From: dan <dan@noemail.net>
Date: Fri, 26 Apr 2019 15:14:53 +0000 (+0000)
Subject: Fix a locking-page related problem with the ".recover" command.
X-Git-Tag: version-3.29.0~176^2~6
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c0b42437ab69d01daa61bd77f74badb95c82bd40;p=thirdparty%2Fsqlite.git

Fix a locking-page related problem with the ".recover" command.

FossilOrigin-Name: afdae10424f0f3d0f10a4b73e9732aa55c5ee664814d8ca0edd372cfb17c2445
---

diff --git a/ext/misc/dbdata.c b/ext/misc/dbdata.c
index 13bb51f08b..a27f19dc7a 100644
--- a/ext/misc/dbdata.c
+++ b/ext/misc/dbdata.c
@@ -89,6 +89,7 @@ struct DbdataCursor {
   int nCell;                      /* Number of cells on aPage[] */
   int iCell;                      /* Current cell number */
   int bOnePage;                   /* True to stop after one page */
+  int szDb;
   sqlite3_int64 iRowid;
 
   /* Only for the sqlite_dbdata table */
@@ -303,18 +304,21 @@ static int dbdataLoadPage(
   sqlite3_bind_int64(pStmt, 2, pgno);
   if( SQLITE_ROW==sqlite3_step(pStmt) ){
     int nCopy = sqlite3_column_bytes(pStmt, 0);
-    u8 *pPage = (u8*)sqlite3_malloc64(nCopy);
-    if( pPage==0 ){
-      rc = SQLITE_NOMEM;
-    }else{
-      const u8 *pCopy = sqlite3_column_blob(pStmt, 0);
-      memcpy(pPage, pCopy, nCopy);
+    if( nCopy>0 ){
+      u8 *pPage;
+      pPage = (u8*)sqlite3_malloc64(nCopy);
+      if( pPage==0 ){
+        rc = SQLITE_NOMEM;
+      }else{
+        const u8 *pCopy = sqlite3_column_blob(pStmt, 0);
+        memcpy(pPage, pCopy, nCopy);
+      }
       *ppPage = pPage;
       *pnPage = nCopy;
     }
   }
   rc2 = sqlite3_reset(pStmt);
-  if( *ppPage==0 ) rc = rc2;
+  if( rc==SQLITE_OK ) rc = rc2;
 
   return rc;
 }
@@ -419,8 +423,13 @@ static int dbdataNext(sqlite3_vtab_cursor *pCursor){
     int iOff = (pCsr->iPgno==1 ? 100 : 0);
 
     if( pCsr->aPage==0 ){
-      rc = dbdataLoadPage(pCsr, pCsr->iPgno, &pCsr->aPage, &pCsr->nPage);
-      if( rc!=SQLITE_OK || pCsr->aPage==0 ) return rc;
+      while( 1 ){
+        if( pCsr->bOnePage==0 && pCsr->iPgno>pCsr->szDb ) return SQLITE_OK;
+        rc = dbdataLoadPage(pCsr, pCsr->iPgno, &pCsr->aPage, &pCsr->nPage);
+        if( rc!=SQLITE_OK ) return rc;
+        if( pCsr->aPage ) break;
+        pCsr->iPgno++;
+      }
       pCsr->iCell = pTab->bPtr ? -2 : 0;
       pCsr->nCell = get_uint16(&pCsr->aPage[iOff+3]);
     }
@@ -574,6 +583,24 @@ static int dbdataEof(sqlite3_vtab_cursor *pCursor){
   return pCsr->aPage==0;
 }
 
+static int dbdataDbsize(DbdataCursor *pCsr, const char *zSchema){
+  DbdataTable *pTab = (DbdataTable*)pCsr->base.pVtab;
+  char *zSql = 0;
+  int rc, rc2;
+  sqlite3_stmt *pStmt = 0;
+
+  zSql = sqlite3_mprintf("PRAGMA %Q.page_count", zSchema);
+  if( zSql==0 ) return SQLITE_NOMEM;
+  rc = sqlite3_prepare_v2(pTab->db, zSql, -1, &pStmt, 0);
+  sqlite3_free(zSql);
+  if( rc==SQLITE_OK && sqlite3_step(pStmt)==SQLITE_ROW ){
+    pCsr->szDb = sqlite3_column_int(pStmt, 0);
+  }
+  rc2 = sqlite3_finalize(pStmt);
+  if( rc==SQLITE_OK ) rc = rc2;
+  return rc;
+}
+
 /* Position a cursor back to the beginning.
 */
 static int dbdataFilter(
@@ -594,16 +621,21 @@ static int dbdataFilter(
   if( idxNum & 0x02 ){
     pCsr->iPgno = sqlite3_value_int(argv[(idxNum & 0x01)]);
     pCsr->bOnePage = 1;
+  }else{
+    pCsr->nPage = dbdataDbsize(pCsr, zSchema);
+    rc = dbdataDbsize(pCsr, zSchema);
   }
 
-  if( pTab->pStmt ){
-    pCsr->pStmt = pTab->pStmt;
-    pTab->pStmt = 0;
-  }else{
-    rc = sqlite3_prepare_v2(pTab->db, 
-        "SELECT data FROM sqlite_dbpage(?) WHERE pgno=?", -1,
-        &pCsr->pStmt, 0
-    );
+  if( rc==SQLITE_OK ){
+    if( pTab->pStmt ){
+      pCsr->pStmt = pTab->pStmt;
+      pTab->pStmt = 0;
+    }else{
+      rc = sqlite3_prepare_v2(pTab->db, 
+          "SELECT data FROM sqlite_dbpage(?) WHERE pgno=?", -1,
+          &pCsr->pStmt, 0
+      );
+    }
   }
   if( rc==SQLITE_OK ){
     rc = sqlite3_bind_text(pCsr->pStmt, 1, zSchema, -1, SQLITE_TRANSIENT);
diff --git a/manifest b/manifest
index c6b5a05076..d361dc7ebc 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Merge\slatest\strunk\schanges\sinto\sthis\sbranch.
-D 2019-04-25T20:06:34.069
+C Fix\sa\slocking-page\srelated\sproblem\swith\sthe\s".recover"\scommand.
+D 2019-04-26T15:14:53.514
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -284,7 +284,7 @@ F ext/misc/closure.c dbfd8543b2a017ae6b1a5843986b22ddf99ff126ec9634a2f4047cd14c8
 F ext/misc/completion.c cec672d40604075bb341a7f11ac48393efdcd90a979269b8fe7977ea62d0547f
 F ext/misc/compress.c dd4f8a6d0baccff3c694757db5b430f3bbd821d8686d1fc24df55cf9f035b189
 F ext/misc/csv.c 7f047aeb68f5802e7ce6639292095d622a488bb43526ed04810e0649faa71ceb
-F ext/misc/dbdata.c 0c80f0757c3a1b5c57027328ab0ccfe30fcef1a4875b41dd9ddc0f53c7087e97
+F ext/misc/dbdata.c b7547f43906f9296e43be807ca78e2ef3f335ca26d6e91d178df30cd2fd46572
 F ext/misc/dbdump.c baf6e37447c9d6968417b1cd34cbedb0b0ab3f91b5329501d8a8d5be3287c336
 F ext/misc/eval.c 4b4757592d00fd32e44c7a067e6a0e4839c81a4d57abc4131ee7806d1be3104e
 F ext/misc/explain.c d5c12962d79913ef774b297006872af1fccda388f61a11d37758f9179a09551f
@@ -520,7 +520,7 @@ F src/random.c 80f5d666f23feb3e6665a6ce04c7197212a88384
 F src/resolve.c 567888ee3faec14dae06519b4306201771058364a37560186a3e0e755ebc4cb8
 F src/rowset.c d977b011993aaea002cab3e0bb2ce50cf346000dff94e944d547b989f4b1fe93
 F src/select.c b7304d2f491c11a03a7fbdf34bc218282ac54052377809d4dc3b4b1e7f4bfc93
-F src/shell.c.in 78004b100ed486695f4ff8bbc40b99c2e4d7b6d06278ce64b80ac1900bf356a3
+F src/shell.c.in 63b1075817997806d7f09c2a0433ffac854b6dee47836ef938d51531cdb8042f
 F src/sqlite.h.in 38390767acc1914d58930e03149595ee4710afa4e3c43ab6c3a8aea3f1a6b8cd
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 9ecc93b8493bd20c0c07d52e2ac0ed8bab9b549c7f7955b59869597b650dd8b5
@@ -1821,7 +1821,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 8d2f52bb640d6d0f84b18d746043e56f45a73ace93239be1d036701f7f4018fd 7be6222c9ec44596e4eddd906c831eb1272b90fbdf68641d791f216264feb7cf
-R af342ccd780cc18bf46aaaf7890063fa
+P 1da302d85d7ad4ba54f877117a45d667439fd2ef31dc70ea1d54dc1fba196e68
+R 981714fd52a70e51cf4586f924a49fdc
 U dan
-Z 147b326af09d7b23ccf3f83204577057
+Z 303a0ea3c8fcc86a61370f3e12d83ec5
diff --git a/manifest.uuid b/manifest.uuid
index 0d49487589..b5f67ee780 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-1da302d85d7ad4ba54f877117a45d667439fd2ef31dc70ea1d54dc1fba196e68
\ No newline at end of file
+afdae10424f0f3d0f10a4b73e9732aa55c5ee664814d8ca0edd372cfb17c2445
\ No newline at end of file
diff --git a/src/shell.c.in b/src/shell.c.in
index 55f7964319..1884e7bfe2 100644
--- a/src/shell.c.in
+++ b/src/shell.c.in
@@ -6165,6 +6165,22 @@ static void shellExec(sqlite3 *db, int *pRc, const char *zSql){
   }
 }
 
+static void shellExecPrintf(sqlite3 *db, int *pRc, const char *zFmt, ...){
+  char *z = 0;
+  if( *pRc==SQLITE_OK ){
+    va_list ap;
+    va_start(ap, zFmt);
+    z = sqlite3_vmprintf(zFmt, ap);
+    va_end(ap);
+    if( z==0 ){
+      *pRc = SQLITE_NOMEM;
+    }else{
+      shellExec(db, pRc, z);
+    }
+    sqlite3_free(z);
+  }
+}
+
 static void *shellMalloc(int *pRc, sqlite3_int64 nByte){
   void *pRet = 0;
   if( *pRc==SQLITE_OK ){
@@ -6405,6 +6421,7 @@ static int recoverDatabaseCmd(ShellState *pState, int nArg, char **azArg){
   sqlite3_stmt *pLoop = 0;        /* Loop through all root pages */
   sqlite3_stmt *pPages = 0;       /* Loop through all pages in a group */
   sqlite3_stmt *pCells = 0;       /* Loop through all cells in a page */
+  const char *zRecoveryDb = "";   /* Name of "recovery" database */
   int i;
 
   int bFreelist = 1;              /* 0 if --freelist-corrupt is specified */
@@ -6416,23 +6433,32 @@ static int recoverDatabaseCmd(ShellState *pState, int nArg, char **azArg){
     if( n<=17 && memcmp("-freelist-corrupt", z, n)==0 ){
       bFreelist = 0;
     }
+    if( n<=12 && memcmp("-recovery-db", z, n)==0 && i<(nArg-1) ){
+      i++;
+      zRecoveryDb = azArg[i];
+    }
     else{
-      raw_printf(stderr, 
-        "unexpected option: %s - expected \"--freelist-corrupt\"\n", 
-        azArg[i]
-      );
+      raw_printf(stderr, "unexpected option: %s\n", azArg[i]); 
+      raw_printf(stderr, "options are:\n");
+      raw_printf(stderr, "    --freelist-corrupt\n");
+      raw_printf(stderr, "    --recovery-db DATABASE\n");
       return 1;
     }
   }
 
-  shellExec(pState->db, &rc, 
+  shellExecPrintf(pState->db, &rc,
     /* Attach an in-memory database named 'recovery'. Create an indexed 
     ** cache of the sqlite_dbptr virtual table. */
-    "ATTACH '' AS recovery;"
+    "ATTACH %Q AS recovery;"
+    "DROP TABLE IF EXISTS recovery.dbptr;"
+    "DROP TABLE IF EXISTS recovery.freelist;"
+    "DROP TABLE IF EXISTS recovery.map;"
+    "DROP TABLE IF EXISTS recovery.schema;"
     "CREATE TABLE recovery.dbptr("
     "      pgno, child, PRIMARY KEY(child, pgno)"
     ") WITHOUT ROWID;"
-    "INSERT OR IGNORE INTO dbptr(pgno, child) SELECT * FROM sqlite_dbptr;"
+    "INSERT OR IGNORE INTO recovery.dbptr(pgno, child) "
+    "    SELECT * FROM sqlite_dbptr;"
 
     /* Delete any pointer to page 1. This ensures that page 1 is considered
     ** a root page, regardless of how corrupt the db is. */
@@ -6445,7 +6471,7 @@ static int recoverDatabaseCmd(ShellState *pState, int nArg, char **azArg){
     "  SELECT child FROM recovery.dbptr GROUP BY child HAVING count(*)>1"
     ");"
 
-    "CREATE TABLE recovery.freelist(pgno INTEGER PRIMARY KEY);"
+    "CREATE TABLE recovery.freelist(pgno INTEGER PRIMARY KEY);", zRecoveryDb
   );
 
   if( bFreelist ){