Fix a race condition causing SQLite to use a busy-handler for an operation that should not.

FossilOrigin-Name: 6ab9ed8eef77781898375038ab05fc6e5f46b745e4906691393b8b1d90570eb6

1 files changed, 89 insertions, 0 deletions

diff --git a/test/walsetlk2.test b/test/walsetlk2.test
new file mode 100644
index 000000000..99366571d
--- /dev/null
+++ b/test/walsetlk2.test
@@ -0,0 +1,89 @@
+# 2025 Jan 24
+#
+# 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.
+#
+#***********************************************************************
+#
+# TESTRUNNER: slow
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+source $testdir/lock_common.tcl
+set testprefix walsetlk2
+
+ifcapable !wal {finish_test ; return }
+ifcapable !setlk_timeout {finish_test ; return }
+
+#-------------------------------------------------------------------------
+# Check that xShmLock calls are as expected for write transactions in
+# setlk mode.
+#
+reset_db
+
+do_execsql_test 1.0 {
+  PRAGMA journal_mode = wal;
+  CREATE TABLE t1(a, b, c);
+  INSERT INTO t1 VALUES(1, 2, 3);
+} {wal}
+db close
+
+testvfs tvfs
+tvfs script xShmLock_callback
+tvfs filter xShmLock
+
+set ::xshmlock [list]
+proc xShmLock_callback {method path name detail} {
+  lappend ::xshmlock $detail
+}
+
+sqlite3 db test.db -vfs tvfs
+db timeout 1000
+
+do_execsql_test 1.1 {
+  SELECT * FROM t1
+} {1 2 3}
+
+do_execsql_test 1.2 {
+  INSERT INTO t1 VALUES(4, 5, 6);
+}
+
+set ::xshmlock [list]
+do_execsql_test 1.3 {
+  INSERT INTO t1 VALUES(7, 8, 9);
+}
+
+do_test 1.4 {
+  set ::xshmlock
+} [list \
+  {0 1 lock exclusive}                             \
+  {4 1 lock exclusive} {4 1 unlock exclusive}      \
+  {4 1 lock shared}                                \
+  {0 1 unlock exclusive}                           \
+  {4 1 unlock shared}
+]
+
+do_execsql_test 1.5.1 { SELECT * FROM t1 } {1 2 3 4 5 6 7 8 9}
+set ::xshmlock [list]
+do_execsql_test 1.5.2 {
+  INSERT INTO t1 VALUES(10, 11, 12);
+}
+do_test 1.5.3 {
+  set ::xshmlock
+} [list \
+  {0 1 lock exclusive}                             \
+  {4 1 lock shared}                                \
+  {0 1 unlock exclusive}                           \
+  {4 1 unlock shared}
+]
+
+db close
+tvfs delete
+
+finish_test
+