Shell script to check for Android SDK version.

assert_sdk_version.sh

#!/bin/bash

# Bash script to assert that the current version of the SDK is at least the
# specified version. Prints 'true' to standard out if it's the right version,
# 'false' if it's not.
#
# Typically used like this, in your Makefile:
#
#   ifneq ($(shell $(LOCAL_PATH)/assert_sdk_version.sh "r16"),true)
#     $(error SDK version r16 or greater required)
#   endif
#
# See https://gist.github.com/1961404 for asserting NDK version.
# 
# Copyright 2012, Lookout, Inc. <jtjerno@mylookout.com>

# Converts 'r16' into '16'.
function get_version() {
  echo "$1" | sed s/^r//
}

if [[ -z "$1" ]]; then
  echo "Usage: $0 <required version>" >&2
  echo " For example: $0 r16" >&2
  exit 1
fi

expected_version=$(get_version "$1")

emulator_path="$(which emulator)"
if [ ! -z "$emulator_path" ]; then
  ANDROID_SDK_ROOT="$(dirname "$emulator_path")/.."
elif [ -z "$ANDROID_SDK_ROOT" ]; then
  echo "Could not find location of SDK. Put 'emulator' in \$PATH or set \$ANDROID_SDK_ROOT." >&2
  echo false
  exit 1
fi

source_props="$ANDROID_SDK_ROOT/tools/source.properties"

if [ ! -s "$source_props" ]; then
  echo "Assumed SDK path '$ANDROID_SDK_ROOT', could not find tools/source.properties." >&2
  echo false
  exit 1
fi

# Make sure the data is at least kinda sane.
version=$(grep -i '^Pkg.Revision=' $source_props | cut -f2- -d=)
actual_version=$(get_version "$version")
if [ -z "$version" ] || [ -z "$actual_version" ]; then
  echo "Invalid tools/source.properties: $(cat $source_props)" >&2
  echo false
  exit 1
fi

# Unlike the NDK version, SDK versions seem to always be a number, so
# we're just doing a numerical comparison.
if [[ $actual_version -lt $expected_version ]]; then
  echo "false"
else
  echo "true"
fi