Block on the WRITER lock when attempting to run recovery.

FossilOrigin-Name: 105d6c9bbcadc64faa2b24e315cb13227b17cfc6bf1b3512713f80ce56976a3d

manifest

@@ -1,5 +1,5 @@
-C Add\stests\sfor\srunning\srecovery\swhen\sopening\sa\swrite\stransaction\sor\sperforming\sa\scheckpoint\swith\sblocking\slocks\senabled.\sFix\ssome\sfailing\sassert()\sstatements.
+C Block\son\sthe\sWRITER\slock\swhen\sattempting\sto\srun\srecovery.
-D 2020-05-06T17:18:57.298
+D 2020-05-06T19:14:41.236
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -474,7 +474,7 @@ F src/auth.c a3d5bfdba83d25abed1013a8c7a5f204e2e29b0c25242a56bc02bb0c07bf1e06
 F src/backup.c 5e617c087f1c2d6005c2ec694ce80d6e16bc68d906e1b1c556d7c7c2228b636b
 F src/bitvec.c 17ea48eff8ba979f1f5b04cc484c7bb2be632f33
 F src/btmutex.c 8acc2f464ee76324bf13310df5692a262b801808984c1b79defb2503bbafadb6
-F src/btree.c e810b07f2212f36c1f317b94bd9af818be4a0aec24e935c11c39470dcd77c149
+F src/btree.c 4d5a7d2208dd8d921049780c9f06201cd6a656822c4f0931807b54f3dcd79097
 F src/btree.h 989ef3c33413549e3e148f3dcb46c030f317dac130dc86809ba6b9aa4b16c72a
 F src/btreeInt.h 887cdd2ea7f4a65143074a8a7c8928b0546f8c18dda3c06a408ce7992cbab0c0
 F src/build.c ec6c0bda1e43ef55e5f5121a77ba19fac51fc6585f95ce2da795bcedcf6e8f36
@@ -497,7 +497,7 @@ F src/in-operator.md 10cd8f4bcd225a32518407c2fb2484089112fd71
 F src/insert.c 8e4211d04eb460c0694d486c6ba1c068d468c6f653c3f237869a802ad82854de
 F src/legacy.c d7874bc885906868cd51e6c2156698f2754f02d9eee1bae2d687323c3ca8e5aa
 F src/loadext.c 421310045bd78afefb772294a99e50f37d87ae578786a6169074e6291e30d969
-F src/main.c 5ae818ae552d3f68d1e67707a200d557125cdfb4f9e14e5cf1b4f12181974934
+F src/main.c 685d391fc37ad2c1162ad6784cae4a454dcd3632bbab319464af733d71eca72f
 F src/malloc.c a3e13b001f988ecec6bdb90c0ea8912c8c786e623724d7098da623d8d01d19b1
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
 F src/mem1.c c12a42539b1ba105e3707d0e628ad70e611040d8f5e38cf942cee30c867083de
@@ -520,8 +520,8 @@ F src/os_setup.h 0dbaea40a7d36bf311613d31342e0b99e2536586
 F src/os_unix.c 0e1acfbb8a75f2a4acede6078b072238df63981b172a9cd16f8b090d68291c15
 F src/os_win.c 035a813cbd17f355bdcad7ab894af214a9c13a1db8aeac902365350b98cd45a7
 F src/os_win.h 7b073010f1451abe501be30d12f6bc599824944a
-F src/pager.c be4d6d58df5c5d02b84547fd253a80f035ea2ee53931a5393d96af0ba3f04edb
+F src/pager.c 96436cb1920074d4ade120a1a8a9d0ae3f52df06651e21b7eccc5eae2f02b111
-F src/pager.h 5e2c0e5bd32aa4ae6c25eda2722490bb3f671f24d2e5d665d33df13285c1d520
+F src/pager.h 8d1dc9a2c3fc5eb6eeed75f48a076f425e77706f8935f05817fa05a308f587b5
 F src/parse.y c8eff38606f443d5ba245263fa7abc05e4116d95656e050c4b78e9bfbf931add
 F src/pcache.c 385ff064bca69789d199a98e2169445dc16e4291fa807babd61d4890c3b34177
 F src/pcache.h 4f87acd914cef5016fae3030343540d75f5b85a1877eed1a2a19b9f284248586
@@ -617,8 +617,8 @@ F src/vdbetrace.c fa3bf238002f0bbbdfb66cc8afb0cea284ff9f148d6439bc1f6f2b4c3b7143
 F src/vdbevtab.c 8094dfc28dad82d60a1c832020a1b201a5381dc185c14638affc6d4e9d54c653
 F src/vtab.c 7b704a90515a239c6cdba6a66b1bb3a385e62326cceb5ecb05ec7a091d6b8515
 F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
-F src/wal.c 9cf3f288cd4e48b49725e03037b60246a154ca8775892c75c319db8f5652ae8a
+F src/wal.c d23410a4330d11b8c699e0e463f334f2fca6c5af2c144e34674ccaef5b73f8fc
-F src/wal.h 484890eaaefb89c0f2043ae34c20bf367383f201f63da631ecae424797a7f60d
+F src/wal.h c3aa7825bfa2fe0d85bef2db94655f99870a285778baa36307c0a16da32b226a
 F src/walker.c 7c429c694abd12413a5c17aec9f47cfe9eba6807e6b0a32df883e8e3a14835ed
 F src/where.c 9546c82056e8cdb27291f98cf1adca5d271240b399bb97b32f77fc2bea6146c9
 F src/whereInt.h 6b874aa15f94e43a2cec1080be64d955b04deeafeac90ffb5d6975c0d511be3c
@@ -1864,7 +1864,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P a3727dba10b476f414f0a049b35f2a5c169a408eccefa6833821560684e07f8b
+P d096ea3fe20f8af90f9e3f798fd0a69527b32ac8e208ade58b9d0af0e831f41b
-R e1d7b36a881e7c026e918bb1e2d9268d
+R 452bcfebade640ff986656d7117060f0
 U dan
-Z 92e7a8a964d43aa5533a6dd765b70a70
+Z 21f20f1df91440f33362da9da7770293

manifest.uuid

@@ -1 +1 @@
-d096ea3fe20f8af90f9e3f798fd0a69527b32ac8e208ade58b9d0af0e831f41b
+105d6c9bbcadc64faa2b24e315cb13227b17cfc6bf1b3512713f80ce56976a3d

src/btree.c

@@ -3442,9 +3442,10 @@ int sqlite3BtreeBeginTrans(Btree *p, int wrflag, int *pSchemaVersion){
 #ifdef SQLITE_ENABLE_SETLK_TIMEOUT
     /* If transitioning from no transaction directly to a write transaction,
     ** block for the WRITER lock first if possible. */
+    sqlite3PagerWalDb(pPager, p->db);
     if( pBt->pPage1==0 && wrflag ){
       assert( pBt->inTransaction==TRANS_NONE );
-      rc = sqlite3PagerWalWriteLock(p->db, pPager, 1);
+      rc = sqlite3PagerWalWriteLock(pPager, 1);
       if( rc!=SQLITE_OK ) break;
     }
 #endif
@@ -3475,9 +3476,10 @@ int sqlite3BtreeBeginTrans(Btree *p, int wrflag, int *pSchemaVersion){
     }
   
     if( rc!=SQLITE_OK ){
-      sqlite3PagerWalWriteLock(p->db, pPager, 0);
+      sqlite3PagerWalWriteLock(pPager, 0);
       unlockBtreeIfUnused(pBt);
     }
+    sqlite3PagerWalDb(pPager, 0);
   }while( (rc&0xFF)==SQLITE_BUSY && pBt->inTransaction==TRANS_NONE &&
           btreeInvokeBusyHandler(pBt) );
 

src/main.c

@@ -4481,11 +4481,11 @@ int sqlite3_snapshot_open(
           rc = SQLITE_OK;
         }
         if( rc==SQLITE_OK ){
-          rc = sqlite3PagerSnapshotOpen(pPager, db, pSnapshot);
+          rc = sqlite3PagerSnapshotOpen(pPager, pSnapshot);
         }
         if( rc==SQLITE_OK ){
           rc = sqlite3BtreeBeginTrans(pBt, 0, 0);
-          sqlite3PagerSnapshotOpen(pPager, 0, 0);
+          sqlite3PagerSnapshotOpen(pPager, 0);
         }
         if( bUnlock ){
           sqlite3PagerSnapshotUnlock(pPager);

src/pager.c

@@ -7581,13 +7581,23 @@ int sqlite3PagerCloseWal(Pager *pPager, sqlite3 *db){
 ** with the same db and bLock parameters as were passed to this function.
 ** Return an SQLite error code if an error occurs, or SQLITE_OK otherwise.
 */
-int sqlite3PagerWalWriteLock(sqlite3 *db, Pager *pPager, int bLock){
+int sqlite3PagerWalWriteLock(Pager *pPager, int bLock){
   int rc = SQLITE_OK;
   if( pagerUseWal(pPager) && pPager->exclusiveMode==0 ){
-    rc = sqlite3WalWriteLock(db, pPager->pWal, bLock);
+    rc = sqlite3WalWriteLock(pPager->pWal, bLock);
   }
   return rc;
 }
+
+/*
+** Set the database handle used by the wal layer to determine if 
+** blocking locks are required.
+*/
+void sqlite3PagerWalDb(Pager *pPager, sqlite3 *db){
+  if( pagerUseWal(pPager) ){
+    sqlite3WalDb(pPager->pWal, db);
+  }
+}
 #endif
 
 #ifdef SQLITE_ENABLE_SNAPSHOT
@@ -7610,12 +7620,11 @@ int sqlite3PagerSnapshotGet(Pager *pPager, sqlite3_snapshot **ppSnapshot){
 */
 int sqlite3PagerSnapshotOpen(
   Pager *pPager, 
-  sqlite3 *db, 
   sqlite3_snapshot *pSnapshot
 ){
   int rc = SQLITE_OK;
   if( pPager->pWal ){
-    sqlite3WalSnapshotOpen(pPager->pWal, db, pSnapshot);
+    sqlite3WalSnapshotOpen(pPager->pWal, pSnapshot);
   }else{
     rc = SQLITE_ERROR;
   }

src/pager.h

@@ -178,7 +178,7 @@ int sqlite3PagerSharedLock(Pager *pPager);
   int sqlite3PagerCloseWal(Pager *pPager, sqlite3*);
 # ifdef SQLITE_ENABLE_SNAPSHOT
   int sqlite3PagerSnapshotGet(Pager*, sqlite3_snapshot **ppSnapshot);
-  int sqlite3PagerSnapshotOpen(Pager*, sqlite3*, sqlite3_snapshot *pSnapshot);
+  int sqlite3PagerSnapshotOpen(Pager*, sqlite3_snapshot *pSnapshot);
   int sqlite3PagerSnapshotRecover(Pager *pPager);
   int sqlite3PagerSnapshotCheck(Pager *pPager, sqlite3_snapshot *pSnapshot);
   void sqlite3PagerSnapshotUnlock(Pager *pPager);
@@ -186,9 +186,11 @@ int sqlite3PagerSharedLock(Pager *pPager);
 #endif
 
 #if !defined(SQLITE_OMIT_WAL) && defined(SQLITE_ENABLE_SETLK_TIMEOUT)
-  int sqlite3PagerWalWriteLock(sqlite3*, Pager*, int);
+  int sqlite3PagerWalWriteLock(Pager*, int);
+  void sqlite3PagerWalDb(Pager*, sqlite3*);
 #else
-# define sqlite3PagerWalWriteLock(x,y,z) SQLITE_OK
+# define sqlite3PagerWalWriteLock(y,z) SQLITE_OK
+# define sqlite3PagerWalDb(x,y)
 #endif
 
 #ifdef SQLITE_DIRECT_OVERFLOW_READ

src/wal.c

@@ -466,9 +466,9 @@ struct Wal {
 #endif
 #ifdef SQLITE_ENABLE_SNAPSHOT
   WalIndexHdr *pSnapshot;    /* Start transaction here if not NULL */
-# ifdef SQLITE_ENABLE_SETLK_TIMEOUT
+#endif
-  sqlite3 *dbSnapshot;
+#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
-# endif
+  sqlite3 *db;
 #endif
 };
 
@@ -2118,6 +2118,88 @@ static int walIndexTryHdr(Wal *pWal, int *pChanged){
 */
 #define WAL_RETRY  (-1)
 
+#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
+/*
+** Attempt to enable blocking locks. Blocking locks are enabled only if (a)
+** they are supported by the VFS, and (b) the database handle is configured 
+** with a busy-timeout. Return 1 if blocking locks are successfully enabled, 
+** or 0 otherwise.
+*/
+static int walEnableBlocking(Wal *pWal){
+  int res = 0;
+  if( pWal->db ){
+    int tmout = pWal->db->busyTimeout;
+    if( tmout ){
+      int rc;
+      rc = sqlite3OsFileControl(
+          pWal->pDbFd, SQLITE_FCNTL_LOCK_TIMEOUT, (void*)&tmout
+          );
+      res = (rc==SQLITE_OK);
+    }
+  }
+  return res;
+}
+
+/*
+** Disable blocking locks.
+*/
+static void walDisableBlocking(Wal *pWal){
+  int tmout = 0;
+  sqlite3OsFileControl(pWal->pDbFd, SQLITE_FCNTL_LOCK_TIMEOUT, (void*)&tmout);
+}
+
+/*
+** If parameter bLock is true, attempt to enable blocking locks, take
+** the WRITER lock, and then disable blocking locks. If blocking locks
+** cannot be enabled, no attempt to obtain the WRITER lock is made. Return 
+** an SQLite error code if an error occurs, or SQLITE_OK otherwise. It is not
+** an error if blocking locks can not be enabled.
+**
+** If the bLock parameter is false and the WRITER lock is held, release it.
+*/
+int sqlite3WalWriteLock(Wal *pWal, int bLock){
+  int rc = SQLITE_OK;
+  assert( pWal->readLock<0 || bLock==0 );
+  if( bLock ){
+    assert( pWal->db );
+    if( walEnableBlocking(pWal) ){
+      rc = walLockExclusive(pWal, WAL_WRITE_LOCK, 1);
+      if( rc==SQLITE_OK ){
+        pWal->writeLock = 1;
+      }
+      walDisableBlocking(pWal);
+    }
+  }else if( pWal->writeLock ){
+    walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1);
+    pWal->writeLock = 0;
+  }
+  return rc;
+}
+
+/*
+** Set the database handle used to determine if blocking locks are required.
+*/
+void sqlite3WalDb(Wal *pWal, sqlite3 *db){
+  pWal->db = db;
+}
+
+/*
+** Take an exclusive WRITE lock. Blocking if so configured.
+*/
+static int walLockWriter(Wal *pWal){
+  int rc;
+  walEnableBlocking(pWal);
+  rc = walLockExclusive(pWal, WAL_WRITE_LOCK, 1);
+  walDisableBlocking(pWal);
+  return rc;
+}
+#else
+# define walEnableBlocking(x) 0
+# define walDisableBlocking(x)
+# define walLockWriter(pWal) walLockExclusive((pWal), WAL_WRITE_LOCK, 1)
+# define sqlite3WalDb(pWal)
+#endif   /* ifdef SQLITE_ENABLE_SETLK_TIMEOUT */
+
 /*
 ** Read the wal-index header from the wal-index and into pWal->hdr.
 ** If the wal-header appears to be corrupt, try to reconstruct the
@@ -2183,9 +2265,7 @@ static int walIndexReadHdr(Wal *pWal, int *pChanged){
       }
     }else{
       int bWriteLock = pWal->writeLock;
-      if( bWriteLock 
+      if( bWriteLock || SQLITE_OK==(rc = walLockWriter(pWal)) ){
-       || SQLITE_OK==(rc = walLockExclusive(pWal, WAL_WRITE_LOCK, 1)) 
-      ){
         pWal->writeLock = 1;
         if( SQLITE_OK==(rc = walIndexPage(pWal, 0, &page0)) ){
           badHdr = walIndexTryHdr(pWal, pChanged);
@@ -2737,65 +2817,6 @@ int sqlite3WalSnapshotRecover(Wal *pWal){
 }
 #endif /* SQLITE_ENABLE_SNAPSHOT */
 
-#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
-/*
-** Attempt to enable blocking locks. Blocking locks are enabled only if (a)
-** they are supported by the VFS, and (b) the database handle is configured 
-** with a busy-timeout. Return 1 if blocking locks are successfully enabled, 
-** or 0 otherwise.
-*/
-static int walEnableBlocking(sqlite3 *db, Wal *pWal){
-  int res = 0;
-  if( db->busyTimeout ){
-    int rc;
-    int tmout = db->busyTimeout;
-    rc = sqlite3OsFileControl(
-        pWal->pDbFd, SQLITE_FCNTL_LOCK_TIMEOUT, (void*)&tmout
-    );
-    res = (rc==SQLITE_OK);
-  }
-  return res;
-}
-
-/*
-** Disable blocking locks.
-*/
-static void walDisableBlocking(Wal *pWal){
-  int tmout = 0;
-  sqlite3OsFileControl(pWal->pDbFd, SQLITE_FCNTL_LOCK_TIMEOUT, (void*)&tmout);
-}
-
-/*
-** If parameter bLock is true, attempt to enable blocking locks, take
-** the WRITER lock, and then disable blocking locks. If blocking locks
-** cannot be enabled, no attempt to obtain the WRITER lock is made. Return 
-** an SQLite error code if an error occurs, or SQLITE_OK otherwise. It is not
-** an error if blocking locks can not be enabled.
-**
-** If the bLock parameter is false and the WRITER lock is held, release it.
-*/
-int sqlite3WalWriteLock(sqlite3 *db, Wal *pWal, int bLock){
-  int rc = SQLITE_OK;
-  assert( pWal->readLock<0 || bLock==0 );
-  if( bLock ){
-    if( walEnableBlocking(db, pWal) ){
-      rc = walLockExclusive(pWal, WAL_WRITE_LOCK, 1);
-      if( rc==SQLITE_OK ){
-        pWal->writeLock = 1;
-      }
-      walDisableBlocking(pWal);
-    }
-  }else if( pWal->writeLock ){
-    walUnlockExclusive(pWal, WAL_WRITE_LOCK, 1);
-    pWal->writeLock = 0;
-  }
-  return rc;
-}
-#else
-# define walEnableBlocking(x,y) 0
-# define walDisableBlocking(x)
-#endif   /* ifdef SQLITE_ENABLE_SETLK_TIMEOUT */
-
 /*
 ** Begin a read transaction on the database.
 **
@@ -2832,7 +2853,7 @@ int sqlite3WalBeginReadTransaction(Wal *pWal, int *pChanged){
     ** its intent. To avoid the race condition this leads to, ensure that
     ** there is no checkpointer process by taking a shared CKPT lock 
     ** before checking pInfo->nBackfillAttempted.  */
-    walEnableBlocking(pWal->dbSnapshot, pWal);
+    walEnableBlocking(pWal);
     rc = walLockShared(pWal, WAL_CKPT_LOCK);
     walDisableBlocking(pWal);
 
@@ -3666,7 +3687,8 @@ int sqlite3WalCheckpoint(
 
   /* Enable blocking locks, if possible. If blocking locks are successfully
   ** enabled, set xBusy2=0 so that the busy-handler is never invoked. */
-  if( walEnableBlocking(db, pWal) ){
+  sqlite3WalDb(pWal, db);
+  if( walEnableBlocking(pWal) ){
     xBusy2 = 0;
   }
 
@@ -3710,7 +3732,7 @@ int sqlite3WalCheckpoint(
   if( rc==SQLITE_OK ){
     walDisableBlocking(pWal);
     rc = walIndexReadHdr(pWal, &isChanged);
-    walEnableBlocking(db, pWal);
+    walEnableBlocking(pWal);
     if( isChanged && pWal->pDbFd->pMethods->iVersion>=3 ){
       sqlite3OsUnfetch(pWal->pDbFd, 0, 0);
     }
@@ -3743,6 +3765,7 @@ int sqlite3WalCheckpoint(
   }
 
   walDisableBlocking(pWal);
+  sqlite3WalDb(pWal, 0);
 
   /* Release the locks. */
   sqlite3WalEndWriteTransaction(pWal);
@@ -3869,13 +3892,9 @@ int sqlite3WalSnapshotGet(Wal *pWal, sqlite3_snapshot **ppSnapshot){
 */
 void sqlite3WalSnapshotOpen(
   Wal *pWal, 
-  sqlite3 *db, 
   sqlite3_snapshot *pSnapshot
 ){
   pWal->pSnapshot = (WalIndexHdr*)pSnapshot;
-#ifdef SQLITE_ENABLE_SETLK_TIMEOUT
-  pWal->dbSnapshot = db;
-#endif
 }
 
 /* 

src/wal.h

@@ -130,7 +130,7 @@ int sqlite3WalHeapMemory(Wal *pWal);
 
 #ifdef SQLITE_ENABLE_SNAPSHOT
 int sqlite3WalSnapshotGet(Wal *pWal, sqlite3_snapshot **ppSnapshot);
-void sqlite3WalSnapshotOpen(Wal *pWal, sqlite3*, sqlite3_snapshot *pSnapshot);
+void sqlite3WalSnapshotOpen(Wal *pWal, sqlite3_snapshot *pSnapshot);
 int sqlite3WalSnapshotRecover(Wal *pWal);
 int sqlite3WalSnapshotCheck(Wal *pWal, sqlite3_snapshot *pSnapshot);
 void sqlite3WalSnapshotUnlock(Wal *pWal);
@@ -147,7 +147,8 @@ int sqlite3WalFramesize(Wal *pWal);
 sqlite3_file *sqlite3WalFile(Wal *pWal);
 
 #ifdef SQLITE_ENABLE_SETLK_TIMEOUT
-int sqlite3WalWriteLock(sqlite3 *db, Wal *pWal, int bLock);
+int sqlite3WalWriteLock(Wal *pWal, int bLock);
+void sqlite3WalDb(Wal *pWal, sqlite3 *db);
 #endif
 
 #endif /* ifndef SQLITE_OMIT_WAL */