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    if (oldBuffer)
 222       free(oldBuffer);
 223    return newBuffer;
 224 }
 225
 226 /*@}*/
 227
 228
 229 /**********************************************************************/
 230 /** \name Math */
 231 /*@{*/
 232
 233
 234 #ifndef __GNUC__
 235 /**
 236  * Find the first bit set in a word.
 237  */
 238 int
 239 ffs(int i)
 240 {
 241    register int bit = 0;
 242    if (i != 0) {
 243       if ((i & 0xffff) == 0) {
 244          bit += 16;
 245          i >>= 16;
 246       }
 247       if ((i & 0xff) == 0) {
 248          bit += 8;
 249          i >>= 8;
 250       }
 251       if ((i & 0xf) == 0) {
 252          bit += 4;
 253          i >>= 4;
 254       }
 255       while ((i & 1) == 0) {
 256          bit++;
 257          i >>= 1;
 258       }
 259       bit++;
 260    }
 261    return bit;
 262 }
 263
 264
 265 /**
 266  * Find position of first bit set in given value.
 267  * XXX Warning: this function can only be used on 64-bit systems!
 268  * \return  position of least-significant bit set, starting at 1, return zero
 269  *          if no bits set.
 270  */
 271 int
 272 ffsll(long long int val)
 273 {
 274    int bit;
 275
 276    assert(sizeof(val) == 8);
 277
 278    bit = ffs((int) val);
 279    if (bit != 0)
 280       return bit;
 281
 282    bit = ffs((int) (val >> 32));
 283    if (bit != 0)
 284       return 32 + bit;
 285
 286    return 0;
 287 }
 288 #endif /* __GNUC__ */
 289
 290
 291 #if !defined(__GNUC__) ||\
 292    ((__GNUC__ * 100 + __GNUC_MINOR__) < 304) /* Not gcc 3.4 or later */
 293 /**
 294  * Return number of bits set in given GLuint.
 295  */
 296 unsigned int
 297 _mesa_bitcount(unsigned int n)
 298 {
 299    unsigned int bits;
 300    for (bits = 0; n > 0; n = n >> 1) {
 301       bits += (n & 1);
 302    }
 303    return bits;
 304 }
 305
 306 /**
 307  * Return number of bits set in given 64-bit uint.
 308  */
 309 unsigned int
 310 _mesa_bitcount_64(uint64_t n)
 311 {
 312    unsigned int bits;
 313    for (bits = 0; n > 0; n = n >> 1) {
 314       bits += (n & 1);
 315    }
 316    return bits;
 317 }
 318 #endif
 319
 320
 321 /**
 322  * Convert a 4-byte float to a 2-byte half float.
 323  * Based on code from:
 324  * http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/008786.html
 325  */
 326 GLhalfARB
 327 _mesa_float_to_half(float val)
 328 {
 329    const fi_type fi = {val};
 330    const int flt_m = fi.i & 0x7fffff;
 331    const int flt_e = (fi.i >> 23) & 0xff;
 332    const int flt_s = (fi.i >> 31) & 0x1;
 333    int s, e, m = 0;
 334    GLhalfARB result;
 335
 336    /* sign bit */
 337    s = flt_s;
 338
 339    /* handle special cases */
 340    if ((flt_e == 0) && (flt_m == 0)) {
 341       /* zero */
 342       /* m = 0; - already set */
 343       e = 0;
 344    }
 345    else if ((flt_e == 0) && (flt_m != 0)) {
 346       /* denorm -- denorm float maps to 0 half */
 347       /* m = 0; - already set */
 348       e = 0;
 349    }
 350    else if ((flt_e == 0xff) && (flt_m == 0)) {
 351       /* infinity */
 352       /* m = 0; - already set */
 353       e = 31;
 354    }
 355    else if ((flt_e == 0xff) && (flt_m != 0)) {
 356       /* NaN */
 357       m = 1;
 358       e = 31;
 359    }
 360    else {
 361       /* regular number */
 362       const int new_exp = flt_e - 127;
 363       if (new_exp < -24) {
 364          /* this maps to 0 */
 365          /* m = 0; - already set */
 366          e = 0;
 367       }
 368       else if (new_exp < -14) {
 369          /* this maps to a denorm */
 370          unsigned int exp_val = (unsigned int) (-14 - new_exp); /* 2^-exp_val*/
 371          e = 0;
 372          switch (exp_val) {
 373             case 0:
 374                _mesa_warning(NULL,
 375                    "float_to_half: logical error in denorm creation!\n");
 376                /* m = 0; - already set */
 377                break;
 378             case 1: m = 512 + (flt_m >> 14); break;
 379             case 2: m = 256 + (flt_m >> 15); break;
 380             case 3: m = 128 + (flt_m >> 16); break;
 381             case 4: m = 64 + (flt_m >> 17); break;
 382             case 5: m = 32 + (flt_m >> 18); break;
 383             case 6: m = 16 + (flt_m >> 19); break;
 384             case 7: m = 8 + (flt_m >> 20); break;
 385             case 8: m = 4 + (flt_m >> 21); break;
 386             case 9: m = 2 + (flt_m >> 22); break;
 387             case 10: m = 1; break;
 388          }
 389       }
 390       else if (new_exp > 15) {
 391          /* map this value to infinity */
 392          /* m = 0; - already set */
 393          e = 31;
 394       }
 395       else {
 396          /* regular */
 397          e = new_exp + 15;
 398          m = flt_m >> 13;
 399       }
 400    }
 401
 402    result = (s << 15) | (e << 10) | m;
 403    return result;
 404 }
 405
 406
 407 /**
 408  * Convert a 2-byte half float to a 4-byte float.
 409  * Based on code from:
 410  * http://www.opengl.org/discussion_boards/ubb/Forum3/HTML/008786.html
 411  */
 412 float
 413 _mesa_half_to_float(GLhalfARB val)
 414 {
 415    /* XXX could also use a 64K-entry lookup table */
 416    const int m = val & 0x3ff;
 417    const int e = (val >> 10) & 0x1f;
 418    const int s = (val >> 15) & 0x1;
 419    int flt_m, flt_e, flt_s;
 420    fi_type fi;
 421    float result;
 422
 423    /* sign bit */
 424    flt_s = s;
 425
 426    /* handle special cases */
 427    if ((e == 0) && (m == 0)) {
 428       /* zero */
 429       flt_m = 0;
 430       flt_e = 0;
 431    }
 432    else if ((e == 0) && (m != 0)) {
 433       /* denorm -- denorm half will fit in non-denorm single */
 434       const float half_denorm = 1.0f / 16384.0f; /* 2^-14 */
 435       float mantissa = ((float) (m)) / 1024.0f;
 436       float sign = s ? -1.0f : 1.0f;
 437       return sign * mantissa * half_denorm;
 438    }
 439    else if ((e == 31) && (m == 0)) {
 440       /* infinity */
 441       flt_e = 0xff;
 442       flt_m = 0;
 443    }
 444    else if ((e == 31) && (m != 0)) {
 445       /* NaN */
 446       flt_e = 0xff;
 447       flt_m = 1;
 448    }
 449    else {
 450       /* regular */
 451       flt_e = e + 112;
 452       flt_m = m << 13;
 453    }
 454
 455    fi.i = (flt_s << 31) | (flt_e << 23) | flt_m;
 456    result = fi.f;
 457    return result;
 458 }
 459
 460 /*@}*/
 461
 462
 463 /**********************************************************************/
 464 /** \name Sort & Search */
 465 /*@{*/
 466
 467 /**
 468  * Wrapper for bsearch().
 469  */
 470 void *
 471 _mesa_bsearch( const void *key, const void *base, size_t nmemb, size_t size,
 472                int (*compar)(const void *, const void *) )
 473 {
 474 #if defined(_WIN32_WCE)
 475    void *mid;
 476    int cmp;
 477    while (nmemb) {
 478       nmemb >>= 1;
 479       mid = (char *)base + nmemb * size;
 480       cmp = (*compar)(key, mid);
 481       if (cmp == 0)
 482          return mid;
 483       if (cmp > 0) {
 484          base = (char *)mid + size;
 485          --nmemb;
 486       }
 487    }
 488    return NULL;
 489 #else
 490    return bsearch(key, base, nmemb, size, compar);
 491 #endif
 492 }
 493
 494 /*@}*/
 495
 496
 497 /**********************************************************************/
 498 /** \name Environment vars */
 499 /*@{*/
 500
 501 /**
 502  * Wrapper for getenv().
 503  */
 504 char *
 505 _mesa_getenv( const char *var )
 506 {
 507 #if defined(_XBOX) || defined(_WIN32_WCE)
 508    return NULL;
 509 #else
 510    return getenv(var);
 511 #endif
 512 }
 513
 514 /*@}*/
 515
 516
 517 /**********************************************************************/
 518 /** \name String */
 519 /*@{*/
 520
 521 /**
 522  * Implemented using malloc() and strcpy.
 523  * Note that NULL is handled accordingly.
 524  */
 525 char *
 526 _mesa_strdup( const char *s )
 527 {
 528    if (s) {
 529       size_t l = strlen(s);
 530       char *s2 = malloc(l + 1);
 531       if (s2)
 532          strcpy(s2, s);
 533       return s2;
 534    }
 535    else {
 536       return NULL;
 537    }
 538 }
 539
 540 /** Wrapper around strtof() */
 541 float
 542 _mesa_strtof( const char *s, char **end )
 543 {
 544 #if defined(_GNU_SOURCE) && !defined(__CYGWIN__) && !defined(__FreeBSD__) && \
 545    !defined(ANDROID) && !defined(__HAIKU__) && !defined(__UCLIBC__)
 546    static locale_t loc = NULL;
 547    if (!loc) {
 548       loc = newlocale(LC_CTYPE_MASK, "C", NULL);
 549    }
 550    return strtof_l(s, end, loc);
 551 #elif defined(_ISOC99_SOURCE) || (defined(_XOPEN_SOURCE) && _XOPEN_SOURCE >= 600)
 552    return strtof(s, end);
 553 #else
 554    return (float)strtod(s, end);
 555 #endif
 556 }
 557
 558 /** Compute simple checksum/hash for a string */
 559 unsigned int
 560 _mesa_str_checksum(const char *str)
 561 {
 562    /* This could probably be much better */
 563    unsigned int sum, i;
 564    const char *c;
 565    sum = i = 1;
 566    for (c = str; *c; c++, i++)
 567       sum += *c * (i % 100);
 568    return sum + i;
 569 }
 570
 571
 572 /*@}*/
 573
 574
 575 /** Needed due to #ifdef's, above. */
 576 int
 577 _mesa_vsnprintf(char *str, size_t size, const char *fmt, va_list args)
 578 {
 579    return vsnprintf( str, size, fmt, args);
 580 }
 581
 582 /** Wrapper around vsnprintf() */
 583 int
 584 _mesa_snprintf( char *str, size_t size, const char *fmt, ... )
 585 {
 586    int r;
 587    va_list args;
 588    va_start( args, fmt );
 589    r = vsnprintf( str, size, fmt, args );
 590    va_end( args );
 591    return r;
 592 }
 593
 594