src/cgls.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <limits.h>
  23 #include <stdio.h>
  24 #include <unistd.h>
  25 #include <errno.h>
  26 #include <getopt.h>
  27 #include <string.h>
  28
  29 #include "cgroup-show.h"
  30 #include "cgroup-util.h"
  31 #include "log.h"
  32 #include "util.h"
  33
  34 static void help(void) {
  35
  36         printf("%s [OPTIONS...] [CGROUP...]\n\n"
  37                "Recursively show control group contents.\n\n"
  38                "  -h --help         Show this help\n",
  39                program_invocation_short_name);
  40 }
  41
  42 static int parse_argv(int argc, char *argv[]) {
  43
  44         static const struct option options[] = {
  45                 { "help",      no_argument,       NULL, 'h'         },
  46                 { NULL,        0,                 NULL, 0           }
  47         };
  48
  49         int c;
  50
  51         assert(argc >= 1);
  52         assert(argv);
  53
  54         while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {
  55
  56                 switch (c) {
  57
  58                 case 'h':
  59                         help();
  60                         return 0;
  61
  62                 case '?':
  63                         return -EINVAL;
  64
  65                 default:
  66                         log_error("Unknown option code %c", c);
  67                         return -EINVAL;
  68                 }
  69         }
  70
  71         return 1;
  72 }
  73
  74 int main(int argc, char *argv[]) {
  75         int r = 0, retval = EXIT_FAILURE;
  76
  77         log_parse_environment();
  78         log_open();
  79
  80         if ((r = parse_argv(argc, argv)) < 0)
  81                 goto finish;
  82         else if (r == 0) {
  83                 retval = EXIT_SUCCESS;
  84                 goto finish;
  85         }
  86
  87         if (optind < argc) {
  88                 unsigned i;
  89
  90                 for (i = (unsigned) optind; i < (unsigned) argc; i++) {
  91                         int q;
  92                         printf("%s:\n", argv[i]);
  93
  94                         if ((q = show_cgroup_by_path(argv[i], NULL, 0)) < 0)
  95                                 r = q;
  96                 }
  97
  98         } else {
  99                 char *p;
 100
 101                 if (!(p = get_current_dir_name())) {
 102                         log_error("Cannot determine current working directory: %m");
 103                         goto finish;
 104                 }
 105
 106                 if (path_startswith(p, "/sys/fs/cgroup")) {
 107                         printf("Working Directory %s:\n", p);
 108                         r = show_cgroup_by_path(p, NULL, 0);
 109                 } else {
 110                         char *root = NULL;
 111                         const char *t = NULL;
 112
 113                         if ((r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 1, &root)) < 0)
 114                                 t = "/";
 115                         else {
 116                                 if (endswith(root, "/system"))
 117                                         root[strlen(root)-7] = 0;
 118
 119                                 t = root[0] ? root : "/";
 120                         }
 121
 122                         r = show_cgroup(SYSTEMD_CGROUP_CONTROLLER, t, NULL, 0);
 123                         free(root);
 124                 }
 125
 126                 free(p);
 127         }
 128
 129         if (r < 0)
 130                 log_error("Failed to list cgroup tree: %s", strerror(-r));
 131
 132         retval = EXIT_SUCCESS;
 133
 134 finish:
 135
 136         return retval;
 137 }