[tracker/direct-access] build: Require Vala 0.9.3 for libtracker-sparql async work

[Martyn James Russell <mr src gnome org>]

commit 8001072b94c76fff7327ade7b9d96f505b1aace1
Author: Martyn Russell <martyn lanedo com>
Date:   Mon Jul 19 11:04:14 2010 +0100

    build: Require Vala 0.9.3 for libtracker-sparql async work

 autogen.sh |   31 ++++++++++++++++++++++++++++---
 1 files changed, 28 insertions(+), 3 deletions(-)
---
diff --git a/autogen.sh b/autogen.sh
index 038c496..6cc6c58 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -1,11 +1,14 @@
 #!/bin/sh
 # Run this to generate all the initial makefiles, etc.
+#
+# NOTE: compare_versions() is stolen from gnome-autogen.sh
 
 srcdir=`dirname $0`
 test -z "$srcdir" && srcdir=.
 
 PKG_NAME="tracker"
 REQUIRED_AUTOMAKE_VERSION=1.9
+REQUIRED_VALA_VERSION=0.9.3
 
 (test -f $srcdir/configure.ac \
   && test -f $srcdir/README) || {
@@ -14,11 +17,33 @@ REQUIRED_AUTOMAKE_VERSION=1.9
     exit 1
 }
 
+# Usage:
+#     compare_versions MIN_VERSION ACTUAL_VERSION
+# returns true if ACTUAL_VERSION >= MIN_VERSION
+compare_versions() {
+    ch_min_version=$1
+    ch_actual_version=$2
+    ch_status=0
+    IFS="${IFS=         }"; ch_save_IFS="$IFS"; IFS="."
+    set $ch_actual_version
+    for ch_min in $ch_min_version; do
+        ch_cur=`echo $1 | sed 's/[^0-9].*$//'`; shift # remove letter suffixes
+        if [ -z "$ch_min" ]; then break; fi
+        if [ -z "$ch_cur" ]; then ch_status=1; break; fi
+        if [ $ch_cur -gt $ch_min ]; then break; fi
+        if [ $ch_cur -lt $ch_min ]; then ch_status=1; break; fi
+    done
+    IFS="$ch_save_IFS"
+    return $ch_status
+}
+
+# Vala version check
 test -z "$VALAC" && VALAC=valac
+VALA_VERSION=`$VALAC --version | cut -d" " -f2`
+echo $VALA_VERSION
 
-if ! $VALAC --version | sed -e 's/^.*\([0-9]\+\.[0-9]\+\)\.[0-9]\+.*$/\1/' | grep -vq '^0\.[0-6]$'
-then
-    echo "**Error**: You must have valac >= 0.7.6 installed to build $PKG_NAME"
+if ! compare_versions $REQUIRED_VALA_VERSION $VALA_VERSION; then
+    echo "**Error**: You must have valac >= $REQUIRED_VALA_VERSION installed to build $PKG_NAME, you have $VALA_VERSION"
     exit 1
 fi