1 /* $Id: tif_swab.c,v 1.14 2016-09-04 21:32:56 erouault 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
TIFFSwabShort(uint16 * wp)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
TIFFSwabLong(uint32 * lp)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
TIFFSwabLong8(uint64 * lp)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
TIFFSwabArrayOfShort(register uint16 * wp,tmsize_t n)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
TIFFSwabArrayOfTriples(register uint8 * tp,tmsize_t n)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
TIFFSwabArrayOfLong(register uint32 * lp,tmsize_t n)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
TIFFSwabArrayOfLong8(register uint64 * lp,tmsize_t n)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
TIFFSwabFloat(float * fp)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
TIFFSwabArrayOfFloat(register float * fp,tmsize_t n)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
TIFFSwabDouble(double * dp)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
TIFFSwabArrayOfDouble(double * dp,tmsize_t n)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*
TIFFGetBitRevTable(int reversed)280 TIFFGetBitRevTable(int reversed)
281 {
282 return (reversed ? TIFFBitRevTable : TIFFNoBitRevTable);
283 }
284
285 void
TIFFReverseBits(uint8 * cp,tmsize_t n)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];
301 cp++;
302 }
303 }
304
305 /* vim: set ts=8 sts=8 sw=8 noet: */
306 /*
307 * Local Variables:
308 * mode: c
309 * c-basic-offset: 8
310 * fill-column: 78
311 * End:
312 */
313