Bug#21557 entries in the general query log truncated at 1000 characters.

The general log write function (general_log_print) uses printf style
arguments which need to be pre-processed, meaning that the all arguments
are copied to a single buffer and the problem is that the buffer size is
constant (1022 characters) but queries can be much larger then this.

The solution is to introduce a new log write function that accepts a
buffer and it's length as arguments. The function is to be used when
a formatted output is not required, which is the case for almost all
query write-to-log calls.

This is a incompatible change with respect to the log format of prepared
statements.


mysql-test/r/log_tables.result:
  Add test case result for Bug#21557
mysql-test/t/log_tables.test:
  Add test case for Bug#21557
sql/log.cc:
  Introduce the logger function general_log_write which is similar to
  general_log_print but accepts a single buffer and the buffer length.
  The function doesn't perform any formatting and sends the buffer
  directly to the underlying log handlers.
sql/log.h:
  Introduce the logger function general_log_write.
sql/log_event.cc:
  Pass the query buffer directly to the logger function, formatting
  is not required on this case.
sql/mysql_priv.h:
  Prototype for the logger function general_log_write.
sql/sp_head.cc:
  Pass the query buffer directly to the logger function, formatting
  is not required on this case.
sql/sql_parse.cc:
  Pass the buffer directly to the logger function when formatting
  is not required.
sql/sql_prepare.cc:
  Don't log the statement id, it avoids making a extra copy of the query
  and the query is not truncated anymore if it exceeds the limit.

1 files changed, 4 insertions, 0 deletions

diff --git a/sql/log.h b/sql/log.h
index e597c986794..bef0101c8b5 100644
--- a/sql/log.h
+++ b/sql/log.h
@@ -499,6 +499,8 @@ public:
   void lock_exclusive() { rw_wrlock(&LOCK_logger); }
   void unlock() { rw_unlock(&LOCK_logger); }
   bool is_log_table_enabled(uint log_table_type);
+  bool log_command(THD *thd, enum enum_server_command command);
+
   /*
     We want to initialize all log mutexes as soon as possible,
     but we cannot do it in constructor, as safe_mutex relies on
@@ -518,6 +520,8 @@ public:
                       ulonglong current_utime);
   bool general_log_print(THD *thd,enum enum_server_command command,
                          const char *format, va_list args);
+  bool general_log_write(THD *thd, enum enum_server_command command,
+                         const char *query, uint query_length);
 
   /* we use this function to setup all enabled log event handlers */
   int set_handlers(uint error_log_printer,