Further reductions in the amount of stack space required. (CVS 6707)

FossilOrigin-Name: 04bad9eb6dd8bf7cafc9f3918b676e95d5b1c984

5 files changed, 80 insertions, 55 deletions

diff --git a/src/backup.c b/src/backup.c
index e0ab5d882..a1cb85503 100644
--- a/src/backup.c
+++ b/src/backup.c
@@ -12,7 +12,7 @@
 ** This file contains the implementation of the sqlite3_backup_XXX() 
 ** API functions and the related features.
 **
-** $Id: backup.c,v 1.15 2009/05/14 19:26:51 drh Exp $
+** $Id: backup.c,v 1.16 2009/06/02 21:31:39 drh Exp $
 */
 #include "sqliteInt.h"
 #include "btreeInt.h"
@@ -91,15 +91,24 @@ static Btree *findBtree(sqlite3 *pErrorDb, sqlite3 *pDb, const char *zDb){
   int i = sqlite3FindDbName(pDb, zDb);
 
   if( i==1 ){
-    Parse sParse;
-    memset(&sParse, 0, sizeof(sParse));
-    sParse.db = pDb;
-    if( sqlite3OpenTempDatabase(&sParse) ){
-      sqlite3ErrorClear(&sParse);
-      sqlite3Error(pErrorDb, sParse.rc, "%s", sParse.zErrMsg);
+    Parse *pParse;
+    int rc = 0;
+    pParse = sqlite3StackAllocZero(pErrorDb, sizeof(*pParse));
+    if( pParse==0 ){
+      sqlite3Error(pErrorDb, SQLITE_NOMEM, "out of memory");
+      rc = SQLITE_NOMEM;
+    }else{
+      pParse->db = pDb;
+      if( sqlite3OpenTempDatabase(pParse) ){
+        sqlite3ErrorClear(pParse);
+        sqlite3Error(pErrorDb, pParse->rc, "%s", pParse->zErrMsg);
+        rc = SQLITE_ERROR;
+      }
+      sqlite3StackFree(pErrorDb, pParse);
+    }
+    if( rc ){
       return 0;
     }
-    assert( sParse.zErrMsg==0 );
   }
 
   if( i<0 ){
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;
diff --git a/src/pager.c b/src/pager.c
index 274949043..16cc70c81 100644
--- a/src/pager.c
+++ b/src/pager.c
@@ -18,7 +18,7 @@
 ** file simultaneously, or one process from reading the database while
 ** another is writing.
 **
-** @(#) $Id: pager.c,v 1.590 2009/05/29 11:57:38 drh Exp $
+** @(#) $Id: pager.c,v 1.591 2009/06/02 21:31:39 drh Exp $
 */
 #ifndef SQLITE_OMIT_DISKIO
 #include "sqliteInt.h"
@@ -5166,7 +5166,8 @@ int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno, int isCommit){
     rc = sqlite3PagerGet(pPager, needSyncPgno, &pPgHdr);
     if( rc!=SQLITE_OK ){
       if( pPager->pInJournal && needSyncPgno<=pPager->dbOrigSize ){
-        sqlite3BitvecClear(pPager->pInJournal, needSyncPgno);
+        assert( pPager->pTmpSpace!=0 );
+        sqlite3BitvecClear(pPager->pInJournal, needSyncPgno, pPager->pTmpSpace);
       }
       return rc;
     }
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index d6b150630..eaf35872f 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -11,7 +11,7 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.880 2009/06/01 18:18:21 drh Exp $
+** @(#) $Id: sqliteInt.h,v 1.881 2009/06/02 21:31:39 drh Exp $
 */
 #ifndef _SQLITEINT_H_
 #define _SQLITEINT_H_
@@ -2455,7 +2455,7 @@ void sqlite3EndTable(Parse*,Token*,Token*,Select*);
 Bitvec *sqlite3BitvecCreate(u32);
 int sqlite3BitvecTest(Bitvec*, u32);
 int sqlite3BitvecSet(Bitvec*, u32);
-void sqlite3BitvecClear(Bitvec*, u32);
+void sqlite3BitvecClear(Bitvec*, u32, void*);
 void sqlite3BitvecDestroy(Bitvec*);
 u32 sqlite3BitvecSize(Bitvec*);
 int sqlite3BitvecBuiltinTest(int,int*);
diff --git a/src/vtab.c b/src/vtab.c
index 3c7316c02..10a168162 100644
--- a/src/vtab.c
+++ b/src/vtab.c
@@ -11,7 +11,7 @@
 *************************************************************************
 ** This file contains code used to help implement virtual tables.
 **
-** $Id: vtab.c,v 1.89 2009/05/20 20:10:47 drh Exp $
+** $Id: vtab.c,v 1.90 2009/06/02 21:31:39 drh Exp $
 */
 #ifndef SQLITE_OMIT_VIRTUALTABLE
 #include "sqliteInt.h"
@@ -550,7 +550,7 @@ int sqlite3VtabCallCreate(sqlite3 *db, int iDb, const char *zTab, char **pzErr){
 ** virtual table module.
 */
 int sqlite3_declare_vtab(sqlite3 *db, const char *zCreateTable){
-  Parse sParse;
+  Parse *pParse;
 
   int rc = SQLITE_OK;
   Table *pTab;
@@ -565,33 +565,37 @@ int sqlite3_declare_vtab(sqlite3 *db, const char *zCreateTable){
   }
   assert((pTab->tabFlags & TF_Virtual)!=0 && pTab->nCol==0 && pTab->aCol==0);
 
-  memset(&sParse, 0, sizeof(Parse));
-  sParse.declareVtab = 1;
-  sParse.db = db;
-
-  if( 
-      SQLITE_OK == sqlite3RunParser(&sParse, zCreateTable, &zErr) && 
-      sParse.pNewTable && 
-      !sParse.pNewTable->pSelect && 
-      (sParse.pNewTable->tabFlags & TF_Virtual)==0
-  ){
-    pTab->aCol = sParse.pNewTable->aCol;
-    pTab->nCol = sParse.pNewTable->nCol;
-    sParse.pNewTable->nCol = 0;
-    sParse.pNewTable->aCol = 0;
-    db->pVTab = 0;
-  } else {
-    sqlite3Error(db, SQLITE_ERROR, zErr);
-    sqlite3DbFree(db, zErr);
-    rc = SQLITE_ERROR;
-  }
-  sParse.declareVtab = 0;
-
-  if( sParse.pVdbe ){
-    sqlite3VdbeFinalize(sParse.pVdbe);
+  pParse = sqlite3StackAllocZero(db, sizeof(*pParse));
+  if( pParse==0 ){
+    rc = SQLITE_NOMEM;
+  }else{
+    pParse->declareVtab = 1;
+    pParse->db = db;
+  
+    if( 
+        SQLITE_OK == sqlite3RunParser(pParse, zCreateTable, &zErr) && 
+        pParse->pNewTable && 
+        !pParse->pNewTable->pSelect && 
+        (pParse->pNewTable->tabFlags & TF_Virtual)==0
+    ){
+      pTab->aCol = pParse->pNewTable->aCol;
+      pTab->nCol = pParse->pNewTable->nCol;
+      pParse->pNewTable->nCol = 0;
+      pParse->pNewTable->aCol = 0;
+      db->pVTab = 0;
+    } else {
+      sqlite3Error(db, SQLITE_ERROR, zErr);
+      sqlite3DbFree(db, zErr);
+      rc = SQLITE_ERROR;
+    }
+    pParse->declareVtab = 0;
+  
+    if( pParse->pVdbe ){
+      sqlite3VdbeFinalize(pParse->pVdbe);
+    }
+    sqlite3DeleteTable(pParse->pNewTable);
+    sqlite3StackFree(db, pParse);
   }
-  sqlite3DeleteTable(sParse.pNewTable);
-  sParse.pNewTable = 0;
 
   assert( (rc&0xff)==rc );
   rc = sqlite3ApiExit(db, rc);