-/*
- * Copyright (C) 2010 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 be.nikiroo.utils.streams;
-
-import java.io.FilterInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-
-/**
- * An InputStream that does Base64 decoding on the data read through
- * it.
- */
-public class Base64InputStream extends FilterInputStream {
- private final Base64.Coder coder;
-
- private static byte[] EMPTY = new byte[0];
-
- private static final int BUFFER_SIZE = 2048;
- private boolean eof;
- private byte[] inputBuffer;
- private int outputStart;
- private int outputEnd;
-
- /**
- * An InputStream that performs Base64 decoding on the data read
- * from the wrapped stream.
- *
- * @param in the InputStream to read the source data from
- */
- public Base64InputStream(InputStream in) {
- this(in, false);
- }
-
- /**
- * Performs Base64 encoding or decoding on the data read from the
- * wrapped InputStream.
- *
- * @param in the InputStream to read the source data from
- * @param flags bit flags for controlling the decoder; see the
- * constants in {@link Base64}
- * @param encode true to encode, false to decode
- *
- * @hide
- */
- public Base64InputStream(InputStream in, boolean encode) {
- super(in);
- eof = false;
- inputBuffer = new byte[BUFFER_SIZE];
- if (encode) {
- coder = new Base64.Encoder(Base64.NO_WRAP, null);
- } else {
- coder = new Base64.Decoder(Base64.NO_WRAP, null);
- }
- coder.output = new byte[coder.maxOutputSize(BUFFER_SIZE)];
- outputStart = 0;
- outputEnd = 0;
- }
-
- public boolean markSupported() {
- return false;
- }
-
- public void mark(int readlimit) {
- throw new UnsupportedOperationException();
- }
-
- public void reset() {
- throw new UnsupportedOperationException();
- }
-
- public void close() throws IOException {
- in.close();
- inputBuffer = null;
- }
-
- public int available() {
- return outputEnd - outputStart;
- }
-
- public long skip(long n) throws IOException {
- if (outputStart >= outputEnd) {
- refill();
- }
- if (outputStart >= outputEnd) {
- return 0;
- }
- long bytes = Math.min(n, outputEnd-outputStart);
- outputStart += bytes;
- return bytes;
- }
-
- public int read() throws IOException {
- if (outputStart >= outputEnd) {
- refill();
- }
- if (outputStart >= outputEnd) {
- return -1;
- } else {
- return coder.output[outputStart++] & 0xff;
- }
- }
-
- public int read(byte[] b, int off, int len) throws IOException {
- if (outputStart >= outputEnd) {
- refill();
- }
- if (outputStart >= outputEnd) {
- return -1;
- }
- int bytes = Math.min(len, outputEnd-outputStart);
- System.arraycopy(coder.output, outputStart, b, off, bytes);
- outputStart += bytes;
- return bytes;
- }
-
- /**
- * Read data from the input stream into inputBuffer, then
- * decode/encode it into the empty coder.output, and reset the
- * outputStart and outputEnd pointers.
- */
- private void refill() throws IOException {
- if (eof) return;
- int bytesRead = in.read(inputBuffer);
- boolean success;
- if (bytesRead == -1) {
- eof = true;
- success = coder.process(EMPTY, 0, 0, true);
- } else {
- success = coder.process(inputBuffer, 0, bytesRead, false);
- }
- if (!success) {
- throw new IOException("bad base-64");
- }
- outputEnd = coder.op;
- outputStart = 0;
- }
-}