[cogl] build: Allow to forcefully disable the usage cairo

[Damien Lespiau <dlespiau src gnome org>]

commit 8e949ff5606d4eb5a2f0c1658dca60b816203a05
Author: Damien Lespiau <damien lespiau intel com>
Date:   Mon May 16 18:08:49 2011 +0100

    build: Allow to forcefully disable the usage cairo
    
    Provide an option to disable cairo usage in the debugging code even if
    we find the pc file.

 configure.ac |   14 ++++++++++++--
 1 files changed, 12 insertions(+), 2 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 620acd2..fb3361c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -164,6 +164,17 @@ AC_ARG_ENABLE(
   enable_debug=default
 )
 
+PKG_CHECK_EXISTS([CAIRO], [cairo], [have_cairo=yes])
+AC_ARG_ENABLE(
+  [cairo],
+  [AC_HELP_STRING([--enable-cairo=@<:@no/yes@:>@], [Control Cairo usage in Cogl debugging code @<:@default=]default[@:>@])],
+  [],
+  enable_cairo=default
+)
+AS_IF([test "x$enable_cairo" = "xyes" && test "x$have_cairo" != "xyes"],
+      [AC_MSG_ERROR([Could not find Cairo])])
+
+
 AS_CASE(
   [$enable_debug],
   [yes],
@@ -172,8 +183,7 @@ AS_CASE(
     COGL_EXTRA_CFLAGS="$COGL_EXTRA_CFLAGS -DCOGL_GL_DEBUG -DCOGL_OBJECT_DEBUG -DCOGL_HANDLE_DEBUG -DCOGL_ENABLE_DEBUG"
 
     # debugging code can use cairo to dump the atlas
-    PKG_CHECK_EXISTS([CAIRO], [cairo], [have_cairo=yes])
-    AS_IF([test "x$have_cairo" = "xyes"],
+    AS_IF([test "x$have_cairo" = "xyes" && test "x$enable_cairo" != "xno"],
           [
             COGL_PKG_REQUIRES="$COGL_PKG_REQUIRES cairo"
             AC_DEFINE([HAVE_CAIRO], [1], [Whether we have cairo or not])