src/path-lookup.c

   1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
   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 <assert.h>
  23 #include <stdlib.h>
  24 #include <stdio.h>
  25 #include <unistd.h>
  26 #include <errno.h>
  27
  28 #include "util.h"
  29 #include "strv.h"
  30
  31 #include "path-lookup.h"
  32
  33 int session_config_home(char **config_home) {
  34         const char *e;
  35
  36         if ((e = getenv("XDG_CONFIG_HOME"))) {
  37                 if (asprintf(config_home, "%s/systemd/session", e) < 0)
  38                         return -ENOMEM;
  39
  40                 return 1;
  41         } else {
  42                 const char *home;
  43
  44                 if ((home = getenv("HOME"))) {
  45                         if (asprintf(config_home, "%s/.config/systemd/session", home) < 0)
  46                                 return -ENOMEM;
  47
  48                         return 1;
  49                 }
  50         }
  51
  52         return 0;
  53 }
  54
  55 static char** session_dirs(void) {
  56         const char *home, *e;
  57         char *config_home = NULL, *data_home = NULL;
  58         char **config_dirs = NULL, **data_dirs = NULL;
  59         char **r = NULL, **t;
  60
  61         /* Implement the mechanisms defined in
  62          *
  63          * http://standards.freedesktop.org/basedir-spec/basedir-spec-0.6.html
  64          *
  65          * We look in both the config and the data dirs because we
  66          * want to encourage that distributors ship their unit files
  67          * as data, and allow overriding as configuration.
  68          */
  69
  70         if (session_config_home(&config_home) < 0)
  71                 goto fail;
  72
  73         home = getenv("HOME");
  74
  75         if ((e = getenv("XDG_CONFIG_DIRS")))
  76                 if (!(config_dirs = strv_split(e, ":")))
  77                         goto fail;
  78
  79         /* We don't treat /etc/xdg/systemd here as the spec
  80          * suggests because we assume that that is a link to
  81          * /etc/systemd/ anyway. */
  82
  83         if ((e = getenv("XDG_DATA_HOME"))) {
  84                 if (asprintf(&data_home, "%s/systemd/session", e) < 0)
  85                         goto fail;
  86
  87         } else if (home) {
  88                 if (asprintf(&data_home, "%s/.local/share/systemd/session", home) < 0)
  89                         goto fail;
  90
  91                 /* There is really no need for two unit dirs in $HOME,
  92                  * except to be fully compliant with the XDG spec. We
  93                  * now try to link the two dirs, so that we can
  94                  * minimize disk seeks a little. Further down we'll
  95                  * then filter out this link, if it is actually is
  96                  * one. */
  97
  98                 mkdir_parents(data_home, 0777);
  99                 (void) symlink("../../../.config/systemd/session", data_home);
 100         }
 101
 102         if ((e = getenv("XDG_DATA_DIRS")))
 103                 data_dirs = strv_split(e, ":");
 104         else
 105                 data_dirs = strv_new("/usr/local/share", "/usr/share", NULL);
 106
 107         if (!data_dirs)
 108                 goto fail;
 109
 110         /* Now merge everything we found. */
 111         if (config_home) {
 112                 if (!(t = strv_append(r, config_home)))
 113                         goto fail;
 114                 strv_free(r);
 115                 r = t;
 116         }
 117
 118         if (!(t = strv_merge_concat(r, config_dirs, "/systemd/session")))
 119                 goto finish;
 120         strv_free(r);
 121         r = t;
 122
 123         if (!(t = strv_append(r, SESSION_CONFIG_UNIT_PATH)))
 124                 goto fail;
 125         strv_free(r);
 126         r = t;
 127
 128         if (data_home) {
 129                 if (!(t = strv_append(r, data_home)))
 130                         goto fail;
 131                 strv_free(r);
 132                 r = t;
 133         }
 134
 135         if (!(t = strv_merge_concat(r, data_dirs, "/systemd/session")))
 136                 goto fail;
 137         strv_free(r);
 138         r = t;
 139
 140         if (!(t = strv_append(r, SESSION_DATA_UNIT_PATH)))
 141                 goto fail;
 142         strv_free(r);
 143         r = t;
 144
 145         if (!strv_path_make_absolute_cwd(r))
 146             goto fail;
 147
 148 finish:
 149         free(config_home);
 150         strv_free(config_dirs);
 151         free(data_home);
 152         strv_free(data_dirs);
 153
 154         return r;
 155
 156 fail:
 157         strv_free(r);
 158         r = NULL;
 159         goto finish;
 160 }
 161
 162 int lookup_paths_init(LookupPaths *p, ManagerRunningAs running_as) {
 163         const char *e;
 164         char *t;
 165
 166         assert(p);
 167
 168         /* First priority is whatever has been passed to us via env
 169          * vars */
 170         if ((e = getenv("SYSTEMD_UNIT_PATH")))
 171                 if (!(p->unit_path = split_path_and_make_absolute(e)))
 172                         return -ENOMEM;
 173
 174         if (strv_isempty(p->unit_path)) {
 175
 176                 /* Nothing is set, so let's figure something out. */
 177                 strv_free(p->unit_path);
 178
 179                 if (running_as == MANAGER_SESSION) {
 180                         if (!(p->unit_path = session_dirs()))
 181                                 return -ENOMEM;
 182                 } else
 183                         if (!(p->unit_path = strv_new(
 184                                               SYSTEM_CONFIG_UNIT_PATH,
 185                                               "/etc/systemd/system",
 186                                               "/usr/local/share/systemd/system",
 187                                               "/usr/share/systemd/system",
 188                                               "/lib/systemd/system",
 189                                               SYSTEM_DATA_UNIT_PATH,
 190                                               NULL)))
 191                                 return -ENOMEM;
 192         }
 193
 194         if (running_as == MANAGER_SYSTEM) {
 195                 /* /etc/init.d/ compatibility does not matter to users */
 196
 197                 if ((e = getenv("SYSTEMD_SYSVINIT_PATH")))
 198                         if (!(p->sysvinit_path = split_path_and_make_absolute(e)))
 199                                 return -ENOMEM;
 200
 201                 if (strv_isempty(p->sysvinit_path)) {
 202                         strv_free(p->sysvinit_path);
 203
 204                         if (!(p->sysvinit_path = strv_new(
 205                                               SYSTEM_SYSVINIT_PATH,     /* /etc/init.d/ */
 206                                               NULL)))
 207                                 return -ENOMEM;
 208                 }
 209
 210                 if ((e = getenv("SYSTEMD_SYSVRCND_PATH")))
 211                         if (!(p->sysvrcnd_path = split_path_and_make_absolute(e)))
 212                                 return -ENOMEM;
 213
 214                 if (strv_isempty(p->sysvrcnd_path)) {
 215                         strv_free(p->sysvrcnd_path);
 216
 217                         if (!(p->sysvrcnd_path = strv_new(
 218                                               SYSTEM_SYSVRCND_PATH,     /* /etc/rcN.d/ */
 219                                               NULL)))
 220                                 return -ENOMEM;
 221                 }
 222         }
 223
 224         if (p->unit_path)
 225                 if (!strv_path_canonicalize(p->unit_path))
 226                         return -ENOMEM;
 227
 228         if (p->sysvinit_path)
 229                 if (!strv_path_canonicalize(p->sysvinit_path))
 230                         return -ENOMEM;
 231
 232         if (p->sysvrcnd_path)
 233                 if (!strv_path_canonicalize(p->sysvrcnd_path))
 234                         return -ENOMEM;
 235
 236         strv_uniq(p->unit_path);
 237         strv_uniq(p->sysvinit_path);
 238         strv_uniq(p->sysvrcnd_path);
 239
 240         if (!strv_isempty(p->unit_path)) {
 241
 242                 if (!(t = strv_join(p->unit_path, "\n\t")))
 243                         return -ENOMEM;
 244                 log_debug("Looking for unit files in:\n\t%s", t);
 245                 free(t);
 246         } else {
 247                 log_debug("Ignoring unit files.");
 248                 strv_free(p->unit_path);
 249                 p->unit_path = NULL;
 250         }
 251
 252         if (!strv_isempty(p->sysvinit_path)) {
 253
 254                 if (!(t = strv_join(p->sysvinit_path, "\n\t")))
 255                         return -ENOMEM;
 256
 257                 log_debug("Looking for SysV init scripts in:\n\t%s", t);
 258                 free(t);
 259         } else {
 260                 log_debug("Ignoring SysV init scripts.");
 261                 strv_free(p->sysvinit_path);
 262                 p->sysvinit_path = NULL;
 263         }
 264
 265         if (!strv_isempty(p->sysvrcnd_path)) {
 266
 267                 if (!(t = strv_join(p->sysvrcnd_path, "\n\t")))
 268                         return -ENOMEM;
 269
 270                 log_debug("Looking for SysV rcN.d links in:\n\t%s", t);
 271                 free(t);
 272         } else {
 273                 log_debug("Ignoring SysV rcN.d links.");
 274                 strv_free(p->sysvrcnd_path);
 275                 p->sysvrcnd_path = NULL;
 276         }
 277
 278         return 0;
 279 }
 280
 281 void lookup_paths_free(LookupPaths *p) {
 282         assert(p);
 283
 284         strv_free(p->unit_path);
 285         strv_free(p->sysvinit_path);
 286         strv_free(p->sysvrcnd_path);
 287
 288         p->unit_path = p->sysvinit_path = p->sysvrcnd_path = NULL;
 289 }