git.ozlabs.org Git - petitboot/blob - devices/paths.c

   1 #define _GNU_SOURCE
   2
   3 #include <string.h>
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6
   7 #include "paths.h"
   8
   9 static char *mount_base;
  10
  11 struct device_map {
  12         char *dev, *mnt;
  13 };
  14
  15 #define DEVICE_MAP_SIZE 32
  16 static struct device_map device_map[DEVICE_MAP_SIZE];
  17
  18 const char *mountpoint_for_device(const char *dev_path)
  19 {
  20         int i;
  21         const char *basename;
  22
  23         /* shorten '/dev/foo' to 'foo' */
  24         basename = strrchr(dev_path, '/');
  25         if (basename)
  26                 basename++;
  27         else
  28                 basename = dev_path;
  29
  30         /* check existing entries in the map */
  31         for (i = 0; (i < DEVICE_MAP_SIZE) && device_map[i].dev; i++)
  32                 if (!strcmp(device_map[i].dev, basename))
  33                         return device_map[i].mnt;
  34
  35         if (i == DEVICE_MAP_SIZE)
  36                 return NULL;
  37
  38         device_map[i].dev = strdup(dev_path);
  39         asprintf(&device_map[i].mnt, "%s/%s", mount_base, basename);
  40         return device_map[i].mnt;
  41 }
  42
  43 char *resolve_path(const char *path, const char *current_mountpoint)
  44 {
  45         char *ret;
  46         const char *devpath, *sep;
  47
  48         sep = strchr(path, ':');
  49         if (!sep) {
  50                 devpath = current_mountpoint;
  51                 asprintf(&ret, "%s/%s", devpath, path);
  52         } else {
  53                 /* copy just the device name into tmp */
  54                 char *dev = strndup(path, sep - path);
  55                 devpath = mountpoint_for_device(dev);
  56                 asprintf(&ret, "%s/%s", devpath, sep + 1);
  57                 free(dev);
  58         }
  59
  60         return ret;
  61 }
  62
  63 void set_mount_base(const char *path)
  64 {
  65         if (mount_base)
  66                 free(mount_base);
  67         mount_base = strdup(path);
  68 }
  69