Fix a startup race condition that could occur if a wal file grows from 0 bytes while...

FossilOrigin-Name: 2c14f3832e0e21c4e68b556d5592860fcd79b6ca21db6c47f52a240b24559a9a

diff --git a/manifest b/manifest
index 5df4334576903cf0d89510b7382b41bc58cd9293..46958d254828c4d6f129967ee4ea5a225d5272a1 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Merge\sthe\slatest\strunk\senhancements\sinto\sthe\sbegin-concurrent-pnu-wal2\nbranch.
-D 2022-12-21T20:43:53.573
+C Fix\sa\sstartup\srace\scondition\sthat\scould\soccur\sif\sa\swal\sfile\sgrows\sfrom\s0\sbytes\swhile\sa\sBEGIN\sCONCURRENT\stransaction\sis\srunning.
+D 2023-01-12T15:44:48.827
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -505,11 +505,11 @@ F ext/wasm/README.md ef39861aa21632fdbca0bdd469f78f0096f6449a720f3f39642594af503
 F ext/wasm/api/EXPORTED_FUNCTIONS.sqlite3-api c5eaceabb9e759aaae7d3101a4a3e542f96ab2c99d89a80ce20ec18c23115f33
 F ext/wasm/api/EXPORTED_RUNTIME_METHODS.sqlite3-api 1ec3c73e7d66e95529c3c64ac3de2470b0e9e7fbf7a5b41261c367cf4f1b7287
 F ext/wasm/api/README.md 77a2f1f2fc60a35def7455dffc8d3f2c56385d6ac5c6cecc60fa938252ea2c54
-F ext/wasm/api/extern-post-js.c-pp.js 8923f76c3d2213159e12d641dc750523ead5c848185dc4996fae5cc12397f88d w ext/wasm/api/extern-post-js.js
+F ext/wasm/api/extern-post-js.c-pp.js 8923f76c3d2213159e12d641dc750523ead5c848185dc4996fae5cc12397f88d
 F ext/wasm/api/extern-pre-js.js cc61c09c7a24a07dbecb4c352453c3985170cec12b4e7e7e7a4d11d43c5c8f41
 F ext/wasm/api/post-js-footer.js cd0a8ec768501d9bd45d325ab0442037fb0e33d1f3b4f08902f15c34720ee4a1
 F ext/wasm/api/post-js-header.js 47b6b281f39ad59fa6e8b658308cd98ea292c286a68407b35ff3ed9cfd281a62
-F ext/wasm/api/pre-js.c-pp.js b88499dc303c21fc3f55f2c364a0f814f587b60a95784303881169f9e91c1d5f w ext/wasm/api/pre-js.js
+F ext/wasm/api/pre-js.c-pp.js b88499dc303c21fc3f55f2c364a0f814f587b60a95784303881169f9e91c1d5f
 F ext/wasm/api/sqlite3-api-cleanup.js 680d5ccfff54459db136a49b2199d9f879c8405d9c99af1dda0cc5e7c29056f4
 F ext/wasm/api/sqlite3-api-glue.js 63daa4b9c36faa4c338a32a06eb142869b9ae4885a3e01aad473e1b45357089f
 F ext/wasm/api/sqlite3-api-oo1.js c0c4ccc269cccee657ffd03f094da7e270e1367b7928926b3730d543555a12a6
@@ -518,7 +518,7 @@ F ext/wasm/api/sqlite3-api-worker1.js e94ba98e44afccfa482874cd9acb325883ade50ed1
 F ext/wasm/api/sqlite3-license-version-header.js a661182fc93fc2cf212dfd0b987f8e138a3ac98f850b1112e29b5fbdaecc87c3
 F ext/wasm/api/sqlite3-opfs-async-proxy.js 7795b84b66a7a8dedc791340709b310bb497c3c72a80bef364fa2a58e2ddae3f
 F ext/wasm/api/sqlite3-v-helper.js 6f6c3e390a72e08b0a5b16a0d567d7af3c04d172831853a29d72a6f1dd40ff24
-F ext/wasm/api/sqlite3-vfs-opfs.c-pp.js 66daf6fb6843bea615fe193109e1542efbeca24f560ee9da63375a910bb48115 w ext/wasm/api/sqlite3-api-opfs.js
+F ext/wasm/api/sqlite3-vfs-opfs.c-pp.js 66daf6fb6843bea615fe193109e1542efbeca24f560ee9da63375a910bb48115
 F ext/wasm/api/sqlite3-wasi.h 25356084cfe0d40458a902afb465df8c21fc4152c1d0a59b563a3fba59a068f9
 F ext/wasm/api/sqlite3-wasm.c 44ce4cf12318b0577d8222cf59132617ab9925ca3cf5fbb8c7b30d1e947c13b5
 F ext/wasm/api/sqlite3-worker1-promiser.js 0c7a9826dbf82a5ed4e4f7bf7816e825a52aff253afbf3350431f5773faf0e4b
@@ -562,8 +562,8 @@ F ext/wasm/sql/001-sudoku.sql 35b7cb7239ba5d5f193bc05ec379bcf66891bce6f2a5b3879f
 F ext/wasm/test-opfs-vfs.html 1f2d672f3f3fce810dfd48a8d56914aba22e45c6834e262555e685bce3da8c3f
 F ext/wasm/test-opfs-vfs.js f09266873e1a34d9bdb6d3981ec8c9e382f31f215c9fd2f9016d2394b8ae9b7b
 F ext/wasm/tester1-worker.html d43f3c131d88f10d00aff3e328fed13c858d674ea2ff1ff90225506137f85aa9
-F ext/wasm/tester1.c-pp.html d34bef3d48e5cbc1c7c06882ad240fec49bf88f5f65696cc2c72c416933aa406 w ext/wasm/tester1.html
-F ext/wasm/tester1.c-pp.js c45c46cdae1949d426ee12a736087ab180beacc2a20cd829f9052b957adf9ac9 w ext/wasm/tester1.js
+F ext/wasm/tester1.c-pp.html d34bef3d48e5cbc1c7c06882ad240fec49bf88f5f65696cc2c72c416933aa406
+F ext/wasm/tester1.c-pp.js c45c46cdae1949d426ee12a736087ab180beacc2a20cd829f9052b957adf9ac9
 F ext/wasm/tests/opfs/concurrency/index.html 86d8ac435074d1e7007b91105f4897f368c165e8cecb6a9aa3d81f5cf5dcbe70
 F ext/wasm/tests/opfs/concurrency/test.js a98016113eaf71e81ddbf71655aa29b0fed9a8b79a3cdd3620d1658eb1cc9a5d
 F ext/wasm/tests/opfs/concurrency/worker.js 0a8c1a3e6ebb38aabbee24f122693f1fb29d599948915c76906681bb7da1d3d2
@@ -737,7 +737,7 @@ F src/vdbetrace.c fe0bc29ebd4e02c8bc5c1945f1d2e6be5927ec12c06d89b03ef2a4def34bf8
 F src/vdbevtab.c f99b275366c5fc5e2d99f734729880994ab9500bdafde7fae3b02d562b9d323c
 F src/vtab.c b2f993aa954078985bc40317bb2140fe0880a08a7440f3a428b60fce74636808
 F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
-F src/wal.c 393ffbef8381b50265a3f0de5cf3c68d0df6c6867df429c5719c2446e9254126
+F src/wal.c 1d26e49c69c8a3adf88428a679bfaaefd7e1f7d9f8dd51685e3a558db3f16f3b
 F src/wal.h 7a733af13b966ecb81872ce397e862116b3575ea53245b90b139a2873ee87825
 F src/walker.c f890a3298418d7cba3b69b8803594fdc484ea241206a8dfa99db6dd36f8cbb3b
 F src/where.c d0d8e3cb2c11e77ba0f8f9ed8eada9d84dbd377167cdcf387b8eeb824c35a3ad
@@ -900,12 +900,13 @@ F test/concfault.test 500f17c3fcfe7705114422bcc6ddd3c740001a43
 F test/concfault2.test 34b3fd258836aa305475d00e804c7450ade92f0de0bf9fa620e701446669bb12
 F test/concurrent.test a0248ec6e3e79a5948453649cf86b5b359175cba55ea636b15426d6f0fa6c3da
 F test/concurrent2.test 847cd11edc82229a95e1eaf88b55c974430b0f669cefd67a453d274e3480981c
-F test/concurrent3.test 530671ac706f6a1d0f4992dbdd33a86408330d03cd90fb9e82ecb1b27f5fd081
+F test/concurrent3.test 82923fc2ea7321144b4448f98ea38aa316ddceef9020a392c5f6dea536506434
 F test/concurrent4.test e0b12cd467137e50259df3b4f837507e82aaa07c35941c88664dc8ed1d089c44
 F test/concurrent5.test 0c16cbf7446af162a14e6def30445e94016064eb994e5aa4ebb2bebc59554176
 F test/concurrent6.test a7860e9ca13bb5fb76bcf41c5524fbfa9c37e6e258ecf84ffb5748a272488c67
 F test/concurrent7.test b96fa5c4cfdf8d5c0bc66b6934214500bad0260884a736f054ccc76e81aae85d
 F test/concurrent8.test b93937e74a8efb8b84f2fea7595b53418c5f29777bbe9cbdb5dc219b3dd72a7d
+F test/concurrent9.test 92a7315092e54c7377e58cfce1c158aa55f6915a026aff27da00db088676101b
 F test/conflict.test ac0667090f66130ac77d5fb764655558ca6600dd6d88f670ca9123b61c448337
 F test/conflict2.test 5557909ce683b1073982f5d1b61dfb1d41e369533bfdaf003180c5bc87282dd1
 F test/conflict3.test 81865d9599609aca394fb3b9cd5f561d4729ea5b176bece3644f6ecb540f88ac
@@ -2102,8 +2103,9 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P a090de41be2a727cdb98f02df3d793d94101ca7004c1023c86ae2ad55b5f9c5b 21ebd4cfcf843925cf8eaeb2f7e196713dba116cf618aea9f9f40e31f6aa6653
-R 544b11c1cde1fc2ec0d45186182d0afc
-U drh
-Z b08c936308294a8392ff255929f0a76f
+P bcab19d21be42121f1ea3961aedbbe463c60d85d0a3dd8b9593040d217bac3a7
+Q +c1feca4ddaa93fa1cf75e8df061967995a18d726a23f4006d239d3e03c8570df
+R f7f153aa0f2932683653732f2072b6cf
+U dan
+Z bea728a05177d93a8ab6622f5da482dd
 # Remove this line to create a well-formed Fossil manifest.

diff --git a/manifest.uuid b/manifest.uuid
index 2e24b400d583103d51522e1dcab1c1eb960d6e8c..70a35dc84838f00e30c3b5e5958b576c42c74ffe 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-bcab19d21be42121f1ea3961aedbbe463c60d85d0a3dd8b9593040d217bac3a7
\ No newline at end of file
+2c14f3832e0e21c4e68b556d5592860fcd79b6ca21db6c47f52a240b24559a9a
\ No newline at end of file

diff --git a/src/wal.c b/src/wal.c
index 5fe3c6ff1d612d62960dd9179bf81e63af5de41c..ce09efb0a54a48a206a9ffdcd8219fab3cd67960 100644 (file)
--- a/src/wal.c
+++ b/src/wal.c
@@ -4316,7 +4316,11 @@ int sqlite3WalLockForCommit(
 int sqlite3WalUpgradeSnapshot(Wal *pWal){
   int rc = SQLITE_OK;
   assert( pWal->writeLock );
+
+  assert( pWal->szPage==pWal->hdr.szPage );
   memcpy(&pWal->hdr, (void*)walIndexHdr(pWal), sizeof(WalIndexHdr));
+  assert( pWal->szPage==pWal->hdr.szPage || pWal->szPage==0 );
+  pWal->szPage = pWal->hdr.szPage;
 
   /* If this client has its read-lock on slot aReadmark[0] and the entire
   ** wal has not been checkpointed, switch it to a different slot. Otherwise

diff --git a/test/concurrent3.test b/test/concurrent3.test
index cc8038890276fe3167604200de45c2028d6b1cfa..8ca8a9887adc63a92756ff3b5f1c321a64f4a060 100644 (file)
--- a/test/concurrent3.test
+++ b/test/concurrent3.test
@@ -226,6 +226,9 @@ foreach {tn nRepeat oplist} {
   # }
 }
 
+catch { db close }
+sqlite3_shutdown
+test_sqlite3_log
 
 
 finish_test

diff --git a/test/concurrent9.test b/test/concurrent9.test
new file mode 100644 (file)
index 0000000..c514f55
--- /dev/null
+++ b/test/concurrent9.test
@@ -0,0 +1,55 @@
+# 2023 January 12
+#
+# 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.
+#
+#*************************************************************************
+# This file implements regression tests for SQLite library.
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+set testprefix concurrent9
+
+do_execsql_test 1.0 {
+  CREATE TABLE t1(x);
+  INSERT INTO t1 VALUES(1), (2);
+  CREATE TABLE t2(y);
+  INSERT INTO t2 VALUES('a'), ('b');
+  PRAGMA journal_mode = wal;
+} {wal}
+
+db close
+
+#-------------------------------------------------------------------------
+# Fix a problem that may occur if a BEGIN CONCURRENT transaction is 
+# started when the wal file is completely empty and committed after
+# it has been initialized by some other connection.
+#
+sqlite3 db  test.db
+sqlite3 db2 test.db
+
+do_execsql_test -db db  1.1 {
+  BEGIN CONCURRENT;
+    INSERT INTO t2 VALUES('c');
+}
+
+do_execsql_test -db db2  1.2 {
+  INSERT INTO t1 VALUES(3);
+}
+
+do_execsql_test -db db  1.3 {
+  COMMIT;
+}
+
+do_execsql_test -db db2  1.4 {
+  SELECT * FROM t1;
+  SELECT * FROM t2;
+} {1 2 3 a b c}
+
+finish_test
+