Improve autogen.sh.

autogen.sh

@@ -1,4 +1,16 @@
-#! /bin/sh
+#!/bin/sh
+
+srcdir=`dirname $0`
+test -z "$srcdir" && srcdir=.
+
+PROJECT=gstreamer-vaapi
+TEST_TYPE=-d
+FILE=gst-libs
+
+test $TEST_TYPE $FILE || {
+    echo "You must run this script in the top-level $PROJECT directory"
+    exit 1
+}
 
 GTKDOCIZE=`which gtkdocize`
 if test -z $GTKDOCIZE; then
@@ -16,5 +28,12 @@ else
         && mv gtk-doc.temp gtk-doc.make
 fi
 
-autoreconf -v --install
-./configure "$@"
+AUTORECONF=`which autoreconf`
+if test -z $AUTORECONF; then
+    echo "*** No autoreconf found ***"
+    exit 1
+else
+    ACLOCAL="${ACLOCAL-aclocal} $ACLOCAL_FLAGS" autoreconf -v --install || exit $?
+fi
+
+./configure "$@" && echo "Now type 'make' to compile $PROJECT."