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/*
* basE91 encoding/decoding routines
*
* Copyright (c) 2000-2006 Joachim Henke
* 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 Joachim Henke nor the names of his 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.
*/
// This file contains a modified version of Jochaim Henke's Base91:
// https://github.com/bwaldvogel/base91/blob/master/src/main/java/de/bwaldvogel/base91/Base91.java
package hivemall.utils.codec;
import hivemall.utils.io.FastByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import javax.annotation.Nonnull;
/**
* BASE91 is an advanced method for encoding binary data as ASCII, i.e., UTF-8 1 byte, characters.
*
* It uses ACSII printable characters expect Backslash (0x5C), Single Quote (0x27), and Double Quote
* (0x22) while the original version of basE91 use Double Quote (0x22) instead of Dash (0x2D) for
* the encoded string.
*/
public final class Base91 {
public static final float WORST_ENCODING_RATIO = 1.2308f;
public static final float BEST_ENCODING_RATIO = 1.1429f;
private static final byte[] ENCODING_TABLE;
private static final byte[] DECODING_TABLE;
private static final int BASE;
static {
String ts = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
+ "!#$%&()*+,-./:;<=>?@[]^_`{|}~";
ENCODING_TABLE = ts.getBytes();
BASE = ENCODING_TABLE.length;
DECODING_TABLE = new byte[256];
for (int i = 0; i < 256; i++) {
DECODING_TABLE[i] = -1;
}
for (int i = 0; i < BASE; i++) {
DECODING_TABLE[ENCODING_TABLE[i]] = (byte) i;
}
}
@Nonnull
public static byte[] encode(@Nonnull final byte[] input) {
return encode(input, 0, input.length);
}
@Nonnull
public static byte[] encode(@Nonnull final byte[] input, final int offset, final int len) {
int estimatedSize = (int) Math.ceil(len * WORST_ENCODING_RATIO);
final FastByteArrayOutputStream output = new FastByteArrayOutputStream(estimatedSize);
try {
encode(input, offset, len, output);
} catch (IOException e) {
throw new IllegalStateException("Failed to convert BINARY to BASE91 string", e);
}
return output.toByteArray();
}
public static void encode(@Nonnull final byte[] input, @Nonnull final OutputStream output)
throws IOException {
encode(input, 0, input.length, output);
}
public static void encode(@Nonnull final byte[] input, final int offset, final int len,
@Nonnull final OutputStream output) throws IOException {
int ebq = 0;
int en = 0;
for (int i = offset; i < len; ++i) {
ebq |= (input[i] & 255) << en;
en += 8;
if (en > 13) {
int ev = ebq & 0x1FFF; // 0001 1111 1111 1111
if (ev > 88) {
ebq >>= 13;
en -= 13;
} else {
ev = ebq & 0x3FFF; // 0011 1111 1111 1111
ebq >>= 14;
en -= 14;
}
output.write(ENCODING_TABLE[ev % BASE]);
output.write(ENCODING_TABLE[ev / BASE]);
}
}
if (en > 0) {
output.write(ENCODING_TABLE[ebq % BASE]);
if (en > 7 || ebq > 90) {
output.write(ENCODING_TABLE[ebq / BASE]);
}
}
}
public static int encode(@Nonnull final byte[] input, final int offset, final int len,
@Nonnull final OutputStream output, @Nonnull final Base91Buf buf) throws IOException {
int ebq = buf.queue;
int en = buf.bits;
int n = 0;
for (int i = offset; i < len; ++i) {
ebq |= (input[i] & 255) << en;
en += 8;
if (en > 13) { /* enough bits in queue */
int ev = ebq & 0x1FFF; // 0001 1111 1111 1111
if (ev > 88) {
ebq >>= 13;
en -= 13;
} else {
ev = ebq & 0x3FFF; // 0011 1111 1111 1111
ebq >>= 14;
en -= 14;
}
output.write(ENCODING_TABLE[ev % BASE]);
output.write(ENCODING_TABLE[ev / BASE]);
n += 2;
}
}
buf.queue = ebq;
buf.bits = en;
return n;
}
public static void encodeEnd(@Nonnull final OutputStream output, @Nonnull final Base91Buf buf)
throws IOException {
int ebq = buf.queue;
int en = buf.bits;
if (en > 0) {
output.write(ENCODING_TABLE[ebq % BASE]);
if (en > 7 || ebq > 90) {
output.write(ENCODING_TABLE[ebq / BASE]);
}
}
buf.clear();
}
public static void encode(@Nonnull final InputStream in, @Nonnull final OutputStream out)
throws IOException {
int ebq = 0;
int en = 0;
int b;
while ((b = in.read()) != -1) {
ebq |= (b & 255) << en;
en += 8;
if (en > 13) {
int ev = ebq & 0x1FFF; // 0001 1111 1111 1111
if (ev > 88) {
ebq >>= 13;
en -= 13;
} else {
ev = ebq & 0x3FFF; // 0011 1111 1111 1111
ebq >>= 14;
en -= 14;
}
out.write(ENCODING_TABLE[ev % BASE]);
out.write(ENCODING_TABLE[ev / BASE]);
}
}
if (en > 0) {
out.write(ENCODING_TABLE[ebq % BASE]);
if (en > 7 || ebq > 90) {
out.write(ENCODING_TABLE[ebq / BASE]);
}
}
}
@Nonnull
public static byte[] decode(@Nonnull final byte[] input) {
return decode(input, 0, input.length);
}
@Nonnull
public static byte[] decode(@Nonnull final byte[] input, final int offset, final int len) {
int expectedSize = Math.round(len / BEST_ENCODING_RATIO);
final FastByteArrayOutputStream output = new FastByteArrayOutputStream(expectedSize);
try {
decode(input, offset, len, output);
} catch (IOException e) {
throw new IllegalStateException("Failed to decode BASE91 binary", e);
}
return output.toByteArray();
}
public static void decode(@Nonnull final byte[] input, @Nonnull final OutputStream output)
throws IOException {
decode(input, 0, input.length, output);
}
public static void decode(@Nonnull final byte[] input, final int offset, final int len,
@Nonnull final OutputStream output) throws IOException {
int dbq = 0;
int dn = 0;
int dv = -1;
for (int i = offset; i < len; ++i) {
if (DECODING_TABLE[input[i]] == -1) {
continue;
}
if (dv == -1) {
dv = DECODING_TABLE[input[i]];
} else {
dv += DECODING_TABLE[input[i]] * BASE;
dbq |= dv << dn;
dn += (dv & 0x1FFF) > 88 ? 13 : 14;
do {
output.write((byte) dbq);
dbq >>= 8;
dn -= 8;
} while (dn >= 8);
dv = -1;
}
}
if (dv != -1) {
output.write((byte) (dbq | dv << dn));
}
}
public static int decode(@Nonnull final byte[] input, final int offset, final int len,
@Nonnull final OutputStream output, @Nonnull final Base91Buf buf) throws IOException {
int dbq = buf.queue;
int dn = buf.bits;
int dv = buf.value;
int n = 0;
for (int i = offset; i < len; ++i) {
if (DECODING_TABLE[input[i]] == -1) {
continue; /* ignore non-alphabet chars */
}
if (dv == -1) {
dv = DECODING_TABLE[input[i]]; /* start next value */
} else {
dv += DECODING_TABLE[input[i]] * BASE;
dbq |= dv << dn;
dn += (dv & 0x1FFF) > 88 ? 13 : 14;
do {
output.write((byte) dbq);
++n;
dbq >>= 8;
dn -= 8;
} while (dn >= 8);
dv = -1; /* mark value complete */
}
}
buf.queue = dbq;
buf.bits = dn;
buf.value = dv;
return n;
}
public static void decodeEnd(@Nonnull final OutputStream output, @Nonnull final Base91Buf buf)
throws IOException {
int dbq = buf.queue;
int dn = buf.bits;
int dv = buf.value;
if (dv != -1) {
output.write((byte) (dbq | dv << dn));
}
buf.clear();
}
public static byte decodeEnd(@Nonnull final Base91Buf buf) throws IOException {
int dv = buf.value;
if (dv == -1) {
throw new IllegalStateException("SHOULD not be called");
}
int dbq = buf.queue;
int dn = buf.bits;
buf.clear();
return (byte) (dbq | dv << dn);
}
public static void decode(@Nonnull final InputStream in, @Nonnull final OutputStream out)
throws IOException {
int dbq = 0;
int dn = 0;
int dv = -1;
int b;
while ((b = in.read()) != -1) {
if (DECODING_TABLE[b] == -1) {
continue;
}
if (dv == -1) {
dv = DECODING_TABLE[b];
} else {
dv += DECODING_TABLE[b] * BASE;
dbq |= dv << dn;
dn += (dv & 0x1FFF) > 88 ? 13 : 14;
do {
out.write((byte) dbq);
dbq >>= 8;
dn -= 8;
} while (dn >= 8);
dv = -1;
}
}
if (dv != -1) {
out.write((byte) (dbq | dv << dn));
}
}
public static final class Base91Buf {
private int queue;
private int bits;
private int value;
public Base91Buf() {
clear();
}
public boolean isEmpty() {
return value == -1;
}
public void clear() {
this.queue = 0;
this.bits = 0;
this.value = -1;
}
}
}
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