/**************************************************************************
*
* Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
* Copyright 2009-2010 Chia-I Wu <olvaffe@gmail.com>
* Copyright 2010-2011 LunarG, Inc.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
/**
* Functions for choosing and opening/loading device drivers.
*/
#include <assert.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include "eglstring.h"
#include "egldefines.h"
#include "egldisplay.h"
#include "egldriver.h"
#include "egllog.h"
#include "eglmutex.h"
typedef unsigned int lib_handle;
lib_handle load_library(const char *name);
void *get_proc_address(lib_handle lib, char *proc_name);
typedef struct _egl_module {
char *Path;
_EGLMain_t BuiltIn;
void *Handle;
_EGLDriver *Driver;
} _EGLModule;
static _EGL_DECLARE_MUTEX(_eglModuleMutex);
static _EGLArray *_eglModules;
const struct {
const char *name;
_EGLMain_t main;
} _eglBuiltInDrivers[] = {
#ifdef _EGL_BUILT_IN_DRIVER_GALLIUM
{ "egl_gallium", _eglBuiltInDriverGALLIUM },
#endif
#ifdef _EGL_BUILT_IN_DRIVER_DRI2
{ "egl_dri2", _eglBuiltInDriverDRI2 },
#endif
#ifdef _EGL_BUILT_IN_DRIVER_GLX
{ "egl_glx", _eglBuiltInDriverGLX },
#endif
{ NULL, NULL }
};
/**
* Wrappers for dlopen/dlclose()
*/
#if defined(_EGL_OS_WINDOWS)
typedef HMODULE lib_handle;
static HMODULE
open_library(const char *filename)
{
return LoadLibrary(filename);
}
static void
close_library(HMODULE lib)
{
FreeLibrary(lib);
}
static const char *
library_suffix(void)
{
return ".dll";
}
#elif defined(_EGL_OS_UNIX)
typedef void * lib_handle;
static void *
open_library(const char *filename)
{
return dlopen(filename, RTLD_LAZY);
}
static void
close_library(void *lib)
{
dlclose(lib);
}
static const char *
library_suffix(void)
{
return ".so";
}
#endif
/**
* Open the named driver and find its bootstrap function: _eglMain().
*/
static _EGLMain_t
_eglOpenLibrary(const char *driverPath, lib_handle *handle)
{
lib_handle lib;
_EGLMain_t mainFunc = NULL;
const char *error = "unknown error";
assert(driverPath);
_eglLog(_EGL_DEBUG, "dlopen(%s)", driverPath);
lib = load_library(driverPath);
if (!lib) {
_eglLog(_EGL_WARNING, "Could not open driver %s (%s)",
driverPath, error);
return NULL;
}
mainFunc = (_EGLMain_t) get_proc_address(lib, "_eglMain");
if (!mainFunc) {
_eglLog(_EGL_WARNING, "_eglMain not found in %s (%s)",
driverPath, error);
return NULL;
}
*handle = lib;
return mainFunc;
}
/**
* Load a module and create the driver object.
*/
static EGLBoolean
_eglLoadModule(_EGLModule *mod)
{
_EGLMain_t mainFunc;
lib_handle lib;
_EGLDriver *drv;
if (mod->Driver)
return EGL_TRUE;
if (mod->BuiltIn) {
lib = (lib_handle) NULL;
mainFunc = mod->BuiltIn;
}
else {
mainFunc = _eglOpenLibrary(mod->Path, &lib);
if (!mainFunc)
return EGL_FALSE;
}
drv = mainFunc(NULL);
if (!drv) {
return EGL_FALSE;
}
if (!drv->Name) {
_eglLog(_EGL_WARNING, "Driver loaded from %s has no name", mod->Path);
drv->Name = "UNNAMED";
}
mod->Handle = (void *) lib;
mod->Driver = drv;
return EGL_TRUE;
}
/**
* Unload a module.
*/
static void
_eglUnloadModule(_EGLModule *mod)
{
#if defined(_EGL_OS_UNIX)
/* destroy the driver */
if (mod->Driver && mod->Driver->Unload)
mod->Driver->Unload(mod->Driver);
/*
* XXX At this point (atexit), the module might be the last reference to
* libEGL. Closing the module might unmap libEGL and give problems.
*/
#if 0
if (mod->Handle)
close_library(mod->Handle);
#endif
#elif defined(_EGL_OS_WINDOWS)
/* XXX Windows unloads DLLs before atexit */
#endif
mod->Driver = NULL;
mod->Handle = NULL;
}
/**
* Add a module to the module array.
*/
static _EGLModule *
_eglAddModule(const char *path)
{
_EGLModule *mod;
EGLint i;
if (!_eglModules) {
_eglModules = _eglCreateArray("Module", 8);
if (!_eglModules)
return NULL;
}
/* find duplicates */
for (i = 0; i < _eglModules->Size; i++) {
mod = _eglModules->Elements[i];
if (strcmp(mod->Path, path) == 0)
return mod;
}
/* allocate a new one */
mod = calloc(1, sizeof(*mod));
if (mod) {
mod->Path = _eglstrdup(path);
if (!mod->Path) {
free(mod);
mod = NULL;
}
}
if (mod) {
_eglAppendArray(_eglModules, (void *) mod);
_eglLog(_EGL_DEBUG, "added %s to module array", mod->Path);
}
return mod;
}
/**
* Free a module.
*/
static void
_eglFreeModule(void *module)
{
_EGLModule *mod = (_EGLModule *) module;
_eglUnloadModule(mod);
free(mod->Path);
free(mod);
}
#if 0
/**
* A loader function for use with _eglPreloadForEach. The loader data is the
* filename of the driver. This function stops on the first valid driver.
*/
static EGLBoolean
_eglLoaderFile(const char *dir, size_t len, void *loader_data)
{
char path[1024];
const char *filename = (const char *) loader_data;
size_t flen = strlen(filename);
/* make a full path */
if (len + flen + 2 > sizeof(path))
return EGL_TRUE;
if (len) {
memcpy(path, dir, len);
path[len++] = '/';
}
memcpy(path + len, filename, flen);
len += flen;
path[len] = '\0';
if (library_suffix()) {
const char *suffix = library_suffix();
size_t slen = strlen(suffix);
const char *p;
EGLBoolean need_suffix;
p = filename + flen - slen;
need_suffix = (p < filename || strcmp(p, suffix) != 0);
if (need_suffix) {
/* overflow */
if (len + slen + 1 > sizeof(path))
return EGL_TRUE;
strcpy(path + len, suffix);
}
}
#if defined(_EGL_OS_UNIX)
/* check if the file exists */
if (access(path, F_OK))
return EGL_TRUE;
#endif
_eglAddModule(path);
return EGL_TRUE;
}
/**
* Run the callback function on each driver directory.
*
* The process may end prematurely if the callback function returns false.
*/
static void
_eglPreloadForEach(const char *search_path,
EGLBoolean (*loader)(const char *, size_t, void *),
void *loader_data)
{
const char *cur, *next;
size_t len;
cur = search_path;
while (cur) {
next = strchr(cur, ':');
len = (next) ? next - cur : strlen(cur);
if (!loader(cur, len, loader_data))
break;
cur = (next) ? next + 1 : NULL;
}
}
/**
* Return a list of colon-separated driver directories.
*/
static const char *
_eglGetSearchPath(void)
{
static char search_path[1024];
#if defined(_EGL_OS_UNIX) || defined(_EGL_OS_WINDOWS)
if (search_path[0] == '\0') {
char *buf = search_path;
size_t len = sizeof(search_path);
EGLBoolean use_env;
char dir_sep;
int ret;
#if defined(_EGL_OS_UNIX)
use_env = (geteuid() == getuid() && getegid() == getgid());
dir_sep = '/';
#else
use_env = EGL_TRUE;
dir_sep = '\\';
#endif
if (use_env) {
char *p;
/* extract the dirname from EGL_DRIVER */
p = getenv("EGL_DRIVER");
if (p && strchr(p, dir_sep)) {
ret = _eglsnprintf(buf, len, "%s", p);
if (ret > 0 && ret < len) {
p = strrchr(buf, dir_sep);
*p++ = ':';
len -= p - buf;
buf = p;
}
}
/* append EGL_DRIVERS_PATH */
p = getenv("EGL_DRIVERS_PATH");
if (p) {
ret = _eglsnprintf(buf, len, "%s:", p);
if (ret > 0 && ret < len) {
buf += ret;
len -= ret;
}
}
}
else {
_eglLog(_EGL_DEBUG,
"ignore EGL_DRIVERS_PATH for setuid/setgid binaries");
}
ret = _eglsnprintf(buf, len, "%s", _EGL_DRIVER_SEARCH_DIR);
if (ret < 0 || ret >= len)
search_path[0] = '\0';
_eglLog(_EGL_DEBUG, "EGL search path is %s", search_path);
}
#endif /* defined(_EGL_OS_UNIX) || defined(_EGL_OS_WINDOWS) */
return search_path;
}
/**
* Add the user driver to the module array.
*
* The user driver is specified by EGL_DRIVER.
*/
static EGLBoolean
_eglAddUserDriver(void)
{
const char *search_path = _eglGetSearchPath();
char *env;
size_t name_len = 0;
env = getenv("EGL_DRIVER");
#if defined(_EGL_OS_UNIX)
if (env && strchr(env, '/')) {
search_path = "";
if ((geteuid() != getuid() || getegid() != getgid())) {
_eglLog(_EGL_DEBUG,
"ignore EGL_DRIVER for setuid/setgid binaries");
env = NULL;
}
}
else if (env) {
char *suffix = strchr(env, '.');
name_len = (suffix) ? suffix - env : strlen(env);
}
#else
if (env)
name_len = strlen(env);
#endif /* _EGL_OS_UNIX */
/*
* Try built-in drivers first if we know the driver name. This makes sure
* we do not load the outdated external driver that is still on the
* filesystem.
*/
if (name_len) {
_EGLModule *mod;
EGLint i;
for (i = 0; _eglBuiltInDrivers[i].name; i++) {
if (strlen(_eglBuiltInDrivers[i].name) == name_len &&
!strncmp(_eglBuiltInDrivers[i].name, env, name_len)) {
mod = _eglAddModule(env);
if (mod)
mod->BuiltIn = _eglBuiltInDrivers[i].main;
return EGL_TRUE;
}
}
}
/* otherwise, treat env as a path */
if (env) {
_eglPreloadForEach(search_path, _eglLoaderFile, (void *) env);
return EGL_TRUE;
}
return EGL_FALSE;
}
/**
* Add egl_gallium to the module array.
*/
static void
_eglAddGalliumDriver(void)
{
#ifndef _EGL_BUILT_IN_DRIVER_GALLIUM
void *external = (void *) "egl_gallium";
_eglPreloadForEach(_eglGetSearchPath(), _eglLoaderFile, external);
#endif
}
#endif
/**
* Add built-in drivers to the module array.
*/
static void
_eglAddBuiltInDrivers(void)
{
_EGLModule *mod;
EGLint i;
for (i = 0; _eglBuiltInDrivers[i].name; i++) {
mod = _eglAddModule(_eglBuiltInDrivers[i].name);
if (mod)
mod->BuiltIn = _eglBuiltInDrivers[i].main;
}
}
/**
* Add drivers to the module array. Drivers will be loaded as they are matched
* to displays.
*/
static EGLBoolean
_eglAddDrivers(void)
{
if (_eglModules)
return EGL_TRUE;
// if (!_eglAddUserDriver()) {
/*
* Add other drivers only when EGL_DRIVER is not set. The order here
* decides the priorities.
*/
// _eglAddGalliumDriver();
_eglAddBuiltInDrivers();
// }
return (_eglModules != NULL);
}
/**
* A helper function for _eglMatchDriver. It finds the first driver that can
* initialize the display and return.
*/
static _EGLDriver *
_eglMatchAndInitialize(_EGLDisplay *dpy)
{
_EGLDriver *drv = NULL;
EGLint i = 0;
if (!_eglAddDrivers()) {
_eglLog(_EGL_WARNING, "failed to find any driver");
return NULL;
}
if (dpy->Driver) {
drv = dpy->Driver;
/* no re-matching? */
if (!drv->API.Initialize(drv, dpy))
drv = NULL;
return drv;
}
while (i < _eglModules->Size) {
_EGLModule *mod = (_EGLModule *) _eglModules->Elements[i];
if (!_eglLoadModule(mod)) {
/* remove invalid modules */
_eglEraseArray(_eglModules, i, _eglFreeModule);
continue;
}
if (mod->Driver->API.Initialize(mod->Driver, dpy)) {
drv = mod->Driver;
break;
}
else {
i++;
}
}
return drv;
}
/**
* Match a display to a driver. The display is initialized unless test_only is
* true. The matching is done by finding the first driver that can initialize
* the display.
*/
_EGLDriver *
_eglMatchDriver(_EGLDisplay *dpy, EGLBoolean test_only)
{
_EGLDriver *best_drv;
assert(!dpy->Initialized);
_eglLockMutex(&_eglModuleMutex);
/* set options */
dpy->Options.TestOnly = test_only;
dpy->Options.UseFallback = EGL_FALSE;
best_drv = _eglMatchAndInitialize(dpy);
if (!best_drv) {
dpy->Options.UseFallback = EGL_TRUE;
best_drv = _eglMatchAndInitialize(dpy);
}
_eglUnlockMutex(&_eglModuleMutex);
if (best_drv) {
_eglLog(_EGL_DEBUG, "the best driver is %s%s",
best_drv->Name, (test_only) ? " (test only) " : "");
if (!test_only) {
dpy->Driver = best_drv;
dpy->Initialized = EGL_TRUE;
}
}
return best_drv;
}
__eglMustCastToProperFunctionPointerType
_eglGetDriverProc(const char *procname)
{
EGLint i;
_EGLProc proc = NULL;
if (!_eglModules) {
/* load the driver for the default display */
EGLDisplay egldpy = eglGetDisplay(EGL_DEFAULT_DISPLAY);
_EGLDisplay *dpy = _eglLookupDisplay(egldpy);
if (!dpy || !_eglMatchDriver(dpy, EGL_TRUE))
return NULL;
}
for (i = 0; i < _eglModules->Size; i++) {
_EGLModule *mod = (_EGLModule *) _eglModules->Elements[i];
if (!mod->Driver)
break;
proc = mod->Driver->API.GetProcAddress(mod->Driver, procname);
if (proc)
break;
}
return proc;
}
/**
* Unload all drivers.
*/
void
_eglUnloadDrivers(void)
{
/* this is called at atexit time */
if (_eglModules) {
_eglDestroyArray(_eglModules, _eglFreeModule);
_eglModules = NULL;
}
}
#if 0
/**
* Invoke a callback function on each EGL search path.
*
* The first argument of the callback function is the name of the search path.
* The second argument is the length of the name.
*/
void
_eglSearchPathForEach(EGLBoolean (*callback)(const char *, size_t, void *),
void *callback_data)
{
const char *search_path = _eglGetSearchPath();
_eglPreloadForEach(search_path, callback, callback_data);
}
#endif