1 files changed, 17 insertions, 9 deletions
diff --git a/lang/sql/sqlite/src/malloc.c b/lang/sql/sqlite/src/malloc.c
index 50fdf524..9c11d077 100644
--- a/lang/sql/sqlite/src/malloc.c
+++ b/lang/sql/sqlite/src/malloc.c
@@ -130,7 +130,8 @@ sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 n){
   sqlite3_int64 priorLimit;
   sqlite3_int64 excess;
 #ifndef SQLITE_OMIT_AUTOINIT
-  sqlite3_initialize();
+  int rc = sqlite3_initialize();
+  if( rc ) return -1;
 #endif
   sqlite3_mutex_enter(mem0.mutex);
   priorLimit = mem0.alarmThreshold;
@@ -266,7 +267,7 @@ static int mallocWithAlarm(int n, void **pp){
   sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, n);
   if( mem0.alarmCallback!=0 ){
     int nUsed = sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED);
-    if( nUsed+nFull >= mem0.alarmThreshold ){
+    if( nUsed >= mem0.alarmThreshold - nFull ){
       mem0.nearlyFull = 1;
       sqlite3MallocAlarm(nFull);
     }else{
@@ -432,7 +433,7 @@ void sqlite3ScratchFree(void *p){
 */
 #ifndef SQLITE_OMIT_LOOKASIDE
 static int isLookaside(sqlite3 *db, void *p){
-  return p && p>=db->lookaside.pStart && p<db->lookaside.pEnd;
+  return p>=db->lookaside.pStart && p<db->lookaside.pEnd;
 }
 #else
 #define isLookaside(A,B) 0
@@ -448,8 +449,9 @@ int sqlite3MallocSize(void *p){
   return sqlite3GlobalConfig.m.xSize(p);
 }
 int sqlite3DbMallocSize(sqlite3 *db, void *p){
-  assert( db==0 || sqlite3_mutex_held(db->mutex) );
-  if( db && isLookaside(db, p) ){
+  assert( db!=0 );
+  assert( sqlite3_mutex_held(db->mutex) );
+  if( isLookaside(db, p) ){
     return db->lookaside.sz;
   }else{
     assert( sqlite3MemdebugHasType(p, MEMTYPE_DB) );
@@ -483,6 +485,7 @@ void sqlite3_free(void *p){
 */
 void sqlite3DbFree(sqlite3 *db, void *p){
   assert( db==0 || sqlite3_mutex_held(db->mutex) );
+  if( p==0 ) return;
   if( db ){
     if( db->pnBytesFreed ){
       *db->pnBytesFreed += sqlite3DbMallocSize(db, p);
@@ -490,6 +493,10 @@ void sqlite3DbFree(sqlite3 *db, void *p){
     }
     if( isLookaside(db, p) ){
       LookasideSlot *pBuf = (LookasideSlot*)p;
+#if SQLITE_DEBUG
+      /* Trash all content in the buffer being freed */
+      memset(p, 0xaa, db->lookaside.sz);
+#endif
       pBuf->pNext = db->lookaside.pFree;
       db->lookaside.pFree = pBuf;
       db->lookaside.nOut--;
@@ -507,7 +514,7 @@ void sqlite3DbFree(sqlite3 *db, void *p){
 ** Change the size of an existing memory allocation
 */
 void *sqlite3Realloc(void *pOld, int nBytes){
-  int nOld, nNew;
+  int nOld, nNew, nDiff;
   void *pNew;
   if( pOld==0 ){
     return sqlite3Malloc(nBytes); /* IMP: R-28354-25769 */
@@ -530,9 +537,10 @@ void *sqlite3Realloc(void *pOld, int nBytes){
   }else if( sqlite3GlobalConfig.bMemstat ){
     sqlite3_mutex_enter(mem0.mutex);
     sqlite3StatusSet(SQLITE_STATUS_MALLOC_SIZE, nBytes);
-    if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED)+nNew-nOld >= 
-          mem0.alarmThreshold ){
-      sqlite3MallocAlarm(nNew-nOld);
+    nDiff = nNew - nOld;
+    if( sqlite3StatusValue(SQLITE_STATUS_MEMORY_USED) >= 
+          mem0.alarmThreshold-nDiff ){
+      sqlite3MallocAlarm(nDiff);
     }
     assert( sqlite3MemdebugHasType(pOld, MEMTYPE_HEAP) );
     assert( sqlite3MemdebugNoType(pOld, ~MEMTYPE_HEAP) );