1/*
2 * Mesa 3-D graphics library
3 *
4 * Copyright (C) 1999-2008  Brian Paul   All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25
26/**
27 * \file imports.h
28 * Standard C library function wrappers.
29 *
30 * This file provides wrappers for all the standard C library functions
31 * like malloc(), free(), printf(), getenv(), etc.
32 */
33
34
35#ifndef IMPORTS_H
36#define IMPORTS_H
37
38
39#include <stdlib.h>
40#include <stdarg.h>
41#include <string.h>
42#include "compiler.h"
43#include "glheader.h"
44#include "errors.h"
45#include "util/bitscan.h"
46
47#ifdef __cplusplus
48extern "C" {
49#endif
50
51
52/**********************************************************************/
53/** Memory macros */
54/*@{*/
55
56/** Allocate a structure of type \p T */
57#define MALLOC_STRUCT(T)   (struct T *) malloc(sizeof(struct T))
58/** Allocate and zero a structure of type \p T */
59#define CALLOC_STRUCT(T)   (struct T *) calloc(1, sizeof(struct T))
60
61/*@}*/
62
63
64/*
65 * For GL_ARB_vertex_buffer_object we need to treat vertex array pointers
66 * as offsets into buffer stores.  Since the vertex array pointer and
67 * buffer store pointer are both pointers and we need to add them, we use
68 * this macro.
69 * Both pointers/offsets are expressed in bytes.
70 */
71#define ADD_POINTERS(A, B)  ( (GLubyte *) (A) + (uintptr_t) (B) )
72
73
74/**
75 * Sometimes we treat GLfloats as GLints.  On x86 systems, moving a float
76 * as an int (thereby using integer registers instead of FP registers) is
77 * a performance win.  Typically, this can be done with ordinary casts.
78 * But with gcc's -fstrict-aliasing flag (which defaults to on in gcc 3.0)
79 * these casts generate warnings.
80 * The following union typedef is used to solve that.
81 */
82typedef union { GLfloat f; GLint i; GLuint u; } fi_type;
83
84
85
86#if defined(_MSC_VER)
87#define strcasecmp(s1, s2) _stricmp(s1, s2)
88#endif
89/*@}*/
90
91
92/***
93 *** LOG2: Log base 2 of float
94 ***/
95static inline GLfloat LOG2(GLfloat x)
96{
97#if 0
98   /* This is pretty fast, but not accurate enough (only 2 fractional bits).
99    * Based on code from http://www.stereopsis.com/log2.html
100    */
101   const GLfloat y = x * x * x * x;
102   const GLuint ix = *((GLuint *) &y);
103   const GLuint exp = (ix >> 23) & 0xFF;
104   const GLint log2 = ((GLint) exp) - 127;
105   return (GLfloat) log2 * (1.0 / 4.0);  /* 4, because of x^4 above */
106#endif
107   /* Pretty fast, and accurate.
108    * Based on code from http://www.flipcode.com/totd/
109    */
110   fi_type num;
111   GLint log_2;
112   num.f = x;
113   log_2 = ((num.i >> 23) & 255) - 128;
114   num.i &= ~(255 << 23);
115   num.i += 127 << 23;
116   num.f = ((-1.0f/3) * num.f + 2) * num.f - 2.0f/3;
117   return num.f + log_2;
118}
119
120
121
122/**
123 * finite macro.
124 */
125#if defined(_MSC_VER)
126#  define finite _finite
127#endif
128
129
130/***
131 *** IS_INF_OR_NAN: test if float is infinite or NaN
132 ***/
133#if defined(isfinite)
134#define IS_INF_OR_NAN(x)        (!isfinite(x))
135#elif defined(finite)
136#define IS_INF_OR_NAN(x)        (!finite(x))
137#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
138#define IS_INF_OR_NAN(x)        (!isfinite(x))
139#else
140#define IS_INF_OR_NAN(x)        (!finite(x))
141#endif
142
143
144/**
145 * Convert float to int by rounding to nearest integer, away from zero.
146 */
147static inline int IROUND(float f)
148{
149   return (int) ((f >= 0.0F) ? (f + 0.5F) : (f - 0.5F));
150}
151
152/**
153 * Convert double to int by rounding to nearest integer, away from zero.
154 */
155static inline int IROUNDD(double d)
156{
157   return (int) ((d >= 0.0) ? (d + 0.5) : (d - 0.5));
158}
159
160/**
161 * Convert float to int64 by rounding to nearest integer.
162 */
163static inline GLint64 IROUND64(float f)
164{
165   return (GLint64) ((f >= 0.0F) ? (f + 0.5F) : (f - 0.5F));
166}
167
168
169/**
170 * Convert positive float to int by rounding to nearest integer.
171 */
172static inline int IROUND_POS(float f)
173{
174   assert(f >= 0.0F);
175   return (int) (f + 0.5F);
176}
177
178/** Return (as an integer) floor of float */
179static inline int IFLOOR(float f)
180{
181#if defined(USE_X86_ASM) && defined(__GNUC__) && defined(__i386__)
182   /*
183    * IEEE floor for computers that round to nearest or even.
184    * 'f' must be between -4194304 and 4194303.
185    * This floor operation is done by "(iround(f + .5) + iround(f - .5)) >> 1",
186    * but uses some IEEE specific tricks for better speed.
187    * Contributed by Josh Vanderhoof
188    */
189   int ai, bi;
190   double af, bf;
191   af = (3 << 22) + 0.5 + (double)f;
192   bf = (3 << 22) + 0.5 - (double)f;
193   /* GCC generates an extra fstp/fld without this. */
194   __asm__ ("fstps %0" : "=m" (ai) : "t" (af) : "st");
195   __asm__ ("fstps %0" : "=m" (bi) : "t" (bf) : "st");
196   return (ai - bi) >> 1;
197#else
198   int ai, bi;
199   double af, bf;
200   fi_type u;
201   af = (3 << 22) + 0.5 + (double)f;
202   bf = (3 << 22) + 0.5 - (double)f;
203   u.f = (float) af;  ai = u.i;
204   u.f = (float) bf;  bi = u.i;
205   return (ai - bi) >> 1;
206#endif
207}
208
209
210/**
211 * Is x a power of two?
212 */
213static inline int
214_mesa_is_pow_two(int x)
215{
216   return !(x & (x - 1));
217}
218
219/**
220 * Round given integer to next higer power of two
221 * If X is zero result is undefined.
222 *
223 * Source for the fallback implementation is
224 * Sean Eron Anderson's webpage "Bit Twiddling Hacks"
225 * http://graphics.stanford.edu/~seander/bithacks.html
226 *
227 * When using builtin function have to do some work
228 * for case when passed values 1 to prevent hiting
229 * undefined result from __builtin_clz. Undefined
230 * results would be different depending on optimization
231 * level used for build.
232 */
233static inline int32_t
234_mesa_next_pow_two_32(uint32_t x)
235{
236#ifdef HAVE___BUILTIN_CLZ
237	uint32_t y = (x != 1);
238	return (1 + y) << ((__builtin_clz(x - y) ^ 31) );
239#else
240	x--;
241	x |= x >> 1;
242	x |= x >> 2;
243	x |= x >> 4;
244	x |= x >> 8;
245	x |= x >> 16;
246	x++;
247	return x;
248#endif
249}
250
251static inline int64_t
252_mesa_next_pow_two_64(uint64_t x)
253{
254#ifdef HAVE___BUILTIN_CLZLL
255	uint64_t y = (x != 1);
256	STATIC_ASSERT(sizeof(x) == sizeof(long long));
257	return (1 + y) << ((__builtin_clzll(x - y) ^ 63));
258#else
259	x--;
260	x |= x >> 1;
261	x |= x >> 2;
262	x |= x >> 4;
263	x |= x >> 8;
264	x |= x >> 16;
265	x |= x >> 32;
266	x++;
267	return x;
268#endif
269}
270
271
272/*
273 * Returns the floor form of binary logarithm for a 32-bit integer.
274 */
275static inline GLuint
276_mesa_logbase2(GLuint n)
277{
278#ifdef HAVE___BUILTIN_CLZ
279   return (31 - __builtin_clz(n | 1));
280#else
281   GLuint pos = 0;
282   if (n >= 1<<16) { n >>= 16; pos += 16; }
283   if (n >= 1<< 8) { n >>=  8; pos +=  8; }
284   if (n >= 1<< 4) { n >>=  4; pos +=  4; }
285   if (n >= 1<< 2) { n >>=  2; pos +=  2; }
286   if (n >= 1<< 1) {           pos +=  1; }
287   return pos;
288#endif
289}
290
291
292/**
293 * Return 1 if this is a little endian machine, 0 if big endian.
294 */
295static inline GLboolean
296_mesa_little_endian(void)
297{
298   const GLuint ui = 1; /* intentionally not static */
299   return *((const GLubyte *) &ui);
300}
301
302
303
304/**********************************************************************
305 * Functions
306 */
307
308extern void *
309_mesa_align_malloc( size_t bytes, unsigned long alignment );
310
311extern void *
312_mesa_align_calloc( size_t bytes, unsigned long alignment );
313
314extern void
315_mesa_align_free( void *ptr );
316
317extern void *
318_mesa_align_realloc(void *oldBuffer, size_t oldSize, size_t newSize,
319                    unsigned long alignment);
320
321extern void *
322_mesa_exec_malloc( GLuint size );
323
324extern void
325_mesa_exec_free( void *addr );
326
327
328#ifdef HAVE___BUILTIN_POPCOUNT
329#define _mesa_bitcount(i) __builtin_popcount(i)
330#else
331extern unsigned int
332_mesa_bitcount(unsigned int n);
333#endif
334
335#ifdef HAVE___BUILTIN_POPCOUNTLL
336#define _mesa_bitcount_64(i) __builtin_popcountll(i)
337#else
338extern unsigned int
339_mesa_bitcount_64(uint64_t n);
340#endif
341
342
343static inline bool
344_mesa_half_is_negative(GLhalfARB h)
345{
346   return h & 0x8000;
347}
348
349extern int
350_mesa_snprintf( char *str, size_t size, const char *fmt, ... ) PRINTFLIKE(3, 4);
351
352extern int
353_mesa_vsnprintf(char *str, size_t size, const char *fmt, va_list arg);
354
355
356#if defined(_MSC_VER) && !defined(snprintf)
357#define snprintf _snprintf
358#endif
359
360#if defined(_WIN32) && !defined(strtok_r)
361#define strtok_r strtok_s
362#endif
363
364#ifdef __cplusplus
365}
366#endif
367
368
369#endif /* IMPORTS_H */
370