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(crc-mktab): now requires str.c.
[mLib] / bits.h
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6b033bc4 1/* -*-c-*-
2 *
1f175471 3 * $Id: bits.h,v 1.8 2000/10/08 11:06:30 mdw Exp $
6b033bc4 4 *
5 * Portable bit-level manipulation macros
6 *
7 * (c) 1998 Straylight/Edgeware
8 */
9
10/*----- Licensing notice --------------------------------------------------*
11 *
12 * This file is part of the mLib utilities library.
13 *
14 * mLib is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
18 *
19 * mLib is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
23 *
24 * You should have received a copy of the GNU Library General Public
25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
27 * MA 02111-1307, USA.
28 */
29
30/*----- Revision history --------------------------------------------------*
31 *
32 * $Log: bits.h,v $
1f175471 33 * Revision 1.8 2000/10/08 11:06:30 mdw
34 * Shut later versions of GCC up about use of @long long@.
35 *
3b7cea93 36 * Revision 1.7 2000/07/22 09:48:26 mdw
37 * Added macros for reading 64-bit values.
38 *
a6f4a484 39 * Revision 1.6 2000/07/16 12:28:28 mdw
40 * Add 64-bit support, with faked arithmetic on 32-bit hosts.
41 *
6a0129ea 42 * Revision 1.5 2000/06/17 10:36:06 mdw
43 * Support for 24-bit types.
44 *
c6e0eaf0 45 * Revision 1.4 1999/12/10 23:42:04 mdw
46 * Change header file guard names.
47 *
0d4e268a 48 * Revision 1.3 1999/06/20 23:31:52 mdw
49 * More portability enhancements.
50 *
bc9f60b6 51 * Revision 1.2 1999/06/17 00:12:46 mdw
52 * Improve portability for shift and rotate macros.
53 *
6b033bc4 54 * Revision 1.1 1999/06/01 09:46:19 mdw
55 * New addition: bit manipulation macros.
56 *
57 */
58
c6e0eaf0 59#ifndef MLIB_BITS_H
60#define MLIB_BITS_H
6b033bc4 61
62#ifdef __cplusplus
63 extern "C" {
64#endif
65
66/*----- Header files ------------------------------------------------------*/
67
68#include <limits.h>
69#include <stddef.h>
a6f4a484 70#if __STDC_VERSION__ >= 199900l
71# include <stdint.h>
72#endif
6b033bc4 73
74/*----- Decide on some types ----------------------------------------------*/
75
1f175471 76/* --- Make GNU C shut up --- */
77
78#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 91)
79# define MLIB_BITS_EXTENSION __extension__
80#else
81# define MLIB_BITS_EXTENSION
82#endif
83
6b033bc4 84/* --- Decide on a 32-bit type --- *
85 *
86 * I want a type which is capable of expressing 32-bit numbers. Because some
87 * implementations have 64-bit @long@s (infinitely preferable to the abortion
88 * that is @long long@), using @unsigned long@ regardless is wasteful. So,
89 * if @int@ appears to be good enough, then I'll go with that.
90 */
91
92#if UINT_MAX >= 0xffffffffu
93 typedef unsigned int uint32;
94#else
95 typedef unsigned long uint32;
96#endif
97
a6f4a484 98/* --- Decide on a 64-bit type --- *
99 *
100 * The test is quite subtle. Think about it. Note that (at least on my
101 * machine), the 32-bit macros are *much* faster than GCC's @long long@
102 * support.
103 */
104
105#if defined(ULONG_LONG_MAX) && !defined(ULLONG_MAX)
106# define ULLONG_MAX ULONG_LONG_MAX
107#endif
108
109#if UINT_MAX >> 31 > 0xffffffff
1f175471 110# define HAVE_UINT64
111 typedef unsigned int uint64;
a6f4a484 112#elif ULONG_MAX >> 31 > 0xffffffff
1f175471 113# define HAVE_UINT64
114 typedef unsigned long uint64;
a6f4a484 115#elif defined(ULLONG_MAX)
1f175471 116# define HAVE_UINT64
117 MLIB_BITS_EXTENSION typedef unsigned long long uint64;
a6f4a484 118#endif
119
120#ifdef DEBUG64
121# undef HAVE_UINT64
122#endif
123
124#ifdef HAVE_UINT64
125 typedef struct { uint64 i; } kludge64;
126#else
127 typedef struct { uint32 hi, lo; } kludge64;
128#endif
129
6a0129ea 130/* --- Decide on a 24-bit type --- */
131
132#if UINT_MAX >= 0x00ffffffu
133 typedef unsigned int uint24;
134#else
135 typedef unsigned long uint24;
136#endif
137
6b033bc4 138/* --- Decide on 16-bit and 8-bit types --- *
139 *
140 * This is more for brevity than anything else.
141 */
142
143typedef unsigned short uint16;
144typedef unsigned char octet;
145
146/* --- WARNING! --- *
147 *
148 * Never lose sight of the fact that the above types may be wider than the
149 * names suggest. Some architectures have 32-bit @short@s for example.
150 */
151
152/*----- Macros ------------------------------------------------------------*/
153
154/* --- Useful masks --- */
155
156#define MASK8 0xffu
157#define MASK16 0xffffu
6a0129ea 158#define MASK24 0xffffffu
6b033bc4 159#define MASK32 0xffffffffu
160
a6f4a484 161#ifdef HAVE_UINT64
1f175471 162# define MASK64 MLIB_BITS_EXTENSION 0xffffffffffffffffu
a6f4a484 163#endif
164
6b033bc4 165/* --- Type coercions --- */
166
167#define U8(x) ((octet)((x) & MASK8))
168#define U16(x) ((uint16)((x) & MASK16))
6a0129ea 169#define U24(x) ((uint24)((x) & MASK24))
6b033bc4 170#define U32(x) ((uint32)((x) & MASK32))
171
a6f4a484 172#ifdef HAVE_UINT64
173# define U64(x) ((uint64)(x) & MASK64)
174# define U64_(d, x) ((d).i = U64(x).i)
175#else
176# define U64_(d, x) ((d).hi = U32((x).hi), (d).lo = U32((x).lo))
177#endif
178
6b033bc4 179/* --- Safe shifting macros --- */
180
bc9f60b6 181#define LSL8(v, s) U8(U8(v) << ((s) & 7u))
182#define LSR8(v, s) U8(U8(v) >> ((s) & 7u))
183#define LSL16(v, s) U16(U16(v) << ((s) & 15u))
184#define LSR16(v, s) U16(U16(v) >> ((s) & 15u))
6a0129ea 185#define LSL24(v, s) U24(U24(v) << ((s) % 24u))
186#define LSR24(v, s) U24(U24(v) >> ((s) % 24u))
bc9f60b6 187#define LSL32(v, s) U32(U32(v) << ((s) & 31u))
188#define LSR32(v, s) U32(U32(v) >> ((s) & 31u))
6b033bc4 189
a6f4a484 190#ifdef HAVE_UINT64
191# define LSL64(v, s) U64(U64(v) << ((s) & 63u))
192# define LSR64(v, s) U64(U64(v) >> ((s) & 63u))
193# define LSL64_(d, v, s) ((d).i = LSL64((v).i, (s)))
194# define LSR64_(d, v, s) ((d).i = LSR64((v).i, (s)))
195#else
196# define LSL64_(d, v, s) do { \
197 unsigned _s = (s) & 63u; \
198 uint32 _l = (v).lo, _h = (v).hi; \
199 kludge64 *_d = &(d); \
200 if (_s >= 32) { \
201 _d->hi = LSL32(_l, _s - 32u); \
202 _d->lo = 0; \
203 } else if (!_s) { \
204 _d->lo = _l; \
205 _d->hi = _h; \
206 } else { \
207 _d->hi = LSL32(_h, _s) | LSR32(_l, 32u - _s); \
208 _d->lo = LSL32(_l, _s); \
209 } \
210 } while (0)
211# define LSR64_(d, v, s) do { \
212 unsigned _s = (s) & 63u; \
213 uint32 _l = (v).lo, _h = (v).hi; \
214 kludge64 *_d = &(d); \
215 if (_s >= 32) { \
216 _d->lo = LSR32(_h, _s - 32u); \
217 _d->hi = 0; \
218 } else if (!_s) { \
219 _d->lo = _l; \
220 _d->hi = _h; \
221 } else { \
222 _d->lo = LSR32(_l, _s) | LSL32(_h, 32u - _s); \
223 _d->hi = LSR32(_h, _s); \
224 } \
225 } while (0)
226#endif
227
6b033bc4 228/* --- Rotation macros --- */
229
bc9f60b6 230#define ROL8(v, s) (LSL8((v), (s)) | (LSR8((v), 8u - (s))))
231#define ROR8(v, s) (LSR8((v), (s)) | (LSL8((v), 8u - (s))))
232#define ROL16(v, s) (LSL16((v), (s)) | (LSR16((v), 16u - (s))))
233#define ROR16(v, s) (LSR16((v), (s)) | (LSL16((v), 16u - (s))))
6a0129ea 234#define ROL24(v, s) (LSL24((v), (s)) | (LSR24((v), 24u - (s))))
235#define ROR24(v, s) (LSR24((v), (s)) | (LSL24((v), 24u - (s))))
bc9f60b6 236#define ROL32(v, s) (LSL32((v), (s)) | (LSR32((v), 32u - (s))))
237#define ROR32(v, s) (LSR32((v), (s)) | (LSL32((v), 32u - (s))))
6b033bc4 238
a6f4a484 239#ifdef HAVE_UINT64
240# define ROL64(v, s) (LSL64((v), (s)) | (LSR64((v), 64u - (s))))
241# define ROR64(v, s) (LSR64((v), (s)) | (LSL64((v), 64u - (s))))
242# define ROL64_(d, v, s) ((d).i = ROL64((v).i, (s)))
243# define ROR64_(d, v, s) ((d).i = ROR64((v).i, (s)))
244#else
245# define ROL64_(d, v, s) do { \
246 unsigned _s = (s) & 63u; \
247 uint32 _l = (v).lo, _h = (v).hi; \
248 kludge64 *_d = &(d); \
249 if (_s >= 32) { \
250 _d->hi = LSL32(_l, _s - 32u) | LSR32(_h, 64u - _s); \
251 _d->lo = LSL32(_h, _s - 32u) | LSR32(_l, 64u - _s); \
252 } else if (!_s) { \
253 _d->lo = _l; \
254 _d->hi = _h; \
255 } else { \
256 _d->hi = LSL32(_h, _s) | LSR32(_l, 32u - _s); \
257 _d->lo = LSL32(_l, _s) | LSR32(_h, 32u - _s); \
258 } \
259 } while (0)
260# define ROR64_(d, v, s) do { \
261 unsigned _s = (s) & 63u; \
262 uint32 _l = (v).lo, _h = (v).hi; \
263 kludge64 *_d = &(d); \
264 if (_s >= 32) { \
265 _d->hi = LSR32(_l, _s - 32u) | LSL32(_h, 64u - _s); \
266 _d->lo = LSR32(_h, _s - 32u) | LSL32(_l, 64u - _s); \
267 } else if (!_s) { \
268 _d->lo = _l; \
269 _d->hi = _h; \
270 } else { \
271 _d->hi = LSR32(_h, _s) | LSL32(_l, 32u - _s); \
272 _d->lo = LSR32(_l, _s) | LSL32(_h, 32u - _s); \
273 } \
274 } while (0)
275#endif
276
6b033bc4 277/* --- Storage and retrieval --- */
278
279#define GETBYTE(p, o) (((octet *)(p))[o] & MASK8)
280#define PUTBYTE(p, o, v) (((octet *)(p))[o] = U8((v)))
281
282#define LOAD8(p) (GETBYTE((p), 0))
283#define STORE8(p, v) (PUTBYTE((p), 0, (v)))
284
0d4e268a 285#define LOAD16_B(p) \
286 (((uint16)GETBYTE((p), 0) << 8) | \
287 ((uint16)GETBYTE((p), 1) << 0))
288#define LOAD16_L(p) \
289 (((uint16)GETBYTE((p), 0) << 0) | \
290 ((uint16)GETBYTE((p), 1) << 8))
6b033bc4 291#define LOAD16(p) LOAD16_B((p))
292
0d4e268a 293#define STORE16_B(p, v) \
294 (PUTBYTE((p), 0, (uint16)(v) >> 8), \
295 PUTBYTE((p), 1, (uint16)(v) >> 0))
296#define STORE16_L(p, v) \
297 (PUTBYTE((p), 0, (uint16)(v) >> 0), \
298 PUTBYTE((p), 1, (uint16)(v) >> 8))
6b033bc4 299#define STORE16(p, v) STORE16_B((p), (v))
300
6a0129ea 301#define LOAD24_B(p) \
302 (((uint24)GETBYTE((p), 0) << 16) | \
303 ((uint24)GETBYTE((p), 1) << 8) | \
304 ((uint24)GETBYTE((p), 2) << 0))
305#define LOAD24_L(p) \
306 (((uint24)GETBYTE((p), 0) << 0) | \
307 ((uint24)GETBYTE((p), 1) << 8) | \
308 ((uint24)GETBYTE((p), 2) << 16))
309#define LOAD24(p) LOAD24_B((p))
310
311#define STORE24_B(p, v) \
312 (PUTBYTE((p), 0, (uint24)(v) >> 16), \
313 PUTBYTE((p), 1, (uint24)(v) >> 8), \
314 PUTBYTE((p), 2, (uint24)(v) >> 0))
315#define STORE24_L(p, v) \
316 (PUTBYTE((p), 0, (uint24)(v) >> 0), \
317 PUTBYTE((p), 1, (uint24)(v) >> 8), \
318 PUTBYTE((p), 2, (uint24)(v) >> 16))
319#define STORE24(p, v) STORE24_B((p), (v))
320
6b033bc4 321#define LOAD32_B(p) \
0d4e268a 322 (((uint32)GETBYTE((p), 0) << 24) | \
323 ((uint32)GETBYTE((p), 1) << 16) | \
324 ((uint32)GETBYTE((p), 2) << 8) | \
325 ((uint32)GETBYTE((p), 3) << 0))
6b033bc4 326#define LOAD32_L(p) \
0d4e268a 327 (((uint32)GETBYTE((p), 0) << 0) | \
328 ((uint32)GETBYTE((p), 1) << 8) | \
329 ((uint32)GETBYTE((p), 2) << 16) | \
330 ((uint32)GETBYTE((p), 3) << 24))
6b033bc4 331#define LOAD32(p) LOAD32_B((p))
332
333#define STORE32_B(p, v) \
0d4e268a 334 (PUTBYTE((p), 0, (uint32)(v) >> 24), \
335 PUTBYTE((p), 1, (uint32)(v) >> 16), \
336 PUTBYTE((p), 2, (uint32)(v) >> 8), \
337 PUTBYTE((p), 3, (uint32)(v) >> 0))
6b033bc4 338#define STORE32_L(p, v) \
0d4e268a 339 (PUTBYTE((p), 0, (uint32)(v) >> 0), \
340 PUTBYTE((p), 1, (uint32)(v) >> 8), \
341 PUTBYTE((p), 2, (uint32)(v) >> 16), \
342 PUTBYTE((p), 3, (uint32)(v) >> 24))
6b033bc4 343#define STORE32(p, v) STORE32_B((p), (v))
344
a6f4a484 345#ifdef HAVE_UINT64
346
347# define LOAD64_B(p) \
348 (((uint64)GETBYTE((p), 0) << 56) | \
349 ((uint64)GETBYTE((p), 1) << 48) | \
350 ((uint64)GETBYTE((p), 2) << 40) | \
351 ((uint64)GETBYTE((p), 3) << 32) | \
352 ((uint64)GETBYTE((p), 4) << 24) | \
353 ((uint64)GETBYTE((p), 5) << 16) | \
354 ((uint64)GETBYTE((p), 6) << 8) | \
355 ((uint64)GETBYTE((p), 7) << 0))
356# define LOAD64_L(p) \
357 (((uint64)GETBYTE((p), 0) << 0) | \
358 ((uint64)GETBYTE((p), 1) << 8) | \
359 ((uint64)GETBYTE((p), 2) << 16) | \
360 ((uint64)GETBYTE((p), 3) << 24) | \
361 ((uint64)GETBYTE((p), 4) << 32) | \
362 ((uint64)GETBYTE((p), 5) << 40) | \
363 ((uint64)GETBYTE((p), 6) << 48) | \
364 ((uint64)GETBYTE((p), 7) << 56))
365# define LOAD64(p) LOAD64_B((p))
366# define LOAD64_B_(d, p) ((d).i = LOAD64_B((p)))
367# define LOAD64_L_(d, p) ((d).i = LOAD64_L((p)))
368# define LOAD64_(d, p) LOAD64_B_((d), (p))
369
370# define STORE64_B(p, v) \
371 (PUTBYTE((p), 0, (uint64)(v) >> 56), \
372 PUTBYTE((p), 1, (uint64)(v) >> 48), \
373 PUTBYTE((p), 2, (uint64)(v) >> 40), \
374 PUTBYTE((p), 3, (uint64)(v) >> 32), \
375 PUTBYTE((p), 4, (uint64)(v) >> 24), \
376 PUTBYTE((p), 5, (uint64)(v) >> 16), \
377 PUTBYTE((p), 6, (uint64)(v) >> 8), \
378 PUTBYTE((p), 7, (uint64)(v) >> 0))
379# define STORE64_L(p, v) \
380 (PUTBYTE((p), 0, (uint64)(v) >> 0), \
381 PUTBYTE((p), 1, (uint64)(v) >> 8), \
382 PUTBYTE((p), 2, (uint64)(v) >> 16), \
383 PUTBYTE((p), 3, (uint64)(v) >> 24), \
384 PUTBYTE((p), 4, (uint64)(v) >> 32), \
385 PUTBYTE((p), 5, (uint64)(v) >> 40), \
386 PUTBYTE((p), 6, (uint64)(v) >> 48), \
387 PUTBYTE((p), 7, (uint64)(v) >> 56))
388# define STORE64(p, v) STORE64_B((p), (v))
389# define STORE64_B_(p, v) STORE64_B((p), (v).i)
390# define STORE64_L_(p, v) STORE64_L((p), (v).i)
391# define STORE64_(p, v) STORE64_B_((p), (v))
392
393#else
394
395# define LOAD64_B_(d, p) \
396 ((d).hi = LOAD32_B((octet *)(p) + 0), \
397 (d).lo = LOAD32_B((octet *)(p) + 4))
398# define LOAD64_L_(d, p) \
399 ((d).lo = LOAD32_L((octet *)(p) + 0), \
400 (d).hi = LOAD32_L((octet *)(p) + 4))
401# define LOAD64_(d, p) LOAD64_B_((d), (p))
402
403# define STORE64_B_(p, v) \
404 (STORE32_B((octet *)(p) + 0, (v).hi), \
405 STORE32_B((octet *)(p) + 4, (v).lo))
406# define STORE64_L_(p, v) \
407 (STORE32_L((octet *)(p) + 0, (v).lo), \
408 STORE32_L((octet *)(p) + 4, (v).hi))
409# define STORE64_(p, v) STORE64_B_((p), (v))
410
411#endif
412
413/* --- Other operations on 64-bit integers --- */
414
415#ifdef HAVE_UINT64
416# define SET64(d, h, l) ((d).i = (U64((h)) << 32) | U64((l)))
417# define ASSIGN64(d, x) ((d).i = U64((x)))
418# define HI64(x) U32((x).i >> 32)
419# define LO64(x) U32((x).i)
3b7cea93 420# define GET64(t, x) ((t)(x).i)
a6f4a484 421#else
422# define SET64(d, h, l) ((d).hi = U32(h), (d).lo = U32(l))
423# define ASSIGN64(d, x) \
424 ((d).hi = ((x & ~MASK32) >> 16) >> 16, (d).lo = U32(x))
425# define HI64(x) U32((x).hi)
426# define LO64(x) U32((x).lo)
3b7cea93 427# define GET64(t, x) (((((t)HI64(x) << 16) << 16) & ~MASK32) | (t)LO64(x))
a6f4a484 428#endif
429
430#ifdef HAVE_UINT64
431# define AND64(d, x, y) ((d).i = (x).i & (y).i)
432# define OR64(d, x, y) ((d).i = (x).i | (y).i)
433# define XOR64(d, x, y) ((d).i = (x).i ^ (y).i)
434# define CPL64(d, x) ((d).i = ~(x).i)
435# define ADD64(d, x, y) ((d).i = (x).i + (y).i)
436# define SUB64(d, x, y) ((d).i = (x).i - (y).i)
437# define CMP64(x, op, y) ((x).i op (y).i)
438# define ZERO64(x) ((x) == 0)
439#else
440# define AND64(d, x, y) ((d).lo = (x).lo & (y).lo, (d).hi = (x).hi & (y).hi)
441# define OR64(d, x, y) ((d).lo = (x).lo | (y).lo, (d).hi = (x).hi | (y).hi)
442# define XOR64(d, x, y) ((d).lo = (x).lo ^ (y).lo, (d).hi = (x).hi ^ (y).hi)
443# define CPL64(d, x) ((d).lo = ~(x).lo, (d).hi = ~(x).hi)
444# define ADD64(d, x, y) do { \
445 uint32 _x = U32((x).lo + (y).lo); \
446 (d).hi = (x).hi + (y).hi + (_x < (x).lo); \
447 (d).lo = _x; \
448 } while (0)
449# define SUB64(d, x, y) do { \
450 uint32 _x = U32((x).lo - (y).lo); \
451 (d).hi = (x).hi - (y).hi - (_x > (x).lo); \
452 (d).lo = _x; \
453 } while (0)
454# define CMP64(x, op, y) \
455 ((x).hi == (y).hi ? (x).lo op (y).lo : (x).hi op (y).hi)
456# define ZERO64(x) ((x).lo == 0 && (x).hi == 0)
457#endif
458
6b033bc4 459/*----- That's all, folks -------------------------------------------------*/
460
461#ifdef __cplusplus
462 }
463#endif
464
465#endif