1 files changed, 62 insertions, 0 deletions
diff --git a/sysdeps/mach/hurd/jmp-unwind.c b/sysdeps/mach/hurd/jmp-unwind.c
new file mode 100644
index 0000000000..f7540f0dde
--- /dev/null
+++ b/sysdeps/mach/hurd/jmp-unwind.c
@@ -0,0 +1,62 @@
+/* _longjmp_unwind -- Clean up stack frames unwound by longjmp.  Hurd version.
+Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <setjmp.h>
+#include <hurd/signal.h>
+#include <hurd/userlink.h>
+#include <assert.h>
+
+/* This function is called by `longjmp' (with its arguments) to restore
+   active resources to a sane state before the frames code using them are
+   jumped out of.  */
+
+void
+_longjmp_unwind (jmp_buf env, int val)
+{
+  struct hurd_sigstate *ss = _hurd_self_sigstate ();
+  struct hurd_userlink *link;
+
+  /* All access to SS->active_resources must take place inside a critical
+     section where signal handlers cannot run.  */
+  __spin_lock (&ss->lock);
+  assert (! ss->critical_section);
+  ss->critical_section = 1;
+  __spin_unlock (&ss->lock);
+
+#ifndef _JMPBUF_UNWINDS
+ #error "sysdeps/MACHINE/jmp_buf.h fails to define _JMPBUF_UNWINDS"
+#endif
+
+  /* Iterate over the current thread's list of active resources.
+     Process the head portion of the list whose links reside
+     in stack frames being unwound by this jump.  */
+
+  for (link = ss->active_resources;
+       link && _JMPBUF_UNWINDS (env[0].__jmpbuf, link);
+       link = link->thread.next)
+    /* Remove this link from the resource's users list,
+       since the frame using the resource is being unwound.
+       This call returns nonzero if that was the last user.  */
+    if (_hurd_userlink_unlink (link))
+      /* One of the frames being unwound by the longjmp was the last user
+	 of its resource.  Call the cleanup function to deallocate it.  */
+      (*link->cleanup) (link->cleanup_data, env, val);
+
+  _hurd_critical_section_unlock (ss);
+}