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package com.jsoniter.extra;
import com.jsoniter.JsonIterator;
import com.jsoniter.spi.Slice;
import com.jsoniter.output.JsonStream;
import java.io.IOException;
import java.util.Arrays;
/** A very fast and memory efficient class to encode and decode to and from BASE64 in full accordance
* with RFC 2045.<br><br>
* On Windows XP sp1 with 1.4.2_04 and later ;), this encoder and decoder is about 10 times faster
* on small arrays (10 - 1000 bytes) and 2-3 times as fast on larger arrays (10000 - 1000000 bytes)
* compared to <code>sun.misc.Encoder()/Decoder()</code>.<br><br>
*
* On byte arrays the encoder is about 20% faster than Jakarta Commons Base64 Codec for encode and
* about 50% faster for decoding large arrays. This implementation is about twice as fast on very small
* arrays (< 30 bytes). If source/destination is a <code>String</code> this
* version is about three times as fast due to the fact that the Commons Codec result has to be recoded
* to a <code>String</code> from <code>byte[]</code>, which is very expensive.<br><br>
*
* This encode/decode algorithm doesn't create any temporary arrays as many other codecs do, it only
* allocates the resulting array. This produces less garbage and it is possible to handle arrays twice
* as large as algorithms that create a temporary array. (E.g. Jakarta Commons Codec). It is unknown
* whether Sun's <code>sun.misc.Encoder()/Decoder()</code> produce temporary arrays but since performance
* is quite low it probably does.<br><br>
*
* The encoder produces the same output as the Sun one except that the Sun's encoder appends
* a trailing line separator if the last character isn't a pad. Unclear why but it only adds to the
* length and is probably a side effect. Both are in conformance with RFC 2045 though.<br>
* Commons codec seem to always att a trailing line separator.<br><br>
*
* <b>Note!</b>
* The encode/decode method pairs (types) come in three versions with the <b>exact</b> same algorithm and
* thus a lot of code redundancy. This is to not create any temporary arrays for transcoding to/from different
* format types. The methods not used can simply be commented out.<br><br>
*
* There is also a "fast" version of all decode methods that works the same way as the normal ones, but
* har a few demands on the decoded input. Normally though, these fast verions should be used if the source if
* the input is known and it hasn't bee tampered with.<br><br>
*
* If you find the code useful or you find a bug, please send me a note at base64 @ miginfocom . com.
*
* Licence (BSD):
* ==============
*
* Copyright (c) 2004, Mikael Grev, MiG InfoCom AB. (base64 @ miginfocom . com)
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice, this list
* of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice, this
* list of conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution.
* Neither the name of the MiG InfoCom AB nor the names of its contributors may be
* used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* @version 2.2
* @author Mikael Grev
* Date: 2004-aug-02
* Time: 11:31:11
*/
abstract class Base64 {
private static final char[] CA = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/".toCharArray();
static final byte[] BA;
static final int[] IA = new int[256];
static {
Arrays.fill(IA, -1);
for (int i = 0, iS = CA.length; i < iS; i++) {
IA[CA[i]] = i;
}
IA['='] = 0;
BA = new byte[CA.length];
for (int i = 0; i < CA.length; i++) {
BA[i] = (byte)CA[i];
}
}
static int encodeToChar(byte[] sArr, char[] dArr, final int start) {
final int sLen = sArr.length;
final int eLen = (sLen / 3) * 3; // Length of even 24-bits.
final int dLen = ((sLen - 1) / 3 + 1) << 2; // Returned character count
// Encode even 24-bits
for (int s = 0, d = start; s < eLen;) {
// Copy next three bytes into lower 24 bits of int, paying attension to sign.
int i = (sArr[s++] & 0xff) << 16 | (sArr[s++] & 0xff) << 8 | (sArr[s++] & 0xff);
// Encode the int into four chars
dArr[d++] = CA[(i >>> 18) & 0x3f];
dArr[d++] = CA[(i >>> 12) & 0x3f];
dArr[d++] = CA[(i >>> 6) & 0x3f];
dArr[d++] = CA[i & 0x3f];
}
// Pad and encode last bits if source isn't even 24 bits.
int left = sLen - eLen; // 0 - 2.
if (left > 0) {
// Prepare the int
int i = ((sArr[eLen] & 0xff) << 10) | (left == 2 ? ((sArr[sLen - 1] & 0xff) << 2) : 0);
// Set last four chars
dArr[start + dLen - 4] = CA[i >> 12];
dArr[start + dLen - 3] = CA[(i >>> 6) & 0x3f];
dArr[start + dLen - 2] = left == 2 ? CA[i & 0x3f] : '=';
dArr[start + dLen - 1] = '=';
}
return dLen;
}
static int encodeToBytes(byte[] sArr, JsonStream stream) throws IOException {
final int sLen = sArr.length;
final int eLen = (sLen / 3) * 3; // Length of even 24-bits.
final int dLen = ((sLen - 1) / 3 + 1) << 2; // Returned character count
// Encode even 24-bits
for (int s = 0; s < eLen;) {
// Copy next three bytes into lower 24 bits of int, paying attension to sign.
int i = (sArr[s++] & 0xff) << 16 | (sArr[s++] & 0xff) << 8 | (sArr[s++] & 0xff);
// Encode the int into four chars
stream.write(BA[(i >>> 18) & 0x3f], BA[(i >>> 12) & 0x3f], BA[(i >>> 6) & 0x3f], BA[i & 0x3f]);
}
// Pad and encode last bits if source isn't even 24 bits.
int left = sLen - eLen; // 0 - 2.
if (left > 0) {
// Prepare the int
int i = ((sArr[eLen] & 0xff) << 10) | (left == 2 ? ((sArr[sLen - 1] & 0xff) << 2) : 0);
// Set last four chars
stream.write(BA[i >> 12], BA[(i >>> 6) & 0x3f], left == 2 ? BA[i & 0x3f] : (byte)'=', (byte)'=');
}
return dLen;
}
static void encodeLongBits(long bits, JsonStream stream) throws IOException {
int i = (int) bits;
byte b1 = BA[(i >>> 18) & 0x3f];
byte b2 = BA[(i >>> 12) & 0x3f];
byte b3 = BA[(i >>> 6) & 0x3f];
byte b4 = BA[i & 0x3f];
stream.write((byte)'"', b1, b2, b3, b4);
bits = bits >>> 24;
i = (int) bits;
b1 = BA[(i >>> 18) & 0x3f];
b2 = BA[(i >>> 12) & 0x3f];
b3 = BA[(i >>> 6) & 0x3f];
b4 = BA[i & 0x3f];
stream.write(b1, b2, b3, b4);
bits = (bits >>> 24) << 2;
i = (int) bits;
b1 = BA[i >> 12];
b2 = BA[(i >>> 6) & 0x3f];
b3 = BA[i & 0x3f];
stream.write(b1, b2, b3, (byte)'"');
}
static long decodeLongBits(JsonIterator iter) throws IOException {
Slice slice = iter.readStringAsSlice();
if (slice.len() != 11) {
throw iter.reportError("decodeLongBits", "must be 11 bytes for long bits encoded double");
}
byte[] encoded = slice.data();
int sIx = slice.head();
long i = IA[encoded[sIx++]] << 18 | IA[encoded[sIx++]] << 12 | IA[encoded[sIx++]] << 6 | IA[encoded[sIx++]];
long bits = i;
i = IA[encoded[sIx++]] << 18 | IA[encoded[sIx++]] << 12 | IA[encoded[sIx++]] << 6 | IA[encoded[sIx++]];
bits = i << 24 | bits;
i = IA[encoded[sIx++]] << 12 | IA[encoded[sIx++]] << 6 | IA[encoded[sIx]];
bits = i << 46 | bits;
return bits;
}
static int findEnd(final byte[] sArr, final int start) {
for (int i = start; i < sArr.length; i++)
if (IA[sArr[i] & 0xff] < 0)
return i;
return sArr.length;
}
private final static byte[] EMPTY_ARRAY = new byte[0];
static byte[] decodeFast(final byte[] sArr, final int start, final int end) {
// Check special case
int sLen = end - start;
if (sLen == 0)
return EMPTY_ARRAY;
int sIx = start, eIx = end - 1; // Start and end index after trimming.
// Trim illegal chars from start
while (sIx < eIx && IA[sArr[sIx] & 0xff] < 0)
sIx++;
// Trim illegal chars from end
while (eIx > 0 && IA[sArr[eIx] & 0xff] < 0)
eIx--;
// get the padding count (=) (0, 1 or 2)
int pad = sArr[eIx] == '=' ? (sArr[eIx - 1] == '=' ? 2 : 1) : 0; // Count '=' at end.
int cCnt = eIx - sIx + 1; // Content count including possible separators
int sepCnt = sLen > 76 ? (sArr[76] == '\r' ? cCnt / 78 : 0) << 1 : 0;
int len = ((cCnt - sepCnt) * 6 >> 3) - pad; // The number of decoded bytes
byte[] dArr = new byte[len]; // Preallocate byte[] of exact length
// Decode all but the last 0 - 2 bytes.
int d = 0;
for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {
// Assemble three bytes into an int from four "valid" characters.
int i = IA[sArr[sIx++]] << 18 | IA[sArr[sIx++]] << 12 | IA[sArr[sIx++]] << 6 | IA[sArr[sIx++]];
// Add the bytes
dArr[d++] = (byte) (i >> 16);
dArr[d++] = (byte) (i >> 8);
dArr[d++] = (byte) i;
// If line separator, jump over it.
if (sepCnt > 0 && ++cc == 19) {
sIx += 2;
cc = 0;
}
}
if (d < len) {
// Decode last 1-3 bytes (incl '=') into 1-3 bytes
int i = 0;
for (int j = 0; sIx <= eIx - pad; j++)
i |= IA[sArr[sIx++]] << (18 - j * 6);
for (int r = 16; d < len; r -= 8)
dArr[d++] = (byte) (i >> r);
}
return dArr;
}
}