add m4 macro to check X extension

SVN revision: 28724

legacy/ecore/m4/check_x_extension.m4

@@ -0,0 +1,35 @@
+dnl use: ECORE_CHECK_X_EXT(Foo, header, lib, func)
+AC_DEFUN([AC_CHECK_X_EXTENSION],
+[
+pushdef([UP], translit([$1], [a-z], [A-Z]))dnl
+pushdef([DOWN], translit([$1], [A-Z], [a-z]))dnl
+
+UP[]_CFLAGS=""
+UP[]_LIBS=""
+use_[]DOWN="no"
+
+SAVE_CFLAGS=$CFLAGS
+CFLAGS="$x_cflags $x_includes"
+AC_CHECK_HEADER(X11/extensions/$2,
+  [
+   AC_CHECK_LIB($3, $4,
+     [
+      AC_DEFINE(ECORE_[]UP, 1, [Build support for $1])
+      UP[]_LIBS="-l$3"
+      use_[]DOWN="yes"
+     ],
+     [ use_[]DOWN="no" ],
+     [ $x_libs ]
+   )
+  ],
+  [ use_[]DOWN="no" ],
+  [ #include <X11/Xlib.h> ]
+)
+CFLAGS=$SAVE_CFLAGS
+
+AC_SUBST(UP[]_CFLAGS)
+AC_SUBST(UP[]_LIBS)
+
+popdef([UP])
+popdef([DOWN])
+])