Simplifications to btree.c in support of structural testing. Renamed the

"skip" field of the BtCursor object to "skipNext" to make it easier to
search for places where it is used. (CVS 6896)

FossilOrigin-Name: d3897235d77e48ad09f7edb0a7641458afa0a282

diff --git a/manifest b/manifest
index c013d56e2549806c16f4a10f3e53d557e687d3ce..c86fb8615b20d92e6e85c77c817608442774370e 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Remove\san\sassert()\sfrom\svdbeaux.c\sthat\smight\snot\sbe\strue\sif\sthe\sdatabase\nfile\sis\scorrupt.\s(CVS\s6895)
-D 2009-07-15T16:30:50
+C Simplifications\sto\sbtree.c\sin\ssupport\sof\sstructural\stesting.\s\sRenamed\sthe\n"skip"\sfield\sof\sthe\sBtCursor\sobject\sto\s"skipNext"\sto\smake\sit\seasier\sto\nsearch\sfor\splaces\swhere\sit\sis\sused.\s(CVS\s6896)
+D 2009-07-15T17:25:46
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in df9359da7a726ccb67a45db905c5447d5c00c6ef
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -106,9 +106,9 @@ F src/auth.c 802a9439dfa0b8c208b10055cba400e82ef18025
 F src/backup.c 6f1c2d9862c8a3feb7739dfcca02c1f5352e37f3
 F src/bitvec.c 0ef0651714728055d43de7a4cdd95e703fac0119
 F src/btmutex.c 9b899c0d8df3bd68f527b0afe03088321b696d3c
-F src/btree.c b5a8d21f6b21ab0068910d881b38a3c54ba7214d
+F src/btree.c a1fda2c54edd21079c60c34ee6973e0522c4ece2
 F src/btree.h e53a10fd31d16c60a86f03c9467a6f470aa3683b
-F src/btreeInt.h a568bf057aa249eb06fd31358b4393a5ac88c118
+F src/btreeInt.h 1c86297e69380f6577e7ae67452597dd8d5c2705
 F src/build.c 867028ee9f63f7bc8eb8d4a720bb98cf9b9a12b4
 F src/callback.c cb68b21b0d4ae7d11ae0e487933bce3323784dcf
 F src/complete.c 5ad5c6cd4548211867c204c41a126d73a9fbcea0
@@ -740,7 +740,7 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl 672f81d693a03f80f5ae60bfefacd8a349e76746
-P cfbeda1b3126503e9631471ce4713e25b007859f
-R d6155ec47b65f864575de01cbf0050eb
+P a42dc51e3bd258d5a357e557251fb2642708ceac
+R b79ce4fac444a551c4798dffd50747f8
 U drh
-Z 0b9e2d4ca82b865798da8f05eede3fbb
+Z d31e2bba272164e36061fcdc880b0bf2

diff --git a/manifest.uuid b/manifest.uuid
index 52a997eedd7359c02f6396808278264ab1d23bfe..996aaaa69661911d58850fa57b468c89d204f2dd 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-a42dc51e3bd258d5a357e557251fb2642708ceac
\ No newline at end of file
+d3897235d77e48ad09f7edb0a7641458afa0a282
\ No newline at end of file

diff --git a/src/btree.c b/src/btree.c
index 7592dc4f7dd787628cad608895cd9a6b1ce2d934..f7711d7d82c3115a647bb3599bd05e88d97f1aff 100644 (file)
--- a/src/btree.c
+++ b/src/btree.c
@@ -9,7 +9,7 @@
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** $Id: btree.c,v 1.688 2009/07/15 11:26:44 drh Exp $
+** $Id: btree.c,v 1.689 2009/07/15 17:25:46 drh Exp $
 **
 ** This file implements a external (disk-based) database using BTrees.
 ** See the header comment on "btreeInt.h" for additional information.
@@ -500,13 +500,13 @@ static void invalidateIncrblobCursors(
 static int btreeSetHasContent(BtShared *pBt, Pgno pgno){
   int rc = SQLITE_OK;
   if( !pBt->pHasContent ){
-    int nPage;
-    rc = sqlite3PagerPagecount(pBt->pPager, &nPage);
-    if( rc==SQLITE_OK ){
-      pBt->pHasContent = sqlite3BitvecCreate((u32)nPage);
-      if( !pBt->pHasContent ){
-        rc = SQLITE_NOMEM;
-      }
+    int nPage = 100;
+    sqlite3PagerPagecount(pBt->pPager, &nPage);
+    /* If sqlite3PagerPagecount() fails there is no harm because the
+    ** nPage variable is unchanged from its default value of 100 */
+    pBt->pHasContent = sqlite3BitvecCreate((u32)nPage);
+    if( !pBt->pHasContent ){
+      rc = SQLITE_NOMEM;
     }
   }
   if( rc==SQLITE_OK && pgno<=sqlite3BitvecSize(pBt->pHasContent) ){
@@ -548,6 +548,7 @@ static int saveCursorPosition(BtCursor *pCur){
   assert( cursorHoldsMutex(pCur) );
 
   rc = sqlite3BtreeKeySize(pCur, &pCur->nKey);
+  assert( rc==SQLITE_OK );  /* Cannot fail since pCur->eState==VALID */
 
   /* If this is an intKey table, then the above call to BtreeKeySize()
   ** stores the integer key in pCur->nKey. In this case this value is
@@ -555,7 +556,7 @@ static int saveCursorPosition(BtCursor *pCur){
   ** table, then malloc space for and store the pCur->nKey bytes of key 
   ** data.
   */
-  if( rc==SQLITE_OK && 0==pCur->apPage[0]->intKey){
+  if( 0==pCur->apPage[0]->intKey ){
     void *pKey = sqlite3Malloc( (int)pCur->nKey );
     if( pKey ){
       rc = sqlite3BtreeKey(pCur, 0, (int)pCur->nKey, pKey);
@@ -658,10 +659,10 @@ static int btreeRestoreCursorPosition(BtCursor *pCur){
   assert( cursorHoldsMutex(pCur) );
   assert( pCur->eState>=CURSOR_REQUIRESEEK );
   if( pCur->eState==CURSOR_FAULT ){
-    return pCur->skip;
+    return pCur->skipNext;
   }
   pCur->eState = CURSOR_INVALID;
-  rc = btreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &pCur->skip);
+  rc = btreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &pCur->skipNext);
   if( rc==SQLITE_OK ){
     sqlite3_free(pCur->pKey);
     pCur->pKey = 0;
@@ -691,7 +692,7 @@ int sqlite3BtreeCursorHasMoved(BtCursor *pCur, int *pHasMoved){
     *pHasMoved = 1;
     return rc;
   }
-  if( pCur->eState!=CURSOR_VALID || pCur->skip!=0 ){
+  if( pCur->eState!=CURSOR_VALID || pCur->skipNext!=0 ){
     *pHasMoved = 1;
   }else{
     *pHasMoved = 0;
@@ -2433,9 +2434,8 @@ int sqlite3BtreeBeginTrans(Btree *p, int wrflag){
   /* Any read-only or read-write transaction implies a read-lock on 
   ** page 1. So if some other shared-cache client already has a write-lock 
   ** on page 1, the transaction cannot be opened. */
-  if( SQLITE_OK!=(rc = querySharedCacheTableLock(p, MASTER_ROOT, READ_LOCK)) ){
-    goto trans_begun;
-  }
+  rc = querySharedCacheTableLock(p, MASTER_ROOT, READ_LOCK);
+  if( SQLITE_OK!=rc ) goto trans_begun;
 
   do {
     /* Call lockBtree() until either pBt->pPage1 is populated or
@@ -3091,7 +3091,7 @@ void sqlite3BtreeTripAllCursors(Btree *pBtree, int errCode){
     int i;
     sqlite3BtreeClearCursor(p);
     p->eState = CURSOR_FAULT;
-    p->skip = errCode;
+    p->skipNext = errCode;
     for(i=0; i<=p->iPage; i++){
       releasePage(p->apPage[i]);
       p->apPage[i] = 0;
@@ -4011,8 +4011,8 @@ static int moveToRoot(BtCursor *pCur){
   assert( CURSOR_FAULT   > CURSOR_REQUIRESEEK );
   if( pCur->eState>=CURSOR_REQUIRESEEK ){
     if( pCur->eState==CURSOR_FAULT ){
-      assert( pCur->skip!=SQLITE_OK );
-      return pCur->skip;
+      assert( pCur->skipNext!=SQLITE_OK );
+      return pCur->skipNext;
     }
     sqlite3BtreeClearCursor(pCur);
   }
@@ -4024,9 +4024,8 @@ static int moveToRoot(BtCursor *pCur){
     }
     pCur->iPage = 0;
   }else{
-    if( 
-      SQLITE_OK!=(rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->apPage[0]))
-    ){
+    rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->apPage[0]);
+    if( rc!=SQLITE_OK ){
       pCur->eState = CURSOR_INVALID;
       return rc;
     }
@@ -4423,12 +4422,12 @@ int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
     *pRes = 1;
     return SQLITE_OK;
   }
-  if( pCur->skip>0 ){
-    pCur->skip = 0;
+  if( pCur->skipNext>0 ){
+    pCur->skipNext = 0;
     *pRes = 0;
     return SQLITE_OK;
   }
-  pCur->skip = 0;
+  pCur->skipNext = 0;
 
   pPage = pCur->apPage[pCur->iPage];
   idx = ++pCur->aiIdx[pCur->iPage];
@@ -4491,12 +4490,12 @@ int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
     *pRes = 1;
     return SQLITE_OK;
   }
-  if( pCur->skip<0 ){
-    pCur->skip = 0;
+  if( pCur->skipNext<0 ){
+    pCur->skipNext = 0;
     *pRes = 0;
     return SQLITE_OK;
   }
-  pCur->skip = 0;
+  pCur->skipNext = 0;
 
   pPage = pCur->apPage[pCur->iPage];
   assert( pPage->isInit );
@@ -4628,7 +4627,6 @@ static int allocateBtreePage(
       }
 
       k = get4byte(&pTrunk->aData[4]);
-      testcase( k==(u32)(pBt->usableSize/4 - 2) );
       if( k==0 && !searchList ){
         /* The trunk has no leaves and the list is not being searched. 
         ** So extract the trunk page itself and use it as the newly 
@@ -5187,7 +5185,7 @@ static int dropCell(MemPage *pPage, int idx, int sz){
   data = pPage->aData;
   ptr = &data[pPage->cellOffset + 2*idx];
   pc = get2byte(ptr);
-  if( NEVER(pc<pPage->hdrOffset+6+pPage->childPtrSize)
+  if( (pc<pPage->hdrOffset+6+pPage->childPtrSize)
      || (pc+sz>pPage->pBt->usableSize) ){
     return SQLITE_CORRUPT_BKPT;
   }
@@ -6430,8 +6428,8 @@ int sqlite3BtreeInsert(
   }
 
   if( pCur->eState==CURSOR_FAULT ){
-    assert( pCur->skip!=SQLITE_OK );
-    return pCur->skip;
+    assert( pCur->skipNext!=SQLITE_OK );
+    return pCur->skipNext;
   }
 
   /* Save the positions of any other cursors open on this table.
@@ -6445,11 +6443,11 @@ int sqlite3BtreeInsert(
   ** doing any work. To avoid thwarting these optimizations, it is important
   ** not to clear the cursor here.
   */
-  if(
-    SQLITE_OK!=(rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur)) || (!loc &&
-    SQLITE_OK!=(rc = btreeMoveto(pCur, pKey, nKey, appendBias, &loc))
-  )){
-    return rc;
+  rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur);
+  if( rc ) return rc;
+  if( !loc ){
+    rc = btreeMoveto(pCur, pKey, nKey, appendBias, &loc);
+    if( rc ) return rc;
   }
   assert( pCur->eState==CURSOR_VALID || (pCur->eState==CURSOR_INVALID && loc) );
 
@@ -6580,9 +6578,8 @@ int sqlite3BtreeDelete(BtCursor *pCur){
   ** balancing the tree following the delete operation easier.  */
   if( !pPage->leaf ){
     int notUsed;
-    if( SQLITE_OK!=(rc = sqlite3BtreePrevious(pCur, &notUsed)) ){
-      return rc;
-    }
+    rc = sqlite3BtreePrevious(pCur, &notUsed);
+    if( rc ) return rc;
   }
 
   /* Save the positions of any other cursors open on this table before

diff --git a/src/btreeInt.h b/src/btreeInt.h
index a051587b670b21b3f644e933b685dfe74fbc272f..239439b4ad9e38288ec252e0d373a14b64749195 100644 (file)
--- a/src/btreeInt.h
+++ b/src/btreeInt.h
@@ -9,7 +9,7 @@
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
-** $Id: btreeInt.h,v 1.51 2009/07/09 05:07:38 danielk1977 Exp $
+** $Id: btreeInt.h,v 1.52 2009/07/15 17:25:46 drh Exp $
 **
 ** This file implements a external (disk-based) database using BTrees.
 ** For a detailed discussion of BTrees, refer to
@@ -492,7 +492,7 @@ struct BtCursor {
   u8 eState;                /* One of the CURSOR_XXX constants (see below) */
   void *pKey;      /* Saved key that was cursor's last known position */
   i64 nKey;        /* Size of pKey, or last integer key */
-  int skip;        /* (skip<0) -> Prev() is a no-op. (skip>0) -> Next() is */
+  int skipNext;    /* Prev() is noop if negative. Next() is noop if positive */
 #ifndef SQLITE_OMIT_INCRBLOB
   u8 isIncrblobHandle;      /* True if this cursor is an incr. io handle */
   Pgno *aOverflow;          /* Cache of overflow page locations */
@@ -638,4 +638,3 @@ struct IntegrityCk {
 #define put2byte(p,v) ((p)[0] = (u8)((v)>>8), (p)[1] = (u8)(v))
 #define get4byte sqlite3Get4byte
 #define put4byte sqlite3Put4byte
-