A fix and test case for Bug#5315 "mysql_change_user() doesn't free

prepared statements."


include/hash.h:
  New declaration for hash_reset() function. The old version was not used.
libmysql/client_settings.h:
  Declaration for mysql_detach_stmt_list().
libmysql/libmysql.c:
  Fix for bug#5315 "mysql_change_user() doesn't free prepared statements":
  add call to mysql_detach_stmt_list(prepared statements) to
  mysql_change_user(): all statements are freed by server, so client
  counterparts need to be marked as not usable.
mysys/hash.c:
  Fix for bug#5315 "mysql_change_user() doesn't free prepared statements":
  implementation of hash_reset(), which frees all hash elements
  and prepares the hash for reuse.
sql-common/client.c:
  Fix for bug#5315 "mysql_change_user() doesn't free prepared statements":
  implementation of mysql_detach_stmt_list(): zero connection pointer
  in given statement list, thus marking given statements as not usable.
sql/sql_class.cc:
  Fix for bug#5315 "mysql_change_user() doesn't free prepared statements":
  reset prepared statements map in THD::change_user().
sql/sql_class.h:
  Fix for bug#5315 "mysql_change_user() doesn't free prepared statements":
  implementation of Statement_map::reset().
  A little cleanup of ~Statement_map(): first empty names_hash, as st_hash
  has a free function, which will delete statements.
tests/client_test.c:
  A test case for bug #5315 "mysql_change_user() doesn't free prepared
  statements".

1 files changed, 30 insertions, 0 deletions

diff --git a/tests/client_test.c b/tests/client_test.c
index 0a4d635984d..accefb668a8 100644
--- a/tests/client_test.c
+++ b/tests/client_test.c
@@ -10391,6 +10391,34 @@ static void test_bug5194()
 }
 
 
+static void test_bug5315()
+{
+  MYSQL_STMT *stmt;
+  const char *stmt_text;
+  int rc;
+
+  myheader("test_bug5315");
+
+  stmt_text= "SELECT 1";
+  stmt= mysql_stmt_init(mysql);
+  rc= mysql_stmt_prepare(stmt, stmt_text, strlen(stmt_text));
+  DBUG_ASSERT(rc == 0);
+  mysql_change_user(mysql, opt_user, opt_password, current_db);
+  rc= mysql_stmt_execute(stmt);
+  DBUG_ASSERT(rc != 0);
+  if (rc)
+    printf("Got error (as expected):\n%s", mysql_stmt_error(stmt));
+  /* check that connection is OK */
+  mysql_stmt_close(stmt);
+  stmt= mysql_stmt_init(mysql);
+  rc= mysql_stmt_prepare(stmt, stmt_text, strlen(stmt_text));
+  DBUG_ASSERT(rc == 0);
+  rc= mysql_stmt_execute(stmt);
+  DBUG_ASSERT(rc == 0);
+  mysql_stmt_close(stmt);
+}
+
+
 /*
   Read and parse arguments and MySQL options from my.cnf
 */
@@ -10694,6 +10722,8 @@ int main(int argc, char **argv)
     test_bug5399();         /* check that statement id uniquely identifies
                                statement */
     test_bug5194();         /* bulk inserts in prepared mode */
+    test_bug5315();         /* check that mysql_change_user closes all
+                               prepared statements */
     /*
       XXX: PLEASE RUN THIS PROGRAM UNDER VALGRIND AND VERIFY THAT YOUR TEST
       DOESN'T CONTAIN WARNINGS/ERRORS BEFORE YOU PUSH.