src/basic/log.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2010 Lennart Poettering
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <errno.h>
  21 #include <fcntl.h>
  22 #include <inttypes.h>
  23 #include <limits.h>
  24 #include <stdarg.h>
  25 #include <stddef.h>
  26 #include <stdio.h>
  27 #include <string.h>
  28 #include <sys/signalfd.h>
  29 #include <sys/socket.h>
  30 #include <sys/time.h>
  31 #include <sys/uio.h>
  32 #include <sys/un.h>
  33 #include <time.h>
  34 #include <unistd.h>
  35
  36 #include "sd-messages.h"
  37
  38 #include "alloc-util.h"
  39 #include "fd-util.h"
  40 #include "formats-util.h"
  41 #include "io-util.h"
  42 #include "log.h"
  43 #include "macro.h"
  44 #include "missing.h"
  45 #include "parse-util.h"
  46 #include "proc-cmdline.h"
  47 #include "process-util.h"
  48 #include "signal-util.h"
  49 #include "socket-util.h"
  50 #include "stdio-util.h"
  51 #include "string-table.h"
  52 #include "string-util.h"
  53 #include "syslog-util.h"
  54 #include "terminal-util.h"
  55 #include "time-util.h"
  56 #include "util.h"
  57
  58 #define SNDBUF_SIZE (8*1024*1024)
  59
  60 static LogTarget log_target = LOG_TARGET_CONSOLE;
  61 static int log_max_level = LOG_INFO;
  62 static int log_facility = LOG_DAEMON;
  63
  64 static int console_fd = STDERR_FILENO;
  65 static int syslog_fd = -1;
  66 static int kmsg_fd = -1;
  67 static int journal_fd = -1;
  68
  69 static bool syslog_is_stream = false;
  70
  71 static bool show_color = false;
  72 static bool show_location = false;
  73
  74 static bool upgrade_syslog_to_journal = false;
  75
  76 /* Akin to glibc's __abort_msg; which is private and we hence cannot
  77  * use here. */
  78 static char *log_abort_msg = NULL;
  79
  80 void log_close_console(void) {
  81
  82         if (console_fd < 0)
  83                 return;
  84
  85         if (getpid() == 1) {
  86                 if (console_fd >= 3)
  87                         safe_close(console_fd);
  88
  89                 console_fd = -1;
  90         }
  91 }
  92
  93 static int log_open_console(void) {
  94
  95         if (console_fd >= 0)
  96                 return 0;
  97
  98         if (getpid() == 1) {
  99                 console_fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC);
 100                 if (console_fd < 0)
 101                         return console_fd;
 102         } else
 103                 console_fd = STDERR_FILENO;
 104
 105         return 0;
 106 }
 107
 108 void log_close_kmsg(void) {
 109         kmsg_fd = safe_close(kmsg_fd);
 110 }
 111
 112 static int log_open_kmsg(void) {
 113
 114         if (kmsg_fd >= 0)
 115                 return 0;
 116
 117         kmsg_fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC);
 118         if (kmsg_fd < 0)
 119                 return -errno;
 120
 121         return 0;
 122 }
 123
 124 void log_close_syslog(void) {
 125         syslog_fd = safe_close(syslog_fd);
 126 }
 127
 128 static int create_log_socket(int type) {
 129         struct timeval tv;
 130         int fd;
 131
 132         fd = socket(AF_UNIX, type|SOCK_CLOEXEC, 0);
 133         if (fd < 0)
 134                 return -errno;
 135
 136         (void) fd_inc_sndbuf(fd, SNDBUF_SIZE);
 137
 138         /* We need a blocking fd here since we'd otherwise lose
 139         messages way too early. However, let's not hang forever in the
 140         unlikely case of a deadlock. */
 141         if (getpid() == 1)
 142                 timeval_store(&tv, 10 * USEC_PER_MSEC);
 143         else
 144                 timeval_store(&tv, 10 * USEC_PER_SEC);
 145         (void) setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv));
 146
 147         return fd;
 148 }
 149
 150 static int log_open_syslog(void) {
 151
 152         static const union sockaddr_union sa = {
 153                 .un.sun_family = AF_UNIX,
 154                 .un.sun_path = "/dev/log",
 155         };
 156
 157         int r;
 158
 159         if (syslog_fd >= 0)
 160                 return 0;
 161
 162         syslog_fd = create_log_socket(SOCK_DGRAM);
 163         if (syslog_fd < 0) {
 164                 r = syslog_fd;
 165                 goto fail;
 166         }
 167
 168         if (connect(syslog_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) {
 169                 safe_close(syslog_fd);
 170
 171                 /* Some legacy syslog systems still use stream
 172                  * sockets. They really shouldn't. But what can we
 173                  * do... */
 174                 syslog_fd = create_log_socket(SOCK_STREAM);
 175                 if (syslog_fd < 0) {
 176                         r = syslog_fd;
 177                         goto fail;
 178                 }
 179
 180                 if (connect(syslog_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) {
 181                         r = -errno;
 182                         goto fail;
 183                 }
 184
 185                 syslog_is_stream = true;
 186         } else
 187                 syslog_is_stream = false;
 188
 189         return 0;
 190
 191 fail:
 192         log_close_syslog();
 193         return r;
 194 }
 195
 196 void log_close_journal(void) {
 197         journal_fd = safe_close(journal_fd);
 198 }
 199
 200 static int log_open_journal(void) {
 201
 202         static const union sockaddr_union sa = {
 203                 .un.sun_family = AF_UNIX,
 204                 .un.sun_path = "/run/systemd/journal/socket",
 205         };
 206
 207         int r;
 208
 209         if (journal_fd >= 0)
 210                 return 0;
 211
 212         journal_fd = create_log_socket(SOCK_DGRAM);
 213         if (journal_fd < 0) {
 214                 r = journal_fd;
 215                 goto fail;
 216         }
 217
 218         if (connect(journal_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) {
 219                 r = -errno;
 220                 goto fail;
 221         }
 222
 223         return 0;
 224
 225 fail:
 226         log_close_journal();
 227         return r;
 228 }
 229
 230 int log_open(void) {
 231         int r;
 232
 233         /* If we don't use the console we close it here, to not get
 234          * killed by SAK. If we don't use syslog we close it here so
 235          * that we are not confused by somebody deleting the socket in
 236          * the fs. If we don't use /dev/kmsg we still keep it open,
 237          * because there is no reason to close it. */
 238
 239         if (log_target == LOG_TARGET_NULL) {
 240                 log_close_journal();
 241                 log_close_syslog();
 242                 log_close_console();
 243                 return 0;
 244         }
 245
 246         if ((log_target != LOG_TARGET_AUTO && log_target != LOG_TARGET_SAFE) ||
 247             getpid() == 1 ||
 248             isatty(STDERR_FILENO) <= 0) {
 249
 250                 if (log_target == LOG_TARGET_AUTO ||
 251                     log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
 252                     log_target == LOG_TARGET_JOURNAL) {
 253                         r = log_open_journal();
 254                         if (r >= 0) {
 255                                 log_close_syslog();
 256                                 log_close_console();
 257                                 return r;
 258                         }
 259                 }
 260
 261                 if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
 262                     log_target == LOG_TARGET_SYSLOG) {
 263                         r = log_open_syslog();
 264                         if (r >= 0) {
 265                                 log_close_journal();
 266                                 log_close_console();
 267                                 return r;
 268                         }
 269                 }
 270
 271                 if (log_target == LOG_TARGET_AUTO ||
 272                     log_target == LOG_TARGET_SAFE ||
 273                     log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
 274                     log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
 275                     log_target == LOG_TARGET_KMSG) {
 276                         r = log_open_kmsg();
 277                         if (r >= 0) {
 278                                 log_close_journal();
 279                                 log_close_syslog();
 280                                 log_close_console();
 281                                 return r;
 282                         }
 283                 }
 284         }
 285
 286         log_close_journal();
 287         log_close_syslog();
 288
 289         return log_open_console();
 290 }
 291
 292 void log_set_target(LogTarget target) {
 293         assert(target >= 0);
 294         assert(target < _LOG_TARGET_MAX);
 295
 296         if (upgrade_syslog_to_journal) {
 297                 if (target == LOG_TARGET_SYSLOG)
 298                         target = LOG_TARGET_JOURNAL;
 299                 else if (target == LOG_TARGET_SYSLOG_OR_KMSG)
 300                         target = LOG_TARGET_JOURNAL_OR_KMSG;
 301         }
 302
 303         log_target = target;
 304 }
 305
 306 void log_close(void) {
 307         log_close_journal();
 308         log_close_syslog();
 309         log_close_kmsg();
 310         log_close_console();
 311 }
 312
 313 void log_forget_fds(void) {
 314         console_fd = kmsg_fd = syslog_fd = journal_fd = -1;
 315 }
 316
 317 void log_set_max_level(int level) {
 318         assert((level & LOG_PRIMASK) == level);
 319
 320         log_max_level = level;
 321 }
 322
 323 void log_set_facility(int facility) {
 324         log_facility = facility;
 325 }
 326
 327 static int write_to_console(
 328                 int level,
 329                 int error,
 330                 const char *file,
 331                 int line,
 332                 const char *func,
 333                 const char *buffer) {
 334
 335         char location[256], prefix[1 + DECIMAL_STR_MAX(int) + 2];
 336         struct iovec iovec[6] = {};
 337         unsigned n = 0;
 338         bool highlight;
 339
 340         if (console_fd < 0)
 341                 return 0;
 342
 343         if (log_target == LOG_TARGET_CONSOLE_PREFIXED) {
 344                 xsprintf(prefix, "<%i>", level);
 345                 IOVEC_SET_STRING(iovec[n++], prefix);
 346         }
 347
 348         highlight = LOG_PRI(level) <= LOG_ERR && show_color;
 349
 350         if (show_location) {
 351                 snprintf(location, sizeof(location), "(%s:%i) ", file, line);
 352                 IOVEC_SET_STRING(iovec[n++], location);
 353         }
 354
 355         if (highlight)
 356                 IOVEC_SET_STRING(iovec[n++], ANSI_HIGHLIGHT_RED);
 357         IOVEC_SET_STRING(iovec[n++], buffer);
 358         if (highlight)
 359                 IOVEC_SET_STRING(iovec[n++], ANSI_NORMAL);
 360         IOVEC_SET_STRING(iovec[n++], "\n");
 361
 362         if (writev(console_fd, iovec, n) < 0) {
 363
 364                 if (errno == EIO && getpid() == 1) {
 365
 366                         /* If somebody tried to kick us from our
 367                          * console tty (via vhangup() or suchlike),
 368                          * try to reconnect */
 369
 370                         log_close_console();
 371                         log_open_console();
 372
 373                         if (console_fd < 0)
 374                                 return 0;
 375
 376                         if (writev(console_fd, iovec, n) < 0)
 377                                 return -errno;
 378                 } else
 379                         return -errno;
 380         }
 381
 382         return 1;
 383 }
 384
 385 static int write_to_syslog(
 386                 int level,
 387                 int error,
 388                 const char *file,
 389                 int line,
 390                 const char *func,
 391                 const char *buffer) {
 392
 393         char header_priority[2 + DECIMAL_STR_MAX(int) + 1],
 394              header_time[64],
 395              header_pid[4 + DECIMAL_STR_MAX(pid_t) + 1];
 396         struct iovec iovec[5] = {};
 397         struct msghdr msghdr = {
 398                 .msg_iov = iovec,
 399                 .msg_iovlen = ELEMENTSOF(iovec),
 400         };
 401         time_t t;
 402         struct tm *tm;
 403
 404         if (syslog_fd < 0)
 405                 return 0;
 406
 407         xsprintf(header_priority, "<%i>", level);
 408
 409         t = (time_t) (now(CLOCK_REALTIME) / USEC_PER_SEC);
 410         tm = localtime(&t);
 411         if (!tm)
 412                 return -EINVAL;
 413
 414         if (strftime(header_time, sizeof(header_time), "%h %e %T ", tm) <= 0)
 415                 return -EINVAL;
 416
 417         xsprintf(header_pid, "["PID_FMT"]: ", getpid());
 418
 419         IOVEC_SET_STRING(iovec[0], header_priority);
 420         IOVEC_SET_STRING(iovec[1], header_time);
 421         IOVEC_SET_STRING(iovec[2], program_invocation_short_name);
 422         IOVEC_SET_STRING(iovec[3], header_pid);
 423         IOVEC_SET_STRING(iovec[4], buffer);
 424
 425         /* When using syslog via SOCK_STREAM separate the messages by NUL chars */
 426         if (syslog_is_stream)
 427                 iovec[4].iov_len++;
 428
 429         for (;;) {
 430                 ssize_t n;
 431
 432                 n = sendmsg(syslog_fd, &msghdr, MSG_NOSIGNAL);
 433                 if (n < 0)
 434                         return -errno;
 435
 436                 if (!syslog_is_stream ||
 437                     (size_t) n >= IOVEC_TOTAL_SIZE(iovec, ELEMENTSOF(iovec)))
 438                         break;
 439
 440                 IOVEC_INCREMENT(iovec, ELEMENTSOF(iovec), n);
 441         }
 442
 443         return 1;
 444 }
 445
 446 static int write_to_kmsg(
 447                 int level,
 448                 int error,
 449                 const char *file,
 450                 int line,
 451                 const char *func,
 452                 const char *buffer) {
 453
 454         char header_priority[2 + DECIMAL_STR_MAX(int) + 1],
 455              header_pid[4 + DECIMAL_STR_MAX(pid_t) + 1];
 456         struct iovec iovec[5] = {};
 457
 458         if (kmsg_fd < 0)
 459                 return 0;
 460
 461         xsprintf(header_priority, "<%i>", level);
 462         xsprintf(header_pid, "["PID_FMT"]: ", getpid());
 463
 464         IOVEC_SET_STRING(iovec[0], header_priority);
 465         IOVEC_SET_STRING(iovec[1], program_invocation_short_name);
 466         IOVEC_SET_STRING(iovec[2], header_pid);
 467         IOVEC_SET_STRING(iovec[3], buffer);
 468         IOVEC_SET_STRING(iovec[4], "\n");
 469
 470         if (writev(kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0)
 471                 return -errno;
 472
 473         return 1;
 474 }
 475
 476 static int log_do_header(
 477                 char *header,
 478                 size_t size,
 479                 int level,
 480                 int error,
 481                 const char *file, int line, const char *func,
 482                 const char *object_field, const char *object,
 483                 const char *extra_field, const char *extra) {
 484
 485         snprintf(header, size,
 486                  "PRIORITY=%i\n"
 487                  "SYSLOG_FACILITY=%i\n"
 488                  "%s%s%s"
 489                  "%s%.*i%s"
 490                  "%s%s%s"
 491                  "%s%.*i%s"
 492                  "%s%s%s"
 493                  "%s%s%s"
 494                  "SYSLOG_IDENTIFIER=%s\n",
 495                  LOG_PRI(level),
 496                  LOG_FAC(level),
 497                  isempty(file) ? "" : "CODE_FILE=",
 498                  isempty(file) ? "" : file,
 499                  isempty(file) ? "" : "\n",
 500                  line ? "CODE_LINE=" : "",
 501                  line ? 1 : 0, line, /* %.0d means no output too, special case for 0 */
 502                  line ? "\n" : "",
 503                  isempty(func) ? "" : "CODE_FUNCTION=",
 504                  isempty(func) ? "" : func,
 505                  isempty(func) ? "" : "\n",
 506                  error ? "ERRNO=" : "",
 507                  error ? 1 : 0, error,
 508                  error ? "\n" : "",
 509                  isempty(object) ? "" : object_field,
 510                  isempty(object) ? "" : object,
 511                  isempty(object) ? "" : "\n",
 512                  isempty(extra) ? "" : extra_field,
 513                  isempty(extra) ? "" : extra,
 514                  isempty(extra) ? "" : "\n",
 515                  program_invocation_short_name);
 516
 517         return 0;
 518 }
 519
 520 static int write_to_journal(
 521                 int level,
 522                 int error,
 523                 const char *file,
 524                 int line,
 525                 const char *func,
 526                 const char *object_field,
 527                 const char *object,
 528                 const char *extra_field,
 529                 const char *extra,
 530                 const char *buffer) {
 531
 532         char header[LINE_MAX];
 533         struct iovec iovec[4] = {};
 534         struct msghdr mh = {};
 535
 536         if (journal_fd < 0)
 537                 return 0;
 538
 539         log_do_header(header, sizeof(header), level, error, file, line, func, object_field, object, extra_field, extra);
 540
 541         IOVEC_SET_STRING(iovec[0], header);
 542         IOVEC_SET_STRING(iovec[1], "MESSAGE=");
 543         IOVEC_SET_STRING(iovec[2], buffer);
 544         IOVEC_SET_STRING(iovec[3], "\n");
 545
 546         mh.msg_iov = iovec;
 547         mh.msg_iovlen = ELEMENTSOF(iovec);
 548
 549         if (sendmsg(journal_fd, &mh, MSG_NOSIGNAL) < 0)
 550                 return -errno;
 551
 552         return 1;
 553 }
 554
 555 static int log_dispatch(
 556                 int level,
 557                 int error,
 558                 const char *file,
 559                 int line,
 560                 const char *func,
 561                 const char *object_field,
 562                 const char *object,
 563                 const char *extra,
 564                 const char *extra_field,
 565                 char *buffer) {
 566
 567         assert(buffer);
 568
 569         if (error < 0)
 570                 error = -error;
 571
 572         if (log_target == LOG_TARGET_NULL)
 573                 return -error;
 574
 575         /* Patch in LOG_DAEMON facility if necessary */
 576         if ((level & LOG_FACMASK) == 0)
 577                 level = log_facility | LOG_PRI(level);
 578
 579         do {
 580                 char *e;
 581                 int k = 0;
 582
 583                 buffer += strspn(buffer, NEWLINE);
 584
 585                 if (buffer[0] == 0)
 586                         break;
 587
 588                 if ((e = strpbrk(buffer, NEWLINE)))
 589                         *(e++) = 0;
 590
 591                 if (log_target == LOG_TARGET_AUTO ||
 592                     log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
 593                     log_target == LOG_TARGET_JOURNAL) {
 594
 595                         k = write_to_journal(level, error, file, line, func, object_field, object, extra_field, extra, buffer);
 596                         if (k < 0) {
 597                                 if (k != -EAGAIN)
 598                                         log_close_journal();
 599                                 log_open_kmsg();
 600                         }
 601                 }
 602
 603                 if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
 604                     log_target == LOG_TARGET_SYSLOG) {
 605
 606                         k = write_to_syslog(level, error, file, line, func, buffer);
 607                         if (k < 0) {
 608                                 if (k != -EAGAIN)
 609                                         log_close_syslog();
 610                                 log_open_kmsg();
 611                         }
 612                 }
 613
 614                 if (k <= 0 &&
 615                     (log_target == LOG_TARGET_AUTO ||
 616                      log_target == LOG_TARGET_SAFE ||
 617                      log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
 618                      log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
 619                      log_target == LOG_TARGET_KMSG)) {
 620
 621                         k = write_to_kmsg(level, error, file, line, func, buffer);
 622                         if (k < 0) {
 623                                 log_close_kmsg();
 624                                 log_open_console();
 625                         }
 626                 }
 627
 628                 if (k <= 0)
 629                         (void) write_to_console(level, error, file, line, func, buffer);
 630
 631                 buffer = e;
 632         } while (buffer);
 633
 634         return -error;
 635 }
 636
 637 int log_dump_internal(
 638         int level,
 639         int error,
 640         const char *file,
 641         int line,
 642         const char *func,
 643         char *buffer) {
 644
 645         PROTECT_ERRNO;
 646
 647         /* This modifies the buffer... */
 648
 649         if (error < 0)
 650                 error = -error;
 651
 652         if (_likely_(LOG_PRI(level) > log_max_level))
 653                 return -error;
 654
 655         return log_dispatch(level, error, file, line, func, NULL, NULL, NULL, NULL, buffer);
 656 }
 657
 658 int log_internalv(
 659                 int level,
 660                 int error,
 661                 const char *file,
 662                 int line,
 663                 const char *func,
 664                 const char *format,
 665                 va_list ap) {
 666
 667         PROTECT_ERRNO;
 668         char buffer[LINE_MAX];
 669
 670         if (error < 0)
 671                 error = -error;
 672
 673         if (_likely_(LOG_PRI(level) > log_max_level))
 674                 return -error;
 675
 676         /* Make sure that %m maps to the specified error */
 677         if (error != 0)
 678                 errno = error;
 679
 680         vsnprintf(buffer, sizeof(buffer), format, ap);
 681
 682         return log_dispatch(level, error, file, line, func, NULL, NULL, NULL, NULL, buffer);
 683 }
 684
 685 int log_internal(
 686                 int level,
 687                 int error,
 688                 const char *file,
 689                 int line,
 690                 const char *func,
 691                 const char *format, ...) {
 692
 693         va_list ap;
 694         int r;
 695
 696         va_start(ap, format);
 697         r = log_internalv(level, error, file, line, func, format, ap);
 698         va_end(ap);
 699
 700         return r;
 701 }
 702
 703 int log_object_internalv(
 704                 int level,
 705                 int error,
 706                 const char *file,
 707                 int line,
 708                 const char *func,
 709                 const char *object_field,
 710                 const char *object,
 711                 const char *extra_field,
 712                 const char *extra,
 713                 const char *format,
 714                 va_list ap) {
 715
 716         PROTECT_ERRNO;
 717         char *buffer, *b;
 718         size_t l;
 719
 720         if (error < 0)
 721                 error = -error;
 722
 723         if (_likely_(LOG_PRI(level) > log_max_level))
 724                 return -error;
 725
 726         /* Make sure that %m maps to the specified error */
 727         if (error != 0)
 728                 errno = error;
 729
 730         /* Prepend the object name before the message */
 731         if (object) {
 732                 size_t n;
 733
 734                 n = strlen(object);
 735                 l = n + 2 + LINE_MAX;
 736
 737                 buffer = newa(char, l);
 738                 b = stpcpy(stpcpy(buffer, object), ": ");
 739         } else {
 740                 l = LINE_MAX;
 741                 b = buffer = newa(char, l);
 742         }
 743
 744         vsnprintf(b, l, format, ap);
 745
 746         return log_dispatch(level, error, file, line, func, object_field, object, extra_field, extra, buffer);
 747 }
 748
 749 int log_object_internal(
 750                 int level,
 751                 int error,
 752                 const char *file,
 753                 int line,
 754                 const char *func,
 755                 const char *object_field,
 756                 const char *object,
 757                 const char *extra_field,
 758                 const char *extra,
 759                 const char *format, ...) {
 760
 761         va_list ap;
 762         int r;
 763
 764         va_start(ap, format);
 765         r = log_object_internalv(level, error, file, line, func, object_field, object, extra_field, extra, format, ap);
 766         va_end(ap);
 767
 768         return r;
 769 }
 770
 771 static void log_assert(
 772                 int level,
 773                 const char *text,
 774                 const char *file,
 775                 int line,
 776                 const char *func,
 777                 const char *format) {
 778
 779         static char buffer[LINE_MAX];
 780
 781         if (_likely_(LOG_PRI(level) > log_max_level))
 782                 return;
 783
 784         DISABLE_WARNING_FORMAT_NONLITERAL;
 785         xsprintf(buffer, format, text, file, line, func);
 786         REENABLE_WARNING;
 787
 788         log_abort_msg = buffer;
 789
 790         log_dispatch(level, 0, file, line, func, NULL, NULL, NULL, NULL, buffer);
 791 }
 792
 793 noreturn void log_assert_failed(const char *text, const char *file, int line, const char *func) {
 794         log_assert(LOG_CRIT, text, file, line, func, "Assertion '%s' failed at %s:%u, function %s(). Aborting.");
 795         abort();
 796 }
 797
 798 noreturn void log_assert_failed_unreachable(const char *text, const char *file, int line, const char *func) {
 799         log_assert(LOG_CRIT, text, file, line, func, "Code should not be reached '%s' at %s:%u, function %s(). Aborting.");
 800         abort();
 801 }
 802
 803 void log_assert_failed_return(const char *text, const char *file, int line, const char *func) {
 804         PROTECT_ERRNO;
 805         log_assert(LOG_DEBUG, text, file, line, func, "Assertion '%s' failed at %s:%u, function %s(). Ignoring.");
 806 }
 807
 808 int log_oom_internal(const char *file, int line, const char *func) {
 809         log_internal(LOG_ERR, ENOMEM, file, line, func, "Out of memory.");
 810         return -ENOMEM;
 811 }
 812
 813 int log_format_iovec(
 814                 struct iovec *iovec,
 815                 unsigned iovec_len,
 816                 unsigned *n,
 817                 bool newline_separator,
 818                 int error,
 819                 const char *format,
 820                 va_list ap) {
 821
 822         static const char nl = '\n';
 823
 824         while (format && *n + 1 < iovec_len) {
 825                 va_list aq;
 826                 char *m;
 827                 int r;
 828
 829                 /* We need to copy the va_list structure,
 830                  * since vasprintf() leaves it afterwards at
 831                  * an undefined location */
 832
 833                 if (error != 0)
 834                         errno = error;
 835
 836                 va_copy(aq, ap);
 837                 r = vasprintf(&m, format, aq);
 838                 va_end(aq);
 839                 if (r < 0)
 840                         return -EINVAL;
 841
 842                 /* Now, jump enough ahead, so that we point to
 843                  * the next format string */
 844                 VA_FORMAT_ADVANCE(format, ap);
 845
 846                 IOVEC_SET_STRING(iovec[(*n)++], m);
 847
 848                 if (newline_separator) {
 849                         iovec[*n].iov_base = (char*) &nl;
 850                         iovec[*n].iov_len = 1;
 851                         (*n)++;
 852                 }
 853
 854                 format = va_arg(ap, char *);
 855         }
 856         return 0;
 857 }
 858
 859 int log_struct_internal(
 860                 int level,
 861                 int error,
 862                 const char *file,
 863                 int line,
 864                 const char *func,
 865                 const char *format, ...) {
 866
 867         char buf[LINE_MAX];
 868         bool found = false;
 869         PROTECT_ERRNO;
 870         va_list ap;
 871
 872         if (error < 0)
 873                 error = -error;
 874
 875         if (_likely_(LOG_PRI(level) > log_max_level))
 876                 return -error;
 877
 878         if (log_target == LOG_TARGET_NULL)
 879                 return -error;
 880
 881         if ((level & LOG_FACMASK) == 0)
 882                 level = log_facility | LOG_PRI(level);
 883
 884         if ((log_target == LOG_TARGET_AUTO ||
 885              log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
 886              log_target == LOG_TARGET_JOURNAL) &&
 887             journal_fd >= 0) {
 888                 char header[LINE_MAX];
 889                 struct iovec iovec[17] = {};
 890                 unsigned n = 0, i;
 891                 int r;
 892                 struct msghdr mh = {
 893                         .msg_iov = iovec,
 894                 };
 895                 bool fallback = false;
 896
 897                 /* If the journal is available do structured logging */
 898                 log_do_header(header, sizeof(header), level, error, file, line, func, NULL, NULL, NULL, NULL);
 899                 IOVEC_SET_STRING(iovec[n++], header);
 900
 901                 va_start(ap, format);
 902                 r = log_format_iovec(iovec, ELEMENTSOF(iovec), &n, true, error, format, ap);
 903                 if (r < 0)
 904                         fallback = true;
 905                 else {
 906                         mh.msg_iovlen = n;
 907                         (void) sendmsg(journal_fd, &mh, MSG_NOSIGNAL);
 908                 }
 909
 910                 va_end(ap);
 911                 for (i = 1; i < n; i += 2)
 912                         free(iovec[i].iov_base);
 913
 914                 if (!fallback)
 915                         return -error;
 916         }
 917
 918         /* Fallback if journal logging is not available or didn't work. */
 919
 920         va_start(ap, format);
 921         while (format) {
 922                 va_list aq;
 923
 924                 if (error != 0)
 925                         errno = error;
 926
 927                 va_copy(aq, ap);
 928                 vsnprintf(buf, sizeof(buf), format, aq);
 929                 va_end(aq);
 930
 931                 if (startswith(buf, "MESSAGE=")) {
 932                         found = true;
 933                         break;
 934                 }
 935
 936                 VA_FORMAT_ADVANCE(format, ap);
 937
 938                 format = va_arg(ap, char *);
 939         }
 940         va_end(ap);
 941
 942         if (!found)
 943                 return -error;
 944
 945         return log_dispatch(level, error, file, line, func, NULL, NULL, NULL, NULL, buf + 8);
 946 }
 947
 948 int log_set_target_from_string(const char *e) {
 949         LogTarget t;
 950
 951         t = log_target_from_string(e);
 952         if (t < 0)
 953                 return -EINVAL;
 954
 955         log_set_target(t);
 956         return 0;
 957 }
 958
 959 int log_set_max_level_from_string(const char *e) {
 960         int t;
 961
 962         t = log_level_from_string(e);
 963         if (t < 0)
 964                 return -EINVAL;
 965
 966         log_set_max_level(t);
 967         return 0;
 968 }
 969
 970 static int parse_proc_cmdline_item(const char *key, const char *value) {
 971
 972         /*
 973          * The systemd.log_xyz= settings are parsed by all tools, and
 974          * so is "debug".
 975          *
 976          * However, "quiet" is only parsed by PID 1, and only turns of
 977          * status output to /dev/console, but does not alter the log
 978          * level.
 979          */
 980
 981         if (streq(key, "debug") && !value)
 982                 log_set_max_level(LOG_DEBUG);
 983
 984         else if (streq(key, "systemd.log_target") && value) {
 985
 986                 if (log_set_target_from_string(value) < 0)
 987                         log_warning("Failed to parse log target '%s'. Ignoring.", value);
 988
 989         } else if (streq(key, "systemd.log_level") && value) {
 990
 991                 if (log_set_max_level_from_string(value) < 0)
 992                         log_warning("Failed to parse log level '%s'. Ignoring.", value);
 993
 994         } else if (streq(key, "systemd.log_color") && value) {
 995
 996                 if (log_show_color_from_string(value) < 0)
 997                         log_warning("Failed to parse log color setting '%s'. Ignoring.", value);
 998
 999         } else if (streq(key, "systemd.log_location") && value) {
1000
1001                 if (log_show_location_from_string(value) < 0)
1002                         log_warning("Failed to parse log location setting '%s'. Ignoring.", value);
1003         }
1004
1005         return 0;
1006 }
1007
1008 void log_parse_environment(void) {
1009         const char *e;
1010
1011         if (get_ctty_devnr(0, NULL) < 0)
1012                 /* Only try to read the command line in daemons.
1013                    We assume that anything that has a controlling
1014                    tty is user stuff. */
1015                 (void) parse_proc_cmdline(parse_proc_cmdline_item);
1016
1017         e = secure_getenv("SYSTEMD_LOG_TARGET");
1018         if (e && log_set_target_from_string(e) < 0)
1019                 log_warning("Failed to parse log target '%s'. Ignoring.", e);
1020
1021         e = secure_getenv("SYSTEMD_LOG_LEVEL");
1022         if (e && log_set_max_level_from_string(e) < 0)
1023                 log_warning("Failed to parse log level '%s'. Ignoring.", e);
1024
1025         e = secure_getenv("SYSTEMD_LOG_COLOR");
1026         if (e && log_show_color_from_string(e) < 0)
1027                 log_warning("Failed to parse bool '%s'. Ignoring.", e);
1028
1029         e = secure_getenv("SYSTEMD_LOG_LOCATION");
1030         if (e && log_show_location_from_string(e) < 0)
1031                 log_warning("Failed to parse bool '%s'. Ignoring.", e);
1032 }
1033
1034 LogTarget log_get_target(void) {
1035         return log_target;
1036 }
1037
1038 int log_get_max_level(void) {
1039         return log_max_level;
1040 }
1041
1042 void log_show_color(bool b) {
1043         show_color = b;
1044 }
1045
1046 bool log_get_show_color(void) {
1047         return show_color;
1048 }
1049
1050 void log_show_location(bool b) {
1051         show_location = b;
1052 }
1053
1054 bool log_get_show_location(void) {
1055         return show_location;
1056 }
1057
1058 int log_show_color_from_string(const char *e) {
1059         int t;
1060
1061         t = parse_boolean(e);
1062         if (t < 0)
1063                 return t;
1064
1065         log_show_color(t);
1066         return 0;
1067 }
1068
1069 int log_show_location_from_string(const char *e) {
1070         int t;
1071
1072         t = parse_boolean(e);
1073         if (t < 0)
1074                 return t;
1075
1076         log_show_location(t);
1077         return 0;
1078 }
1079
1080 bool log_on_console(void) {
1081         if (log_target == LOG_TARGET_CONSOLE ||
1082             log_target == LOG_TARGET_CONSOLE_PREFIXED)
1083                 return true;
1084
1085         return syslog_fd < 0 && kmsg_fd < 0 && journal_fd < 0;
1086 }
1087
1088 static const char *const log_target_table[_LOG_TARGET_MAX] = {
1089         [LOG_TARGET_CONSOLE] = "console",
1090         [LOG_TARGET_CONSOLE_PREFIXED] = "console-prefixed",
1091         [LOG_TARGET_KMSG] = "kmsg",
1092         [LOG_TARGET_JOURNAL] = "journal",
1093         [LOG_TARGET_JOURNAL_OR_KMSG] = "journal-or-kmsg",
1094         [LOG_TARGET_SYSLOG] = "syslog",
1095         [LOG_TARGET_SYSLOG_OR_KMSG] = "syslog-or-kmsg",
1096         [LOG_TARGET_AUTO] = "auto",
1097         [LOG_TARGET_SAFE] = "safe",
1098         [LOG_TARGET_NULL] = "null"
1099 };
1100
1101 DEFINE_STRING_TABLE_LOOKUP(log_target, LogTarget);
1102
1103 void log_received_signal(int level, const struct signalfd_siginfo *si) {
1104         if (si->ssi_pid > 0) {
1105                 _cleanup_free_ char *p = NULL;
1106
1107                 get_process_comm(si->ssi_pid, &p);
1108
1109                 log_full(level,
1110                          "Received SIG%s from PID %"PRIu32" (%s).",
1111                          signal_to_string(si->ssi_signo),
1112                          si->ssi_pid, strna(p));
1113         } else
1114                 log_full(level,
1115                          "Received SIG%s.",
1116                          signal_to_string(si->ssi_signo));
1117
1118 }
1119
1120 void log_set_upgrade_syslog_to_journal(bool b) {
1121         upgrade_syslog_to_journal = b;
1122 }
1123
1124 int log_syntax_internal(
1125                 const char *unit,
1126                 int level,
1127                 const char *config_file,
1128                 unsigned config_line,
1129                 int error,
1130                 const char *file,
1131                 int line,
1132                 const char *func,
1133                 const char *format, ...) {
1134
1135         PROTECT_ERRNO;
1136         char buffer[LINE_MAX];
1137         int r;
1138         va_list ap;
1139
1140         if (error < 0)
1141                 error = -error;
1142
1143         if (_likely_(LOG_PRI(level) > log_max_level))
1144                 return -error;
1145
1146         if (log_target == LOG_TARGET_NULL)
1147                 return -error;
1148
1149         if (error != 0)
1150                 errno = error;
1151
1152         va_start(ap, format);
1153         vsnprintf(buffer, sizeof(buffer), format, ap);
1154         va_end(ap);
1155
1156         if (unit)
1157                 r = log_struct_internal(
1158                                 level, error,
1159                                 file, line, func,
1160                                 getpid() == 1 ? "UNIT=%s" : "USER_UNIT=%s", unit,
1161                                 LOG_MESSAGE_ID(SD_MESSAGE_INVALID_CONFIGURATION),
1162                                 "CONFIG_FILE=%s", config_file,
1163                                 "CONFIG_LINE=%u", config_line,
1164                                 LOG_MESSAGE("[%s:%u] %s", config_file, config_line, buffer),
1165                                 NULL);
1166         else
1167                 r = log_struct_internal(
1168                                 level, error,
1169                                 file, line, func,
1170                                 LOG_MESSAGE_ID(SD_MESSAGE_INVALID_CONFIGURATION),
1171                                 "CONFIG_FILE=%s", config_file,
1172                                 "CONFIG_LINE=%u", config_line,
1173                                 LOG_MESSAGE("[%s:%u] %s", config_file, config_line, buffer),
1174                                 NULL);
1175
1176         return r;
1177 }