src/cgroup-show.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 <stdio.h>
  23 #include <string.h>
  24 #include <dirent.h>
  25 #include <errno.h>
  26
  27 #include "util.h"
  28 #include "macro.h"
  29 #include "cgroup-util.h"
  30 #include "cgroup-show.h"
  31
  32 static int compare(const void *a, const void *b) {
  33         const pid_t *p = a, *q = b;
  34
  35         if (*p < *q)
  36                 return -1;
  37         if (*p > *q)
  38                 return 1;
  39         return 0;
  40 }
  41
  42 static unsigned ilog10(unsigned long ul) {
  43         int n = 0;
  44
  45         while (ul > 0) {
  46                 n++;
  47                 ul /= 10;
  48         }
  49
  50         return n;
  51 }
  52
  53 static int show_cgroup_one_by_path(const char *path, const char *prefix, unsigned n_columns, bool more) {
  54         char *fn;
  55         FILE *f;
  56         size_t n = 0, n_allocated = 0;
  57         pid_t *pids = NULL;
  58         char *p;
  59         pid_t pid, biggest = 0;
  60         int r;
  61
  62         if (n_columns <= 0)
  63                 n_columns = columns();
  64
  65         if (!prefix)
  66                 prefix = "";
  67
  68         if ((r = cg_fix_path(path, &p)) < 0)
  69                 return r;
  70
  71         r = asprintf(&fn, "%s/cgroup.procs", p);
  72         free(p);
  73
  74         if (r < 0)
  75                 return -ENOMEM;
  76
  77         f = fopen(fn, "re");
  78         free(fn);
  79
  80         if (!f)
  81                 return -errno;
  82
  83         while ((r = cg_read_pid(f, &pid)) > 0) {
  84
  85                 if (n >= n_allocated) {
  86                         pid_t *npids;
  87
  88                         n_allocated = MAX(16U, n*2U);
  89
  90                         if (!(npids = realloc(pids, sizeof(pid_t) * n_allocated))) {
  91                                 r = -ENOMEM;
  92                                 goto finish;
  93                         }
  94
  95                         pids = npids;
  96                 }
  97
  98                 assert(n < n_allocated);
  99                 pids[n++] = pid;
 100
 101                 if (pid > biggest)
 102                         biggest = pid;
 103         }
 104
 105         if (r < 0)
 106                 goto finish;
 107
 108         if (n > 0) {
 109                 unsigned i, m;
 110
 111                 /* Filter duplicates */
 112                 m = 0;
 113                 for (i = 0; i < n; i++) {
 114                         unsigned j;
 115
 116                         for (j = i+1; j < n; j++)
 117                                 if (pids[i] == pids[j])
 118                                         break;
 119
 120                         if (j >= n)
 121                                 pids[m++] = pids[i];
 122                 }
 123                 n = m;
 124
 125                 /* And sort */
 126                 qsort(pids, n, sizeof(pid_t), compare);
 127
 128                 if (n_columns > 8)
 129                         n_columns -= 8;
 130                 else
 131                         n_columns = 20;
 132
 133                 for (i = 0; i < n; i++) {
 134                         char *t = NULL;
 135
 136                         get_process_cmdline(pids[i], n_columns, &t);
 137
 138                         printf("%s%s %*lu %s\n",
 139                                prefix,
 140                                (more || i < n-1) ? "\342\224\234" : "\342\224\224",
 141                                (int) ilog10(biggest),
 142                                (unsigned long) pids[i],
 143                                strna(t));
 144
 145                         free(t);
 146                 }
 147         }
 148
 149         r = 0;
 150
 151 finish:
 152         free(pids);
 153
 154         if (f)
 155                 fclose(f);
 156
 157         return r;
 158 }
 159
 160 int show_cgroup_by_path(const char *path, const char *prefix, unsigned n_columns) {
 161         DIR *d;
 162         char *last = NULL;
 163         char *p1 = NULL, *p2 = NULL, *fn = NULL, *gn = NULL;
 164         bool shown_pids = false;
 165         int r;
 166
 167         if (n_columns <= 0)
 168                 n_columns = columns();
 169
 170         if (!prefix)
 171                 prefix = "";
 172
 173         if ((r = cg_fix_path(path, &fn)) < 0)
 174                 return r;
 175
 176         if (!(d = opendir(fn))) {
 177                 free(fn);
 178                 return -errno;
 179         }
 180
 181         while ((r = cg_read_subgroup(d, &gn)) > 0) {
 182
 183                 if (!shown_pids) {
 184                         show_cgroup_one_by_path(path, prefix, n_columns, true);
 185                         shown_pids = true;
 186                 }
 187
 188                 if (last) {
 189                         printf("%s\342\224\234 %s\n", prefix, file_name_from_path(last));
 190
 191                         if (!p1)
 192                                 if (!(p1 = strappend(prefix, "\342\224\202 "))) {
 193                                         r = -ENOMEM;
 194                                         goto finish;
 195                                 }
 196
 197                         show_cgroup_by_path(last, p1, n_columns-2);
 198
 199                         free(last);
 200                         last = NULL;
 201                 }
 202
 203                 r = asprintf(&last, "%s/%s", fn, gn);
 204                 free(gn);
 205
 206                 if (r < 0) {
 207                         r = -ENOMEM;
 208                         goto finish;
 209                 }
 210         }
 211
 212         if (r < 0)
 213                 goto finish;
 214
 215         if (!shown_pids)
 216                 show_cgroup_one_by_path(path, prefix, n_columns, !!last);
 217
 218         if (last) {
 219                 printf("%s\342\224\224 %s\n", prefix, file_name_from_path(last));
 220
 221                 if (!p2)
 222                         if (!(p2 = strappend(prefix, "  "))) {
 223                                 r = -ENOMEM;
 224                                 goto finish;
 225                         }
 226
 227                 show_cgroup_by_path(last, p2, n_columns-2);
 228         }
 229
 230         r = 0;
 231
 232 finish:
 233         free(p1);
 234         free(p2);
 235         free(last);
 236         free(fn);
 237
 238         closedir(d);
 239
 240         return r;
 241 }
 242
 243 int show_cgroup(const char *controller, const char *path, const char *prefix, unsigned n_columns) {
 244         char *p;
 245         int r;
 246
 247         assert(controller);
 248         assert(path);
 249
 250         if ((r = cg_get_path(controller, path, NULL, &p)) < 0)
 251                 return r;
 252
 253         r = show_cgroup_by_path(p, prefix, n_columns);
 254         free(p);
 255
 256         return r;
 257 }