xserver libX11 pixman mesa git update 22 Feb 2011

1 files changed, 1028 insertions, 1033 deletions

diff --git a/mesalib/src/mesa/main/imports.c b/mesalib/src/mesa/main/imports.c
index f98098230..bf89815f2 100644
--- a/mesalib/src/mesa/main/imports.c
+++ b/mesalib/src/mesa/main/imports.c
@@ -1,1033 +1,1028 @@
-/**

- * \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

- * Version:  7.1

- *

- * 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

- * BRIAN PAUL 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 "imports.h"

-#include "context.h"

-#include "mtypes.h"

-#include "version.h"

-

-#ifdef _GNU_SOURCE

-#include <locale.h>

-#ifdef __APPLE__

-#include <xlocale.h>

-#endif

-#endif

-

-

-#define MAXSTRING 4000  /* for vsnprintf() */

-

-#ifdef WIN32

-#define vsnprintf _vsnprintf

-#elif defined(__IBMC__) || defined(__IBMCPP__) || ( defined(__VMS) && __CRTL_VER < 70312000 )

-extern int vsnprintf(char *str, size_t count, const char *fmt, va_list arg);

-#ifdef __VMS

-#include "vsnprintf.c"

-#endif

-#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;

-

-   ASSERT( alignment > 0 );

-

-   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) {

-      (void) memset(mem, 0, bytes);

-   }

-

-   return mem;

-#elif defined(_WIN32) && defined(_MSC_VER)

-   void *mem;

-

-   mem = _aligned_malloc(bytes, alignment);

-   if (mem != NULL) {

-      (void) memset(mem, 0, bytes);

-   }

-

-   return mem;

-#else

-   uintptr_t ptr, buf;

-

-   ASSERT( alignment > 0 );

-

-   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.

- */

-void

-_mesa_align_free(void *ptr)

-{

-#if defined(HAVE_POSIX_MEMALIGN)

-   free(ptr);

-#elif defined(_WIN32) && defined(_MSC_VER)

-   _aligned_free(ptr);

-#else

-   void **cubbyHole = (void **) ((char *) ptr - sizeof(void *));

-   void *realAddr = *cubbyHole;

-   free(realAddr);

-#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);

-   }

-   if (oldBuffer)

-      _mesa_align_free(oldBuffer);

-   return newBuf;

-#endif

-}

-

-

-

-/** Reallocate memory */

-void *

-_mesa_realloc(void *oldBuffer, size_t oldSize, size_t newSize)

-{

-   const size_t copySize = (oldSize < newSize) ? oldSize : newSize;

-   void *newBuffer = malloc(newSize);

-   if (newBuffer && oldBuffer && copySize > 0)

-      memcpy(newBuffer, oldBuffer, copySize);

-   if (oldBuffer)

-      free(oldBuffer);

-   return newBuffer;

-}

-

-/**

- * Fill memory with a constant 16bit word.

- * \param dst destination pointer.

- * \param val value.

- * \param n number of words.

- */

-void

-_mesa_memset16( unsigned short *dst, unsigned short val, size_t n )

-{

-   while (n-- > 0)

-      *dst++ = val;

-}

-

-/*@}*/

-

-

-/**********************************************************************/

-/** \name Math */

-/*@{*/

-

-/** Wrapper around sqrt() */

-double

-_mesa_sqrtd(double x)

-{

-   return sqrt(x);

-}

-

-

-/*

- * A High Speed, Low Precision Square Root

- * by Paul Lalonde and Robert Dawson

- * from "Graphics Gems", Academic Press, 1990

- *

- * SPARC implementation of a fast square root by table

- * lookup.

- * SPARC floating point format is as follows:

- *

- * BIT 31 	30 	23 	22 	0

- *     sign	exponent	mantissa

- */

-static short sqrttab[0x100];    /* declare table of square roots */

-

-void

-_mesa_init_sqrt_table(void)

-{

-#if defined(USE_IEEE) && !defined(DEBUG)

-   unsigned short i;

-   fi_type fi;     /* to access the bits of a float in  C quickly  */

-                   /* we use a union defined in glheader.h         */

-

-   for(i=0; i<= 0x7f; i++) {

-      fi.i = 0;

-

-      /*

-       * Build a float with the bit pattern i as mantissa

-       * and an exponent of 0, stored as 127

-       */

-

-      fi.i = (i << 16) | (127 << 23);

-      fi.f = _mesa_sqrtd(fi.f);

-

-      /*

-       * Take the square root then strip the first 7 bits of

-       * the mantissa into the table

-       */

-

-      sqrttab[i] = (fi.i & 0x7fffff) >> 16;

-

-      /*

-       * Repeat the process, this time with an exponent of

-       * 1, stored as 128

-       */

-

-      fi.i = 0;

-      fi.i = (i << 16) | (128 << 23);

-      fi.f = sqrt(fi.f);

-      sqrttab[i+0x80] = (fi.i & 0x7fffff) >> 16;

-   }

-#else

-   (void) sqrttab;  /* silence compiler warnings */

-#endif /*HAVE_FAST_MATH*/

-}

-

-

-/**

- * Single precision square root.

- */

-float

-_mesa_sqrtf( float x )

-{

-#if defined(USE_IEEE) && !defined(DEBUG)

-   fi_type num;

-                                /* to access the bits of a float in C

-                                 * we use a union from glheader.h     */

-

-   short e;                     /* the exponent */

-   if (x == 0.0F) return 0.0F;  /* check for square root of 0 */

-   num.f = x;

-   e = (num.i >> 23) - 127;     /* get the exponent - on a SPARC the */

-                                /* exponent is stored with 127 added */

-   num.i &= 0x7fffff;           /* leave only the mantissa */

-   if (e & 0x01) num.i |= 0x800000;

-                                /* the exponent is odd so we have to */

-                                /* look it up in the second half of  */

-                                /* the lookup table, so we set the   */

-                                /* high bit                                */

-   e >>= 1;                     /* divide the exponent by two */

-                                /* note that in C the shift */

-                                /* operators are sign preserving */

-                                /* for signed operands */

-   /* Do the table lookup, based on the quaternary mantissa,

-    * then reconstruct the result back into a float

-    */

-   num.i = ((sqrttab[num.i >> 16]) << 16) | ((e + 127) << 23);

-

-   return num.f;

-#else

-   return (float) _mesa_sqrtd((double) x);

-#endif

-}

-

-

-/**

- inv_sqrt - A single precision 1/sqrt routine for IEEE format floats.

- written by Josh Vanderhoof, based on newsgroup posts by James Van Buskirk

- and Vesa Karvonen.

-*/

-float

-_mesa_inv_sqrtf(float n)

-{

-#if defined(USE_IEEE) && !defined(DEBUG)

-        float r0, x0, y0;

-        float r1, x1, y1;

-        float r2, x2, y2;

-#if 0 /* not used, see below -BP */

-        float r3, x3, y3;

-#endif

-        fi_type u;

-        unsigned int magic;

-

-        /*

-         Exponent part of the magic number -

-

-         We want to:

-         1. subtract the bias from the exponent,

-         2. negate it

-         3. divide by two (rounding towards -inf)

-         4. add the bias back

-

-         Which is the same as subtracting the exponent from 381 and dividing

-         by 2.

-

-         floor(-(x - 127) / 2) + 127 = floor((381 - x) / 2)

-        */

-

-        magic = 381 << 23;

-

-        /*

-         Significand part of magic number -

-

-         With the current magic number, "(magic - u.i) >> 1" will give you:

-

-         for 1 <= u.f <= 2: 1.25 - u.f / 4

-         for 2 <= u.f <= 4: 1.00 - u.f / 8

-

-         This isn't a bad approximation of 1/sqrt.  The maximum difference from

-         1/sqrt will be around .06.  After three Newton-Raphson iterations, the

-         maximum difference is less than 4.5e-8.  (Which is actually close

-         enough to make the following bias academic...)

-

-         To get a better approximation you can add a bias to the magic

-         number.  For example, if you subtract 1/2 of the maximum difference in

-         the first approximation (.03), you will get the following function:

-

-         for 1 <= u.f <= 2:    1.22 - u.f / 4

-         for 2 <= u.f <= 3.76: 0.97 - u.f / 8

-         for 3.76 <= u.f <= 4: 0.72 - u.f / 16

-         (The 3.76 to 4 range is where the result is < .5.)

-

-         This is the closest possible initial approximation, but with a maximum

-         error of 8e-11 after three NR iterations, it is still not perfect.  If

-         you subtract 0.0332281 instead of .03, the maximum error will be

-         2.5e-11 after three NR iterations, which should be about as close as

-         is possible.

-

-         for 1 <= u.f <= 2:    1.2167719 - u.f / 4

-         for 2 <= u.f <= 3.73: 0.9667719 - u.f / 8

-         for 3.73 <= u.f <= 4: 0.7167719 - u.f / 16

-

-        */

-

-        magic -= (int)(0.0332281 * (1 << 25));

-

-        u.f = n;

-        u.i = (magic - u.i) >> 1;

-

-        /*

-         Instead of Newton-Raphson, we use Goldschmidt's algorithm, which

-         allows more parallelism.  From what I understand, the parallelism

-         comes at the cost of less precision, because it lets error

-         accumulate across iterations.

-        */

-        x0 = 1.0f;

-        y0 = 0.5f * n;

-        r0 = u.f;

-

-        x1 = x0 * r0;

-        y1 = y0 * r0 * r0;

-        r1 = 1.5f - y1;

-

-        x2 = x1 * r1;

-        y2 = y1 * r1 * r1;

-        r2 = 1.5f - y2;

-

-#if 1

-        return x2 * r2;  /* we can stop here, and be conformant -BP */

-#else

-        x3 = x2 * r2;

-        y3 = y2 * r2 * r2;

-        r3 = 1.5f - y3;

-

-        return x3 * r3;

-#endif

-#else

-        return (float) (1.0 / sqrt(n));

-#endif

-}

-

-/**

- * Find the first bit set in a word.

- */

-int

-_mesa_ffs(int32_t i)

-{

-#if (defined(_WIN32) ) || defined(__IBMC__) || defined(__IBMCPP__)

-   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;

-#else

-   return ffs(i);

-#endif

-}

-

-

-/**

- * 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

-_mesa_ffsll(int64_t val)

-{

-#ifdef ffsll

-   return ffsll(val);

-#else

-   int bit;

-

-   assert(sizeof(val) == 8);

-

-   bit = _mesa_ffs((int32_t)val);

-   if (bit != 0)

-      return bit;

-

-   bit = _mesa_ffs((int32_t)(val >> 32));

-   if (bit != 0)

-      return 32 + bit;

-

-   return 0;

-#endif

-}

-

-

-/**

- * Return number of bits set in given GLuint.

- */

-unsigned int

-_mesa_bitcount(unsigned int n)

-{

-#if defined(__GNUC__) && \

-	((_GNUC__ == 3 && __GNUC_MINOR__ >= 4) || __GNUC__ >= 4)

-   return __builtin_popcount(n);

-#else

-   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.

- * Based on code from:

- * http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/008786.html

- */

-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 < -24) {

-         /* this maps to 0 */

-         /* m = 0; - already set */

-         e = 0;

-      }

-      else if (new_exp < -14) {

-         /* this maps to a denorm */

-         unsigned int exp_val = (unsigned int) (-14 - new_exp); /* 2^-exp_val*/

-         e = 0;

-         switch (exp_val) {

-            case 0:

-               _mesa_warning(NULL,

-                   "float_to_half: logical error in denorm creation!\n");

-               /* m = 0; - already set */

-               break;

-            case 1: m = 512 + (flt_m >> 14); break;

-            case 2: m = 256 + (flt_m >> 15); break;

-            case 3: m = 128 + (flt_m >> 16); break;

-            case 4: m = 64 + (flt_m >> 17); break;

-            case 5: m = 32 + (flt_m >> 18); break;

-            case 6: m = 16 + (flt_m >> 19); break;

-            case 7: m = 8 + (flt_m >> 20); break;

-            case 8: m = 4 + (flt_m >> 21); break;

-            case 9: m = 2 + (flt_m >> 22); break;

-            case 10: m = 1; break;

-         }

-      }

-      else if (new_exp > 15) {

-         /* map this value to infinity */

-         /* m = 0; - already set */

-         e = 31;

-      }

-      else {

-         /* regular */

-         e = new_exp + 15;

-         m = flt_m >> 13;

-      }

-   }

-

-   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 Sort & Search */

-/*@{*/

-

-/**

- * Wrapper for bsearch().

- */

-void *

-_mesa_bsearch( const void *key, const void *base, size_t nmemb, size_t size, 

-               int (*compar)(const void *, const void *) )

-{

-#if defined(_WIN32_WCE)

-   void *mid;

-   int cmp;

-   while (nmemb) {

-      nmemb >>= 1;

-      mid = (char *)base + nmemb * size;

-      cmp = (*compar)(key, mid);

-      if (cmp == 0)

-	 return mid;

-      if (cmp > 0) {

-	 base = (char *)mid + size;

-	 --nmemb;

-      }

-   }

-   return NULL;

-#else

-   return bsearch(key, base, nmemb, size, compar);

-#endif

-}

-

-/*@}*/

-

-

-/**********************************************************************/

-/** \name Environment vars */

-/*@{*/

-

-/**

- * Wrapper for getenv().

- */

-char *

-_mesa_getenv( const char *var )

-{

-#if defined(_XBOX) || defined(_WIN32_WCE)

-   return NULL;

-#else

-   return getenv(var);

-#endif

-}

-

-/*@}*/

-

-

-/**********************************************************************/

-/** \name String */

-/*@{*/

-

-/**

- * Implemented using malloc() and strcpy.

- * Note that NULL is handled accordingly.

- */

-char *

-_mesa_strdup( const char *s )

-{

-   if (s) {

-      size_t l = strlen(s);

-      char *s2 = (char *) malloc(l + 1);

-      if (s2)

-         strcpy(s2, s);

-      return s2;

-   }

-   else {

-      return NULL;

-   }

-}

-

-/** Wrapper around strtof() */

-float

-_mesa_strtof( const char *s, char **end )

-{

-#if defined(_GNU_SOURCE) && !defined(__CYGWIN__) && !defined(__FreeBSD__)

-   static locale_t loc = NULL;

-   if (!loc) {

-      loc = newlocale(LC_CTYPE_MASK, "C", NULL);

-   }

-   return strtof_l(s, end, loc);

-#elif defined(_ISOC99_SOURCE) || (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE >= 600)

-   return strtof(s, end);

-#else

-   return (float)strtod(s, end);

-#endif

-}

-

-/** 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;

-}

-

-

-/*@}*/

-

-

-/** Wrapper around vsnprintf() */

-int

-_mesa_snprintf( char *str, size_t size, const char *fmt, ... )

-{

-   int r;

-   va_list args;

-   va_start( args, fmt );  

-   r = vsnprintf( str, size, fmt, args );

-   va_end( args );

-   return r;

-}

-

-

-/**********************************************************************/

-/** \name Diagnostics */

-/*@{*/

-

-static void

-output_if_debug(const char *prefixString, const char *outputString,

-                GLboolean newline)

-{

-   static int debug = -1;

-

-   /* Check the MESA_DEBUG environment variable if it hasn't

-    * been checked yet.  We only have to check it once...

-    */

-   if (debug == -1) {

-      char *env = _mesa_getenv("MESA_DEBUG");

-

-      /* In a debug build, we print warning messages *unless*

-       * MESA_DEBUG is 0.  In a non-debug build, we don't

-       * print warning messages *unless* MESA_DEBUG is

-       * set *to any value*.

-       */

-#ifdef DEBUG

-      debug = (env != NULL && atoi(env) == 0) ? 0 : 1;

-#else

-      debug = (env != NULL) ? 1 : 0;

-#endif

-   }

-

-   /* Now only print the string if we're required to do so. */

-   if (debug) {

-      fprintf(stderr, "%s: %s", prefixString, outputString);

-      if (newline)

-         fprintf(stderr, "\n");

-

-#if defined(_WIN32) && !defined(_WIN32_WCE)

-      /* stderr from windows applications without console is not usually 

-       * visible, so communicate with the debugger instead */ 

-      {

-         char buf[4096];

-         _mesa_snprintf(buf, sizeof(buf), "%s: %s%s", prefixString, outputString, newline ? "\n" : "");

-         OutputDebugStringA(buf);

-      }

-#endif

-   }

-}

-

-

-/**

- * Return string version of GL error code.

- */

-static const char *

-error_string( GLenum error )

-{

-   switch (error) {

-   case GL_NO_ERROR:

-      return "GL_NO_ERROR";

-   case GL_INVALID_VALUE:

-      return "GL_INVALID_VALUE";

-   case GL_INVALID_ENUM:

-      return "GL_INVALID_ENUM";

-   case GL_INVALID_OPERATION:

-      return "GL_INVALID_OPERATION";

-   case GL_STACK_OVERFLOW:

-      return "GL_STACK_OVERFLOW";

-   case GL_STACK_UNDERFLOW:

-      return "GL_STACK_UNDERFLOW";

-   case GL_OUT_OF_MEMORY:

-      return "GL_OUT_OF_MEMORY";

-   case GL_TABLE_TOO_LARGE:

-      return "GL_TABLE_TOO_LARGE";

-   case GL_INVALID_FRAMEBUFFER_OPERATION_EXT:

-      return "GL_INVALID_FRAMEBUFFER_OPERATION";

-   default:

-      return "unknown";

-   }

-}

-

-

-/**

- * When a new type of error is recorded, print a message describing

- * previous errors which were accumulated.

- */

-static void

-flush_delayed_errors( struct gl_context *ctx )

-{

-   char s[MAXSTRING];

-

-   if (ctx->ErrorDebugCount) {

-      _mesa_snprintf(s, MAXSTRING, "%d similar %s errors", 

-                     ctx->ErrorDebugCount,

-                     error_string(ctx->ErrorValue));

-

-      output_if_debug("Mesa", s, GL_TRUE);

-

-      ctx->ErrorDebugCount = 0;

-   }

-}

-

-

-/**

- * Report a warning (a recoverable error condition) to stderr if

- * either DEBUG is defined or the MESA_DEBUG env var is set.

- *

- * \param ctx GL context.

- * \param fmtString printf()-like format string.

- */

-void

-_mesa_warning( struct gl_context *ctx, const char *fmtString, ... )

-{

-   char str[MAXSTRING];

-   va_list args;

-   va_start( args, fmtString );  

-   (void) vsnprintf( str, MAXSTRING, fmtString, args );

-   va_end( args );

-   

-   if (ctx)

-      flush_delayed_errors( ctx );

-

-   output_if_debug("Mesa warning", str, GL_TRUE);

-}

-

-

-/**

- * Report an internal implementation problem.

- * Prints the message to stderr via fprintf().

- *

- * \param ctx GL context.

- * \param fmtString problem description string.

- */

-void

-_mesa_problem( const struct gl_context *ctx, const char *fmtString, ... )

-{

-   va_list args;

-   char str[MAXSTRING];

-   (void) ctx;

-

-   va_start( args, fmtString );  

-   vsnprintf( str, MAXSTRING, fmtString, args );

-   va_end( args );

-

-   fprintf(stderr, "Mesa %s implementation error: %s\n", MESA_VERSION_STRING, str);

-   fprintf(stderr, "Please report at bugs.freedesktop.org\n");

-}

-

-

-/**

- * Record an OpenGL state error.  These usually occur when the user

- * passes invalid parameters to a GL function.

- *

- * If debugging is enabled (either at compile-time via the DEBUG macro, or

- * run-time via the MESA_DEBUG environment variable), report the error with

- * _mesa_debug().

- * 

- * \param ctx the GL context.

- * \param error the error value.

- * \param fmtString printf() style format string, followed by optional args

- */

-void

-_mesa_error( struct gl_context *ctx, GLenum error, const char *fmtString, ... )

-{

-   static GLint debug = -1;

-

-   /* Check debug environment variable only once:

-    */

-   if (debug == -1) {

-      const char *debugEnv = _mesa_getenv("MESA_DEBUG");

-

-#ifdef DEBUG

-      if (debugEnv && strstr(debugEnv, "silent"))

-         debug = GL_FALSE;

-      else

-         debug = GL_TRUE;

-#else

-      if (debugEnv)

-         debug = GL_TRUE;

-      else

-         debug = GL_FALSE;

-#endif

-   }

-

-   if (debug) {      

-      if (ctx->ErrorValue == error &&

-          ctx->ErrorDebugFmtString == fmtString) {

-         ctx->ErrorDebugCount++;

-      }

-      else {

-         char s[MAXSTRING], s2[MAXSTRING];

-         va_list args;

-

-         flush_delayed_errors( ctx );

-         

-         va_start(args, fmtString);

-         vsnprintf(s, MAXSTRING, fmtString, args);

-         va_end(args);

-

-         _mesa_snprintf(s2, MAXSTRING, "%s in %s", error_string(error), s);

-         output_if_debug("Mesa: User error", s2, GL_TRUE);

-         

-         ctx->ErrorDebugFmtString = fmtString;

-         ctx->ErrorDebugCount = 0;

-      }

-   }

-

-   _mesa_record_error(ctx, error);

-}

-

-

-/**

- * Report debug information.  Print error message to stderr via fprintf().

- * No-op if DEBUG mode not enabled.

- * 

- * \param ctx GL context.

- * \param fmtString printf()-style format string, followed by optional args.

- */

-void

-_mesa_debug( const struct gl_context *ctx, const char *fmtString, ... )

-{

-#ifdef DEBUG

-   char s[MAXSTRING];

-   va_list args;

-   va_start(args, fmtString);

-   vsnprintf(s, MAXSTRING, fmtString, args);

-   va_end(args);

-   output_if_debug("Mesa", s, GL_FALSE);

-#endif /* DEBUG */

-   (void) ctx;

-   (void) fmtString;

-}

-

-/*@}*/

+/**
+ * \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
+ * Version:  7.1
+ *
+ * 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
+ * BRIAN PAUL 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 "imports.h"
+#include "context.h"
+#include "mtypes.h"
+#include "version.h"
+
+#ifdef _GNU_SOURCE
+#include <locale.h>
+#ifdef __APPLE__
+#include <xlocale.h>
+#endif
+#endif
+
+
+#define MAXSTRING 4000  /* for vsnprintf() */
+
+#ifdef WIN32
+#define vsnprintf _vsnprintf
+#elif defined(__IBMC__) || defined(__IBMCPP__) || ( defined(__VMS) && __CRTL_VER < 70312000 )
+extern int vsnprintf(char *str, size_t count, const char *fmt, va_list arg);
+#ifdef __VMS
+#include "vsnprintf.c"
+#endif
+#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;
+
+   ASSERT( alignment > 0 );
+
+   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) {
+      (void) memset(mem, 0, bytes);
+   }
+
+   return mem;
+#elif defined(_WIN32) && defined(_MSC_VER)
+   void *mem;
+
+   mem = _aligned_malloc(bytes, alignment);
+   if (mem != NULL) {
+      (void) memset(mem, 0, bytes);
+   }
+
+   return mem;
+#else
+   uintptr_t ptr, buf;
+
+   ASSERT( alignment > 0 );
+
+   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.
+ */
+void
+_mesa_align_free(void *ptr)
+{
+#if defined(HAVE_POSIX_MEMALIGN)
+   free(ptr);
+#elif defined(_WIN32) && defined(_MSC_VER)
+   _aligned_free(ptr);
+#else
+   void **cubbyHole = (void **) ((char *) ptr - sizeof(void *));
+   void *realAddr = *cubbyHole;
+   free(realAddr);
+#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);
+   }
+   if (oldBuffer)
+      _mesa_align_free(oldBuffer);
+   return newBuf;
+#endif
+}
+
+
+
+/** Reallocate memory */
+void *
+_mesa_realloc(void *oldBuffer, size_t oldSize, size_t newSize)
+{
+   const size_t copySize = (oldSize < newSize) ? oldSize : newSize;
+   void *newBuffer = malloc(newSize);
+   if (newBuffer && oldBuffer && copySize > 0)
+      memcpy(newBuffer, oldBuffer, copySize);
+   if (oldBuffer)
+      free(oldBuffer);
+   return newBuffer;
+}
+
+/**
+ * Fill memory with a constant 16bit word.
+ * \param dst destination pointer.
+ * \param val value.
+ * \param n number of words.
+ */
+void
+_mesa_memset16( unsigned short *dst, unsigned short val, size_t n )
+{
+   while (n-- > 0)
+      *dst++ = val;
+}
+
+/*@}*/
+
+
+/**********************************************************************/
+/** \name Math */
+/*@{*/
+
+/** Wrapper around sqrt() */
+double
+_mesa_sqrtd(double x)
+{
+   return sqrt(x);
+}
+
+
+/*
+ * A High Speed, Low Precision Square Root
+ * by Paul Lalonde and Robert Dawson
+ * from "Graphics Gems", Academic Press, 1990
+ *
+ * SPARC implementation of a fast square root by table
+ * lookup.
+ * SPARC floating point format is as follows:
+ *
+ * BIT 31 	30 	23 	22 	0
+ *     sign	exponent	mantissa
+ */
+static short sqrttab[0x100];    /* declare table of square roots */
+
+void
+_mesa_init_sqrt_table(void)
+{
+#if defined(USE_IEEE) && !defined(DEBUG)
+   unsigned short i;
+   fi_type fi;     /* to access the bits of a float in  C quickly  */
+                   /* we use a union defined in glheader.h         */
+
+   for(i=0; i<= 0x7f; i++) {
+      fi.i = 0;
+
+      /*
+       * Build a float with the bit pattern i as mantissa
+       * and an exponent of 0, stored as 127
+       */
+
+      fi.i = (i << 16) | (127 << 23);
+      fi.f = _mesa_sqrtd(fi.f);
+
+      /*
+       * Take the square root then strip the first 7 bits of
+       * the mantissa into the table
+       */
+
+      sqrttab[i] = (fi.i & 0x7fffff) >> 16;
+
+      /*
+       * Repeat the process, this time with an exponent of
+       * 1, stored as 128
+       */
+
+      fi.i = 0;
+      fi.i = (i << 16) | (128 << 23);
+      fi.f = sqrt(fi.f);
+      sqrttab[i+0x80] = (fi.i & 0x7fffff) >> 16;
+   }
+#else
+   (void) sqrttab;  /* silence compiler warnings */
+#endif /*HAVE_FAST_MATH*/
+}
+
+
+/**
+ * Single precision square root.
+ */
+float
+_mesa_sqrtf( float x )
+{
+#if defined(USE_IEEE) && !defined(DEBUG)
+   fi_type num;
+                                /* to access the bits of a float in C
+                                 * we use a union from glheader.h     */
+
+   short e;                     /* the exponent */
+   if (x == 0.0F) return 0.0F;  /* check for square root of 0 */
+   num.f = x;
+   e = (num.i >> 23) - 127;     /* get the exponent - on a SPARC the */
+                                /* exponent is stored with 127 added */
+   num.i &= 0x7fffff;           /* leave only the mantissa */
+   if (e & 0x01) num.i |= 0x800000;
+                                /* the exponent is odd so we have to */
+                                /* look it up in the second half of  */
+                                /* the lookup table, so we set the   */
+                                /* high bit                                */
+   e >>= 1;                     /* divide the exponent by two */
+                                /* note that in C the shift */
+                                /* operators are sign preserving */
+                                /* for signed operands */
+   /* Do the table lookup, based on the quaternary mantissa,
+    * then reconstruct the result back into a float
+    */
+   num.i = ((sqrttab[num.i >> 16]) << 16) | ((e + 127) << 23);
+
+   return num.f;
+#else
+   return (float) _mesa_sqrtd((double) x);
+#endif
+}
+
+
+/**
+ inv_sqrt - A single precision 1/sqrt routine for IEEE format floats.
+ written by Josh Vanderhoof, based on newsgroup posts by James Van Buskirk
+ and Vesa Karvonen.
+*/
+float
+_mesa_inv_sqrtf(float n)
+{
+#if defined(USE_IEEE) && !defined(DEBUG)
+        float r0, x0, y0;
+        float r1, x1, y1;
+        float r2, x2, y2;
+#if 0 /* not used, see below -BP */
+        float r3, x3, y3;
+#endif
+        fi_type u;
+        unsigned int magic;
+
+        /*
+         Exponent part of the magic number -
+
+         We want to:
+         1. subtract the bias from the exponent,
+         2. negate it
+         3. divide by two (rounding towards -inf)
+         4. add the bias back
+
+         Which is the same as subtracting the exponent from 381 and dividing
+         by 2.
+
+         floor(-(x - 127) / 2) + 127 = floor((381 - x) / 2)
+        */
+
+        magic = 381 << 23;
+
+        /*
+         Significand part of magic number -
+
+         With the current magic number, "(magic - u.i) >> 1" will give you:
+
+         for 1 <= u.f <= 2: 1.25 - u.f / 4
+         for 2 <= u.f <= 4: 1.00 - u.f / 8
+
+         This isn't a bad approximation of 1/sqrt.  The maximum difference from
+         1/sqrt will be around .06.  After three Newton-Raphson iterations, the
+         maximum difference is less than 4.5e-8.  (Which is actually close
+         enough to make the following bias academic...)
+
+         To get a better approximation you can add a bias to the magic
+         number.  For example, if you subtract 1/2 of the maximum difference in
+         the first approximation (.03), you will get the following function:
+
+         for 1 <= u.f <= 2:    1.22 - u.f / 4
+         for 2 <= u.f <= 3.76: 0.97 - u.f / 8
+         for 3.76 <= u.f <= 4: 0.72 - u.f / 16
+         (The 3.76 to 4 range is where the result is < .5.)
+
+         This is the closest possible initial approximation, but with a maximum
+         error of 8e-11 after three NR iterations, it is still not perfect.  If
+         you subtract 0.0332281 instead of .03, the maximum error will be
+         2.5e-11 after three NR iterations, which should be about as close as
+         is possible.
+
+         for 1 <= u.f <= 2:    1.2167719 - u.f / 4
+         for 2 <= u.f <= 3.73: 0.9667719 - u.f / 8
+         for 3.73 <= u.f <= 4: 0.7167719 - u.f / 16
+
+        */
+
+        magic -= (int)(0.0332281 * (1 << 25));
+
+        u.f = n;
+        u.i = (magic - u.i) >> 1;
+
+        /*
+         Instead of Newton-Raphson, we use Goldschmidt's algorithm, which
+         allows more parallelism.  From what I understand, the parallelism
+         comes at the cost of less precision, because it lets error
+         accumulate across iterations.
+        */
+        x0 = 1.0f;
+        y0 = 0.5f * n;
+        r0 = u.f;
+
+        x1 = x0 * r0;
+        y1 = y0 * r0 * r0;
+        r1 = 1.5f - y1;
+
+        x2 = x1 * r1;
+        y2 = y1 * r1 * r1;
+        r2 = 1.5f - y2;
+
+#if 1
+        return x2 * r2;  /* we can stop here, and be conformant -BP */
+#else
+        x3 = x2 * r2;
+        y3 = y2 * r2 * r2;
+        r3 = 1.5f - y3;
+
+        return x3 * r3;
+#endif
+#else
+        return (float) (1.0 / sqrt(n));
+#endif
+}
+
+#ifndef __GNUC__
+/**
+ * Find the first bit set in a word.
+ */
+int
+_mesa_ffs(int32_t i)
+{
+#if (defined(_WIN32) ) || defined(__IBMC__) || defined(__IBMCPP__)
+   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;
+#else
+   return ffs(i);
+#endif
+}
+
+
+/**
+ * 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
+_mesa_ffsll(int64_t val)
+{
+   int bit;
+
+   assert(sizeof(val) == 8);
+
+   bit = _mesa_ffs((int32_t)val);
+   if (bit != 0)
+      return bit;
+
+   bit = _mesa_ffs((int32_t)(val >> 32));
+   if (bit != 0)
+      return 32 + bit;
+
+   return 0;
+}
+
+
+#if ((_GNUC__ == 3 && __GNUC_MINOR__ < 4) || __GNUC__ < 4)
+/**
+ * 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
+#endif
+
+
+/**
+ * Convert a 4-byte float to a 2-byte half float.
+ * Based on code from:
+ * http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/008786.html
+ */
+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 < -24) {
+         /* this maps to 0 */
+         /* m = 0; - already set */
+         e = 0;
+      }
+      else if (new_exp < -14) {
+         /* this maps to a denorm */
+         unsigned int exp_val = (unsigned int) (-14 - new_exp); /* 2^-exp_val*/
+         e = 0;
+         switch (exp_val) {
+            case 0:
+               _mesa_warning(NULL,
+                   "float_to_half: logical error in denorm creation!\n");
+               /* m = 0; - already set */
+               break;
+            case 1: m = 512 + (flt_m >> 14); break;
+            case 2: m = 256 + (flt_m >> 15); break;
+            case 3: m = 128 + (flt_m >> 16); break;
+            case 4: m = 64 + (flt_m >> 17); break;
+            case 5: m = 32 + (flt_m >> 18); break;
+            case 6: m = 16 + (flt_m >> 19); break;
+            case 7: m = 8 + (flt_m >> 20); break;
+            case 8: m = 4 + (flt_m >> 21); break;
+            case 9: m = 2 + (flt_m >> 22); break;
+            case 10: m = 1; break;
+         }
+      }
+      else if (new_exp > 15) {
+         /* map this value to infinity */
+         /* m = 0; - already set */
+         e = 31;
+      }
+      else {
+         /* regular */
+         e = new_exp + 15;
+         m = flt_m >> 13;
+      }
+   }
+
+   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 Sort & Search */
+/*@{*/
+
+/**
+ * Wrapper for bsearch().
+ */
+void *
+_mesa_bsearch( const void *key, const void *base, size_t nmemb, size_t size, 
+               int (*compar)(const void *, const void *) )
+{
+#if defined(_WIN32_WCE)
+   void *mid;
+   int cmp;
+   while (nmemb) {
+      nmemb >>= 1;
+      mid = (char *)base + nmemb * size;
+      cmp = (*compar)(key, mid);
+      if (cmp == 0)
+	 return mid;
+      if (cmp > 0) {
+	 base = (char *)mid + size;
+	 --nmemb;
+      }
+   }
+   return NULL;
+#else
+   return bsearch(key, base, nmemb, size, compar);
+#endif
+}
+
+/*@}*/
+
+
+/**********************************************************************/
+/** \name Environment vars */
+/*@{*/
+
+/**
+ * Wrapper for getenv().
+ */
+char *
+_mesa_getenv( const char *var )
+{
+#if defined(_XBOX) || defined(_WIN32_WCE)
+   return NULL;
+#else
+   return getenv(var);
+#endif
+}
+
+/*@}*/
+
+
+/**********************************************************************/
+/** \name String */
+/*@{*/
+
+/**
+ * Implemented using malloc() and strcpy.
+ * Note that NULL is handled accordingly.
+ */
+char *
+_mesa_strdup( const char *s )
+{
+   if (s) {
+      size_t l = strlen(s);
+      char *s2 = (char *) malloc(l + 1);
+      if (s2)
+         strcpy(s2, s);
+      return s2;
+   }
+   else {
+      return NULL;
+   }
+}
+
+/** Wrapper around strtof() */
+float
+_mesa_strtof( const char *s, char **end )
+{
+#if defined(_GNU_SOURCE) && !defined(__CYGWIN__) && !defined(__FreeBSD__)
+   static locale_t loc = NULL;
+   if (!loc) {
+      loc = newlocale(LC_CTYPE_MASK, "C", NULL);
+   }
+   return strtof_l(s, end, loc);
+#elif defined(_ISOC99_SOURCE) || (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE >= 600)
+   return strtof(s, end);
+#else
+   return (float)strtod(s, end);
+#endif
+}
+
+/** 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;
+}
+
+
+/*@}*/
+
+
+/** Wrapper around vsnprintf() */
+int
+_mesa_snprintf( char *str, size_t size, const char *fmt, ... )
+{
+   int r;
+   va_list args;
+   va_start( args, fmt );  
+   r = vsnprintf( str, size, fmt, args );
+   va_end( args );
+   return r;
+}
+
+
+/**********************************************************************/
+/** \name Diagnostics */
+/*@{*/
+
+static void
+output_if_debug(const char *prefixString, const char *outputString,
+                GLboolean newline)
+{
+   static int debug = -1;
+
+   /* Check the MESA_DEBUG environment variable if it hasn't
+    * been checked yet.  We only have to check it once...
+    */
+   if (debug == -1) {
+      char *env = _mesa_getenv("MESA_DEBUG");
+
+      /* In a debug build, we print warning messages *unless*
+       * MESA_DEBUG is 0.  In a non-debug build, we don't
+       * print warning messages *unless* MESA_DEBUG is
+       * set *to any value*.
+       */
+#ifdef DEBUG
+      debug = (env != NULL && atoi(env) == 0) ? 0 : 1;
+#else
+      debug = (env != NULL) ? 1 : 0;
+#endif
+   }
+
+   /* Now only print the string if we're required to do so. */
+   if (debug) {
+      fprintf(stderr, "%s: %s", prefixString, outputString);
+      if (newline)
+         fprintf(stderr, "\n");
+
+#if defined(_WIN32) && !defined(_WIN32_WCE)
+      /* stderr from windows applications without console is not usually 
+       * visible, so communicate with the debugger instead */ 
+      {
+         char buf[4096];
+         _mesa_snprintf(buf, sizeof(buf), "%s: %s%s", prefixString, outputString, newline ? "\n" : "");
+         OutputDebugStringA(buf);
+      }
+#endif
+   }
+}
+
+
+/**
+ * Return string version of GL error code.
+ */
+static const char *
+error_string( GLenum error )
+{
+   switch (error) {
+   case GL_NO_ERROR:
+      return "GL_NO_ERROR";
+   case GL_INVALID_VALUE:
+      return "GL_INVALID_VALUE";
+   case GL_INVALID_ENUM:
+      return "GL_INVALID_ENUM";
+   case GL_INVALID_OPERATION:
+      return "GL_INVALID_OPERATION";
+   case GL_STACK_OVERFLOW:
+      return "GL_STACK_OVERFLOW";
+   case GL_STACK_UNDERFLOW:
+      return "GL_STACK_UNDERFLOW";
+   case GL_OUT_OF_MEMORY:
+      return "GL_OUT_OF_MEMORY";
+   case GL_TABLE_TOO_LARGE:
+      return "GL_TABLE_TOO_LARGE";
+   case GL_INVALID_FRAMEBUFFER_OPERATION_EXT:
+      return "GL_INVALID_FRAMEBUFFER_OPERATION";
+   default:
+      return "unknown";
+   }
+}
+
+
+/**
+ * When a new type of error is recorded, print a message describing
+ * previous errors which were accumulated.
+ */
+static void
+flush_delayed_errors( struct gl_context *ctx )
+{
+   char s[MAXSTRING];
+
+   if (ctx->ErrorDebugCount) {
+      _mesa_snprintf(s, MAXSTRING, "%d similar %s errors", 
+                     ctx->ErrorDebugCount,
+                     error_string(ctx->ErrorValue));
+
+      output_if_debug("Mesa", s, GL_TRUE);
+
+      ctx->ErrorDebugCount = 0;
+   }
+}
+
+
+/**
+ * Report a warning (a recoverable error condition) to stderr if
+ * either DEBUG is defined or the MESA_DEBUG env var is set.
+ *
+ * \param ctx GL context.
+ * \param fmtString printf()-like format string.
+ */
+void
+_mesa_warning( struct gl_context *ctx, const char *fmtString, ... )
+{
+   char str[MAXSTRING];
+   va_list args;
+   va_start( args, fmtString );  
+   (void) vsnprintf( str, MAXSTRING, fmtString, args );
+   va_end( args );
+   
+   if (ctx)
+      flush_delayed_errors( ctx );
+
+   output_if_debug("Mesa warning", str, GL_TRUE);
+}
+
+
+/**
+ * Report an internal implementation problem.
+ * Prints the message to stderr via fprintf().
+ *
+ * \param ctx GL context.
+ * \param fmtString problem description string.
+ */
+void
+_mesa_problem( const struct gl_context *ctx, const char *fmtString, ... )
+{
+   va_list args;
+   char str[MAXSTRING];
+   (void) ctx;
+
+   va_start( args, fmtString );  
+   vsnprintf( str, MAXSTRING, fmtString, args );
+   va_end( args );
+
+   fprintf(stderr, "Mesa %s implementation error: %s\n", MESA_VERSION_STRING, str);
+   fprintf(stderr, "Please report at bugs.freedesktop.org\n");
+}
+
+
+/**
+ * Record an OpenGL state error.  These usually occur when the user
+ * passes invalid parameters to a GL function.
+ *
+ * If debugging is enabled (either at compile-time via the DEBUG macro, or
+ * run-time via the MESA_DEBUG environment variable), report the error with
+ * _mesa_debug().
+ * 
+ * \param ctx the GL context.
+ * \param error the error value.
+ * \param fmtString printf() style format string, followed by optional args
+ */
+void
+_mesa_error( struct gl_context *ctx, GLenum error, const char *fmtString, ... )
+{
+   static GLint debug = -1;
+
+   /* Check debug environment variable only once:
+    */
+   if (debug == -1) {
+      const char *debugEnv = _mesa_getenv("MESA_DEBUG");
+
+#ifdef DEBUG
+      if (debugEnv && strstr(debugEnv, "silent"))
+         debug = GL_FALSE;
+      else
+         debug = GL_TRUE;
+#else
+      if (debugEnv)
+         debug = GL_TRUE;
+      else
+         debug = GL_FALSE;
+#endif
+   }
+
+   if (debug) {      
+      if (ctx->ErrorValue == error &&
+          ctx->ErrorDebugFmtString == fmtString) {
+         ctx->ErrorDebugCount++;
+      }
+      else {
+         char s[MAXSTRING], s2[MAXSTRING];
+         va_list args;
+
+         flush_delayed_errors( ctx );
+         
+         va_start(args, fmtString);
+         vsnprintf(s, MAXSTRING, fmtString, args);
+         va_end(args);
+
+         _mesa_snprintf(s2, MAXSTRING, "%s in %s", error_string(error), s);
+         output_if_debug("Mesa: User error", s2, GL_TRUE);
+         
+         ctx->ErrorDebugFmtString = fmtString;
+         ctx->ErrorDebugCount = 0;
+      }
+   }
+
+   _mesa_record_error(ctx, error);
+}
+
+
+/**
+ * Report debug information.  Print error message to stderr via fprintf().
+ * No-op if DEBUG mode not enabled.
+ * 
+ * \param ctx GL context.
+ * \param fmtString printf()-style format string, followed by optional args.
+ */
+void
+_mesa_debug( const struct gl_context *ctx, const char *fmtString, ... )
+{
+#ifdef DEBUG
+   char s[MAXSTRING];
+   va_list args;
+   va_start(args, fmtString);
+   vsnprintf(s, MAXSTRING, fmtString, args);
+   va_end(args);
+   output_if_debug("Mesa", s, GL_FALSE);
+#endif /* DEBUG */
+   (void) ctx;
+   (void) fmtString;
+}
+
+/*@}*/