Added rather simplistic build script

This script takes the intended branch, "testing" or "stable", as the single
parameter. It then tries to autodetermine the correct release name, builds
gluon for the corresponding branch and all supported platforms (excluding
x86*), and optionally signs it if an ecdsutils keyfile is found (standard path:
~/.ecdsakey)

build.sh

@@ -0,0 +1,97 @@
+#!/bin/sh
+
+FIRMWARE_URL="http://downloads.bremen.freifunk.net/firmware/"
+LOCAL_SUFFIX="bremen"
+GLUON_DIR="gluon/"
+KEYFILE="$HOME/.ecdsakey"
+
+set -eu
+
+export GLUON_SITEDIR="$(dirname "$(readlink -f "$0")")"
+
+get_gluon_tag() {
+  if ! git --git-dir="${GLUON_DIR}/.git" describe --exact-match; then
+    echo 'The gluon tree is not checked out at a tag.'
+    echo 'Please use `git checkout <tagname>` to use an official gluon release'
+    echo 'or build it manually. Only with at a tag we can autogenerate the'
+    echo 'release string!'
+    exit 1
+  fi
+}
+
+get_last_release() {
+  branch="$1"
+  wget -q -O- "${FIRMWARE_URL}/${branch}/sysupgrade/${branch}.manifest" | \
+    awk 'parse == 1 { print $2; exit } /^$/ { parse=1 }'
+}
+
+is_based_on() {
+  [ "${1#$2}" != "${1}" ]
+  return $?
+}
+
+extract_local_version() {
+  local_version_tmp="${1#*+${LOCAL_SUFFIX}}"
+  local_version="${local_version_tmp%~testing}"
+}
+
+if [ "$#" != 1 ]; then
+  cat <<USAGE
+Usage: $(basename $0) <branch>
+
+This script takes the intended branch, "testing" or "stable", as the single
+parameter. It then tries to autodetermine the correct release name, builds
+gluon for the corresponding branch and all supported platforms (excluding
+x86*), and optionally signs it if an ecdsutils keyfile is found (standard path:
+~/.ecdsakey)
+USAGE
+  exit 1
+fi
+
+branch="$1"
+case "$branch" in
+  testing|stable)
+    gluon_tag="$(get_gluon_tag)"
+    # remove prefixed "v"
+    gluon_tag="${gluon_tag#v}"
+    echo "Building Gluon ${gluon_tag} as ${branch}"
+    last_release_testing="$(get_last_release testing)"
+    last_release_stable="$(get_last_release stable)"
+    echo "Last release in branch testing was ${last_release_testing}"
+    if is_based_on "$last_release_testing" "$gluon_tag"; then
+      local_version="$(extract_local_version "$last_release_testing")"
+      if [ "$branch" != "stable" ]; then
+        local_version="$(($local_version + 1))"
+      fi
+    elif [ "$branch" = "stable" ] && is_based_on "$last_release_stable" "$gluon_tag"; then
+      local_version="$(extract_local_version "$last_release_stable")"
+      local_version="$(($local_version + 1))"
+    else
+      # new gluon version => reset local version number
+      local_version=1
+    fi
+    if [ "$branch" = "testing" ]; then
+      local_version="${local_version}~testing"
+    fi
+    auto_determined_release="${gluon_tag}+${LOCAL_SUFFIX}${local_version}"
+    read -p "Release name for this build [default: ${auto_determined_release}]: " GLUON_RELEASE
+    export GLUON_RELEASE="${GLUON_RELEASE:-$auto_determined_release}"
+    export GLUON_BRANCH="$branch"
+    ;;
+  *)
+    echo "Branch not supported yet!"
+    exit 1
+    ;;
+esac
+
+cd "$GLUON_DIR"
+make update
+for target in ar71xx-generic ar71xx-nand mpc85xx-generic; do
+  make clean GLUON_TARGET="$target"
+  make -j5 GLUON_TARGET="$target"
+done
+make manifest
+cd ..
+if [ -n "$KEYFILE" -a -r "$KEYFILE" ]; then
+	"${GLUON_DIR}/contrib/sign.sh" "$KEYFILE" "${GLUON_DIR}/images/sysupgrade/${GLUON_BRANCH}.manifest"
+fi