src/shared/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 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 <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 "mkdir.h"
  30 #include "strv.h"
  31 #include "path-util.h"
  32 #include "path-lookup.h"
  33
  34 int user_config_home(char **config_home) {
  35         const char *e;
  36
  37         if ((e = getenv("XDG_CONFIG_HOME"))) {
  38                 if (asprintf(config_home, "%s/systemd/user", e) < 0)
  39                         return -ENOMEM;
  40
  41                 return 1;
  42         } else {
  43                 const char *home;
  44
  45                 if ((home = getenv("HOME"))) {
  46                         if (asprintf(config_home, "%s/.config/systemd/user", home) < 0)
  47                                 return -ENOMEM;
  48
  49                         return 1;
  50                 }
  51         }
  52
  53         return 0;
  54 }
  55
  56 static char** user_dirs(void) {
  57         const char * const config_unit_paths[] = {
  58                 USER_CONFIG_UNIT_PATH,
  59                 "/etc/systemd/user",
  60                 "/run/systemd/user",
  61                 NULL
  62         };
  63
  64         const char * const data_unit_paths[] = {
  65                 "/usr/local/lib/systemd/user",
  66                 "/usr/local/share/systemd/user",
  67                 USER_DATA_UNIT_PATH,
  68                 "/usr/lib/systemd/user",
  69                 "/usr/share/systemd/user",
  70                 NULL
  71         };
  72
  73         const char *home, *e;
  74         char *config_home = NULL, *data_home = NULL;
  75         char **config_dirs = NULL, **data_dirs = NULL;
  76         char **r = NULL, **t;
  77
  78         /* Implement the mechanisms defined in
  79          *
  80          * http://standards.freedesktop.org/basedir-spec/basedir-spec-0.6.html
  81          *
  82          * We look in both the config and the data dirs because we
  83          * want to encourage that distributors ship their unit files
  84          * as data, and allow overriding as configuration.
  85          */
  86
  87         if (user_config_home(&config_home) < 0)
  88                 goto fail;
  89
  90         home = getenv("HOME");
  91
  92         if ((e = getenv("XDG_CONFIG_DIRS")))
  93                 if (!(config_dirs = strv_split(e, ":")))
  94                         goto fail;
  95
  96         /* We don't treat /etc/xdg/systemd here as the spec
  97          * suggests because we assume that that is a link to
  98          * /etc/systemd/ anyway. */
  99
 100         if ((e = getenv("XDG_DATA_HOME"))) {
 101                 if (asprintf(&data_home, "%s/systemd/user", e) < 0)
 102                         goto fail;
 103
 104         } else if (home) {
 105                 if (asprintf(&data_home, "%s/.local/share/systemd/user", home) < 0)
 106                         goto fail;
 107
 108                 /* There is really no need for two unit dirs in $HOME,
 109                  * except to be fully compliant with the XDG spec. We
 110                  * now try to link the two dirs, so that we can
 111                  * minimize disk seeks a little. Further down we'll
 112                  * then filter out this link, if it is actually is
 113                  * one. */
 114
 115                 mkdir_parents(data_home, 0777);
 116                 (void) symlink("../../../.config/systemd/user", data_home);
 117         }
 118
 119         if ((e = getenv("XDG_DATA_DIRS")))
 120                 data_dirs = strv_split(e, ":");
 121         else
 122                 data_dirs = strv_new("/usr/local/share",
 123                                      "/usr/share",
 124                                      NULL);
 125
 126         if (!data_dirs)
 127                 goto fail;
 128
 129         /* Now merge everything we found. */
 130         if (config_home) {
 131                 if (!(t = strv_append(r, config_home)))
 132                         goto fail;
 133                 strv_free(r);
 134                 r = t;
 135         }
 136
 137         if (!strv_isempty(config_dirs)) {
 138                 if (!(t = strv_merge_concat(r, config_dirs, "/systemd/user")))
 139                         goto finish;
 140                 strv_free(r);
 141                 r = t;
 142         }
 143
 144         if (!(t = strv_merge(r, (char**) config_unit_paths)))
 145                 goto fail;
 146         strv_free(r);
 147         r = t;
 148
 149         if (data_home) {
 150                 if (!(t = strv_append(r, data_home)))
 151                         goto fail;
 152                 strv_free(r);
 153                 r = t;
 154         }
 155
 156         if (!strv_isempty(data_dirs)) {
 157                 if (!(t = strv_merge_concat(r, data_dirs, "/systemd/user")))
 158                         goto fail;
 159                 strv_free(r);
 160                 r = t;
 161         }
 162
 163         if (!(t = strv_merge(r, (char**) data_unit_paths)))
 164                 goto fail;
 165         strv_free(r);
 166         r = t;
 167
 168         if (!path_strv_make_absolute_cwd(r))
 169             goto fail;
 170
 171 finish:
 172         free(config_home);
 173         strv_free(config_dirs);
 174         free(data_home);
 175         strv_free(data_dirs);
 176
 177         return r;
 178
 179 fail:
 180         strv_free(r);
 181         r = NULL;
 182         goto finish;
 183 }
 184
 185 int lookup_paths_init(LookupPaths *p, ManagerRunningAs running_as, bool personal) {
 186         const char *e;
 187         char *t;
 188
 189         assert(p);
 190
 191         /* First priority is whatever has been passed to us via env
 192          * vars */
 193         if ((e = getenv("SYSTEMD_UNIT_PATH")))
 194                 if (!(p->unit_path = path_split_and_make_absolute(e)))
 195                         return -ENOMEM;
 196
 197         if (strv_isempty(p->unit_path)) {
 198
 199                 /* Nothing is set, so let's figure something out. */
 200                 strv_free(p->unit_path);
 201
 202                 if (running_as == MANAGER_USER) {
 203
 204                         if (personal)
 205                                 p->unit_path = user_dirs();
 206                         else
 207                                 p->unit_path = strv_new(
 208                                                 /* If you modify this you also want to modify
 209                                                  * systemduserunitpath= in systemd.pc.in, and
 210                                                  * the arrays in user_dirs() above! */
 211                                                 USER_CONFIG_UNIT_PATH,
 212                                                 "/etc/systemd/user",
 213                                                 "/run/systemd/user",
 214                                                 "/usr/local/lib/systemd/user",
 215                                                 "/usr/local/share/systemd/user",
 216                                                 USER_DATA_UNIT_PATH,
 217                                                 "/usr/lib/systemd/user",
 218                                                 "/usr/share/systemd/user",
 219                                                 NULL);
 220
 221                         if (!p->unit_path)
 222                                 return -ENOMEM;
 223
 224                 } else
 225                         if (!(p->unit_path = strv_new(
 226                                               /* If you modify this you also want to modify
 227                                                * systemdsystemunitpath= in systemd.pc.in! */
 228                                               SYSTEM_CONFIG_UNIT_PATH,
 229                                               "/etc/systemd/system",
 230                                               "/run/systemd/system",
 231                                               "/usr/local/lib/systemd/system",
 232                                               SYSTEM_DATA_UNIT_PATH,
 233                                               "/usr/lib/systemd/system",
 234 #ifdef HAVE_SPLIT_USR
 235                                               "/lib/systemd/system",
 236 #endif
 237                                               NULL)))
 238                                 return -ENOMEM;
 239         }
 240
 241         if (p->unit_path)
 242                 if (!path_strv_canonicalize(p->unit_path))
 243                         return -ENOMEM;
 244
 245         strv_uniq(p->unit_path);
 246         path_strv_remove_empty(p->unit_path);
 247
 248         if (!strv_isempty(p->unit_path)) {
 249
 250                 if (!(t = strv_join(p->unit_path, "\n\t")))
 251                         return -ENOMEM;
 252                 log_debug("Looking for unit files in:\n\t%s", t);
 253                 free(t);
 254         } else {
 255                 log_debug("Ignoring unit files.");
 256                 strv_free(p->unit_path);
 257                 p->unit_path = NULL;
 258         }
 259
 260         if (running_as == MANAGER_SYSTEM) {
 261 #ifdef HAVE_SYSV_COMPAT
 262                 /* /etc/init.d/ compatibility does not matter to users */
 263
 264                 if ((e = getenv("SYSTEMD_SYSVINIT_PATH")))
 265                         if (!(p->sysvinit_path = path_split_and_make_absolute(e)))
 266                                 return -ENOMEM;
 267
 268                 if (strv_isempty(p->sysvinit_path)) {
 269                         strv_free(p->sysvinit_path);
 270
 271                         if (!(p->sysvinit_path = strv_new(
 272                                               SYSTEM_SYSVINIT_PATH,     /* /etc/init.d/ */
 273                                               NULL)))
 274                                 return -ENOMEM;
 275                 }
 276
 277                 if ((e = getenv("SYSTEMD_SYSVRCND_PATH")))
 278                         if (!(p->sysvrcnd_path = path_split_and_make_absolute(e)))
 279                                 return -ENOMEM;
 280
 281                 if (strv_isempty(p->sysvrcnd_path)) {
 282                         strv_free(p->sysvrcnd_path);
 283
 284                         if (!(p->sysvrcnd_path = strv_new(
 285                                               SYSTEM_SYSVRCND_PATH,     /* /etc/rcN.d/ */
 286                                               NULL)))
 287                                 return -ENOMEM;
 288                 }
 289
 290                 if (p->sysvinit_path)
 291                         if (!path_strv_canonicalize(p->sysvinit_path))
 292                                 return -ENOMEM;
 293
 294                 if (p->sysvrcnd_path)
 295                         if (!path_strv_canonicalize(p->sysvrcnd_path))
 296                                 return -ENOMEM;
 297
 298                 strv_uniq(p->sysvinit_path);
 299                 strv_uniq(p->sysvrcnd_path);
 300
 301                 path_strv_remove_empty(p->sysvinit_path);
 302                 path_strv_remove_empty(p->sysvrcnd_path);
 303
 304                 if (!strv_isempty(p->sysvinit_path)) {
 305
 306                         if (!(t = strv_join(p->sysvinit_path, "\n\t")))
 307                                 return -ENOMEM;
 308
 309                         log_debug("Looking for SysV init scripts in:\n\t%s", t);
 310                         free(t);
 311                 } else {
 312                         log_debug("Ignoring SysV init scripts.");
 313                         strv_free(p->sysvinit_path);
 314                         p->sysvinit_path = NULL;
 315                 }
 316
 317                 if (!strv_isempty(p->sysvrcnd_path)) {
 318
 319                         if (!(t = strv_join(p->sysvrcnd_path, "\n\t")))
 320                                 return -ENOMEM;
 321
 322                         log_debug("Looking for SysV rcN.d links in:\n\t%s", t);
 323                         free(t);
 324                 } else {
 325                         log_debug("Ignoring SysV rcN.d links.");
 326                         strv_free(p->sysvrcnd_path);
 327                         p->sysvrcnd_path = NULL;
 328                 }
 329 #else
 330                 log_debug("Disabled SysV init scripts and rcN.d links support");
 331 #endif
 332         }
 333
 334         return 0;
 335 }
 336
 337 void lookup_paths_free(LookupPaths *p) {
 338         assert(p);
 339
 340         strv_free(p->unit_path);
 341         p->unit_path = NULL;
 342
 343 #ifdef HAVE_SYSV_COMPAT
 344         strv_free(p->sysvinit_path);
 345         strv_free(p->sysvrcnd_path);
 346         p->sysvinit_path = p->sysvrcnd_path = NULL;
 347 #endif
 348 }