src/mesa/main/imports.c

   1 /**
   2  * \file imports.c
   3  * Standard C library function wrappers.
   4  *
   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,
   8  * etc.
   9  *
  10  * Some drivers will want to override/replace this file with something
  11  * specialized, but that'll be rare.
  12  *
  13  * Eventually, I want to move roll the glheader.h file into this.
  14  *
  15  * \todo Functions still needed:
  16  * - scanf
  17  * - qsort
  18  * - rand and RAND_MAX
  19  */
  20
  21 /*
  22  * Mesa 3-D graphics library
  23  * Version:  7.1
  24  *
  25  * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
  26  *
  27  * Permission is hereby granted, free of charge, to any person obtaining a
  28  * copy of this software and associated documentation files (the "Software"),
  29  * to deal in the Software without restriction, including without limitation
  30  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  31  * and/or sell copies of the Software, and to permit persons to whom the
  32  * Software is furnished to do so, subject to the following conditions:
  33  *
  34  * The above copyright notice and this permission notice shall be included
  35  * in all copies or substantial portions of the Software.
  36  *
  37  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  38  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  39  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  40  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  41  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  42  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  43  */
  44
  45
  46
  47 #include "imports.h"
  48 #include "context.h"
  49 #include "mtypes.h"
  50 #include "version.h"
  51
  52 #ifdef _GNU_SOURCE
  53 #include <locale.h>
  54 #ifdef __APPLE__
  55 #include <xlocale.h>
  56 #endif
  57 #endif
  58
  59
  60 #ifdef _WIN32
  61 #define vsnprintf _vsnprintf
  62 #elif defined(__IBMC__) || defined(__IBMCPP__) || ( defined(__VMS) && __CRTL_VER < 70312000 )
  63 extern int vsnprintf(char *str, size_t count, const char *fmt, va_list arg);
  64 #ifdef __VMS
  65 #include "vsnprintf.c"
  66 #endif
  67 #endif
  68
  69 /**********************************************************************/
  70 /** \name Memory */
  71 /*@{*/
  72
  73 /**
  74  * Allocate aligned memory.
  75  *
  76  * \param bytes number of bytes to allocate.
  77  * \param alignment alignment (must be greater than zero).
  78  *
  79  * Allocates extra memory to accommodate rounding up the address for
  80  * alignment and to record the real malloc address.
  81  *
  82  * \sa _mesa_align_free().
  83  */
  84 void *
  85 _mesa_align_malloc(size_t bytes, unsigned long alignment)
  86 {
  87 #if defined(HAVE_POSIX_MEMALIGN)
  88    void *mem;
  89    int err = posix_memalign(& mem, alignment, bytes);
  90    if (err)
  91       return NULL;
  92    return mem;
  93 #elif defined(_WIN32) && defined(_MSC_VER)
  94    return _aligned_malloc(bytes, alignment);
  95 #else
  96    uintptr_t ptr, buf;
  97
  98    ASSERT( alignment > 0 );
  99
 100    ptr = malloc(bytes + alignment + sizeof(void *));
 101    if (!ptr)
 102       return NULL;
 103
 104    buf = (ptr + alignment + sizeof(void *)) & ~(uintptr_t)(alignment - 1);
 105    *(uintptr_t *)(buf - sizeof(void *)) = ptr;
 106
 107 #ifdef DEBUG
 108    /* mark the non-aligned area */
 109    while ( ptr < buf - sizeof(void *) ) {
 110       *(unsigned long *)ptr = 0xcdcdcdcd;
 111       ptr += sizeof(unsigned long);
 112    }
 113 #endif
 114
 115    return (void *) buf;
 116 #endif /* defined(HAVE_POSIX_MEMALIGN) */
 117 }
 118
 119 /**
 120  * Same as _mesa_align_malloc(), but using calloc(1, ) instead of
 121  * malloc()
 122  */
 123 void *
 124 _mesa_align_calloc(size_t bytes, unsigned long alignment)
 125 {
 126 #if defined(HAVE_POSIX_MEMALIGN)
 127    void *mem;
 128
 129    mem = _mesa_align_malloc(bytes, alignment);
 130    if (mem != NULL) {
 131       (void) memset(mem, 0, bytes);
 132    }
 133
 134    return mem;
 135 #elif defined(_WIN32) && defined(_MSC_VER)
 136    void *mem;
 137
 138    mem = _aligned_malloc(bytes, alignment);
 139    if (mem != NULL) {
 140       (void) memset(mem, 0, bytes);
 141    }
 142
 143    return mem;
 144 #else
 145    uintptr_t ptr, buf;
 146
 147    ASSERT( alignment > 0 );
 148
 149    ptr = calloc(1, bytes + alignment + sizeof(void *));
 150    if (!ptr)
 151       return NULL;
 152
 153    buf = (ptr + alignment + sizeof(void *)) & ~(uintptr_t)(alignment - 1);
 154    *(uintptr_t *)(buf - sizeof(void *)) = ptr;
 155
 156 #ifdef DEBUG
 157    /* mark the non-aligned area */
 158    while ( ptr < buf - sizeof(void *) ) {
 159       *(unsigned long *)ptr = 0xcdcdcdcd;
 160       ptr += sizeof(unsigned long);
 161    }
 162 #endif
 163
 164    return (void *)buf;
 165 #endif /* defined(HAVE_POSIX_MEMALIGN) */
 166 }
 167
 168 /**
 169  * Free memory which was allocated with either _mesa_align_malloc()
 170  * or _mesa_align_calloc().
 171  * \param ptr pointer to the memory to be freed.
 172  * The actual address to free is stored in the word immediately before the
 173  * address the client sees.
 174  */
 175 void
 176 _mesa_align_free(void *ptr)
 177 {
 178 #if defined(HAVE_POSIX_MEMALIGN)
 179    free(ptr);
 180 #elif defined(_WIN32) && defined(_MSC_VER)
 181    _aligned_free(ptr);
 182 #else
 183    void **cubbyHole = (void **) ((char *) ptr - sizeof(void *));
 184    void *realAddr = *cubbyHole;
 185    free(realAddr);
 186 #endif /* defined(HAVE_POSIX_MEMALIGN) */
 187 }
 188
 189 /**
 190  * Reallocate memory, with alignment.
 191  */
 192 void *
 193 _mesa_align_realloc(void *oldBuffer, size_t oldSize, size_t newSize,
 194                     unsigned long alignment)
 195 {
 196 #if defined(_WIN32) && defined(_MSC_VER)
 197    (void) oldSize;
 198    return _aligned_realloc(oldBuffer, newSize, alignment);
 199 #else
 200    const size_t copySize = (oldSize < newSize) ? oldSize : newSize;
 201    void *newBuf = _mesa_align_malloc(newSize, alignment);
 202    if (newBuf && oldBuffer && copySize > 0) {
 203       memcpy(newBuf, oldBuffer, copySize);
 204    }
 205    if (oldBuffer)
 206       _mesa_align_free(oldBuffer);
 207    return newBuf;
 208 #endif
 209 }
 210
 211
 212
 213 /** Reallocate memory */
 214 void *
 215 _mesa_realloc(void *oldBuffer, size_t oldSize, size_t newSize)
 216 {
 217    const size_t copySize = (oldSize < newSize) ? oldSize : newSize;
 218    void *newBuffer = malloc(newSize);
 219    if (newBuffer && oldBuffer && copySize > 0)
 220       memcpy(newBuffer, oldBuffer, copySize);
 221    free(oldBuffer);
 222    return newBuffer;
 223 }
 224
 225 /*@}*/
 226
 227
 228 /**********************************************************************/
 229 /** \name Math */
 230 /*@{*/
 231
 232
 233 #ifndef __GNUC__
 234 /**
 235  * Find the first bit set in a word.
 236  */
 237 int
 238 ffs(int i)
 239 {
 240    register int bit = 0;
 241    if (i != 0) {
 242       if ((i & 0xffff) == 0) {
 243          bit += 16;
 244          i >>= 16;
 245       }
 246       if ((i & 0xff) == 0) {
 247          bit += 8;
 248          i >>= 8;
 249       }
 250       if ((i & 0xf) == 0) {
 251          bit += 4;
 252          i >>= 4;
 253       }
 254       while ((i & 1) == 0) {
 255          bit++;
 256          i >>= 1;
 257       }
 258       bit++;
 259    }
 260    return bit;
 261 }
 262
 263
 264 /**
 265  * Find position of first bit set in given value.
 266  * XXX Warning: this function can only be used on 64-bit systems!
 267  * \return  position of least-significant bit set, starting at 1, return zero
 268  *          if no bits set.
 269  */
 270 int
 271 ffsll(long long int val)
 272 {
 273    int bit;
 274
 275    assert(sizeof(val) == 8);
 276
 277    bit = ffs((int) val);
 278    if (bit != 0)
 279       return bit;
 280
 281    bit = ffs((int) (val >> 32));
 282    if (bit != 0)
 283       return 32 + bit;
 284
 285    return 0;
 286 }
 287 #endif /* __GNUC__ */
 288
 289
 290 #if !defined(__GNUC__) ||\
 291    ((__GNUC__ * 100 + __GNUC_MINOR__) < 304) /* Not gcc 3.4 or later */
 292 /**
 293  * Return number of bits set in given GLuint.
 294  */
 295 unsigned int
 296 _mesa_bitcount(unsigned int n)
 297 {
 298    unsigned int bits;
 299    for (bits = 0; n > 0; n = n >> 1) {
 300       bits += (n & 1);
 301    }
 302    return bits;
 303 }
 304
 305 /**
 306  * Return number of bits set in given 64-bit uint.
 307  */
 308 unsigned int
 309 _mesa_bitcount_64(uint64_t n)
 310 {
 311    unsigned int bits;
 312    for (bits = 0; n > 0; n = n >> 1) {
 313       bits += (n & 1);
 314    }
 315    return bits;
 316 }
 317 #endif
 318
 319
 320 /**
 321  * Convert a 4-byte float to a 2-byte half float.
 322  * Based on code from:
 323  * http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/008786.html
 324  */
 325 GLhalfARB
 326 _mesa_float_to_half(float val)
 327 {
 328    const fi_type fi = {val};
 329    const int flt_m = fi.i & 0x7fffff;
 330    const int flt_e = (fi.i >> 23) & 0xff;
 331    const int flt_s = (fi.i >> 31) & 0x1;
 332    int s, e, m = 0;
 333    GLhalfARB result;
 334
 335    /* sign bit */
 336    s = flt_s;
 337
 338    /* handle special cases */
 339    if ((flt_e == 0) && (flt_m == 0)) {
 340       /* zero */
 341       /* m = 0; - already set */
 342       e = 0;
 343    }
 344    else if ((flt_e == 0) && (flt_m != 0)) {
 345       /* denorm -- denorm float maps to 0 half */
 346       /* m = 0; - already set */
 347       e = 0;
 348    }
 349    else if ((flt_e == 0xff) && (flt_m == 0)) {
 350       /* infinity */
 351       /* m = 0; - already set */
 352       e = 31;
 353    }
 354    else if ((flt_e == 0xff) && (flt_m != 0)) {
 355       /* NaN */
 356       m = 1;
 357       e = 31;
 358    }
 359    else {
 360       /* regular number */
 361       const int new_exp = flt_e - 127;
 362       if (new_exp < -24) {
 363          /* this maps to 0 */
 364          /* m = 0; - already set */
 365          e = 0;
 366       }
 367       else if (new_exp < -14) {
 368          /* this maps to a denorm */
 369          unsigned int exp_val = (unsigned int) (-14 - new_exp); /* 2^-exp_val*/
 370          e = 0;
 371          switch (exp_val) {
 372             case 0:
 373                _mesa_warning(NULL,
 374                    "float_to_half: logical error in denorm creation!\n");
 375                /* m = 0; - already set */
 376                break;
 377             case 1: m = 512 + (flt_m >> 14); break;
 378             case 2: m = 256 + (flt_m >> 15); break;
 379             case 3: m = 128 + (flt_m >> 16); break;
 380             case 4: m = 64 + (flt_m >> 17); break;
 381             case 5: m = 32 + (flt_m >> 18); break;
 382             case 6: m = 16 + (flt_m >> 19); break;
 383             case 7: m = 8 + (flt_m >> 20); break;
 384             case 8: m = 4 + (flt_m >> 21); break;
 385             case 9: m = 2 + (flt_m >> 22); break;
 386             case 10: m = 1; break;
 387          }
 388       }
 389       else if (new_exp > 15) {
 390          /* map this value to infinity */
 391          /* m = 0; - already set */
 392          e = 31;
 393       }
 394       else {
 395          /* regular */
 396          e = new_exp + 15;
 397          m = flt_m >> 13;
 398       }
 399    }
 400
 401    result = (s << 15) | (e << 10) | m;
 402    return result;
 403 }
 404
 405
 406 /**
 407  * Convert a 2-byte half float to a 4-byte float.
 408  * Based on code from:
 409  * http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/008786.html
 410  */
 411 float
 412 _mesa_half_to_float(GLhalfARB val)
 413 {
 414    /* XXX could also use a 64K-entry lookup table */
 415    const int m = val & 0x3ff;
 416    const int e = (val >> 10) & 0x1f;
 417    const int s = (val >> 15) & 0x1;
 418    int flt_m, flt_e, flt_s;
 419    fi_type fi;
 420    float result;
 421
 422    /* sign bit */
 423    flt_s = s;
 424
 425    /* handle special cases */
 426    if ((e == 0) && (m == 0)) {
 427       /* zero */
 428       flt_m = 0;
 429       flt_e = 0;
 430    }
 431    else if ((e == 0) && (m != 0)) {
 432       /* denorm -- denorm half will fit in non-denorm single */
 433       const float half_denorm = 1.0f / 16384.0f; /* 2^-14 */
 434       float mantissa = ((float) (m)) / 1024.0f;
 435       float sign = s ? -1.0f : 1.0f;
 436       return sign * mantissa * half_denorm;
 437    }
 438    else if ((e == 31) && (m == 0)) {
 439       /* infinity */
 440       flt_e = 0xff;
 441       flt_m = 0;
 442    }
 443    else if ((e == 31) && (m != 0)) {
 444       /* NaN */
 445       flt_e = 0xff;
 446       flt_m = 1;
 447    }
 448    else {
 449       /* regular */
 450       flt_e = e + 112;
 451       flt_m = m << 13;
 452    }
 453
 454    fi.i = (flt_s << 31) | (flt_e << 23) | flt_m;
 455    result = fi.f;
 456    return result;
 457 }
 458
 459 /*@}*/
 460
 461
 462 /**********************************************************************/
 463 /** \name Sort & Search */
 464 /*@{*/
 465
 466 /**
 467  * Wrapper for bsearch().
 468  */
 469 void *
 470 _mesa_bsearch( const void *key, const void *base, size_t nmemb, size_t size,
 471                int (*compar)(const void *, const void *) )
 472 {
 473 #if defined(_WIN32_WCE)
 474    void *mid;
 475    int cmp;
 476    while (nmemb) {
 477       nmemb >>= 1;
 478       mid = (char *)base + nmemb * size;
 479       cmp = (*compar)(key, mid);
 480       if (cmp == 0)
 481          return mid;
 482       if (cmp > 0) {
 483          base = (char *)mid + size;
 484          --nmemb;
 485       }
 486    }
 487    return NULL;
 488 #else
 489    return bsearch(key, base, nmemb, size, compar);
 490 #endif
 491 }
 492
 493 /*@}*/
 494
 495
 496 /**********************************************************************/
 497 /** \name Environment vars */
 498 /*@{*/
 499
 500 /**
 501  * Wrapper for getenv().
 502  */
 503 char *
 504 _mesa_getenv( const char *var )
 505 {
 506 #if defined(_XBOX) || defined(_WIN32_WCE)
 507    return NULL;
 508 #else
 509    return getenv(var);
 510 #endif
 511 }
 512
 513 /*@}*/
 514
 515
 516 /**********************************************************************/
 517 /** \name String */
 518 /*@{*/
 519
 520 /**
 521  * Implemented using malloc() and strcpy.
 522  * Note that NULL is handled accordingly.
 523  */
 524 char *
 525 _mesa_strdup( const char *s )
 526 {
 527    if (s) {
 528       size_t l = strlen(s);
 529       char *s2 = malloc(l + 1);
 530       if (s2)
 531          strcpy(s2, s);
 532       return s2;
 533    }
 534    else {
 535       return NULL;
 536    }
 537 }
 538
 539 /** Wrapper around strtof() */
 540 float
 541 _mesa_strtof( const char *s, char **end )
 542 {
 543 #if defined(_GNU_SOURCE) && !defined(__CYGWIN__) && !defined(__FreeBSD__) && \
 544    !defined(ANDROID) && !defined(__HAIKU__) && !defined(__UCLIBC__)
 545    static locale_t loc = NULL;
 546    if (!loc) {
 547       loc = newlocale(LC_CTYPE_MASK, "C", NULL);
 548    }
 549    return strtof_l(s, end, loc);
 550 #elif defined(_ISOC99_SOURCE) || (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE >= 600)
 551    return strtof(s, end);
 552 #else
 553    return (float)strtod(s, end);
 554 #endif
 555 }
 556
 557 /** Compute simple checksum/hash for a string */
 558 unsigned int
 559 _mesa_str_checksum(const char *str)
 560 {
 561    /* This could probably be much better */
 562    unsigned int sum, i;
 563    const char *c;
 564    sum = i = 1;
 565    for (c = str; *c; c++, i++)
 566       sum += *c * (i % 100);
 567    return sum + i;
 568 }
 569
 570
 571 /*@}*/
 572
 573
 574 /** Needed due to #ifdef's, above. */
 575 int
 576 _mesa_vsnprintf(char *str, size_t size, const char *fmt, va_list args)
 577 {
 578    return vsnprintf( str, size, fmt, args);
 579 }
 580
 581 /** Wrapper around vsnprintf() */
 582 int
 583 _mesa_snprintf( char *str, size_t size, const char *fmt, ... )
 584 {
 585    int r;
 586    va_list args;
 587    va_start( args, fmt );
 588    r = vsnprintf( str, size, fmt, args );
 589    va_end( args );
 590    return r;
 591 }
 592
 593