[acinclude.m4] Add compat macros for autoconf 2.59

acinclude.m4

@@ -4,10 +4,30 @@ dnl [m4_newline] didn't appear until autoconf 2.62
 m4_ifdef([m4_newline],,[m4_define([m4_newline],[
 ])])
 
-dnl [m4_foreach_w] wasn't available in 2.59
+dnl These are not available in autoconf 2.59
+
 m4_ifdef([m4_foreach_w],,[m4_define([m4_foreach_w],
 [m4_foreach([$1], m4_split(m4_normalize([$2]), [ ]), [$3])])])
 
+m4_ifdef([AS_CASE],,[
+m4_define([_AS_CASE],
+[m4_if([$#], 0, [m4_fatal([$0: too few arguments: $#])],
+       [$#], 1, [  *) $1 ;;],
+       [$#], 2, [  $1) m4_default([$2], [:]) ;;],
+       [  $1) m4_default([$2], [:]) ;;
+$0(m4_shift2($@))])dnl
+])
+m4_defun([AS_CASE],
+[m4_ifval([$2$3],
+[case $1 in
+_AS_CASE(m4_shift($@))
+esac
+])dnl
+])# AS_CASE
+])
+
+m4_ifdef([m4_shift2],, [m4_define([m4_shift2], [m4_shift(m4_shift($@))])])
+
 
 dnl ==========================================================================
 
@@ -22,3 +42,14 @@ m4_define([CAIRO_PARSE_VERSION],dnl
 			    [A-Z], [a-z])dnl
 )dnl
 
+dnl ==========================================================================
+
+m4_pattern_forbid([^cr_])
+
+dnl AC_AUTOCONF_VERSION was introduced in 2.62, so its definition works as
+dnl a conditional on version >= 2.62.  Older versions did not call
+dnl m4_pattern_allow from AC_DEFINE and friends.  To avoid lots of warnings we
+dnl only forbid CAIRO_ if autoconf is recent enough.
+m4_ifdef([AC_AUTOCONF_VERSION],
+[m4_pattern_forbid([CAIRO])],
+[m4_pattern_forbid([_CAIRO])])

build/aclocal.cairo.m4

@@ -1,10 +1,7 @@
-
 dnl ==========================================================================
 dnl
 dnl Cairo-specific macros
 dnl
-m4_pattern_forbid([CAIRO])
-m4_pattern_forbid([^cr_])
 
 dnl ==========================================================================