137 lines
3.0 KiB
C
137 lines
3.0 KiB
C
/*
|
|
* Copyright (c) 2001-2002, David Janssens
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. 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.
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include "cio.h"
|
|
#include <setjmp.h>
|
|
|
|
static unsigned char *cio_start, *cio_end, *cio_bp;
|
|
|
|
extern jmp_buf j2k_error;
|
|
|
|
/* <summary> */
|
|
/* Number of bytes written. */
|
|
/* </summary> */
|
|
int cio_numbytes()
|
|
{
|
|
return cio_bp - cio_start;
|
|
}
|
|
|
|
/* <summary> */
|
|
/* Get position in byte stream. */
|
|
/* </summary> */
|
|
int cio_tell()
|
|
{
|
|
return cio_bp - cio_start;
|
|
}
|
|
|
|
/* <summary> */
|
|
/* Set position in byte stream. */
|
|
/* </summary> */
|
|
void cio_seek(int pos)
|
|
{
|
|
cio_bp = cio_start + pos;
|
|
}
|
|
|
|
/* <summary> */
|
|
/* Number of bytes left before the end of the stream. */
|
|
/* </summary> */
|
|
int cio_numbytesleft()
|
|
{
|
|
return cio_end - cio_bp;
|
|
}
|
|
|
|
/* <summary> */
|
|
/* Get pointer to the current position in the stream. */
|
|
/* </summary> */
|
|
unsigned char *cio_getbp()
|
|
{
|
|
return cio_bp;
|
|
}
|
|
|
|
/* <summary> */
|
|
/* Initialize byte IO. */
|
|
/* </summary> */
|
|
void cio_init(unsigned char *bp, int len)
|
|
{
|
|
cio_start = bp;
|
|
cio_end = bp + len;
|
|
cio_bp = bp;
|
|
}
|
|
|
|
/* <summary> */
|
|
/* Write a byte. */
|
|
/* </summary> */
|
|
void cio_byteout(unsigned char v)
|
|
{
|
|
if (cio_bp >= cio_end)
|
|
longjmp(j2k_error, 1);
|
|
*cio_bp++ = v;
|
|
|
|
}
|
|
|
|
/* <summary> */
|
|
/* Read a byte. */
|
|
/* </summary> */
|
|
unsigned char cio_bytein()
|
|
{
|
|
if (cio_bp >= cio_end)
|
|
longjmp(j2k_error, 1);
|
|
return *cio_bp++;
|
|
}
|
|
|
|
/* <summary> */
|
|
/* Write a byte. */
|
|
/* </summary> */
|
|
void cio_write(unsigned int v, int n)
|
|
{
|
|
int i;
|
|
for (i = n - 1; i >= 0; i--) {
|
|
cio_byteout((unsigned char) ((v >> (i << 3)) & 0xff));
|
|
}
|
|
}
|
|
|
|
/* <summary> */
|
|
/* Read some bytes. */
|
|
/* </summary> */
|
|
unsigned int cio_read(int n)
|
|
{
|
|
int i;
|
|
unsigned int v;
|
|
v = 0;
|
|
for (i = n - 1; i >= 0; i--) {
|
|
v += cio_bytein() << (i << 3);
|
|
}
|
|
return v;
|
|
}
|
|
|
|
/* <summary> */
|
|
/* Write some bytes. */
|
|
/* </summary> */
|
|
void cio_skip(int n)
|
|
{
|
|
cio_bp += n;
|
|
}
|