/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include #include #include #include #include #include "sd-id128.h" #include "sd-journal.h" #include "alloc-util.h" #include "build.h" #include "fd-util.h" #include "fileio.h" #include "io-util.h" #include "log.h" #include "logs-show.h" #include "main-func.h" #include "pretty-print.h" #include "qrcode-util.h" #include "sigbus.h" #include "signal-util.h" #include "sysctl-util.h" #include "terminal-util.h" static bool arg_continuous = false; static int help(void) { _cleanup_free_ char *link = NULL; int r; r = terminal_urlify_man("systemd-bsod", "8", &link); if (r < 0) return log_oom(); printf("%s\n\n" "%sFilter the journal to fetch the first message from the\n" "current boot with an emergency log level and displays it\n" "as a string and a QR code.\n\n%s" " -h --help Show this help\n" " --version Show package version\n" " -c --continuous Make systemd-bsod wait continuously\n" " for changes in the journal\n" "\nSee the %s for details.\n", program_invocation_short_name, ansi_highlight(), ansi_normal(), link); return 0; } static int acquire_first_emergency_log_message(char **ret) { _cleanup_(sd_journal_closep) sd_journal *j = NULL; _cleanup_free_ char *message = NULL; const void *d; size_t l; int r; assert(ret); r = sd_journal_open(&j, SD_JOURNAL_LOCAL_ONLY); if (r < 0) return log_error_errno(r, "Failed to open journal: %m"); r = add_match_this_boot(j, NULL); if (r < 0) return log_warning_errno(r, "Failed to add boot ID filter: %m"); r = sd_journal_add_match(j, "_UID=0", 0); if (r < 0) return log_warning_errno(r, "Failed to add User ID filter: %m"); assert_cc(0 == LOG_EMERG); r = sd_journal_add_match(j, "PRIORITY=0", 0); if (r < 0) return log_warning_errno(r, "Failed to add Emergency filter: %m"); r = sd_journal_seek_head(j); if (r < 0) return log_error_errno(r, "Failed to seek to start of journal: %m"); for (;;) { r = sd_journal_next(j); if (r < 0) return log_error_errno(r, "Failed to read next journal entry: %m"); if (r > 0) break; if (!arg_continuous) { log_debug("No emergency level entries in the journal"); *ret = NULL; return 0; } r = sd_journal_wait(j, UINT64_MAX); if (r < 0) return log_error_errno(r, "Failed to wait for changes: %m"); } r = sd_journal_get_data(j, "MESSAGE", &d, &l); if (r < 0) return log_error_errno(r, "Failed to read journal message: %m"); message = memdup_suffix0((const char*)d + STRLEN("MESSAGE="), l - STRLEN("MESSAGE=")); if (!message) return log_oom(); *ret = TAKE_PTR(message); return 0; } static int find_next_free_vt(int fd, int *ret_free_vt, int *ret_original_vt) { struct vt_stat terminal_status; assert(fd >= 0); assert(ret_free_vt); assert(ret_original_vt); if (ioctl(fd, VT_GETSTATE, &terminal_status) < 0) return -errno; for (size_t i = 0; i < sizeof(terminal_status.v_state) * 8; i++) if ((terminal_status.v_state & (1 << i)) == 0) { *ret_free_vt = i; *ret_original_vt = terminal_status.v_active; return 0; } return log_error_errno(SYNTHETIC_ERRNO(ENOTTY), "No free VT found: %m"); } static int display_emergency_message_fullscreen(const char *message) { int r, ret = 0, free_vt = 0, original_vt = 0; unsigned qr_code_start_row = 1, qr_code_start_column = 1; char tty[STRLEN("/dev/tty") + DECIMAL_STR_MAX(int) + 1]; _cleanup_close_ int fd = -EBADF; _cleanup_fclose_ FILE *f = NULL; char read_character_buffer = '\0'; struct winsize w = { .ws_col = 80, .ws_row = 25, }; assert(message); fd = open_terminal("/dev/tty1", O_RDWR|O_NOCTTY|O_CLOEXEC); if (fd < 0) return log_error_errno(fd, "Failed to open tty1: %m"); r = find_next_free_vt(fd, &free_vt, &original_vt); if (r < 0) return log_error_errno(r, "Failed to find a free VT: %m"); xsprintf(tty, "/dev/tty%d", free_vt + 1); r = open_terminal(tty, O_RDWR|O_NOCTTY|O_CLOEXEC); if (r < 0) return log_error_errno(fd, "Failed to open tty: %m"); close_and_replace(fd, r); if (ioctl(fd, TIOCGWINSZ, &w) < 0) log_warning_errno(errno, "Failed to fetch tty size, ignoring: %m"); if (ioctl(fd, VT_ACTIVATE, free_vt + 1) < 0) return log_error_errno(errno, "Failed to activate tty: %m"); r = loop_write(fd, ANSI_BACKGROUND_BLUE ANSI_HOME_CLEAR, SIZE_MAX); if (r < 0) log_warning_errno(r, "Failed to clear terminal, ignoring: %m"); r = set_terminal_cursor_position(fd, 2, 4); if (r < 0) log_warning_errno(r, "Failed to move terminal cursor position, ignoring: %m"); r = loop_write(fd, "The current boot has failed!", SIZE_MAX); if (r < 0) { ret = log_warning_errno(r, "Failed to write to terminal: %m"); goto cleanup; } qr_code_start_row = w.ws_row * 3U / 5U; qr_code_start_column = w.ws_col * 3U / 4U; r = set_terminal_cursor_position(fd, 4, 4); if (r < 0) log_warning_errno(r, "Failed to move terminal cursor position, ignoring: %m"); r = loop_write(fd, message, SIZE_MAX); if (r < 0) { ret = log_warning_errno(r, "Failed to write emergency message to terminal: %m"); goto cleanup; } r = fdopen_independent(fd, "r+", &f); if (r < 0) { ret = log_error_errno(errno, "Failed to open output file: %m"); goto cleanup; } r = print_qrcode_full(f, "Scan the error message", message, qr_code_start_row, qr_code_start_column, w.ws_col, w.ws_row, /* check_tty= */ false); if (r < 0) log_warning_errno(r, "QR code could not be printed, ignoring: %m"); r = set_terminal_cursor_position(fd, w.ws_row - 1, w.ws_col * 2U / 5U); if (r < 0) log_warning_errno(r, "Failed to move terminal cursor position, ignoring: %m"); r = loop_write(fd, "Press any key to exit...", SIZE_MAX); if (r < 0) { ret = log_warning_errno(r, "Failed to write to terminal: %m"); goto cleanup; } r = read_one_char(f, &read_character_buffer, USEC_INFINITY, NULL); if (r < 0 && r != -EINTR) ret = log_error_errno(r, "Failed to read character: %m"); cleanup: if (ioctl(fd, VT_ACTIVATE, original_vt) < 0) return log_error_errno(errno, "Failed to switch back to original VT: %m"); return ret; } static int parse_argv(int argc, char * argv[]) { enum { ARG_VERSION = 0x100, }; static const struct option options[] = { { "help", no_argument, NULL, 'h' }, { "version", no_argument, NULL, ARG_VERSION }, { "continuous", no_argument, NULL, 'c' }, {} }; int c; assert(argc >= 0); assert(argv); while ((c = getopt_long(argc, argv, "hc", options, NULL)) >= 0) switch (c) { case 'h': return help(); case ARG_VERSION: return version(); case 'c': arg_continuous = true; break; case '?': return -EINVAL; default: assert_not_reached(); } if (optind < argc) return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "%s takes no argument.", program_invocation_short_name); return 1; } static int run(int argc, char *argv[]) { /* Don't use SA_RESTART here, as we don't want to restart syscalls on signal * to get out of read_one_char() when needed */ static const struct sigaction nop_sigaction = { .sa_handler = nop_signal_handler, .sa_flags = 0, }; _cleanup_free_ char *message = NULL; int r; log_open(); log_parse_environment(); sigbus_install(); r = parse_argv(argc, argv); if (r <= 0) return r; r = acquire_first_emergency_log_message(&message); if (r < 0) return log_error_errno(r, "Failed to acquire first emergency log message: %m"); if (!message) { log_debug("No emergency-level entries"); return 0; } assert_se(sigaction_many(&nop_sigaction, SIGTERM, SIGINT) >= 0); r = display_emergency_message_fullscreen((const char*) message); if (r < 0) return log_error_errno(r, "Failed to display emergency message on terminal: %m"); return 0; } DEFINE_MAIN_FUNCTION(run);