/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
/* JOrbis
* Copyright (C) 2000 ymnk, JCraft,Inc.
*
* Written by: 2000 ymnk<ymnk@jcraft.com>
*
* Many thanks to
* Monty <monty@xiph.org> and
* The XIPHOPHORUS Company http://www.xiph.org/ .
* JOrbis has been based on their awesome works, Vorbis codec.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public License
* as published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
package com.jcraft.jogg;
public class Buffer {
private static final int BUFFER_INCREMENT = 256;
private static final int[] mask = {0x00000000, 0x00000001, 0x00000003,
0x00000007, 0x0000000f, 0x0000001f, 0x0000003f, 0x0000007f, 0x000000ff,
0x000001ff, 0x000003ff, 0x000007ff, 0x00000fff, 0x00001fff, 0x00003fff,
0x00007fff, 0x0000ffff, 0x0001ffff, 0x0003ffff, 0x0007ffff, 0x000fffff,
0x001fffff, 0x003fffff, 0x007fffff, 0x00ffffff, 0x01ffffff, 0x03ffffff,
0x07ffffff, 0x0fffffff, 0x1fffffff, 0x3fffffff, 0x7fffffff, 0xffffffff};
int ptr = 0;
byte[] buffer = null;
int endbit = 0;
int endbyte = 0;
int storage = 0;
public void writeinit() {
buffer = new byte[BUFFER_INCREMENT];
ptr = 0;
buffer[0] = (byte) '\0';
storage = BUFFER_INCREMENT;
}
public void write(byte[] s) {
for (int i = 0; i < s.length; i++) {
byte value = s[i];
if (value == 0)
break;
write(value, 8);
}
}
public void read(byte[] s, int bytes) {
int i = 0;
while (bytes-- != 0) {
s[i++] = (byte) (read(8));
}
}
void reset() {
ptr = 0;
buffer[0] = (byte) '\0';
endbit = endbyte = 0;
}
public void writeclear() {
buffer = null;
}
public void readinit(byte[] buf, int bytes) {
readinit(buf, 0, bytes);
}
public void readinit(byte[] buf, int start, int bytes) {
ptr = start;
buffer = buf;
endbit = endbyte = 0;
storage = bytes;
}
public void write(int value, int bits) {
if (endbyte + 4 >= storage) {
byte[] foo = new byte[storage + BUFFER_INCREMENT];
System.arraycopy(buffer, 0, foo, 0, storage);
buffer = foo;
storage += BUFFER_INCREMENT;
}
value &= mask[bits];
bits += endbit;
buffer[ptr] |= (byte) (value << endbit);
if (bits >= 8) {
buffer[ptr + 1] = (byte) (value >>> (8 - endbit));
if (bits >= 16) {
buffer[ptr + 2] = (byte) (value >>> (16 - endbit));
if (bits >= 24) {
buffer[ptr + 3] = (byte) (value >>> (24 - endbit));
if (bits >= 32) {
if (endbit > 0)
buffer[ptr + 4] = (byte) (value >>> (32 - endbit));
else
buffer[ptr + 4] = 0;
}
}
}
}
endbyte += bits / 8;
ptr += bits / 8;
endbit = bits & 7;
}
public int look(int bits) {
int ret;
int m = mask[bits];
bits += endbit;
if (endbyte + 4 >= storage) {
if (endbyte + (bits - 1) / 8 >= storage)
return (-1);
}
ret = ((buffer[ptr]) & 0xff) >>> endbit;
if (bits > 8) {
ret |= ((buffer[ptr + 1]) & 0xff) << (8 - endbit);
if (bits > 16) {
ret |= ((buffer[ptr + 2]) & 0xff) << (16 - endbit);
if (bits > 24) {
ret |= ((buffer[ptr + 3]) & 0xff) << (24 - endbit);
if (bits > 32 && endbit != 0) {
ret |= ((buffer[ptr + 4]) & 0xff) << (32 - endbit);
}
}
}
}
return (m & ret);
}
public int look1() {
if (endbyte >= storage)
return (-1);
return ((buffer[ptr] >> endbit) & 1);
}
public void adv(int bits) {
bits += endbit;
ptr += bits / 8;
endbyte += bits / 8;
endbit = bits & 7;
}
public void adv1() {
++endbit;
if (endbit > 7) {
endbit = 0;
ptr++;
endbyte++;
}
}
public int read(int bits) {
int ret;
int m = mask[bits];
bits += endbit;
if (endbyte + 4 >= storage) {
ret = -1;
if (endbyte + (bits - 1) / 8 >= storage) {
ptr += bits / 8;
endbyte += bits / 8;
endbit = bits & 7;
return (ret);
}
}
ret = ((buffer[ptr]) & 0xff) >>> endbit;
if (bits > 8) {
ret |= ((buffer[ptr + 1]) & 0xff) << (8 - endbit);
if (bits > 16) {
ret |= ((buffer[ptr + 2]) & 0xff) << (16 - endbit);
if (bits > 24) {
ret |= ((buffer[ptr + 3]) & 0xff) << (24 - endbit);
if (bits > 32 && endbit != 0) {
ret |= ((buffer[ptr + 4]) & 0xff) << (32 - endbit);
}
}
}
}
ret &= m;
ptr += bits / 8;
endbyte += bits / 8;
endbit = bits & 7;
return (ret);
}
public int readB(int bits) {
int ret;
int m = 32 - bits;
bits += endbit;
if (endbyte + 4 >= storage) {
/* not the main path */
ret = -1;
if (endbyte * 8 + bits > storage * 8) {
ptr += bits / 8;
endbyte += bits / 8;
endbit = bits & 7;
return (ret);
}
}
ret = (buffer[ptr] & 0xff) << (24 + endbit);
if (bits > 8) {
ret |= (buffer[ptr + 1] & 0xff) << (16 + endbit);
if (bits > 16) {
ret |= (buffer[ptr + 2] & 0xff) << (8 + endbit);
if (bits > 24) {
ret |= (buffer[ptr + 3] & 0xff) << (endbit);
if (bits > 32 && (endbit != 0))
ret |= (buffer[ptr + 4] & 0xff) >> (8 - endbit);
}
}
}
ret = (ret >>> (m >> 1)) >>> ((m + 1) >> 1);
ptr += bits / 8;
endbyte += bits / 8;
endbit = bits & 7;
return (ret);
}
public int read1() {
int ret;
if (endbyte >= storage) {
ret = -1;
endbit++;
if (endbit > 7) {
endbit = 0;
ptr++;
endbyte++;
}
return (ret);
}
ret = (buffer[ptr] >> endbit) & 1;
endbit++;
if (endbit > 7) {
endbit = 0;
ptr++;
endbyte++;
}
return (ret);
}
public int bytes() {
return (endbyte + (endbit + 7) / 8);
}
public int bits() {
return (endbyte * 8 + endbit);
}
public byte[] buffer() {
return (buffer);
}
public static int ilog(int v) {
int ret = 0;
while (v > 0) {
ret++;
v >>>= 1;
}
return (ret);
}
public static void report(String in) {
System.err.println(in);
System.exit(1);
}
}