Bug#44521 Executing a stored procedure as a prepared statement can sometimes cause

          an assertion in a debug build.

The reason is that the C API doesn't support multiple result sets for prepared
statements and attempting to execute a stored routine which returns multiple result
sets sometimes lead to a network error. The network error sets the diagnostic area
prematurely which later leads to the assert when an attempt is made to set a second
server state.

This patch fixes the issue by changing the scope of the error code returned by
sp_instr_stmt::execute() to include any error which happened during the execution.
To assure that Diagnostic_area::is_sent really mean that the message was sent all
network related functions are checked for return status.

libmysqld/lib_sql.cc:
  * Changed prototype to return success/failure status on net_send_error_packet(),
    net_send_ok(), net_send_eof(), write_eof_packet().
mysql-test/r/sp_notembedded.result:
  * Added test case for bug 44521
mysql-test/t/sp_notembedded.test:
  * Added test case for bug 44521
sql/protocol.cc:
  * Changed prototype to return success/failure status on net_send_error_packet(),
    net_send_ok(), net_send_eof(), write_eof_packet().
sql/protocol.h:
  * Changed prototype to return success/failure status on net_send_error_packet(),
    net_send_ok(), net_send_eof(), write_eof_packet().
sql/sp_head.cc:
  * Changed prototype to return success/failure status on net_send_error_packet(),
    net_send_ok(), net_send_eof(), write_eof_packet().

1 files changed, 1 insertions, 1 deletions

diff --git a/sql/protocol.h b/sql/protocol.h
index a4770e9b6e3..251ba6fbc33 100644
--- a/sql/protocol.h
+++ b/sql/protocol.h
@@ -173,7 +173,7 @@ public:
 };
 
 void send_warning(THD *thd, uint sql_errno, const char *err=0);
-void net_send_error(THD *thd, uint sql_errno=0, const char *err=0);
+bool net_send_error(THD *thd, uint sql_errno=0, const char *err=0);
 void net_end_statement(THD *thd);
 bool send_old_password_request(THD *thd);
 uchar *net_store_data(uchar *to,const uchar *from, size_t length);