src/posix/linux_specific.c

   1 /*****************************************************************************
   2  * linux_specific.c: Linux-specific initialization
   3  *****************************************************************************
   4  * Copyright © 2008-2012 Rémi Denis-Courmont
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU Lesser General Public License as published by
   8  * the Free Software Foundation; either version 2.1 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  19  *****************************************************************************/
  20
  21 #ifdef HAVE_CONFIG_H
  22 # include "config.h"
  23 #endif
  24
  25 #include <stdio.h>
  26 #include <string.h>
  27
  28 #include <vlc_common.h>
  29 #include "libvlc.h"
  30 #include "config/configuration.h"
  31
  32 char *config_GetLibDir (void)
  33 {
  34     char *path = NULL;
  35
  36     /* Find the path to libvlc (i.e. ourselves) */
  37     FILE *maps = fopen ("/proc/self/maps", "rte");
  38     if (maps == NULL)
  39         goto error;
  40
  41     char *line = NULL;
  42     size_t linelen = 0;
  43     uintptr_t needle = (uintptr_t)config_GetLibDir;
  44
  45     for (;;)
  46     {
  47         ssize_t len = getline (&line, &linelen, maps);
  48         if (len == -1)
  49             break;
  50
  51         void *start, *end;
  52         if (sscanf (line, "%p-%p", &start, &end) < 2)
  53             continue;
  54         /* This mapping contains the address of this function. */
  55         if (needle < (uintptr_t)start || (uintptr_t)end <= needle)
  56             continue;
  57
  58         char *dir = strchr (line, '/');
  59         if (dir == NULL)
  60             continue;
  61
  62         char *file = strrchr (line, '/');
  63         if (end == NULL)
  64             continue;
  65         *file = '\0';
  66
  67         if (asprintf (&path, "%s/"PACKAGE, dir) == -1)
  68             path = NULL;
  69         break;
  70     }
  71
  72     free (line);
  73     fclose (maps);
  74 error:
  75     return (path != NULL) ? path : strdup (PKGLIBDIR);
  76 }
  77
  78 char *config_GetDataDir (void)
  79 {
  80     const char *path = getenv ("VLC_DATA_PATH");
  81     if (path != NULL)
  82         return strdup (path);
  83
  84     char *libdir = config_GetLibDir ();
  85     if (libdir == NULL)
  86         return NULL; /* OOM */
  87
  88     char *datadir = NULL;
  89
  90     /* There are no clean ways to do this, are there?
  91      * Due to multilibs, we cannot simply append ../share/. */
  92     char *p = strstr (libdir, "/lib/");
  93     if (p != NULL)
  94     {
  95         char *p2;
  96         /* Deal with nested "lib" directories. Grmbl. */
  97         while ((p2 = strstr (p + 4, "/lib/")) != NULL)
  98             p = p2;
  99         *p = '\0';
 100
 101         if (unlikely(asprintf (&datadir, "%s/share/"PACKAGE, libdir) == -1))
 102             datadir = NULL;
 103     }
 104     free (libdir);
 105     return (datadir != NULL) ? datadir : strdup (PKGDATADIR);
 106 }