[commit] Delete partial core file if gcore fails

[Daniel Jacobowitz <dan at codesourcery dot com>]

Noticed while tracking down a bug in a local patch.  There's a FIXME
in gcore.c that says we should delete core files on error; I agree,
and it's easy to do.

Tested on arm-none-eabi (which no longer leaves empty core files
around after saying that gcore is not supported) and on x86_64-linux;
committed to trunk.

-- 
Daniel Jacobowitz
CodeSourcery

2010-02-16  Daniel Jacobowitz  <dan@codesourcery.com>

	gdb/
	* gcore.c (do_bfd_delete_cleanup): New function.
	(gcore_command): Use it.  Discard the cleanup after success.
	(gcore_copy_callback): Delete dead code.

diff -urp gdb-merged-orig/gdb/gcore.c gdb-merged/gdb/gcore.c
--- gdb-merged-orig/gdb/gcore.c	2010-02-11 13:05:09.000000000 -0800
+++ gdb-merged/gdb/gcore.c	2010-02-14 09:50:42.000000000 -0800
@@ -102,6 +102,16 @@ write_gcore_file (bfd *obfd)
     }
 }
 
+static void
+do_bfd_delete_cleanup (void *arg)
+{
+  bfd *obfd = arg;
+  const char *filename = obfd->filename;
+
+  bfd_close (arg);
+  unlink (filename);
+}
+
 /* gcore_command -- implements the 'gcore' command.
    Generate a core file from the inferior process.  */
 
@@ -132,8 +142,8 @@ gcore_command (char *args, int from_tty)
   /* Open the output file.  */
   obfd = create_gcore_bfd (corefilename);
 
-  /* Need a cleanup that will close the file (FIXME: delete it?).  */
-  old_chain = make_cleanup_bfd_close (obfd);
+  /* Need a cleanup that will close and delete the file.  */
+  old_chain = make_cleanup (do_bfd_delete_cleanup, obfd);
 
   /* Call worker function.  */
   write_gcore_file (obfd);
@@ -141,9 +151,8 @@ gcore_command (char *args, int from_tty)
   /* Succeeded.  */
   fprintf_filtered (gdb_stdout, "Saved corefile %s\n", corefilename);
 
-  /* Clean-ups will close the output file and free malloc memory.  */
-  do_cleanups (old_chain);
-  return;
+  discard_cleanups (old_chain);
+  bfd_close (obfd);
 }
 
 static unsigned long
@@ -521,9 +530,6 @@ gcore_copy_callback (bfd *obfd, asection
 
   size = min (total_size, MAX_COPY_BYTES);
   memhunk = xmalloc (size);
-  /* ??? This is crap since xmalloc should never return NULL.  */
-  if (memhunk == NULL)
-    error (_("Not enough memory to create corefile."));
   old_chain = make_cleanup (xfree, memhunk);
 
   while (total_size > 0)