[sql] Import SQLite 3.17.0.

third_party/sqlite/src/src/backup.c

 /*
 ** 2009 January 28
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
 **
 **    May you do good and not evil.
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
@@ skipping 65 matching lines @@
 ** a NULL pointer and write an error message to pErrorDb.
 **
 ** If the "temp" database is requested, it may need to be opened by this 
 ** function. If an error occurs while doing so, return 0 and write an 
 ** error message to pErrorDb.
 */
 static Btree *findBtree(sqlite3 *pErrorDb, sqlite3 *pDb, const char *zDb){
   int i = sqlite3FindDbName(pDb, zDb);
 
   if( i==1 ){
-    Parse *pParse;
+    Parse sParse;
     int rc = 0;
-    pParse = sqlite3StackAllocZero(pErrorDb, sizeof(*pParse));
-    if( pParse==0 ){
-      sqlite3ErrorWithMsg(pErrorDb, SQLITE_NOMEM, "out of memory");
-      rc = SQLITE_NOMEM;
-    }else{
-      pParse->db = pDb;
-      if( sqlite3OpenTempDatabase(pParse) ){
-        sqlite3ErrorWithMsg(pErrorDb, pParse->rc, "%s", pParse->zErrMsg);
-        rc = SQLITE_ERROR;
-      }
-      sqlite3DbFree(pErrorDb, pParse->zErrMsg);
-      sqlite3ParserReset(pParse);
-      sqlite3StackFree(pErrorDb, pParse);
+    memset(&sParse, 0, sizeof(sParse));
+    sParse.db = pDb;
+    if( sqlite3OpenTempDatabase(&sParse) ){
+      sqlite3ErrorWithMsg(pErrorDb, sParse.rc, "%s", sParse.zErrMsg);
+      rc = SQLITE_ERROR;
     }
+    sqlite3DbFree(pErrorDb, sParse.zErrMsg);
+    sqlite3ParserReset(&sParse);
     if( rc ){
       return 0;
     }
   }
 
   if( i<0 ){
     sqlite3ErrorWithMsg(pErrorDb, SQLITE_ERROR, "unknown database %s", zDb);
     return 0;
   }
 
@@ skipping 63 matching lines @@
         pDestDb, SQLITE_ERROR, "source and destination must be distinct"
     );
     p = 0;
   }else {
     /* Allocate space for a new sqlite3_backup object...
     ** EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
     ** call to sqlite3_backup_init() and is destroyed by a call to
     ** sqlite3_backup_finish(). */
     p = (sqlite3_backup *)sqlite3MallocZero(sizeof(sqlite3_backup));
     if( !p ){
-      sqlite3Error(pDestDb, SQLITE_NOMEM);
+      sqlite3Error(pDestDb, SQLITE_NOMEM_BKPT);
     }
   }
 
   /* If the allocation succeeded, populate the new object. */
   if( p ){
     p->pSrc = findBtree(pDestDb, pSrcDb, zSrcDb);
     p->pDest = findBtree(pDestDb, pDestDb, zDestDb);
     p->pDestDb = pDestDb;
     p->pSrcDb = pSrcDb;
     p->iNext = 1;
     p->isAttached = 0;
 
     if( 0==p->pSrc || 0==p->pDest 
-     || setDestPgsz(p)==SQLITE_NOMEM 
      || checkReadTransaction(pDestDb, p->pDest)!=SQLITE_OK 
      ){
       /* One (or both) of the named databases did not exist or an OOM
       ** error was hit. Or there is a transaction open on the destination
       ** database. The error has already been written into the pDestDb 
       ** handle. All that is left to do here is free the sqlite3_backup 
       ** structure.  */
       sqlite3_free(p);
       p = 0;
     }
@@ skipping 167 matching lines @@
 
     /* If the source pager is currently in a write-transaction, return
     ** SQLITE_BUSY immediately.
     */
     if( p->pDestDb && p->pSrc->pBt->inTransaction==TRANS_WRITE ){
       rc = SQLITE_BUSY;
     }else{
       rc = SQLITE_OK;
     }
 
-    /* Lock the destination database, if it is not locked already. */
-    if( SQLITE_OK==rc && p->bDestLocked==0
-     && SQLITE_OK==(rc = sqlite3BtreeBeginTrans(p->pDest, 2)) 
-    ){
-      p->bDestLocked = 1;
-      sqlite3BtreeGetMeta(p->pDest, BTREE_SCHEMA_VERSION, &p->iDestSchema);
-    }
-
     /* If there is no open read-transaction on the source database, open
     ** one now. If a transaction is opened here, then it will be closed
     ** before this function exits.
     */
     if( rc==SQLITE_OK && 0==sqlite3BtreeIsInReadTrans(p->pSrc) ){
       rc = sqlite3BtreeBeginTrans(p->pSrc, 0);
       bCloseTrans = 1;
     }
 
+    /* If the destination database has not yet been locked (i.e. if this
+    ** is the first call to backup_step() for the current backup operation),
+    ** try to set its page size to the same as the source database. This
+    ** is especially important on ZipVFS systems, as in that case it is
+    ** not possible to create a database file that uses one page size by
+    ** writing to it with another.  */
+    if( p->bDestLocked==0 && rc==SQLITE_OK && setDestPgsz(p)==SQLITE_NOMEM ){
+      rc = SQLITE_NOMEM;
+    }
+
+    /* Lock the destination database, if it is not locked already. */
+    if( SQLITE_OK==rc && p->bDestLocked==0
+     && SQLITE_OK==(rc = sqlite3BtreeBeginTrans(p->pDest, 2)) 
+    ){
+      p->bDestLocked = 1;
+      sqlite3BtreeGetMeta(p->pDest, BTREE_SCHEMA_VERSION, &p->iDestSchema);
+    }
+
     /* Do not allow backup if the destination database is in WAL mode
     ** and the page sizes are different between source and destination */
     pgszSrc = sqlite3BtreeGetPageSize(p->pSrc);
     pgszDest = sqlite3BtreeGetPageSize(p->pDest);
     destMode = sqlite3PagerGetJournalMode(sqlite3BtreePager(p->pDest));
     if( SQLITE_OK==rc && destMode==PAGER_JOURNALMODE_WAL && pgszSrc!=pgszDest ){
       rc = SQLITE_READONLY;
     }
   
     /* Now that there is a read-lock on the source database, query the
@@ skipping 160 matching lines @@
     ** "committing" a read-only transaction cannot fail.
     */
     if( bCloseTrans ){
       TESTONLY( int rc2 );
       TESTONLY( rc2  = ) sqlite3BtreeCommitPhaseOne(p->pSrc, 0);
       TESTONLY( rc2 |= ) sqlite3BtreeCommitPhaseTwo(p->pSrc, 0);
       assert( rc2==SQLITE_OK );
     }
   
     if( rc==SQLITE_IOERR_NOMEM ){
-      rc = SQLITE_NOMEM;
+      rc = SQLITE_NOMEM_BKPT;
     }
     p->rc = rc;
   }
   if( p->pDestDb ){
     sqlite3_mutex_leave(p->pDestDb->mutex);
   }
   sqlite3BtreeLeave(p->pSrc);
   sqlite3_mutex_leave(p->pSrcDb->mutex);
   return rc;
 }
@@ skipping 175 matching lines @@
 
 #ifdef SQLITE_HAS_CODEC
   sqlite3PagerAlignReserve(sqlite3BtreePager(pTo), sqlite3BtreePager(pFrom));
 #endif
 
   /* 0x7FFFFFFF is the hard limit for the number of pages in a database
   ** file. By passing this as the number of pages to copy to
   ** sqlite3_backup_step(), we can guarantee that the copy finishes 
   ** within a single call (unless an error occurs). The assert() statement
   ** checks this assumption - (p->rc) should be set to either SQLITE_DONE 
-  ** or an error code.
-  */
+  ** or an error code.  */
   sqlite3_backup_step(&b, 0x7FFFFFFF);
   assert( b.rc!=SQLITE_OK );
+
   rc = sqlite3_backup_finish(&b);
   if( rc==SQLITE_OK ){
     pTo->pBt->btsFlags &= ~BTS_PAGESIZE_FIXED;
   }else{
     sqlite3PagerClearCache(sqlite3BtreePager(b.pDest));
   }
 
   assert( sqlite3BtreeIsInTrans(pTo)==0 );
 copy_finished:
   sqlite3BtreeLeave(pFrom);
   sqlite3BtreeLeave(pTo);
   return rc;
 }
 #endif /* SQLITE_OMIT_VACUUM */