Change the definition of the BtCursor.skipNext field so that it is undefined

for states CURSOR_VALID and CURSOR_INVALID.

FossilOrigin-Name: 6089d5dba73437d787259033e94a38cf1b0c87cac4a89c27e69d8239c22f496e

diff --git a/manifest b/manifest
index 33af54aca5dd1914a7980d21d376510fc1b1792e..45e936b7cd9a20999ec1b4ffd4bd024c40995163 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Improvements\sto\sthe\s".eqp\strace"\scommand\sin\sthe\sCLI\sso\sthat\sit\sensures\sthat\nthe\sschema\shas\sbeen\sread\sprior\sto\sactiving\sthe\stracing\sfeature,\sto\savoid\ncluttering\sthe\soutput\swith\sa\strace\sof\sthe\sschema\sparse.
-D 2019-01-27T19:50:56.340
+C Change\sthe\sdefinition\sof\sthe\sBtCursor.skipNext\sfield\sso\sthat\sit\sis\sundefined\nfor\sstates\sCURSOR_VALID\sand\sCURSOR_INVALID.
+D 2019-01-28T00:42:06.088
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F Makefile.in 9947eae873c07ae894d4c8633b76c0a0daca7b9fd54401096a77d1a6c7b74359
@@ -455,9 +455,9 @@ F src/auth.c 0fac71038875693a937e506bceb492c5f136dd7b1249fbd4ae70b4e8da14f9df
 F src/backup.c 78d3cecfbe28230a3a9a1793e2ead609f469be43e8f486ca996006be551857ab
 F src/bitvec.c 17ea48eff8ba979f1f5b04cc484c7bb2be632f33
 F src/btmutex.c 8acc2f464ee76324bf13310df5692a262b801808984c1b79defb2503bbafadb6
-F src/btree.c c78051b514c5ea214f5ee1119d5df7d47471e32c0cb4d5b93f135bf86d67f0ca
+F src/btree.c 3378f2f410af2db1c4603fb085d71139811a7c86f8de8511da3acbae984c1cf4
 F src/btree.h febb2e817be499570b7a2e32a9bbb4b607a9234f6b84bb9ae84916d4806e96f2
-F src/btreeInt.h 620ab4c7235f43572cf3ac2ac8723cbdf68073be4d29da24897c7b77dda5fd96
+F src/btreeInt.h cd82f0f08886078bf99b29e1a7045960b1ca5d9d5829c38607e1299c508eaf00
 F src/build.c f07c0b154c23737d1699ee63bba31c8ca8b323e2446b957bc6bfec81a62295fc
 F src/callback.c 25dda5e1c2334a367b94a64077b1d06b2553369f616261ca6783c48bcb6bda73
 F src/complete.c a3634ab1e687055cd002e11b8f43eb75c17da23e
@@ -1804,7 +1804,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 9cf8ebd141aa2eb661d457624c76433bd9e4abfdef04aa52e28bc169172c2c8f
-R 3e3c6032378ec0b1bc4989b8470ba10d
+P 42687d45aa1a2b2a32ddfc5711b4ae9cf76b8cfbeb20b57d6705ecaf5824fcb6
+R 4d32b449c698c9011df8cf39a327380e
 U drh
-Z f362f232181a0d8f741744fba7a850da
+Z 17d57a5f847e0926de782c15e1422907

diff --git a/manifest.uuid b/manifest.uuid
index 133bde08bd7bb772cf2b4c2c2422eadebde7231b..a0bfbf310d30819c95602b7f250e013c84de8b88 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-42687d45aa1a2b2a32ddfc5711b4ae9cf76b8cfbeb20b57d6705ecaf5824fcb6
\ No newline at end of file
+6089d5dba73437d787259033e94a38cf1b0c87cac4a89c27e69d8239c22f496e
\ No newline at end of file

diff --git a/src/btree.c b/src/btree.c
index e0a9862b6fb2742c8374ce1225d7f579e0b61d14..244ed54f4e73ffd85d697e8410ef4a82ca4dd685 100644 (file)
--- a/src/btree.c
+++ b/src/btree.c
@@ -845,7 +845,7 @@ static int btreeRestoreCursorPosition(BtCursor *pCur){
     sqlite3_free(pCur->pKey);
     pCur->pKey = 0;
     assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
-    pCur->skipNext |= skipNext;
+    if( skipNext ) pCur->skipNext = skipNext;
     if( pCur->skipNext && pCur->eState==CURSOR_VALID ){
       pCur->eState = CURSOR_SKIPNEXT;
     }
@@ -915,7 +915,6 @@ int sqlite3BtreeCursorRestore(BtCursor *pCur, int *pDifferentRow){
   if( pCur->eState!=CURSOR_VALID ){
     *pDifferentRow = 1;
   }else{
-    assert( pCur->skipNext==0 );
     *pDifferentRow = 0;
   }
   return SQLITE_OK;
@@ -5334,7 +5333,7 @@ int sqlite3BtreeMovetoUnpacked(
       ** try to get there using sqlite3BtreeNext() rather than a full
       ** binary search.  This is an optimization only.  The correct answer
       ** is still obtained without this case, only a little more slowely */
-      if( pCur->info.nKey+1==intKey && !pCur->skipNext ){
+      if( pCur->info.nKey+1==intKey ){
         *pRes = 0;
         rc = sqlite3BtreeNext(pCur, 0);
         if( rc==SQLITE_OK ){
@@ -5608,7 +5607,6 @@ static SQLITE_NOINLINE int btreeNext(BtCursor *pCur){
   MemPage *pPage;
 
   assert( cursorOwnsBtShared(pCur) );
-  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
   if( pCur->eState!=CURSOR_VALID ){
     assert( (pCur->curFlags & BTCF_ValidOvfl)==0 );
     rc = restoreCursorPosition(pCur);
@@ -5618,14 +5616,9 @@ static SQLITE_NOINLINE int btreeNext(BtCursor *pCur){
     if( CURSOR_INVALID==pCur->eState ){
       return SQLITE_DONE;
     }
-    if( pCur->skipNext ){
-      assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_SKIPNEXT );
+    if( pCur->eState==CURSOR_SKIPNEXT ){
       pCur->eState = CURSOR_VALID;
-      if( pCur->skipNext>0 ){
-        pCur->skipNext = 0;
-        return SQLITE_OK;
-      }
-      pCur->skipNext = 0;
+      if( pCur->skipNext>0 ) return SQLITE_OK;
     }
   }
 
@@ -5680,7 +5673,6 @@ int sqlite3BtreeNext(BtCursor *pCur, int flags){
   UNUSED_PARAMETER( flags );  /* Used in COMDB2 but not native SQLite */
   assert( cursorOwnsBtShared(pCur) );
   assert( flags==0 || flags==1 );
-  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
   pCur->info.nSize = 0;
   pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
   if( pCur->eState!=CURSOR_VALID ) return btreeNext(pCur);
@@ -5721,7 +5713,6 @@ static SQLITE_NOINLINE int btreePrevious(BtCursor *pCur){
   MemPage *pPage;
 
   assert( cursorOwnsBtShared(pCur) );
-  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
   assert( (pCur->curFlags & (BTCF_AtLast|BTCF_ValidOvfl|BTCF_ValidNKey))==0 );
   assert( pCur->info.nSize==0 );
   if( pCur->eState!=CURSOR_VALID ){
@@ -5732,14 +5723,9 @@ static SQLITE_NOINLINE int btreePrevious(BtCursor *pCur){
     if( CURSOR_INVALID==pCur->eState ){
       return SQLITE_DONE;
     }
-    if( pCur->skipNext ){
-      assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_SKIPNEXT );
+    if( CURSOR_SKIPNEXT==pCur->eState ){
       pCur->eState = CURSOR_VALID;
-      if( pCur->skipNext<0 ){
-        pCur->skipNext = 0;
-        return SQLITE_OK;
-      }
-      pCur->skipNext = 0;
+      if( pCur->skipNext<0 ) return SQLITE_OK;
     }
   }
 
@@ -5774,7 +5760,6 @@ static SQLITE_NOINLINE int btreePrevious(BtCursor *pCur){
 int sqlite3BtreePrevious(BtCursor *pCur, int flags){
   assert( cursorOwnsBtShared(pCur) );
   assert( flags==0 || flags==1 );
-  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
   UNUSED_PARAMETER( flags );  /* Used in COMDB2 but not native SQLite */
   pCur->curFlags &= ~(BTCF_AtLast|BTCF_ValidOvfl|BTCF_ValidNKey);
   pCur->info.nSize = 0;
@@ -8770,7 +8755,6 @@ int sqlite3BtreeDelete(BtCursor *pCur, u8 flags){
   ** sub-tree headed by the child page of the cell being deleted. This makes
   ** balancing the tree following the delete operation easier.  */
   if( !pPage->leaf ){
-    pCur->skipNext = 0;
     rc = sqlite3BtreePrevious(pCur, 0);
     assert( rc!=SQLITE_DONE );
     if( rc ) return rc;

diff --git a/src/btreeInt.h b/src/btreeInt.h
index d1e2c08d18f46fd639da1607631b69dec9384dff..ea5e0815a16f16dc820c226d6d35705bad604b5d 100644 (file)
--- a/src/btreeInt.h
+++ b/src/btreeInt.h
@@ -494,9 +494,16 @@ struct CellInfo {
 ** found at self->pBt->mutex. 
 **
 ** skipNext meaning:
-**    eState==SKIPNEXT && skipNext>0:  Next sqlite3BtreeNext() is no-op.
-**    eState==SKIPNEXT && skipNext<0:  Next sqlite3BtreePrevious() is no-op.
-**    eState==FAULT:                   Cursor fault with skipNext as error code.
+** The meaning of skipNext depends on the value of eState:
+**
+**   eState            Meaning of skipNext
+**   VALID             skipNext is meaningless and is ignored
+**   INVALID           skipNext is meaningless and is ignored
+**   SKIPNEXT          sqlite3BtreeNext() is a no-op if skipNext>0 and
+**                     sqlite3BtreePrevious() is no-op if skipNext<0.
+**   REQUIRESEEK       restoreCursorPosition() restores the cursor to
+**                     eState=SKIPNEXT if skipNext!=0
+**   FAULT             skipNext holds the cursor fault error code.
 */
 struct BtCursor {
   u8 eState;                /* One of the CURSOR_XXX constants (see below) */