1 files changed, 26 insertions, 15 deletions

diff --git a/src/bitvec.c b/src/bitvec.c
index b6420a7f2..616c2adc5 100644
--- a/src/bitvec.c
+++ b/src/bitvec.c
@@ -34,7 +34,7 @@
 ** start of a transaction, and is thus usually less than a few thousand,
 ** but can be as large as 2 billion for a really big database.
 **
-** @(#) $Id: bitvec.c,v 1.14 2009/04/01 23:49:04 drh Exp $
+** @(#) $Id: bitvec.c,v 1.15 2009/06/02 21:31:39 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -209,15 +209,20 @@ bitvec_set_rehash:
   if( p->nSet>=BITVEC_MXHASH ){
     unsigned int j;
     int rc;
-    u32 aiValues[BITVEC_NINT];
-    memcpy(aiValues, p->u.aHash, sizeof(aiValues));
-    memset(p->u.apSub, 0, sizeof(aiValues));
-    p->iDivisor = (p->iSize + BITVEC_NPTR - 1)/BITVEC_NPTR;
-    rc = sqlite3BitvecSet(p, i);
-    for(j=0; j<BITVEC_NINT; j++){
-      if( aiValues[j] ) rc |= sqlite3BitvecSet(p, aiValues[j]);
+    u32 *aiValues = sqlite3StackAllocRaw(0, sizeof(p->u.aHash));
+    if( aiValues==0 ){
+      return SQLITE_NOMEM;
+    }else{
+      memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
+      memset(p->u.apSub, 0, sizeof(p->u.apSub));
+      p->iDivisor = (p->iSize + BITVEC_NPTR - 1)/BITVEC_NPTR;
+      rc = sqlite3BitvecSet(p, i);
+      for(j=0; j<BITVEC_NINT; j++){
+        if( aiValues[j] ) rc |= sqlite3BitvecSet(p, aiValues[j]);
+      }
+      sqlite3StackFree(0, aiValues);
+      return rc;
     }
-    return rc;
   }
 bitvec_set_end:
   p->nSet++;
@@ -227,8 +232,11 @@ bitvec_set_end:
 
 /*
 ** Clear the i-th bit.
+**
+** pBuf must be a pointer to at least BITVEC_SZ bytes of temporary storage
+** that BitvecClear can use to rebuilt its hash table.
 */
-void sqlite3BitvecClear(Bitvec *p, u32 i){
+void sqlite3BitvecClear(Bitvec *p, u32 i, void *pBuf){
   assert( p!=0 );
   assert( i>0 );
   i--;
@@ -244,9 +252,9 @@ void sqlite3BitvecClear(Bitvec *p, u32 i){
     p->u.aBitmap[i/BITVEC_SZELEM] &= ~(1 << (i&(BITVEC_SZELEM-1)));
   }else{
     unsigned int j;
-    u32 aiValues[BITVEC_NINT];
-    memcpy(aiValues, p->u.aHash, sizeof(aiValues));
-    memset(p->u.aHash, 0, sizeof(aiValues));
+    u32 *aiValues = pBuf;
+    memcpy(aiValues, p->u.aHash, sizeof(p->u.aHash));
+    memset(p->u.aHash, 0, sizeof(p->u.aHash));
     p->nSet = 0;
     for(j=0; j<BITVEC_NINT; j++){
       if( aiValues[j] && aiValues[j]!=(i+1) ){
@@ -330,12 +338,14 @@ int sqlite3BitvecBuiltinTest(int sz, int *aOp){
   unsigned char *pV = 0;
   int rc = -1;
   int i, nx, pc, op;
+  void *pTmpSpace;
 
   /* Allocate the Bitvec to be tested and a linear array of
   ** bits to act as the reference */
   pBitvec = sqlite3BitvecCreate( sz );
   pV = sqlite3_malloc( (sz+7)/8 + 1 );
-  if( pBitvec==0 || pV==0 ) goto bitvec_end;
+  pTmpSpace = sqlite3_malloc(BITVEC_SZ);
+  if( pBitvec==0 || pV==0 || pTmpSpace==0  ) goto bitvec_end;
   memset(pV, 0, (sz+7)/8 + 1);
 
   /* Run the program */
@@ -368,7 +378,7 @@ int sqlite3BitvecBuiltinTest(int sz, int *aOp){
       }
     }else{
       CLEARBIT(pV, (i+1));
-      sqlite3BitvecClear(pBitvec, i+1);
+      sqlite3BitvecClear(pBitvec, i+1, pTmpSpace);
     }
   }
 
@@ -389,6 +399,7 @@ int sqlite3BitvecBuiltinTest(int sz, int *aOp){
 
   /* Free allocated structure */
 bitvec_end:
+  sqlite3_free(pTmpSpace);
   sqlite3_free(pV);
   sqlite3BitvecDestroy(pBitvec);
   return rc;