[PATCH] Add compiled in default sysroot

Similar to the --with-pc-path option. It works just like the existing
PKG_CONFIG_SYSROOT_DIR environment variable, but compiled in.
The environment variable overrides this default setting if set.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
---
 Makefile.am  |    6 +++++-
 configure.in |    6 ++++++
 main.c       |    9 +++++++--
 3 files changed, 18 insertions(+), 3 deletions(-)

Index: pkg-config-0.25/Makefile.am
===================================================================
--- pkg-config-0.25.orig/Makefile.am
+++ pkg-config-0.25/Makefile.am
@@ -28,8 +28,12 @@ EXTRA_DIST = $(m4_DATA) $(man_MANS) READ
 bin_PROGRAMS = pkg-config
 AM_CFLAGS=@WARN_CFLAGS@
 
+if USE_SYSROOT
+sysroot_includes = -DPKG_CONFIG_SYSROOT="\"$(sysroot)\""
+endif
+
 INCLUDES=-DPKG_CONFIG_PC_PATH="\"$(pc_path)\"" $(included_glib_includes) \
-	$(popt_includes)
+	$(popt_includes) $(sysroot_includes)
 
 pkg_config_SOURCES= \
 	pkg.h \
Index: pkg-config-0.25/configure.in
===================================================================
--- pkg-config-0.25.orig/configure.in
+++ pkg-config-0.25/configure.in
@@ -32,6 +32,12 @@ fi
 
 PKG_CONFIG_FIND_PC_PATH
 
+AC_ARG_WITH(sysroot,
+ [  --with-sysroot         Use sysroot <dir> by default ],
+ [ sysroot="$withval" ])
+
+AC_SUBST([sysroot])
+AM_CONDITIONAL(USE_SYSROOT, test "x$sysroot" != "x")
 #
 # Code taken from gtk+-2.0's configure.in.
 #
Index: pkg-config-0.25/main.c
===================================================================
--- pkg-config-0.25.orig/main.c
+++ pkg-config-0.25/main.c
@@ -36,10 +36,14 @@
 #undef STRICT
 #endif
 
+#ifndef PKG_CONFIG_SYSROOT
+#define PKG_CONFIG_SYSROOT NULL
+#endif
+
 static int want_debug_spew = 0;
 static int want_verbose_errors = 0;
 static int want_stdout_errors = 0;
-char *pcsysrootdir = NULL;
+char *pcsysrootdir = PKG_CONFIG_SYSROOT;
 
 void
 debug_spew (const char *format, ...)
@@ -311,7 +315,8 @@ main (int argc, char **argv)
       add_search_dirs(PKG_CONFIG_PC_PATH, G_SEARCHPATH_SEPARATOR_S);
     }
 
-  pcsysrootdir = getenv ("PKG_CONFIG_SYSROOT_DIR");
+  if (getenv ("PKG_CONFIG_SYSROOT_DIR"))
+	  pcsysrootdir = getenv ("PKG_CONFIG_SYSROOT_DIR");
   if (pcsysrootdir)
     {
       define_global_variable ("pc_sysrootdir", pcsysrootdir);