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Diffstat (limited to 'src/com/android/tv/license/Licenses.java')
-rw-r--r-- | src/com/android/tv/license/Licenses.java | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/src/com/android/tv/license/Licenses.java b/src/com/android/tv/license/Licenses.java new file mode 100644 index 00000000..4b8a7ffc --- /dev/null +++ b/src/com/android/tv/license/Licenses.java @@ -0,0 +1,122 @@ +/* + * Copyright (C) 2017 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License + */ + +package com.android.tv.license; + +import android.content.Context; +import android.support.annotation.RawRes; + +import com.android.tv.R; +import com.android.tv.common.SoftPreconditions; + +import java.io.ByteArrayOutputStream; +import java.io.IOException; +import java.io.InputStream; +import java.io.UnsupportedEncodingException; +import java.util.ArrayList; +import java.util.Collections; + +/** + * A helper for extracting licenses embedded using + * third_party_licenses.build:third_party_licenses(). + */ +public final class Licenses { + + public static final String TAG = "Licenses"; + public static boolean hasLicenses(Context context) { + return !getTextFromResource( + context.getApplicationContext(), R.raw.third_party_license_metadata, 0, -1) + .isEmpty(); + } + + /** Return the licenses bundled into this app. */ + public static ArrayList<License> getLicenses(Context context) { + return getLicenseListFromMetadata( + getTextFromResource( + context.getApplicationContext(), R.raw.third_party_license_metadata, 0, -1), + ""); + } + + /** + * Returns a list of {@link License}s parsed from a license metadata file. + * + * @param metadata a {@code String} containing the contents of a license metadata file. + * @param filePath a path to a package archive with licenses or empty string for the app package + */ + private static ArrayList<License> getLicenseListFromMetadata(String metadata, String filePath) { + String[] entries = metadata.split("\n"); + ArrayList<License> licenses = new ArrayList<License>(entries.length); + for (String entry : entries) { + int delimiter = entry.indexOf(' '); + String[] licenseLocation = entry.substring(0, delimiter).split(":"); + SoftPreconditions.checkState( + licenseLocation.length == 2 && delimiter > 0, + TAG, + "Invalid license meta-data line:\n" + entry); + long licenseOffset = Long.parseLong(licenseLocation[0]); + int licenseLength = Integer.parseInt(licenseLocation[1]); + licenses.add( + License.create( + entry.substring(delimiter + 1), + licenseOffset, + licenseLength, + filePath)); + } + Collections.sort(licenses); + return licenses; + } + + /** Return the text of a bundled license file. */ + public static String getLicenseText(Context context, License license) { + long offset = license.getLicenseOffset(); + int length = license.getLicenseLength(); + return getTextFromResource(context, R.raw.third_party_licenses, offset, length); + } + + private static String getTextFromResource( + Context context, @RawRes int resourcesIdentifier, long offset, int length) { + InputStream stream = + context.getApplicationContext().getResources().openRawResource(resourcesIdentifier); + return getTextFromInputStream(stream, offset, length); + } + + private static String getTextFromInputStream(InputStream stream, long offset, int length) { + byte[] buffer = new byte[1024]; + ByteArrayOutputStream textArray = new ByteArrayOutputStream(); + + try { + stream.skip(offset); + int bytesRemaining = length > 0 ? length : Integer.MAX_VALUE; + int bytes = 0; + + while (bytesRemaining > 0 + && (bytes = stream.read(buffer, 0, Math.min(bytesRemaining, buffer.length))) + != -1) { + textArray.write(buffer, 0, bytes); + bytesRemaining -= bytes; + } + stream.close(); + } catch (IOException e) { + throw new RuntimeException("Failed to read license or metadata text.", e); + } + try { + return textArray.toString("UTF-8"); + } catch (UnsupportedEncodingException e) { + throw new RuntimeException( + "Unsupported encoding UTF8. This should always be supported.", e); + } + } +} |