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 13900 : TIFFSwabShort(uint16* wp)
37 : {
38 13900 : register unsigned char* cp = (unsigned char*) wp;
39 : unsigned char t;
40 : assert(sizeof(uint16)==2);
41 13900 : t = cp[1]; cp[1] = cp[0]; cp[0] = t;
42 13900 : }
43 : #endif
44 :
45 : #ifndef TIFFSwabLong
46 : void
47 6865 : TIFFSwabLong(uint32* lp)
48 : {
49 6865 : register unsigned char* cp = (unsigned char*) lp;
50 : unsigned char t;
51 : assert(sizeof(uint32)==4);
52 6865 : t = cp[3]; cp[3] = cp[0]; cp[0] = t;
53 6865 : t = cp[2]; cp[2] = cp[1]; cp[1] = t;
54 6865 : }
55 : #endif
56 :
57 : #ifndef TIFFSwabLong8
58 : void
59 228 : TIFFSwabLong8(uint64* lp)
60 : {
61 228 : register unsigned char* cp = (unsigned char*) lp;
62 : unsigned char t;
63 : assert(sizeof(uint64)==8);
64 228 : t = cp[7]; cp[7] = cp[0]; cp[0] = t;
65 228 : t = cp[6]; cp[6] = cp[1]; cp[1] = t;
66 228 : t = cp[5]; cp[5] = cp[2]; cp[2] = t;
67 228 : t = cp[4]; cp[4] = cp[3]; cp[3] = t;
68 228 : }
69 : #endif
70 :
71 : #ifndef TIFFSwabArrayOfShort
72 : void
73 610 : 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 70762 : while (n-- > 0) {
80 69542 : cp = (unsigned char*) wp;
81 69542 : t = cp[1]; cp[1] = cp[0]; cp[0] = t;
82 69542 : wp++;
83 : }
84 610 : }
85 : #endif
86 :
87 : #ifndef TIFFSwabArrayOfTriples
88 : void
89 0 : TIFFSwabArrayOfTriples(register uint8* tp, tmsize_t n)
90 : {
91 : unsigned char* cp;
92 : unsigned char t;
93 :
94 : /* XXX unroll loop some */
95 0 : while (n-- > 0) {
96 0 : cp = (unsigned char*) tp;
97 0 : t = cp[2]; cp[2] = cp[0]; cp[0] = t;
98 0 : tp += 3;
99 : }
100 0 : }
101 : #endif
102 :
103 : #ifndef TIFFSwabArrayOfLong
104 : void
105 205 : 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 398070 : while (n-- > 0) {
112 397660 : cp = (unsigned char *)lp;
113 397660 : t = cp[3]; cp[3] = cp[0]; cp[0] = t;
114 397660 : t = cp[2]; cp[2] = cp[1]; cp[1] = t;
115 397660 : lp++;
116 : }
117 205 : }
118 : #endif
119 :
120 : #ifndef TIFFSwabArrayOfLong8
121 : void
122 115 : 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 800679 : while (n-- > 0) {
129 800449 : cp = (unsigned char *)lp;
130 800449 : t = cp[7]; cp[7] = cp[0]; cp[0] = t;
131 800449 : t = cp[6]; cp[6] = cp[1]; cp[1] = t;
132 800449 : t = cp[5]; cp[5] = cp[2]; cp[2] = t;
133 800449 : t = cp[4]; cp[4] = cp[3]; cp[3] = t;
134 800449 : lp++;
135 : }
136 115 : }
137 : #endif
138 :
139 : #ifndef TIFFSwabFloat
140 : void
141 0 : TIFFSwabFloat(float* fp)
142 : {
143 0 : register unsigned char* cp = (unsigned char*) fp;
144 : unsigned char t;
145 : assert(sizeof(float)==4);
146 0 : t = cp[3]; cp[3] = cp[0]; cp[0] = t;
147 0 : t = cp[2]; cp[2] = cp[1]; cp[1] = t;
148 0 : }
149 : #endif
150 :
151 : #ifndef TIFFSwabArrayOfFloat
152 : void
153 0 : 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 0 : while (n-- > 0) {
160 0 : cp = (unsigned char *)fp;
161 0 : t = cp[3]; cp[3] = cp[0]; cp[0] = t;
162 0 : t = cp[2]; cp[2] = cp[1]; cp[1] = t;
163 0 : fp++;
164 : }
165 0 : }
166 : #endif
167 :
168 : #ifndef TIFFSwabDouble
169 : void
170 0 : TIFFSwabDouble(double *dp)
171 : {
172 0 : register unsigned char* cp = (unsigned char*) dp;
173 : unsigned char t;
174 : assert(sizeof(double)==8);
175 0 : t = cp[7]; cp[7] = cp[0]; cp[0] = t;
176 0 : t = cp[6]; cp[6] = cp[1]; cp[1] = t;
177 0 : t = cp[5]; cp[5] = cp[2]; cp[2] = t;
178 0 : t = cp[4]; cp[4] = cp[3]; cp[3] = t;
179 0 : }
180 : #endif
181 :
182 : #ifndef TIFFSwabArrayOfDouble
183 : void
184 22 : 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 */
190 133 : while (n-- > 0) {
191 89 : cp = (unsigned char *)dp;
192 89 : t = cp[7]; cp[7] = cp[0]; cp[0] = t;
193 89 : t = cp[6]; cp[6] = cp[1]; cp[1] = t;
194 89 : t = cp[5]; cp[5] = cp[2]; cp[2] = t;
195 89 : t = cp[4]; cp[4] = cp[3]; cp[3] = t;
196 89 : dp++;
197 : }
198 22 : }
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 6 : TIFFGetBitRevTable(int reversed)
281 : {
282 6 : return (reversed ? TIFFBitRevTable : TIFFNoBitRevTable);
283 : }
284 :
285 : void
286 0 : TIFFReverseBits(uint8* cp, tmsize_t n)
287 : {
288 0 : for (; n > 8; n -= 8) {
289 0 : cp[0] = TIFFBitRevTable[cp[0]];
290 0 : cp[1] = TIFFBitRevTable[cp[1]];
291 0 : cp[2] = TIFFBitRevTable[cp[2]];
292 0 : cp[3] = TIFFBitRevTable[cp[3]];
293 0 : cp[4] = TIFFBitRevTable[cp[4]];
294 0 : cp[5] = TIFFBitRevTable[cp[5]];
295 0 : cp[6] = TIFFBitRevTable[cp[6]];
296 0 : cp[7] = TIFFBitRevTable[cp[7]];
297 0 : cp += 8;
298 : }
299 0 : while (n-- > 0)
300 0 : *cp = TIFFBitRevTable[*cp], cp++;
301 0 : }
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 : */
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