/**
* \file imports.c
* Standard C library function wrappers.
*
* Imports are services which the device driver or window system or
* operating system provides to the core renderer. The core renderer (Mesa)
* will call these functions in order to do memory allocation, simple I/O,
* etc.
*
* Some drivers will want to override/replace this file with something
* specialized, but that'll be rare.
*
* Eventually, I want to move roll the glheader.h file into this.
*
* \todo Functions still needed:
* - scanf
* - qsort
* - rand and RAND_MAX
*/
/*
* Mesa 3-D graphics library
*
* Copyright (C) 1999-2007 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.
*/
#include <stdio.h>
#include <stdarg.h>
#include "c99_math.h"
#include "util/rounding.h" /* for _mesa_roundeven */
#include "imports.h"
#include "context.h"
#include "mtypes.h"
#include "version.h"
#ifdef _GNU_SOURCE
#include <locale.h>
#ifdef __APPLE__
#include <xlocale.h>
#endif
#endif
#ifdef _WIN32
#define vsnprintf _vsnprintf
#elif defined(__IBMC__) || defined(__IBMCPP__)
extern int vsnprintf(char *str, size_t count, const char *fmt, va_list arg);
#endif
/**********************************************************************/
/** \name Memory */
/*@{*/
/**
* Allocate aligned memory.
*
* \param bytes number of bytes to allocate.
* \param alignment alignment (must be greater than zero).
*
* Allocates extra memory to accommodate rounding up the address for
* alignment and to record the real malloc address.
*
* \sa _mesa_align_free().
*/
void *
_mesa_align_malloc(size_t bytes, unsigned long alignment)
{
#if defined(HAVE_POSIX_MEMALIGN)
void *mem;
int err = posix_memalign(& mem, alignment, bytes);
if (err)
return NULL;
return mem;
#elif defined(_WIN32) && defined(_MSC_VER)
return _aligned_malloc(bytes, alignment);
#else
uintptr_t ptr, buf;
ptr
= (uintptr_t)malloc(bytes
+ alignment
+ sizeof(void *)); if (!ptr)
return NULL;
buf = (ptr + alignment + sizeof(void *)) & ~(uintptr_t)(alignment - 1);
*(uintptr_t *)(buf - sizeof(void *)) = ptr;
#ifdef DEBUG
/* mark the non-aligned area */
while ( ptr < buf - sizeof(void *) ) {
*(unsigned long *)ptr = 0xcdcdcdcd;
ptr += sizeof(unsigned long);
}
#endif
return (void *) buf;
#endif /* defined(HAVE_POSIX_MEMALIGN) */
}
/**
* Same as _mesa_align_malloc(), but using calloc(1, ) instead of
* malloc()
*/
void *
_mesa_align_calloc(size_t bytes, unsigned long alignment)
{
#if defined(HAVE_POSIX_MEMALIGN)
void *mem;
mem = _mesa_align_malloc(bytes, alignment);
if (mem != NULL) {
}
return mem;
#elif defined(_WIN32) && defined(_MSC_VER)
void *mem;
mem = _aligned_malloc(bytes, alignment);
if (mem != NULL) {
}
return mem;
#else
uintptr_t ptr, buf;
ptr
= (uintptr_t)calloc(1, bytes
+ alignment
+ sizeof(void *)); if (!ptr)
return NULL;
buf = (ptr + alignment + sizeof(void *)) & ~(uintptr_t)(alignment - 1);
*(uintptr_t *)(buf - sizeof(void *)) = ptr;
#ifdef DEBUG
/* mark the non-aligned area */
while ( ptr < buf - sizeof(void *) ) {
*(unsigned long *)ptr = 0xcdcdcdcd;
ptr += sizeof(unsigned long);
}
#endif
return (void *)buf;
#endif /* defined(HAVE_POSIX_MEMALIGN) */
}
/**
* Free memory which was allocated with either _mesa_align_malloc()
* or _mesa_align_calloc().
* \param ptr pointer to the memory to be freed.
* The actual address to free is stored in the word immediately before the
* address the client sees.
* Note that it is legal to pass NULL pointer to this function and will be
* handled accordingly.
*/
void
_mesa_align_free(void *ptr)
{
#if defined(HAVE_POSIX_MEMALIGN)
#elif defined(_WIN32) && defined(_MSC_VER)
_aligned_free(ptr);
#else
if (ptr) {
void **cubbyHole = (void **) ((char *) ptr - sizeof(void *));
void *realAddr = *cubbyHole;
}
#endif /* defined(HAVE_POSIX_MEMALIGN) */
}
/**
* Reallocate memory, with alignment.
*/
void *
_mesa_align_realloc(void *oldBuffer, size_t oldSize, size_t newSize,
unsigned long alignment)
{
#if defined(_WIN32) && defined(_MSC_VER)
(void) oldSize;
return _aligned_realloc(oldBuffer, newSize, alignment);
#else
const size_t copySize = (oldSize < newSize) ? oldSize : newSize;
void *newBuf = _mesa_align_malloc(newSize, alignment);
if (newBuf && oldBuffer && copySize > 0) {
memcpy(newBuf
, oldBuffer
, copySize
); }
_mesa_align_free(oldBuffer);
return newBuf;
#endif
}
/*@}*/
/**********************************************************************/
/** \name Math */
/*@{*/
#ifndef HAVE___BUILTIN_FFS
/**
* Find the first bit set in a word.
*/
int
ffs(int i)
{
register int bit = 0;
if (i != 0) {
if ((i & 0xffff) == 0) {
bit += 16;
i >>= 16;
}
if ((i & 0xff) == 0) {
bit += 8;
i >>= 8;
}
if ((i & 0xf) == 0) {
bit += 4;
i >>= 4;
}
while ((i & 1) == 0) {
bit++;
i >>= 1;
}
bit++;
}
return bit;
}
#endif
#ifndef HAVE___BUILTIN_FFSLL
/**
* Find position of first bit set in given value.
* XXX Warning: this function can only be used on 64-bit systems!
* \return position of least-significant bit set, starting at 1, return zero
* if no bits set.
*/
int
ffsll(long long int val)
{
int bit;
bit = ffs((int) val);
if (bit != 0)
return bit;
bit = ffs((int) (val >> 32));
if (bit != 0)
return 32 + bit;
return 0;
}
#endif
#ifndef HAVE___BUILTIN_POPCOUNT
/**
* Return number of bits set in given GLuint.
*/
unsigned int
_mesa_bitcount(unsigned int n)
{
unsigned int bits;
for (bits = 0; n > 0; n = n >> 1) {
bits += (n & 1);
}
return bits;
}
#endif
#ifndef HAVE___BUILTIN_POPCOUNTLL
/**
* Return number of bits set in given 64-bit uint.
*/
unsigned int
_mesa_bitcount_64(uint64_t n)
{
unsigned int bits;
for (bits = 0; n > 0; n = n >> 1) {
bits += (n & 1);
}
return bits;
}
#endif
/**
* Convert a 4-byte float to a 2-byte half float.
*
* Not all float32 values can be represented exactly as a float16 value. We
* round such intermediate float32 values to the nearest float16. When the
* float32 lies exactly between to float16 values, we round to the one with
* an even mantissa.
*
* This rounding behavior has several benefits:
* - It has no sign bias.
*
* - It reproduces the behavior of real hardware: opcode F32TO16 in Intel's
* GPU ISA.
*
* - By reproducing the behavior of the GPU (at least on Intel hardware),
* compile-time evaluation of constant packHalf2x16 GLSL expressions will
* result in the same value as if the expression were executed on the GPU.
*/
GLhalfARB
_mesa_float_to_half(float val)
{
const fi_type fi = {val};
const int flt_m = fi.i & 0x7fffff;
const int flt_e = (fi.i >> 23) & 0xff;
const int flt_s = (fi.i >> 31) & 0x1;
int s, e, m = 0;
GLhalfARB result;
/* sign bit */
s = flt_s;
/* handle special cases */
if ((flt_e == 0) && (flt_m == 0)) {
/* zero */
/* m = 0; - already set */
e = 0;
}
else if ((flt_e == 0) && (flt_m != 0)) {
/* denorm -- denorm float maps to 0 half */
/* m = 0; - already set */
e = 0;
}
else if ((flt_e == 0xff) && (flt_m == 0)) {
/* infinity */
/* m = 0; - already set */
e = 31;
}
else if ((flt_e == 0xff) && (flt_m != 0)) {
/* NaN */
m = 1;
e = 31;
}
else {
/* regular number */
const int new_exp = flt_e - 127;
if (new_exp < -14) {
/* The float32 lies in the range (0.0, min_normal16) and is rounded
* to a nearby float16 value. The result will be either zero, subnormal,
* or normal.
*/
e = 0;
m = (int) _mesa_roundevenf((1 << 24) * fabsf(fi.f));
}
else if (new_exp > 15) {
/* map this value to infinity */
/* m = 0; - already set */
e = 31;
}
else {
/* The float32 lies in the range
* [min_normal16, max_normal16 + max_step16)
* and is rounded to a nearby float16 value. The result will be
* either normal or infinite.
*/
e = new_exp + 15;
m = (int) _mesa_roundevenf(flt_m / (float) (1 << 13));
}
}
if (m == 1024) {
/* The float32 was rounded upwards into the range of the next exponent,
* so bump the exponent. This correctly handles the case where f32
* should be rounded up to float16 infinity.
*/
++e;
m = 0;
}
result = (s << 15) | (e << 10) | m;
return result;
}
/**
* Convert a 2-byte half float to a 4-byte float.
* Based on code from:
* http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/008786.html
*/
float
_mesa_half_to_float(GLhalfARB val)
{
/* XXX could also use a 64K-entry lookup table */
const int m = val & 0x3ff;
const int e = (val >> 10) & 0x1f;
const int s = (val >> 15) & 0x1;
int flt_m, flt_e, flt_s;
fi_type fi;
float result;
/* sign bit */
flt_s = s;
/* handle special cases */
if ((e == 0) && (m == 0)) {
/* zero */
flt_m = 0;
flt_e = 0;
}
else if ((e == 0) && (m != 0)) {
/* denorm -- denorm half will fit in non-denorm single */
const float half_denorm = 1.0f / 16384.0f; /* 2^-14 */
float mantissa = ((float) (m)) / 1024.0f;
float sign = s ? -1.0f : 1.0f;
return sign * mantissa * half_denorm;
}
else if ((e == 31) && (m == 0)) {
/* infinity */
flt_e = 0xff;
flt_m = 0;
}
else if ((e == 31) && (m != 0)) {
/* NaN */
flt_e = 0xff;
flt_m = 1;
}
else {
/* regular */
flt_e = e + 112;
flt_m = m << 13;
}
fi.i = (flt_s << 31) | (flt_e << 23) | flt_m;
result = fi.f;
return result;
}
/*@}*/
/**********************************************************************/
/** \name String */
/*@{*/
/** Compute simple checksum/hash for a string */
unsigned int
_mesa_str_checksum(const char *str)
{
/* This could probably be much better */
unsigned int sum, i;
const char *c;
sum = i = 1;
for (c = str; *c; c++, i++)
sum += *c * (i % 100);
return sum + i;
}
/*@}*/
/** Needed due to #ifdef's, above. */
int
_mesa_vsnprintf(char *str, size_t size, const char *fmt, va_list args)
{
return vsnprintf( str, size, fmt, args);
}
/** Wrapper around vsnprintf() */
int
_mesa_snprintf( char *str, size_t size, const char *fmt, ... )
{
int r;
va_list args;
r = vsnprintf( str, size, fmt, args );
return r;
}