src/journal/coredumpctl.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2012 Zbigniew Jędrzejewski-Szmek
   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 <locale.h>
  23 #include <stdio.h>
  24 #include <string.h>
  25 #include <getopt.h>
  26 #include <fcntl.h>
  27 #include <unistd.h>
  28
  29 #include <systemd/sd-journal.h>
  30
  31 #include "build.h"
  32 #include "set.h"
  33 #include "util.h"
  34 #include "log.h"
  35 #include "path-util.h"
  36 #include "pager.h"
  37 #include "macro.h"
  38 #include "journal-internal.h"
  39
  40 static enum {
  41         ACTION_NONE,
  42         ACTION_LIST,
  43         ACTION_DUMP,
  44         ACTION_GDB,
  45 } arg_action = ACTION_LIST;
  46
  47 static FILE* output = NULL;
  48 static char* field = NULL;
  49
  50 static int arg_no_pager = false;
  51 static int arg_no_legend = false;
  52
  53 static Set *new_matches(void) {
  54         Set *set;
  55         char *tmp;
  56         int r;
  57
  58         set = set_new(trivial_hash_func, trivial_compare_func);
  59         if (!set) {
  60                 log_oom();
  61                 return NULL;
  62         }
  63
  64         tmp = strdup("MESSAGE_ID=fc2e22bc6ee647b6b90729ab34a250b1");
  65         if (!tmp) {
  66                 log_oom();
  67                 set_free(set);
  68                 return NULL;
  69         }
  70
  71         r = set_consume(set, tmp);
  72         if (r < 0) {
  73                 log_error("failed to add to set: %s", strerror(-r));
  74                 set_free(set);
  75                 return NULL;
  76         }
  77
  78         return set;
  79 }
  80
  81 static int help(void) {
  82         printf("%s [OPTIONS...] [MATCHES...]\n\n"
  83                "List or retrieve coredumps from the journal.\n\n"
  84                "Flags:\n"
  85                "  -o --output=FILE  Write output to FILE\n"
  86                "     --no-pager     Do not pipe output into a pager\n"
  87                "     --no-legend    Do not print the column headers.\n\n"
  88
  89                "Commands:\n"
  90                "  -h --help         Show this help\n"
  91                "  --version         Print version string\n"
  92                "  -F --field=FIELD  List all values a certain field takes\n"
  93                "  gdb               Start gdb for the first matching coredump\n"
  94                "  list              List available coredumps\n"
  95                "  dump PID          Print coredump to stdout\n"
  96                "  dump PATH         Print coredump to stdout\n"
  97                , program_invocation_short_name);
  98
  99         return 0;
 100 }
 101
 102 static int add_match(Set *set, const char *match) {
 103         int r = -ENOMEM;
 104         unsigned pid;
 105         const char* prefix;
 106         char *pattern = NULL;
 107         _cleanup_free_ char *p = NULL;
 108
 109         if (strchr(match, '='))
 110                 prefix = "";
 111         else if (strchr(match, '/')) {
 112                 p = path_make_absolute_cwd(match);
 113                 if (!p)
 114                         goto fail;
 115
 116                 match = p;
 117                 prefix = "COREDUMP_EXE=";
 118         }
 119         else if (safe_atou(match, &pid) == 0)
 120                 prefix = "COREDUMP_PID=";
 121         else
 122                 prefix = "COREDUMP_COMM=";
 123
 124         pattern = strjoin(prefix, match, NULL);
 125         if (!pattern)
 126                 goto fail;
 127
 128         log_debug("Adding pattern: %s", pattern);
 129         r = set_put(set, pattern);
 130         if (r < 0) {
 131                 log_error("Failed to add pattern '%s': %s",
 132                           pattern, strerror(-r));
 133                 free(pattern);
 134                 goto fail;
 135         }
 136
 137         return 0;
 138 fail:
 139         log_error("Failed to add match: %s", strerror(-r));
 140         return r;
 141 }
 142
 143 static int parse_argv(int argc, char *argv[], Set *matches) {
 144         enum {
 145                 ARG_VERSION = 0x100,
 146                 ARG_NO_PAGER,
 147                 ARG_NO_LEGEND,
 148         };
 149
 150         int r, c;
 151
 152         static const struct option options[] = {
 153                 { "help",         no_argument,       NULL, 'h'           },
 154                 { "version" ,     no_argument,       NULL, ARG_VERSION   },
 155                 { "no-pager",     no_argument,       NULL, ARG_NO_PAGER  },
 156                 { "no-legend",    no_argument,       NULL, ARG_NO_LEGEND },
 157                 { "output",       required_argument, NULL, 'o'           },
 158                 { "field",        required_argument, NULL, 'F'           },
 159                 {}
 160         };
 161
 162         assert(argc >= 0);
 163         assert(argv);
 164
 165         while ((c = getopt_long(argc, argv, "ho:F:", options, NULL)) >= 0)
 166                 switch(c) {
 167
 168                 case 'h':
 169                         arg_action = ACTION_NONE;
 170                         return help();
 171
 172                 case ARG_VERSION:
 173                         arg_action = ACTION_NONE;
 174                         puts(PACKAGE_STRING);
 175                         puts(SYSTEMD_FEATURES);
 176                         return 0;
 177
 178                 case ARG_NO_PAGER:
 179                         arg_no_pager = true;
 180                         break;
 181
 182                 case ARG_NO_LEGEND:
 183                         arg_no_legend = true;
 184                         break;
 185
 186                 case 'o':
 187                         if (output) {
 188                                 log_error("cannot set output more than once");
 189                                 return -EINVAL;
 190                         }
 191
 192                         output = fopen(optarg, "we");
 193                         if (!output) {
 194                                 log_error("writing to '%s': %m", optarg);
 195                                 return -errno;
 196                         }
 197
 198                         break;
 199
 200                 case 'F':
 201                         if (field) {
 202                                 log_error("cannot use --field/-F more than once");
 203                                 return -EINVAL;
 204                         }
 205
 206                         field = optarg;
 207                         break;
 208
 209                 case '?':
 210                         return -EINVAL;
 211
 212                 default:
 213                         assert_not_reached("Unhandled option");
 214                 }
 215
 216         if (optind < argc) {
 217                 const char *cmd = argv[optind++];
 218                 if (streq(cmd, "list"))
 219                         arg_action = ACTION_LIST;
 220                 else if (streq(cmd, "dump"))
 221                         arg_action = ACTION_DUMP;
 222                 else if (streq(cmd, "gdb"))
 223                         arg_action = ACTION_GDB;
 224                 else {
 225                         log_error("Unknown action '%s'", cmd);
 226                         return -EINVAL;
 227                 }
 228         }
 229
 230         if (field && arg_action != ACTION_LIST) {
 231                 log_error("Option --field/-F only makes sense with list");
 232                 return -EINVAL;
 233         }
 234
 235         while (optind < argc) {
 236                 r = add_match(matches, argv[optind]);
 237                 if (r != 0)
 238                         return r;
 239                 optind++;
 240         }
 241
 242         return 0;
 243 }
 244
 245 static int retrieve(const void *data,
 246                     size_t len,
 247                     const char *name,
 248                     const char **var) {
 249
 250         size_t ident;
 251
 252         ident = strlen(name) + 1; /* name + "=" */
 253
 254         if (len < ident)
 255                 return 0;
 256
 257         if (memcmp(data, name, ident - 1) != 0)
 258                 return 0;
 259
 260         if (((const char*) data)[ident - 1] != '=')
 261                 return 0;
 262
 263         *var = strndup((const char*)data + ident, len - ident);
 264         if (!*var)
 265                 return log_oom();
 266
 267         return 0;
 268 }
 269
 270 static void print_field(FILE* file, sd_journal *j) {
 271         _cleanup_free_ const char *value = NULL;
 272         const void *d;
 273         size_t l;
 274
 275         assert(field);
 276
 277         SD_JOURNAL_FOREACH_DATA(j, d, l)
 278                 retrieve(d, l, field, &value);
 279         if (value)
 280                 fprintf(file, "%s\n", value);
 281 }
 282
 283 static int print_entry(FILE* file, sd_journal *j, int had_legend) {
 284         _cleanup_free_ const char
 285                 *pid = NULL, *uid = NULL, *gid = NULL,
 286                 *sgnl = NULL, *exe = NULL;
 287         const void *d;
 288         size_t l;
 289         usec_t t;
 290         char buf[FORMAT_TIMESTAMP_MAX];
 291         int r;
 292
 293         SD_JOURNAL_FOREACH_DATA(j, d, l) {
 294                 retrieve(d, l, "COREDUMP_PID", &pid);
 295                 retrieve(d, l, "COREDUMP_PID", &pid);
 296                 retrieve(d, l, "COREDUMP_UID", &uid);
 297                 retrieve(d, l, "COREDUMP_GID", &gid);
 298                 retrieve(d, l, "COREDUMP_SIGNAL", &sgnl);
 299                 retrieve(d, l, "COREDUMP_EXE", &exe);
 300                 if (!exe)
 301                         retrieve(d, l, "COREDUMP_COMM", &exe);
 302                 if (!exe)
 303                         retrieve(d, l, "COREDUMP_CMDLINE", &exe);
 304         }
 305
 306         if (!pid && !uid && !gid && !sgnl && !exe) {
 307                 log_warning("Empty coredump log entry");
 308                 return -EINVAL;
 309         }
 310
 311         r = sd_journal_get_realtime_usec(j, &t);
 312         if (r < 0) {
 313                 log_error("Failed to get realtime timestamp: %s", strerror(-r));
 314                 return r;
 315         }
 316
 317         format_timestamp(buf, sizeof(buf), t);
 318
 319         if (!had_legend && !arg_no_legend)
 320                 fprintf(file, "%-*s %*s %*s %*s %*s %s\n",
 321                         FORMAT_TIMESTAMP_MAX-1, "TIME",
 322                         6, "PID",
 323                         5, "UID",
 324                         5, "GID",
 325                         3, "SIG",
 326                            "EXE");
 327
 328         fprintf(file, "%*s %*s %*s %*s %*s %s\n",
 329                 FORMAT_TIMESTAMP_MAX-1, buf,
 330                 6, pid,
 331                 5, uid,
 332                 5, gid,
 333                 3, sgnl,
 334                 exe);
 335
 336         return 0;
 337 }
 338
 339 static int dump_list(sd_journal *j) {
 340         int found = 0;
 341
 342         assert(j);
 343
 344         /* The coredumps are likely to compressed, and for just
 345          * listing them we don't need to decompress them, so let's
 346          * pick a fairly low data threshold here */
 347         sd_journal_set_data_threshold(j, 4096);
 348
 349         SD_JOURNAL_FOREACH(j) {
 350                 if (field)
 351                         print_field(stdout, j);
 352                 else
 353                         print_entry(stdout, j, found++);
 354         }
 355
 356         if (!field && !found) {
 357                 log_notice("No coredumps found");
 358                 return -ESRCH;
 359         }
 360
 361         return 0;
 362 }
 363
 364 static int focus(sd_journal *j) {
 365         int r;
 366
 367         r = sd_journal_seek_tail(j);
 368         if (r == 0)
 369                 r = sd_journal_previous(j);
 370         if (r < 0) {
 371                 log_error("Failed to search journal: %s", strerror(-r));
 372                 return r;
 373         }
 374         if (r == 0) {
 375                 log_error("No match found");
 376                 return -ESRCH;
 377         }
 378         return r;
 379 }
 380
 381 static int dump_core(sd_journal* j) {
 382         const void *data;
 383         size_t len, ret;
 384         int r;
 385
 386         assert(j);
 387
 388         /* We want full data, nothing truncated. */
 389         sd_journal_set_data_threshold(j, 0);
 390
 391         r = focus(j);
 392         if (r < 0)
 393                 return r;
 394
 395         print_entry(output ? stdout : stderr, j, false);
 396
 397         if (on_tty() && !output) {
 398                 log_error("Refusing to dump core to tty");
 399                 return -ENOTTY;
 400         }
 401
 402         r = sd_journal_get_data(j, "COREDUMP", (const void**) &data, &len);
 403         if (r < 0) {
 404                 log_error("Failed to retrieve COREDUMP field: %s", strerror(-r));
 405                 return r;
 406         }
 407
 408         assert(len >= 9);
 409         data = (const uint8_t*) data + 9;
 410         len -= 9;
 411
 412         ret = fwrite(data, len, 1, output ? output : stdout);
 413         if (ret != 1) {
 414                 log_error("dumping coredump: %m (%zu)", ret);
 415                 return -errno;
 416         }
 417
 418         r = sd_journal_previous(j);
 419         if (r >= 0)
 420                 log_warning("More than one entry matches, ignoring rest.");
 421
 422         return 0;
 423 }
 424
 425 static int run_gdb(sd_journal *j) {
 426         char path[] = "/var/tmp/coredump-XXXXXX";
 427         const void *data;
 428         size_t len;
 429         ssize_t sz;
 430         pid_t pid;
 431         _cleanup_free_ char *exe = NULL;
 432         int r;
 433         _cleanup_close_ int fd = -1;
 434         siginfo_t st;
 435
 436         assert(j);
 437
 438         sd_journal_set_data_threshold(j, 0);
 439
 440         r = focus(j);
 441         if (r < 0)
 442                 return r;
 443
 444         print_entry(stdout, j, false);
 445
 446         r = sd_journal_get_data(j, "COREDUMP_EXE", (const void**) &data, &len);
 447         if (r < 0) {
 448                 log_error("Failed to retrieve COREDUMP_EXE field: %s", strerror(-r));
 449                 return r;
 450         }
 451
 452         assert(len >= 13);
 453         data = (const uint8_t*) data + 13;
 454         len -= 13;
 455
 456         exe = strndup(data, len);
 457         if (!exe)
 458                 return log_oom();
 459
 460         if (endswith(exe, " (deleted)")) {
 461                 log_error("Binary already deleted.");
 462                 return -ENOENT;
 463         }
 464
 465         r = sd_journal_get_data(j, "COREDUMP", (const void**) &data, &len);
 466         if (r < 0) {
 467                 log_error("Failed to retrieve COREDUMP field: %s", strerror(-r));
 468                 return r;
 469         }
 470
 471         assert(len >= 9);
 472         data = (const uint8_t*) data + 9;
 473         len -= 9;
 474
 475         fd = mkostemp_safe(path, O_WRONLY|O_CLOEXEC);
 476         if (fd < 0) {
 477                 log_error("Failed to create temporary file: %m");
 478                 return -errno;
 479         }
 480
 481         sz = write(fd, data, len);
 482         if (sz < 0) {
 483                 log_error("Failed to write temporary file: %m");
 484                 r = -errno;
 485                 goto finish;
 486         }
 487         if (sz != (ssize_t) len) {
 488                 log_error("Short write to temporary file.");
 489                 r = -EIO;
 490                 goto finish;
 491         }
 492
 493         fd = safe_close(fd);
 494
 495         pid = fork();
 496         if (pid < 0) {
 497                 log_error("Failed to fork(): %m");
 498                 r = -errno;
 499                 goto finish;
 500         }
 501         if (pid == 0) {
 502                 execlp("gdb", "gdb", exe, path, NULL);
 503                 log_error("Failed to invoke gdb: %m");
 504                 _exit(1);
 505         }
 506
 507         r = wait_for_terminate(pid, &st);
 508         if (r < 0) {
 509                 log_error("Failed to wait for gdb: %m");
 510                 goto finish;
 511         }
 512
 513         r = st.si_code == CLD_EXITED ? st.si_status : 255;
 514
 515 finish:
 516         unlink(path);
 517         return r;
 518 }
 519
 520 int main(int argc, char *argv[]) {
 521         _cleanup_journal_close_ sd_journal*j = NULL;
 522         const char* match;
 523         Iterator it;
 524         int r = 0;
 525         _cleanup_set_free_free_ Set *matches = NULL;
 526
 527         setlocale(LC_ALL, "");
 528         log_parse_environment();
 529         log_open();
 530
 531         matches = new_matches();
 532         if (!matches) {
 533                 r = -ENOMEM;
 534                 goto end;
 535         }
 536
 537         r = parse_argv(argc, argv, matches);
 538         if (r < 0)
 539                 goto end;
 540
 541         if (arg_action == ACTION_NONE)
 542                 goto end;
 543
 544         r = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY);
 545         if (r < 0) {
 546                 log_error("Failed to open journal: %s", strerror(-r));
 547                 goto end;
 548         }
 549
 550         SET_FOREACH(match, matches, it) {
 551                 r = sd_journal_add_match(j, match, strlen(match));
 552                 if (r != 0) {
 553                         log_error("Failed to add match '%s': %s",
 554                                   match, strerror(-r));
 555                         goto end;
 556                 }
 557         }
 558
 559         if (_unlikely_(log_get_max_level() >= LOG_PRI(LOG_DEBUG))) {
 560                 _cleanup_free_ char *filter;
 561
 562                 filter = journal_make_match_string(j);
 563                 log_debug("Journal filter: %s", filter);
 564         }
 565
 566         switch(arg_action) {
 567
 568         case ACTION_LIST:
 569                 if (!arg_no_pager)
 570                         pager_open(false);
 571
 572                 r = dump_list(j);
 573                 break;
 574
 575         case ACTION_DUMP:
 576                 r = dump_core(j);
 577                 break;
 578
 579         case  ACTION_GDB:
 580                 r = run_gdb(j);
 581                 break;
 582
 583         default:
 584                 assert_not_reached("Shouldn't be here");
 585         }
 586
 587 end:
 588         pager_close();
 589
 590         if (output)
 591                 fclose(output);
 592
 593         return r >= 0 ? r : EXIT_FAILURE;
 594 }