Fix a problem with rolling back hot journals using the unix-dotfile VFS.

FossilOrigin-Name: 4ae3300b79e03381fd7f1033bb7978bb6367369790f17c3bdacac51e205edaf9

manifest

@@ -1,5 +1,5 @@
-C Remove\ssome\sdead\sJS\scode\sand\supdate\ssome\sJS\sdocs.
+C Fix\sa\sproblem\swith\srolling\sback\shot\sjournals\susing\sthe\sunix-dotfile\sVFS.
-D 2024-06-11T17:04:43.812
+D 2024-06-11T20:03:32.695
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -739,7 +739,7 @@ F src/os.h 1ff5ae51d339d0e30d8a9d814f4b8f8e448169304d83a7ed9db66a65732f3e63
 F src/os_common.h 6c0eb8dd40ef3e12fe585a13e709710267a258e2c8dd1c40b1948a1d14582e06
 F src/os_kv.c 4d39e1f1c180b11162c6dc4aa8ad34053873a639bac6baae23272fc03349986a
 F src/os_setup.h 6011ad7af5db4e05155f385eb3a9b4470688de6f65d6166b8956e58a3d872107
-F src/os_unix.c 08ca53844f4bf8eafb18b0a9076c84afac41da912315a5cfbe9e704d4c10c090
+F src/os_unix.c 582eb7e4aa4fee66dd9475cf7325a6753890266020ba1670c36ed8b9babd5a46
 F src/os_win.c 6ff43bac175bd9ed79e7c0f96840b139f2f51d01689a638fd05128becf94908a
 F src/os_win.h 7b073010f1451abe501be30d12f6bc599824944a
 F src/pager.c 9beb80f6e330dd63c5d8ba0f7a7f3a55fff22067a68d424949c389bfc6fa0c56
@@ -1388,7 +1388,7 @@ F test/lock.test be4fe08118fb988fed741f429b7dd5d65e1c90db
 F test/lock2.test 5242d8ac4e2d59c403aebff606af449b455aceff
 F test/lock3.test f271375930711ae044080f4fe6d6eda930870d00
 F test/lock4.test 27143363eda1622f03c133efc8db808fc331afd973486cb571ea71cd717d37b8
-F test/lock5.test c6c5e0ebcb21c61a572870cc86c0cb9f14cede38
+F test/lock5.test 69d7991e39c3fade9b6e46403c1386bcd21a4808796c9c6f60f17d0fdcec266f
 F test/lock6.test ad5b387a3a8096afd3c68a55b9535056431b0cf5
 F test/lock7.test 49f1eaff1cdc491cc5dee3669f3c671d9f172431
 F test/lock_common.tcl 2f3f7f2e9637f93ccf609df48ef5b27a50278b6b1cd752b445d52262e5841413
@@ -2195,8 +2195,11 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 06e6f64533563ab9c059b773e5f0d78085df716f2624e547b7259f6789c3ffe0
+P 6935ac71bad3d36cc519f0325ae4447a674f257309d020cdc0741160fcce0580
-R 79d342ace6fd539450d6954e121ef97a
+R a6be376671415b32f13dc00f1cf159ee
-U stephan
+T *branch * unix-dotfile-fix
-Z 878c1bfba19ab8a7570c53af656f275c
+T *sym-unix-dotfile-fix *
+T -sym-trunk *
+U dan
+Z 82729b2f1037b9035a8ecef1ba94fcd8
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-6935ac71bad3d36cc519f0325ae4447a674f257309d020cdc0741160fcce0580
+4ae3300b79e03381fd7f1033bb7978bb6367369790f17c3bdacac51e205edaf9

src/os_unix.c

@@ -2279,26 +2279,17 @@ static int nolockClose(sqlite3_file *id) {
 
 /*
 ** This routine checks if there is a RESERVED lock held on the specified
-** file by this or any other process. If such a lock is held, set *pResOut
+** file by this or any other process. The caller always holds a SHARED
-** to a non-zero value otherwise *pResOut is set to zero.  The return value
+** lock when it is called. This means that no other connection could
-** is set to SQLITE_OK unless an I/O error occurs during lock checking.
+** hold a RESERVED lock, as unix-dotfile uses just a single exclusive lock -
-**
+** the presence of the dotfile - for all 4 VFS locks. So this function sets
-** In dotfile locking, either a lock exists or it does not.  So in this
+** (*pResOut) to 0 (no other connection holds RESERVED) and returns SQLITE_OK.
-** variation of CheckReservedLock(), *pResOut is set to true if any lock
-** is held on the file and false if the file is unlocked.
 */
 static int dotlockCheckReservedLock(sqlite3_file *id, int *pResOut) {
-  int rc = SQLITE_OK;
-  int reserved = 0;
-  unixFile *pFile = (unixFile*)id;
-
   SimulateIOError( return SQLITE_IOERR_CHECKRESERVEDLOCK; );
-
+  assert( ((unixFile*)id)->eFileLock>=SHARED_LOCK );
-  assert( pFile );
+  *pResOut = 0;
-  reserved = osAccess((const char*)pFile->lockingContext, 0)==0;
+  return SQLITE_OK;
-  OSTRACE(("TEST WR-LOCK %d %d %d (dotlock)\n", pFile->h, rc, reserved));
-  *pResOut = reserved;
-  return rc;
 }
 
 /*

test/lock5.test

@@ -11,10 +11,10 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this script is database locks.
 #
-# $Id: lock5.test,v 1.6 2008/12/04 12:34:16 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
+set testprefix lock5
 
 # This file is only run if using the unix backend compiled with the
 # SQLITE_ENABLE_LOCKING_STYLE macro.
@@ -101,10 +101,7 @@ do_test lock5-dotfile.X {
 #####################################################################
 
 forcedelete test.db
-if {[catch {sqlite3 db test.db -vfs unix-flock} msg]} {
+if {0==[catch {sqlite3 db test.db -vfs unix-flock} msg]} {
-  finish_test
-  return
-}
 
 do_test lock5-flock.1 {
   sqlite3 db test.db -vfs unix-flock
@@ -149,13 +146,19 @@ do_test lock5-flock.8 {
   db2 close
 } {}
 
+}
+
 #####################################################################
 
+reset_db
+
 do_test lock5-none.1 {
   sqlite3 db test.db -vfs unix-none
   sqlite3 db2 test.db -vfs unix-none
   execsql { PRAGMA mmap_size = 0 } db2
   execsql {
+    CREATE TABLE t1(a, b);
+    INSERT INTO t1 VALUES(1, 2);
     BEGIN;
     INSERT INTO t1 VALUES(3, 4);
   }
@@ -193,4 +196,62 @@ ifcapable lock_proxy_pragmas {
   set env(SQLITE_FORCE_PROXY_LOCKING) $::using_proxy
 }
 
+#####################################################################
+reset_db
+
+# 1. Create a large database using the unix-dotfile VFS
+# 2. Write a large transaction to the db, so that the cache spills, but do
+#    not commit it.
+# 3. Make a copy of the database files on disk.
+# 4. Try to read from the copy using unix-dotfile VFS. This fails because
+#    the dotfile still exists, so SQLite things the database is locked.
+# 5. Remove the dotfile.
+# 6. Try to read the db again. This time, the old transaction is rolled
+#    back and the read permitted.
+#
+do_test 2.dotfile.1 {
+  sqlite3 db test.db -vfs unix-dotfile
+  execsql {
+    PRAGMA cache_size = 10;
+    CREATE TABLE t1(x, y, z);
+    CREATE INDEX t1x ON t1(x);
+    WITH s(i) AS (
+      SELECT 1 UNION ALL SELECT i+1 FROM s WHERE i<1000
+    )
+    INSERT INTO t1 SELECT hex(randomblob(20)), hex(randomblob(500)), i FROM s;
+  }
+} {}
+
+do_execsql_test 2.dotfile.2 {
+  BEGIN;
+    UPDATE t1 SET z=z+1, x=hex(randomblob(20));
+}
+
+do_test 2.dotfile.3 {
+  list                            \
+    [file exists test.db]         \
+    [file exists test.db-journal] \
+    [file exists test.db.lock]
+} {1 1 1}
+
+do_test 2.dotfile.4 {
+  forcecopy test.db test.db2
+  forcecopy test.db-journal test.db2-journal
+  file mkdir test.db2.lock
+
+  sqlite3 db2 test.db2 -vfs unix-dotfile
+  catchsql {
+    SELECT count(*) FROM t1;
+  } db2
+} {1 {database is locked}}
+
+do_test 2.dotfile.5 {
+  file delete test.db2.lock
+  execsql {
+    PRAGMA integrity_check
+  } db2
+} {ok}
+
 finish_test
+
+