MySQL Bugs: #54238: bad assignment in handle_slave_sql for skip_slave

Bug #54238	bad assignment in handle_slave_sql for skip_slave_counter
Submitted:	4 Jun 2010 16:16	Modified:	10 Oct 2010 19:44
Reporter:	Mark Callaghan	Email Updates:
Status:	Duplicate	Impact on me:	None
Category:	MySQL Server: Replication	Severity:	S3 (Non-critical)
Version:	5.1.47	OS:	Any
Assigned to:	Assigned Account	CPU Architecture:	Any
Tags:	replication, skip_slave_counter

Description:
This code looks bad:
1) strmake() should handle the null termination
2) assigment of '\0' should be done to *pos not to pos

  if (rli->slave_skip_counter)
  {
    char *pos;
    pos= strmake(saved_log_name, rli->group_relay_log_name, FN_REFLEN - 1);
    pos= '\0';
    pos= strmake(saved_master_log_name, rli->group_master_log_name, FN_REFLEN - 1);
    pos= '\0';
    saved_log_pos= rli->group_relay_log_pos;
    saved_master_log_pos= rli->group_master_log_pos;
    saved_skip= rli->slave_skip_counter;
  }

The change appears to be from:
3366.1.2     alfranio.correia@sun.com                    20100504

How to repeat:
read the code

Suggested fix:
Add a regression test that will catch this

This isn't serious as there is no read of pos after "pos = '\0'" is run to set pos to NULL.

But future changes could make this a real problem.

I think the idea is to throw away the return for strmake.  In which case maybe pos= NULL would be better than '/0'?

A patch for this bug has been committed. After review, it may
be pushed to the relevant source trees for release in the next
version. You can access the patch from:

  http://lists.mysql.com/commits/113126

3470 Alfranio Correia	2010-07-08
      BUG#54238 bad assignment in handle_slave_sql for skip_slave_counter
      
      Code cleanup: removed unused variable and bad assignment.

This issues was fixed in the patch for 
  BUG#45288: pb2 returns a lot of compilation warnings on linux

Duplicate of BUG#45288.