Introduce common/gdb_setjmp.h

This commit creates a new file, common/gdb_setjmp.h, to hold some
portability macros for setjmp/longjmp et al. that are used by the
exceptions subsystem and by the demangler crash catcher.

gdb/ChangeLog:

	* common/gdb_setjmp.h: New file.
	* Makefile.in (HFILES_NO_SRCDIR): Add common/gdb_setjmp.h.
	* configure.ac: Move sigsetjmp check...
	* common/common.m4: ...here.
	* configure: Regenerate.
	* cp-support.c (SIGJMP_BUF): Delete.
	(SIGSETJMP): Likewise.
	(SIGLONGJMP): Likewise.
	* exceptions.h (gdb_setjmp.h): Include.
	(setjmp.h): Do not include.
	(EXCEPTIONS_SIGJMP_BUF): Delete.
	(EXCEPTIONS_SIGSETJMP): Likewise.
	(EXCEPTIONS_SIGLONGJMP): Likewise.
	Replace all uses of EXCEPTIONS_SIG* macros with SIG* macros
	from gdb_setjmp.h.
	* exceptions.c: Likewise.

gdb/gdbserver/ChangeLog:

	* config.in: Regenerate.
	* configure: Likewise.

2 files changed, 45 insertions, 0 deletions

diff --git a/gdb/common/common.m4 b/gdb/common/common.m4
index 426df79..7aabd07 100644
--- a/gdb/common/common.m4
+++ b/gdb/common/common.m4
@@ -33,4 +33,15 @@ AC_DEFUN([GDB_AC_COMMON], [
   AC_CHECK_FUNCS([fdwalk getrlimit pipe pipe2 socketpair])
 
   AC_CHECK_DECLS([strerror, strstr])
+
+  dnl Check if sigsetjmp is available.  Using AC_CHECK_FUNCS won't
+  dnl do since sigsetjmp might only be defined as a macro.
+AC_CACHE_CHECK([for sigsetjmp], gdb_cv_func_sigsetjmp,
+[AC_TRY_COMPILE([
+#include <setjmp.h>
+], [sigjmp_buf env; while (! sigsetjmp (env, 1)) siglongjmp (env, 1);],
+gdb_cv_func_sigsetjmp=yes, gdb_cv_func_sigsetjmp=no)])
+if test $gdb_cv_func_sigsetjmp = yes; then
+  AC_DEFINE(HAVE_SIGSETJMP, 1, [Define if sigsetjmp is available. ])
+fi
 ])
diff --git a/gdb/common/gdb_setjmp.h b/gdb/common/gdb_setjmp.h
new file mode 100644
index 0000000..aba50a4
--- /dev/null
+++ b/gdb/common/gdb_setjmp.h
@@ -0,0 +1,34 @@
+/* Portability wrappers for setjmp and longjmp.
+   Copyright (C) 1986-2014 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef GDB_SETJMP_H
+#define GDB_SETJMP_H
+
+#include <setjmp.h>
+
+#ifdef HAVE_SIGSETJMP
+#define SIGJMP_BUF		sigjmp_buf
+#define SIGSETJMP(buf)		sigsetjmp((buf), 1)
+#define SIGLONGJMP(buf,val)	siglongjmp((buf), (val))
+#else
+#define SIGJMP_BUF		jmp_buf
+#define SIGSETJMP(buf)		setjmp(buf)
+#define SIGLONGJMP(buf,val)	longjmp((buf), (val))
+#endif
+
+#endif /* GDB_SETJMP_H */