src/cgls/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 Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 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   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser 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 "path-util.h"
  33 #include "util.h"
  34 #include "pager.h"
  35 #include "build.h"
  36
  37 static bool arg_no_pager = false;
  38 static bool arg_kernel_threads = false;
  39 static bool arg_all = false;
  40
  41 static void help(void) {
  42
  43         printf("%s [OPTIONS...] [CGROUP...]\n\n"
  44                "Recursively show control group contents.\n\n"
  45                "  -h --help           Show this help\n"
  46                "     --version        Show package version\n"
  47                "     --no-pager       Do not pipe output into a pager\n"
  48                "  -a --all            Show all groups, including empty\n"
  49                "  -k                  Include kernel threads in output\n",
  50                program_invocation_short_name);
  51 }
  52
  53 static int parse_argv(int argc, char *argv[]) {
  54
  55         enum {
  56                 ARG_NO_PAGER = 0x100,
  57                 ARG_VERSION
  58         };
  59
  60         static const struct option options[] = {
  61                 { "help",      no_argument,       NULL, 'h'          },
  62                 { "version",   no_argument,       NULL, ARG_VERSION  },
  63                 { "no-pager",  no_argument,       NULL, ARG_NO_PAGER },
  64                 { "all",       no_argument,       NULL, 'a'          },
  65                 { NULL,        0,                 NULL, 0            }
  66         };
  67
  68         int c;
  69
  70         assert(argc >= 1);
  71         assert(argv);
  72
  73         while ((c = getopt_long(argc, argv, "hka", options, NULL)) >= 0) {
  74
  75                 switch (c) {
  76
  77                 case 'h':
  78                         help();
  79                         return 0;
  80
  81                 case ARG_VERSION:
  82                         puts(PACKAGE_STRING);
  83                         puts(DISTRIBUTION);
  84                         puts(SYSTEMD_FEATURES);
  85                         return 0;
  86
  87                 case ARG_NO_PAGER:
  88                         arg_no_pager = true;
  89                         break;
  90
  91                 case 'a':
  92                         arg_all = true;
  93                         break;
  94
  95                 case 'k':
  96                         arg_kernel_threads = true;
  97                         break;
  98
  99                 case '?':
 100                         return -EINVAL;
 101
 102                 default:
 103                         log_error("Unknown option code %c", c);
 104                         return -EINVAL;
 105                 }
 106         }
 107
 108         return 1;
 109 }
 110
 111 int main(int argc, char *argv[]) {
 112         int r = 0, retval = EXIT_FAILURE;
 113
 114         log_parse_environment();
 115         log_open();
 116
 117         r = parse_argv(argc, argv);
 118         if (r < 0)
 119                 goto finish;
 120         else if (r == 0) {
 121                 retval = EXIT_SUCCESS;
 122                 goto finish;
 123         }
 124
 125         if (!arg_no_pager)
 126                 pager_open();
 127
 128         if (optind < argc) {
 129                 unsigned i;
 130
 131                 for (i = (unsigned) optind; i < (unsigned) argc; i++) {
 132                         int q;
 133                         printf("%s:\n", argv[i]);
 134
 135                         q = show_cgroup_by_path(argv[i], NULL, 0, arg_kernel_threads, arg_all);
 136                         if (q < 0)
 137                                 r = q;
 138                 }
 139
 140         } else {
 141                 char *p;
 142
 143                 p = get_current_dir_name();
 144                 if (!p) {
 145                         log_error("Cannot determine current working directory: %m");
 146                         goto finish;
 147                 }
 148
 149                 if (path_startswith(p, "/sys/fs/cgroup")) {
 150                         printf("Working Directory %s:\n", p);
 151                         r = show_cgroup_by_path(p, NULL, 0, arg_kernel_threads, arg_all);
 152                 } else {
 153                         char *root = NULL;
 154                         const char *t = NULL;
 155
 156                         r = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 1, &root);
 157                         if (r < 0)
 158                                 t = "/";
 159                         else {
 160                                 if (endswith(root, "/system"))
 161                                         root[strlen(root)-7] = 0;
 162
 163                                 t = root[0] ? root : "/";
 164                         }
 165
 166                         r = show_cgroup(SYSTEMD_CGROUP_CONTROLLER, t, NULL, 0, arg_kernel_threads, arg_all);
 167                         free(root);
 168                 }
 169
 170                 free(p);
 171         }
 172
 173         if (r < 0)
 174                 log_error("Failed to list cgroup tree: %s", strerror(-r));
 175
 176         retval = EXIT_SUCCESS;
 177
 178 finish:
 179         pager_close();
 180
 181         return retval;
 182 }