Add script for downloading latest build from buildbot jail.

This script is internal only.

BUG=none
TEST=Built and installed image.

Review URL: http://codereview.chromium.org/2819003

Change-Id: I4426a0e939862211a0527de07aefbea74ab0e092

download_latest_image.sh

@@ -0,0 +1,54 @@
+#!/bin/bash
+
+# Copyright (c) 2009 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# Downloads the latest buildbot image and prints the path to it.
+# This only works internally at Google.
+
+# Load common constants.  This should be the first executable line.
+# The path to common.sh should be relative to your script's location.
+. "$(dirname "$0")/common.sh"
+
+get_default_board
+
+DEFINE_string board "$DEFAULT_BOARD" \
+  "The name of the board to check for images."
+DEFINE_boolean incremental "${FLAGS_FALSE}" "Download incremental build"
+
+# Parse command line flags
+FLAGS "$@" || exit 1
+eval set -- "${FLAGS_ARGV}"
+
+# Check on the board that they are trying to set up.
+if [ -z "$FLAGS_board" ] ; then
+  echo "Error: --board required."
+  exit 1
+fi
+
+IMAGES_DIR="${DEFAULT_BUILD_ROOT}/images/${FLAGS_board}"
+
+if [ $FLAGS_board = x86-generic ]; then
+  if [ "$FLAGS_incremental" -eq "$FLAGS_TRUE" ]; then
+    URL_PREFIX="http://codg174.jail.google.com/archive/x86-generic-inc"
+  else
+    URL_PREFIX="http://codg163.jail.google.com/archive/x86-generic-rel"
+  fi
+else
+  echo "Unrecognized board: $FLAGS_board" >&2
+  exit 1
+fi
+
+LATEST_BUILD=$(curl -s $URL_PREFIX/LATEST)
+LATEST_IMAGE_DIR="$IMAGES_DIR/$LATEST_BUILD"
+if [ ! -e $LATEST_IMAGE_DIR/chromiumos_base_image.bin ]; then
+  mkdir -p $LATEST_IMAGE_DIR
+  curl $URL_PREFIX/$LATEST_BUILD/image.zip -o $LATEST_IMAGE_DIR/image.zip \
+      || die "Could not download image.zip"
+  ( cd $LATEST_IMAGE_DIR && unzip -qo image.zip ) \
+      || die "Could not unzip image.zip"
+fi
+
+echo $LATEST_IMAGE_DIR
+exit 0