1 files changed, 79 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/sysv4/sigaction.c b/sysdeps/unix/sysv/sysv4/sigaction.c
new file mode 100644
index 0000000000..68fd7a1846
--- /dev/null
+++ b/sysdeps/unix/sysv/sysv4/sigaction.c
@@ -0,0 +1,79 @@
+/* Copyright (C) 1994, 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 <ansidecl.h>
+#include <errno.h>
+#include <signal.h>
+#include <stddef.h>
+
+static __sighandler_t user_handlers[NSIG];
+
+extern int __context_syscall (int, struct sigcontext *);
+extern int __sigaction_syscall (int,
+				const struct sigaction *, struct sigaction *);
+
+static void
+trampoline (int sig, int code, struct sigcontext *context)
+{
+  (*(void (*) (int, int, struct sigcontext *)) user_handlers[sig])
+    (sig, code, context);
+  __context_syscall (1, context);
+}
+
+/* If ACT is not NULL, change the action for SIG to *ACT.
+   If OACT is not NULL, put the old action for SIG in *OACT.  */
+int
+DEFUN(__sigaction, (sig, act, oact),
+      int sig AND CONST struct sigaction *act AND struct sigaction *oact)
+{
+  struct sigaction myact;
+  __sighandler_t ohandler;
+
+  if (sig <= 0 || sig >= NSIG)
+    {
+      errno = EINVAL;
+      return -1;
+    }
+
+  ohandler = user_handlers[sig];
+
+  if (act != NULL)
+    {
+      user_handlers[sig] = act->sa_handler;
+      if (act->sa_handler != SIG_DFL && act->sa_handler != SIG_IGN)
+	{
+	  myact = *act;
+	  act = &myact;
+	  act->sa_handler = (__sighandler_t) trampoline;
+	}
+    }
+
+  if (__sigaction_syscall (sig, act, oact) < 0)
+    {
+      /* The syscall got an error.  Restore the old handler and return -1.  */
+      user_handlers[sig] = ohandler;
+      return -1;
+    }
+
+  if (oact != NULL && oact->sa_handler == (__sighandler_t) trampoline)
+    oact->sa_handler = ohandler;
+
+  return 0;
+}
+
+weak_alias (__sigaction, sigaction)