| /* GENERATED SOURCE. DO NOT MODIFY. */ |
| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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. |
| */ |
| |
| /** |
| * @author Alexander Y. Kleymenov |
| */ |
| package com.android.okhttp.okio; |
| |
| import java.io.UnsupportedEncodingException; |
| |
| final class Base64 { |
| private Base64() { |
| } |
| |
| public static byte[] decode(String in) { |
| // Ignore trailing '=' padding and whitespace from the input. |
| int limit = in.length(); |
| for (; limit > 0; limit--) { |
| char c = in.charAt(limit - 1); |
| if (c != '=' && c != '\n' && c != '\r' && c != ' ' && c != '\t') { |
| break; |
| } |
| } |
| |
| // If the input includes whitespace, this output array will be longer than necessary. |
| byte[] out = new byte[(int) (limit * 6L / 8L)]; |
| int outCount = 0; |
| int inCount = 0; |
| |
| int word = 0; |
| for (int pos = 0; pos < limit; pos++) { |
| char c = in.charAt(pos); |
| |
| int bits; |
| if (c >= 'A' && c <= 'Z') { |
| // char ASCII value |
| // A 65 0 |
| // Z 90 25 (ASCII - 65) |
| bits = c - 65; |
| } else if (c >= 'a' && c <= 'z') { |
| // char ASCII value |
| // a 97 26 |
| // z 122 51 (ASCII - 71) |
| bits = c - 71; |
| } else if (c >= '0' && c <= '9') { |
| // char ASCII value |
| // 0 48 52 |
| // 9 57 61 (ASCII + 4) |
| bits = c + 4; |
| } else if (c == '+' || c == '-') { |
| bits = 62; |
| } else if (c == '/' || c == '_') { |
| bits = 63; |
| } else if (c == '\n' || c == '\r' || c == ' ' || c == '\t') { |
| continue; |
| } else { |
| return null; |
| } |
| |
| // Append this char's 6 bits to the word. |
| word = (word << 6) | (byte) bits; |
| |
| // For every 4 chars of input, we accumulate 24 bits of output. Emit 3 bytes. |
| inCount++; |
| if (inCount % 4 == 0) { |
| out[outCount++] = (byte) (word >> 16); |
| out[outCount++] = (byte) (word >> 8); |
| out[outCount++] = (byte) word; |
| } |
| } |
| |
| int lastWordChars = inCount % 4; |
| if (lastWordChars == 1) { |
| // We read 1 char followed by "===". But 6 bits is a truncated byte! Fail. |
| return null; |
| } else if (lastWordChars == 2) { |
| // We read 2 chars followed by "==". Emit 1 byte with 8 of those 12 bits. |
| word = word << 12; |
| out[outCount++] = (byte) (word >> 16); |
| } else if (lastWordChars == 3) { |
| // We read 3 chars, followed by "=". Emit 2 bytes for 16 of those 18 bits. |
| word = word << 6; |
| out[outCount++] = (byte) (word >> 16); |
| out[outCount++] = (byte) (word >> 8); |
| } |
| |
| // If we sized our out array perfectly, we're done. |
| if (outCount == out.length) return out; |
| |
| // Copy the decoded bytes to a new, right-sized array. |
| byte[] prefix = new byte[outCount]; |
| System.arraycopy(out, 0, prefix, 0, outCount); |
| return prefix; |
| } |
| |
| private static final byte[] MAP = new byte[] { |
| 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', |
| 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', |
| 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', |
| '5', '6', '7', '8', '9', '+', '/' |
| }; |
| |
| private static final byte[] URL_MAP = new byte[] { |
| 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', |
| 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', |
| 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', |
| '5', '6', '7', '8', '9', '-', '_' |
| }; |
| |
| public static String encode(byte[] in) { |
| return encode(in, MAP); |
| } |
| |
| public static String encodeUrl(byte[] in) { |
| return encode(in, URL_MAP); |
| } |
| |
| private static String encode(byte[] in, byte[] map) { |
| int length = (in.length + 2) * 4 / 3; |
| byte[] out = new byte[length]; |
| int index = 0, end = in.length - in.length % 3; |
| for (int i = 0; i < end; i += 3) { |
| out[index++] = map[(in[i] & 0xff) >> 2]; |
| out[index++] = map[((in[i] & 0x03) << 4) | ((in[i + 1] & 0xff) >> 4)]; |
| out[index++] = map[((in[i + 1] & 0x0f) << 2) | ((in[i + 2] & 0xff) >> 6)]; |
| out[index++] = map[(in[i + 2] & 0x3f)]; |
| } |
| switch (in.length % 3) { |
| case 1: |
| out[index++] = map[(in[end] & 0xff) >> 2]; |
| out[index++] = map[(in[end] & 0x03) << 4]; |
| out[index++] = '='; |
| out[index++] = '='; |
| break; |
| case 2: |
| out[index++] = map[(in[end] & 0xff) >> 2]; |
| out[index++] = map[((in[end] & 0x03) << 4) | ((in[end + 1] & 0xff) >> 4)]; |
| out[index++] = map[((in[end + 1] & 0x0f) << 2)]; |
| out[index++] = '='; |
| break; |
| } |
| try { |
| return new String(out, 0, index, "US-ASCII"); |
| } catch (UnsupportedEncodingException e) { |
| throw new AssertionError(e); |
| } |
| } |
| } |