src/delta/delta.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <errno.h>
   4 #include <getopt.h>
   5 #include <sys/prctl.h>
   6 #include <unistd.h>
   7
   8 #include "alloc-util.h"
   9 #include "dirent-util.h"
  10 #include "fd-util.h"
  11 #include "fs-util.h"
  12 #include "hashmap.h"
  13 #include "locale-util.h"
  14 #include "log.h"
  15 #include "main-func.h"
  16 #include "nulstr-util.h"
  17 #include "pager.h"
  18 #include "parse-argument.h"
  19 #include "parse-util.h"
  20 #include "path-util.h"
  21 #include "pretty-print.h"
  22 #include "process-util.h"
  23 #include "signal-util.h"
  24 #include "stat-util.h"
  25 #include "string-util.h"
  26 #include "strv.h"
  27 #include "terminal-util.h"
  28
  29 static const char prefixes[] =
  30         "/etc\0"
  31         "/run\0"
  32         "/usr/local/lib\0"
  33         "/usr/local/share\0"
  34         "/usr/lib\0"
  35         "/usr/share\0"
  36 #if HAVE_SPLIT_USR
  37         "/lib\0"
  38 #endif
  39         ;
  40
  41 static const char suffixes[] =
  42         "sysctl.d\0"
  43         "tmpfiles.d\0"
  44         "modules-load.d\0"
  45         "binfmt.d\0"
  46         "systemd/system\0"
  47         "systemd/user\0"
  48         "systemd/system-preset\0"
  49         "systemd/user-preset\0"
  50         "udev/rules.d\0"
  51         "modprobe.d\0";
  52
  53 static const char have_dropins[] =
  54         "systemd/system\0"
  55         "systemd/user\0";
  56
  57 static PagerFlags arg_pager_flags = 0;
  58 static int arg_diff = -1;
  59
  60 static enum {
  61         SHOW_MASKED     = 1 << 0,
  62         SHOW_EQUIVALENT = 1 << 1,
  63         SHOW_REDIRECTED = 1 << 2,
  64         SHOW_OVERRIDDEN = 1 << 3,
  65         SHOW_UNCHANGED  = 1 << 4,
  66         SHOW_EXTENDED   = 1 << 5,
  67
  68         SHOW_DEFAULTS =
  69         (SHOW_MASKED | SHOW_EQUIVALENT | SHOW_REDIRECTED | SHOW_OVERRIDDEN | SHOW_EXTENDED)
  70 } arg_flags = 0;
  71
  72 static int equivalent(const char *a, const char *b) {
  73         _cleanup_free_ char *x = NULL, *y = NULL;
  74         int r;
  75
  76         r = chase_symlinks(a, NULL, CHASE_TRAIL_SLASH, &x, NULL);
  77         if (r < 0)
  78                 return r;
  79
  80         r = chase_symlinks(b, NULL, CHASE_TRAIL_SLASH, &y, NULL);
  81         if (r < 0)
  82                 return r;
  83
  84         return path_equal(x, y);
  85 }
  86
  87 static int notify_override_masked(const char *top, const char *bottom) {
  88         if (!(arg_flags & SHOW_MASKED))
  89                 return 0;
  90
  91         printf("%s%s%s     %s %s %s\n",
  92                ansi_highlight_red(), "[MASKED]", ansi_normal(),
  93                top, special_glyph(SPECIAL_GLYPH_ARROW), bottom);
  94         return 1;
  95 }
  96
  97 static int notify_override_equivalent(const char *top, const char *bottom) {
  98         if (!(arg_flags & SHOW_EQUIVALENT))
  99                 return 0;
 100
 101         printf("%s%s%s %s %s %s\n",
 102                ansi_highlight_green(), "[EQUIVALENT]", ansi_normal(),
 103                top, special_glyph(SPECIAL_GLYPH_ARROW), bottom);
 104         return 1;
 105 }
 106
 107 static int notify_override_redirected(const char *top, const char *bottom) {
 108         if (!(arg_flags & SHOW_REDIRECTED))
 109                 return 0;
 110
 111         printf("%s%s%s %s %s %s\n",
 112                ansi_highlight(), "[REDIRECTED]", ansi_normal(),
 113                top, special_glyph(SPECIAL_GLYPH_ARROW), bottom);
 114         return 1;
 115 }
 116
 117 static int notify_override_overridden(const char *top, const char *bottom) {
 118         if (!(arg_flags & SHOW_OVERRIDDEN))
 119                 return 0;
 120
 121         printf("%s%s%s %s %s %s\n",
 122                ansi_highlight(), "[OVERRIDDEN]", ansi_normal(),
 123                top, special_glyph(SPECIAL_GLYPH_ARROW), bottom);
 124         return 1;
 125 }
 126
 127 static int notify_override_extended(const char *top, const char *bottom) {
 128         if (!(arg_flags & SHOW_EXTENDED))
 129                return 0;
 130
 131         printf("%s%s%s   %s %s %s\n",
 132                ansi_highlight(), "[EXTENDED]", ansi_normal(),
 133                top, special_glyph(SPECIAL_GLYPH_ARROW), bottom);
 134         return 1;
 135 }
 136
 137 static int notify_override_unchanged(const char *f) {
 138         if (!(arg_flags & SHOW_UNCHANGED))
 139                 return 0;
 140
 141         printf("[UNCHANGED]  %s\n", f);
 142         return 1;
 143 }
 144
 145 static int found_override(const char *top, const char *bottom) {
 146         _cleanup_free_ char *dest = NULL;
 147         pid_t pid;
 148         int r;
 149
 150         assert(top);
 151         assert(bottom);
 152
 153         if (null_or_empty_path(top) > 0)
 154                 return notify_override_masked(top, bottom);
 155
 156         r = readlink_malloc(top, &dest);
 157         if (r >= 0) {
 158                 if (equivalent(dest, bottom) > 0)
 159                         return notify_override_equivalent(top, bottom);
 160                 else
 161                         return notify_override_redirected(top, bottom);
 162         }
 163
 164         r = notify_override_overridden(top, bottom);
 165         if (!arg_diff)
 166                 return r;
 167
 168         putchar('\n');
 169
 170         fflush(stdout);
 171
 172         r = safe_fork("(diff)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_CLOSE_ALL_FDS|FORK_RLIMIT_NOFILE_SAFE|FORK_LOG, &pid);
 173         if (r < 0)
 174                 return r;
 175         if (r == 0) {
 176                 execlp("diff", "diff", "-us", "--", bottom, top, NULL);
 177                 log_open();
 178                 log_error_errno(errno, "Failed to execute diff: %m");
 179                 _exit(EXIT_FAILURE);
 180         }
 181
 182         (void) wait_for_terminate_and_check("diff", pid, WAIT_LOG_ABNORMAL);
 183         putchar('\n');
 184
 185         return r;
 186 }
 187
 188 static int enumerate_dir_d(
 189                 OrderedHashmap *top,
 190                 OrderedHashmap *bottom,
 191                 OrderedHashmap *drops,
 192                 const char *toppath, const char *drop) {
 193
 194         _cleanup_free_ char *unit = NULL;
 195         _cleanup_free_ char *path = NULL;
 196         _cleanup_strv_free_ char **list = NULL;
 197         char **file;
 198         char *c;
 199         int r;
 200
 201         assert(!endswith(drop, "/"));
 202
 203         path = path_join(toppath, drop);
 204         if (!path)
 205                 return -ENOMEM;
 206
 207         log_debug("Looking at %s", path);
 208
 209         unit = strdup(drop);
 210         if (!unit)
 211                 return -ENOMEM;
 212
 213         c = strrchr(unit, '.');
 214         if (!c)
 215                 return -EINVAL;
 216         *c = 0;
 217
 218         r = get_files_in_directory(path, &list);
 219         if (r < 0)
 220                 return log_error_errno(r, "Failed to enumerate %s: %m", path);
 221
 222         strv_sort(list);
 223
 224         STRV_FOREACH(file, list) {
 225                 OrderedHashmap *h;
 226                 int k;
 227                 char *p;
 228                 char *d;
 229
 230                 if (!endswith(*file, ".conf"))
 231                         continue;
 232
 233                 p = path_join(path, *file);
 234                 if (!p)
 235                         return -ENOMEM;
 236                 d = p + strlen(toppath) + 1;
 237
 238                 log_debug("Adding at top: %s %s %s", d, special_glyph(SPECIAL_GLYPH_ARROW), p);
 239                 k = ordered_hashmap_put(top, d, p);
 240                 if (k >= 0) {
 241                         p = strdup(p);
 242                         if (!p)
 243                                 return -ENOMEM;
 244                         d = p + strlen(toppath) + 1;
 245                 } else if (k != -EEXIST) {
 246                         free(p);
 247                         return k;
 248                 }
 249
 250                 log_debug("Adding at bottom: %s %s %s", d, special_glyph(SPECIAL_GLYPH_ARROW), p);
 251                 free(ordered_hashmap_remove(bottom, d));
 252                 k = ordered_hashmap_put(bottom, d, p);
 253                 if (k < 0) {
 254                         free(p);
 255                         return k;
 256                 }
 257
 258                 h = ordered_hashmap_get(drops, unit);
 259                 if (!h) {
 260                         h = ordered_hashmap_new(&string_hash_ops);
 261                         if (!h)
 262                                 return -ENOMEM;
 263                         ordered_hashmap_put(drops, unit, h);
 264                         unit = strdup(unit);
 265                         if (!unit)
 266                                 return -ENOMEM;
 267                 }
 268
 269                 p = strdup(p);
 270                 if (!p)
 271                         return -ENOMEM;
 272
 273                 log_debug("Adding to drops: %s %s %s %s %s",
 274                           unit, special_glyph(SPECIAL_GLYPH_ARROW), basename(p), special_glyph(SPECIAL_GLYPH_ARROW), p);
 275                 k = ordered_hashmap_put(h, basename(p), p);
 276                 if (k < 0) {
 277                         free(p);
 278                         if (k != -EEXIST)
 279                                 return k;
 280                 }
 281         }
 282         return 0;
 283 }
 284
 285 static int enumerate_dir(
 286                 OrderedHashmap *top,
 287                 OrderedHashmap *bottom,
 288                 OrderedHashmap *drops,
 289                 const char *path, bool dropins) {
 290
 291         _cleanup_closedir_ DIR *d = NULL;
 292         struct dirent *de;
 293         _cleanup_strv_free_ char **files = NULL, **dirs = NULL;
 294         size_t n_files = 0, n_dirs = 0;
 295         char **t;
 296         int r;
 297
 298         assert(top);
 299         assert(bottom);
 300         assert(drops);
 301         assert(path);
 302
 303         log_debug("Looking at %s", path);
 304
 305         d = opendir(path);
 306         if (!d) {
 307                 if (errno == ENOENT)
 308                         return 0;
 309
 310                 return log_error_errno(errno, "Failed to open %s: %m", path);
 311         }
 312
 313         FOREACH_DIRENT_ALL(de, d, return -errno) {
 314                 if (dropins && de->d_type == DT_DIR && endswith(de->d_name, ".d")) {
 315                         if (!GREEDY_REALLOC0(dirs, n_dirs + 2))
 316                                 return -ENOMEM;
 317
 318                         dirs[n_dirs] = strdup(de->d_name);
 319                         if (!dirs[n_dirs])
 320                                 return -ENOMEM;
 321                         n_dirs ++;
 322                 }
 323
 324                 if (!dirent_is_file(de))
 325                         continue;
 326
 327                 if (!GREEDY_REALLOC0(files, n_files + 2))
 328                         return -ENOMEM;
 329
 330                 files[n_files] = strdup(de->d_name);
 331                 if (!files[n_files])
 332                         return -ENOMEM;
 333                 n_files ++;
 334         }
 335
 336         strv_sort(dirs);
 337         strv_sort(files);
 338
 339         STRV_FOREACH(t, dirs) {
 340                 r = enumerate_dir_d(top, bottom, drops, path, *t);
 341                 if (r < 0)
 342                         return r;
 343         }
 344
 345         STRV_FOREACH(t, files) {
 346                 _cleanup_free_ char *p = NULL;
 347
 348                 p = path_join(path, *t);
 349                 if (!p)
 350                         return -ENOMEM;
 351
 352                 log_debug("Adding at top: %s %s %s", basename(p), special_glyph(SPECIAL_GLYPH_ARROW), p);
 353                 r = ordered_hashmap_put(top, basename(p), p);
 354                 if (r >= 0) {
 355                         p = strdup(p);
 356                         if (!p)
 357                                 return -ENOMEM;
 358                 } else if (r != -EEXIST)
 359                         return r;
 360
 361                 log_debug("Adding at bottom: %s %s %s", basename(p), special_glyph(SPECIAL_GLYPH_ARROW), p);
 362                 free(ordered_hashmap_remove(bottom, basename(p)));
 363                 r = ordered_hashmap_put(bottom, basename(p), p);
 364                 if (r < 0)
 365                         return r;
 366                 p = NULL;
 367         }
 368
 369         return 0;
 370 }
 371
 372 static int should_skip_path(const char *prefix, const char *suffix) {
 373 #if HAVE_SPLIT_USR
 374         _cleanup_free_ char *target = NULL;
 375         const char *dirname, *p;
 376
 377         dirname = prefix_roota(prefix, suffix);
 378
 379         if (chase_symlinks(dirname, NULL, 0, &target, NULL) < 0)
 380                 return false;
 381
 382         NULSTR_FOREACH(p, prefixes) {
 383                 _cleanup_free_ char *tmp = NULL;
 384
 385                 if (path_startswith(dirname, p))
 386                         continue;
 387
 388                 tmp = path_join(p, suffix);
 389                 if (!tmp)
 390                         return -ENOMEM;
 391
 392                 if (path_equal(target, tmp)) {
 393                         log_debug("%s redirects to %s, skipping.", dirname, target);
 394                         return true;
 395                 }
 396         }
 397 #endif
 398         return false;
 399 }
 400
 401 static int process_suffix(const char *suffix, const char *onlyprefix) {
 402         const char *p;
 403         char *f, *key;
 404         OrderedHashmap *top, *bottom, *drops, *h;
 405         int r = 0, k, n_found = 0;
 406         bool dropins;
 407
 408         assert(suffix);
 409         assert(!startswith(suffix, "/"));
 410         assert(!strstr(suffix, "//"));
 411
 412         dropins = nulstr_contains(have_dropins, suffix);
 413
 414         top = ordered_hashmap_new(&string_hash_ops);
 415         bottom = ordered_hashmap_new(&string_hash_ops);
 416         drops = ordered_hashmap_new(&string_hash_ops);
 417         if (!top || !bottom || !drops) {
 418                 r = -ENOMEM;
 419                 goto finish;
 420         }
 421
 422         NULSTR_FOREACH(p, prefixes) {
 423                 _cleanup_free_ char *t = NULL;
 424
 425                 if (should_skip_path(p, suffix) > 0)
 426                         continue;
 427
 428                 t = path_join(p, suffix);
 429                 if (!t) {
 430                         r = -ENOMEM;
 431                         goto finish;
 432                 }
 433
 434                 k = enumerate_dir(top, bottom, drops, t, dropins);
 435                 if (r == 0)
 436                         r = k;
 437         }
 438
 439         ORDERED_HASHMAP_FOREACH_KEY(f, key, top) {
 440                 char *o;
 441
 442                 o = ordered_hashmap_get(bottom, key);
 443                 assert(o);
 444
 445                 if (!onlyprefix || startswith(o, onlyprefix)) {
 446                         if (path_equal(o, f)) {
 447                                 notify_override_unchanged(f);
 448                         } else {
 449                                 k = found_override(f, o);
 450                                 if (k < 0)
 451                                         r = k;
 452                                 else
 453                                         n_found += k;
 454                         }
 455                 }
 456
 457                 h = ordered_hashmap_get(drops, key);
 458                 if (h)
 459                         ORDERED_HASHMAP_FOREACH(o, h)
 460                                 if (!onlyprefix || startswith(o, onlyprefix))
 461                                         n_found += notify_override_extended(f, o);
 462         }
 463
 464 finish:
 465         ordered_hashmap_free_free(top);
 466         ordered_hashmap_free_free(bottom);
 467
 468         ORDERED_HASHMAP_FOREACH_KEY(h, key, drops) {
 469                 ordered_hashmap_free_free(ordered_hashmap_remove(drops, key));
 470                 ordered_hashmap_remove(drops, key);
 471                 free(key);
 472         }
 473         ordered_hashmap_free(drops);
 474
 475         return r < 0 ? r : n_found;
 476 }
 477
 478 static int process_suffixes(const char *onlyprefix) {
 479         const char *n;
 480         int n_found = 0, r;
 481
 482         NULSTR_FOREACH(n, suffixes) {
 483                 r = process_suffix(n, onlyprefix);
 484                 if (r < 0)
 485                         return r;
 486
 487                 n_found += r;
 488         }
 489
 490         return n_found;
 491 }
 492
 493 static int process_suffix_chop(const char *arg) {
 494         const char *p;
 495
 496         assert(arg);
 497
 498         if (!path_is_absolute(arg))
 499                 return process_suffix(arg, NULL);
 500
 501         /* Strip prefix from the suffix */
 502         NULSTR_FOREACH(p, prefixes) {
 503                 const char *suffix;
 504
 505                 suffix = startswith(arg, p);
 506                 if (suffix) {
 507                         suffix += strspn(suffix, "/");
 508                         if (*suffix)
 509                                 return process_suffix(suffix, p);
 510                         else
 511                                 return process_suffixes(arg);
 512                 }
 513         }
 514
 515         return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 516                                "Invalid suffix specification %s.", arg);
 517 }
 518
 519 static int help(void) {
 520         _cleanup_free_ char *link = NULL;
 521         int r;
 522
 523         r = terminal_urlify_man("systemd-delta", "1", &link);
 524         if (r < 0)
 525                 return log_oom();
 526
 527         printf("%s [OPTIONS...] [SUFFIX...]\n\n"
 528                "Find overridden configuration files.\n\n"
 529                "  -h --help           Show this help\n"
 530                "     --version        Show package version\n"
 531                "     --no-pager       Do not pipe output into a pager\n"
 532                "     --diff[=1|0]     Show a diff when overridden files differ\n"
 533                "  -t --type=LIST...   Only display a selected set of override types\n"
 534                "\nSee the %s for details.\n",
 535                program_invocation_short_name,
 536                link);
 537
 538         return 0;
 539 }
 540
 541 static int parse_flags(const char *flag_str, int flags) {
 542         for (;;) {
 543                 _cleanup_free_ char *word = NULL;
 544                 int r;
 545
 546                 r = extract_first_word(&flag_str, &word, ",", EXTRACT_DONT_COALESCE_SEPARATORS);
 547                 if (r < 0)
 548                         return r;
 549                 if (r == 0)
 550                         return flags;
 551
 552                 if (streq(word, "masked"))
 553                         flags |= SHOW_MASKED;
 554                 else if (streq(word, "equivalent"))
 555                         flags |= SHOW_EQUIVALENT;
 556                 else if (streq(word, "redirected"))
 557                         flags |= SHOW_REDIRECTED;
 558                 else if (streq(word, "overridden"))
 559                         flags |= SHOW_OVERRIDDEN;
 560                 else if (streq(word, "unchanged"))
 561                         flags |= SHOW_UNCHANGED;
 562                 else if (streq(word, "extended"))
 563                         flags |= SHOW_EXTENDED;
 564                 else if (streq(word, "default"))
 565                         flags |= SHOW_DEFAULTS;
 566                 else
 567                         return -EINVAL;
 568         }
 569 }
 570
 571 static int parse_argv(int argc, char *argv[]) {
 572
 573         enum {
 574                 ARG_NO_PAGER = 0x100,
 575                 ARG_DIFF,
 576                 ARG_VERSION
 577         };
 578
 579         static const struct option options[] = {
 580                 { "help",      no_argument,       NULL, 'h'          },
 581                 { "version",   no_argument,       NULL, ARG_VERSION  },
 582                 { "no-pager",  no_argument,       NULL, ARG_NO_PAGER },
 583                 { "diff",      optional_argument, NULL, ARG_DIFF     },
 584                 { "type",      required_argument, NULL, 't'          },
 585                 {}
 586         };
 587
 588         int c, r;
 589
 590         assert(argc >= 1);
 591         assert(argv);
 592
 593         while ((c = getopt_long(argc, argv, "ht:", options, NULL)) >= 0)
 594
 595                 switch (c) {
 596
 597                 case 'h':
 598                         return help();
 599
 600                 case ARG_VERSION:
 601                         return version();
 602
 603                 case ARG_NO_PAGER:
 604                         arg_pager_flags |= PAGER_DISABLE;
 605                         break;
 606
 607                 case 't': {
 608                         int f;
 609                         f = parse_flags(optarg, arg_flags);
 610                         if (f < 0)
 611                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 612                                                        "Failed to parse flags field.");
 613                         arg_flags = f;
 614                         break;
 615                 }
 616
 617                 case ARG_DIFF:
 618                         r = parse_boolean_argument("--diff", optarg, NULL);
 619                         if (r < 0)
 620                                 return r;
 621                         arg_diff = r;
 622                         break;
 623
 624                 case '?':
 625                         return -EINVAL;
 626
 627                 default:
 628                         assert_not_reached();
 629                 }
 630
 631         return 1;
 632 }
 633
 634 static int run(int argc, char *argv[]) {
 635         int r, k, n_found = 0;
 636
 637         log_setup();
 638
 639         r = parse_argv(argc, argv);
 640         if (r <= 0)
 641                 return r;
 642
 643         if (arg_flags == 0)
 644                 arg_flags = SHOW_DEFAULTS;
 645
 646         if (arg_diff < 0)
 647                 arg_diff = !!(arg_flags & SHOW_OVERRIDDEN);
 648         else if (arg_diff)
 649                 arg_flags |= SHOW_OVERRIDDEN;
 650
 651         (void) pager_open(arg_pager_flags);
 652
 653         if (optind < argc) {
 654                 int i;
 655
 656                 for (i = optind; i < argc; i++) {
 657                         path_simplify(argv[i]);
 658
 659                         k = process_suffix_chop(argv[i]);
 660                         if (k < 0)
 661                                 r = k;
 662                         else
 663                                 n_found += k;
 664                 }
 665
 666         } else {
 667                 k = process_suffixes(NULL);
 668                 if (k < 0)
 669                         r = k;
 670                 else
 671                         n_found += k;
 672         }
 673
 674         if (r >= 0)
 675                 printf("%s%i overridden configuration files found.\n", n_found ? "\n" : "", n_found);
 676         return r;
 677 }
 678
 679 DEFINE_MAIN_FUNCTION(run);