src/shared/path-lookup.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2010 Lennart Poettering
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <errno.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24
  25 #include "alloc-util.h"
  26 #include "fileio.h"
  27 #include "fs-util.h"
  28 #include "install.h"
  29 #include "log.h"
  30 #include "macro.h"
  31 #include "mkdir.h"
  32 #include "path-lookup.h"
  33 #include "path-util.h"
  34 #include "rm-rf.h"
  35 #include "stat-util.h"
  36 #include "string-util.h"
  37 #include "strv.h"
  38 #include "user-util.h"
  39 #include "util.h"
  40
  41 static int user_runtime_dir(char **ret, const char *suffix) {
  42         const char *e;
  43         char *j;
  44
  45         assert(ret);
  46         assert(suffix);
  47
  48         e = getenv("XDG_RUNTIME_DIR");
  49         if (!e)
  50                 return -ENXIO;
  51
  52         j = strappend(e, suffix);
  53         if (!j)
  54                 return -ENOMEM;
  55
  56         *ret = j;
  57         return 0;
  58 }
  59
  60 static int user_config_dir(char **ret, const char *suffix) {
  61         const char *e;
  62         char *j;
  63         int r;
  64
  65         assert(ret);
  66
  67         e = getenv("XDG_CONFIG_HOME");
  68         if (e)
  69                 j = strappend(e, suffix);
  70         else {
  71                 _cleanup_free_ char *home = NULL;
  72
  73                 r = get_home_dir(&home);
  74                 if (r < 0)
  75                         return r;
  76
  77                 j = strjoin(home, "/.config", suffix);
  78         }
  79
  80         if (!j)
  81                 return -ENOMEM;
  82
  83         *ret = j;
  84         return 0;
  85 }
  86
  87 static int user_data_dir(char **ret, const char *suffix) {
  88         const char *e;
  89         char *j;
  90         int r;
  91
  92         assert(ret);
  93         assert(suffix);
  94
  95         /* We don't treat /etc/xdg/systemd here as the spec
  96          * suggests because we assume that is a link to
  97          * /etc/systemd/ anyway. */
  98
  99         e = getenv("XDG_DATA_HOME");
 100         if (e)
 101                 j = strappend(e, suffix);
 102         else {
 103                 _cleanup_free_ char *home = NULL;
 104
 105                 r = get_home_dir(&home);
 106                 if (r < 0)
 107                         return r;
 108
 109                 j = strjoin(home, "/.local/share", suffix);
 110         }
 111         if (!j)
 112                 return -ENOMEM;
 113
 114         *ret = j;
 115         return 1;
 116 }
 117
 118 static char** user_dirs(
 119                 const char *persistent_config,
 120                 const char *runtime_config,
 121                 const char *generator,
 122                 const char *generator_early,
 123                 const char *generator_late,
 124                 const char *transient,
 125                 const char *persistent_control,
 126                 const char *runtime_control) {
 127
 128         const char * const config_unit_paths[] = {
 129                 USER_CONFIG_UNIT_PATH,
 130                 "/etc/systemd/user",
 131                 NULL
 132         };
 133
 134         const char * const data_unit_paths[] = {
 135                 "/usr/local/lib/systemd/user",
 136                 "/usr/local/share/systemd/user",
 137                 USER_DATA_UNIT_PATH,
 138                 "/usr/lib/systemd/user",
 139                 "/usr/share/systemd/user",
 140                 NULL
 141         };
 142
 143         _cleanup_strv_free_ char **config_dirs = NULL, **data_dirs = NULL;
 144         _cleanup_free_ char *data_home = NULL;
 145         _cleanup_strv_free_ char **res = NULL;
 146         const char *e;
 147         char **tmp;
 148         int r;
 149
 150         /* Implement the mechanisms defined in
 151          *
 152          * http://standards.freedesktop.org/basedir-spec/basedir-spec-0.6.html
 153          *
 154          * We look in both the config and the data dirs because we
 155          * want to encourage that distributors ship their unit files
 156          * as data, and allow overriding as configuration.
 157          */
 158
 159         e = getenv("XDG_CONFIG_DIRS");
 160         if (e) {
 161                 config_dirs = strv_split(e, ":");
 162                 if (!config_dirs)
 163                         return NULL;
 164         }
 165
 166         r = user_data_dir(&data_home, "/systemd/user");
 167         if (r < 0 && r != -ENXIO)
 168                 return NULL;
 169
 170         e = getenv("XDG_DATA_DIRS");
 171         if (e)
 172                 data_dirs = strv_split(e, ":");
 173         else
 174                 data_dirs = strv_new("/usr/local/share",
 175                                      "/usr/share",
 176                                      NULL);
 177         if (!data_dirs)
 178                 return NULL;
 179
 180         /* Now merge everything we found. */
 181         if (strv_extend(&res, persistent_control) < 0)
 182                 return NULL;
 183
 184         if (strv_extend(&res, runtime_control) < 0)
 185                 return NULL;
 186
 187         if (strv_extend(&res, transient) < 0)
 188                 return NULL;
 189
 190         if (strv_extend(&res, generator_early) < 0)
 191                 return NULL;
 192
 193         if (strv_extend_strv_concat(&res, config_dirs, "/systemd/user") < 0)
 194                 return NULL;
 195
 196         if (strv_extend(&res, persistent_config) < 0)
 197                 return NULL;
 198
 199         if (strv_extend_strv(&res, (char**) config_unit_paths, false) < 0)
 200                 return NULL;
 201
 202         if (strv_extend(&res, runtime_config) < 0)
 203                 return NULL;
 204
 205         if (strv_extend(&res, generator) < 0)
 206                 return NULL;
 207
 208         if (strv_extend(&res, data_home) < 0)
 209                 return NULL;
 210
 211         if (strv_extend_strv_concat(&res, data_dirs, "/systemd/user") < 0)
 212                 return NULL;
 213
 214         if (strv_extend_strv(&res, (char**) data_unit_paths, false) < 0)
 215                 return NULL;
 216
 217         if (strv_extend(&res, generator_late) < 0)
 218                 return NULL;
 219
 220         if (path_strv_make_absolute_cwd(res) < 0)
 221                 return NULL;
 222
 223         tmp = res;
 224         res = NULL;
 225
 226         return tmp;
 227 }
 228
 229 static int acquire_generator_dirs(
 230                 UnitFileScope scope,
 231                 const char *tempdir,
 232                 char **generator,
 233                 char **generator_early,
 234                 char **generator_late) {
 235
 236         _cleanup_(rmdir_and_freep) char *t = NULL;
 237         _cleanup_free_ char *x = NULL, *y = NULL, *z = NULL;
 238         const char *prefix;
 239
 240         assert(generator);
 241         assert(generator_early);
 242         assert(generator_late);
 243         assert(IN_SET(scope, UNIT_FILE_SYSTEM, UNIT_FILE_USER, UNIT_FILE_GLOBAL));
 244
 245         if (scope == UNIT_FILE_GLOBAL)
 246                 return -EOPNOTSUPP;
 247
 248         if (tempdir)
 249                 prefix = tempdir;
 250
 251         else if (scope == UNIT_FILE_SYSTEM)
 252                 prefix = "/run/systemd";
 253
 254         else if (scope == UNIT_FILE_USER) {
 255                 const char *e;
 256
 257                 e = getenv("XDG_RUNTIME_DIR");
 258                 if (!e)
 259                         return -ENXIO;
 260
 261                 prefix = strjoina(e, "/systemd");
 262         }
 263
 264         x = strappend(prefix, "/generator");
 265         if (!x)
 266                 return -ENOMEM;
 267
 268         y = strappend(prefix, "/generator.early");
 269         if (!y)
 270                 return -ENOMEM;
 271
 272         z = strappend(prefix, "/generator.late");
 273         if (!z)
 274                 return -ENOMEM;
 275
 276         *generator = x;
 277         *generator_early = y;
 278         *generator_late = z;
 279
 280         x = y = z = NULL;
 281         return 0;
 282 }
 283
 284 static int acquire_transient_dir(
 285                 UnitFileScope scope,
 286                 const char *tempdir,
 287                 char **ret) {
 288
 289         char *transient;
 290
 291         assert(ret);
 292         assert(IN_SET(scope, UNIT_FILE_SYSTEM, UNIT_FILE_USER, UNIT_FILE_GLOBAL));
 293
 294         if (scope == UNIT_FILE_GLOBAL)
 295                 return -EOPNOTSUPP;
 296
 297         if (tempdir)
 298                 transient = strjoin(tempdir, "/transient");
 299         else if (scope == UNIT_FILE_SYSTEM)
 300                 transient = strdup("/run/systemd/transient");
 301         else
 302                 return user_runtime_dir(ret, "/systemd/transient");
 303
 304         if (!transient)
 305                 return -ENOMEM;
 306         *ret = transient;
 307         return 0;
 308 }
 309
 310 static int acquire_config_dirs(UnitFileScope scope, char **persistent, char **runtime) {
 311         _cleanup_free_ char *a = NULL, *b = NULL;
 312         int r;
 313
 314         assert(persistent);
 315         assert(runtime);
 316
 317         switch (scope) {
 318
 319         case UNIT_FILE_SYSTEM:
 320                 a = strdup(SYSTEM_CONFIG_UNIT_PATH);
 321                 b = strdup("/run/systemd/system");
 322                 break;
 323
 324         case UNIT_FILE_GLOBAL:
 325                 a = strdup(USER_CONFIG_UNIT_PATH);
 326                 b = strdup("/run/systemd/user");
 327                 break;
 328
 329         case UNIT_FILE_USER:
 330                 r = user_config_dir(&a, "/systemd/user");
 331                 if (r < 0 && r != -ENXIO)
 332                         return r;
 333
 334                 r = user_runtime_dir(runtime, "/systemd/user");
 335                 if (r < 0) {
 336                         if (r != -ENXIO)
 337                                 return r;
 338
 339                         /* If XDG_RUNTIME_DIR is not set, don't consider that fatal, simply initialize the runtime
 340                          * directory to NULL */
 341                         *runtime = NULL;
 342                 }
 343
 344                 *persistent = a;
 345                 a = NULL;
 346
 347                 return 0;
 348
 349         default:
 350                 assert_not_reached("Hmm, unexpected scope value.");
 351         }
 352
 353         if (!a || !b)
 354                 return -ENOMEM;
 355
 356         *persistent = a;
 357         *runtime = b;
 358         a = b = NULL;
 359
 360         return 0;
 361 }
 362
 363 static int acquire_control_dirs(UnitFileScope scope, char **persistent, char **runtime) {
 364         _cleanup_free_ char *a = NULL;
 365         int r;
 366
 367         assert(persistent);
 368         assert(runtime);
 369
 370         switch (scope) {
 371
 372         case UNIT_FILE_SYSTEM:  {
 373                 _cleanup_free_ char *b = NULL;
 374
 375                 a = strdup("/etc/systemd/system.control");
 376                 if (!a)
 377                         return -ENOMEM;
 378
 379                 b = strdup("/run/systemd/system.control");
 380                 if (!b)
 381                         return -ENOMEM;
 382
 383                 *runtime = b;
 384                 b = NULL;
 385
 386                 break;
 387         }
 388
 389         case UNIT_FILE_USER:
 390                 r = user_config_dir(&a, "/systemd/system.control");
 391                 if (r < 0 && r != -ENXIO)
 392                         return r;
 393
 394                 r = user_runtime_dir(runtime, "/systemd/system.control");
 395                 if (r < 0) {
 396                         if (r != -ENXIO)
 397                                 return r;
 398
 399                         /* If XDG_RUNTIME_DIR is not set, don't consider this fatal, simply initialize the directory to
 400                          * NULL */
 401                         *runtime = NULL;
 402                 }
 403
 404                 break;
 405
 406         case UNIT_FILE_GLOBAL:
 407                 return -EOPNOTSUPP;
 408
 409         default:
 410                 assert_not_reached("Hmm, unexpected scope value.");
 411         }
 412
 413         *persistent = a;
 414         a = NULL;
 415
 416         return 0;
 417 }
 418
 419 static int patch_root_prefix(char **p, const char *root_dir) {
 420         char *c;
 421
 422         assert(p);
 423
 424         if (!*p)
 425                 return 0;
 426
 427         c = prefix_root(root_dir, *p);
 428         if (!c)
 429                 return -ENOMEM;
 430
 431         free(*p);
 432         *p = c;
 433
 434         return 0;
 435 }
 436
 437 static int patch_root_prefix_strv(char **l, const char *root_dir) {
 438         char **i;
 439         int r;
 440
 441         if (!root_dir)
 442                 return 0;
 443
 444         STRV_FOREACH(i, l) {
 445                 r = patch_root_prefix(i, root_dir);
 446                 if (r < 0)
 447                         return r;
 448         }
 449
 450         return 0;
 451 }
 452
 453 int lookup_paths_init(
 454                 LookupPaths *p,
 455                 UnitFileScope scope,
 456                 LookupPathsFlags flags,
 457                 const char *root_dir) {
 458
 459         _cleanup_(rmdir_and_freep) char *tempdir = NULL;
 460         _cleanup_free_ char
 461                 *root = NULL,
 462                 *persistent_config = NULL, *runtime_config = NULL,
 463                 *generator = NULL, *generator_early = NULL, *generator_late = NULL,
 464                 *transient = NULL,
 465                 *persistent_control = NULL, *runtime_control = NULL;
 466         bool append = false; /* Add items from SYSTEMD_UNIT_PATH before normal directories */
 467         _cleanup_strv_free_ char **paths = NULL;
 468         const char *e;
 469         int r;
 470
 471         assert(p);
 472         assert(scope >= 0);
 473         assert(scope < _UNIT_FILE_SCOPE_MAX);
 474
 475         if (!isempty(root_dir) && !path_equal(root_dir, "/")) {
 476                 if (scope == UNIT_FILE_USER)
 477                         return -EINVAL;
 478
 479                 r = is_dir(root_dir, true);
 480                 if (r < 0)
 481                         return r;
 482                 if (r == 0)
 483                         return -ENOTDIR;
 484
 485                 root = strdup(root_dir);
 486                 if (!root)
 487                         return -ENOMEM;
 488         }
 489
 490         if (flags & LOOKUP_PATHS_TEMPORARY_GENERATED) {
 491                 r = mkdtemp_malloc("/tmp/systemd-temporary-XXXXXX", &tempdir);
 492                 if (r < 0)
 493                         return log_error_errno(r, "Failed to create temporary directory: %m");
 494         }
 495
 496         /* Note: when XDG_RUNTIME_DIR is not set this will not return -ENXIO, but simply set runtime_config to NULL */
 497         r = acquire_config_dirs(scope, &persistent_config, &runtime_config);
 498         if (r < 0)
 499                 return r;
 500
 501         if ((flags & LOOKUP_PATHS_EXCLUDE_GENERATED) == 0) {
 502                 /* Note: if XDG_RUNTIME_DIR is not set, this will fail completely with ENXIO */
 503                 r = acquire_generator_dirs(scope, tempdir,
 504                                            &generator, &generator_early, &generator_late);
 505                 if (r < 0 && r != -EOPNOTSUPP && r != -ENXIO)
 506                         return r;
 507         }
 508
 509         /* Note: if XDG_RUNTIME_DIR is not set, this will fail completely with ENXIO */
 510         r = acquire_transient_dir(scope, tempdir, &transient);
 511         if (r < 0 && r != -EOPNOTSUPP && r != -ENXIO)
 512                 return r;
 513
 514         /* Note: when XDG_RUNTIME_DIR is not set this will not return -ENXIO, but simply set runtime_control to NULL */
 515         r = acquire_control_dirs(scope, &persistent_control, &runtime_control);
 516         if (r < 0 && r != -EOPNOTSUPP)
 517                 return r;
 518
 519         /* First priority is whatever has been passed to us via env vars */
 520         e = getenv("SYSTEMD_UNIT_PATH");
 521         if (e) {
 522                 const char *k;
 523
 524                 k = endswith(e, ":");
 525                 if (k) {
 526                         e = strndupa(e, k - e);
 527                         append = true;
 528                 }
 529
 530                 /* FIXME: empty components in other places should be rejected. */
 531
 532                 r = path_split_and_make_absolute(e, &paths);
 533                 if (r < 0)
 534                         return r;
 535         }
 536
 537         if (!paths || append) {
 538                 /* Let's figure something out. */
 539
 540                 _cleanup_strv_free_ char **add = NULL;
 541
 542                 /* For the user units we include share/ in the search
 543                  * path in order to comply with the XDG basedir spec.
 544                  * For the system stuff we avoid such nonsense. OTOH
 545                  * we include /lib in the search path for the system
 546                  * stuff but avoid it for user stuff. */
 547
 548                 switch (scope) {
 549
 550                 case UNIT_FILE_SYSTEM:
 551                         add = strv_new(
 552                                         /* If you modify this you also want to modify
 553                                          * systemdsystemunitpath= in systemd.pc.in! */
 554                                         STRV_IFNOTNULL(persistent_control),
 555                                         STRV_IFNOTNULL(runtime_control),
 556                                         STRV_IFNOTNULL(transient),
 557                                         STRV_IFNOTNULL(generator_early),
 558                                         persistent_config,
 559                                         SYSTEM_CONFIG_UNIT_PATH,
 560                                         "/etc/systemd/system",
 561                                         runtime_config,
 562                                         "/run/systemd/system",
 563                                         STRV_IFNOTNULL(generator),
 564                                         "/usr/local/lib/systemd/system",
 565                                         SYSTEM_DATA_UNIT_PATH,
 566                                         "/usr/lib/systemd/system",
 567 #ifdef HAVE_SPLIT_USR
 568                                         "/lib/systemd/system",
 569 #endif
 570                                         STRV_IFNOTNULL(generator_late),
 571                                         NULL);
 572                         break;
 573
 574                 case UNIT_FILE_GLOBAL:
 575                         add = strv_new(
 576                                         /* If you modify this you also want to modify
 577                                          * systemduserunitpath= in systemd.pc.in, and
 578                                          * the arrays in user_dirs() above! */
 579                                         STRV_IFNOTNULL(persistent_control),
 580                                         STRV_IFNOTNULL(runtime_control),
 581                                         STRV_IFNOTNULL(transient),
 582                                         STRV_IFNOTNULL(generator_early),
 583                                         persistent_config,
 584                                         USER_CONFIG_UNIT_PATH,
 585                                         "/etc/systemd/user",
 586                                         runtime_config,
 587                                         "/run/systemd/user",
 588                                         STRV_IFNOTNULL(generator),
 589                                         "/usr/local/lib/systemd/user",
 590                                         "/usr/local/share/systemd/user",
 591                                         USER_DATA_UNIT_PATH,
 592                                         "/usr/lib/systemd/user",
 593                                         "/usr/share/systemd/user",
 594                                         STRV_IFNOTNULL(generator_late),
 595                                         NULL);
 596                         break;
 597
 598                 case UNIT_FILE_USER:
 599                         add = user_dirs(persistent_config, runtime_config,
 600                                         generator, generator_early, generator_late,
 601                                         transient,
 602                                         persistent_config, runtime_control);
 603                         break;
 604
 605                 default:
 606                         assert_not_reached("Hmm, unexpected scope?");
 607                 }
 608
 609                 if (!add)
 610                         return -ENOMEM;
 611
 612                 if (paths) {
 613                         r = strv_extend_strv(&paths, add, true);
 614                         if (r < 0)
 615                                 return r;
 616                 } else {
 617                         /* Small optimization: if paths is NULL (and it usually is), we can simply assign 'add' to it,
 618                          * and don't have to copy anything */
 619                         paths = add;
 620                         add = NULL;
 621                 }
 622         }
 623
 624         r = patch_root_prefix(&persistent_config, root);
 625         if (r < 0)
 626                 return r;
 627         r = patch_root_prefix(&runtime_config, root);
 628         if (r < 0)
 629                 return r;
 630
 631         r = patch_root_prefix(&generator, root);
 632         if (r < 0)
 633                 return r;
 634         r = patch_root_prefix(&generator_early, root);
 635         if (r < 0)
 636                 return r;
 637         r = patch_root_prefix(&generator_late, root);
 638         if (r < 0)
 639                 return r;
 640
 641         r = patch_root_prefix(&transient, root);
 642         if (r < 0)
 643                 return r;
 644
 645         r = patch_root_prefix(&persistent_control, root);
 646         if (r < 0)
 647                 return r;
 648
 649         r = patch_root_prefix(&runtime_control, root);
 650         if (r < 0)
 651                 return r;
 652
 653         r = patch_root_prefix_strv(paths, root);
 654         if (r < 0)
 655                 return -ENOMEM;
 656
 657         p->search_path = strv_uniq(paths);
 658         paths = NULL;
 659
 660         p->persistent_config = persistent_config;
 661         p->runtime_config = runtime_config;
 662         persistent_config = runtime_config = NULL;
 663
 664         p->generator = generator;
 665         p->generator_early = generator_early;
 666         p->generator_late = generator_late;
 667         generator = generator_early = generator_late = NULL;
 668
 669         p->transient = transient;
 670         transient = NULL;
 671
 672         p->persistent_control = persistent_control;
 673         p->runtime_control = runtime_control;
 674         persistent_control = runtime_control = NULL;
 675
 676         p->root_dir = root;
 677         root = NULL;
 678
 679         p->temporary_dir = tempdir;
 680         tempdir = NULL;
 681
 682         return 0;
 683 }
 684
 685 void lookup_paths_free(LookupPaths *p) {
 686         if (!p)
 687                 return;
 688
 689         p->search_path = strv_free(p->search_path);
 690
 691         p->persistent_config = mfree(p->persistent_config);
 692         p->runtime_config = mfree(p->runtime_config);
 693
 694         p->generator = mfree(p->generator);
 695         p->generator_early = mfree(p->generator_early);
 696         p->generator_late = mfree(p->generator_late);
 697
 698         p->transient = mfree(p->transient);
 699
 700         p->persistent_control = mfree(p->persistent_control);
 701         p->runtime_control = mfree(p->runtime_control);
 702
 703         p->root_dir = mfree(p->root_dir);
 704 }
 705
 706 int lookup_paths_reduce(LookupPaths *p) {
 707         _cleanup_free_ struct stat *stats = NULL;
 708         size_t n_stats = 0, allocated = 0;
 709         unsigned c = 0;
 710         int r;
 711
 712         assert(p);
 713
 714         /* Drop duplicates and non-existing directories from the search path. We figure out whether two directories are
 715          * the same by comparing their device and inode numbers. Note one special tweak: when we have a root path set,
 716          * we do not follow symlinks when retrieving them, because the kernel wouldn't take the root prefix into
 717          * account when following symlinks. When we have no root path set this restriction does not apply however. */
 718
 719         if (!p->search_path)
 720                 return 0;
 721
 722         while (p->search_path[c]) {
 723                 struct stat st;
 724                 unsigned k;
 725
 726                 if (p->root_dir)
 727                         r = lstat(p->search_path[c], &st);
 728                 else
 729                         r = stat(p->search_path[c], &st);
 730                 if (r < 0) {
 731                         if (errno == ENOENT)
 732                                 goto remove_item;
 733
 734                         /* If something we don't grok happened, let's better leave it in. */
 735                         log_debug_errno(errno, "Failed to stat %s: %m", p->search_path[c]);
 736                         c++;
 737                         continue;
 738                 }
 739
 740                 for (k = 0; k < n_stats; k++) {
 741                         if (stats[k].st_dev == st.st_dev &&
 742                             stats[k].st_ino == st.st_ino)
 743                                 break;
 744                 }
 745
 746                 if (k < n_stats) /* Is there already an entry with the same device/inode? */
 747                         goto remove_item;
 748
 749                 if (!GREEDY_REALLOC(stats, allocated, n_stats+1))
 750                         return -ENOMEM;
 751
 752                 stats[n_stats++] = st;
 753                 c++;
 754                 continue;
 755
 756         remove_item:
 757                 free(p->search_path[c]);
 758                 memmove(p->search_path + c,
 759                         p->search_path + c + 1,
 760                         (strv_length(p->search_path + c + 1) + 1) * sizeof(char*));
 761         }
 762
 763         if (strv_isempty(p->search_path)) {
 764                 log_debug("Ignoring unit files.");
 765                 p->search_path = strv_free(p->search_path);
 766         } else {
 767                 _cleanup_free_ char *t;
 768
 769                 t = strv_join(p->search_path, "\n\t");
 770                 if (!t)
 771                         return -ENOMEM;
 772
 773                 log_debug("Looking for unit files in (higher priority first):\n\t%s", t);
 774         }
 775
 776         return 0;
 777 }
 778
 779 int lookup_paths_mkdir_generator(LookupPaths *p) {
 780         int r, q;
 781
 782         assert(p);
 783
 784         if (!p->generator || !p->generator_early || !p->generator_late)
 785                 return -EINVAL;
 786
 787         r = mkdir_p_label(p->generator, 0755);
 788
 789         q = mkdir_p_label(p->generator_early, 0755);
 790         if (q < 0 && r >= 0)
 791                 r = q;
 792
 793         q = mkdir_p_label(p->generator_late, 0755);
 794         if (q < 0 && r >= 0)
 795                 r = q;
 796
 797         return r;
 798 }
 799
 800 void lookup_paths_trim_generator(LookupPaths *p) {
 801         assert(p);
 802
 803         /* Trim empty dirs */
 804
 805         if (p->generator)
 806                 (void) rmdir(p->generator);
 807         if (p->generator_early)
 808                 (void) rmdir(p->generator_early);
 809         if (p->generator_late)
 810                 (void) rmdir(p->generator_late);
 811 }
 812
 813 void lookup_paths_flush_generator(LookupPaths *p) {
 814         assert(p);
 815
 816         /* Flush the generated unit files in full */
 817
 818         if (p->generator)
 819                 (void) rm_rf(p->generator, REMOVE_ROOT);
 820         if (p->generator_early)
 821                 (void) rm_rf(p->generator_early, REMOVE_ROOT);
 822         if (p->generator_late)
 823                 (void) rm_rf(p->generator_late, REMOVE_ROOT);
 824
 825         if (p->temporary_dir)
 826                 (void) rm_rf(p->temporary_dir, REMOVE_ROOT);
 827 }
 828
 829 char **generator_binary_paths(UnitFileScope scope) {
 830
 831         switch (scope) {
 832
 833         case UNIT_FILE_SYSTEM:
 834                 return strv_new("/run/systemd/system-generators",
 835                                 "/etc/systemd/system-generators",
 836                                 "/usr/local/lib/systemd/system-generators",
 837                                 SYSTEM_GENERATOR_PATH,
 838                                 NULL);
 839
 840         case UNIT_FILE_GLOBAL:
 841         case UNIT_FILE_USER:
 842                 return strv_new("/run/systemd/user-generators",
 843                                 "/etc/systemd/user-generators",
 844                                 "/usr/local/lib/systemd/user-generators",
 845                                 USER_GENERATOR_PATH,
 846                                 NULL);
 847
 848         default:
 849                 assert_not_reached("Hmm, unexpected scope.");
 850         }
 851 }