[PATCH] Add AC_REQUIRE_SHELL_FN

[Paolo Bonzini]

This adds AC_REQUIRE_SHELL_FN, which places the function in a "late"
diversion coming after the processing of --help and --version.

Ok?  I'll send out the twelve separate functionization patches soon, too.

Thanks,

Paolo

2008-10-18  Paolo Bonzini  <address@hidden>

        Add AC_REQUIRE_SHELL_FN and the SHELL_FN diversion.
        * lib/autoconf/general.m4 (AC_REQUIRE_SHELL_FN): New.
        (m4_divert(SHELL_FN)): New.

diff --git a/lib/autoconf/general.m4 b/lib/autoconf/general.m4
index beb3104..7c82a0b 100644
--- a/lib/autoconf/general.m4
+++ b/lib/autoconf/general.m4
@@ -104,6 +104,9 @@
 # - VERSION_END
 #   Tail of the handling of --version.
 #
+# - SHELL_FN
+#   Shell functions.
+#
 # - INIT_PREPARE
 #   Tail of initialization code.
 #
@@ -146,6 +149,8 @@ m4_define([_m4_divert(VERSION_FSF)],    201)
 m4_define([_m4_divert(VERSION_USER)],   202)
 m4_define([_m4_divert(VERSION_END)],    203)
 
+m4_define([_m4_divert(SHELL_FN)],       250)
+
 m4_define([_m4_divert(INIT_PREPARE)],   300)
 
 
@@ -186,6 +191,20 @@ m4_define([AC_OBSOLETE],
 
 
 ## ----------------------------- ##
+## Implementing shell functions. ##
+## ----------------------------- ##
+
+
+# AC_REQUIRE_SHELL_FN(NAME-TO-CHECK, COMMENT, BODY, [DIVERSION = SHELL_FN]
+# ------------------------------------------------------------------------
+# Same as AS_REQUIRE_SHELL_FN except that the default diversion comes
+# later in the script (speeding up configure --help and --version).
+AC_DEFUN([AC_REQUIRE_SHELL_FN],
+[AS_REQUIRE_SHELL_FN([$1], [$2], [$3], m4_default_quoted([$4], [SHELL_FN]))])
+
+
+
+## ----------------------------- ##
 ## Implementing Autoconf loops.  ##
 ## ----------------------------- ##