| 1 | /* |
| 2 | * Copyright (c) 2000-2007 Marc Alexander Lehmann <schmorp@schmorp.de> |
| 3 | * |
| 4 | * Redistribution and use in source and binary forms, with or without modifica- |
| 5 | * tion, are permitted provided that the following conditions are met: |
| 6 | * |
| 7 | * 1. Redistributions of source code must retain the above copyright notice, |
| 8 | * this list of conditions and the following disclaimer. |
| 9 | * |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * |
| 14 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
| 15 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- |
| 16 | * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO |
| 17 | * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- |
| 18 | * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| 19 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
| 20 | * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| 21 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- |
| 22 | * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| 23 | * OF THE POSSIBILITY OF SUCH DAMAGE. |
| 24 | * |
| 25 | * Alternatively, the contents of this file may be used under the terms of |
| 26 | * the GNU General Public License ("GPL") version 2 or any later version, |
| 27 | * in which case the provisions of the GPL are applicable instead of |
| 28 | * the above. If you wish to allow the use of your version of this file |
| 29 | * only under the terms of the GPL and not to allow others to use your |
| 30 | * version of this file under the BSD license, indicate your decision |
| 31 | * by deleting the provisions above and replace them with the notice |
| 32 | * and other provisions required by the GPL. If you do not delete the |
| 33 | * provisions above, a recipient may use your version of this file under |
| 34 | * either the BSD or the GPL. |
| 35 | */ |
| 36 | |
| 37 | #include "lzfP.h" |
| 38 | |
| 39 | #if AVOID_ERRNO |
| 40 | # define SET_ERRNO(n) |
| 41 | #else |
| 42 | # include <errno.h> |
| 43 | # define SET_ERRNO(n) errno = (n) |
| 44 | #endif |
| 45 | |
| 46 | /* |
| 47 | #if (__i386 || __amd64) && __GNUC__ >= 3 |
| 48 | # define lzf_movsb(dst, src, len) \ |
| 49 | asm ("rep movsb" \ |
| 50 | : "=D" (dst), "=S" (src), "=c" (len) \ |
| 51 | : "0" (dst), "1" (src), "2" (len)); |
| 52 | #endif |
| 53 | */ |
| 54 | |
| 55 | unsigned int |
| 56 | lzf_decompress (const void *const in_data, unsigned int in_len, |
| 57 | void *out_data, unsigned int out_len) |
| 58 | { |
| 59 | u8 const *ip = (const u8 *)in_data; |
| 60 | u8 *op = (u8 *)out_data; |
| 61 | u8 const *const in_end = ip + in_len; |
| 62 | u8 *const out_end = op + out_len; |
| 63 | |
| 64 | do |
| 65 | { |
| 66 | unsigned int ctrl = *ip++; |
| 67 | |
| 68 | if (ctrl < (1 << 5)) /* literal run */ |
| 69 | { |
| 70 | ctrl++; |
| 71 | |
| 72 | if (op + ctrl > out_end) |
| 73 | { |
| 74 | SET_ERRNO (E2BIG); |
| 75 | return 0; |
| 76 | } |
| 77 | |
| 78 | #if CHECK_INPUT |
| 79 | if (ip + ctrl > in_end) |
| 80 | { |
| 81 | SET_ERRNO (EINVAL); |
| 82 | return 0; |
| 83 | } |
| 84 | #endif |
| 85 | |
| 86 | #ifdef lzf_movsb |
| 87 | lzf_movsb (op, ip, ctrl); |
| 88 | #else |
| 89 | do |
| 90 | *op++ = *ip++; |
| 91 | while (--ctrl); |
| 92 | #endif |
| 93 | } |
| 94 | else /* back reference */ |
| 95 | { |
| 96 | unsigned int len = ctrl >> 5; |
| 97 | |
| 98 | u8 *ref = op - ((ctrl & 0x1f) << 8) - 1; |
| 99 | |
| 100 | #if CHECK_INPUT |
| 101 | if (ip >= in_end) |
| 102 | { |
| 103 | SET_ERRNO (EINVAL); |
| 104 | return 0; |
| 105 | } |
| 106 | #endif |
| 107 | if (len == 7) |
| 108 | { |
| 109 | len += *ip++; |
| 110 | #if CHECK_INPUT |
| 111 | if (ip >= in_end) |
| 112 | { |
| 113 | SET_ERRNO (EINVAL); |
| 114 | return 0; |
| 115 | } |
| 116 | #endif |
| 117 | } |
| 118 | |
| 119 | ref -= *ip++; |
| 120 | |
| 121 | if (op + len + 2 > out_end) |
| 122 | { |
| 123 | SET_ERRNO (E2BIG); |
| 124 | return 0; |
| 125 | } |
| 126 | |
| 127 | if (ref < (u8 *)out_data) |
| 128 | { |
| 129 | SET_ERRNO (EINVAL); |
| 130 | return 0; |
| 131 | } |
| 132 | |
| 133 | #ifdef lzf_movsb |
| 134 | len += 2; |
| 135 | lzf_movsb (op, ref, len); |
| 136 | #else |
| 137 | *op++ = *ref++; |
| 138 | *op++ = *ref++; |
| 139 | |
| 140 | do |
| 141 | *op++ = *ref++; |
| 142 | while (--len); |
| 143 | #endif |
| 144 | } |
| 145 | } |
| 146 | while (ip < in_end); |
| 147 | |
| 148 | return op - (u8 *)out_data; |
| 149 | } |
| 150 | |