pcompress/bsdiff/bscommon.h
Moinak Ghosh e788eb43b8 Implement Delta Encoding based on modified bsdiff.
Change to more accurate Sketch value computation approach.
2012-07-19 21:41:07 +05:30

132 lines
3.5 KiB
C

/*-
* Copyright 2012 Moinak Ghosh
* All rights reserved
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted providing 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 AUTHOR ``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 AUTHOR 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 is a part of Pcompress, a chunked parallel multi-
* algorithm lossless compression and decompression program.
*
* Copyright (C) 2012 Moinak Ghosh. All rights reserved.
* Use is subject to license terms.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 3 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
* Lesser General Public License for more details.
*
* moinakg@belenix.org, http://moinakg.wordpress.com/
*
*/
#ifndef _BS_COMMON_
#define _BS_COMMON_
#include <stdio.h>
#include <utils.h>
// Simple stream I/O to buffer
typedef struct {
uchar_t *buf;
bsize_t pos;
bsize_t buflen;
} bufio_t;
static int
BUFOPEN(bufio_t *bio, uchar_t *buf, bsize_t len)
{
bio->buf = buf; bio->pos = 0; bio->buflen = len;
return (0);
}
static bsize_t
BUFWRITE(bufio_t *bio, uchar_t *buf, bsize_t len)
{
if (bio->pos + len < bio->buflen) {
memcpy(bio->buf + bio->pos, buf, len);
bio->pos += len;
return (len);
} else {
return (-1);
}
}
static bsize_t
BUFREAD(bufio_t *bio, uchar_t *buf, bsize_t len)
{
bsize_t actual;
int i;
actual = len;
if (bio->pos + len > bio->buflen) {
actual = bio->buflen - bio->pos;
}
if (actual == 0) return (0);
memcpy(buf, bio->buf + bio->pos, actual);
bio->pos += actual;
return (actual);
}
static bsize_t
BUFTELL(bufio_t *bio)
{
return (bio->pos);
}
static void *
BUFPTR(bufio_t *bio)
{
return (bio->buf + bio->pos);
}
static int
BUFSEEK(bufio_t *bio, bsize_t pos, int typ)
{
if (typ == SEEK_SET) {
bio->pos = pos;
} else if (typ == SEEK_CUR) {
bio->pos += pos;
} else {
if (pos > 0) {
fprintf(stderr, "Cannot seek beyond buffer end.\n");
return (-1);
} else {
bio->pos = bio->buflen + pos;
}
}
return (0);
}
extern int zero_rle_encode(const void *const ibuf, const unsigned int ilen,
void *obuf, unsigned int *const olen);
extern int zero_rle_decode(const void* ibuf, unsigned int ilen,
void* obuf, unsigned int *olen);
#endif