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Revision: 1.12
Committed: Mon May 28 17:00:19 2012 UTC (11 years, 11 months ago) by root
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Branch: MAIN
Changes since 1.11: +23 -0 lines
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# User Rev Content
1 root 1.1 /*
2     * libecb - http://software.schmorp.de/pkg/libecb
3     *
4 root 1.11 * Copyright (©) 2009-2012 Marc Alexander Lehmann <libecb@schmorp.de>
5 root 1.1 * Copyright (©) 2011 Emanuele Giaquinta
6     * All rights reserved.
7     *
8     * Redistribution and use in source and binary forms, with or without modifica-
9     * tion, are permitted provided that the following conditions are met:
10     *
11     * 1. Redistributions of source code must retain the above copyright notice,
12     * this list of conditions and the following disclaimer.
13     *
14     * 2. Redistributions in binary form must reproduce the above copyright
15     * notice, this list of conditions and the following disclaimer in the
16     * documentation and/or other materials provided with the distribution.
17     *
18     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
19     * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
20     * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
21     * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
22     * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
23     * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
24     * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
25     * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
26     * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
27     * OF THE POSSIBILITY OF SUCH DAMAGE.
28     */
29    
30     #ifndef ECB_H
31     #define ECB_H
32    
33 root 1.12 /* 16 bits major, 16 bits minor */
34     #define ECB_VERSION 0x00010001
35    
36 root 1.2 #ifdef _WIN32
37     typedef signed char int8_t;
38     typedef unsigned char uint8_t;
39     typedef signed short int16_t;
40     typedef unsigned short uint16_t;
41     typedef signed int int32_t;
42     typedef unsigned int uint32_t;
43     #if __GNUC__
44     typedef signed long long int64_t;
45     typedef unsigned long long uint64_t;
46 root 1.3 #else /* _MSC_VER || __BORLANDC__ */
47 root 1.2 typedef signed __int64 int64_t;
48     typedef unsigned __int64 uint64_t;
49     #endif
50 root 1.12 #ifdef _WIN64
51     #define ECB_PTRSIZE 8
52     typedef uint64_t uintptr_t;
53     typedef int64_t intptr_t;
54     #else
55     #define ECB_PTRSIZE 4
56     typedef uint32_t uintptr_t;
57     typedef int32_t intptr_t;
58     #endif
59     typedef intptr_t ptrdiff_t;
60 root 1.2 #else
61     #include <inttypes.h>
62 root 1.12 #if UINTMAX_MAX > 0xffffffffU
63     #define ECB_PTRSIZE 8
64     #else
65     #define ECB_PTRSIZE 4
66     #endif
67 root 1.2 #endif
68 root 1.1
69     /* many compilers define _GNUC_ to some versions but then only implement
70     * what their idiot authors think are the "more important" extensions,
71 root 1.8 * causing enormous grief in return for some better fake benchmark numbers.
72 root 1.1 * or so.
73     * we try to detect these and simply assume they are not gcc - if they have
74     * an issue with that they should have done it right in the first place.
75     */
76     #ifndef ECB_GCC_VERSION
77 root 1.11 #if !defined __GNUC_MINOR__ || defined __INTEL_COMPILER || defined __SUNPRO_C || defined __SUNPRO_CC || defined __llvm__ || defined __clang__
78 root 1.2 #define ECB_GCC_VERSION(major,minor) 0
79     #else
80     #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor)))
81     #endif
82 root 1.1 #endif
83    
84 root 1.4 /*****************************************************************************/
85    
86 root 1.8 /* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
87     /* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */
88    
89 root 1.11 #if ECB_NO_THREADS
90     # define ECB_NO_SMP 1
91     #endif
92    
93 root 1.8 #if ECB_NO_THREADS || ECB_NO_SMP
94     #define ECB_MEMORY_FENCE do { } while (0)
95     #endif
96    
97 root 1.4 #ifndef ECB_MEMORY_FENCE
98 root 1.11 #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
99     #if __i386 || __i386__
100 root 1.5 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory")
101 root 1.7 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE /* non-lock xchg might be enough */
102     #define ECB_MEMORY_FENCE_RELEASE do { } while (0) /* unlikely to change in future cpus */
103 root 1.11 #elif __amd64 || __amd64__ || __x86_64 || __x86_64__
104 root 1.4 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory")
105     #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory")
106 root 1.7 #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") /* play safe - not needed in any current cpu */
107 root 1.8 #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
108     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
109 root 1.11 #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \
110     || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__
111     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
112     #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \
113     || defined __ARM_ARCH_7M__ || defined __ARM_ARCH_7R__
114 root 1.8 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory")
115 root 1.11 #elif __sparc || __sparc__
116     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad | " : : : "memory")
117     #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory")
118     #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore")
119     #elif defined __s390__ || defined __s390x__
120     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory")
121     #elif defined __mips__
122     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory")
123     #elif defined __alpha__
124     #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory")
125 root 1.4 #endif
126     #endif
127     #endif
128    
129     #ifndef ECB_MEMORY_FENCE
130 root 1.11 #if ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__
131 root 1.4 #define ECB_MEMORY_FENCE __sync_synchronize ()
132 root 1.8 /*#define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) */
133     /*#define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release (&dummy ); }) */
134 root 1.7 #elif _MSC_VER >= 1400 /* VC++ 2005 */
135     #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
136     #define ECB_MEMORY_FENCE _ReadWriteBarrier ()
137     #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */
138     #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier ()
139 root 1.11 #elif defined _WIN32
140 root 1.6 #include <WinNT.h>
141 root 1.7 #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */
142 root 1.11 #elif __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110
143     #include <mbarrier.h>
144     #define ECB_MEMORY_FENCE __machine_rw_barrier ()
145     #define ECB_MEMORY_FENCE_ACQUIRE __machine_r_barrier ()
146     #define ECB_MEMORY_FENCE_RELEASE __machine_w_barrier ()
147     #elif __xlC__
148     #define ECB_MEMORY_FENCE __sync ()
149 root 1.4 #endif
150     #endif
151    
152     #ifndef ECB_MEMORY_FENCE
153 root 1.8 #if !ECB_AVOID_PTHREADS
154     /*
155     * if you get undefined symbol references to pthread_mutex_lock,
156     * or failure to find pthread.h, then you should implement
157     * the ECB_MEMORY_FENCE operations for your cpu/compiler
158     * OR provide pthread.h and link against the posix thread library
159     * of your system.
160     */
161     #include <pthread.h>
162     #define ECB_NEEDS_PTHREADS 1
163     #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
164    
165     static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
166     #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
167     #endif
168     #endif
169 root 1.4
170 root 1.11 #if !defined ECB_MEMORY_FENCE_ACQUIRE && defined ECB_MEMORY_FENCE
171 root 1.4 #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
172 root 1.8 #endif
173    
174 root 1.11 #if !defined ECB_MEMORY_FENCE_RELEASE && defined ECB_MEMORY_FENCE
175 root 1.4 #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
176     #endif
177    
178     /*****************************************************************************/
179    
180 root 1.2 #define ECB_C99 (__STDC_VERSION__ >= 199901L)
181    
182     #if __cplusplus
183     #define ecb_inline static inline
184     #elif ECB_GCC_VERSION(2,5)
185     #define ecb_inline static __inline__
186     #elif ECB_C99
187     #define ecb_inline static inline
188     #else
189     #define ecb_inline static
190     #endif
191    
192     #if ECB_GCC_VERSION(3,3)
193     #define ecb_restrict __restrict__
194     #elif ECB_C99
195     #define ecb_restrict restrict
196 root 1.1 #else
197 root 1.2 #define ecb_restrict
198 root 1.1 #endif
199    
200 root 1.2 typedef int ecb_bool;
201    
202 root 1.1 #define ECB_CONCAT_(a, b) a ## b
203     #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b)
204     #define ECB_STRINGIFY_(a) # a
205     #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a)
206    
207 root 1.2 #define ecb_function_ ecb_inline
208 root 1.1
209     #if ECB_GCC_VERSION(3,1)
210 root 1.2 #define ecb_attribute(attrlist) __attribute__(attrlist)
211     #define ecb_is_constant(expr) __builtin_constant_p (expr)
212     #define ecb_expect(expr,value) __builtin_expect ((expr),(value))
213     #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality)
214     #else
215     #define ecb_attribute(attrlist)
216     #define ecb_is_constant(expr) 0
217     #define ecb_expect(expr,value) (expr)
218     #define ecb_prefetch(addr,rw,locality)
219 root 1.1 #endif
220    
221     /* no emulation for ecb_decltype */
222     #if ECB_GCC_VERSION(4,5)
223 root 1.2 #define ecb_decltype(x) __decltype(x)
224 root 1.1 #elif ECB_GCC_VERSION(3,0)
225 root 1.2 #define ecb_decltype(x) __typeof(x)
226 root 1.1 #endif
227    
228     #define ecb_noinline ecb_attribute ((__noinline__))
229     #define ecb_noreturn ecb_attribute ((__noreturn__))
230     #define ecb_unused ecb_attribute ((__unused__))
231     #define ecb_const ecb_attribute ((__const__))
232     #define ecb_pure ecb_attribute ((__pure__))
233    
234 root 1.2 #if ECB_GCC_VERSION(4,3)
235     #define ecb_artificial ecb_attribute ((__artificial__))
236     #define ecb_hot ecb_attribute ((__hot__))
237     #define ecb_cold ecb_attribute ((__cold__))
238     #else
239     #define ecb_artificial
240     #define ecb_hot
241     #define ecb_cold
242     #endif
243    
244     /* put around conditional expressions if you are very sure that the */
245     /* expression is mostly true or mostly false. note that these return */
246     /* booleans, not the expression. */
247 root 1.1 #define ecb_expect_false(expr) ecb_expect (!!(expr), 0)
248     #define ecb_expect_true(expr) ecb_expect (!!(expr), 1)
249 root 1.2 /* for compatibility to the rest of the world */
250 root 1.1 #define ecb_likely(expr) ecb_expect_true (expr)
251     #define ecb_unlikely(expr) ecb_expect_false (expr)
252    
253     /* count trailing zero bits and count # of one bits */
254     #if ECB_GCC_VERSION(3,4)
255 root 1.2 /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */
256     #define ecb_ld32(x) (__builtin_clz (x) ^ 31)
257     #define ecb_ld64(x) (__builtin_clzll (x) ^ 63)
258     #define ecb_ctz32(x) __builtin_ctz (x)
259     #define ecb_ctz64(x) __builtin_ctzll (x)
260     #define ecb_popcount32(x) __builtin_popcount (x)
261     /* no popcountll */
262 root 1.1 #else
263 root 1.2 ecb_function_ int ecb_ctz32 (uint32_t x) ecb_const;
264     ecb_function_ int
265     ecb_ctz32 (uint32_t x)
266     {
267     int r = 0;
268    
269     x &= ~x + 1; /* this isolates the lowest bit */
270    
271 root 1.3 #if ECB_branchless_on_i386
272     r += !!(x & 0xaaaaaaaa) << 0;
273     r += !!(x & 0xcccccccc) << 1;
274     r += !!(x & 0xf0f0f0f0) << 2;
275     r += !!(x & 0xff00ff00) << 3;
276     r += !!(x & 0xffff0000) << 4;
277     #else
278 root 1.2 if (x & 0xaaaaaaaa) r += 1;
279     if (x & 0xcccccccc) r += 2;
280     if (x & 0xf0f0f0f0) r += 4;
281     if (x & 0xff00ff00) r += 8;
282     if (x & 0xffff0000) r += 16;
283 root 1.3 #endif
284 root 1.2
285     return r;
286     }
287    
288     ecb_function_ int ecb_ctz64 (uint64_t x) ecb_const;
289     ecb_function_ int
290     ecb_ctz64 (uint64_t x)
291     {
292     int shift = x & 0xffffffffU ? 0 : 32;
293 root 1.3 return ecb_ctz32 (x >> shift) + shift;
294 root 1.2 }
295    
296     ecb_function_ int ecb_popcount32 (uint32_t x) ecb_const;
297     ecb_function_ int
298     ecb_popcount32 (uint32_t x)
299     {
300     x -= (x >> 1) & 0x55555555;
301     x = ((x >> 2) & 0x33333333) + (x & 0x33333333);
302     x = ((x >> 4) + x) & 0x0f0f0f0f;
303     x *= 0x01010101;
304    
305     return x >> 24;
306     }
307    
308     ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
309     ecb_function_ int ecb_ld32 (uint32_t x)
310     {
311 root 1.3 int r = 0;
312 root 1.2
313 root 1.3 if (x >> 16) { x >>= 16; r += 16; }
314     if (x >> 8) { x >>= 8; r += 8; }
315     if (x >> 4) { x >>= 4; r += 4; }
316     if (x >> 2) { x >>= 2; r += 2; }
317     if (x >> 1) { r += 1; }
318 root 1.2
319     return r;
320     }
321    
322     ecb_function_ int ecb_ld64 (uint64_t x) ecb_const;
323     ecb_function_ int ecb_ld64 (uint64_t x)
324     {
325 root 1.3 int r = 0;
326 root 1.2
327 root 1.3 if (x >> 32) { x >>= 32; r += 32; }
328 root 1.1
329 root 1.3 return r + ecb_ld32 (x);
330 root 1.2 }
331     #endif
332 root 1.1
333 root 1.12 ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) ecb_const;
334     ecb_function_ ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); }
335     ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) ecb_const;
336     ecb_function_ ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); }
337    
338 root 1.11 ecb_function_ uint8_t ecb_bitrev8 (uint8_t x) ecb_const;
339     ecb_function_ uint8_t ecb_bitrev8 (uint8_t x)
340     {
341     return ( (x * 0x0802U & 0x22110U)
342     | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16;
343     }
344    
345     ecb_function_ uint16_t ecb_bitrev16 (uint16_t x) ecb_const;
346     ecb_function_ uint16_t ecb_bitrev16 (uint16_t x)
347     {
348     x = ((x >> 1) & 0x5555) | ((x & 0x5555) << 1);
349     x = ((x >> 2) & 0x3333) | ((x & 0x3333) << 2);
350     x = ((x >> 4) & 0x0f0f) | ((x & 0x0f0f) << 4);
351     x = ( x >> 8 ) | ( x << 8);
352    
353     return x;
354     }
355    
356     ecb_function_ uint32_t ecb_bitrev32 (uint32_t x) ecb_const;
357     ecb_function_ uint32_t ecb_bitrev32 (uint32_t x)
358     {
359     x = ((x >> 1) & 0x55555555) | ((x & 0x55555555) << 1);
360     x = ((x >> 2) & 0x33333333) | ((x & 0x33333333) << 2);
361     x = ((x >> 4) & 0x0f0f0f0f) | ((x & 0x0f0f0f0f) << 4);
362     x = ((x >> 8) & 0x00ff00ff) | ((x & 0x00ff00ff) << 8);
363     x = ( x >> 16 ) | ( x << 16);
364    
365     return x;
366     }
367    
368 root 1.2 /* popcount64 is only available on 64 bit cpus as gcc builtin */
369     /* so for this version we are lazy */
370     ecb_function_ int ecb_popcount64 (uint64_t x) ecb_const;
371     ecb_function_ int
372     ecb_popcount64 (uint64_t x)
373 root 1.1 {
374 root 1.2 return ecb_popcount32 (x) + ecb_popcount32 (x >> 32);
375 root 1.1 }
376    
377 root 1.3 ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) ecb_const;
378     ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) ecb_const;
379     ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) ecb_const;
380     ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) ecb_const;
381     ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) ecb_const;
382     ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) ecb_const;
383     ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) ecb_const;
384     ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) ecb_const;
385    
386     ecb_inline uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); }
387     ecb_inline uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); }
388     ecb_inline uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); }
389     ecb_inline uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); }
390     ecb_inline uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); }
391     ecb_inline uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); }
392     ecb_inline uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); }
393     ecb_inline uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); }
394    
395 root 1.1 #if ECB_GCC_VERSION(4,3)
396 root 1.2 #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16)
397     #define ecb_bswap32(x) __builtin_bswap32 (x)
398     #define ecb_bswap64(x) __builtin_bswap64 (x)
399 root 1.1 #else
400 root 1.3 ecb_function_ uint16_t ecb_bswap16 (uint16_t x) ecb_const;
401     ecb_function_ uint16_t
402     ecb_bswap16 (uint16_t x)
403 root 1.2 {
404 root 1.3 return ecb_rotl16 (x, 8);
405 root 1.2 }
406    
407     ecb_function_ uint32_t ecb_bswap32 (uint32_t x) ecb_const;
408     ecb_function_ uint32_t
409     ecb_bswap32 (uint32_t x)
410     {
411 root 1.3 return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16);
412 root 1.2 }
413    
414     ecb_function_ uint64_t ecb_bswap64 (uint64_t x) ecb_const;
415     ecb_function_ uint64_t
416     ecb_bswap64 (uint64_t x)
417     {
418 root 1.3 return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32);
419 root 1.2 }
420 root 1.1 #endif
421    
422     #if ECB_GCC_VERSION(4,5)
423 root 1.2 #define ecb_unreachable() __builtin_unreachable ()
424 root 1.1 #else
425 root 1.2 /* this seems to work fine, but gcc always emits a warning for it :/ */
426 root 1.11 ecb_inline void ecb_unreachable (void) ecb_noreturn;
427     ecb_inline void ecb_unreachable (void) { }
428 root 1.1 #endif
429    
430 root 1.2 /* try to tell the compiler that some condition is definitely true */
431     #define ecb_assume(cond) do { if (!(cond)) ecb_unreachable (); } while (0)
432    
433 root 1.11 ecb_inline unsigned char ecb_byteorder_helper (void) ecb_const;
434     ecb_inline unsigned char
435 root 1.1 ecb_byteorder_helper (void)
436     {
437     const uint32_t u = 0x11223344;
438     return *(unsigned char *)&u;
439     }
440    
441 root 1.11 ecb_inline ecb_bool ecb_big_endian (void) ecb_const;
442     ecb_inline ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11; }
443     ecb_inline ecb_bool ecb_little_endian (void) ecb_const;
444     ecb_inline ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44; }
445 root 1.1
446 root 1.2 #if ECB_GCC_VERSION(3,0) || ECB_C99
447     #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0))
448 root 1.1 #else
449 root 1.2 #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n)))
450 root 1.1 #endif
451    
452 root 1.10 #if __cplusplus
453     template<typename T>
454     static inline T ecb_div_rd (T val, T div)
455     {
456     return val < 0 ? - ((-val + div - 1) / div) : (val ) / div;
457     }
458     template<typename T>
459     static inline T ecb_div_ru (T val, T div)
460     {
461     return val < 0 ? - ((-val ) / div) : (val + div - 1) / div;
462     }
463     #else
464     #define ecb_div_rd(val,div) ((val) < 0 ? - ((-(val) + (div) - 1) / (div)) : ((val) ) / (div))
465     #define ecb_div_ru(val,div) ((val) < 0 ? - ((-(val) ) / (div)) : ((val) + (div) - 1) / (div))
466     #endif
467    
468 root 1.1 #if ecb_cplusplus_does_not_suck
469 root 1.2 /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */
470     template<typename T, int N>
471     static inline int ecb_array_length (const T (&arr)[N])
472     {
473     return N;
474     }
475 root 1.1 #else
476 root 1.2 #define ecb_array_length(name) (sizeof (name) / sizeof (name [0]))
477 root 1.1 #endif
478    
479     #endif
480