1 /**************************************************************************
3 * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
4 * Copyright 2009-2010 Chia-I Wu <olvaffe@gmail.com>
5 * Copyright 2010-2011 LunarG, Inc.
8 * Permission is hereby granted, free of charge, to any person obtaining a
9 * copy of this software and associated documentation files (the
10 * "Software"), to deal in the Software without restriction, including
11 * without limitation the rights to use, copy, modify, merge, publish,
12 * distribute, sub license, and/or sell copies of the Software, and to
13 * permit persons to whom the Software is furnished to do so, subject to
14 * the following conditions:
16 * The above copyright notice and this permission notice (including the
17 * next paragraph) shall be included in all copies or substantial portions
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
25 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
26 * DEALINGS IN THE SOFTWARE.
28 **************************************************************************/
32 * Functions for choosing and opening/loading device drivers.
41 #include "eglstring.h"
42 #include "egldefines.h"
43 #include "egldisplay.h"
44 #include "egldriver.h"
48 #if defined(_EGL_OS_UNIX)
50 #include <sys/types.h>
56 typedef struct _egl_module
{
63 static _EGLMutex _eglModuleMutex
= _EGL_MUTEX_INITIALIZER
;
64 static _EGLArray
*_eglModules
;
69 } _eglBuiltInDrivers
[] = {
70 #ifdef _EGL_BUILT_IN_DRIVER_GALLIUM
71 { "egl_gallium", _eglBuiltInDriverGALLIUM
},
73 #ifdef _EGL_BUILT_IN_DRIVER_DRI2
74 { "egl_dri2", _eglBuiltInDriverDRI2
},
76 #ifdef _EGL_BUILT_IN_DRIVER_GLX
77 { "egl_glx", _eglBuiltInDriverGLX
},
83 * Wrappers for dlopen/dlclose()
85 #if defined(_EGL_OS_WINDOWS)
88 typedef HMODULE lib_handle
;
91 open_library(const char *filename
)
93 return LoadLibrary(filename
);
97 close_library(HMODULE lib
)
110 #elif defined(_EGL_OS_UNIX)
113 typedef void * lib_handle
;
116 open_library(const char *filename
)
118 return dlopen(filename
, RTLD_LAZY
);
122 close_library(void *lib
)
139 * Open the named driver and find its bootstrap function: _eglMain().
142 _eglOpenLibrary(const char *driverPath
, lib_handle
*handle
)
145 _EGLMain_t mainFunc
= NULL
;
146 const char *error
= "unknown error";
150 _eglLog(_EGL_DEBUG
, "dlopen(%s)", driverPath
);
151 lib
= open_library(driverPath
);
153 #if defined(_EGL_OS_WINDOWS)
156 mainFunc
= (_EGLMain_t
) GetProcAddress(lib
, "_eglMain");
157 #elif defined(_EGL_OS_UNIX)
163 /* direct cast gives a warning when compiled with -pedantic */
164 tmp
.ptr
= dlsym(lib
, "_eglMain");
175 _eglLog(_EGL_WARNING
, "Could not open driver %s (%s)",
181 _eglLog(_EGL_WARNING
, "_eglMain not found in %s (%s)",
194 * Load a module and create the driver object.
197 _eglLoadModule(_EGLModule
*mod
)
207 lib
= (lib_handle
) NULL
;
208 mainFunc
= mod
->BuiltIn
;
211 mainFunc
= _eglOpenLibrary(mod
->Path
, &lib
);
216 drv
= mainFunc(NULL
);
224 _eglLog(_EGL_WARNING
, "Driver loaded from %s has no name", mod
->Path
);
225 drv
->Name
= "UNNAMED";
228 mod
->Handle
= (void *) lib
;
239 _eglUnloadModule(_EGLModule
*mod
)
241 #if defined(_EGL_OS_UNIX)
242 /* destroy the driver */
243 if (mod
->Driver
&& mod
->Driver
->Unload
)
244 mod
->Driver
->Unload(mod
->Driver
);
247 * XXX At this point (atexit), the module might be the last reference to
248 * libEGL. Closing the module might unmap libEGL and give problems.
252 close_library(mod
->Handle
);
254 #elif defined(_EGL_OS_WINDOWS)
255 /* XXX Windows unloads DLLs before atexit */
264 * Add a module to the module array.
267 _eglAddModule(const char *path
)
273 _eglModules
= _eglCreateArray("Module", 8);
278 /* find duplicates */
279 for (i
= 0; i
< _eglModules
->Size
; i
++) {
280 mod
= _eglModules
->Elements
[i
];
281 if (strcmp(mod
->Path
, path
) == 0)
285 /* allocate a new one */
286 mod
= calloc(1, sizeof(*mod
));
288 mod
->Path
= _eglstrdup(path
);
295 _eglAppendArray(_eglModules
, (void *) mod
);
296 _eglLog(_EGL_DEBUG
, "added %s to module array", mod
->Path
);
307 _eglFreeModule(void *module
)
309 _EGLModule
*mod
= (_EGLModule
*) module
;
311 _eglUnloadModule(mod
);
318 * A loader function for use with _eglPreloadForEach. The loader data is the
319 * filename of the driver. This function stops on the first valid driver.
322 _eglLoaderFile(const char *dir
, size_t len
, void *loader_data
)
325 const char *filename
= (const char *) loader_data
;
326 size_t flen
= strlen(filename
);
328 /* make a full path */
329 if (len
+ flen
+ 2 > sizeof(path
))
332 memcpy(path
, dir
, len
);
335 memcpy(path
+ len
, filename
, flen
);
339 if (library_suffix()) {
340 const char *suffix
= library_suffix();
341 size_t slen
= strlen(suffix
);
343 EGLBoolean need_suffix
;
345 p
= filename
+ flen
- slen
;
346 need_suffix
= (p
< filename
|| strcmp(p
, suffix
) != 0);
349 if (len
+ slen
+ 1 > sizeof(path
))
351 strcpy(path
+ len
, suffix
);
355 #if defined(_EGL_OS_UNIX)
356 /* check if the file exists */
357 if (access(path
, F_OK
))
368 * Run the callback function on each driver directory.
370 * The process may end prematurely if the callback function returns false.
373 _eglPreloadForEach(const char *search_path
,
374 EGLBoolean (*loader
)(const char *, size_t, void *),
377 const char *cur
, *next
;
382 next
= strchr(cur
, ':');
383 len
= (next
) ? next
- cur
: strlen(cur
);
385 if (!loader(cur
, len
, loader_data
))
388 cur
= (next
) ? next
+ 1 : NULL
;
394 * Return a list of colon-separated driver directories.
397 _eglGetSearchPath(void)
399 static char search_path
[1024];
401 #if defined(_EGL_OS_UNIX) || defined(_EGL_OS_WINDOWS)
402 if (search_path
[0] == '\0') {
403 char *buf
= search_path
;
404 size_t len
= sizeof(search_path
);
409 #if defined(_EGL_OS_UNIX)
410 use_env
= (geteuid() == getuid() && getegid() == getgid());
420 /* extract the dirname from EGL_DRIVER */
421 p
= getenv("EGL_DRIVER");
422 if (p
&& strchr(p
, dir_sep
)) {
423 ret
= _eglsnprintf(buf
, len
, "%s", p
);
424 if (ret
> 0 && ret
< len
) {
425 p
= strrchr(buf
, dir_sep
);
433 /* append EGL_DRIVERS_PATH */
434 p
= getenv("EGL_DRIVERS_PATH");
436 ret
= _eglsnprintf(buf
, len
, "%s:", p
);
437 if (ret
> 0 && ret
< len
) {
445 "ignore EGL_DRIVERS_PATH for setuid/setgid binaries");
448 ret
= _eglsnprintf(buf
, len
, "%s", _EGL_DRIVER_SEARCH_DIR
);
449 if (ret
< 0 || ret
>= len
)
450 search_path
[0] = '\0';
452 _eglLog(_EGL_DEBUG
, "EGL search path is %s", search_path
);
454 #endif /* defined(_EGL_OS_UNIX) || defined(_EGL_OS_WINDOWS) */
461 * Add the user driver to the module array.
463 * The user driver is specified by EGL_DRIVER.
466 _eglAddUserDriver(void)
468 const char *search_path
= _eglGetSearchPath();
472 env
= getenv("EGL_DRIVER");
473 #if defined(_EGL_OS_UNIX)
474 if (env
&& strchr(env
, '/')) {
476 if ((geteuid() != getuid() || getegid() != getgid())) {
478 "ignore EGL_DRIVER for setuid/setgid binaries");
483 char *suffix
= strchr(env
, '.');
484 name_len
= (suffix
) ? suffix
- env
: strlen(env
);
488 name_len
= strlen(env
);
489 #endif /* _EGL_OS_UNIX */
492 * Try built-in drivers first if we know the driver name. This makes sure
493 * we do not load the outdated external driver that is still on the
500 for (i
= 0; _eglBuiltInDrivers
[i
].name
; i
++) {
501 if (strlen(_eglBuiltInDrivers
[i
].name
) == name_len
&&
502 !strncmp(_eglBuiltInDrivers
[i
].name
, env
, name_len
)) {
503 mod
= _eglAddModule(env
);
505 mod
->BuiltIn
= _eglBuiltInDrivers
[i
].main
;
512 /* otherwise, treat env as a path */
514 _eglPreloadForEach(search_path
, _eglLoaderFile
, (void *) env
);
524 * Add egl_gallium to the module array.
527 _eglAddGalliumDriver(void)
529 #ifndef _EGL_BUILT_IN_DRIVER_GALLIUM
530 void *external
= (void *) "egl_gallium";
531 _eglPreloadForEach(_eglGetSearchPath(), _eglLoaderFile
, external
);
537 * Add built-in drivers to the module array.
540 _eglAddBuiltInDrivers(void)
545 for (i
= 0; _eglBuiltInDrivers
[i
].name
; i
++) {
546 mod
= _eglAddModule(_eglBuiltInDrivers
[i
].name
);
548 mod
->BuiltIn
= _eglBuiltInDrivers
[i
].main
;
554 * Add drivers to the module array. Drivers will be loaded as they are matched
563 if (!_eglAddUserDriver()) {
565 * Add other drivers only when EGL_DRIVER is not set. The order here
566 * decides the priorities.
568 _eglAddGalliumDriver();
569 _eglAddBuiltInDrivers();
572 return (_eglModules
!= NULL
);
577 * A helper function for _eglMatchDriver. It finds the first driver that can
578 * initialize the display and return.
581 _eglMatchAndInitialize(_EGLDisplay
*dpy
)
583 _EGLDriver
*drv
= NULL
;
586 if (!_eglAddDrivers()) {
587 _eglLog(_EGL_WARNING
, "failed to find any driver");
593 /* no re-matching? */
594 if (!drv
->API
.Initialize(drv
, dpy
))
599 while (i
< _eglModules
->Size
) {
600 _EGLModule
*mod
= (_EGLModule
*) _eglModules
->Elements
[i
];
602 if (!_eglLoadModule(mod
)) {
603 /* remove invalid modules */
604 _eglEraseArray(_eglModules
, i
, _eglFreeModule
);
608 if (mod
->Driver
->API
.Initialize(mod
->Driver
, dpy
)) {
622 * Match a display to a driver. The display is initialized unless test_only is
623 * true. The matching is done by finding the first driver that can initialize
627 _eglMatchDriver(_EGLDisplay
*dpy
, EGLBoolean test_only
)
629 _EGLDriver
*best_drv
;
631 assert(!dpy
->Initialized
);
633 _eglLockMutex(&_eglModuleMutex
);
636 dpy
->Options
.TestOnly
= test_only
;
637 dpy
->Options
.UseFallback
= EGL_FALSE
;
639 best_drv
= _eglMatchAndInitialize(dpy
);
641 dpy
->Options
.UseFallback
= EGL_TRUE
;
642 best_drv
= _eglMatchAndInitialize(dpy
);
645 _eglUnlockMutex(&_eglModuleMutex
);
648 _eglLog(_EGL_DEBUG
, "the best driver is %s%s",
649 best_drv
->Name
, (test_only
) ? " (test only) " : "");
651 dpy
->Driver
= best_drv
;
652 dpy
->Initialized
= EGL_TRUE
;
660 __eglMustCastToProperFunctionPointerType
661 _eglGetDriverProc(const char *procname
)
664 _EGLProc proc
= NULL
;
667 /* load the driver for the default display */
668 EGLDisplay egldpy
= eglGetDisplay(EGL_DEFAULT_DISPLAY
);
669 _EGLDisplay
*dpy
= _eglLookupDisplay(egldpy
);
670 if (!dpy
|| !_eglMatchDriver(dpy
, EGL_TRUE
))
674 for (i
= 0; i
< _eglModules
->Size
; i
++) {
675 _EGLModule
*mod
= (_EGLModule
*) _eglModules
->Elements
[i
];
679 proc
= mod
->Driver
->API
.GetProcAddress(mod
->Driver
, procname
);
689 * Unload all drivers.
692 _eglUnloadDrivers(void)
694 /* this is called at atexit time */
696 _eglDestroyArray(_eglModules
, _eglFreeModule
);
703 * Invoke a callback function on each EGL search path.
705 * The first argument of the callback function is the name of the search path.
706 * The second argument is the length of the name.
709 _eglSearchPathForEach(EGLBoolean (*callback
)(const char *, size_t, void *),
712 const char *search_path
= _eglGetSearchPath();
713 _eglPreloadForEach(search_path
, callback
, callback_data
);