1 files changed, 26 insertions, 0 deletions
diff --git a/avbuild/version.sh b/avbuild/version.sh
new file mode 100755
index 0000000000..4689627869
--- /dev/null
+++ b/avbuild/version.sh
@@ -0,0 +1,26 @@
+#!/bin/sh
+
+# check for git short hash
+revision=$(cd "$1" && git describe --always 2> /dev/null)
+
+# no revision number found
+test "$revision" || revision=$(cd "$1" && cat RELEASE 2> /dev/null)
+
+# releases extract the version number from the VERSION file
+version=$(cd "$1" && cat VERSION 2> /dev/null)
+test "$version" || version=$revision
+
+test -n "$3" && version=$version-$3
+
+if [ -z "$2" ]; then
+    echo "$version"
+    exit
+fi
+
+NEW_REVISION="#define LIBAV_VERSION \"$version\""
+OLD_REVISION=$(cat "$2" 2> /dev/null)
+
+# Update version.h only on revision changes to avoid spurious rebuilds
+if test "$NEW_REVISION" != "$OLD_REVISION"; then
+    echo "$NEW_REVISION" > "$2"
+fi