1 /* $Id: tif_swab.c,v 1.13 2010-03-10 18:56:49 bfriesen Exp $ */ 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 unsigned char* cp = (unsigned char*) wp; 39 unsigned char t; 40 assert(sizeof(uint16)==2); 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 unsigned char* cp = (unsigned char*) lp; 50 unsigned char t; 51 assert(sizeof(uint32)==4); 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 TIFFSwabLong8 58 void 59 TIFFSwabLong8(uint64* lp) 60 { 61 register unsigned char* cp = (unsigned char*) lp; 62 unsigned char t; 63 assert(sizeof(uint64)==8); 64 t = cp[7]; cp[7] = cp[0]; cp[0] = t; 65 t = cp[6]; cp[6] = cp[1]; cp[1] = t; 66 t = cp[5]; cp[5] = cp[2]; cp[2] = t; 67 t = cp[4]; cp[4] = cp[3]; cp[3] = t; 68 } 69 #endif 70 71 #ifndef TIFFSwabArrayOfShort 72 void 73 TIFFSwabArrayOfShort(register uint16* wp, tmsize_t n) 74 { 75 register unsigned char* cp; 76 register unsigned char t; 77 assert(sizeof(uint16)==2); 78 /* XXX unroll loop some */ 79 while (n-- > 0) { 80 cp = (unsigned char*) wp; 81 t = cp[1]; cp[1] = cp[0]; cp[0] = t; 82 wp++; 83 } 84 } 85 #endif 86 87 #ifndef TIFFSwabArrayOfTriples 88 void 89 TIFFSwabArrayOfTriples(register uint8* tp, tmsize_t n) 90 { 91 unsigned char* cp; 92 unsigned char t; 93 94 /* XXX unroll loop some */ 95 while (n-- > 0) { 96 cp = (unsigned char*) tp; 97 t = cp[2]; cp[2] = cp[0]; cp[0] = t; 98 tp += 3; 99 } 100 } 101 #endif 102 103 #ifndef TIFFSwabArrayOfLong 104 void 105 TIFFSwabArrayOfLong(register uint32* lp, tmsize_t n) 106 { 107 register unsigned char *cp; 108 register unsigned char t; 109 assert(sizeof(uint32)==4); 110 /* XXX unroll loop some */ 111 while (n-- > 0) { 112 cp = (unsigned char *)lp; 113 t = cp[3]; cp[3] = cp[0]; cp[0] = t; 114 t = cp[2]; cp[2] = cp[1]; cp[1] = t; 115 lp++; 116 } 117 } 118 #endif 119 120 #ifndef TIFFSwabArrayOfLong8 121 void 122 TIFFSwabArrayOfLong8(register uint64* lp, tmsize_t n) 123 { 124 register unsigned char *cp; 125 register unsigned char t; 126 assert(sizeof(uint64)==8); 127 /* XXX unroll loop some */ 128 while (n-- > 0) { 129 cp = (unsigned char *)lp; 130 t = cp[7]; cp[7] = cp[0]; cp[0] = t; 131 t = cp[6]; cp[6] = cp[1]; cp[1] = t; 132 t = cp[5]; cp[5] = cp[2]; cp[2] = t; 133 t = cp[4]; cp[4] = cp[3]; cp[3] = t; 134 lp++; 135 } 136 } 137 #endif 138 139 #ifndef TIFFSwabFloat 140 void 141 TIFFSwabFloat(float* fp) 142 { 143 register unsigned char* cp = (unsigned char*) fp; 144 unsigned char t; 145 assert(sizeof(float)==4); 146 t = cp[3]; cp[3] = cp[0]; cp[0] = t; 147 t = cp[2]; cp[2] = cp[1]; cp[1] = t; 148 } 149 #endif 150 151 #ifndef TIFFSwabArrayOfFloat 152 void 153 TIFFSwabArrayOfFloat(register float* fp, tmsize_t n) 154 { 155 register unsigned char *cp; 156 register unsigned char t; 157 assert(sizeof(float)==4); 158 /* XXX unroll loop some */ 159 while (n-- > 0) { 160 cp = (unsigned char *)fp; 161 t = cp[3]; cp[3] = cp[0]; cp[0] = t; 162 t = cp[2]; cp[2] = cp[1]; cp[1] = t; 163 fp++; 164 } 165 } 166 #endif 167 168 #ifndef TIFFSwabDouble 169 void 170 TIFFSwabDouble(double *dp) 171 { 172 register unsigned char* cp = (unsigned char*) dp; 173 unsigned char t; 174 assert(sizeof(double)==8); 175 t = cp[7]; cp[7] = cp[0]; cp[0] = t; 176 t = cp[6]; cp[6] = cp[1]; cp[1] = t; 177 t = cp[5]; cp[5] = cp[2]; cp[2] = t; 178 t = cp[4]; cp[4] = cp[3]; cp[3] = t; 179 } 180 #endif 181 182 #ifndef TIFFSwabArrayOfDouble 183 void 184 TIFFSwabArrayOfDouble(double* dp, tmsize_t n) 185 { 186 register unsigned char *cp; 187 register unsigned char t; 188 assert(sizeof(double)==8); 189 /* XXX unroll loop some */ 190 while (n-- > 0) { 191 cp = (unsigned char *)dp; 192 t = cp[7]; cp[7] = cp[0]; cp[0] = t; 193 t = cp[6]; cp[6] = cp[1]; cp[1] = t; 194 t = cp[5]; cp[5] = cp[2]; cp[2] = t; 195 t = cp[4]; cp[4] = cp[3]; cp[3] = t; 196 dp++; 197 } 198 } 199 #endif 200 201 /* 202 * Bit reversal tables. TIFFBitRevTable[<byte>] gives 203 * the bit reversed value of <byte>. Used in various 204 * places in the library when the FillOrder requires 205 * bit reversal of byte values (e.g. CCITT Fax 3 206 * encoding/decoding). TIFFNoBitRevTable is provided 207 * for algorithms that want an equivalent table that 208 * do not reverse bit values. 209 */ 210 static const unsigned char TIFFBitRevTable[256] = { 211 0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, 212 0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0, 213 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8, 214 0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8, 215 0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4, 216 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4, 217 0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec, 218 0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc, 219 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2, 220 0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2, 221 0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea, 222 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa, 223 0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6, 224 0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6, 225 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee, 226 0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe, 227 0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1, 228 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1, 229 0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, 230 0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9, 231 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5, 232 0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5, 233 0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed, 234 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd, 235 0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3, 236 0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3, 237 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb, 238 0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb, 239 0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7, 240 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7, 241 0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, 242 0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff 243 }; 244 static const unsigned char TIFFNoBitRevTable[256] = { 245 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 246 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f, 247 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 248 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 249 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 250 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 251 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 252 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 253 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 254 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 255 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 256 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 257 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 258 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 259 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 260 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 261 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 262 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 263 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 264 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, 265 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 266 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, 267 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 268 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, 269 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 270 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, 271 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 272 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, 273 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 274 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, 275 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 276 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff, 277 }; 278 279 const unsigned char* 280 TIFFGetBitRevTable(int reversed) 281 { 282 return (reversed ? TIFFBitRevTable : TIFFNoBitRevTable); 283 } 284 285 void 286 TIFFReverseBits(uint8* cp, tmsize_t n) 287 { 288 for (; n > 8; n -= 8) { 289 cp[0] = TIFFBitRevTable[cp[0]]; 290 cp[1] = TIFFBitRevTable[cp[1]]; 291 cp[2] = TIFFBitRevTable[cp[2]]; 292 cp[3] = TIFFBitRevTable[cp[3]]; 293 cp[4] = TIFFBitRevTable[cp[4]]; 294 cp[5] = TIFFBitRevTable[cp[5]]; 295 cp[6] = TIFFBitRevTable[cp[6]]; 296 cp[7] = TIFFBitRevTable[cp[7]]; 297 cp += 8; 298 } 299 while (n-- > 0) 300 *cp = TIFFBitRevTable[*cp], cp++; 301 } 302 303 /* vim: set ts=8 sts=8 sw=8 noet: */ 304 /* 305 * Local Variables: 306 * mode: c 307 * c-basic-offset: 8 308 * fill-column: 78 309 * End: 310 */ 311