src/cgls/cgls.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <errno.h>
   4 #include <getopt.h>
   5 #include <stdio.h>
   6 #include <unistd.h>
   7
   8 #include "sd-bus.h"
   9
  10 #include "alloc-util.h"
  11 #include "bus-util.h"
  12 #include "cgroup-show.h"
  13 #include "cgroup-util.h"
  14 #include "fileio.h"
  15 #include "log.h"
  16 #include "main-func.h"
  17 #include "output-mode.h"
  18 #include "pager.h"
  19 #include "path-util.h"
  20 #include "pretty-print.h"
  21 #include "strv.h"
  22 #include "unit-name.h"
  23 #include "util.h"
  24
  25 static PagerFlags arg_pager_flags = 0;
  26 static bool arg_kernel_threads = false;
  27 static bool arg_all = false;
  28
  29 static enum {
  30         SHOW_UNIT_NONE,
  31         SHOW_UNIT_SYSTEM,
  32         SHOW_UNIT_USER,
  33 } arg_show_unit = SHOW_UNIT_NONE;
  34 static char **arg_names = NULL;
  35
  36 static int arg_full = -1;
  37 static const char* arg_machine = NULL;
  38
  39 STATIC_DESTRUCTOR_REGISTER(arg_names, freep); /* don't free the strings */
  40
  41 static int help(void) {
  42         _cleanup_free_ char *link = NULL;
  43         int r;
  44
  45         r = terminal_urlify_man("systemd-cgls", "1", &link);
  46         if (r < 0)
  47                 return log_oom();
  48
  49         printf("%s [OPTIONS...] [CGROUP...]\n\n"
  50                "Recursively show control group contents.\n\n"
  51                "  -h --help           Show this help\n"
  52                "     --version        Show package version\n"
  53                "     --no-pager       Do not pipe output into a pager\n"
  54                "  -a --all            Show all groups, including empty\n"
  55                "  -u --unit           Show the subtrees of specified system units\n"
  56                "     --user-unit      Show the subtrees of specified user units\n"
  57                "  -l --full           Do not ellipsize output\n"
  58                "  -k                  Include kernel threads in output\n"
  59                "  -M --machine=       Show container\n"
  60                "\nSee the %s for details.\n",
  61                program_invocation_short_name,
  62                link);
  63
  64         return 0;
  65 }
  66
  67 static int parse_argv(int argc, char *argv[]) {
  68
  69         enum {
  70                 ARG_NO_PAGER = 0x100,
  71                 ARG_VERSION,
  72                 ARG_USER_UNIT,
  73         };
  74
  75         static const struct option options[] = {
  76                 { "help",      no_argument,       NULL, 'h'           },
  77                 { "version",   no_argument,       NULL, ARG_VERSION   },
  78                 { "no-pager",  no_argument,       NULL, ARG_NO_PAGER  },
  79                 { "all",       no_argument,       NULL, 'a'           },
  80                 { "full",      no_argument,       NULL, 'l'           },
  81                 { "machine",   required_argument, NULL, 'M'           },
  82                 { "unit",      optional_argument, NULL, 'u'           },
  83                 { "user-unit", optional_argument, NULL, ARG_USER_UNIT },
  84                 {}
  85         };
  86
  87         int c;
  88
  89         assert(argc >= 1);
  90         assert(argv);
  91
  92         while ((c = getopt_long(argc, argv, "-hkalM:u::", options, NULL)) >= 0)
  93
  94                 switch (c) {
  95
  96                 case 'h':
  97                         return help();
  98
  99                 case ARG_VERSION:
 100                         return version();
 101
 102                 case ARG_NO_PAGER:
 103                         arg_pager_flags |= PAGER_DISABLE;
 104                         break;
 105
 106                 case 'a':
 107                         arg_all = true;
 108                         break;
 109
 110                 case 'u':
 111                         arg_show_unit = SHOW_UNIT_SYSTEM;
 112                         if (strv_push(&arg_names, optarg) < 0) /* push optarg if not empty */
 113                                 return log_oom();
 114                         break;
 115
 116                 case ARG_USER_UNIT:
 117                         arg_show_unit = SHOW_UNIT_USER;
 118                         if (strv_push(&arg_names, optarg) < 0) /* push optarg if not empty */
 119                                 return log_oom();
 120                         break;
 121
 122                 case 1:
 123                         /* positional argument */
 124                         if (strv_push(&arg_names, optarg) < 0)
 125                                 return log_oom();
 126                         break;
 127
 128                 case 'l':
 129                         arg_full = true;
 130                         break;
 131
 132                 case 'k':
 133                         arg_kernel_threads = true;
 134                         break;
 135
 136                 case 'M':
 137                         arg_machine = optarg;
 138                         break;
 139
 140                 case '?':
 141                         return -EINVAL;
 142
 143                 default:
 144                         assert_not_reached("Unhandled option");
 145                 }
 146
 147         if (arg_machine && arg_show_unit != SHOW_UNIT_NONE)
 148                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 149                                        "Cannot combine --unit or --user-unit with --machine=.");
 150
 151         return 1;
 152 }
 153
 154 static void show_cg_info(const char *controller, const char *path) {
 155
 156         if (cg_all_unified() == 0 && controller && !streq(controller, SYSTEMD_CGROUP_CONTROLLER))
 157                 printf("Controller %s; ", controller);
 158
 159         printf("Control group %s:\n", empty_to_root(path));
 160         fflush(stdout);
 161 }
 162
 163 static int run(int argc, char *argv[]) {
 164         int r, output_flags;
 165
 166         log_setup();
 167
 168         r = parse_argv(argc, argv);
 169         if (r <= 0)
 170                 return r;
 171
 172         r = pager_open(arg_pager_flags);
 173         if (r > 0 && arg_full < 0)
 174                 arg_full = true;
 175
 176         output_flags =
 177                 arg_all * OUTPUT_SHOW_ALL |
 178                 (arg_full > 0) * OUTPUT_FULL_WIDTH |
 179                 arg_kernel_threads * OUTPUT_KERNEL_THREADS;
 180
 181         if (arg_names) {
 182                 _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
 183                 _cleanup_free_ char *root = NULL;
 184                 char **name;
 185
 186                 STRV_FOREACH(name, arg_names) {
 187                         int q;
 188
 189                         if (arg_show_unit != SHOW_UNIT_NONE) {
 190                                 /* Command line arguments are unit names */
 191                                 _cleanup_free_ char *cgroup = NULL;
 192
 193                                 if (!bus) {
 194                                         /* Connect to the bus only if necessary */
 195                                         r = bus_connect_transport_systemd(BUS_TRANSPORT_LOCAL, NULL,
 196                                                                           arg_show_unit == SHOW_UNIT_USER,
 197                                                                           &bus);
 198                                         if (r < 0)
 199                                                 return bus_log_connect_error(r);
 200                                 }
 201
 202                                 q = show_cgroup_get_unit_path_and_warn(bus, *name, &cgroup);
 203                                 if (q < 0)
 204                                         goto failed;
 205
 206                                 if (isempty(cgroup)) {
 207                                         log_warning("Unit %s not found.", *name);
 208                                         q = -ENOENT;
 209                                         goto failed;
 210                                 }
 211
 212                                 printf("Unit %s (%s):\n", *name, cgroup);
 213                                 fflush(stdout);
 214
 215                                 q = show_cgroup_by_path(cgroup, NULL, 0, output_flags);
 216
 217                         } else if (path_startswith(*name, "/sys/fs/cgroup")) {
 218
 219                                 printf("Directory %s:\n", *name);
 220                                 fflush(stdout);
 221
 222                                 q = show_cgroup_by_path(*name, NULL, 0, output_flags);
 223                         } else {
 224                                 _cleanup_free_ char *c = NULL, *p = NULL, *j = NULL;
 225                                 const char *controller, *path;
 226
 227                                 if (!root) {
 228                                         /* Query root only if needed, treat error as fatal */
 229                                         r = show_cgroup_get_path_and_warn(arg_machine, NULL, &root);
 230                                         if (r < 0)
 231                                                 return log_error_errno(r, "Failed to list cgroup tree: %m");
 232                                 }
 233
 234                                 q = cg_split_spec(*name, &c, &p);
 235                                 if (q < 0) {
 236                                         log_error_errno(q, "Failed to split argument %s: %m", *name);
 237                                         goto failed;
 238                                 }
 239
 240                                 controller = c ?: SYSTEMD_CGROUP_CONTROLLER;
 241                                 if (p) {
 242                                         j = path_join(root, p);
 243                                         if (!j)
 244                                                 return log_oom();
 245
 246                                         path_simplify(j, false);
 247                                         path = j;
 248                                 } else
 249                                         path = root;
 250
 251                                 show_cg_info(controller, path);
 252
 253                                 q = show_cgroup(controller, path, NULL, 0, output_flags);
 254                         }
 255
 256                 failed:
 257                         if (q < 0 && r >= 0)
 258                                 r = q;
 259                 }
 260
 261         } else {
 262                 bool done = false;
 263
 264                 if (!arg_machine)  {
 265                         _cleanup_free_ char *cwd = NULL;
 266
 267                         r = safe_getcwd(&cwd);
 268                         if (r < 0)
 269                                 return log_error_errno(r, "Cannot determine current working directory: %m");
 270
 271                         if (path_startswith(cwd, "/sys/fs/cgroup")) {
 272                                 printf("Working directory %s:\n", cwd);
 273                                 fflush(stdout);
 274
 275                                 r = show_cgroup_by_path(cwd, NULL, 0, output_flags);
 276                                 done = true;
 277                         }
 278                 }
 279
 280                 if (!done) {
 281                         _cleanup_free_ char *root = NULL;
 282
 283                         r = show_cgroup_get_path_and_warn(arg_machine, NULL, &root);
 284                         if (r < 0)
 285                                 return log_error_errno(r, "Failed to list cgroup tree: %m");
 286
 287                         show_cg_info(SYSTEMD_CGROUP_CONTROLLER, root);
 288
 289                         printf("-.slice\n");
 290                         r = show_cgroup(SYSTEMD_CGROUP_CONTROLLER, root, NULL, 0, output_flags);
 291                 }
 292         }
 293         if (r < 0)
 294                 return log_error_errno(r, "Failed to list cgroup tree: %m");
 295
 296         return 0;
 297 }
 298
 299 DEFINE_MAIN_FUNCTION(run);