src/path-lookup.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 <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 user_config_home(char **config_home) {
  34         const char *e;
  35
  36         if ((e = getenv("XDG_CONFIG_HOME"))) {
  37                 if (asprintf(config_home, "%s/systemd/user", 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/user", home) < 0)
  46                                 return -ENOMEM;
  47
  48                         return 1;
  49                 }
  50         }
  51
  52         return 0;
  53 }
  54
  55 static char** user_dirs(void) {
  56         const char * const config_unit_paths[] = {
  57                 "/run/systemd/user",
  58                 USER_CONFIG_UNIT_PATH,
  59                 "/etc/systemd/user",
  60                 NULL
  61         };
  62
  63         const char * const data_unit_paths[] = {
  64                 "/usr/local/lib/systemd/user",
  65                 "/usr/local/share/systemd/user",
  66                 USER_DATA_UNIT_PATH,
  67                 "/usr/lib/systemd/user",
  68                 "/usr/share/systemd/user",
  69                 NULL
  70         };
  71
  72         const char *home, *e;
  73         char *config_home = NULL, *data_home = NULL;
  74         char **config_dirs = NULL, **data_dirs = NULL;
  75         char **r = NULL, **t;
  76
  77         /* Implement the mechanisms defined in
  78          *
  79          * http://standards.freedesktop.org/basedir-spec/basedir-spec-0.6.html
  80          *
  81          * We look in both the config and the data dirs because we
  82          * want to encourage that distributors ship their unit files
  83          * as data, and allow overriding as configuration.
  84          */
  85
  86         if (user_config_home(&config_home) < 0)
  87                 goto fail;
  88
  89         home = getenv("HOME");
  90
  91         if ((e = getenv("XDG_CONFIG_DIRS")))
  92                 if (!(config_dirs = strv_split(e, ":")))
  93                         goto fail;
  94
  95         /* We don't treat /etc/xdg/systemd here as the spec
  96          * suggests because we assume that that is a link to
  97          * /etc/systemd/ anyway. */
  98
  99         if ((e = getenv("XDG_DATA_HOME"))) {
 100                 if (asprintf(&data_home, "%s/systemd/user", e) < 0)
 101                         goto fail;
 102
 103         } else if (home) {
 104                 if (asprintf(&data_home, "%s/.local/share/systemd/user", home) < 0)
 105                         goto fail;
 106
 107                 /* There is really no need for two unit dirs in $HOME,
 108                  * except to be fully compliant with the XDG spec. We
 109                  * now try to link the two dirs, so that we can
 110                  * minimize disk seeks a little. Further down we'll
 111                  * then filter out this link, if it is actually is
 112                  * one. */
 113
 114                 mkdir_parents(data_home, 0777);
 115                 (void) symlink("../../../.config/systemd/user", data_home);
 116         }
 117
 118         if ((e = getenv("XDG_DATA_DIRS")))
 119                 data_dirs = strv_split(e, ":");
 120         else
 121                 data_dirs = strv_new("/usr/local/share",
 122                                      "/usr/share",
 123                                      NULL);
 124
 125         if (!data_dirs)
 126                 goto fail;
 127
 128         /* Now merge everything we found. */
 129         if (config_home) {
 130                 if (!(t = strv_append(r, config_home)))
 131                         goto fail;
 132                 strv_free(r);
 133                 r = t;
 134         }
 135
 136         if (!strv_isempty(config_dirs)) {
 137                 if (!(t = strv_merge_concat(r, config_dirs, "/systemd/user")))
 138                         goto finish;
 139                 strv_free(r);
 140                 r = t;
 141         }
 142
 143         if (!(t = strv_merge(r, (char**) config_unit_paths)))
 144                 goto fail;
 145         strv_free(r);
 146         r = t;
 147
 148         if (data_home) {
 149                 if (!(t = strv_append(r, data_home)))
 150                         goto fail;
 151                 strv_free(r);
 152                 r = t;
 153         }
 154
 155         if (!strv_isempty(data_dirs)) {
 156                 if (!(t = strv_merge_concat(r, data_dirs, "/systemd/user")))
 157                         goto fail;
 158                 strv_free(r);
 159                 r = t;
 160         }
 161
 162         if (!(t = strv_merge(r, (char**) data_unit_paths)))
 163                 goto fail;
 164         strv_free(r);
 165         r = t;
 166
 167         if (!strv_path_make_absolute_cwd(r))
 168             goto fail;
 169
 170 finish:
 171         free(config_home);
 172         strv_free(config_dirs);
 173         free(data_home);
 174         strv_free(data_dirs);
 175
 176         return r;
 177
 178 fail:
 179         strv_free(r);
 180         r = NULL;
 181         goto finish;
 182 }
 183
 184 int lookup_paths_init(LookupPaths *p, ManagerRunningAs running_as, bool personal) {
 185         const char *e;
 186         char *t;
 187
 188         assert(p);
 189
 190         /* First priority is whatever has been passed to us via env
 191          * vars */
 192         if ((e = getenv("SYSTEMD_UNIT_PATH")))
 193                 if (!(p->unit_path = split_path_and_make_absolute(e)))
 194                         return -ENOMEM;
 195
 196         if (strv_isempty(p->unit_path)) {
 197
 198                 /* Nothing is set, so let's figure something out. */
 199                 strv_free(p->unit_path);
 200
 201                 if (running_as == MANAGER_USER) {
 202
 203                         if (personal)
 204                                 p->unit_path = user_dirs();
 205                         else
 206                                 p->unit_path = strv_new(
 207                                                 /* If you modify this you also want to modify
 208                                                  * systemduserunitpath= in systemd.pc.in, and
 209                                                  * the arrays in user_dirs() above! */
 210                                                 "/run/systemd/user",
 211                                                 USER_CONFIG_UNIT_PATH,
 212                                                 "/etc/systemd/user",
 213                                                 "/usr/local/lib/systemd/user",
 214                                                 "/usr/local/share/systemd/user",
 215                                                 USER_DATA_UNIT_PATH,
 216                                                 "/usr/lib/systemd/user",
 217                                                 "/usr/share/systemd/user",
 218                                                 NULL);
 219
 220                         if (!p->unit_path)
 221                                 return -ENOMEM;
 222
 223                 } else
 224                         if (!(p->unit_path = strv_new(
 225                                               /* If you modify this you also want to modify
 226                                                * systemdsystemunitpath= in systemd.pc.in! */
 227                                               "/run/systemd/system",
 228                                               SYSTEM_CONFIG_UNIT_PATH,
 229                                               "/etc/systemd/system",
 230                                               "/usr/local/lib/systemd/system",
 231                                               "/usr/lib/systemd/system",
 232                                               SYSTEM_DATA_UNIT_PATH,
 233 #ifdef HAVE_SPLIT_USR
 234                                               "/lib/systemd/system",
 235 #endif
 236                                               NULL)))
 237                                 return -ENOMEM;
 238         }
 239
 240         if (p->unit_path)
 241                 if (!strv_path_canonicalize(p->unit_path))
 242                         return -ENOMEM;
 243
 244         strv_uniq(p->unit_path);
 245         strv_path_remove_empty(p->unit_path);
 246
 247         if (!strv_isempty(p->unit_path)) {
 248
 249                 if (!(t = strv_join(p->unit_path, "\n\t")))
 250                         return -ENOMEM;
 251                 log_debug("Looking for unit files in:\n\t%s", t);
 252                 free(t);
 253         } else {
 254                 log_debug("Ignoring unit files.");
 255                 strv_free(p->unit_path);
 256                 p->unit_path = NULL;
 257         }
 258
 259         if (running_as == MANAGER_SYSTEM) {
 260 #ifdef HAVE_SYSV_COMPAT
 261                 /* /etc/init.d/ compatibility does not matter to users */
 262
 263                 if ((e = getenv("SYSTEMD_SYSVINIT_PATH")))
 264                         if (!(p->sysvinit_path = split_path_and_make_absolute(e)))
 265                                 return -ENOMEM;
 266
 267                 if (strv_isempty(p->sysvinit_path)) {
 268                         strv_free(p->sysvinit_path);
 269
 270                         if (!(p->sysvinit_path = strv_new(
 271                                               SYSTEM_SYSVINIT_PATH,     /* /etc/init.d/ */
 272                                               NULL)))
 273                                 return -ENOMEM;
 274                 }
 275
 276                 if ((e = getenv("SYSTEMD_SYSVRCND_PATH")))
 277                         if (!(p->sysvrcnd_path = split_path_and_make_absolute(e)))
 278                                 return -ENOMEM;
 279
 280                 if (strv_isempty(p->sysvrcnd_path)) {
 281                         strv_free(p->sysvrcnd_path);
 282
 283                         if (!(p->sysvrcnd_path = strv_new(
 284                                               SYSTEM_SYSVRCND_PATH,     /* /etc/rcN.d/ */
 285                                               NULL)))
 286                                 return -ENOMEM;
 287                 }
 288
 289                 if (p->sysvinit_path)
 290                         if (!strv_path_canonicalize(p->sysvinit_path))
 291                                 return -ENOMEM;
 292
 293                 if (p->sysvrcnd_path)
 294                         if (!strv_path_canonicalize(p->sysvrcnd_path))
 295                                 return -ENOMEM;
 296
 297                 strv_uniq(p->sysvinit_path);
 298                 strv_uniq(p->sysvrcnd_path);
 299
 300                 strv_path_remove_empty(p->sysvinit_path);
 301                 strv_path_remove_empty(p->sysvrcnd_path);
 302
 303                 if (!strv_isempty(p->sysvinit_path)) {
 304
 305                         if (!(t = strv_join(p->sysvinit_path, "\n\t")))
 306                                 return -ENOMEM;
 307
 308                         log_debug("Looking for SysV init scripts in:\n\t%s", t);
 309                         free(t);
 310                 } else {
 311                         log_debug("Ignoring SysV init scripts.");
 312                         strv_free(p->sysvinit_path);
 313                         p->sysvinit_path = NULL;
 314                 }
 315
 316                 if (!strv_isempty(p->sysvrcnd_path)) {
 317
 318                         if (!(t = strv_join(p->sysvrcnd_path, "\n\t")))
 319                                 return -ENOMEM;
 320
 321                         log_debug("Looking for SysV rcN.d links in:\n\t%s", t);
 322                         free(t);
 323                 } else {
 324                         log_debug("Ignoring SysV rcN.d links.");
 325                         strv_free(p->sysvrcnd_path);
 326                         p->sysvrcnd_path = NULL;
 327                 }
 328 #else
 329                 log_debug("Disabled SysV init scripts and rcN.d links support");
 330 #endif
 331         }
 332
 333         return 0;
 334 }
 335
 336 void lookup_paths_free(LookupPaths *p) {
 337         assert(p);
 338
 339         strv_free(p->unit_path);
 340         p->unit_path = NULL;
 341
 342 #ifdef HAVE_SYSV_COMPAT
 343         strv_free(p->sysvinit_path);
 344         strv_free(p->sysvrcnd_path);
 345         p->sysvinit_path = p->sysvrcnd_path = NULL;
 346 #endif
 347 }