Prepare for radical source tree reorganization. zack/build-layout-experiment

All top-level files and directories are moved into a temporary storage
directory, REORG.TODO, except for files that will certainly still
exist in their current form at top level when we're done (COPYING,
COPYING.LIB, LICENSES, NEWS, README), all old ChangeLog files (which
are moved to the new directory OldChangeLogs, instead), and the
generated file INSTALL (which is just deleted; in the new order, there
will be no generated files checked into version control).

1 files changed, 66 insertions, 0 deletions

diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/sigstack.c b/REORG.TODO/sysdeps/unix/sysv/linux/sigstack.c
new file mode 100644
index 0000000000..94d9935fc4
--- /dev/null
+++ b/REORG.TODO/sysdeps/unix/sysv/linux/sigstack.c
@@ -0,0 +1,66 @@
+/* Emulate sigstack function using sigaltstack.
+   Copyright (C) 1998-2017 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 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <signal.h>
+#include <stddef.h>
+#include <sys/syscall.h>
+
+
+#ifdef __NR_sigaltstack
+int
+sigstack (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;
+}
+
+link_warning (sigstack, "the `sigstack' function is dangerous.  `sigaltstack' should be used instead.")
+#else
+# include <signal/sigstack.c>
+#endif