src/login/sysfs-show.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright 2010 Lennart Poettering
   4 ***/
   5
   6 #include <errno.h>
   7 #include <string.h>
   8
   9 #include "libudev.h"
  10
  11 #include "alloc-util.h"
  12 #include "locale-util.h"
  13 #include "path-util.h"
  14 #include "string-util.h"
  15 #include "sysfs-show.h"
  16 #include "terminal-util.h"
  17 #include "udev-util.h"
  18 #include "util.h"
  19
  20 static int show_sysfs_one(
  21                 struct udev *udev,
  22                 const char *seat,
  23                 struct udev_list_entry **item,
  24                 const char *sub,
  25                 const char *prefix,
  26                 unsigned n_columns,
  27                 OutputFlags flags) {
  28
  29         size_t max_width;
  30
  31         assert(udev);
  32         assert(seat);
  33         assert(item);
  34         assert(prefix);
  35
  36         if (flags & OUTPUT_FULL_WIDTH)
  37                 max_width = (size_t) -1;
  38         else if (n_columns < 10)
  39                 max_width = 10;
  40         else
  41                 max_width = n_columns;
  42
  43         while (*item) {
  44                 _cleanup_(udev_device_unrefp) struct udev_device *d = NULL;
  45                 struct udev_list_entry *next, *lookahead;
  46                 const char *sn, *name, *sysfs, *subsystem, *sysname;
  47                 _cleanup_free_ char *k = NULL, *l = NULL;
  48                 bool is_master;
  49
  50                 sysfs = udev_list_entry_get_name(*item);
  51                 if (!path_startswith(sysfs, sub))
  52                         return 0;
  53
  54                 d = udev_device_new_from_syspath(udev, sysfs);
  55                 if (!d) {
  56                         *item = udev_list_entry_get_next(*item);
  57                         continue;
  58                 }
  59
  60                 sn = udev_device_get_property_value(d, "ID_SEAT");
  61                 if (isempty(sn))
  62                         sn = "seat0";
  63
  64                 /* Explicitly also check for tag 'seat' here */
  65                 if (!streq(seat, sn) || !udev_device_has_tag(d, "seat")) {
  66                         *item = udev_list_entry_get_next(*item);
  67                         continue;
  68                 }
  69
  70                 is_master = udev_device_has_tag(d, "master-of-seat");
  71
  72                 name = udev_device_get_sysattr_value(d, "name");
  73                 if (!name)
  74                         name = udev_device_get_sysattr_value(d, "id");
  75                 subsystem = udev_device_get_subsystem(d);
  76                 sysname = udev_device_get_sysname(d);
  77
  78                 /* Look if there's more coming after this */
  79                 lookahead = next = udev_list_entry_get_next(*item);
  80                 while (lookahead) {
  81                         const char *lookahead_sysfs;
  82
  83                         lookahead_sysfs = udev_list_entry_get_name(lookahead);
  84
  85                         if (path_startswith(lookahead_sysfs, sub) &&
  86                             !path_startswith(lookahead_sysfs, sysfs)) {
  87                                 _cleanup_(udev_device_unrefp) struct udev_device *lookahead_d = NULL;
  88
  89                                 lookahead_d = udev_device_new_from_syspath(udev, lookahead_sysfs);
  90                                 if (lookahead_d) {
  91                                         const char *lookahead_sn;
  92
  93                                         lookahead_sn = udev_device_get_property_value(d, "ID_SEAT");
  94                                         if (isempty(lookahead_sn))
  95                                                 lookahead_sn = "seat0";
  96
  97                                         if (streq(seat, lookahead_sn) && udev_device_has_tag(lookahead_d, "seat"))
  98                                                 break;
  99                                 }
 100                         }
 101
 102                         lookahead = udev_list_entry_get_next(lookahead);
 103                 }
 104
 105                 k = ellipsize(sysfs, max_width, 20);
 106                 if (!k)
 107                         return -ENOMEM;
 108
 109                 printf("%s%s%s\n", prefix, special_glyph(lookahead ? TREE_BRANCH : TREE_RIGHT), k);
 110
 111                 if (asprintf(&l,
 112                              "%s%s:%s%s%s%s",
 113                              is_master ? "[MASTER] " : "",
 114                              subsystem, sysname,
 115                              name ? " \"" : "", strempty(name), name ? "\"" : "") < 0)
 116                         return -ENOMEM;
 117
 118                 free(k);
 119                 k = ellipsize(l, max_width, 70);
 120                 if (!k)
 121                         return -ENOMEM;
 122
 123                 printf("%s%s%s\n", prefix, lookahead ? special_glyph(TREE_VERTICAL) : "  ", k);
 124
 125                 *item = next;
 126                 if (*item) {
 127                         _cleanup_free_ char *p = NULL;
 128
 129                         p = strappend(prefix, lookahead ? special_glyph(TREE_VERTICAL) : "  ");
 130                         if (!p)
 131                                 return -ENOMEM;
 132
 133                         show_sysfs_one(udev, seat, item, sysfs, p,
 134                                        n_columns == (unsigned) -1 || n_columns < 2 ? n_columns : n_columns - 2,
 135                                        flags);
 136                 }
 137         }
 138
 139         return 0;
 140 }
 141
 142 int show_sysfs(const char *seat, const char *prefix, unsigned n_columns, OutputFlags flags) {
 143         _cleanup_(udev_enumerate_unrefp) struct udev_enumerate *e = NULL;
 144         _cleanup_(udev_unrefp) struct udev *udev = NULL;
 145         struct udev_list_entry *first = NULL;
 146         int r;
 147
 148         if (n_columns <= 0)
 149                 n_columns = columns();
 150
 151         prefix = strempty(prefix);
 152
 153         if (isempty(seat))
 154                 seat = "seat0";
 155
 156         udev = udev_new();
 157         if (!udev)
 158                 return -ENOMEM;
 159
 160         e = udev_enumerate_new(udev);
 161         if (!e)
 162                 return -ENOMEM;
 163
 164         if (!streq(seat, "seat0"))
 165                 r = udev_enumerate_add_match_tag(e, seat);
 166         else
 167                 r = udev_enumerate_add_match_tag(e, "seat");
 168         if (r < 0)
 169                 return r;
 170
 171         r = udev_enumerate_add_match_is_initialized(e);
 172         if (r < 0)
 173                 return r;
 174
 175         r = udev_enumerate_scan_devices(e);
 176         if (r < 0)
 177                 return r;
 178
 179         first = udev_enumerate_get_list_entry(e);
 180         if (first)
 181                 show_sysfs_one(udev, seat, &first, "/", prefix, n_columns, flags);
 182         else
 183                 printf("%s%s%s\n", prefix, special_glyph(TREE_RIGHT), "(none)");
 184
 185         return r;
 186 }