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/* |
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* Copyright (c) 2000-2005 Marc Alexander Lehmann <schmorp@schmorp.de> |
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* |
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* Redistribution and use in source and binary forms, with or without modifica- |
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* tion, are permitted provided that the following conditions are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright notice, |
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* this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* |
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* 3. The name of the author may not be used to endorse or promote products |
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* derived from this software without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- |
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* CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
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* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- |
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* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
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* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
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* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
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* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- |
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* ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
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* OF THE POSSIBILITY OF SUCH DAMAGE. |
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* |
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* Alternatively, the contents of this file may be used under the terms of |
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* the GNU General Public License version 2 (the "GPL"), in which case the |
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* provisions of the GPL are applicable instead of the above. If you wish to |
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* allow the use of your version of this file only under the terms of the |
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* GPL and not to allow others to use your version of this file under the |
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* BSD license, indicate your decision by deleting the provisions above and |
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* replace them with the notice and other provisions required by the GPL. If |
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* you do not delete the provisions above, a recipient may use your version |
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* of this file under either the BSD or the GPL. |
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*/ |
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|
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#include "lzfP.h" |
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|
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#if AVOID_ERRNO |
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# define SET_ERRNO(n) |
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#else |
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# include <errno.h> |
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# define SET_ERRNO(n) errno = (n) |
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#endif |
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|
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#if (__i386 || __amd64) && __GNUC__ >= 3 |
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# define lzf_movsb(dst, src, len) \ |
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asm ("rep movsb" \ |
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: "=D" (dst), "=S" (src), "=c" (len) \ |
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: "0" (dst), "1" (src), "2" (len)); |
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#endif |
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|
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unsigned int |
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lzf_decompress (const void *const in_data, unsigned int in_len, |
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void *out_data, unsigned int out_len) |
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{ |
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u8 const *ip = (const u8 *)in_data; |
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u8 *op = (u8 *)out_data; |
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u8 const *const in_end = ip + in_len; |
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u8 *const out_end = op + out_len; |
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|
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do |
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{ |
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unsigned int ctrl = *ip++; |
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|
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if (ctrl < (1 << 5)) /* literal run */ |
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{ |
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ctrl++; |
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|
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if (op + ctrl > out_end) |
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{ |
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SET_ERRNO (E2BIG); |
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return 0; |
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} |
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|
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#if CHECK_INPUT |
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if (ip + ctrl > in_end) |
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{ |
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SET_ERRNO (EINVAL); |
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return 0; |
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} |
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#endif |
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|
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#ifdef lzf_movsb |
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lzf_movsb (op, ip, ctrl); |
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#else |
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do |
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*op++ = *ip++; |
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while (--ctrl); |
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#endif |
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} |
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else /* back reference */ |
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{ |
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unsigned int len = ctrl >> 5; |
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|
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u8 *ref = op - ((ctrl & 0x1f) << 8) - 1; |
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|
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#if CHECK_INPUT |
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if (ip >= in_end) |
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{ |
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SET_ERRNO (EINVAL); |
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return 0; |
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} |
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#endif |
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if (len == 7) |
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{ |
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len += *ip++; |
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#if CHECK_INPUT |
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if (ip >= in_end) |
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{ |
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SET_ERRNO (EINVAL); |
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return 0; |
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} |
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#endif |
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} |
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|
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ref -= *ip++; |
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|
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if (op + len + 2 > out_end) |
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{ |
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SET_ERRNO (E2BIG); |
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return 0; |
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} |
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|
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if (ref < (u8 *)out_data) |
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{ |
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SET_ERRNO (EINVAL); |
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return 0; |
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} |
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|
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#ifdef lzf_movsb |
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len += 2; |
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lzf_movsb (op, ref, len); |
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#else |
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*op++ = *ref++; |
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*op++ = *ref++; |
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|
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do |
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*op++ = *ref++; |
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while (--len); |
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#endif |
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} |
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} |
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while (ip < in_end); |
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|
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return op - (u8 *)out_data; |
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} |
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|
