Fixed to give a better warning if pkg-config is not installed

pixman/autogen.sh

@@ -5,6 +5,21 @@ set -e
 
 ARGV0=$0
 
+if test -z "$ACLOCAL_FLAGS"; then
+    acdir=`aclocal --print-ac-dir`
+    if [ ! -f $acdir/pkg.m4 ]; then
+	echo "$ARGV0: Error: Could not find pkg-config macros."
+	echo "        (Looked in $acdir/pkg.m4)"
+	echo "        If pkg.m4 is available in /another/directory, please set"
+	echo "        ACLOCAL_FLAGS=\"-I /another/directory\""
+	echo "        Otherwise, please install pkg-config."
+	echo ""
+	echo "pkg-config is available from:"
+	echo "http://www.freedesktop.org/software/pkgconfig/"
+	exit 1
+    fi
+fi
+
 if test -z "$*"; then
   echo "$ARGV0:	Note: \`./configure' will be run with no arguments."
   echo "		If you wish to pass any to it, please specify them on the"
@@ -19,7 +34,7 @@ do_cmd() {
 
 do_cmd libtoolize --force --copy
 
-do_cmd aclocal
+do_cmd aclocal ${ACLOCAL_FLAGS}
 
 do_cmd autoheader