[PATCH 5/7] autoconf: use AC_CONFIG_COMMANDS instead of ad-hoc 'config.mak.append'

[Stefano Lattarini <stefano.lattarini@gmail.com>]

This will allow "./config.status --recheck; ./config.status" to work
correctly as a mean of reconfiguring the tree with the same configure
argument used in the previous "./configure" invocation.

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>
---
 configure.ac | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/configure.ac b/configure.ac
index 5fb9734..64eecbc 100644
--- a/configure.ac
+++ b/configure.ac
@@ -7,7 +7,21 @@
 # --------------------------
 # Append LINE to file ${config_append}
 AC_DEFUN([GIT_CONF_SUBST],
-         [echo "$1=$2" >> "${config_append}"])
+   [AC_REQUIRE([GIT_CONF_SUBST_INIT])
+   config_appended_defs="$config_appended_defs${newline}$1=$2"])
+
+
+# GIT_CONF_SUBST_INIT
+# -------------------
+# Prepare shell variables and autoconf machine required by later calls
+# to GIT_CONF_SUBST.
+AC_DEFUN([GIT_CONF_SUBST_INIT], 
+    [config_appended_defs=; newline='
+'
+    AC_CONFIG_COMMANDS([$config_file],
+                       [echo "$config_appended_defs" >> "$config_file"],
+                       [config_file=$config_file
+                        config_appended_defs="$config_appended_defs"])])
 
 # GIT_ARG_SET_PATH(PROGRAM)
 # -------------------------
@@ -133,11 +147,8 @@ AC_INIT([git], [@@GIT_VERSION@@], [git@vger.kernel.org])
 AC_CONFIG_SRCDIR([git.c])
 
 config_file=config.mak.autogen
-config_append=config.mak.append
 config_in=config.mak.in
 
-echo "# ${config_append}.  Generated by configure." > "${config_append}"
-
 # Directories holding "saner" versions of common or POSIX binaries.
 AC_ARG_WITH([sane-tool-path],
   [AS_HELP_STRING(
@@ -1041,9 +1052,5 @@ AC_SUBST(PTHREAD_LIBS)
 AC_SUBST(NO_PTHREADS)
 
 ## Output files
-AC_CONFIG_FILES(["${config_file}":"${config_in}":"${config_append}"])
+AC_CONFIG_FILES(["${config_file}":"${config_in}"])
 AC_OUTPUT
-
-
-## Cleanup
-rm -f "${config_append}"
-- 
1.7.10.2.1067.g553d16e