src/login/sysfs-show.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2010 Lennart Poettering
   6 ***/
   7
   8 #include <errno.h>
   9 #include <string.h>
  10
  11 #if 0 /// elogind needs the systems udev header
  12 #include "libudev.h"
  13 #else
  14 #include <libudev.h>
  15 #endif // 0
  16
  17 #include "alloc-util.h"
  18 #include "locale-util.h"
  19 #include "path-util.h"
  20 #include "string-util.h"
  21 #include "sysfs-show.h"
  22 #include "terminal-util.h"
  23 #include "udev-util.h"
  24 #include "util.h"
  25
  26 static int show_sysfs_one(
  27                 struct udev *udev,
  28                 const char *seat,
  29                 struct udev_list_entry **item,
  30                 const char *sub,
  31                 const char *prefix,
  32                 unsigned n_columns,
  33                 OutputFlags flags) {
  34
  35         size_t max_width;
  36
  37         assert(udev);
  38         assert(seat);
  39         assert(item);
  40         assert(prefix);
  41
  42         if (flags & OUTPUT_FULL_WIDTH)
  43                 max_width = (size_t) -1;
  44         else if (n_columns < 10)
  45                 max_width = 10;
  46         else
  47                 max_width = n_columns;
  48
  49         while (*item) {
  50                 _cleanup_(udev_device_unrefp) struct udev_device *d = NULL;
  51                 struct udev_list_entry *next, *lookahead;
  52                 const char *sn, *name, *sysfs, *subsystem, *sysname;
  53                 _cleanup_free_ char *k = NULL, *l = NULL;
  54                 bool is_master;
  55
  56                 sysfs = udev_list_entry_get_name(*item);
  57                 if (!path_startswith(sysfs, sub))
  58                         return 0;
  59
  60                 d = udev_device_new_from_syspath(udev, sysfs);
  61                 if (!d) {
  62                         *item = udev_list_entry_get_next(*item);
  63                         continue;
  64                 }
  65
  66                 sn = udev_device_get_property_value(d, "ID_SEAT");
  67                 if (isempty(sn))
  68                         sn = "seat0";
  69
  70                 /* Explicitly also check for tag 'seat' here */
  71                 if (!streq(seat, sn) || !udev_device_has_tag(d, "seat")) {
  72                         *item = udev_list_entry_get_next(*item);
  73                         continue;
  74                 }
  75
  76                 is_master = udev_device_has_tag(d, "master-of-seat");
  77
  78                 name = udev_device_get_sysattr_value(d, "name");
  79                 if (!name)
  80                         name = udev_device_get_sysattr_value(d, "id");
  81                 subsystem = udev_device_get_subsystem(d);
  82                 sysname = udev_device_get_sysname(d);
  83
  84                 /* Look if there's more coming after this */
  85                 lookahead = next = udev_list_entry_get_next(*item);
  86                 while (lookahead) {
  87                         const char *lookahead_sysfs;
  88
  89                         lookahead_sysfs = udev_list_entry_get_name(lookahead);
  90
  91                         if (path_startswith(lookahead_sysfs, sub) &&
  92                             !path_startswith(lookahead_sysfs, sysfs)) {
  93                                 _cleanup_(udev_device_unrefp) struct udev_device *lookahead_d = NULL;
  94
  95                                 lookahead_d = udev_device_new_from_syspath(udev, lookahead_sysfs);
  96                                 if (lookahead_d) {
  97                                         const char *lookahead_sn;
  98
  99                                         lookahead_sn = udev_device_get_property_value(d, "ID_SEAT");
 100                                         if (isempty(lookahead_sn))
 101                                                 lookahead_sn = "seat0";
 102
 103                                         if (streq(seat, lookahead_sn) && udev_device_has_tag(lookahead_d, "seat"))
 104                                                 break;
 105                                 }
 106                         }
 107
 108                         lookahead = udev_list_entry_get_next(lookahead);
 109                 }
 110
 111                 k = ellipsize(sysfs, max_width, 20);
 112                 if (!k)
 113                         return -ENOMEM;
 114
 115                 printf("%s%s%s\n", prefix, special_glyph(lookahead ? TREE_BRANCH : TREE_RIGHT), k);
 116
 117                 if (asprintf(&l,
 118                              "%s%s:%s%s%s%s",
 119                              is_master ? "[MASTER] " : "",
 120                              subsystem, sysname,
 121                              name ? " \"" : "", strempty(name), name ? "\"" : "") < 0)
 122                         return -ENOMEM;
 123
 124                 free(k);
 125                 k = ellipsize(l, max_width, 70);
 126                 if (!k)
 127                         return -ENOMEM;
 128
 129                 printf("%s%s%s\n", prefix, lookahead ? special_glyph(TREE_VERTICAL) : "  ", k);
 130
 131                 *item = next;
 132                 if (*item) {
 133                         _cleanup_free_ char *p = NULL;
 134
 135                         p = strappend(prefix, lookahead ? special_glyph(TREE_VERTICAL) : "  ");
 136                         if (!p)
 137                                 return -ENOMEM;
 138
 139                         show_sysfs_one(udev, seat, item, sysfs, p,
 140                                        n_columns == (unsigned) -1 || n_columns < 2 ? n_columns : n_columns - 2,
 141                                        flags);
 142                 }
 143         }
 144
 145         return 0;
 146 }
 147
 148 int show_sysfs(const char *seat, const char *prefix, unsigned n_columns, OutputFlags flags) {
 149         _cleanup_(udev_enumerate_unrefp) struct udev_enumerate *e = NULL;
 150         _cleanup_(udev_unrefp) struct udev *udev = NULL;
 151         struct udev_list_entry *first = NULL;
 152         int r;
 153
 154         if (n_columns <= 0)
 155                 n_columns = columns();
 156
 157         prefix = strempty(prefix);
 158
 159         if (isempty(seat))
 160                 seat = "seat0";
 161
 162         udev = udev_new();
 163         if (!udev)
 164                 return -ENOMEM;
 165
 166         e = udev_enumerate_new(udev);
 167         if (!e)
 168                 return -ENOMEM;
 169
 170         if (!streq(seat, "seat0"))
 171                 r = udev_enumerate_add_match_tag(e, seat);
 172         else
 173                 r = udev_enumerate_add_match_tag(e, "seat");
 174         if (r < 0)
 175                 return r;
 176
 177         r = udev_enumerate_add_match_is_initialized(e);
 178         if (r < 0)
 179                 return r;
 180
 181         r = udev_enumerate_scan_devices(e);
 182         if (r < 0)
 183                 return r;
 184
 185         first = udev_enumerate_get_list_entry(e);
 186         if (first)
 187                 show_sysfs_one(udev, seat, &first, "/", prefix, n_columns, flags);
 188         else
 189                 printf("%s%s%s\n", prefix, special_glyph(TREE_RIGHT), "(none)");
 190
 191         return r;
 192 }