openjpeg/indexer_JPIP/cio.c

128 lines
3.2 KiB
C

/*
* Copyright (c) 2001-2002, David Janssens
* Copyright (c) 2003, Yannick Verschueren
* Copyright (c) 2003, Communications and remote sensing Laboratory, Universite catholique de Louvain, Belgium
* 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) {
void cio_write(long long 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;
}