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-rw-r--r--sysdeps/unix/sysv/linux/sigstack.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/sigstack.c b/sysdeps/unix/sysv/linux/sigstack.c
new file mode 100644
index 0000000000..bca7dc634e
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+++ b/sysdeps/unix/sysv/linux/sigstack.c
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+/* Emulate sigstack function using sigalstack.
+   Copyright (C) 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
+
+   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., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <signal.h>
+
+
+int
+sigstack (ss, oss)
+     const struct sigstack *ss;
+     struct sigstack *oss;
+{
+  stack_t sas;
+  stack_t *sasp = NULL;
+  stack_t osas;
+  stack_t *osasp = oss == NULL ? NULL : &osas;
+  int result;
+
+  if (ss != NULL)
+    {
+      /* We have to convert the information.  */
+      sas.ss_sp = ss->ss_sp;
+      sas.ss_flags = ss->ss_onstack ? SS_ONSTACK : 0;
+
+      /* For the size of the stack we have no value we can pass to the
+	 kernel.  This is why this function should not be used.  We simply
+	 assume that all the memory down to address zero (in case the stack
+	 grows down) is available.  */
+      sas.ss_size = ss->ss_sp - NULL;
+
+      sasp = &sas;
+    }
+
+  /* Call the kernel.  */
+  result = __sigaltstack (sasp, osasp);
+
+  /* Convert the result, if wanted and possible.  */
+  if (result == 0 && oss != NULL)
+    {
+      oss->ss_sp = osas.ss_sp;
+      oss->ss_onstack = (osas.ss_flags & SS_ONSTACK) != 0;
+    }
+
+  return result;
+}