[RFA] Make attach_command exception-safe

[Vladimir Prus <vladimir@codesourcery.com>]

When attach_command executes, it might disable stdin. It further might
throw, and does not enable stdin in that case. For CLI case, top-level
event loop will catch the exception and enable stdin. For MI case, MI
interpreter catches the exception in order to print the error message,
and of course it has no idea about any stdin disabling.

This patch makes attach_command exception-safe, enabling stdin on
throw.

OK?

- Volodya

	* infcmd.c (attach_command): Call async_enable_stdin
	if exception is thrown.

---
 ChangeLog.csl |    6 ++++++
 gdb/infcmd.c  |    4 ++++
 2 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/ChangeLog.csl b/ChangeLog.csl
index 9f4f686..5699492 100644
--- a/ChangeLog.csl
+++ b/ChangeLog.csl
@@ -1,3 +1,9 @@
+2008-08-28  Vladimir Prus  <vladimir@codesourcery.com>
+
+	Make attach_command exception-safe
+        * infcmd.c (attach_command): Call async_enable_stdin
+        if exception is thrown.
+
 2008-08-19  Pedro Alves  <pedro@codesourcery.com>
 
 	* infcmd.c (post_create_inferior_1): If the solist is global,
diff --git a/gdb/infcmd.c b/gdb/infcmd.c
index feb045a..f0d3a6f 100644
--- a/gdb/infcmd.c
+++ b/gdb/infcmd.c
@@ -2084,6 +2084,7 @@ attach_command (char *args, int from_tty)
   char *exec_file;
   char *full_exec_path = NULL;
   int async_exec = 0;
+  struct cleanup *back_to = make_cleanup (null_cleanup, NULL);
 
   dont_repeat ();		/* Not for the faint of heart */
 
@@ -2139,6 +2140,7 @@ attach_command (char *args, int from_tty)
     {
       /* Simulate synchronous execution */
       async_disable_stdin ();
+      make_cleanup ((make_cleanup_ftype *)async_enable_stdin, NULL);
     }
 
   target_attach (args, from_tty);
@@ -2181,6 +2183,7 @@ attach_command (char *args, int from_tty)
 	  add_continuation (inferior_thread (),
 			    attach_command_continuation, a,
 			    attach_command_continuation_free_args);
+	  discard_cleanups (back_to);
 	  return;
 	}
 
@@ -2188,6 +2191,7 @@ attach_command (char *args, int from_tty)
     }
 
   attach_command_post_wait (args, from_tty, async_exec);
+  discard_cleanups (back_to);
 }
 
 /*
-- 
1.5.3.5