src/delta/delta.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <errno.h>
   4 #include <getopt.h>
   5 #include <string.h>
   6 #include <sys/prctl.h>
   7 #include <unistd.h>
   8
   9 #include "alloc-util.h"
  10 #include "dirent-util.h"
  11 #include "fd-util.h"
  12 #include "fs-util.h"
  13 #include "hashmap.h"
  14 #include "locale-util.h"
  15 #include "log.h"
  16 #include "main-func.h"
  17 #include "pager.h"
  18 #include "parse-util.h"
  19 #include "path-util.h"
  20 #include "process-util.h"
  21 #include "signal-util.h"
  22 #include "stat-util.h"
  23 #include "string-util.h"
  24 #include "strv.h"
  25 #include "terminal-util.h"
  26 #include "util.h"
  27
  28 static const char prefixes[] =
  29         "/etc\0"
  30         "/run\0"
  31         "/usr/local/lib\0"
  32         "/usr/local/share\0"
  33         "/usr/lib\0"
  34         "/usr/share\0"
  35 #if HAVE_SPLIT_USR
  36         "/lib\0"
  37 #endif
  38         ;
  39
  40 static const char suffixes[] =
  41         "sysctl.d\0"
  42         "tmpfiles.d\0"
  43         "modules-load.d\0"
  44         "binfmt.d\0"
  45         "systemd/system\0"
  46         "systemd/user\0"
  47         "systemd/system-preset\0"
  48         "systemd/user-preset\0"
  49         "udev/rules.d\0"
  50         "modprobe.d\0";
  51
  52 static const char have_dropins[] =
  53         "systemd/system\0"
  54         "systemd/user\0";
  55
  56 static PagerFlags arg_pager_flags = 0;
  57 static int arg_diff = -1;
  58
  59 static enum {
  60         SHOW_MASKED     = 1 << 0,
  61         SHOW_EQUIVALENT = 1 << 1,
  62         SHOW_REDIRECTED = 1 << 2,
  63         SHOW_OVERRIDDEN = 1 << 3,
  64         SHOW_UNCHANGED  = 1 << 4,
  65         SHOW_EXTENDED   = 1 << 5,
  66
  67         SHOW_DEFAULTS =
  68         (SHOW_MASKED | SHOW_EQUIVALENT | SHOW_REDIRECTED | SHOW_OVERRIDDEN | SHOW_EXTENDED)
  69 } arg_flags = 0;
  70
  71 static int equivalent(const char *a, const char *b) {
  72         _cleanup_free_ char *x = NULL, *y = NULL;
  73         int r;
  74
  75         r = chase_symlinks(a, NULL, CHASE_TRAIL_SLASH, &x);
  76         if (r < 0)
  77                 return r;
  78
  79         r = chase_symlinks(b, NULL, CHASE_TRAIL_SLASH, &y);
  80         if (r < 0)
  81                 return r;
  82
  83         return path_equal(x, y);
  84 }
  85
  86 static int notify_override_masked(const char *top, const char *bottom) {
  87         if (!(arg_flags & SHOW_MASKED))
  88                 return 0;
  89
  90         printf("%s%s%s     %s %s %s\n",
  91                ansi_highlight_red(), "[MASKED]", ansi_normal(),
  92                top, special_glyph(ARROW), bottom);
  93         return 1;
  94 }
  95
  96 static int notify_override_equivalent(const char *top, const char *bottom) {
  97         if (!(arg_flags & SHOW_EQUIVALENT))
  98                 return 0;
  99
 100         printf("%s%s%s %s %s %s\n",
 101                ansi_highlight_green(), "[EQUIVALENT]", ansi_normal(),
 102                top, special_glyph(ARROW), bottom);
 103         return 1;
 104 }
 105
 106 static int notify_override_redirected(const char *top, const char *bottom) {
 107         if (!(arg_flags & SHOW_REDIRECTED))
 108                 return 0;
 109
 110         printf("%s%s%s %s %s %s\n",
 111                ansi_highlight(), "[REDIRECTED]", ansi_normal(),
 112                top, special_glyph(ARROW), bottom);
 113         return 1;
 114 }
 115
 116 static int notify_override_overridden(const char *top, const char *bottom) {
 117         if (!(arg_flags & SHOW_OVERRIDDEN))
 118                 return 0;
 119
 120         printf("%s%s%s %s %s %s\n",
 121                ansi_highlight(), "[OVERRIDDEN]", ansi_normal(),
 122                top, special_glyph(ARROW), bottom);
 123         return 1;
 124 }
 125
 126 static int notify_override_extended(const char *top, const char *bottom) {
 127         if (!(arg_flags & SHOW_EXTENDED))
 128                return 0;
 129
 130         printf("%s%s%s   %s %s %s\n",
 131                ansi_highlight(), "[EXTENDED]", ansi_normal(),
 132                top, special_glyph(ARROW), bottom);
 133         return 1;
 134 }
 135
 136 static int notify_override_unchanged(const char *f) {
 137         if (!(arg_flags & SHOW_UNCHANGED))
 138                 return 0;
 139
 140         printf("[UNCHANGED]  %s\n", f);
 141         return 1;
 142 }
 143
 144 static int found_override(const char *top, const char *bottom) {
 145         _cleanup_free_ char *dest = NULL;
 146         pid_t pid;
 147         int r;
 148
 149         assert(top);
 150         assert(bottom);
 151
 152         if (null_or_empty_path(top) > 0)
 153                 return notify_override_masked(top, bottom);
 154
 155         r = readlink_malloc(top, &dest);
 156         if (r >= 0) {
 157                 if (equivalent(dest, bottom) > 0)
 158                         return notify_override_equivalent(top, bottom);
 159                 else
 160                         return notify_override_redirected(top, bottom);
 161         }
 162
 163         r = notify_override_overridden(top, bottom);
 164         if (!arg_diff)
 165                 return r;
 166
 167         putchar('\n');
 168
 169         fflush(stdout);
 170
 171         r = safe_fork("(diff)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_CLOSE_ALL_FDS|FORK_LOG, &pid);
 172         if (r < 0)
 173                 return r;
 174         if (r == 0) {
 175                 execlp("diff", "diff", "-us", "--", bottom, top, NULL);
 176                 log_open();
 177                 log_error_errno(errno, "Failed to execute diff: %m");
 178                 _exit(EXIT_FAILURE);
 179         }
 180
 181         (void) wait_for_terminate_and_check("diff", pid, WAIT_LOG_ABNORMAL);
 182         putchar('\n');
 183
 184         return r;
 185 }
 186
 187 static int enumerate_dir_d(
 188                 OrderedHashmap *top,
 189                 OrderedHashmap *bottom,
 190                 OrderedHashmap *drops,
 191                 const char *toppath, const char *drop) {
 192
 193         _cleanup_free_ char *unit = NULL;
 194         _cleanup_free_ char *path = NULL;
 195         _cleanup_strv_free_ char **list = NULL;
 196         char **file;
 197         char *c;
 198         int r;
 199
 200         assert(!endswith(drop, "/"));
 201
 202         path = strjoin(toppath, "/", drop);
 203         if (!path)
 204                 return -ENOMEM;
 205
 206         log_debug("Looking at %s", path);
 207
 208         unit = strdup(drop);
 209         if (!unit)
 210                 return -ENOMEM;
 211
 212         c = strrchr(unit, '.');
 213         if (!c)
 214                 return -EINVAL;
 215         *c = 0;
 216
 217         r = get_files_in_directory(path, &list);
 218         if (r < 0)
 219                 return log_error_errno(r, "Failed to enumerate %s: %m", path);
 220
 221         strv_sort(list);
 222
 223         STRV_FOREACH(file, list) {
 224                 OrderedHashmap *h;
 225                 int k;
 226                 char *p;
 227                 char *d;
 228
 229                 if (!endswith(*file, ".conf"))
 230                         continue;
 231
 232                 p = strjoin(path, "/", *file);
 233                 if (!p)
 234                         return -ENOMEM;
 235                 d = p + strlen(toppath) + 1;
 236
 237                 log_debug("Adding at top: %s %s %s", d, special_glyph(ARROW), p);
 238                 k = ordered_hashmap_put(top, d, p);
 239                 if (k >= 0) {
 240                         p = strdup(p);
 241                         if (!p)
 242                                 return -ENOMEM;
 243                         d = p + strlen(toppath) + 1;
 244                 } else if (k != -EEXIST) {
 245                         free(p);
 246                         return k;
 247                 }
 248
 249                 log_debug("Adding at bottom: %s %s %s", d, special_glyph(ARROW), p);
 250                 free(ordered_hashmap_remove(bottom, d));
 251                 k = ordered_hashmap_put(bottom, d, p);
 252                 if (k < 0) {
 253                         free(p);
 254                         return k;
 255                 }
 256
 257                 h = ordered_hashmap_get(drops, unit);
 258                 if (!h) {
 259                         h = ordered_hashmap_new(&string_hash_ops);
 260                         if (!h)
 261                                 return -ENOMEM;
 262                         ordered_hashmap_put(drops, unit, h);
 263                         unit = strdup(unit);
 264                         if (!unit)
 265                                 return -ENOMEM;
 266                 }
 267
 268                 p = strdup(p);
 269                 if (!p)
 270                         return -ENOMEM;
 271
 272                 log_debug("Adding to drops: %s %s %s %s %s",
 273                           unit, special_glyph(ARROW), basename(p), special_glyph(ARROW), p);
 274                 k = ordered_hashmap_put(h, basename(p), p);
 275                 if (k < 0) {
 276                         free(p);
 277                         if (k != -EEXIST)
 278                                 return k;
 279                 }
 280         }
 281         return 0;
 282 }
 283
 284 static int enumerate_dir(
 285                 OrderedHashmap *top,
 286                 OrderedHashmap *bottom,
 287                 OrderedHashmap *drops,
 288                 const char *path, bool dropins) {
 289
 290         _cleanup_closedir_ DIR *d = NULL;
 291         struct dirent *de;
 292         _cleanup_strv_free_ char **files = NULL, **dirs = NULL;
 293         size_t n_files = 0, allocated_files = 0, n_dirs = 0, allocated_dirs = 0;
 294         char **t;
 295         int r;
 296
 297         assert(top);
 298         assert(bottom);
 299         assert(drops);
 300         assert(path);
 301
 302         log_debug("Looking at %s", path);
 303
 304         d = opendir(path);
 305         if (!d) {
 306                 if (errno == ENOENT)
 307                         return 0;
 308
 309                 return log_error_errno(errno, "Failed to open %s: %m", path);
 310         }
 311
 312         FOREACH_DIRENT_ALL(de, d, return -errno) {
 313                 dirent_ensure_type(d, de);
 314
 315                 if (dropins && de->d_type == DT_DIR && endswith(de->d_name, ".d")) {
 316                         if (!GREEDY_REALLOC0(dirs, allocated_dirs, n_dirs + 2))
 317                                 return -ENOMEM;
 318
 319                         dirs[n_dirs] = strdup(de->d_name);
 320                         if (!dirs[n_dirs])
 321                                 return -ENOMEM;
 322                         n_dirs ++;
 323                 }
 324
 325                 if (!dirent_is_file(de))
 326                         continue;
 327
 328                 if (!GREEDY_REALLOC0(files, allocated_files, n_files + 2))
 329                         return -ENOMEM;
 330
 331                 files[n_files] = strdup(de->d_name);
 332                 if (!files[n_files])
 333                         return -ENOMEM;
 334                 n_files ++;
 335         }
 336
 337         strv_sort(dirs);
 338         strv_sort(files);
 339
 340         STRV_FOREACH(t, dirs) {
 341                 r = enumerate_dir_d(top, bottom, drops, path, *t);
 342                 if (r < 0)
 343                         return r;
 344         }
 345
 346         STRV_FOREACH(t, files) {
 347                 _cleanup_free_ char *p = NULL;
 348
 349                 p = strjoin(path, "/", *t);
 350                 if (!p)
 351                         return -ENOMEM;
 352
 353                 log_debug("Adding at top: %s %s %s", basename(p), special_glyph(ARROW), p);
 354                 r = ordered_hashmap_put(top, basename(p), p);
 355                 if (r >= 0) {
 356                         p = strdup(p);
 357                         if (!p)
 358                                 return -ENOMEM;
 359                 } else if (r != -EEXIST)
 360                         return r;
 361
 362                 log_debug("Adding at bottom: %s %s %s", basename(p), special_glyph(ARROW), p);
 363                 free(ordered_hashmap_remove(bottom, basename(p)));
 364                 r = ordered_hashmap_put(bottom, basename(p), p);
 365                 if (r < 0)
 366                         return r;
 367                 p = NULL;
 368         }
 369
 370         return 0;
 371 }
 372
 373 static bool should_skip_path(const char *prefix, const char *suffix) {
 374 #if HAVE_SPLIT_USR
 375         _cleanup_free_ char *target = NULL;
 376         const char *p;
 377         char *dirname;
 378
 379         dirname = strjoina(prefix, "/", suffix);
 380
 381         if (chase_symlinks(dirname, NULL, 0, &target) < 0)
 382                 return false;
 383
 384         NULSTR_FOREACH(p, prefixes) {
 385                 if (path_startswith(dirname, p))
 386                         continue;
 387
 388                 if (path_equal(target, strjoina(p, "/", suffix))) {
 389                         log_debug("%s redirects to %s, skipping.", dirname, target);
 390                         return true;
 391                 }
 392         }
 393 #endif
 394         return false;
 395 }
 396
 397 static int process_suffix(const char *suffix, const char *onlyprefix) {
 398         const char *p;
 399         char *f;
 400         OrderedHashmap *top, *bottom, *drops;
 401         OrderedHashmap *h;
 402         char *key;
 403         int r = 0, k;
 404         Iterator i, j;
 405         int 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))
 426                         continue;
 427
 428                 t = strjoin(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, i) {
 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, j)
 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, i) {
 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         log_error("Invalid suffix specification %s.", arg);
 516         return -EINVAL;
 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
 539         return 0;
 540 }
 541
 542 static int parse_flags(const char *flag_str, int flags) {
 543         const char *word, *state;
 544         size_t l;
 545
 546         FOREACH_WORD_SEPARATOR(word, l, flag_str, ",", state) {
 547                 if (strneq("masked", word, l))
 548                         flags |= SHOW_MASKED;
 549                 else if (strneq ("equivalent", word, l))
 550                         flags |= SHOW_EQUIVALENT;
 551                 else if (strneq("redirected", word, l))
 552                         flags |= SHOW_REDIRECTED;
 553                 else if (strneq("overridden", word, l))
 554                         flags |= SHOW_OVERRIDDEN;
 555                 else if (strneq("unchanged", word, l))
 556                         flags |= SHOW_UNCHANGED;
 557                 else if (strneq("extended", word, l))
 558                         flags |= SHOW_EXTENDED;
 559                 else if (strneq("default", word, l))
 560                         flags |= SHOW_DEFAULTS;
 561                 else
 562                         return -EINVAL;
 563         }
 564         return flags;
 565 }
 566
 567 static int parse_argv(int argc, char *argv[]) {
 568
 569         enum {
 570                 ARG_NO_PAGER = 0x100,
 571                 ARG_DIFF,
 572                 ARG_VERSION
 573         };
 574
 575         static const struct option options[] = {
 576                 { "help",      no_argument,       NULL, 'h'          },
 577                 { "version",   no_argument,       NULL, ARG_VERSION  },
 578                 { "no-pager",  no_argument,       NULL, ARG_NO_PAGER },
 579                 { "diff",      optional_argument, NULL, ARG_DIFF     },
 580                 { "type",      required_argument, NULL, 't'          },
 581                 {}
 582         };
 583
 584         int c;
 585
 586         assert(argc >= 1);
 587         assert(argv);
 588
 589         while ((c = getopt_long(argc, argv, "ht:", options, NULL)) >= 0)
 590
 591                 switch (c) {
 592
 593                 case 'h':
 594                         return help();
 595
 596                 case ARG_VERSION:
 597                         return version();
 598
 599                 case ARG_NO_PAGER:
 600                         arg_pager_flags |= PAGER_DISABLE;
 601                         break;
 602
 603                 case 't': {
 604                         int f;
 605                         f = parse_flags(optarg, arg_flags);
 606                         if (f < 0) {
 607                                 log_error("Failed to parse flags field.");
 608                                 return -EINVAL;
 609                         }
 610                         arg_flags = f;
 611                         break;
 612                 }
 613
 614                 case ARG_DIFF:
 615                         if (!optarg)
 616                                 arg_diff = 1;
 617                         else {
 618                                 int b;
 619
 620                                 b = parse_boolean(optarg);
 621                                 if (b < 0) {
 622                                         log_error("Failed to parse diff boolean.");
 623                                         return -EINVAL;
 624                                 }
 625
 626                                 arg_diff = b;
 627                         }
 628                         break;
 629
 630                 case '?':
 631                         return -EINVAL;
 632
 633                 default:
 634                         assert_not_reached("Unhandled option");
 635                 }
 636
 637         return 1;
 638 }
 639
 640 static int run(int argc, char *argv[]) {
 641         int r, k, n_found = 0;
 642
 643         log_parse_environment();
 644         log_open();
 645
 646         r = parse_argv(argc, argv);
 647         if (r <= 0)
 648                 return r;
 649
 650         if (arg_flags == 0)
 651                 arg_flags = SHOW_DEFAULTS;
 652
 653         if (arg_diff < 0)
 654                 arg_diff = !!(arg_flags & SHOW_OVERRIDDEN);
 655         else if (arg_diff)
 656                 arg_flags |= SHOW_OVERRIDDEN;
 657
 658         (void) pager_open(arg_pager_flags);
 659
 660         if (optind < argc) {
 661                 int i;
 662
 663                 for (i = optind; i < argc; i++) {
 664                         path_simplify(argv[i], false);
 665
 666                         k = process_suffix_chop(argv[i]);
 667                         if (k < 0)
 668                                 r = k;
 669                         else
 670                                 n_found += k;
 671                 }
 672
 673         } else {
 674                 k = process_suffixes(NULL);
 675                 if (k < 0)
 676                         r = k;
 677                 else
 678                         n_found += k;
 679         }
 680
 681         if (r >= 0)
 682                 printf("%s%i overridden configuration files found.\n", n_found ? "\n" : "", n_found);
 683         return r;
 684 }
 685
 686 DEFINE_MAIN_FUNCTION(run);