src/udev/udev-builtin-hwdb.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2012 Kay Sievers <kay@vrfy.org>
   5
   6   systemd 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   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   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 systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <stdio.h>
  21 #include <errno.h>
  22 #include <string.h>
  23 #include <inttypes.h>
  24 #include <ctype.h>
  25 #include <stdlib.h>
  26 #include <fnmatch.h>
  27 #include <getopt.h>
  28
  29 #include "udev.h"
  30
  31 static struct udev_hwdb *hwdb;
  32
  33 int udev_builtin_hwdb_lookup(struct udev_device *dev,
  34                              const char *modalias, const char *filter, bool test) {
  35         struct udev_list_entry *entry;
  36         int n = 0;
  37
  38         if (!hwdb)
  39                 return -ENOENT;
  40
  41         udev_list_entry_foreach(entry, udev_hwdb_get_properties_list_entry(hwdb, modalias, 0)) {
  42                 if (filter && fnmatch(filter, udev_list_entry_get_name(entry), FNM_NOESCAPE) != 0)
  43                         continue;
  44
  45                 if (udev_builtin_add_property(dev, test,
  46                                               udev_list_entry_get_name(entry),
  47                                               udev_list_entry_get_value(entry)) < 0)
  48                         return -ENOMEM;
  49                 n++;
  50         }
  51         return n;
  52 }
  53
  54 static const char *modalias_usb(struct udev_device *dev, char *s, size_t size) {
  55         const char *v, *p;
  56         int vn, pn;
  57
  58         v = udev_device_get_sysattr_value(dev, "idVendor");
  59         if (!v)
  60                 return NULL;
  61         p = udev_device_get_sysattr_value(dev, "idProduct");
  62         if (!p)
  63                 return NULL;
  64         vn = strtol(v, NULL, 16);
  65         if (vn <= 0)
  66                 return NULL;
  67         pn = strtol(p, NULL, 16);
  68         if (pn <= 0)
  69                 return NULL;
  70         snprintf(s, size, "usb:v%04Xp%04X*", vn, pn);
  71         return s;
  72 }
  73
  74 static int udev_builtin_hwdb_search(struct udev_device *dev, struct udev_device *srcdev,
  75                                     const char *subsystem, const char *filter, bool test) {
  76         struct udev_device *d;
  77         char s[16];
  78         int n = 0;
  79
  80         for (d = srcdev; d; d = udev_device_get_parent(d)) {
  81                 const char *dsubsys;
  82                 const char *modalias = NULL;
  83
  84                 dsubsys = udev_device_get_subsystem(d);
  85                 if (!dsubsys)
  86                         continue;
  87
  88                 /* look only at devices of a specific subsystem */
  89                 if (subsystem && !streq(dsubsys, subsystem))
  90                         continue;
  91
  92                 /* the usb_device does not have a modalias, compose one */
  93                 if (streq(dsubsys, "usb"))
  94                         modalias = modalias_usb(d, s, sizeof(s));
  95
  96                 if (!modalias)
  97                         modalias = udev_device_get_property_value(d, "MODALIAS");
  98
  99                 if (!modalias)
 100                         continue;
 101
 102                 n = udev_builtin_hwdb_lookup(dev, modalias, filter, test);
 103                 if (n > 0)
 104                         break;
 105         }
 106
 107         return n;
 108 }
 109
 110 static int builtin_hwdb(struct udev_device *dev, int argc, char *argv[], bool test) {
 111         static const struct option options[] = {
 112                 { "filter", required_argument, NULL, 'f' },
 113                 { "device", required_argument, NULL, 'd' },
 114                 { "subsystem", required_argument, NULL, 's' },
 115                 {}
 116         };
 117         const char *filter = NULL;
 118         const char *device = NULL;
 119         const char *subsystem = NULL;
 120         struct udev_device *srcdev;
 121
 122         if (!hwdb)
 123                 return EXIT_FAILURE;
 124
 125         for (;;) {
 126                 int option;
 127
 128                 option = getopt_long(argc, argv, "s", options, NULL);
 129                 if (option == -1)
 130                         break;
 131
 132                 switch (option) {
 133                 case 'f':
 134                         filter = optarg;
 135                         break;
 136
 137                 case 'd':
 138                         device = optarg;
 139                         break;
 140
 141                 case 's':
 142                         subsystem = optarg;
 143                         break;
 144                 }
 145         }
 146
 147         /* read data from another device than the device we will store the data */
 148         if (device) {
 149                 srcdev = udev_device_new_from_device_id(udev_device_get_udev(dev), device);
 150                 if (!srcdev)
 151                         return EXIT_FAILURE;
 152         } else
 153                 srcdev = dev;
 154
 155         if (udev_builtin_hwdb_search(dev, srcdev, subsystem, filter, test) < 0)
 156                 return EXIT_FAILURE;
 157         return EXIT_SUCCESS;
 158 }
 159
 160 /* called at udev startup and reload */
 161 static int builtin_hwdb_init(struct udev *udev)
 162 {
 163         if (hwdb)
 164                 return 0;
 165         hwdb = udev_hwdb_new(udev);
 166         if (!hwdb)
 167                 return -ENOMEM;
 168         return 0;
 169 }
 170
 171 /* called on udev shutdown and reload request */
 172 static void builtin_hwdb_exit(struct udev *udev)
 173 {
 174         hwdb = udev_hwdb_unref(hwdb);
 175 }
 176
 177 /* called every couple of seconds during event activity; 'true' if config has changed */
 178 static bool builtin_hwdb_validate(struct udev *udev)
 179 {
 180         return udev_hwdb_validate(hwdb);
 181 }
 182
 183 const struct udev_builtin udev_builtin_hwdb = {
 184         .name = "hwdb",
 185         .cmd = builtin_hwdb,
 186         .init = builtin_hwdb_init,
 187         .exit = builtin_hwdb_exit,
 188         .validate = builtin_hwdb_validate,
 189         .help = "hardware database",
 190 };