| 1 | /* $Header$ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (c) 1988-1997 Sam Leffler |
| 5 | * Copyright (c) 1991-1997 Silicon Graphics, Inc. |
| 6 | * |
| 7 | * Permission to use, copy, modify, distribute, and sell this software and |
| 8 | * its documentation for any purpose is hereby granted without fee, provided |
| 9 | * that (i) the above copyright notices and this permission notice appear in |
| 10 | * all copies of the software and related documentation, and (ii) the names of |
| 11 | * Sam Leffler and Silicon Graphics may not be used in any advertising or |
| 12 | * publicity relating to the software without the specific, prior written |
| 13 | * permission of Sam Leffler and Silicon Graphics. |
| 14 | * |
| 15 | * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, |
| 16 | * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY |
| 17 | * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. |
| 18 | * |
| 19 | * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR |
| 20 | * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, |
| 21 | * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, |
| 22 | * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF |
| 23 | * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE |
| 24 | * OF THIS SOFTWARE. |
| 25 | */ |
| 26 | |
| 27 | /* |
| 28 | * TIFF Library Bit & Byte Swapping Support. |
| 29 | * |
| 30 | * XXX We assume short = 16-bits and long = 32-bits XXX |
| 31 | */ |
| 32 | #include "tiffiop.h" |
| 33 | |
| 34 | #ifndef TIFFSwabShort |
| 35 | void |
| 36 | TIFFSwabShort(uint16* wp) |
| 37 | { |
| 38 | register u_char* cp = (u_char*) wp; |
| 39 | int t; |
| 40 | |
| 41 | t = cp[1]; cp[1] = cp[0]; cp[0] = t; |
| 42 | } |
| 43 | #endif |
| 44 | |
| 45 | #ifndef TIFFSwabLong |
| 46 | void |
| 47 | TIFFSwabLong(uint32* lp) |
| 48 | { |
| 49 | register u_char* cp = (u_char*) lp; |
| 50 | int t; |
| 51 | |
| 52 | t = cp[3]; cp[3] = cp[0]; cp[0] = t; |
| 53 | t = cp[2]; cp[2] = cp[1]; cp[1] = t; |
| 54 | } |
| 55 | #endif |
| 56 | |
| 57 | #ifndef TIFFSwabArrayOfShort |
| 58 | void |
| 59 | TIFFSwabArrayOfShort(uint16* wp, register u_long n) |
| 60 | { |
| 61 | register u_char* cp; |
| 62 | register int t; |
| 63 | |
| 64 | /* XXX unroll loop some */ |
| 65 | while (n-- > 0) { |
| 66 | cp = (u_char*) wp; |
| 67 | t = cp[1]; cp[1] = cp[0]; cp[0] = t; |
| 68 | wp++; |
| 69 | } |
| 70 | } |
| 71 | #endif |
| 72 | |
| 73 | #ifndef TIFFSwabArrayOfLong |
| 74 | void |
| 75 | TIFFSwabArrayOfLong(register uint32* lp, register u_long n) |
| 76 | { |
| 77 | register unsigned char *cp; |
| 78 | register int t; |
| 79 | |
| 80 | /* XXX unroll loop some */ |
| 81 | while (n-- > 0) { |
| 82 | cp = (unsigned char *)lp; |
| 83 | t = cp[3]; cp[3] = cp[0]; cp[0] = t; |
| 84 | t = cp[2]; cp[2] = cp[1]; cp[1] = t; |
| 85 | lp++; |
| 86 | } |
| 87 | } |
| 88 | #endif |
| 89 | |
| 90 | #ifndef TIFFSwabDouble |
| 91 | void |
| 92 | TIFFSwabDouble(double *dp) |
| 93 | { |
| 94 | register uint32* lp = (uint32*) dp; |
| 95 | uint32 t; |
| 96 | |
| 97 | TIFFSwabArrayOfLong(lp, 2); |
| 98 | t = lp[0]; lp[0] = lp[1]; lp[1] = t; |
| 99 | } |
| 100 | #endif |
| 101 | |
| 102 | #ifndef TIFFSwabArrayOfDouble |
| 103 | void |
| 104 | TIFFSwabArrayOfDouble(double* dp, register u_long n) |
| 105 | { |
| 106 | register uint32* lp = (uint32*) dp; |
| 107 | register uint32 t; |
| 108 | |
| 109 | TIFFSwabArrayOfLong(lp, n + n); |
| 110 | while (n-- > 0) { |
| 111 | t = lp[0]; lp[0] = lp[1]; lp[1] = t; |
| 112 | lp += 2; |
| 113 | } |
| 114 | } |
| 115 | #endif |
| 116 | |
| 117 | /* |
| 118 | * Bit reversal tables. TIFFBitRevTable[<byte>] gives |
| 119 | * the bit reversed value of <byte>. Used in various |
| 120 | * places in the library when the FillOrder requires |
| 121 | * bit reversal of byte values (e.g. CCITT Fax 3 |
| 122 | * encoding/decoding). TIFFNoBitRevTable is provided |
| 123 | * for algorithms that want an equivalent table that |
| 124 | * do not reverse bit values. |
| 125 | */ |
| 126 | static const unsigned char TIFFBitRevTable[256] = { |
| 127 | 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, |
| 128 | 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0, |
| 129 | 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8, |
| 130 | 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8, |
| 131 | 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4, |
| 132 | 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4, |
| 133 | 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec, |
| 134 | 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc, |
| 135 | 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2, |
| 136 | 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2, |
| 137 | 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea, |
| 138 | 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa, |
| 139 | 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6, |
| 140 | 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6, |
| 141 | 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee, |
| 142 | 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe, |
| 143 | 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1, |
| 144 | 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1, |
| 145 | 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, |
| 146 | 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9, |
| 147 | 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5, |
| 148 | 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5, |
| 149 | 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed, |
| 150 | 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd, |
| 151 | 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3, |
| 152 | 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3, |
| 153 | 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb, |
| 154 | 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb, |
| 155 | 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7, |
| 156 | 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7, |
| 157 | 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, |
| 158 | 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff |
| 159 | }; |
| 160 | static const unsigned char TIFFNoBitRevTable[256] = { |
| 161 | 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, |
| 162 | 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, |
| 163 | 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, |
| 164 | 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, |
| 165 | 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, |
| 166 | 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, |
| 167 | 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, |
| 168 | 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, |
| 169 | 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, |
| 170 | 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, |
| 171 | 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, |
| 172 | 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, |
| 173 | 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, |
| 174 | 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, |
| 175 | 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, |
| 176 | 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, |
| 177 | 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, |
| 178 | 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, |
| 179 | 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, |
| 180 | 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, |
| 181 | 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, |
| 182 | 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, |
| 183 | 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, |
| 184 | 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, |
| 185 | 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, |
| 186 | 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, |
| 187 | 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, |
| 188 | 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, |
| 189 | 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, |
| 190 | 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, |
| 191 | 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, |
| 192 | 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, |
| 193 | }; |
| 194 | |
| 195 | const unsigned char* |
| 196 | TIFFGetBitRevTable(int reversed) |
| 197 | { |
| 198 | return (reversed ? TIFFBitRevTable : TIFFNoBitRevTable); |
| 199 | } |
| 200 | |
| 201 | void |
| 202 | TIFFReverseBits(register u_char* cp, register u_long n) |
| 203 | { |
| 204 | for (; n > 8; n -= 8) { |
| 205 | cp[0] = TIFFBitRevTable[cp[0]]; |
| 206 | cp[1] = TIFFBitRevTable[cp[1]]; |
| 207 | cp[2] = TIFFBitRevTable[cp[2]]; |
| 208 | cp[3] = TIFFBitRevTable[cp[3]]; |
| 209 | cp[4] = TIFFBitRevTable[cp[4]]; |
| 210 | cp[5] = TIFFBitRevTable[cp[5]]; |
| 211 | cp[6] = TIFFBitRevTable[cp[6]]; |
| 212 | cp[7] = TIFFBitRevTable[cp[7]]; |
| 213 | cp += 8; |
| 214 | } |
| 215 | while (n-- > 0) |
| 216 | *cp = TIFFBitRevTable[*cp], cp++; |
| 217 | } |