src/shared/log.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <stdarg.h>
  23 #include <stdio.h>
  24 #include <errno.h>
  25 #include <unistd.h>
  26 #include <fcntl.h>
  27 #include <sys/socket.h>
  28 #include <sys/un.h>
  29 #include <stddef.h>
  30 #include <printf.h>
  31
  32 #include "log.h"
  33 #include "util.h"
  34 #include "missing.h"
  35 #include "macro.h"
  36 #include "socket-util.h"
  37
  38 #define SNDBUF_SIZE (8*1024*1024)
  39
  40 static LogTarget log_target = LOG_TARGET_CONSOLE;
  41 static int log_max_level = LOG_INFO;
  42 static int log_facility = LOG_DAEMON;
  43
  44 static int console_fd = STDERR_FILENO;
  45 static int syslog_fd = -1;
  46 static int kmsg_fd = -1;
  47 static int journal_fd = -1;
  48
  49 static bool syslog_is_stream = false;
  50
  51 static bool show_color = false;
  52 static bool show_location = false;
  53
  54 static bool upgrade_syslog_to_journal = false;
  55
  56 /* Akin to glibc's __abort_msg; which is private and we hence cannot
  57  * use here. */
  58 static char *log_abort_msg = NULL;
  59
  60 void log_close_console(void) {
  61
  62         if (console_fd < 0)
  63                 return;
  64
  65         if (getpid() == 1) {
  66                 if (console_fd >= 3)
  67                         safe_close(console_fd);
  68
  69                 console_fd = -1;
  70         }
  71 }
  72
  73 static int log_open_console(void) {
  74
  75         if (console_fd >= 0)
  76                 return 0;
  77
  78         if (getpid() == 1) {
  79                 console_fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC);
  80                 if (console_fd < 0)
  81                         return console_fd;
  82         } else
  83                 console_fd = STDERR_FILENO;
  84
  85         return 0;
  86 }
  87
  88 void log_close_kmsg(void) {
  89         kmsg_fd = safe_close(kmsg_fd);
  90 }
  91
  92 static int log_open_kmsg(void) {
  93
  94         if (kmsg_fd >= 0)
  95                 return 0;
  96
  97         kmsg_fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC);
  98         if (kmsg_fd < 0)
  99                 return -errno;
 100
 101         return 0;
 102 }
 103
 104 void log_close_syslog(void) {
 105         syslog_fd = safe_close(syslog_fd);
 106 }
 107
 108 static int create_log_socket(int type) {
 109         struct timeval tv;
 110         int fd;
 111
 112         fd = socket(AF_UNIX, type|SOCK_CLOEXEC, 0);
 113         if (fd < 0)
 114                 return -errno;
 115
 116         fd_inc_sndbuf(fd, SNDBUF_SIZE);
 117
 118         /* We need a blocking fd here since we'd otherwise lose
 119         messages way too early. However, let's not hang forever in the
 120         unlikely case of a deadlock. */
 121         if (getpid() == 1)
 122                 timeval_store(&tv, 10 * USEC_PER_MSEC);
 123         else
 124                 timeval_store(&tv, 10 * USEC_PER_SEC);
 125         (void) setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv));
 126
 127         return fd;
 128 }
 129
 130 static int log_open_syslog(void) {
 131
 132         static const union sockaddr_union sa = {
 133                 .un.sun_family = AF_UNIX,
 134                 .un.sun_path = "/dev/log",
 135         };
 136
 137         int r;
 138
 139         if (syslog_fd >= 0)
 140                 return 0;
 141
 142         syslog_fd = create_log_socket(SOCK_DGRAM);
 143         if (syslog_fd < 0) {
 144                 r = syslog_fd;
 145                 goto fail;
 146         }
 147
 148         if (connect(syslog_fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) {
 149                 safe_close(syslog_fd);
 150
 151                 /* Some legacy syslog systems still use stream
 152                  * sockets. They really shouldn't. But what can we
 153                  * do... */
 154                 syslog_fd = create_log_socket(SOCK_STREAM);
 155                 if (syslog_fd < 0) {
 156                         r = syslog_fd;
 157                         goto fail;
 158                 }
 159
 160                 if (connect(syslog_fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) {
 161                         r = -errno;
 162                         goto fail;
 163                 }
 164
 165                 syslog_is_stream = true;
 166         } else
 167                 syslog_is_stream = false;
 168
 169         return 0;
 170
 171 fail:
 172         log_close_syslog();
 173         return r;
 174 }
 175
 176 void log_close_journal(void) {
 177         journal_fd = safe_close(journal_fd);
 178 }
 179
 180 static int log_open_journal(void) {
 181
 182         static const union sockaddr_union sa = {
 183                 .un.sun_family = AF_UNIX,
 184                 .un.sun_path = "/run/systemd/journal/socket",
 185         };
 186
 187         int r;
 188
 189         if (journal_fd >= 0)
 190                 return 0;
 191
 192         journal_fd = create_log_socket(SOCK_DGRAM);
 193         if (journal_fd < 0) {
 194                 r = journal_fd;
 195                 goto fail;
 196         }
 197
 198         if (connect(journal_fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) {
 199                 r = -errno;
 200                 goto fail;
 201         }
 202
 203         return 0;
 204
 205 fail:
 206         log_close_journal();
 207         return r;
 208 }
 209
 210 int log_open(void) {
 211         int r;
 212
 213         /* If we don't use the console we close it here, to not get
 214          * killed by SAK. If we don't use syslog we close it here so
 215          * that we are not confused by somebody deleting the socket in
 216          * the fs. If we don't use /dev/kmsg we still keep it open,
 217          * because there is no reason to close it. */
 218
 219         if (log_target == LOG_TARGET_NULL) {
 220                 log_close_journal();
 221                 log_close_syslog();
 222                 log_close_console();
 223                 return 0;
 224         }
 225
 226         if ((log_target != LOG_TARGET_AUTO && log_target != LOG_TARGET_SAFE) ||
 227             getpid() == 1 ||
 228             isatty(STDERR_FILENO) <= 0) {
 229
 230                 if (log_target == LOG_TARGET_AUTO ||
 231                     log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
 232                     log_target == LOG_TARGET_JOURNAL) {
 233                         r = log_open_journal();
 234                         if (r >= 0) {
 235                                 log_close_syslog();
 236                                 log_close_console();
 237                                 return r;
 238                         }
 239                 }
 240
 241                 if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
 242                     log_target == LOG_TARGET_SYSLOG) {
 243                         r = log_open_syslog();
 244                         if (r >= 0) {
 245                                 log_close_journal();
 246                                 log_close_console();
 247                                 return r;
 248                         }
 249                 }
 250
 251                 if (log_target == LOG_TARGET_AUTO ||
 252                     log_target == LOG_TARGET_SAFE ||
 253                     log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
 254                     log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
 255                     log_target == LOG_TARGET_KMSG) {
 256                         r = log_open_kmsg();
 257                         if (r >= 0) {
 258                                 log_close_journal();
 259                                 log_close_syslog();
 260                                 log_close_console();
 261                                 return r;
 262                         }
 263                 }
 264         }
 265
 266         log_close_journal();
 267         log_close_syslog();
 268
 269         return log_open_console();
 270 }
 271
 272 void log_set_target(LogTarget target) {
 273         assert(target >= 0);
 274         assert(target < _LOG_TARGET_MAX);
 275
 276         if (upgrade_syslog_to_journal) {
 277                 if (target == LOG_TARGET_SYSLOG)
 278                         target = LOG_TARGET_JOURNAL;
 279                 else if (target == LOG_TARGET_SYSLOG_OR_KMSG)
 280                         target = LOG_TARGET_JOURNAL_OR_KMSG;
 281         }
 282
 283         log_target = target;
 284 }
 285
 286 void log_close(void) {
 287         log_close_journal();
 288         log_close_syslog();
 289         log_close_kmsg();
 290         log_close_console();
 291 }
 292
 293 void log_forget_fds(void) {
 294         console_fd = kmsg_fd = syslog_fd = journal_fd = -1;
 295 }
 296
 297 void log_set_max_level(int level) {
 298         assert((level & LOG_PRIMASK) == level);
 299
 300         log_max_level = level;
 301 }
 302
 303 void log_set_facility(int facility) {
 304         log_facility = facility;
 305 }
 306
 307 static int write_to_console(
 308                 int level,
 309                 int error,
 310                 const char *file,
 311                 int line,
 312                 const char *func,
 313                 const char *object_field,
 314                 const char *object,
 315                 const char *buffer) {
 316
 317         char location[64], prefix[1 + DECIMAL_STR_MAX(int) + 2];
 318         struct iovec iovec[6] = {};
 319         unsigned n = 0;
 320         bool highlight;
 321
 322         if (console_fd < 0)
 323                 return 0;
 324
 325         if (log_target == LOG_TARGET_CONSOLE_PREFIXED) {
 326                 sprintf(prefix, "<%i>", level);
 327                 IOVEC_SET_STRING(iovec[n++], prefix);
 328         }
 329
 330         highlight = LOG_PRI(level) <= LOG_ERR && show_color;
 331
 332         if (show_location) {
 333                 snprintf(location, sizeof(location), "(%s:%i) ", file, line);
 334                 IOVEC_SET_STRING(iovec[n++], location);
 335         }
 336
 337         if (highlight)
 338                 IOVEC_SET_STRING(iovec[n++], ANSI_HIGHLIGHT_RED_ON);
 339         IOVEC_SET_STRING(iovec[n++], buffer);
 340         if (highlight)
 341                 IOVEC_SET_STRING(iovec[n++], ANSI_HIGHLIGHT_OFF);
 342         IOVEC_SET_STRING(iovec[n++], "\n");
 343
 344         if (writev(console_fd, iovec, n) < 0) {
 345
 346                 if (errno == EIO && getpid() == 1) {
 347
 348                         /* If somebody tried to kick us from our
 349                          * console tty (via vhangup() or suchlike),
 350                          * try to reconnect */
 351
 352                         log_close_console();
 353                         log_open_console();
 354
 355                         if (console_fd < 0)
 356                                 return 0;
 357
 358                         if (writev(console_fd, iovec, n) < 0)
 359                                 return -errno;
 360                 } else
 361                         return -errno;
 362         }
 363
 364         return 1;
 365 }
 366
 367 static int write_to_syslog(
 368                 int level,
 369                 int error,
 370                 const char *file,
 371                 int line,
 372                 const char *func,
 373                 const char *object_field,
 374                 const char *object,
 375                 const char *buffer) {
 376
 377         char header_priority[2 + DECIMAL_STR_MAX(int) + 1],
 378              header_time[64],
 379              header_pid[4 + DECIMAL_STR_MAX(pid_t) + 1];
 380         struct iovec iovec[5] = {};
 381         struct msghdr msghdr = {
 382                 .msg_iov = iovec,
 383                 .msg_iovlen = ELEMENTSOF(iovec),
 384         };
 385         time_t t;
 386         struct tm *tm;
 387
 388         if (syslog_fd < 0)
 389                 return 0;
 390
 391         xsprintf(header_priority, "<%i>", level);
 392
 393         t = (time_t) (now(CLOCK_REALTIME) / USEC_PER_SEC);
 394         tm = localtime(&t);
 395         if (!tm)
 396                 return -EINVAL;
 397
 398         if (strftime(header_time, sizeof(header_time), "%h %e %T ", tm) <= 0)
 399                 return -EINVAL;
 400
 401         xsprintf(header_pid, "["PID_FMT"]: ", getpid());
 402
 403         IOVEC_SET_STRING(iovec[0], header_priority);
 404         IOVEC_SET_STRING(iovec[1], header_time);
 405         IOVEC_SET_STRING(iovec[2], program_invocation_short_name);
 406         IOVEC_SET_STRING(iovec[3], header_pid);
 407         IOVEC_SET_STRING(iovec[4], buffer);
 408
 409         /* When using syslog via SOCK_STREAM separate the messages by NUL chars */
 410         if (syslog_is_stream)
 411                 iovec[4].iov_len++;
 412
 413         for (;;) {
 414                 ssize_t n;
 415
 416                 n = sendmsg(syslog_fd, &msghdr, MSG_NOSIGNAL);
 417                 if (n < 0)
 418                         return -errno;
 419
 420                 if (!syslog_is_stream ||
 421                     (size_t) n >= IOVEC_TOTAL_SIZE(iovec, ELEMENTSOF(iovec)))
 422                         break;
 423
 424                 IOVEC_INCREMENT(iovec, ELEMENTSOF(iovec), n);
 425         }
 426
 427         return 1;
 428 }
 429
 430 static int write_to_kmsg(
 431                 int level,
 432                 int error,
 433                 const char*file,
 434                 int line,
 435                 const char *func,
 436                 const char *object_field,
 437                 const char *object,
 438                 const char *buffer) {
 439
 440         char header_priority[2 + DECIMAL_STR_MAX(int) + 1],
 441              header_pid[4 + DECIMAL_STR_MAX(pid_t) + 1];
 442         struct iovec iovec[5] = {};
 443
 444         if (kmsg_fd < 0)
 445                 return 0;
 446
 447         xsprintf(header_priority, "<%i>", level);
 448         xsprintf(header_pid, "["PID_FMT"]: ", getpid());
 449
 450         IOVEC_SET_STRING(iovec[0], header_priority);
 451         IOVEC_SET_STRING(iovec[1], program_invocation_short_name);
 452         IOVEC_SET_STRING(iovec[2], header_pid);
 453         IOVEC_SET_STRING(iovec[3], buffer);
 454         IOVEC_SET_STRING(iovec[4], "\n");
 455
 456         if (writev(kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0)
 457                 return -errno;
 458
 459         return 1;
 460 }
 461
 462 static int log_do_header(
 463                 char *header,
 464                 size_t size,
 465                 int level,
 466                 int error,
 467                 const char *file, int line, const char *func,
 468                 const char *object_field, const char *object) {
 469
 470         snprintf(header, size,
 471                  "PRIORITY=%i\n"
 472                  "SYSLOG_FACILITY=%i\n"
 473                  "%s%s%s"
 474                  "%s%.*i%s"
 475                  "%s%s%s"
 476                  "%s%.*i%s"
 477                  "%s%s%s"
 478                  "SYSLOG_IDENTIFIER=%s\n",
 479                  LOG_PRI(level),
 480                  LOG_FAC(level),
 481                  isempty(file) ? "" : "CODE_FILE=",
 482                  isempty(file) ? "" : file,
 483                  isempty(file) ? "" : "\n",
 484                  line ? "CODE_LINE=" : "",
 485                  line ? 1 : 0, line, /* %.0d means no output too, special case for 0 */
 486                  line ? "\n" : "",
 487                  isempty(func) ? "" : "CODE_FUNCTION=",
 488                  isempty(func) ? "" : func,
 489                  isempty(func) ? "" : "\n",
 490                  error ? "ERRNO=" : "",
 491                  error ? 1 : 0, error,
 492                  error ? "\n" : "",
 493                  isempty(object) ? "" : object_field,
 494                  isempty(object) ? "" : object,
 495                  isempty(object) ? "" : "\n",
 496                  program_invocation_short_name);
 497
 498         return 0;
 499 }
 500
 501 static int write_to_journal(
 502                 int level,
 503                 int error,
 504                 const char*file,
 505                 int line,
 506                 const char *func,
 507                 const char *object_field,
 508                 const char *object,
 509                 const char *buffer) {
 510
 511         char header[LINE_MAX];
 512         struct iovec iovec[4] = {};
 513         struct msghdr mh = {};
 514
 515         if (journal_fd < 0)
 516                 return 0;
 517
 518         log_do_header(header, sizeof(header), level, error, file, line, func, object_field, object);
 519
 520         IOVEC_SET_STRING(iovec[0], header);
 521         IOVEC_SET_STRING(iovec[1], "MESSAGE=");
 522         IOVEC_SET_STRING(iovec[2], buffer);
 523         IOVEC_SET_STRING(iovec[3], "\n");
 524
 525         mh.msg_iov = iovec;
 526         mh.msg_iovlen = ELEMENTSOF(iovec);
 527
 528         if (sendmsg(journal_fd, &mh, MSG_NOSIGNAL) < 0)
 529                 return -errno;
 530
 531         return 1;
 532 }
 533
 534 static int log_dispatch(
 535                 int level,
 536                 int error,
 537                 const char *file,
 538                 int line,
 539                 const char *func,
 540                 const char *object_field,
 541                 const char *object,
 542                 char *buffer) {
 543
 544         assert(buffer);
 545
 546         if (log_target == LOG_TARGET_NULL)
 547                 return -error;
 548
 549         /* Patch in LOG_DAEMON facility if necessary */
 550         if ((level & LOG_FACMASK) == 0)
 551                 level = log_facility | LOG_PRI(level);
 552
 553         if (error < 0)
 554                 error = -error;
 555
 556         do {
 557                 char *e;
 558                 int k = 0;
 559
 560                 buffer += strspn(buffer, NEWLINE);
 561
 562                 if (buffer[0] == 0)
 563                         break;
 564
 565                 if ((e = strpbrk(buffer, NEWLINE)))
 566                         *(e++) = 0;
 567
 568                 if (log_target == LOG_TARGET_AUTO ||
 569                     log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
 570                     log_target == LOG_TARGET_JOURNAL) {
 571
 572                         k = write_to_journal(level, error, file, line, func, object_field, object, buffer);
 573                         if (k < 0) {
 574                                 if (k != -EAGAIN)
 575                                         log_close_journal();
 576                                 log_open_kmsg();
 577                         }
 578                 }
 579
 580                 if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
 581                     log_target == LOG_TARGET_SYSLOG) {
 582
 583                         k = write_to_syslog(level, error, file, line, func, object_field, object, buffer);
 584                         if (k < 0) {
 585                                 if (k != -EAGAIN)
 586                                         log_close_syslog();
 587                                 log_open_kmsg();
 588                         }
 589                 }
 590
 591                 if (k <= 0 &&
 592                     (log_target == LOG_TARGET_AUTO ||
 593                      log_target == LOG_TARGET_SAFE ||
 594                      log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
 595                      log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
 596                      log_target == LOG_TARGET_KMSG)) {
 597
 598                         k = write_to_kmsg(level, error, file, line, func, object_field, object, buffer);
 599                         if (k < 0) {
 600                                 log_close_kmsg();
 601                                 log_open_console();
 602                         }
 603                 }
 604
 605                 if (k <= 0)
 606                         (void) write_to_console(level, error, file, line, func, object_field, object, buffer);
 607
 608                 buffer = e;
 609         } while (buffer);
 610
 611         return -error;
 612 }
 613
 614 int log_dump_internal(
 615         int level,
 616         int error,
 617         const char *file,
 618         int line,
 619         const char *func,
 620         char *buffer) {
 621
 622         PROTECT_ERRNO;
 623
 624         /* This modifies the buffer... */
 625
 626         if (error < 0)
 627                 error = -error;
 628
 629         if (_likely_(LOG_PRI(level) > log_max_level))
 630                 return -error;
 631
 632         return log_dispatch(level, error, file, line, func, NULL, NULL, buffer);
 633 }
 634
 635 int log_internalv(
 636                 int level,
 637                 int error,
 638                 const char*file,
 639                 int line,
 640                 const char *func,
 641                 const char *format,
 642                 va_list ap) {
 643
 644         PROTECT_ERRNO;
 645         char buffer[LINE_MAX];
 646
 647         if (error < 0)
 648                 error = -error;
 649
 650         if (_likely_(LOG_PRI(level) > log_max_level))
 651                 return -error;
 652
 653         /* Make sure that %m maps to the specified error */
 654         if (error != 0)
 655                 errno = error;
 656
 657         vsnprintf(buffer, sizeof(buffer), format, ap);
 658
 659         return log_dispatch(level, error, file, line, func, NULL, NULL, buffer);
 660 }
 661
 662 int log_internal(
 663                 int level,
 664                 int error,
 665                 const char*file,
 666                 int line,
 667                 const char *func,
 668                 const char *format, ...) {
 669
 670         va_list ap;
 671         int r;
 672
 673         va_start(ap, format);
 674         r = log_internalv(level, error, file, line, func, format, ap);
 675         va_end(ap);
 676
 677         return r;
 678 }
 679
 680 int log_object_internalv(
 681                 int level,
 682                 int error,
 683                 const char*file,
 684                 int line,
 685                 const char *func,
 686                 const char *object_field,
 687                 const char *object,
 688                 const char *format,
 689                 va_list ap) {
 690
 691         PROTECT_ERRNO;
 692         char buffer[LINE_MAX];
 693
 694         if (error < 0)
 695                 error = -error;
 696
 697         if (_likely_(LOG_PRI(level) > log_max_level))
 698                 return -error;
 699
 700         /* Make sure that %m maps to the specified error */
 701         if (error != 0)
 702                 errno = error;
 703
 704         vsnprintf(buffer, sizeof(buffer), format, ap);
 705
 706         return log_dispatch(level, error, file, line, func, object_field, object, buffer);
 707 }
 708
 709 int log_object_internal(
 710                 int level,
 711                 int error,
 712                 const char*file,
 713                 int line,
 714                 const char *func,
 715                 const char *object_field,
 716                 const char *object,
 717                 const char *format, ...) {
 718
 719         va_list ap;
 720         int r;
 721
 722         va_start(ap, format);
 723         r = log_object_internalv(level, error, file, line, func, object_field, object, format, ap);
 724         va_end(ap);
 725
 726         return r;
 727 }
 728
 729 static void log_assert(
 730                 int level,
 731                 const char *text,
 732                 const char *file,
 733                 int line,
 734                 const char *func,
 735                 const char *format) {
 736
 737         static char buffer[LINE_MAX];
 738
 739         if (_likely_(LOG_PRI(level) > log_max_level))
 740                 return;
 741
 742         DISABLE_WARNING_FORMAT_NONLITERAL;
 743         snprintf(buffer, sizeof(buffer), format, text, file, line, func);
 744         REENABLE_WARNING;
 745
 746         log_abort_msg = buffer;
 747
 748         log_dispatch(level, 0, file, line, func, NULL, NULL, buffer);
 749 }
 750
 751 noreturn void log_assert_failed(const char *text, const char *file, int line, const char *func) {
 752         log_assert(LOG_CRIT, text, file, line, func, "Assertion '%s' failed at %s:%u, function %s(). Aborting.");
 753         abort();
 754 }
 755
 756 noreturn void log_assert_failed_unreachable(const char *text, const char *file, int line, const char *func) {
 757         log_assert(LOG_CRIT, text, file, line, func, "Code should not be reached '%s' at %s:%u, function %s(). Aborting.");
 758         abort();
 759 }
 760
 761 void log_assert_failed_return(const char *text, const char *file, int line, const char *func) {
 762         PROTECT_ERRNO;
 763         log_assert(LOG_DEBUG, text, file, line, func, "Assertion '%s' failed at %s:%u, function %s(). Ignoring.");
 764 }
 765
 766 int log_oom_internal(const char *file, int line, const char *func) {
 767         log_internal(LOG_ERR, ENOMEM, file, line, func, "Out of memory.");
 768         return -ENOMEM;
 769 }
 770
 771 int log_struct_internal(
 772                 int level,
 773                 int error,
 774                 const char *file,
 775                 int line,
 776                 const char *func,
 777                 const char *format, ...) {
 778
 779         char buf[LINE_MAX];
 780         bool found = false;
 781         PROTECT_ERRNO;
 782         va_list ap;
 783
 784         if (error < 0)
 785                 error = -error;
 786
 787         if (_likely_(LOG_PRI(level) > log_max_level))
 788                 return -error;
 789
 790         if (log_target == LOG_TARGET_NULL)
 791                 return -error;
 792
 793         if ((level & LOG_FACMASK) == 0)
 794                 level = log_facility | LOG_PRI(level);
 795
 796         if ((log_target == LOG_TARGET_AUTO ||
 797              log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
 798              log_target == LOG_TARGET_JOURNAL) &&
 799             journal_fd >= 0) {
 800                 char header[LINE_MAX];
 801                 struct iovec iovec[17] = {};
 802                 unsigned n = 0, i;
 803                 struct msghdr mh = {
 804                         .msg_iov = iovec,
 805                 };
 806                 static const char nl = '\n';
 807                 bool fallback = false;
 808
 809                 /* If the journal is available do structured logging */
 810                 log_do_header(header, sizeof(header), level, error, file, line, func, NULL, NULL);
 811                 IOVEC_SET_STRING(iovec[n++], header);
 812
 813                 va_start(ap, format);
 814                 while (format && n + 1 < ELEMENTSOF(iovec)) {
 815                         va_list aq;
 816                         char *m;
 817
 818                         /* We need to copy the va_list structure,
 819                          * since vasprintf() leaves it afterwards at
 820                          * an undefined location */
 821
 822                         if (error != 0)
 823                                 errno = error;
 824
 825                         va_copy(aq, ap);
 826                         if (vasprintf(&m, format, aq) < 0) {
 827                                 va_end(aq);
 828                                 fallback = true;
 829                                 goto finish;
 830                         }
 831                         va_end(aq);
 832
 833                         /* Now, jump enough ahead, so that we point to
 834                          * the next format string */
 835                         VA_FORMAT_ADVANCE(format, ap);
 836
 837                         IOVEC_SET_STRING(iovec[n++], m);
 838
 839                         iovec[n].iov_base = (char*) &nl;
 840                         iovec[n].iov_len = 1;
 841                         n++;
 842
 843                         format = va_arg(ap, char *);
 844                 }
 845
 846                 mh.msg_iovlen = n;
 847
 848                 (void) sendmsg(journal_fd, &mh, MSG_NOSIGNAL);
 849
 850         finish:
 851                 va_end(ap);
 852                 for (i = 1; i < n; i += 2)
 853                         free(iovec[i].iov_base);
 854
 855                 if (!fallback)
 856                         return -error;
 857         }
 858
 859         /* Fallback if journal logging is not available or didn't work. */
 860
 861         va_start(ap, format);
 862         while (format) {
 863                 va_list aq;
 864
 865                 if (error != 0)
 866                         errno = error;
 867
 868                 va_copy(aq, ap);
 869                 vsnprintf(buf, sizeof(buf), format, aq);
 870                 va_end(aq);
 871
 872                 if (startswith(buf, "MESSAGE=")) {
 873                         found = true;
 874                         break;
 875                 }
 876
 877                 VA_FORMAT_ADVANCE(format, ap);
 878
 879                 format = va_arg(ap, char *);
 880         }
 881         va_end(ap);
 882
 883         if (!found)
 884                 return -error;
 885
 886         return log_dispatch(level, error, file, line, func, NULL, NULL, buf + 8);
 887 }
 888
 889 int log_set_target_from_string(const char *e) {
 890         LogTarget t;
 891
 892         t = log_target_from_string(e);
 893         if (t < 0)
 894                 return -EINVAL;
 895
 896         log_set_target(t);
 897         return 0;
 898 }
 899
 900 int log_set_max_level_from_string(const char *e) {
 901         int t;
 902
 903         t = log_level_from_string(e);
 904         if (t < 0)
 905                 return t;
 906
 907         log_set_max_level(t);
 908         return 0;
 909 }
 910
 911 static int parse_proc_cmdline_item(const char *key, const char *value) {
 912
 913         /*
 914          * The systemd.log_xyz= settings are parsed by all tools, and
 915          * so is "debug".
 916          *
 917          * However, "quiet" is only parsed by PID 1, and only turns of
 918          * status output to /dev/console, but does not alter the log
 919          * level.
 920          */
 921
 922         if (streq(key, "debug") && !value)
 923                 log_set_max_level(LOG_DEBUG);
 924
 925         else if (streq(key, "systemd.log_target") && value) {
 926
 927                 if (log_set_target_from_string(value) < 0)
 928                         log_warning("Failed to parse log target '%s'. Ignoring.", value);
 929
 930         } else if (streq(key, "systemd.log_level") && value) {
 931
 932                 if (log_set_max_level_from_string(value) < 0)
 933                         log_warning("Failed to parse log level '%s'. Ignoring.", value);
 934
 935         } else if (streq(key, "systemd.log_color") && value) {
 936
 937                 if (log_show_color_from_string(value) < 0)
 938                         log_warning("Failed to parse log color setting '%s'. Ignoring.", value);
 939
 940         } else if (streq(key, "systemd.log_location") && value) {
 941
 942                 if (log_show_location_from_string(value) < 0)
 943                         log_warning("Failed to parse log location setting '%s'. Ignoring.", value);
 944         }
 945
 946         return 0;
 947 }
 948
 949 void log_parse_environment(void) {
 950         const char *e;
 951
 952         (void) parse_proc_cmdline(parse_proc_cmdline_item);
 953
 954         e = secure_getenv("SYSTEMD_LOG_TARGET");
 955         if (e && log_set_target_from_string(e) < 0)
 956                 log_warning("Failed to parse log target '%s'. Ignoring.", e);
 957
 958         e = secure_getenv("SYSTEMD_LOG_LEVEL");
 959         if (e && log_set_max_level_from_string(e) < 0)
 960                 log_warning("Failed to parse log level '%s'. Ignoring.", e);
 961
 962         e = secure_getenv("SYSTEMD_LOG_COLOR");
 963         if (e && log_show_color_from_string(e) < 0)
 964                 log_warning("Failed to parse bool '%s'. Ignoring.", e);
 965
 966         e = secure_getenv("SYSTEMD_LOG_LOCATION");
 967         if (e && log_show_location_from_string(e) < 0)
 968                 log_warning("Failed to parse bool '%s'. Ignoring.", e);
 969 }
 970
 971 LogTarget log_get_target(void) {
 972         return log_target;
 973 }
 974
 975 int log_get_max_level(void) {
 976         return log_max_level;
 977 }
 978
 979 void log_show_color(bool b) {
 980         show_color = b;
 981 }
 982
 983 bool log_get_show_color(void) {
 984         return show_color;
 985 }
 986
 987 void log_show_location(bool b) {
 988         show_location = b;
 989 }
 990
 991 bool log_get_show_location(void) {
 992         return show_location;
 993 }
 994
 995 int log_show_color_from_string(const char *e) {
 996         int t;
 997
 998         t = parse_boolean(e);
 999         if (t < 0)
1000                 return t;
1001
1002         log_show_color(t);
1003         return 0;
1004 }
1005
1006 int log_show_location_from_string(const char *e) {
1007         int t;
1008
1009         t = parse_boolean(e);
1010         if (t < 0)
1011                 return t;
1012
1013         log_show_location(t);
1014         return 0;
1015 }
1016
1017 bool log_on_console(void) {
1018         if (log_target == LOG_TARGET_CONSOLE ||
1019             log_target == LOG_TARGET_CONSOLE_PREFIXED)
1020                 return true;
1021
1022         return syslog_fd < 0 && kmsg_fd < 0 && journal_fd < 0;
1023 }
1024
1025 static const char *const log_target_table[_LOG_TARGET_MAX] = {
1026         [LOG_TARGET_CONSOLE] = "console",
1027         [LOG_TARGET_CONSOLE_PREFIXED] = "console-prefixed",
1028         [LOG_TARGET_KMSG] = "kmsg",
1029         [LOG_TARGET_JOURNAL] = "journal",
1030         [LOG_TARGET_JOURNAL_OR_KMSG] = "journal-or-kmsg",
1031         [LOG_TARGET_SYSLOG] = "syslog",
1032         [LOG_TARGET_SYSLOG_OR_KMSG] = "syslog-or-kmsg",
1033         [LOG_TARGET_AUTO] = "auto",
1034         [LOG_TARGET_SAFE] = "safe",
1035         [LOG_TARGET_NULL] = "null"
1036 };
1037
1038 DEFINE_STRING_TABLE_LOOKUP(log_target, LogTarget);
1039
1040 void log_received_signal(int level, const struct signalfd_siginfo *si) {
1041         if (si->ssi_pid > 0) {
1042                 _cleanup_free_ char *p = NULL;
1043
1044                 get_process_comm(si->ssi_pid, &p);
1045
1046                 log_full(level,
1047                          "Received SIG%s from PID %"PRIu32" (%s).",
1048                          signal_to_string(si->ssi_signo),
1049                          si->ssi_pid, strna(p));
1050         } else
1051                 log_full(level,
1052                          "Received SIG%s.",
1053                          signal_to_string(si->ssi_signo));
1054
1055 }
1056
1057 void log_set_upgrade_syslog_to_journal(bool b) {
1058         upgrade_syslog_to_journal = b;
1059 }