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Diffstat (limited to 'src/lzf_d.c')
| -rw-r--r-- | src/lzf_d.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/src/lzf_d.c b/src/lzf_d.c new file mode 100644 index 0000000..ff32be8 --- /dev/null +++ b/src/lzf_d.c @@ -0,0 +1,191 @@ +/* + * Copyright (c) 2000-2010 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. + * + * 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 ("GPL") version 2 or any later version, + * 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 + +#if USE_REP_MOVSB /* small win on amd, big loss on intel */ +#if (__i386 || __amd64) && __GNUC__ >= 3 +# define lzf_movsb(dst, src, len) \ + asm ("rep movsb" \ + : "=D" (dst), "=S" (src), "=c" (len) \ + : "0" (dst), "1" (src), "2" (len)); +#endif +#endif + +#if defined(__GNUC__) && __GNUC__ >= 7 +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wimplicit-fallthrough" +#endif +size_t +lzf_decompress (const void *const in_data, size_t in_len, + void *out_data, size_t 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; + + while (ip < in_end) + { + unsigned int ctrl; + ctrl = *ip++; + + if (ctrl < (1 << 5)) /* literal run */ + { + ctrl++; + + if (op + ctrl > out_end) + { + SET_ERRNO (E2BIG); + return 0; + } + +#if CHECK_INPUT + if (ip + ctrl > in_end) + { + SET_ERRNO (EINVAL); + return 0; + } +#endif + +#ifdef lzf_movsb + lzf_movsb (op, ip, ctrl); +#else + switch (ctrl) + { + case 32: *op++ = *ip++; case 31: *op++ = *ip++; case 30: *op++ = *ip++; case 29: *op++ = *ip++; + case 28: *op++ = *ip++; case 27: *op++ = *ip++; case 26: *op++ = *ip++; case 25: *op++ = *ip++; + case 24: *op++ = *ip++; case 23: *op++ = *ip++; case 22: *op++ = *ip++; case 21: *op++ = *ip++; + case 20: *op++ = *ip++; case 19: *op++ = *ip++; case 18: *op++ = *ip++; case 17: *op++ = *ip++; + case 16: *op++ = *ip++; case 15: *op++ = *ip++; case 14: *op++ = *ip++; case 13: *op++ = *ip++; + case 12: *op++ = *ip++; case 11: *op++ = *ip++; case 10: *op++ = *ip++; case 9: *op++ = *ip++; + case 8: *op++ = *ip++; case 7: *op++ = *ip++; case 6: *op++ = *ip++; case 5: *op++ = *ip++; + case 4: *op++ = *ip++; case 3: *op++ = *ip++; case 2: *op++ = *ip++; case 1: *op++ = *ip++; + } +#endif + } + else /* back reference */ + { + unsigned int len = ctrl >> 5; + + u8 *ref = op - ((ctrl & 0x1f) << 8) - 1; + +#if CHECK_INPUT + if (ip >= in_end) + { + SET_ERRNO (EINVAL); + return 0; + } +#endif + if (len == 7) + { + len += *ip++; +#if CHECK_INPUT + if (ip >= in_end) + { + SET_ERRNO (EINVAL); + return 0; + } +#endif + } + + ref -= *ip++; + + if (op + len + 2 > out_end) + { + SET_ERRNO (E2BIG); + return 0; + } + + if (ref < (u8 *)out_data) + { + SET_ERRNO (EINVAL); + return 0; + } + +#ifdef lzf_movsb + len += 2; + lzf_movsb (op, ref, len); +#else + switch (len) + { + default: + len += 2; + + if (op >= ref + len) + { + /* disjunct areas */ + memcpy (op, ref, len); + op += len; + } + else + { + /* overlapping, use octte by octte copying */ + do + *op++ = *ref++; + while (--len); + } + + break; + + case 9: *op++ = *ref++; /* fall-thru */ + case 8: *op++ = *ref++; /* fall-thru */ + case 7: *op++ = *ref++; /* fall-thru */ + case 6: *op++ = *ref++; /* fall-thru */ + case 5: *op++ = *ref++; /* fall-thru */ + case 4: *op++ = *ref++; /* fall-thru */ + case 3: *op++ = *ref++; /* fall-thru */ + case 2: *op++ = *ref++; /* fall-thru */ + case 1: *op++ = *ref++; /* fall-thru */ + case 0: *op++ = *ref++; /* two octets more */ + *op++ = *ref++; /* fall-thru */ + } +#endif + } + } + + return op - (u8 *)out_data; +} +#if defined(__GNUC__) && __GNUC__ >= 5 +#pragma GCC diagnostic pop +#endif |