Re: catch signals after calling execve()

[Roman Rakus]

Chet Ramey wrote:
> > > > After changing catching signals in bash - added CATCH_SIGNALS () macro -
> > > > we aren't catching them after calling execve(). This short patch fix it:
> > > > diff -up bash-3.2/execute_cmd.c.execve_catch_signal bash-3.2/execute_cmd.c
> > > > --- bash-3.2/execute_cmd.c.execve_catch_signal  2008-09-15
> > > > 12:20:18.000000000 +0200
> > > > +++ bash-3.2/execute_cmd.c      2008-09-15 12:20:55.000000000 +0200
> > > > @@ -3943,6 +3943,7 @@ shell_execve (command, args, env)
> > > >   SETOSTYPE (0);               /* Some systems use for USG/POSIX
> > > > semantics */
> > > >   execve (command, args, env);
> > > >   i = errno;                   /* error from execve() */
> > > > +  CATCH_SIGNALS ();
> > > >   SETOSTYPE (1);
> > > >     
> > > >         
> > >   
> > >       
> > I'm sorry. I didn't explain what is the problem.
> > The problem is, when bash tries to run any process by calling execve() 
> > from slow (maybe not only slow) hardware (for example mounted NFS). 
> > Driver of this hardware says kernel, that it needs to wait and kernel is 
> > waiting until signal handling is done. Probably I'm not saying it clearly.
> > Take a look at http://uwsg.iu.edu/hypermail/linux/kernel/0104.0/0743.html
> >     
>
> OK, but what does CATCH_SIGNALS do, and where did you add it?
>
> Chet
>
>   
Aaah... so sorry, I'm bit confused. CATCH_SIGNALS is only on RHEL-4 
system. There is similar macro in quit.h called CHECK_TERMSIG. So the 
patch is:
diff -up bash-3.2/execute_cmd.c.execve_catch_signals bash-3.2/execute_cmd.c
--- bash-3.2/execute_cmd.c.execve_catch_signals 2008-09-16 
14:28:25.000000000 +0200
+++ bash-3.2/execute_cmd.c      2008-09-16 14:52:14.000000000 +0200
@@ -99,6 +99,8 @@ extern int errno;
#  include "bashhist.h"
#endif

+#include "quit.h"
+
extern int posixly_correct;
extern int breaking, continuing, loop_level;
extern int expand_aliases;
@@ -3943,6 +3945,7 @@ shell_execve (command, args, env)
  SETOSTYPE (0);               /* Some systems use for USG/POSIX 
semantics */
  execve (command, args, env);
  i = errno;                   /* error from execve() */
+  CHECK_TERMSIG;
  SETOSTYPE (1);

  /* If we get to this point, then start checking out the file.

RR