gbm/dri: Expose visuals table through gbm_dri_device
[mesa.git] / src / gbm / main / backend.c
1 /*
2 * Copyright © 2011 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
19 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
20 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22 * DEALINGS IN THE SOFTWARE.
23 *
24 * Authors:
25 * Benjamin Franzke <benjaminfranzke@googlemail.com>
26 */
27
28 #include <stdio.h>
29 #include <stddef.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <limits.h>
33
34 #include "backend.h"
35
36 #define ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0]))
37
38 extern const struct gbm_backend gbm_dri_backend;
39
40 struct backend_desc {
41 const char *name;
42 const struct gbm_backend *builtin;
43 };
44
45 static const struct backend_desc backends[] = {
46 { "gbm_dri.so", &gbm_dri_backend },
47 };
48
49 static const void *
50 load_backend(const struct backend_desc *backend)
51 {
52 const void *init = NULL;
53
54 if (backend == NULL)
55 return NULL;
56
57 if (backend->builtin) {
58 init = backend->builtin;
59 }
60
61 return init;
62 }
63
64 static const struct backend_desc *
65 find_backend(const char *name)
66 {
67 const struct backend_desc *backend = NULL;
68 unsigned i;
69
70 for (i = 0; i < ARRAY_SIZE(backends); ++i) {
71 if (strcmp(backends[i].name, name) == 0) {
72 backend = &backends[i];
73 break;
74 }
75 }
76
77 return backend;
78 }
79
80 struct gbm_device *
81 _gbm_create_device(int fd)
82 {
83 const struct gbm_backend *backend = NULL;
84 struct gbm_device *dev = NULL;
85 unsigned i;
86 const char *b;
87
88 b = getenv("GBM_BACKEND");
89 if (b)
90 backend = load_backend(find_backend(b));
91
92 if (backend)
93 dev = backend->create_device(fd);
94
95 for (i = 0; i < ARRAY_SIZE(backends) && dev == NULL; ++i) {
96 backend = load_backend(&backends[i]);
97 if (backend == NULL)
98 continue;
99
100 dev = backend->create_device(fd);
101 }
102
103 return dev;
104 }