From: Dmitry V. Levin <ldv@altlinux.org>
Date: Wed, 7 Dec 2016 10:58:24 +0000 (+0000)
Subject: m4: introduce st_SAVE_VAR and st_RESTORE_VAR macros
X-Git-Tag: v4.15~18
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=c26d031c1fbe8bd1703714cefa57cc5b4374796d;p=strace

m4: introduce st_SAVE_VAR and st_RESTORE_VAR macros

These new macros are going to be needed for the upcoming
AX_PROG_CC_FOR_BUILD change.

* m4/st_save_restore_var.m4: New file.
---

diff --git a/m4/st_save_restore_var.m4 b/m4/st_save_restore_var.m4
new file mode 100644
index 00000000..2939380a
--- /dev/null
+++ b/m4/st_save_restore_var.m4
@@ -0,0 +1,7 @@
+AC_DEFUN([st_SAVE_VAR], [dnl
+AS_IF([test -n "${$1+set}"], [st_saved_$1="${$1}"; unset $1])
+])
+
+AC_DEFUN([st_RESTORE_VAR], [dnl
+AS_IF([test -n "${st_saved_$1+set}"], [$1="${st_saved_$1}"; unset st_saved_$1])
+])