util/drm.c

   1 /*
   2  * Copyright (C) 2015-2016 Gerd Hoffmann <kraxel@redhat.com>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17 #include "qemu/osdep.h"
  18 #include "qemu/drm.h"
  19
  20 #include <glob.h>
  21 #include <dirent.h>
  22
  23 int qemu_drm_rendernode_open(const char *rendernode)
  24 {
  25     DIR *dir;
  26     struct dirent *e;
  27     int r, fd;
  28     char *p;
  29
  30     if (rendernode) {
  31         return open(rendernode, O_RDWR | O_CLOEXEC | O_NOCTTY | O_NONBLOCK);
  32     }
  33
  34     dir = opendir("/dev/dri");
  35     if (!dir) {
  36         return -1;
  37     }
  38
  39     fd = -1;
  40     while ((e = readdir(dir))) {
  41         if (e->d_type != DT_CHR) {
  42             continue;
  43         }
  44
  45         if (strncmp(e->d_name, "renderD", 7)) {
  46             continue;
  47         }
  48
  49         p = g_strdup_printf("/dev/dri/%s", e->d_name);
  50
  51         r = open(p, O_RDWR | O_CLOEXEC | O_NOCTTY | O_NONBLOCK);
  52         if (r < 0) {
  53             g_free(p);
  54             continue;
  55         }
  56         fd = r;
  57         g_free(p);
  58         break;
  59     }
  60
  61     closedir(dir);
  62     if (fd < 0) {
  63         return -1;
  64     }
  65     return fd;
  66 }