Preserve message printed before abort.

The terminal output etc is not visible in a core file.  The new
libc-internal variable __abort_msg will point to a string with the
message which has been printed before the abort in case abort is
called from inside libc.  BZ #10217

1 files changed, 16 insertions, 1 deletions

diff --git a/sysdeps/posix/libc_fatal.c b/sysdeps/posix/libc_fatal.c
index c611b84363..4f11c0fcb0 100644
--- a/sysdeps/posix/libc_fatal.c
+++ b/sysdeps/posix/libc_fatal.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1993,1994,1995,1997,2000,2004,2005
+/* Copyright (C) 1993-1995,1997,2000,2004,2005,2009
 	Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -17,6 +17,7 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
+#include <atomic.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <paths.h>
@@ -123,6 +124,20 @@ __libc_message (int do_abort, const char *fmt, ...)
 
       if (TEMP_FAILURE_RETRY (__writev (fd, iov, nlist)) == total)
 	written = true;
+
+      char *buf = do_abort ? malloc (total + 1) : NULL;
+      if (buf != NULL)
+	{
+	  char *wp = buf;
+	  for (int cnt = 0; cnt < nlist; ++cnt)
+	    wp = mempcpy (wp, iov[cnt].iov_base, iov[cnt].iov_len);
+	  *wp = '\0';
+
+	  /* We have to free the old buffer since the application might
+	     catch the SIGABRT signal.  */
+	  char *old = atomic_exchange_acq (&__abort_msg, buf);
+	  free (old);
+	}
     }
 
   va_end (ap);