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