Alc/helpers.c

   1 /**
   2  * OpenAL cross platform audio library
   3  * Copyright (C) 2011 by authors.
   4  * This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU Library General Public
   6  *  License as published by the Free Software Foundation; either
   7  *  version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  *  License along with this library; if not, write to the
  16  *  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  *  Boston, MA  02111-1307, USA.
  18  * Or go to http://www.gnu.org/copyleft/lgpl.html
  19  */
  20
  21 #include "config.h"
  22
  23 #include <stdlib.h>
  24 #include <time.h>
  25 #include <errno.h>
  26 #include <stdarg.h>
  27 #ifdef HAVE_DLFCN_H
  28 #include <dlfcn.h>
  29 #endif
  30 #ifdef HAVE_CPUID_H
  31 #include <cpuid.h>
  32 #endif
  33 #ifdef HAVE_FLOAT_H
  34 #include <float.h>
  35 #endif
  36 #ifdef HAVE_IEEEFP_H
  37 #include <ieeefp.h>
  38 #endif
  39
  40 #if defined(HAVE_GUIDDEF_H) || defined(HAVE_INITGUID_H)
  41 #define INITGUID
  42 #include <windows.h>
  43 #ifdef HAVE_GUIDDEF_H
  44 #include <guiddef.h>
  45 #else
  46 #include <initguid.h>
  47 #endif
  48
  49 DEFINE_GUID(KSDATAFORMAT_SUBTYPE_PCM,        0x00000001, 0x0000, 0x0010, 0x80,0x00, 0x00,0xaa,0x00,0x38,0x9b,0x71);
  50 DEFINE_GUID(KSDATAFORMAT_SUBTYPE_IEEE_FLOAT, 0x00000003, 0x0000, 0x0010, 0x80,0x00, 0x00,0xaa,0x00,0x38,0x9b,0x71);
  51
  52 DEFINE_GUID(IID_IDirectSoundNotify,   0xb0210783, 0x89cd, 0x11d0, 0xaf,0x08, 0x00,0xa0,0xc9,0x25,0xcd,0x16);
  53
  54 DEFINE_GUID(CLSID_MMDeviceEnumerator, 0xbcde0395, 0xe52f, 0x467c, 0x8e,0x3d, 0xc4,0x57,0x92,0x91,0x69,0x2e);
  55 DEFINE_GUID(IID_IMMDeviceEnumerator,  0xa95664d2, 0x9614, 0x4f35, 0xa7,0x46, 0xde,0x8d,0xb6,0x36,0x17,0xe6);
  56 DEFINE_GUID(IID_IAudioClient,         0x1cb9ad4c, 0xdbfa, 0x4c32, 0xb1,0x78, 0xc2,0xf5,0x68,0xa7,0x03,0xb2);
  57 DEFINE_GUID(IID_IAudioRenderClient,   0xf294acfc, 0x3146, 0x4483, 0xa7,0xbf, 0xad,0xdc,0xa7,0xc2,0x60,0xe2);
  58
  59 #ifdef HAVE_MMDEVAPI
  60 #include <devpropdef.h>
  61
  62 DEFINE_DEVPROPKEY(DEVPKEY_Device_FriendlyName, 0xa45c254e, 0xdf1c, 0x4efd, 0x80,0x20, 0x67,0xd1,0x46,0xa8,0x50,0xe0, 14);
  63 #endif
  64
  65 #endif
  66
  67 #include "alMain.h"
  68
  69 ALuint CPUCapFlags = 0;
  70
  71
  72 void FillCPUCaps(ALuint capfilter)
  73 {
  74     ALuint caps = 0;
  75
  76 #if defined(__i386__) || defined(__x86_64__) || defined(_M_IX86) || defined(_M_X64)
  77 /* FIXME: We really should get this for all available CPUs in case different
  78  * CPUs have different caps (is that possible on one machine?). */
  79 #ifdef HAVE_CPUID_H
  80     union {
  81         unsigned int regs[4];
  82         char str[sizeof(unsigned int[4])];
  83     } cpuinf[3];
  84
  85     if(!__get_cpuid(0, &cpuinf[0].regs[0], &cpuinf[0].regs[1], &cpuinf[0].regs[2], &cpuinf[0].regs[3]))
  86         ERR("Failed to get CPUID\n");
  87     else
  88     {
  89         unsigned int maxfunc = cpuinf[0].regs[0];
  90         unsigned int maxextfunc = 0;
  91
  92         if(__get_cpuid(0x80000000, &cpuinf[0].regs[0], &cpuinf[0].regs[1], &cpuinf[0].regs[2], &cpuinf[0].regs[3]))
  93             maxextfunc = cpuinf[0].regs[0];
  94         TRACE("Detected max CPUID function: 0x%x (ext. 0x%x)\n", maxfunc, maxextfunc);
  95
  96         TRACE("Vendor ID: \"%.4s%.4s%.4s\"\n", cpuinf[0].str+4, cpuinf[0].str+12, cpuinf[0].str+8);
  97         if(maxextfunc >= 0x80000004 &&
  98            __get_cpuid(0x80000002, &cpuinf[0].regs[0], &cpuinf[0].regs[1], &cpuinf[0].regs[2], &cpuinf[0].regs[3]) &&
  99            __get_cpuid(0x80000003, &cpuinf[1].regs[0], &cpuinf[1].regs[1], &cpuinf[1].regs[2], &cpuinf[1].regs[3]) &&
 100            __get_cpuid(0x80000004, &cpuinf[2].regs[0], &cpuinf[2].regs[1], &cpuinf[2].regs[2], &cpuinf[2].regs[3]))
 101             TRACE("Name: \"%.16s%.16s%.16s\"\n", cpuinf[0].str, cpuinf[1].str, cpuinf[2].str);
 102
 103         if(maxfunc >= 1 &&
 104            __get_cpuid(1, &cpuinf[0].regs[0], &cpuinf[0].regs[1], &cpuinf[0].regs[2], &cpuinf[0].regs[3]))
 105         {
 106 #ifdef bit_SSE
 107             if((cpuinf[0].regs[3]&bit_SSE))
 108                 caps |= CPU_CAP_SSE;
 109 #endif
 110         }
 111     }
 112 #endif
 113 #endif
 114 #ifdef HAVE_NEON
 115     /* Assume Neon support if compiled with it */
 116     caps |= CPU_CAP_NEON;
 117 #endif
 118
 119     TRACE("Got caps:%s%s%s\n", ((caps&CPU_CAP_SSE)?((capfilter&CPU_CAP_SSE)?" SSE":" (SSE)"):""),
 120                                ((caps&CPU_CAP_NEON)?((capfilter&CPU_CAP_NEON)?" Neon":" (Neon)"):""),
 121                                ((!caps)?" -none-":""));
 122     CPUCapFlags = caps & capfilter;
 123 }
 124
 125
 126 void *al_malloc(size_t alignment, size_t size)
 127 {
 128 #if defined(HAVE_ALIGNED_ALLOC)
 129     size = (size+(alignment-1))&~(alignment-1);
 130     return aligned_alloc(alignment, size);
 131 #elif defined(HAVE_POSIX_MEMALIGN)
 132     void *ret;
 133     if(posix_memalign(&ret, alignment, size) == 0)
 134         return ret;
 135     return NULL;
 136 #elif defined(HAVE__ALIGNED_MALLOC)
 137     return _aligned_malloc(size, alignment);
 138 #else
 139     char *ret = malloc(size+alignment);
 140     if(ret != NULL)
 141     {
 142         *(ret++) = 0x00;
 143         while(((ALintptrEXT)ret&(alignment-1)) != 0)
 144             *(ret++) = 0x55;
 145     }
 146     return ret;
 147 #endif
 148 }
 149
 150 void *al_calloc(size_t alignment, size_t size)
 151 {
 152     void *ret = al_malloc(alignment, size);
 153     if(ret) memset(ret, 0, size);
 154     return ret;
 155 }
 156
 157 void al_free(void *ptr)
 158 {
 159 #if defined(HAVE_ALIGNED_ALLOC) || defined(HAVE_POSIX_MEMALIGN)
 160     free(ptr);
 161 #elif defined(HAVE__ALIGNED_MALLOC)
 162     _aligned_free(ptr);
 163 #else
 164     if(ptr != NULL)
 165     {
 166         char *finder = ptr;
 167         do {
 168             --finder;
 169         } while(*finder == 0x55);
 170         free(finder);
 171     }
 172 #endif
 173 }
 174
 175
 176 #if (defined(HAVE___CONTROL87_2) || defined(HAVE__CONTROLFP)) && (defined(__x86_64__) || defined(_M_X64))
 177 /* Win64 doesn't allow us to set the precision control. */
 178 #undef _MCW_PC
 179 #define _MCW_PC 0
 180 #endif
 181
 182 void SetMixerFPUMode(FPUCtl *ctl)
 183 {
 184 #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
 185     unsigned short fpuState;
 186     __asm__ __volatile__("fnstcw %0" : "=m" (*&fpuState));
 187     ctl->state = fpuState;
 188     fpuState &= ~0x300; /* clear precision to single */
 189     fpuState |=  0xC00; /* set round-to-zero */
 190     __asm__ __volatile__("fldcw %0" : : "m" (*&fpuState));
 191 #ifdef HAVE_SSE
 192     if((CPUCapFlags&CPU_CAP_SSE))
 193     {
 194         int sseState;
 195         __asm__ __volatile__("stmxcsr %0" : "=m" (*&sseState));
 196         ctl->sse_state = sseState;
 197         sseState |= 0x0C00; /* set round-to-zero */
 198         sseState |= 0x8000; /* set flush-to-zero */
 199         __asm__ __volatile__("ldmxcsr %0" : : "m" (*&sseState));
 200     }
 201 #endif
 202 #elif defined(HAVE___CONTROL87_2)
 203     int mode;
 204     __control87_2(0, 0, &ctl->state, &ctl->sse_state);
 205     __control87_2(_RC_CHOP|_PC_24, _MCW_RC|_MCW_PC, &mode, NULL);
 206 #ifdef HAVE_SSE
 207     if((CPUCapFlags&CPU_CAP_SSE))
 208         __control87_2(_RC_CHOP|_DN_FLUSH, _MCW_RC|_MCW_DN, NULL, &mode);
 209 #endif
 210 #elif defined(HAVE__CONTROLFP)
 211     ctl->state = _controlfp(0, 0);
 212     (void)_controlfp(_RC_CHOP|_PC_24, _MCW_RC|_MCW_PC);
 213 #elif defined(HAVE_FESETROUND)
 214     ctl->state = fegetround();
 215 #ifdef FE_TOWARDZERO
 216     fesetround(FE_TOWARDZERO);
 217 #endif
 218 #endif
 219 }
 220
 221 void RestoreFPUMode(const FPUCtl *ctl)
 222 {
 223 #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
 224     unsigned short fpuState = ctl->state;
 225     __asm__ __volatile__("fldcw %0" : : "m" (*&fpuState));
 226 #ifdef HAVE_SSE
 227     if((CPUCapFlags&CPU_CAP_SSE))
 228         __asm__ __volatile__("ldmxcsr %0" : : "m" (*&ctl->sse_state));
 229 #endif
 230 #elif defined(HAVE___CONTROL87_2)
 231     int mode;
 232     __control87_2(ctl->state, _MCW_RC|_MCW_PC, &mode, NULL);
 233 #ifdef HAVE_SSE
 234     if((CPUCapFlags&CPU_CAP_SSE))
 235         __control87_2(ctl->sse_state, _MCW_RC|_MCW_DN, NULL, &mode);
 236 #endif
 237 #elif defined(HAVE__CONTROLFP)
 238     _controlfp(ctl->state, _MCW_RC|_MCW_PC);
 239 #elif defined(HAVE_FESETROUND)
 240     fesetround(ctl->state);
 241 #endif
 242 }
 243
 244
 245 #ifdef _WIN32
 246 void pthread_once(pthread_once_t *once, void (*callback)(void))
 247 {
 248     LONG ret;
 249     while((ret=InterlockedExchange(once, 1)) == 1)
 250         sched_yield();
 251     if(ret == 0)
 252         callback();
 253     InterlockedExchange(once, 2);
 254 }
 255
 256
 257 int pthread_key_create(pthread_key_t *key, void (*callback)(void*))
 258 {
 259     *key = TlsAlloc();
 260     if(callback)
 261         InsertUIntMapEntry(&TlsDestructor, *key, callback);
 262     return 0;
 263 }
 264
 265 int pthread_key_delete(pthread_key_t key)
 266 {
 267     InsertUIntMapEntry(&TlsDestructor, key, NULL);
 268     TlsFree(key);
 269     return 0;
 270 }
 271
 272 void *pthread_getspecific(pthread_key_t key)
 273 { return TlsGetValue(key); }
 274
 275 int pthread_setspecific(pthread_key_t key, void *val)
 276 {
 277     TlsSetValue(key, val);
 278     return 0;
 279 }
 280
 281
 282 void *LoadLib(const char *name)
 283 { return LoadLibraryA(name); }
 284 void CloseLib(void *handle)
 285 { FreeLibrary((HANDLE)handle); }
 286 void *GetSymbol(void *handle, const char *name)
 287 {
 288     void *ret;
 289
 290     ret = (void*)GetProcAddress((HANDLE)handle, name);
 291     if(ret == NULL)
 292         ERR("Failed to load %s\n", name);
 293     return ret;
 294 }
 295
 296 WCHAR *strdupW(const WCHAR *str)
 297 {
 298     const WCHAR *n;
 299     WCHAR *ret;
 300     size_t len;
 301
 302     n = str;
 303     while(*n) n++;
 304     len = n - str;
 305
 306     ret = calloc(sizeof(WCHAR), len+1);
 307     if(ret != NULL)
 308         memcpy(ret, str, sizeof(WCHAR)*len);
 309     return ret;
 310 }
 311
 312 #else
 313
 314 #include <pthread.h>
 315 #ifdef HAVE_PTHREAD_NP_H
 316 #include <pthread_np.h>
 317 #endif
 318 #include <sched.h>
 319
 320 void InitializeCriticalSection(CRITICAL_SECTION *cs)
 321 {
 322     pthread_mutexattr_t attrib;
 323     int ret;
 324
 325     ret = pthread_mutexattr_init(&attrib);
 326     assert(ret == 0);
 327
 328     ret = pthread_mutexattr_settype(&attrib, PTHREAD_MUTEX_RECURSIVE);
 329 #ifdef HAVE_PTHREAD_NP_H
 330     if(ret != 0)
 331         ret = pthread_mutexattr_setkind_np(&attrib, PTHREAD_MUTEX_RECURSIVE);
 332 #endif
 333     assert(ret == 0);
 334     ret = pthread_mutex_init(cs, &attrib);
 335     assert(ret == 0);
 336
 337     pthread_mutexattr_destroy(&attrib);
 338 }
 339 void DeleteCriticalSection(CRITICAL_SECTION *cs)
 340 {
 341     int ret;
 342     ret = pthread_mutex_destroy(cs);
 343     assert(ret == 0);
 344 }
 345 void EnterCriticalSection(CRITICAL_SECTION *cs)
 346 {
 347     int ret;
 348     ret = pthread_mutex_lock(cs);
 349     assert(ret == 0);
 350 }
 351 void LeaveCriticalSection(CRITICAL_SECTION *cs)
 352 {
 353     int ret;
 354     ret = pthread_mutex_unlock(cs);
 355     assert(ret == 0);
 356 }
 357
 358 /* NOTE: This wrapper isn't quite accurate as it returns an ALuint, as opposed
 359  * to the expected DWORD. Both are defined as unsigned 32-bit types, however.
 360  * Additionally, Win32 is supposed to measure the time since Windows started,
 361  * as opposed to the actual time. */
 362 ALuint timeGetTime(void)
 363 {
 364 #if _POSIX_TIMERS > 0
 365     struct timespec ts;
 366     int ret = -1;
 367
 368 #if defined(_POSIX_MONOTONIC_CLOCK) && (_POSIX_MONOTONIC_CLOCK >= 0)
 369 #if _POSIX_MONOTONIC_CLOCK == 0
 370     static int hasmono = 0;
 371     if(hasmono > 0 || (hasmono == 0 &&
 372                        (hasmono=sysconf(_SC_MONOTONIC_CLOCK)) > 0))
 373 #endif
 374         ret = clock_gettime(CLOCK_MONOTONIC, &ts);
 375 #endif
 376     if(ret != 0)
 377         ret = clock_gettime(CLOCK_REALTIME, &ts);
 378     assert(ret == 0);
 379
 380     return ts.tv_nsec/1000000 + ts.tv_sec*1000;
 381 #else
 382     struct timeval tv;
 383     int ret;
 384
 385     ret = gettimeofday(&tv, NULL);
 386     assert(ret == 0);
 387
 388     return tv.tv_usec/1000 + tv.tv_sec*1000;
 389 #endif
 390 }
 391
 392 void Sleep(ALuint t)
 393 {
 394     struct timespec tv, rem;
 395     tv.tv_nsec = (t*1000000)%1000000000;
 396     tv.tv_sec = t/1000;
 397
 398     while(nanosleep(&tv, &rem) == -1 && errno == EINTR)
 399         tv = rem;
 400 }
 401
 402 #ifdef HAVE_DLFCN_H
 403
 404 void *LoadLib(const char *name)
 405 {
 406     const char *err;
 407     void *handle;
 408
 409     dlerror();
 410     handle = dlopen(name, RTLD_NOW);
 411     if((err=dlerror()) != NULL)
 412         handle = NULL;
 413     return handle;
 414 }
 415 void CloseLib(void *handle)
 416 { dlclose(handle); }
 417 void *GetSymbol(void *handle, const char *name)
 418 {
 419     const char *err;
 420     void *sym;
 421
 422     dlerror();
 423     sym = dlsym(handle, name);
 424     if((err=dlerror()) != NULL)
 425     {
 426         WARN("Failed to load %s: %s\n", name, err);
 427         sym = NULL;
 428     }
 429     return sym;
 430 }
 431
 432 #endif
 433 #endif
 434
 435
 436 void al_print(const char *func, const char *fmt, ...)
 437 {
 438     char str[256];
 439     int i;
 440
 441     i = snprintf(str, sizeof(str), "AL lib: %s: ", func);
 442     if(i < (int)sizeof(str) && i > 0)
 443     {
 444         va_list ap;
 445         va_start(ap, fmt);
 446         vsnprintf(str+i, sizeof(str)-i, fmt, ap);
 447         va_end(ap);
 448     }
 449     str[sizeof(str)-1] = 0;
 450
 451     fprintf(LogFile, "%s", str);
 452     fflush(LogFile);
 453 }
 454
 455
 456 void SetRTPriority(void)
 457 {
 458     ALboolean failed = AL_FALSE;
 459
 460 #ifdef _WIN32
 461     if(RTPrioLevel > 0)
 462         failed = !SetThreadPriority(GetCurrentThread(), THREAD_PRIORITY_TIME_CRITICAL);
 463 #elif defined(HAVE_PTHREAD_SETSCHEDPARAM) && !defined(__OpenBSD__)
 464     if(RTPrioLevel > 0)
 465     {
 466         struct sched_param param;
 467         /* Use the minimum real-time priority possible for now (on Linux this
 468          * should be 1 for SCHED_RR) */
 469         param.sched_priority = sched_get_priority_min(SCHED_RR);
 470         failed = !!pthread_setschedparam(pthread_self(), SCHED_RR, &param);
 471     }
 472 #else
 473     /* Real-time priority not available */
 474     failed = (RTPrioLevel>0);
 475 #endif
 476     if(failed)
 477         ERR("Failed to set priority level for thread\n");
 478 }
 479
 480
 481 static void Lock(volatile ALenum *l)
 482 {
 483     while(ExchangeInt(l, AL_TRUE) == AL_TRUE)
 484         sched_yield();
 485 }
 486
 487 static void Unlock(volatile ALenum *l)
 488 {
 489     ExchangeInt(l, AL_FALSE);
 490 }
 491
 492 void RWLockInit(RWLock *lock)
 493 {
 494     lock->read_count = 0;
 495     lock->write_count = 0;
 496     lock->read_lock = AL_FALSE;
 497     lock->read_entry_lock = AL_FALSE;
 498     lock->write_lock = AL_FALSE;
 499 }
 500
 501 void ReadLock(RWLock *lock)
 502 {
 503     Lock(&lock->read_entry_lock);
 504     Lock(&lock->read_lock);
 505     if(IncrementRef(&lock->read_count) == 1)
 506         Lock(&lock->write_lock);
 507     Unlock(&lock->read_lock);
 508     Unlock(&lock->read_entry_lock);
 509 }
 510
 511 void ReadUnlock(RWLock *lock)
 512 {
 513     if(DecrementRef(&lock->read_count) == 0)
 514         Unlock(&lock->write_lock);
 515 }
 516
 517 void WriteLock(RWLock *lock)
 518 {
 519     if(IncrementRef(&lock->write_count) == 1)
 520         Lock(&lock->read_lock);
 521     Lock(&lock->write_lock);
 522 }
 523
 524 void WriteUnlock(RWLock *lock)
 525 {
 526     Unlock(&lock->write_lock);
 527     if(DecrementRef(&lock->write_count) == 0)
 528         Unlock(&lock->read_lock);
 529 }
 530
 531
 532 void InitUIntMap(UIntMap *map, ALsizei limit)
 533 {
 534     map->array = NULL;
 535     map->size = 0;
 536     map->maxsize = 0;
 537     map->limit = limit;
 538     RWLockInit(&map->lock);
 539 }
 540
 541 void ResetUIntMap(UIntMap *map)
 542 {
 543     WriteLock(&map->lock);
 544     free(map->array);
 545     map->array = NULL;
 546     map->size = 0;
 547     map->maxsize = 0;
 548     WriteUnlock(&map->lock);
 549 }
 550
 551 ALenum InsertUIntMapEntry(UIntMap *map, ALuint key, ALvoid *value)
 552 {
 553     ALsizei pos = 0;
 554
 555     WriteLock(&map->lock);
 556     if(map->size > 0)
 557     {
 558         ALsizei low = 0;
 559         ALsizei high = map->size - 1;
 560         while(low < high)
 561         {
 562             ALsizei mid = low + (high-low)/2;
 563             if(map->array[mid].key < key)
 564                 low = mid + 1;
 565             else
 566                 high = mid;
 567         }
 568         if(map->array[low].key < key)
 569             low++;
 570         pos = low;
 571     }
 572
 573     if(pos == map->size || map->array[pos].key != key)
 574     {
 575         if(map->size == map->limit)
 576         {
 577             WriteUnlock(&map->lock);
 578             return AL_OUT_OF_MEMORY;
 579         }
 580
 581         if(map->size == map->maxsize)
 582         {
 583             ALvoid *temp = NULL;
 584             ALsizei newsize;
 585
 586             newsize = (map->maxsize ? (map->maxsize<<1) : 4);
 587             if(newsize >= map->maxsize)
 588                 temp = realloc(map->array, newsize*sizeof(map->array[0]));
 589             if(!temp)
 590             {
 591                 WriteUnlock(&map->lock);
 592                 return AL_OUT_OF_MEMORY;
 593             }
 594             map->array = temp;
 595             map->maxsize = newsize;
 596         }
 597
 598         if(pos < map->size)
 599             memmove(&map->array[pos+1], &map->array[pos],
 600                     (map->size-pos)*sizeof(map->array[0]));
 601         map->size++;
 602     }
 603     map->array[pos].key = key;
 604     map->array[pos].value = value;
 605     WriteUnlock(&map->lock);
 606
 607     return AL_NO_ERROR;
 608 }
 609
 610 ALvoid *RemoveUIntMapKey(UIntMap *map, ALuint key)
 611 {
 612     ALvoid *ptr = NULL;
 613     WriteLock(&map->lock);
 614     if(map->size > 0)
 615     {
 616         ALsizei low = 0;
 617         ALsizei high = map->size - 1;
 618         while(low < high)
 619         {
 620             ALsizei mid = low + (high-low)/2;
 621             if(map->array[mid].key < key)
 622                 low = mid + 1;
 623             else
 624                 high = mid;
 625         }
 626         if(map->array[low].key == key)
 627         {
 628             ptr = map->array[low].value;
 629             if(low < map->size-1)
 630                 memmove(&map->array[low], &map->array[low+1],
 631                         (map->size-1-low)*sizeof(map->array[0]));
 632             map->size--;
 633         }
 634     }
 635     WriteUnlock(&map->lock);
 636     return ptr;
 637 }
 638
 639 ALvoid *LookupUIntMapKey(UIntMap *map, ALuint key)
 640 {
 641     ALvoid *ptr = NULL;
 642     ReadLock(&map->lock);
 643     if(map->size > 0)
 644     {
 645         ALsizei low = 0;
 646         ALsizei high = map->size - 1;
 647         while(low < high)
 648         {
 649             ALsizei mid = low + (high-low)/2;
 650             if(map->array[mid].key < key)
 651                 low = mid + 1;
 652             else
 653                 high = mid;
 654         }
 655         if(map->array[low].key == key)
 656             ptr = map->array[low].value;
 657     }
 658     ReadUnlock(&map->lock);
 659     return ptr;
 660 }