1 files changed, 58 insertions, 0 deletions
diff --git a/libc/signal/sysv_signal.c b/libc/signal/sysv_signal.c
new file mode 100644
index 000000000..5756ec484
--- /dev/null
+++ b/libc/signal/sysv_signal.c
@@ -0,0 +1,58 @@
+/* Copyright (C) 1991, 1992, 1996, 1997 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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <signal.h>
+
+#undef signal
+
+/* Tolerate non-threads versions of Posix */
+#ifndef SA_ONESHOT
+#define SA_ONESHOT 0
+#endif
+#ifndef SA_NOMASK
+#define SA_NOMASK 0
+#endif
+#ifndef SA_INTERRUPT
+#define SA_INTERRUPT 0
+#endif
+
+/* Set the handler for the signal SIG to HANDLER,
+   returning the old handler, or SIG_ERR on error.  */
+__sighandler_t __sysv_signal (int sig, __sighandler_t handler)
+{
+  struct sigaction act, oact;
+
+  /* Check signal extents to protect __sigismember.  */
+  if (handler == SIG_ERR || sig < 1 || sig >= NSIG)
+    {
+      __set_errno (EINVAL);
+      return SIG_ERR;
+    }
+
+  act.sa_handler = handler;
+  if (__sigemptyset (&act.sa_mask) < 0)
+    return SIG_ERR;
+  act.sa_flags = SA_ONESHOT | SA_NOMASK | SA_INTERRUPT;
+  act.sa_flags &= ~SA_RESTART;
+  if (sigaction (sig, &act, &oact) < 0)
+    return SIG_ERR;
+
+  return oact.sa_handler;
+}
+