src/egl/main/egldriver.c

   1 /**
   2  * Functions for choosing and opening/loading device drivers.
   3  */
   4
   5
   6 #include <assert.h>
   7 #include <string.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include "eglconfig.h"
  11 #include "eglcontext.h"
  12 #include "egldefines.h"
  13 #include "egldisplay.h"
  14 #include "egldriver.h"
  15 #include "eglglobals.h"
  16 #include "egllog.h"
  17 #include "eglmisc.h"
  18 #include "eglmode.h"
  19 #include "eglscreen.h"
  20 #include "eglstring.h"
  21 #include "eglsurface.h"
  22 #include "eglimage.h"
  23
  24 #if defined(_EGL_PLATFORM_POSIX)
  25 #include <dlfcn.h>
  26 #include <sys/types.h>
  27 #include <dirent.h>
  28 #endif
  29
  30
  31 /**
  32  * Wrappers for dlopen/dlclose()
  33  */
  34 #if defined(_EGL_PLATFORM_WINDOWS)
  35
  36
  37 /* XXX Need to decide how to do dynamic name lookup on Windows */
  38 static const char DefaultDriverName[] = "TBD";
  39
  40 typedef HMODULE lib_handle;
  41
  42 static HMODULE
  43 open_library(const char *filename)
  44 {
  45    return LoadLibrary(filename);
  46 }
  47
  48 static void
  49 close_library(HMODULE lib)
  50 {
  51    FreeLibrary(lib);
  52 }
  53
  54
  55 static const char *
  56 library_suffix(void)
  57 {
  58    return "dll";
  59 }
  60
  61
  62 static EGLBoolean
  63 make_library_path(char *buf, unsigned int size, const char *name)
  64 {
  65    EGLBoolean need_suffix;
  66    const char *suffix = ".dll";
  67    int ret;
  68
  69    need_suffix = (strchr(name, '.') == NULL);
  70    ret = snprintf(buf, size, "%s%s", name, (need_suffix) ? suffix : "");
  71
  72    return ((unsigned int) ret < size);
  73 }
  74
  75
  76 #elif defined(_EGL_PLATFORM_POSIX)
  77
  78
  79 static const char DefaultDriverName[] = "egl_glx";
  80
  81 typedef void * lib_handle;
  82
  83 static void *
  84 open_library(const char *filename)
  85 {
  86    return dlopen(filename, RTLD_LAZY);
  87 }
  88
  89 static void
  90 close_library(void *lib)
  91 {
  92    dlclose(lib);
  93 }
  94
  95
  96 static const char *
  97 library_suffix(void)
  98 {
  99    return "so";
 100 }
 101
 102
 103 static EGLBoolean
 104 make_library_path(char *buf, unsigned int size, const char *name)
 105 {
 106    EGLBoolean need_dir, need_suffix;
 107    const char *suffix = ".so";
 108    int ret;
 109
 110    need_dir = (strchr(name, '/') == NULL);
 111    need_suffix = (strchr(name, '.') == NULL);
 112
 113    ret = snprintf(buf, size, "%s%s%s",
 114          (need_dir) ? _EGL_DRIVER_SEARCH_DIR"/" : "", name,
 115          (need_suffix) ? suffix : "");
 116
 117    return ((unsigned int) ret < size);
 118 }
 119
 120
 121 #else /* _EGL_PLATFORM_NO_OS */
 122
 123 static const char DefaultDriverName[] = "builtin";
 124
 125 typedef void *lib_handle;
 126
 127 static INLINE void *
 128 open_library(const char *filename)
 129 {
 130    return (void *) filename;
 131 }
 132
 133 static INLINE void
 134 close_library(void *lib)
 135 {
 136 }
 137
 138
 139 static const char *
 140 library_suffix(void)
 141 {
 142    return NULL;
 143 }
 144
 145
 146 static EGLBoolean
 147 make_library_path(char *buf, unsigned int size, const char *name)
 148 {
 149    int ret = snprintf(buf, size, name);
 150    return ((unsigned int) ret < size);
 151 }
 152
 153
 154 #endif
 155
 156
 157 #define NUM_PROBE_CACHE_SLOTS 8
 158 static struct {
 159    EGLint keys[NUM_PROBE_CACHE_SLOTS];
 160    const void *values[NUM_PROBE_CACHE_SLOTS];
 161 } _eglProbeCache;
 162
 163
 164 /**
 165  * Open the named driver and find its bootstrap function: _eglMain().
 166  */
 167 static _EGLMain_t
 168 _eglOpenLibrary(const char *driverPath, lib_handle *handle)
 169 {
 170    lib_handle lib;
 171    _EGLMain_t mainFunc = NULL;
 172    const char *error = "unknown error";
 173
 174    assert(driverPath);
 175
 176    _eglLog(_EGL_DEBUG, "dlopen(%s)", driverPath);
 177    lib = open_library(driverPath);
 178
 179 #if defined(_EGL_PLATFORM_WINDOWS)
 180    /* XXX untested */
 181    if (lib)
 182       mainFunc = (_EGLMain_t) GetProcAddress(lib, "_eglMain");
 183 #elif defined(_EGL_PLATFORM_POSIX)
 184    if (lib) {
 185       mainFunc = (_EGLMain_t) dlsym(lib, "_eglMain");
 186       if (!mainFunc)
 187          error = dlerror();
 188    }
 189    else {
 190       error = dlerror();
 191    }
 192 #else /* _EGL_PLATFORM_NO_OS */
 193    /* must be the default driver name */
 194    if (strcmp(driverPath, DefaultDriverName) == 0)
 195       mainFunc = (_EGLMain_t) _eglMain;
 196    else
 197       error = "not builtin driver";
 198 #endif
 199
 200    if (!lib) {
 201       _eglLog(_EGL_WARNING, "Could not open driver %s (%s)",
 202               driverPath, error);
 203       if (!getenv("EGL_DRIVER"))
 204          _eglLog(_EGL_WARNING,
 205                  "The driver can be overridden by setting EGL_DRIVER");
 206       return NULL;
 207    }
 208
 209    if (!mainFunc) {
 210       _eglLog(_EGL_WARNING, "_eglMain not found in %s (%s)",
 211               driverPath, error);
 212       if (lib)
 213          close_library(lib);
 214       return NULL;
 215    }
 216
 217    *handle = lib;
 218    return mainFunc;
 219 }
 220
 221
 222 /**
 223  * Load the named driver.
 224  */
 225 static _EGLDriver *
 226 _eglLoadDriver(const char *path, const char *args)
 227 {
 228    _EGLMain_t mainFunc;
 229    lib_handle lib;
 230    _EGLDriver *drv = NULL;
 231
 232    mainFunc = _eglOpenLibrary(path, &lib);
 233    if (!mainFunc)
 234       return NULL;
 235
 236    drv = mainFunc(args);
 237    if (!drv) {
 238       if (lib)
 239          close_library(lib);
 240       return NULL;
 241    }
 242
 243    if (!drv->Name) {
 244       _eglLog(_EGL_WARNING, "Driver loaded from %s has no name", path);
 245       drv->Name = "UNNAMED";
 246    }
 247
 248    drv->Path = _eglstrdup(path);
 249    drv->Args = (args) ? _eglstrdup(args) : NULL;
 250    if (!drv->Path || (args && !drv->Args)) {
 251       if (drv->Path)
 252          free((char *) drv->Path);
 253       if (drv->Args)
 254          free((char *) drv->Args);
 255       drv->Unload(drv);
 256       if (lib)
 257          close_library(lib);
 258       return NULL;
 259    }
 260
 261    drv->LibHandle = lib;
 262
 263    return drv;
 264 }
 265
 266
 267 /**
 268  * Match a display to a preloaded driver.
 269  *
 270  * The matching is done by finding the driver with the highest score.
 271  */
 272 _EGLDriver *
 273 _eglMatchDriver(_EGLDisplay *dpy)
 274 {
 275    _EGLDriver *best_drv = NULL;
 276    EGLint best_score = -1, i;
 277
 278    for (i = 0; i < _eglGlobal.NumDrivers; i++) {
 279       _EGLDriver *drv = _eglGlobal.Drivers[i];
 280       EGLint score;
 281
 282       score = (drv->Probe) ? drv->Probe(drv, dpy) : 0;
 283       if (score > best_score) {
 284          if (best_drv) {
 285             _eglLog(_EGL_DEBUG, "driver %s has higher score than %s",
 286                   drv->Name, best_drv->Name);
 287          }
 288
 289          best_drv = drv;
 290          best_score = score;
 291          /* perfect match */
 292          if (score >= 100)
 293             break;
 294       }
 295    }
 296
 297    return best_drv;
 298 }
 299
 300
 301 /**
 302  * Preload a user driver.
 303  *
 304  * A user driver can be specified by EGL_DRIVER.
 305  */
 306 static EGLBoolean
 307 _eglPreloadUserDriver(void)
 308 {
 309 #if defined(_EGL_PLATFORM_POSIX) || defined(_EGL_PLATFORM_WINDOWS)
 310    _EGLDriver *drv;
 311    char path[1024];
 312    char *env;
 313
 314    env = getenv("EGL_DRIVER");
 315    if (!env)
 316       return EGL_FALSE;
 317
 318    if (!make_library_path(path, sizeof(path), env))
 319       return EGL_FALSE;
 320
 321    drv = _eglLoadDriver(path, NULL);
 322    if (!drv) {
 323       _eglLog(_EGL_WARNING, "EGL_DRIVER is set to an invalid driver");
 324       return EGL_FALSE;
 325    }
 326
 327    _eglGlobal.Drivers[_eglGlobal.NumDrivers++] = drv;
 328
 329    return EGL_TRUE;
 330 #else /* _EGL_PLATFORM_POSIX || _EGL_PLATFORM_WINDOWS */
 331    return EGL_FALSE;
 332 #endif
 333 }
 334
 335
 336 /**
 337  * Preload display drivers.
 338  *
 339  * Display drivers are a set of drivers that support a certain display system.
 340  * The display system may be specified by EGL_DISPLAY.
 341  *
 342  * FIXME This makes libEGL a memory hog if an user driver is not specified and
 343  * there are many display drivers.
 344  */
 345 static EGLBoolean
 346 _eglPreloadDisplayDrivers(void)
 347 {
 348 #if defined(_EGL_PLATFORM_POSIX)
 349    const char *dpy, *suffix;
 350    char path[1024], prefix[32];
 351    DIR *dirp;
 352    struct dirent *dirent;
 353
 354    dpy = getenv("EGL_DISPLAY");
 355    if (!dpy || !dpy[0])
 356       dpy = _EGL_DEFAULT_DISPLAY;
 357    if (!dpy || !dpy[0])
 358       return EGL_FALSE;
 359
 360    snprintf(prefix, sizeof(prefix), "egl_%s_", dpy);
 361    suffix = library_suffix();
 362
 363    dirp = opendir(_EGL_DRIVER_SEARCH_DIR);
 364    if (!dirp)
 365       return EGL_FALSE;
 366
 367    while ((dirent = readdir(dirp))) {
 368       _EGLDriver *drv;
 369       const char *p;
 370
 371       /* match the prefix */
 372       if (strncmp(dirent->d_name, prefix, strlen(prefix)) != 0)
 373          continue;
 374
 375       /* match the suffix */
 376       p = strrchr(dirent->d_name, '.');
 377       if ((p && !suffix) || (!p && suffix))
 378          continue;
 379       else if (p && suffix && strcmp(p + 1, suffix) != 0)
 380          continue;
 381
 382       snprintf(path, sizeof(path),
 383             _EGL_DRIVER_SEARCH_DIR"/%s", dirent->d_name);
 384
 385       drv = _eglLoadDriver(path, NULL);
 386       if (drv)
 387          _eglGlobal.Drivers[_eglGlobal.NumDrivers++] = drv;
 388    }
 389
 390    closedir(dirp);
 391
 392    return (_eglGlobal.NumDrivers > 0);
 393 #else /* _EGL_PLATFORM_POSIX */
 394    return EGL_FALSE;
 395 #endif
 396 }
 397
 398
 399 /**
 400  * Preload the default driver.
 401  */
 402 static EGLBoolean
 403 _eglPreloadDefaultDriver(void)
 404 {
 405    _EGLDriver *drv;
 406    char path[1024];
 407
 408    if (!make_library_path(path, sizeof(path), DefaultDriverName))
 409       return EGL_FALSE;
 410
 411    drv = _eglLoadDriver(path, NULL);
 412    if (!drv)
 413       return EGL_FALSE;
 414
 415    _eglGlobal.Drivers[_eglGlobal.NumDrivers++] = drv;
 416
 417    return EGL_TRUE;
 418 }
 419
 420
 421 /**
 422  * Preload drivers.
 423  *
 424  * This function loads the driver modules and creates the corresponding
 425  * _EGLDriver objects.
 426  */
 427 EGLBoolean
 428 _eglPreloadDrivers(void)
 429 {
 430    EGLBoolean loaded;
 431
 432    /* already preloaded */
 433    if (_eglGlobal.NumDrivers)
 434       return EGL_TRUE;
 435
 436    loaded = (_eglPreloadUserDriver() ||
 437              _eglPreloadDisplayDrivers() ||
 438              _eglPreloadDefaultDriver());
 439
 440    return loaded;
 441 }
 442
 443
 444 /**
 445  * Unload preloaded drivers.
 446  */
 447 void
 448 _eglUnloadDrivers(void)
 449 {
 450    EGLint i;
 451    for (i = 0; i < _eglGlobal.NumDrivers; i++) {
 452       _EGLDriver *drv = _eglGlobal.Drivers[i];
 453       lib_handle handle = drv->LibHandle;
 454
 455       if (drv->Path)
 456          free((char *) drv->Path);
 457       if (drv->Args)
 458          free((char *) drv->Args);
 459
 460       /* destroy driver */
 461       if (drv->Unload)
 462          drv->Unload(drv);
 463
 464       if (handle)
 465          close_library(handle);
 466       _eglGlobal.Drivers[i] = NULL;
 467    }
 468
 469    _eglGlobal.NumDrivers = 0;
 470 }
 471
 472
 473 /**
 474  * Plug all the available fallback routines into the given driver's
 475  * dispatch table.
 476  */
 477 void
 478 _eglInitDriverFallbacks(_EGLDriver *drv)
 479 {
 480    /* If a pointer is set to NULL, then the device driver _really_ has
 481     * to implement it.
 482     */
 483    drv->API.Initialize = NULL;
 484    drv->API.Terminate = NULL;
 485
 486    drv->API.GetConfigs = _eglGetConfigs;
 487    drv->API.ChooseConfig = _eglChooseConfig;
 488    drv->API.GetConfigAttrib = _eglGetConfigAttrib;
 489
 490    drv->API.CreateContext = _eglCreateContext;
 491    drv->API.DestroyContext = _eglDestroyContext;
 492    drv->API.MakeCurrent = _eglMakeCurrent;
 493    drv->API.QueryContext = _eglQueryContext;
 494
 495    drv->API.CreateWindowSurface = _eglCreateWindowSurface;
 496    drv->API.CreatePixmapSurface = _eglCreatePixmapSurface;
 497    drv->API.CreatePbufferSurface = _eglCreatePbufferSurface;
 498    drv->API.DestroySurface = _eglDestroySurface;
 499    drv->API.QuerySurface = _eglQuerySurface;
 500    drv->API.SurfaceAttrib = _eglSurfaceAttrib;
 501    drv->API.BindTexImage = _eglBindTexImage;
 502    drv->API.ReleaseTexImage = _eglReleaseTexImage;
 503    drv->API.SwapInterval = _eglSwapInterval;
 504    drv->API.SwapBuffers = _eglSwapBuffers;
 505    drv->API.CopyBuffers = _eglCopyBuffers;
 506
 507    drv->API.QueryString = _eglQueryString;
 508    drv->API.WaitClient = _eglWaitClient;
 509    drv->API.WaitNative = _eglWaitNative;
 510
 511 #ifdef EGL_MESA_screen_surface
 512    drv->API.ChooseModeMESA = _eglChooseModeMESA;
 513    drv->API.GetModesMESA = _eglGetModesMESA;
 514    drv->API.GetModeAttribMESA = _eglGetModeAttribMESA;
 515    drv->API.GetScreensMESA = _eglGetScreensMESA;
 516    drv->API.CreateScreenSurfaceMESA = _eglCreateScreenSurfaceMESA;
 517    drv->API.ShowScreenSurfaceMESA = _eglShowScreenSurfaceMESA;
 518    drv->API.ScreenPositionMESA = _eglScreenPositionMESA;
 519    drv->API.QueryScreenMESA = _eglQueryScreenMESA;
 520    drv->API.QueryScreenSurfaceMESA = _eglQueryScreenSurfaceMESA;
 521    drv->API.QueryScreenModeMESA = _eglQueryScreenModeMESA;
 522    drv->API.QueryModeStringMESA = _eglQueryModeStringMESA;
 523 #endif /* EGL_MESA_screen_surface */
 524
 525 #ifdef EGL_VERSION_1_2
 526    drv->API.CreatePbufferFromClientBuffer = _eglCreatePbufferFromClientBuffer;
 527 #endif /* EGL_VERSION_1_2 */
 528
 529 #ifdef EGL_KHR_image_base
 530    drv->API.CreateImageKHR = _eglCreateImageKHR;
 531    drv->API.DestroyImageKHR = _eglDestroyImageKHR;
 532 #endif /* EGL_KHR_image_base */
 533 }
 534
 535
 536 /**
 537  * Set the probe cache at the given key.
 538  *
 539  * A key, instead of a _EGLDriver, is used to allow the probe cache to be share
 540  * by multiple drivers.
 541  */
 542 void
 543 _eglSetProbeCache(EGLint key, const void *val)
 544 {
 545    EGLint idx;
 546
 547    for (idx = 0; idx < NUM_PROBE_CACHE_SLOTS; idx++) {
 548       if (!_eglProbeCache.keys[idx] || _eglProbeCache.keys[idx] == key)
 549          break;
 550    }
 551    assert(key > 0);
 552    assert(idx < NUM_PROBE_CACHE_SLOTS);
 553
 554    _eglProbeCache.keys[idx] = key;
 555    _eglProbeCache.values[idx] = val;
 556 }
 557
 558
 559 /**
 560  * Return the probe cache at the given key.
 561  */
 562 const void *
 563 _eglGetProbeCache(EGLint key)
 564 {
 565    EGLint idx;
 566
 567    for (idx = 0; idx < NUM_PROBE_CACHE_SLOTS; idx++) {
 568       if (!_eglProbeCache.keys[idx] || _eglProbeCache.keys[idx] == key)
 569          break;
 570    }
 571
 572    return (idx < NUM_PROBE_CACHE_SLOTS && _eglProbeCache.keys[idx] == key) ?
 573       _eglProbeCache.values[idx] : NULL;
 574 }