3 * Standard C library function wrappers.
5 * Imports are services which the device driver or window system or
6 * operating system provides to the core renderer. The core renderer (Mesa)
7 * will call these functions in order to do memory allocation, simple I/O,
10 * Some drivers will want to override/replace this file with something
11 * specialized, but that'll be rare.
13 * Eventually, I want to move roll the glheader.h file into this.
15 * \todo Functions still needed:
22 * Mesa 3-D graphics library
24 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
26 * Permission is hereby granted, free of charge, to any person obtaining a
27 * copy of this software and associated documentation files (the "Software"),
28 * to deal in the Software without restriction, including without limitation
29 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
30 * and/or sell copies of the Software, and to permit persons to whom the
31 * Software is furnished to do so, subject to the following conditions:
33 * The above copyright notice and this permission notice shall be included
34 * in all copies or substantial portions of the Software.
36 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
37 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
38 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
39 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
40 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
41 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
42 * OTHER DEALINGS IN THE SOFTWARE.
61 #define vsnprintf _vsnprintf
62 #elif defined(__IBMC__) || defined(__IBMCPP__)
63 extern int vsnprintf(char *str
, size_t count
, const char *fmt
, va_list arg
);
66 /**********************************************************************/
71 * Allocate aligned memory.
73 * \param bytes number of bytes to allocate.
74 * \param alignment alignment (must be greater than zero).
76 * Allocates extra memory to accommodate rounding up the address for
77 * alignment and to record the real malloc address.
79 * \sa _mesa_align_free().
82 _mesa_align_malloc(size_t bytes
, unsigned long alignment
)
84 #if defined(HAVE_POSIX_MEMALIGN)
86 int err
= posix_memalign(& mem
, alignment
, bytes
);
90 #elif defined(_WIN32) && defined(_MSC_VER)
91 return _aligned_malloc(bytes
, alignment
);
95 ASSERT( alignment
> 0 );
97 ptr
= (uintptr_t)malloc(bytes
+ alignment
+ sizeof(void *));
101 buf
= (ptr
+ alignment
+ sizeof(void *)) & ~(uintptr_t)(alignment
- 1);
102 *(uintptr_t *)(buf
- sizeof(void *)) = ptr
;
105 /* mark the non-aligned area */
106 while ( ptr
< buf
- sizeof(void *) ) {
107 *(unsigned long *)ptr
= 0xcdcdcdcd;
108 ptr
+= sizeof(unsigned long);
113 #endif /* defined(HAVE_POSIX_MEMALIGN) */
117 * Same as _mesa_align_malloc(), but using calloc(1, ) instead of
121 _mesa_align_calloc(size_t bytes
, unsigned long alignment
)
123 #if defined(HAVE_POSIX_MEMALIGN)
126 mem
= _mesa_align_malloc(bytes
, alignment
);
128 (void) memset(mem
, 0, bytes
);
132 #elif defined(_WIN32) && defined(_MSC_VER)
135 mem
= _aligned_malloc(bytes
, alignment
);
137 (void) memset(mem
, 0, bytes
);
144 ASSERT( alignment
> 0 );
146 ptr
= (uintptr_t)calloc(1, bytes
+ alignment
+ sizeof(void *));
150 buf
= (ptr
+ alignment
+ sizeof(void *)) & ~(uintptr_t)(alignment
- 1);
151 *(uintptr_t *)(buf
- sizeof(void *)) = ptr
;
154 /* mark the non-aligned area */
155 while ( ptr
< buf
- sizeof(void *) ) {
156 *(unsigned long *)ptr
= 0xcdcdcdcd;
157 ptr
+= sizeof(unsigned long);
162 #endif /* defined(HAVE_POSIX_MEMALIGN) */
166 * Free memory which was allocated with either _mesa_align_malloc()
167 * or _mesa_align_calloc().
168 * \param ptr pointer to the memory to be freed.
169 * The actual address to free is stored in the word immediately before the
170 * address the client sees.
171 * Note that it is legal to pass NULL pointer to this function and will be
172 * handled accordingly.
175 _mesa_align_free(void *ptr
)
177 #if defined(HAVE_POSIX_MEMALIGN)
179 #elif defined(_WIN32) && defined(_MSC_VER)
183 void **cubbyHole
= (void **) ((char *) ptr
- sizeof(void *));
184 void *realAddr
= *cubbyHole
;
187 #endif /* defined(HAVE_POSIX_MEMALIGN) */
191 * Reallocate memory, with alignment.
194 _mesa_align_realloc(void *oldBuffer
, size_t oldSize
, size_t newSize
,
195 unsigned long alignment
)
197 #if defined(_WIN32) && defined(_MSC_VER)
199 return _aligned_realloc(oldBuffer
, newSize
, alignment
);
201 const size_t copySize
= (oldSize
< newSize
) ? oldSize
: newSize
;
202 void *newBuf
= _mesa_align_malloc(newSize
, alignment
);
203 if (newBuf
&& oldBuffer
&& copySize
> 0) {
204 memcpy(newBuf
, oldBuffer
, copySize
);
207 _mesa_align_free(oldBuffer
);
214 /** Reallocate memory */
216 _mesa_realloc(void *oldBuffer
, size_t oldSize
, size_t newSize
)
218 const size_t copySize
= (oldSize
< newSize
) ? oldSize
: newSize
;
219 void *newBuffer
= malloc(newSize
);
220 if (newBuffer
&& oldBuffer
&& copySize
> 0)
221 memcpy(newBuffer
, oldBuffer
, copySize
);
229 /**********************************************************************/
236 * Find the first bit set in a word.
241 register int bit
= 0;
243 if ((i
& 0xffff) == 0) {
247 if ((i
& 0xff) == 0) {
251 if ((i
& 0xf) == 0) {
255 while ((i
& 1) == 0) {
266 * Find position of first bit set in given value.
267 * XXX Warning: this function can only be used on 64-bit systems!
268 * \return position of least-significant bit set, starting at 1, return zero
272 ffsll(long long int val
)
276 assert(sizeof(val
) == 8);
278 bit
= ffs((int) val
);
282 bit
= ffs((int) (val
>> 32));
288 #endif /* __GNUC__ */
291 #if !defined(__GNUC__) ||\
292 ((__GNUC__ * 100 + __GNUC_MINOR__) < 304) /* Not gcc 3.4 or later */
294 * Return number of bits set in given GLuint.
297 _mesa_bitcount(unsigned int n
)
300 for (bits
= 0; n
> 0; n
= n
>> 1) {
307 * Return number of bits set in given 64-bit uint.
310 _mesa_bitcount_64(uint64_t n
)
313 for (bits
= 0; n
> 0; n
= n
>> 1) {
321 /* Using C99 rounding functions for roundToEven() implementation is
322 * difficult, because round(), rint, and nearbyint() are affected by
323 * fesetenv(), which the application may have done for its own
324 * purposes. Mesa's IROUND macro is close to what we want, but it
325 * rounds away from 0 on n + 0.5.
328 _mesa_round_to_even(float val
)
330 int rounded
= IROUND(val
);
332 if (val
- floor(val
) == 0.5) {
333 if (rounded
% 2 != 0)
334 rounded
+= val
> 0 ? -1 : 1;
342 * Convert a 4-byte float to a 2-byte half float.
344 * Not all float32 values can be represented exactly as a float16 value. We
345 * round such intermediate float32 values to the nearest float16. When the
346 * float32 lies exactly between to float16 values, we round to the one with
349 * This rounding behavior has several benefits:
350 * - It has no sign bias.
352 * - It reproduces the behavior of real hardware: opcode F32TO16 in Intel's
355 * - By reproducing the behavior of the GPU (at least on Intel hardware),
356 * compile-time evaluation of constant packHalf2x16 GLSL expressions will
357 * result in the same value as if the expression were executed on the GPU.
360 _mesa_float_to_half(float val
)
362 const fi_type fi
= {val
};
363 const int flt_m
= fi
.i
& 0x7fffff;
364 const int flt_e
= (fi
.i
>> 23) & 0xff;
365 const int flt_s
= (fi
.i
>> 31) & 0x1;
372 /* handle special cases */
373 if ((flt_e
== 0) && (flt_m
== 0)) {
375 /* m = 0; - already set */
378 else if ((flt_e
== 0) && (flt_m
!= 0)) {
379 /* denorm -- denorm float maps to 0 half */
380 /* m = 0; - already set */
383 else if ((flt_e
== 0xff) && (flt_m
== 0)) {
385 /* m = 0; - already set */
388 else if ((flt_e
== 0xff) && (flt_m
!= 0)) {
395 const int new_exp
= flt_e
- 127;
397 /* The float32 lies in the range (0.0, min_normal16) and is rounded
398 * to a nearby float16 value. The result will be either zero, subnormal,
402 m
= _mesa_round_to_even((1 << 24) * fabsf(fi
.f
));
404 else if (new_exp
> 15) {
405 /* map this value to infinity */
406 /* m = 0; - already set */
410 /* The float32 lies in the range
411 * [min_normal16, max_normal16 + max_step16)
412 * and is rounded to a nearby float16 value. The result will be
413 * either normal or infinite.
416 m
= _mesa_round_to_even(flt_m
/ (float) (1 << 13));
420 assert(0 <= m
&& m
<= 1024);
422 /* The float32 was rounded upwards into the range of the next exponent,
423 * so bump the exponent. This correctly handles the case where f32
424 * should be rounded up to float16 infinity.
430 result
= (s
<< 15) | (e
<< 10) | m
;
436 * Convert a 2-byte half float to a 4-byte float.
437 * Based on code from:
438 * http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/008786.html
441 _mesa_half_to_float(GLhalfARB val
)
443 /* XXX could also use a 64K-entry lookup table */
444 const int m
= val
& 0x3ff;
445 const int e
= (val
>> 10) & 0x1f;
446 const int s
= (val
>> 15) & 0x1;
447 int flt_m
, flt_e
, flt_s
;
454 /* handle special cases */
455 if ((e
== 0) && (m
== 0)) {
460 else if ((e
== 0) && (m
!= 0)) {
461 /* denorm -- denorm half will fit in non-denorm single */
462 const float half_denorm
= 1.0f
/ 16384.0f
; /* 2^-14 */
463 float mantissa
= ((float) (m
)) / 1024.0f
;
464 float sign
= s
? -1.0f
: 1.0f
;
465 return sign
* mantissa
* half_denorm
;
467 else if ((e
== 31) && (m
== 0)) {
472 else if ((e
== 31) && (m
!= 0)) {
483 fi
.i
= (flt_s
<< 31) | (flt_e
<< 23) | flt_m
;
491 /**********************************************************************/
492 /** \name Sort & Search */
496 * Wrapper for bsearch().
499 _mesa_bsearch( const void *key
, const void *base
, size_t nmemb
, size_t size
,
500 int (*compar
)(const void *, const void *) )
502 #if defined(_WIN32_WCE)
507 mid
= (char *)base
+ nmemb
* size
;
508 cmp
= (*compar
)(key
, mid
);
512 base
= (char *)mid
+ size
;
518 return bsearch(key
, base
, nmemb
, size
, compar
);
525 /**********************************************************************/
526 /** \name Environment vars */
530 * Wrapper for getenv().
533 _mesa_getenv( const char *var
)
535 #if defined(_XBOX) || defined(_WIN32_WCE)
545 /**********************************************************************/
550 * Implemented using malloc() and strcpy.
551 * Note that NULL is handled accordingly.
554 _mesa_strdup( const char *s
)
557 size_t l
= strlen(s
);
558 char *s2
= malloc(l
+ 1);
568 /** Wrapper around strtof() */
570 _mesa_strtof( const char *s
, char **end
)
572 #if defined(_GNU_SOURCE) && !defined(__CYGWIN__) && !defined(__FreeBSD__) && \
573 !defined(ANDROID) && !defined(__HAIKU__) && !defined(__UCLIBC__) && \
575 static locale_t loc
= NULL
;
577 loc
= newlocale(LC_CTYPE_MASK
, "C", NULL
);
579 return strtof_l(s
, end
, loc
);
580 #elif defined(_ISOC99_SOURCE) || (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE >= 600)
581 return strtof(s
, end
);
583 return (float)strtod(s
, end
);
587 /** Compute simple checksum/hash for a string */
589 _mesa_str_checksum(const char *str
)
591 /* This could probably be much better */
595 for (c
= str
; *c
; c
++, i
++)
596 sum
+= *c
* (i
% 100);
604 /** Needed due to #ifdef's, above. */
606 _mesa_vsnprintf(char *str
, size_t size
, const char *fmt
, va_list args
)
608 return vsnprintf( str
, size
, fmt
, args
);
611 /** Wrapper around vsnprintf() */
613 _mesa_snprintf( char *str
, size_t size
, const char *fmt
, ... )
617 va_start( args
, fmt
);
618 r
= vsnprintf( str
, size
, fmt
, args
);