Re: [RFA] GDB/622 - clear current breakpoint in commands causestrouble

[Michael Snyder <msnyder@redhat.com>]

[-- Attachment #1: Type: text/plain, Size: 1429 bytes --]

Don Howard wrote:
> 
> On Thu, 22 Aug 2002, Michael Snyder wrote:
> 
> > Joel Brobecker wrote:
>
> > > > 2002-07-31  Joel Brobecker  <brobecker@gnat.com>
> > > >
> > > >         * cli/cli-scripts.c (copy_command_lines): New function.
> > > >         (make_cleanup_free_command_lines): Make this function non static.
> > > >
> > > >         * defs.h (copy_command_lines): Add definition.
> > > >         (make_cleanup_free_command_lines): Add definition.
> > > >
> > > >         * breakpoint.c (bpstat_do_actions): Execute a temporary copy of
> > > >         the command-list associated to each breakpoint hit, in order to
> > > >         avoid accessing a dangling pointer, in case one of the commands
> > > >         in the list causes the breakpoint to be deleted.
>
> > It looks OK to me, but I'd like to run it by Don Howard,
> > who has looked at this before.  Don, this patch looks a lot
> > simpler than the one you submitted (which, I think, died on
> > the vine (mea culpa)).  Do you think it will do the job?
>
> Yes this patch looks very much like one of my earlier attempts.  Joel's
> copy_command_lines() is simpler and catches a few bugs that I noticed in
> my implementation.  One question: is it important to use xstrdup() over
> plain strdup()?
> 
> You already pointed out the cleanup issues.  Once that is corrected, I'd
> recomend it.

Joel, Don, 

What do you think of the attached, to fix the cleanup issue?

[-- Attachment #2: joel1a.diff --]
[-- Type: text/plain, Size: 1429 bytes --]

Index: breakpoint.c
===================================================================
RCS file: /cvs/src/src/gdb/breakpoint.c,v
retrieving revision 1.82
diff -p -r1.82 breakpoint.c
*** breakpoint.c	23 Aug 2002 20:49:38 -0000	1.82
--- breakpoint.c	23 Aug 2002 23:47:18 -0000
*************** top:
*** 1927,1933 ****
    breakpoint_proceeded = 0;
    for (; bs != NULL; bs = bs->next)
      {
!       cmd = bs->commands;
        while (cmd != NULL)
  	{
  	  execute_control_command (cmd);
--- 1927,1939 ----
    breakpoint_proceeded = 0;
    for (; bs != NULL; bs = bs->next)
      {
!       struct cleanup *copy_cleanup;
! 
!       /* Use a temporary copy of the commands, as one command in the list
!          may cause this breakpoint and its commands to be deleted.  */
!       cmd = copy_command_lines (bs->commands);
!       copy_cleanup = make_cleanup_free_command_lines (&cmd);
! 
        while (cmd != NULL)
  	{
  	  execute_control_command (cmd);
*************** top:
*** 1945,1954 ****
  	goto top;
        else
  	bs->commands = NULL;
-     }
  
!   executing_breakpoint_commands = 0;
!   discard_cleanups (old_chain);
  }
  
  /* This is the normal print function for a bpstat.  In the future,
--- 1951,1960 ----
  	goto top;
        else
  	bs->commands = NULL;
  
!       do_cleanups (copy_cleanup);
!     }
!   do_cleanups (old_chain);
  }
  
  /* This is the normal print function for a bpstat.  In the future,