diff options
Diffstat (limited to 'src/shared/log.c')
| -rw-r--r-- | src/shared/log.c | 747 |
1 files changed, 747 insertions, 0 deletions
diff --git a/src/shared/log.c b/src/shared/log.c new file mode 100644 index 0000000000..9fffc1dbc0 --- /dev/null +++ b/src/shared/log.c @@ -0,0 +1,747 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2010 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <stdarg.h> +#include <stdio.h> +#include <errno.h> +#include <unistd.h> +#include <fcntl.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <stddef.h> + +#include "log.h" +#include "util.h" +#include "macro.h" +#include "socket-util.h" + +#define SNDBUF_SIZE (8*1024*1024) + +static LogTarget log_target = LOG_TARGET_CONSOLE; +static int log_max_level = LOG_INFO; +static int log_facility = LOG_DAEMON; + +static int console_fd = STDERR_FILENO; +static int syslog_fd = -1; +static int kmsg_fd = -1; +static int journal_fd = -1; + +static bool syslog_is_stream = false; + +static bool show_color = false; +static bool show_location = false; + +/* Akin to glibc's __abort_msg; which is private and we hence cannot + * use here. */ +static char *log_abort_msg = NULL; + +void log_close_console(void) { + + if (console_fd < 0) + return; + + if (getpid() == 1) { + if (console_fd >= 3) + close_nointr_nofail(console_fd); + + console_fd = -1; + } +} + +static int log_open_console(void) { + + if (console_fd >= 0) + return 0; + + if (getpid() == 1) { + + console_fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC); + if (console_fd < 0) { + log_error("Failed to open /dev/console for logging: %s", strerror(-console_fd)); + return console_fd; + } + + log_debug("Successfully 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; + + kmsg_fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC); + if (kmsg_fd < 0) { + log_error("Failed to open /dev/kmsg for logging: %s", strerror(errno)); + return -errno; + } + + log_debug("Successfully opened /dev/kmsg for logging."); + + return 0; +} + +void log_close_syslog(void) { + + if (syslog_fd < 0) + return; + + close_nointr_nofail(syslog_fd); + syslog_fd = -1; +} + +static int create_log_socket(int type) { + int fd; + + /* All output to the syslog/journal fds we do asynchronously, + * and if the buffers are full we just drop the messages */ + + fd = socket(AF_UNIX, type|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); + if (fd < 0) + return -errno; + + fd_inc_sndbuf(fd, SNDBUF_SIZE); + + return fd; +} + +static int log_open_syslog(void) { + union sockaddr_union sa; + int r; + + if (syslog_fd >= 0) + return 0; + + zero(sa); + sa.un.sun_family = AF_UNIX; + strncpy(sa.un.sun_path, "/dev/log", sizeof(sa.un.sun_path)); + + syslog_fd = create_log_socket(SOCK_DGRAM); + if (syslog_fd < 0) { + r = syslog_fd; + goto fail; + } + + if (connect(syslog_fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) { + close_nointr_nofail(syslog_fd); + + /* Some legacy syslog systems still use stream + * sockets. They really shouldn't. But what can we + * do... */ + syslog_fd = create_log_socket(SOCK_STREAM); + if (syslog_fd < 0) { + r = syslog_fd; + goto fail; + } + + if (connect(syslog_fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) { + r = -errno; + goto fail; + } + + syslog_is_stream = true; + } else + syslog_is_stream = false; + + log_debug("Successfully opened syslog for logging."); + + return 0; + +fail: + log_close_syslog(); + log_debug("Failed to open syslog for logging: %s", strerror(-r)); + return r; +} + +void log_close_journal(void) { + + if (journal_fd < 0) + return; + + close_nointr_nofail(journal_fd); + journal_fd = -1; +} + +static int log_open_journal(void) { + union sockaddr_union sa; + int r; + + if (journal_fd >= 0) + return 0; + + journal_fd = create_log_socket(SOCK_DGRAM); + if (journal_fd < 0) { + r = journal_fd; + goto fail; + } + + zero(sa); + sa.un.sun_family = AF_UNIX; + strncpy(sa.un.sun_path, "/run/systemd/journal/socket", sizeof(sa.un.sun_path)); + + if (connect(journal_fd, &sa.sa, offsetof(struct sockaddr_un, sun_path) + strlen(sa.un.sun_path)) < 0) { + r = -errno; + goto fail; + } + + log_debug("Successfully opened journal for logging."); + + return 0; + +fail: + log_close_journal(); + log_debug("Failed to open journal 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_NULL) { + log_close_journal(); + log_close_syslog(); + log_close_console(); + return 0; + } + + if (log_target != LOG_TARGET_AUTO || + getpid() == 1 || + isatty(STDERR_FILENO) <= 0) { + + if (log_target == LOG_TARGET_AUTO || + log_target == LOG_TARGET_JOURNAL_OR_KMSG || + log_target == LOG_TARGET_JOURNAL) { + r = log_open_journal(); + if (r >= 0) { + log_close_syslog(); + log_close_console(); + return r; + } + } + + if (log_target == LOG_TARGET_SYSLOG_OR_KMSG || + log_target == LOG_TARGET_SYSLOG) { + r = log_open_syslog(); + if (r >= 0) { + log_close_journal(); + log_close_console(); + return r; + } + } + + if (log_target == LOG_TARGET_AUTO || + log_target == LOG_TARGET_JOURNAL_OR_KMSG || + log_target == LOG_TARGET_SYSLOG_OR_KMSG || + log_target == LOG_TARGET_KMSG) { + r = log_open_kmsg(); + if (r >= 0) { + log_close_journal(); + log_close_syslog(); + log_close_console(); + return r; + } + } + } + + log_close_journal(); + log_close_syslog(); + + /* Get the real /dev/console if we are PID=1, hence reopen */ + log_close_console(); + return log_open_console(); +} + +void log_set_target(LogTarget target) { + assert(target >= 0); + assert(target < _LOG_TARGET_MAX); + + log_target = target; +} + +void log_close(void) { + log_close_journal(); + log_close_syslog(); + log_close_kmsg(); + log_close_console(); +} + +void log_forget_fds(void) { + console_fd = kmsg_fd = syslog_fd = journal_fd = -1; +} + +void log_set_max_level(int level) { + assert((level & LOG_PRIMASK) == level); + + log_max_level = level; +} + +void log_set_facility(int facility) { + log_facility = facility; +} + +static int write_to_console( + int level, + const char*file, + int line, + const char *func, + const char *buffer) { + + char location[64]; + struct iovec iovec[5]; + unsigned n = 0; + bool highlight; + + if (console_fd < 0) + return 0; + + highlight = LOG_PRI(level) <= LOG_ERR && show_color; + + zero(iovec); + + if (show_location) { + snprintf(location, sizeof(location), "(%s:%u) ", file, line); + char_array_0(location); + IOVEC_SET_STRING(iovec[n++], location); + } + + if (highlight) + IOVEC_SET_STRING(iovec[n++], ANSI_HIGHLIGHT_RED_ON); + IOVEC_SET_STRING(iovec[n++], buffer); + if (highlight) + IOVEC_SET_STRING(iovec[n++], ANSI_HIGHLIGHT_OFF); + IOVEC_SET_STRING(iovec[n++], "\n"); + + if (writev(console_fd, iovec, n) < 0) + return -errno; + + return 1; +} + +static int write_to_syslog( + int level, + const char*file, + int line, + const char *func, + const char *buffer) { + + char header_priority[16], header_time[64], header_pid[16]; + struct iovec iovec[5]; + struct msghdr msghdr; + time_t t; + struct tm *tm; + + if (syslog_fd < 0) + return 0; + + snprintf(header_priority, sizeof(header_priority), "<%i>", level); + char_array_0(header_priority); + + t = (time_t) (now(CLOCK_REALTIME) / USEC_PER_SEC); + if (!(tm = localtime(&t))) + return -EINVAL; + + if (strftime(header_time, sizeof(header_time), "%h %e %T ", tm) <= 0) + return -EINVAL; + + snprintf(header_pid, sizeof(header_pid), "[%lu]: ", (unsigned long) getpid()); + char_array_0(header_pid); + + zero(iovec); + IOVEC_SET_STRING(iovec[0], header_priority); + IOVEC_SET_STRING(iovec[1], header_time); + IOVEC_SET_STRING(iovec[2], program_invocation_short_name); + IOVEC_SET_STRING(iovec[3], header_pid); + IOVEC_SET_STRING(iovec[4], buffer); + + /* When using syslog via SOCK_STREAM separate the messages by NUL chars */ + if (syslog_is_stream) + iovec[4].iov_len++; + + zero(msghdr); + msghdr.msg_iov = iovec; + msghdr.msg_iovlen = ELEMENTSOF(iovec); + + for (;;) { + ssize_t n; + + n = sendmsg(syslog_fd, &msghdr, MSG_NOSIGNAL); + if (n < 0) + return -errno; + + if (!syslog_is_stream || + (size_t) n >= IOVEC_TOTAL_SIZE(iovec, ELEMENTSOF(iovec))) + break; + + IOVEC_INCREMENT(iovec, ELEMENTSOF(iovec), n); + } + + return 1; +} + +static int write_to_kmsg( + int level, + const char*file, + int line, + const char *func, + const char *buffer) { + + char header_priority[16], header_pid[16]; + struct iovec iovec[5]; + + if (kmsg_fd < 0) + return 0; + + snprintf(header_priority, sizeof(header_priority), "<%i>", level); + char_array_0(header_priority); + + snprintf(header_pid, sizeof(header_pid), "[%lu]: ", (unsigned long) getpid()); + char_array_0(header_pid); + + zero(iovec); + IOVEC_SET_STRING(iovec[0], header_priority); + IOVEC_SET_STRING(iovec[1], program_invocation_short_name); + IOVEC_SET_STRING(iovec[2], header_pid); + IOVEC_SET_STRING(iovec[3], buffer); + IOVEC_SET_STRING(iovec[4], "\n"); + + if (writev(kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0) + return -errno; + + return 1; +} + +static int write_to_journal( + int level, + const char*file, + int line, + const char *func, + const char *buffer) { + + char header[LINE_MAX]; + struct iovec iovec[3]; + struct msghdr mh; + + if (journal_fd < 0) + return 0; + + snprintf(header, sizeof(header), + "PRIORITY=%i\n" + "SYSLOG_FACILITY=%i\n" + "CODE_FILE=%s\n" + "CODE_LINE=%i\n" + "CODE_FUNCTION=%s\n" + "MESSAGE=", + LOG_PRI(level), + LOG_FAC(level), + file, + line, + func); + + char_array_0(header); + + zero(iovec); + IOVEC_SET_STRING(iovec[0], header); + IOVEC_SET_STRING(iovec[1], buffer); + IOVEC_SET_STRING(iovec[2], "\n"); + + zero(mh); + mh.msg_iov = iovec; + mh.msg_iovlen = ELEMENTSOF(iovec); + + if (sendmsg(journal_fd, &mh, MSG_NOSIGNAL) < 0) + return -errno; + + return 1; +} + +static int log_dispatch( + int level, + const char*file, + int line, + const char *func, + char *buffer) { + + int r = 0; + + if (log_target == LOG_TARGET_NULL) + return 0; + + /* Patch in LOG_DAEMON facility if necessary */ + if ((level & LOG_FACMASK) == 0) + level = log_facility | LOG_PRI(level); + + do { + char *e; + int k = 0; + + buffer += strspn(buffer, NEWLINE); + + if (buffer[0] == 0) + break; + + if ((e = strpbrk(buffer, NEWLINE))) + *(e++) = 0; + + if (log_target == LOG_TARGET_AUTO || + log_target == LOG_TARGET_JOURNAL_OR_KMSG || + log_target == LOG_TARGET_JOURNAL) { + + k = write_to_journal(level, file, line, func, buffer); + if (k < 0) { + if (k != -EAGAIN) + log_close_journal(); + log_open_kmsg(); + } else if (k > 0) + r++; + } + + if (log_target == LOG_TARGET_SYSLOG_OR_KMSG || + log_target == LOG_TARGET_SYSLOG) { + + k = write_to_syslog(level, file, line, func, buffer); + if (k < 0) { + if (k != -EAGAIN) + log_close_syslog(); + log_open_kmsg(); + } else if (k > 0) + r++; + } + + if (k <= 0 && + (log_target == LOG_TARGET_AUTO || + log_target == LOG_TARGET_SYSLOG_OR_KMSG || + log_target == LOG_TARGET_KMSG)) { + + k = write_to_kmsg(level, file, line, func, buffer); + if (k < 0) { + log_close_kmsg(); + log_open_console(); + } else if (k > 0) + r++; + } + + if (k <= 0) { + k = write_to_console(level, file, line, func, buffer); + if (k < 0) + return k; + } + + buffer = e; + } while (buffer); + + return r; +} + +int log_dump_internal( + int level, + const char*file, + int line, + const char *func, + char *buffer) { + + int saved_errno, r; + + /* This modifies the buffer... */ + + if (_likely_(LOG_PRI(level) > log_max_level)) + return 0; + + saved_errno = errno; + r = log_dispatch(level, file, line, func, buffer); + errno = saved_errno; + + return r; +} + +int log_metav( + int level, + const char*file, + int line, + const char *func, + const char *format, + va_list ap) { + + char buffer[LINE_MAX]; + int saved_errno, r; + + if (_likely_(LOG_PRI(level) > log_max_level)) + return 0; + + saved_errno = errno; + vsnprintf(buffer, sizeof(buffer), format, ap); + char_array_0(buffer); + + r = log_dispatch(level, file, line, func, buffer); + errno = saved_errno; + + return r; +} + +int log_meta( + int level, + const char*file, + int line, + const char *func, + const char *format, ...) { + + int r; + va_list ap; + + va_start(ap, format); + r = log_metav(level, file, line, func, format, ap); + va_end(ap); + + return r; +} + +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wformat-nonliteral" +_noreturn_ static void log_assert(const char *text, const char *file, int line, const char *func, const char *format) { + static char buffer[LINE_MAX]; + + snprintf(buffer, sizeof(buffer), format, text, file, line, func); + + char_array_0(buffer); + log_abort_msg = buffer; + + log_dispatch(LOG_CRIT, file, line, func, buffer); + abort(); +} +#pragma GCC diagnostic pop + +_noreturn_ void log_assert_failed(const char *text, const char *file, int line, const char *func) { + log_assert(text, file, line, func, "Assertion '%s' failed at %s:%u, function %s(). Aborting."); +} + +_noreturn_ void log_assert_failed_unreachable(const char *text, const char *file, int line, const char *func) { + log_assert(text, file, line, func, "Code should not be reached '%s' at %s:%u, function %s(). Aborting."); +} + +int log_set_target_from_string(const char *e) { + LogTarget t; + + t = log_target_from_string(e); + if (t < 0) + return -EINVAL; + + log_set_target(t); + return 0; +} + +int log_set_max_level_from_string(const char *e) { + int t; + + t = log_level_from_string(e); + if (t < 0) + return t; + + 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); + + if ((e = getenv("SYSTEMD_LOG_COLOR"))) + if (log_show_color_from_string(e) < 0) + log_warning("Failed to parse bool %s. Ignoring.", e); + + if ((e = getenv("SYSTEMD_LOG_LOCATION"))) + if (log_show_location_from_string(e) < 0) + log_warning("Failed to parse bool %s. Ignoring.", e); +} + +LogTarget log_get_target(void) { + return log_target; +} + +int log_get_max_level(void) { + return log_max_level; +} + +void log_show_color(bool b) { + show_color = b; +} + +void log_show_location(bool b) { + show_location = b; +} + +int log_show_color_from_string(const char *e) { + int t; + + t = parse_boolean(e); + if (t < 0) + return t; + + log_show_color(t); + return 0; +} + +int log_show_location_from_string(const char *e) { + int t; + + t = parse_boolean(e); + if (t < 0) + return t; + + log_show_location(t); + return 0; +} + +static const char *const log_target_table[] = { + [LOG_TARGET_CONSOLE] = "console", + [LOG_TARGET_KMSG] = "kmsg", + [LOG_TARGET_JOURNAL] = "journal", + [LOG_TARGET_JOURNAL_OR_KMSG] = "journal-or-kmsg", + [LOG_TARGET_SYSLOG] = "syslog", + [LOG_TARGET_SYSLOG_OR_KMSG] = "syslog-or-kmsg", + [LOG_TARGET_AUTO] = "auto", + [LOG_TARGET_NULL] = "null" +}; + +DEFINE_STRING_TABLE_LOOKUP(log_target, LogTarget); |