+/*
+ * Mesa 3-D graphics library
+ *
+ * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+
+/**
+ * \file imports.h
+ * Standard C library function wrappers.
+ *
+ * This file provides wrappers for all the standard C library functions
+ * like malloc(), free(), printf(), getenv(), etc.
+ */
+
+
+#ifndef IMPORTS_H
+#define IMPORTS_H
+
+
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include "util/compiler.h"
+#include "util/bitscan.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/**********************************************************************/
+/** Memory macros */
+/*@{*/
+
+/** Allocate a structure of type \p T */
+#define MALLOC_STRUCT(T) (struct T *) malloc(sizeof(struct T))
+/** Allocate and zero a structure of type \p T */
+#define CALLOC_STRUCT(T) (struct T *) calloc(1, sizeof(struct T))
+
+/*@}*/
+
+
+/*
+ * For GL_ARB_vertex_buffer_object we need to treat vertex array pointers
+ * as offsets into buffer stores. Since the vertex array pointer and
+ * buffer store pointer are both pointers and we need to add them, we use
+ * this macro.
+ * Both pointers/offsets are expressed in bytes.
+ */
+#define ADD_POINTERS(A, B) ( (uint8_t *) (A) + (uintptr_t) (B) )
+
+
+/**
+ * Sometimes we treat floats as ints. On x86 systems, moving a float
+ * as an int (thereby using integer registers instead of FP registers) is
+ * a performance win. Typically, this can be done with ordinary casts.
+ * But with gcc's -fstrict-aliasing flag (which defaults to on in gcc 3.0)
+ * these casts generate warnings.
+ * The following union typedef is used to solve that.
+ */
+typedef union { float f; int i; unsigned u; } fi_type;
+
+
+
+/*@}*/
+
+
+/***
+ *** LOG2: Log base 2 of float
+ ***/
+static inline float LOG2(float x)
+{
+#if 0
+ /* This is pretty fast, but not accurate enough (only 2 fractional bits).
+ * Based on code from http://www.stereopsis.com/log2.html
+ */
+ const float y = x * x * x * x;
+ const unsigned ix = *((unsigned *) &y);
+ const unsigned exp = (ix >> 23) & 0xFF;
+ const int log2 = ((int) exp) - 127;
+ return (float) log2 * (1.0 / 4.0); /* 4, because of x^4 above */
+#endif
+ /* Pretty fast, and accurate.
+ * Based on code from http://www.flipcode.com/totd/
+ */
+ fi_type num;
+ int log_2;
+ num.f = x;
+ log_2 = ((num.i >> 23) & 255) - 128;
+ num.i &= ~(255 << 23);
+ num.i += 127 << 23;
+ num.f = ((-1.0f/3) * num.f + 2) * num.f - 2.0f/3;
+ return num.f + log_2;
+}
+
+
+
+/**
+ * finite macro.
+ */
+#if defined(_MSC_VER)
+# define finite _finite
+#endif
+
+
+/***
+ *** IS_INF_OR_NAN: test if float is infinite or NaN
+ ***/
+#if defined(isfinite)
+#define IS_INF_OR_NAN(x) (!isfinite(x))
+#elif defined(finite)
+#define IS_INF_OR_NAN(x) (!finite(x))
+#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
+#define IS_INF_OR_NAN(x) (!isfinite(x))
+#else
+#define IS_INF_OR_NAN(x) (!finite(x))
+#endif
+
+
+/**
+ * Convert float to int by rounding to nearest integer, away from zero.
+ */
+static inline int IROUND(float f)
+{
+ return (int) ((f >= 0.0F) ? (f + 0.5F) : (f - 0.5F));
+}
+
+/**
+ * Convert double to int by rounding to nearest integer, away from zero.
+ */
+static inline int IROUNDD(double d)
+{
+ return (int) ((d >= 0.0) ? (d + 0.5) : (d - 0.5));
+}
+
+/**
+ * Convert float to int64 by rounding to nearest integer.
+ */
+static inline int64_t IROUND64(float f)
+{
+ return (int64_t) ((f >= 0.0F) ? (f + 0.5F) : (f - 0.5F));
+}
+
+
+/**
+ * Convert positive float to int by rounding to nearest integer.
+ */
+static inline int IROUND_POS(float f)
+{
+ assert(f >= 0.0F);
+ return (int) (f + 0.5F);
+}
+
+/** Return (as an integer) floor of float */
+static inline int IFLOOR(float f)
+{
+#if defined(USE_X86_ASM) && defined(__GNUC__) && defined(__i386__)
+ /*
+ * IEEE floor for computers that round to nearest or even.
+ * 'f' must be between -4194304 and 4194303.
+ * This floor operation is done by "(iround(f + .5) + iround(f - .5)) >> 1",
+ * but uses some IEEE specific tricks for better speed.
+ * Contributed by Josh Vanderhoof
+ */
+ int ai, bi;
+ double af, bf;
+ af = (3 << 22) + 0.5 + (double)f;
+ bf = (3 << 22) + 0.5 - (double)f;
+ /* GCC generates an extra fstp/fld without this. */
+ __asm__ ("fstps %0" : "=m" (ai) : "t" (af) : "st");
+ __asm__ ("fstps %0" : "=m" (bi) : "t" (bf) : "st");
+ return (ai - bi) >> 1;
+#else
+ int ai, bi;
+ double af, bf;
+ fi_type u;
+ af = (3 << 22) + 0.5 + (double)f;
+ bf = (3 << 22) + 0.5 - (double)f;
+ u.f = (float) af; ai = u.i;
+ u.f = (float) bf; bi = u.i;
+ return (ai - bi) >> 1;
+#endif
+}
+
+
+/**
+ * Is x a power of two?
+ */
+static inline int
+_mesa_is_pow_two(int x)
+{
+ return !(x & (x - 1));
+}
+
+/**
+ * Round given integer to next higer power of two
+ * If X is zero result is undefined.
+ *
+ * Source for the fallback implementation is
+ * Sean Eron Anderson's webpage "Bit Twiddling Hacks"
+ * http://graphics.stanford.edu/~seander/bithacks.html
+ *
+ * When using builtin function have to do some work
+ * for case when passed values 1 to prevent hiting
+ * undefined result from __builtin_clz. Undefined
+ * results would be different depending on optimization
+ * level used for build.
+ */
+static inline int32_t
+_mesa_next_pow_two_32(uint32_t x)
+{
+#ifdef HAVE___BUILTIN_CLZ
+ uint32_t y = (x != 1);
+ return (1 + y) << ((__builtin_clz(x - y) ^ 31) );
+#else
+ x--;
+ x |= x >> 1;
+ x |= x >> 2;
+ x |= x >> 4;
+ x |= x >> 8;
+ x |= x >> 16;
+ x++;
+ return x;
+#endif
+}
+
+static inline int64_t
+_mesa_next_pow_two_64(uint64_t x)
+{
+#ifdef HAVE___BUILTIN_CLZLL
+ uint64_t y = (x != 1);
+ STATIC_ASSERT(sizeof(x) == sizeof(long long));
+ return (1 + y) << ((__builtin_clzll(x - y) ^ 63));
+#else
+ x--;
+ x |= x >> 1;
+ x |= x >> 2;
+ x |= x >> 4;
+ x |= x >> 8;
+ x |= x >> 16;
+ x |= x >> 32;
+ x++;
+ return x;
+#endif
+}
+
+
+/*
+ * Returns the floor form of binary logarithm for a 32-bit integer.
+ */
+static inline unsigned
+_mesa_logbase2(unsigned n)
+{
+#ifdef HAVE___BUILTIN_CLZ
+ return (31 - __builtin_clz(n | 1));
+#else
+ unsigned pos = 0;
+ if (n >= 1<<16) { n >>= 16; pos += 16; }
+ if (n >= 1<< 8) { n >>= 8; pos += 8; }
+ if (n >= 1<< 4) { n >>= 4; pos += 4; }
+ if (n >= 1<< 2) { n >>= 2; pos += 2; }
+ if (n >= 1<< 1) { pos += 1; }
+ return pos;
+#endif
+}
+
+
+/**********************************************************************
+ * Functions
+ */
+
+extern void *
+_mesa_align_malloc( size_t bytes, unsigned long alignment );
+
+extern void *
+_mesa_align_calloc( size_t bytes, unsigned long alignment );
+
+extern void
+_mesa_align_free( void *ptr );
+
+extern void *
+_mesa_align_realloc(void *oldBuffer, size_t oldSize, size_t newSize,
+ unsigned long alignment);
+
+extern int
+_mesa_snprintf( char *str, size_t size, const char *fmt, ... ) PRINTFLIKE(3, 4);
+
+extern int
+_mesa_vsnprintf(char *str, size_t size, const char *fmt, va_list arg);
+
+
+#if defined(_WIN32) && !defined(HAVE_STRTOK_R)
+#define strtok_r strtok_s
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+
+#endif /* IMPORTS_H */