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/*
* Copyright © 2011 Intel Corporation
*
* 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, sublicense,
* 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.
*
* Authors:
* Benjamin Franzke <benjaminfranzke@googlemail.com>
*/
#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <dlfcn.h>
#include "backend.h"
#define ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0]))
extern const struct gbm_backend gbm_dri_backend;
struct backend_desc {
const char *name;
const struct gbm_backend *builtin;
};
static const struct backend_desc backends[] = {
{ "gbm_dri.so", &gbm_dri_backend },
{ "gbm_gallium_drm.so", NULL },
};
static const void *
load_backend(const struct backend_desc *backend)
{
char path[PATH_MAX];
const void *init = NULL;
void *module;
const char *name;
const char *entrypoint = "gbm_backend";
if (backend == NULL)
return NULL;
name = backend->name;
if (backend->builtin) {
init = backend->builtin;
} else {
if (name[0] != '/')
snprintf(path, sizeof path, MODULEDIR "/%s", name);
else
snprintf(path, sizeof path, "%s", name);
module = dlopen(path, RTLD_NOW | RTLD_GLOBAL);
if (!module) {
fprintf(stderr,
"failed to load module: %s\n", dlerror());
return NULL;
}
init = dlsym(module, entrypoint);
if (!init)
return NULL;
}
return init;
}
static const struct backend_desc *
find_backend(const char *name)
{
const struct backend_desc *backend = NULL;
int i;
for (i = 0; i < ARRAY_SIZE(backends); ++i) {
if (strcmp(backends[i].name, name) == 0) {
backend = &backends[i];
break;
}
}
return backend;
}
struct gbm_device *
_gbm_create_device(int fd)
{
const struct gbm_backend *backend = NULL;
struct gbm_device *dev = NULL;
int i;
const char *b;
b = getenv("GBM_BACKEND");
if (b)
backend = load_backend(find_backend(b));
if (backend)
dev = backend->create_device(fd);
for (i = 0; i < ARRAY_SIZE(backends) && dev == NULL; ++i) {
backend = load_backend(&backends[i]);
if (backend == NULL)
continue;
dev = backend->create_device(fd);
}
return dev;
}
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