bug #16017 (memory leaks in embedded server)

There actually was 3 different problems -
hash_user_connections wasn't cleaned
one strdupped database name wasn't freed
and stmt->mem_root wasn't cleaned as it was
replased with mysql->field_alloc for result
For the last one - i made the library using stmt's
fields to store result if it's the case.


include/mysql.h:
  statement pointer added to the advanced_command to be checked in
  embedded server
include/sql_common.h:
  stmt added to the cli_advanced_command interface
libmysql/libmysql.c:
  stmt pointer now sent to advanced_command
libmysqld/embedded_priv.h:
  it's enough to send database name to check_embedded_connection
libmysqld/lib_sql.cc:
  Now we store result directly in the MYSQL_STMT structure to
  avoid extra copying
libmysqld/libmysqld.c:
  it's enough to only send database pointer to check_embedded_connection
sql-common/client.c:
  stmt fake attribute added to cli_advanced_command
sql/sql_parse.cc:
  hash_user_connections isn't used if no access checks compiled

2 files changed, 16 insertions, 4 deletions

diff --git a/include/mysql.h b/include/mysql.h
index 0949937814c..143f6752c46 100644
--- a/include/mysql.h
+++ b/include/mysql.h
@@ -216,6 +216,7 @@ enum mysql_rpl_type
 };
 
 struct st_mysql_methods;
+struct st_mysql_stmt;
 
 typedef struct st_mysql
 {
@@ -269,6 +270,12 @@ typedef struct st_mysql
     from mysql_stmt_close if close had to cancel result set of this object.
   */
   my_bool *unbuffered_fetch_owner;
+  /*
+    In embedded server it points to the statement that is processed
+    in the current query. We store some results directly in statement
+    fields then.
+  */
+  struct st_mysql_stmt *current_stmt;
 } MYSQL;
 
 typedef struct st_mysql_res {
@@ -636,7 +643,8 @@ typedef struct st_mysql_methods
 			      unsigned long header_length,
 			      const char *arg,
 			      unsigned long arg_length,
-			      my_bool skip_check);
+			      my_bool skip_check,
+                              MYSQL_STMT *stmt);
   MYSQL_DATA *(*read_rows)(MYSQL *mysql,MYSQL_FIELD *mysql_fields,
 			   unsigned int fields);
   MYSQL_RES * (*use_result)(MYSQL *mysql);
@@ -724,8 +732,11 @@ int		STDCALL mysql_drop_db(MYSQL *mysql, const char *DB);
 */
 
 #define simple_command(mysql, command, arg, length, skip_check) \
-  (*(mysql)->methods->advanced_command)(mysql, command,         \
-					NullS, 0, arg, length, skip_check)
+  (*(mysql)->methods->advanced_command)(mysql, command, NullS,  \
+                                        0, arg, length, skip_check, NULL)
+#define stmt_command(mysql, command, arg, length, stmt) \
+  (*(mysql)->methods->advanced_command)(mysql, command, NullS,  \
+                                        0, arg, length, 1, stmt)
 unsigned long net_safe_read(MYSQL* mysql);
 
 #ifdef __NETWARE__
diff --git a/include/sql_common.h b/include/sql_common.h
index c07a4a831bb..52d766d77d2 100644
--- a/include/sql_common.h
+++ b/include/sql_common.h
@@ -33,7 +33,8 @@ void mysql_read_default_options(struct st_mysql_options *options,
 my_bool
 cli_advanced_command(MYSQL *mysql, enum enum_server_command command,
 		     const char *header, ulong header_length,
-		     const char *arg, ulong arg_length, my_bool skip_check);
+		     const char *arg, ulong arg_length, my_bool skip_check,
+                     MYSQL_STMT *stmt);
 
 void set_stmt_errmsg(MYSQL_STMT * stmt, const char *err, int errcode,
 		     const char *sqlstate);