mysql_stmt_reset now expects ok/error packet from server.

libmysql/libmysql.c:
  Make advanced_command check client reply
sql/sql_prepare.cc:
  mysql_stmt_reset now sends ok/error reply to the client.
tests/client_test.c:
  Memory leak fixed.

libmysql/libmysql.c

@@ -3992,7 +3992,8 @@ my_bool STDCALL mysql_stmt_reset(MYSQL_STMT *stmt)
   
   mysql= stmt->mysql->last_used_con;
   int4store(buff, stmt->stmt_id);		/* Send stmt id to server */
-  if ((*mysql->methods->advanced_command)(mysql, COM_RESET_STMT,buff,MYSQL_STMT_HEADER,0,0,1))
+  if ((*mysql->methods->advanced_command)(mysql, COM_RESET_STMT, buff,
+                                          MYSQL_STMT_HEADER,0,0,0))
   {
     set_stmt_errmsg(stmt, mysql->net.last_error, mysql->net.last_errno, 
                     mysql->net.sqlstate);

sql/sql_prepare.cc

@@ -1555,18 +1555,20 @@ set_params_data_err:
 
 
 /*
-    Reset a prepared statement, in case there was an error in send_longdata.
-    Note: we don't send any reply to that command.
+    Reset a prepared statement in case there was a recoverable error.
   SYNOPSIS
     mysql_stmt_reset()
     thd		Thread handle
     packet	Packet with stmt id 
 
   DESCRIPTION
-    This function is useful when one gets an error after calling
-    mysql_stmt_getlongdata() and wants to reset the handle
-    so that one can call execute again.
-    See also bug #1664
+    This function resets statement to the state it was right after prepare.
+    It can be used to:
+     - clear an error happened during mysql_stmt_send_long_data
+     - cancel long data stream for all placeholders without
+       having to call mysql_stmt_execute.
+    Sends 'OK' packet in case of success (statement was reset)
+    or 'ERROR' packet (unrecoverable error/statement not found/etc).
 */
 
 void mysql_stmt_reset(THD *thd, char *packet)
@@ -1577,7 +1579,7 @@ void mysql_stmt_reset(THD *thd, char *packet)
   
   DBUG_ENTER("mysql_stmt_reset");
 
-  if (!(stmt= find_prepared_statement(thd, stmt_id, "reset", DONT_SEND_ERROR)))
+  if (!(stmt= find_prepared_statement(thd, stmt_id, "reset", SEND_ERROR)))
     DBUG_VOID_RETURN;
 
   stmt->get_longdata_error= 0;
@@ -1587,6 +1589,8 @@ void mysql_stmt_reset(THD *thd, char *packet)
     mysql_stmt_send_long_data() call.
   */
   reset_stmt_params(stmt);
+
+  send_ok(thd);
   
   DBUG_VOID_RETURN;
 }

tests/client_test.c

@@ -163,8 +163,11 @@ MYSQL_STMT *STDCALL
 mysql_simple_prepare(MYSQL  *mysql, const char *query)
 {
   MYSQL_STMT *stmt= mysql_stmt_init(mysql);
-  if (mysql_stmt_prepare(stmt, query, strlen(query)))
+  if (stmt && mysql_stmt_prepare(stmt, query, strlen(query)))
+  {
+    mysql_stmt_close(stmt);
     return 0;
+  }
   return stmt;
 }