From 55a64c1bd5319cb2cd11c9f8bc67508d427dc378 Mon Sep 17 00:00:00 2001
From: Georg Richter <georg@mariadb.com>
Date: Fri, 2 Oct 2020 09:47:52 +0200
Subject: [PATCH] Fix for CONC-504: reset stmt->result.rows when executing
 mysql_stmt_next_result

While in text protocol the number of rows is resetted in mysql_store/use_result
in binary protocol we need to explicitly reset it when switching to next result set.
---
 libmariadb/mariadb_stmt.c     |  1 +
 unittest/libmariadb/ps_bugs.c | 43 +++++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/libmariadb/mariadb_stmt.c b/libmariadb/mariadb_stmt.c
index f72c0a56..1cb7cee7 100644
--- a/libmariadb/mariadb_stmt.c
+++ b/libmariadb/mariadb_stmt.c
@@ -2374,6 +2374,7 @@ int STDCALL mysql_stmt_next_result(MYSQL_STMT *stmt)
   }
 
   stmt->field_count= stmt->mysql->field_count;
+  stmt->result.rows= 0;
 
   return(rc);
 }
diff --git a/unittest/libmariadb/ps_bugs.c b/unittest/libmariadb/ps_bugs.c
index c9292b91..61f412a5 100644
--- a/unittest/libmariadb/ps_bugs.c
+++ b/unittest/libmariadb/ps_bugs.c
@@ -5232,7 +5232,50 @@ static int test_returning(MYSQL *mysql)
   return OK;
 }
 
+static int test_conc504(MYSQL *mysql)
+{
+  int rc;
+  MYSQL_STMT *stmt= mysql_stmt_init(mysql);
+  const char *sp= "CREATE PROCEDURE p1()\n" \
+                  "BEGIN\n"\
+                  "  SELECT 1;\n"\
+                  "  SELECT 2;\n"\
+                  "  SELECT 3;\n"\
+                  "END";
+
+  rc= mysql_query(mysql, "DROP PROCEDURE IF EXISTS p1");
+  check_mysql_rc(rc, mysql);
+
+  rc= mysql_query(mysql, sp);
+  check_mysql_rc(rc, mysql);
+
+  rc= mysql_stmt_prepare(stmt, SL("CALL p1()"));
+  check_stmt_rc(rc, stmt);
+
+  rc= mysql_stmt_execute(stmt);
+  check_stmt_rc(rc, stmt);
+
+  mysql_stmt_store_result(stmt);
+  FAIL_IF(mysql_stmt_num_rows(stmt) != 1, "Expected 1 row");
+
+  mysql_stmt_next_result(stmt);
+  mysql_stmt_store_result(stmt);
+  FAIL_IF(mysql_stmt_num_rows(stmt) != 1, "Expected 1 row");
+
+  mysql_stmt_next_result(stmt);
+  mysql_stmt_store_result(stmt);
+  FAIL_IF(mysql_stmt_num_rows(stmt) != 1, "Expected 1 row");
+
+  mysql_stmt_close(stmt);
+
+  rc= mysql_query(mysql, "DROP PROCEDURE p1");
+  check_mysql_rc(rc, mysql);
+
+  return OK;
+}
+
 struct my_tests_st my_tests[] = {
+  {"test_conc504", test_conc504, TEST_CONNECTION_DEFAULT, 0, NULL, NULL},
   {"test_returning", test_returning, TEST_CONNECTION_DEFAULT, 0, NULL, NULL},
   {"test_mdev_21920", test_mdev_21920, TEST_CONNECTION_DEFAULT, 0, NULL, NULL},
   {"test_maxparam", test_maxparam, TEST_CONNECTION_NEW, 0, NULL, NULL},