk (pTmp, sFile, uLine);
@@ -492,6 +559,7 @@ int _sanity (const char *sFile, uint uLine)
   {
     const char *format="Safemalloc link list destroyed, discovered at '%s:%d'";
     fprintf (stderr, format, sFile, uLine); fputc('\n',stderr);
+    fprintf (stderr, "root=%p,count=%d,pTmp=%p\n", pRememberRoot,count,pTmp);
     (void) fflush(stderr);
     DBUG_PRINT("safe",(format, sFile, uLine));
     flag=1;