X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=log.c;h=5d17955e7ebbd9ddb25a933b8faebac4192bb9fe;hp=879cb537336e8461fec1c02ea79bceb79b41eeab;hb=43aa226daf2abe7af37d86379b4bf69efbc03f78;hpb=2d368c149b90a7b284035f8883eb0c3e64a2caab diff --git a/log.c b/log.c index 879cb5373..5d17955e7 100644 --- a/log.c +++ b/log.c @@ -37,42 +37,78 @@ static LogTarget log_target = LOG_TARGET_CONSOLE; static int log_max_level = LOG_DEBUG; +static int console_fd = STDERR_FILENO; static int syslog_fd = -1; static int kmsg_fd = -1; -void log_close_kmsg(void) { +/* Akin to glibc's __abort_msg; which is private and we hance cannot + * use here. */ +static char *log_abort_msg = NULL; + +void log_close_console(void) { + + if (console_fd < 0) + return; - if (kmsg_fd >= 0) { - close_nointr(kmsg_fd); - kmsg_fd = -1; + if (getpid() == 1 || console_fd != STDERR_FILENO) { + close_nointr_nofail(console_fd); + console_fd = -1; } } -int log_open_kmsg(void) { +static int log_open_console(void) { - if (log_target != LOG_TARGET_KMSG) { - log_close_kmsg(); + if (console_fd >= 0) return 0; - } + + if (getpid() == 1) { + + if ((console_fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0) { + log_error("Failed to open /dev/console for logging: %s", strerror(-console_fd)); + return console_fd; + } + + log_info("Succesfully opened /dev/console for logging."); + } else + console_fd = STDERR_FILENO; + + return 0; +} + +void log_close_kmsg(void) { + + if (kmsg_fd < 0) + return; + + close_nointr_nofail(kmsg_fd); + kmsg_fd = -1; +} + +static int log_open_kmsg(void) { if (kmsg_fd >= 0) return 0; - if ((kmsg_fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0) + if ((kmsg_fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0) { + log_info("Failed to open /dev/kmsg for logging: %s", strerror(errno)); return -errno; + } + + log_info("Succesfully opened /dev/kmsg for logging."); return 0; } void log_close_syslog(void) { - if (syslog_fd >= 0) { - close_nointr(syslog_fd); - syslog_fd = -1; - } + if (syslog_fd < 0) + return; + + close_nointr_nofail(syslog_fd); + syslog_fd = -1; } -int log_open_syslog(void) { +static int log_open_syslog(void) { union { struct sockaddr sa; struct sockaddr_un un; @@ -80,24 +116,20 @@ int log_open_syslog(void) { struct timeval tv; int r; - if (log_target != LOG_TARGET_SYSLOG) { - log_close_syslog(); - return 0; - } - if (syslog_fd >= 0) return 0; - if ((syslog_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) - return -errno; + if ((syslog_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) { + r = -errno; + goto fail; + } /* Make sure we don't block for more than 5s when talking to * syslog */ timeval_store(&tv, SYSLOG_TIMEOUT_USEC); if (setsockopt(syslog_fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv)) < 0) { r = -errno; - log_close_syslog(); - return r; + goto fail; } zero(sa); @@ -106,11 +138,45 @@ int log_open_syslog(void) { if (connect(syslog_fd, &sa.sa, sizeof(sa)) < 0) { r = -errno; - log_close_syslog(); - return -errno; + goto fail; } + log_info("Succesfully opened syslog for logging."); + return 0; + +fail: + log_close_syslog(); + log_info("Failed to open syslog for logging: %s", strerror(-r)); + return r; +} + +int log_open(void) { + int r; + + /* If we don't use the console we close it here, to not get + * killed by SAK. If we don't use syslog we close it here so + * that we are not confused by somebody deleting the socket in + * the fs. If we don't use /dev/kmsg we still keep it open, + * because there is no reason to close it. */ + + if (log_target == LOG_TARGET_SYSLOG_OR_KMSG || + log_target == LOG_TARGET_SYSLOG) + if ((r = log_open_syslog()) >= 0) { + log_close_console(); + return r; + } + + if (log_target == LOG_TARGET_SYSLOG_OR_KMSG || + log_target == LOG_TARGET_KMSG) + if ((r = log_open_kmsg()) >= 0) { + log_close_syslog(); + log_close_console(); + return r; + } + + log_close_syslog(); + return log_open_console(); } void log_set_target(LogTarget target) { @@ -126,27 +192,39 @@ void log_set_max_level(int level) { log_max_level = level; } -static void write_to_console( +static int write_to_console( int level, const char*file, int line, const char *func, - const char *format, - va_list ap) { + const char *buffer) { - const char *prefix, *suffix; + char location[64]; + struct iovec iovec[5]; + unsigned n = 0; + bool highlight; - if (LOG_PRI(level) <= LOG_ERR) { - prefix = "\x1B[1;31m"; - suffix = "\x1B[0m"; - } else { - prefix = ""; - suffix = ""; - } + if (console_fd < 0) + return 0; + + snprintf(location, sizeof(location), "(%s:%u) ", file, line); + char_array_0(location); + + highlight = LOG_PRI(level) <= LOG_ERR; + + zero(iovec); + IOVEC_SET_STRING(iovec[n++], location); + if (highlight) + IOVEC_SET_STRING(iovec[n++], "\x1B[1;31m"); + IOVEC_SET_STRING(iovec[n++], buffer); + if (highlight) + IOVEC_SET_STRING(iovec[n++], "\x1B[0m"); + IOVEC_SET_STRING(iovec[n++], "\n"); + + if (writev(console_fd, iovec, n) < 0) + return -errno; - fprintf(stderr, "(%s:%u) %s", file, line, prefix); - vfprintf(stderr, format, ap); - fprintf(stderr, "%s\n", suffix); + return 1; } static int write_to_syslog( @@ -154,18 +232,16 @@ static int write_to_syslog( const char*file, int line, const char *func, - const char *format, - va_list ap) { + const char *buffer) { char header_priority[16], header_time[64], header_pid[16]; - char buffer[LOG_BUFFER_MAX]; struct iovec iovec[5]; struct msghdr msghdr; time_t t; struct tm *tm; if (syslog_fd < 0) - return -EIO; + return 0; snprintf(header_priority, sizeof(header_priority), "<%i>", LOG_MAKEPRI(LOG_DAEMON, LOG_PRI(level))); char_array_0(header_priority); @@ -180,9 +256,6 @@ static int write_to_syslog( snprintf(header_pid, sizeof(header_pid), "[%llu]: ", (unsigned long long) getpid()); char_array_0(header_pid); - vsnprintf(buffer, sizeof(buffer), format, ap); - char_array_0(buffer); - zero(iovec); IOVEC_SET_STRING(iovec[0], header_priority); IOVEC_SET_STRING(iovec[1], header_time); @@ -197,7 +270,7 @@ static int write_to_syslog( if (sendmsg(syslog_fd, &msghdr, 0) < 0) return -errno; - return 0; + return 1; } static int write_to_kmsg( @@ -205,15 +278,13 @@ static int write_to_kmsg( const char*file, int line, const char *func, - const char *format, - va_list ap) { + const char *buffer) { char header_priority[16], header_pid[16]; - char buffer[LOG_BUFFER_MAX]; struct iovec iovec[5]; if (kmsg_fd < 0) - return -EIO; + return 0; snprintf(header_priority, sizeof(header_priority), "<%i>", LOG_PRI(level)); char_array_0(header_priority); @@ -221,54 +292,148 @@ static int write_to_kmsg( snprintf(header_pid, sizeof(header_pid), "[%llu]: ", (unsigned long long) getpid()); char_array_0(header_pid); - vsnprintf(buffer, sizeof(buffer), format, ap); - char_array_0(buffer); - zero(iovec); IOVEC_SET_STRING(iovec[0], header_priority); IOVEC_SET_STRING(iovec[1], __progname); IOVEC_SET_STRING(iovec[2], header_pid); IOVEC_SET_STRING(iovec[3], buffer); - IOVEC_SET_STRING(iovec[4], (char*) "\n"); + IOVEC_SET_STRING(iovec[4], "\n"); if (writev(kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0) return -errno; - return 0; + return 1; } -void log_meta( +static int log_dispatch( + int level, + const char*file, + int line, + const char *func, + const char *buffer) { + + int r; + + if (log_target == LOG_TARGET_SYSLOG_OR_KMSG || + log_target == LOG_TARGET_SYSLOG) { + + if ((r = write_to_syslog(level, file, line, func, buffer)) < 0) { + log_close_syslog(); + log_open_kmsg(); + } else if (r > 0) + return r; + } + + if (log_target == LOG_TARGET_SYSLOG_OR_KMSG || + log_target == LOG_TARGET_KMSG) { + + if ((r = write_to_kmsg(level, file, line, func, buffer)) < 0) { + log_close_kmsg(); + log_open_console(); + } else if (r > 0) + return r; + } + + return write_to_console(level, file, line, func, buffer); +} + +int log_meta( int level, const char*file, int line, const char *func, const char *format, ...) { + char buffer[LOG_BUFFER_MAX]; + int saved_errno, r; va_list ap; - bool written; - int saved_errno; - if (LOG_PRI(level) > log_max_level) - return; + if (_likely(LOG_PRI(level) > log_max_level)) + return 0; saved_errno = errno; - written = false; - - if (log_target == LOG_TARGET_KMSG) { - va_start(ap, format); - written = write_to_kmsg(level, file, line, func, format, ap) >= 0; - va_end(ap); - } else if (log_target == LOG_TARGET_SYSLOG) { - va_start(ap, format); - written = write_to_syslog(level, file, line, func, format, ap) >= 0; - va_end(ap); - } - if (!written) { - va_start(ap, format); - write_to_console(level, file, line, func, format, ap); - va_end(ap); - } + va_start(ap, format); + vsnprintf(buffer, sizeof(buffer), format, ap); + va_end(ap); + char_array_0(buffer); + + r = log_dispatch(level, file, line, func, buffer); errno = saved_errno; + + return r; } + +void log_assert( + const char*file, + int line, + const char *func, + const char *format, ...) { + + static char buffer[LOG_BUFFER_MAX]; + int saved_errno = errno; + va_list ap; + + va_start(ap, format); + vsnprintf(buffer, sizeof(buffer), format, ap); + va_end(ap); + + char_array_0(buffer); + log_abort_msg = buffer; + + log_dispatch(LOG_CRIT, file, line, func, buffer); + abort(); + + /* If the user chose to ignore this SIGABRT, we are happy to go on, as if nothing happened. */ + errno = saved_errno; +} + +int log_set_target_from_string(const char *e) { + LogTarget t; + + if ((t = log_target_from_string(e)) < 0) + return -EINVAL; + + log_set_target(t); + return 0; +} + +int log_set_max_level_from_string(const char *e) { + int t; + + if ((t = log_level_from_string(e)) < 0) + return -EINVAL; + + log_set_max_level(t); + return 0; +} + +void log_parse_environment(void) { + const char *e; + + if ((e = getenv("SYSTEMD_LOG_TARGET"))) + if (log_set_target_from_string(e) < 0) + log_warning("Failed to parse log target %s. Ignoring.", e); + + if ((e = getenv("SYSTEMD_LOG_LEVEL"))) + if (log_set_max_level_from_string(e) < 0) + log_warning("Failed to parse log level %s. Ignoring.", e); +} + +LogTarget log_get_target(void) { + return log_target; +} + +int log_get_max_level(void) { + return log_max_level; +} + +static const char *const log_target_table[] = { + [LOG_TARGET_CONSOLE] = "console", + [LOG_TARGET_SYSLOG] = "syslog", + [LOG_TARGET_KMSG] = "kmsg", + [LOG_TARGET_SYSLOG_OR_KMSG] = "syslog-or-kmsg", +}; + +DEFINE_STRING_TABLE_LOOKUP(log_target, LogTarget);