raze/polymer/build/src/lzf_d.c

116 lines
3.7 KiB
C

/*
* Copyright (c) 2000-2005 Marc Alexander Lehmann <schmorp@schmorp.de>
*
* Redistribution and use in source and binary forms, with or without modifica-
* tion, 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.
*
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
* CIAL, 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 OTH-
* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License version 2 (the "GPL"), in which case the
* provisions of the GPL are applicable instead of the above. If you wish to
* allow the use of your version of this file only under the terms of the
* GPL and not to allow others to use your version of this file under the
* BSD license, indicate your decision by deleting the provisions above and
* replace them with the notice and other provisions required by the GPL. If
* you do not delete the provisions above, a recipient may use your version
* of this file under either the BSD or the GPL.
*/
#include "lzfP.h"
#if AVOID_ERRNO
# define SET_ERRNO(n)
#else
# include <errno.h>
# define SET_ERRNO(n) errno = (n)
#endif
unsigned int
lzf_decompress(const void *const in_data, unsigned int in_len,
void *out_data, unsigned int out_len)
{
u8 const *ip = (const u8 *)in_data;
u8 *op = (u8 *)out_data;
u8 const *const in_end = ip + in_len;
u8 *const out_end = op + out_len;
do
{
unsigned int ctrl = *ip++;
if (ctrl < (1 << 5)) /* literal run */
{
ctrl++;
if (op + ctrl > out_end)
{
SET_ERRNO(E2BIG);
return 0;
}
#if USE_MEMCPY
memcpy(op, ip, ctrl);
op += ctrl;
ip += ctrl;
#else
do
*op++ = *ip++;
while (--ctrl);
#endif
}
else /* back reference */
{
unsigned int len = ctrl >> 5;
u8 *ref = op - ((ctrl & 0x1f) << 8) - 1;
if (len == 7)
len += *ip++;
ref -= *ip++;
if (op + len + 2 > out_end)
{
SET_ERRNO(E2BIG);
return 0;
}
if (ref < (u8 *)out_data)
{
SET_ERRNO(EINVAL);
return 0;
}
*op++ = *ref++;
*op++ = *ref++;
do
*op++ = *ref++;
while (--len);
}
}
while (op < out_end && ip < in_end);
return op - (u8 *)out_data;
}