Adding upstream version 247.3.upstream/247.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1491 insertions, 0 deletions

diff --git a/src/basic/log.c b/src/basic/log.c
new file mode 100644
index 0000000..d4054cf
--- /dev/null
+++ b/src/basic/log.c
@@ -0,0 +1,1491 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <sys/signalfd.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/uio.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+#include "sd-messages.h"
+
+#include "alloc-util.h"
+#include "errno-util.h"
+#include "fd-util.h"
+#include "format-util.h"
+#include "io-util.h"
+#include "log.h"
+#include "macro.h"
+#include "missing_syscall.h"
+#include "parse-util.h"
+#include "proc-cmdline.h"
+#include "process-util.h"
+#include "ratelimit.h"
+#include "signal-util.h"
+#include "socket-util.h"
+#include "stdio-util.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "syslog-util.h"
+#include "terminal-util.h"
+#include "time-util.h"
+#include "utf8.h"
+
+#define SNDBUF_SIZE (8*1024*1024)
+
+static LogTarget log_target = LOG_TARGET_CONSOLE;
+static int log_max_level[] = {LOG_INFO, LOG_INFO};
+assert_cc(ELEMENTSOF(log_max_level) == _LOG_REALM_MAX);
+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;
+static bool show_time = false;
+static bool show_tid = false;
+
+static bool upgrade_syslog_to_journal = false;
+static bool always_reopen_console = false;
+static bool open_when_needed = false;
+static bool prohibit_ipc = false;
+
+/* Akin to glibc's __abort_msg; which is private and we hence cannot
+ * use here. */
+static char *log_abort_msg = NULL;
+
+/* An assert to use in logging functions that does not call recursively
+ * into our logging functions (since that might lead to a loop). */
+#define assert_raw(expr)                                                \
+        do {                                                            \
+                if (_unlikely_(!(expr))) {                              \
+                        fputs(#expr "\n", stderr);                      \
+                        abort();                                        \
+                }                                                       \
+        } while (false)
+
+static void log_close_console(void) {
+        console_fd = safe_close_above_stdio(console_fd);
+}
+
+static int log_open_console(void) {
+
+        if (!always_reopen_console) {
+                console_fd = STDERR_FILENO;
+                return 0;
+        }
+
+        if (console_fd < 3) {
+                int fd;
+
+                fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC);
+                if (fd < 0)
+                        return fd;
+
+                console_fd = fd_move_above_stdio(fd);
+        }
+
+        return 0;
+}
+
+static void log_close_kmsg(void) {
+        kmsg_fd = safe_close(kmsg_fd);
+}
+
+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)
+                return -errno;
+
+        kmsg_fd = fd_move_above_stdio(kmsg_fd);
+        return 0;
+}
+
+static void log_close_syslog(void) {
+        syslog_fd = safe_close(syslog_fd);
+}
+
+static int create_log_socket(int type) {
+        struct timeval tv;
+        int fd;
+
+        fd = socket(AF_UNIX, type|SOCK_CLOEXEC, 0);
+        if (fd < 0)
+                return -errno;
+
+        fd = fd_move_above_stdio(fd);
+        (void) fd_inc_sndbuf(fd, SNDBUF_SIZE);
+
+        /* We need a blocking fd here since we'd otherwise lose messages way too early. However, let's not hang forever
+         * in the unlikely case of a deadlock. */
+        if (getpid_cached() == 1)
+                timeval_store(&tv, 10 * USEC_PER_MSEC);
+        else
+                timeval_store(&tv, 10 * USEC_PER_SEC);
+        (void) setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv));
+
+        return fd;
+}
+
+static int log_open_syslog(void) {
+
+        static const union sockaddr_union sa = {
+                .un.sun_family = AF_UNIX,
+                .un.sun_path = "/dev/log",
+        };
+
+        int r;
+
+        if (syslog_fd >= 0)
+                return 0;
+
+        syslog_fd = create_log_socket(SOCK_DGRAM);
+        if (syslog_fd < 0) {
+                r = syslog_fd;
+                goto fail;
+        }
+
+        if (connect(syslog_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) {
+                safe_close(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, SOCKADDR_UN_LEN(sa.un)) < 0) {
+                        r = -errno;
+                        goto fail;
+                }
+
+                syslog_is_stream = true;
+        } else
+                syslog_is_stream = false;
+
+        return 0;
+
+fail:
+        log_close_syslog();
+        return r;
+}
+
+static void log_close_journal(void) {
+        journal_fd = safe_close(journal_fd);
+}
+
+static int log_open_journal(void) {
+
+        static const union sockaddr_union sa = {
+                .un.sun_family = AF_UNIX,
+                .un.sun_path = "/run/systemd/journal/socket",
+        };
+
+        int r;
+
+        if (journal_fd >= 0)
+                return 0;
+
+        journal_fd = create_log_socket(SOCK_DGRAM);
+        if (journal_fd < 0) {
+                r = journal_fd;
+                goto fail;
+        }
+
+        if (connect(journal_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) {
+                r = -errno;
+                goto fail;
+        }
+
+        return 0;
+
+fail:
+        log_close_journal();
+        return r;
+}
+
+static bool stderr_is_journal(void) {
+        _cleanup_free_ char *w = NULL;
+        const char *e;
+        uint64_t dev, ino;
+        struct stat st;
+
+        e = getenv("JOURNAL_STREAM");
+        if (!e)
+                return false;
+
+        if (extract_first_word(&e, &w, ":", EXTRACT_DONT_COALESCE_SEPARATORS) <= 0)
+                return false;
+        if (!e)
+                return false;
+
+        if (safe_atou64(w, &dev) < 0)
+                return false;
+        if (safe_atou64(e, &ino) < 0)
+                return false;
+
+        if (fstat(STDERR_FILENO, &st) < 0)
+                return false;
+
+        return st.st_dev == dev && st.st_ino == ino;
+}
+
+int log_open(void) {
+        int r;
+
+        /* Do not call from library code. */
+
+        /* 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, and to make sure we don't use it if prohibit_ipc is
+         * set. 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 (getpid_cached() == 1 ||
+            stderr_is_journal() ||
+            IN_SET(log_target,
+                   LOG_TARGET_KMSG,
+                   LOG_TARGET_JOURNAL,
+                   LOG_TARGET_JOURNAL_OR_KMSG,
+                   LOG_TARGET_SYSLOG,
+                   LOG_TARGET_SYSLOG_OR_KMSG)) {
+
+                if (!prohibit_ipc) {
+                        if (IN_SET(log_target,
+                                   LOG_TARGET_AUTO,
+                                   LOG_TARGET_JOURNAL_OR_KMSG,
+                                   LOG_TARGET_JOURNAL)) {
+
+                                r = log_open_journal();
+                                if (r >= 0) {
+                                        log_close_syslog();
+                                        log_close_console();
+                                        return r;
+                                }
+                        }
+
+                        if (IN_SET(log_target,
+                                   LOG_TARGET_SYSLOG_OR_KMSG,
+                                   LOG_TARGET_SYSLOG)) {
+
+                                r = log_open_syslog();
+                                if (r >= 0) {
+                                        log_close_journal();
+                                        log_close_console();
+                                        return r;
+                                }
+                        }
+                }
+
+                if (IN_SET(log_target, LOG_TARGET_AUTO,
+                                       LOG_TARGET_JOURNAL_OR_KMSG,
+                                       LOG_TARGET_SYSLOG_OR_KMSG,
+                                       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();
+
+        return log_open_console();
+}
+
+void log_set_target(LogTarget target) {
+        assert(target >= 0);
+        assert(target < _LOG_TARGET_MAX);
+
+        if (upgrade_syslog_to_journal) {
+                if (target == LOG_TARGET_SYSLOG)
+                        target = LOG_TARGET_JOURNAL;
+                else if (target == LOG_TARGET_SYSLOG_OR_KMSG)
+                        target = LOG_TARGET_JOURNAL_OR_KMSG;
+        }
+
+        log_target = target;
+}
+
+void log_close(void) {
+        /* Do not call from library code. */
+
+        log_close_journal();
+        log_close_syslog();
+        log_close_kmsg();
+        log_close_console();
+}
+
+void log_forget_fds(void) {
+        /* Do not call from library code. */
+
+        console_fd = kmsg_fd = syslog_fd = journal_fd = -1;
+}
+
+void log_set_max_level_realm(LogRealm realm, int level) {
+        assert((level & LOG_PRIMASK) == level);
+        assert(realm < ELEMENTSOF(log_max_level));
+
+        log_max_level[realm] = level;
+}
+
+void log_set_facility(int facility) {
+        log_facility = facility;
+}
+
+static int write_to_console(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *buffer) {
+
+        char location[256],
+             header_time[FORMAT_TIMESTAMP_MAX],
+             prefix[1 + DECIMAL_STR_MAX(int) + 2],
+             tid_string[3 + DECIMAL_STR_MAX(pid_t) + 1];
+        struct iovec iovec[9];
+        const char *on = NULL, *off = NULL;
+        size_t n = 0;
+
+        if (console_fd < 0)
+                return 0;
+
+        if (log_target == LOG_TARGET_CONSOLE_PREFIXED) {
+                xsprintf(prefix, "<%i>", level);
+                iovec[n++] = IOVEC_MAKE_STRING(prefix);
+        }
+
+        if (show_time) {
+                if (format_timestamp(header_time, sizeof(header_time), now(CLOCK_REALTIME))) {
+                        iovec[n++] = IOVEC_MAKE_STRING(header_time);
+                        iovec[n++] = IOVEC_MAKE_STRING(" ");
+                }
+        }
+
+        if (show_tid) {
+                xsprintf(tid_string, "(" PID_FMT ") ", gettid());
+                iovec[n++] = IOVEC_MAKE_STRING(tid_string);
+        }
+
+        if (show_color)
+                get_log_colors(LOG_PRI(level), &on, &off, NULL);
+
+        if (show_location) {
+                const char *lon = "", *loff = "";
+                if (show_color) {
+                        lon = ANSI_HIGHLIGHT_YELLOW4;
+                        loff = ANSI_NORMAL;
+                }
+
+                (void) snprintf(location, sizeof location, "%s%s:%i%s: ", lon, file, line, loff);
+                iovec[n++] = IOVEC_MAKE_STRING(location);
+        }
+
+        if (on)
+                iovec[n++] = IOVEC_MAKE_STRING(on);
+        iovec[n++] = IOVEC_MAKE_STRING(buffer);
+        if (off)
+                iovec[n++] = IOVEC_MAKE_STRING(off);
+        iovec[n++] = IOVEC_MAKE_STRING("\n");
+
+        if (writev(console_fd, iovec, n) < 0) {
+
+                if (errno == EIO && getpid_cached() == 1) {
+
+                        /* If somebody tried to kick us from our console tty (via vhangup() or suchlike), try
+                         * to reconnect. */
+
+                        log_close_console();
+                        (void) log_open_console();
+                        if (console_fd < 0)
+                                return 0;
+
+                        if (writev(console_fd, iovec, n) < 0)
+                                return -errno;
+                } else
+                        return -errno;
+        }
+
+        return 1;
+}
+
+static int write_to_syslog(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *buffer) {
+
+        char header_priority[2 + DECIMAL_STR_MAX(int) + 1],
+             header_time[64],
+             header_pid[4 + DECIMAL_STR_MAX(pid_t) + 1];
+        struct iovec iovec[5] = {};
+        struct msghdr msghdr = {
+                .msg_iov = iovec,
+                .msg_iovlen = ELEMENTSOF(iovec),
+        };
+        time_t t;
+        struct tm tm;
+
+        if (syslog_fd < 0)
+                return 0;
+
+        xsprintf(header_priority, "<%i>", level);
+
+        t = (time_t) (now(CLOCK_REALTIME) / USEC_PER_SEC);
+        if (!localtime_r(&t, &tm))
+                return -EINVAL;
+
+        if (strftime(header_time, sizeof(header_time), "%h %e %T ", &tm) <= 0)
+                return -EINVAL;
+
+        xsprintf(header_pid, "["PID_FMT"]: ", getpid_cached());
+
+        iovec[0] = IOVEC_MAKE_STRING(header_priority);
+        iovec[1] = IOVEC_MAKE_STRING(header_time);
+        iovec[2] = IOVEC_MAKE_STRING(program_invocation_short_name);
+        iovec[3] = IOVEC_MAKE_STRING(header_pid);
+        iovec[4] = IOVEC_MAKE_STRING(buffer);
+
+        /* When using syslog via SOCK_STREAM separate the messages by NUL chars */
+        if (syslog_is_stream)
+                iovec[4].iov_len++;
+
+        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,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *buffer) {
+
+        /* Set a ratelimit on the amount of messages logged to /dev/kmsg. This is mostly supposed to be a
+         * safety catch for the case where start indiscriminately logging in a loop. It will not catch cases
+         * where we log excessively, but not in a tight loop.
+         *
+         * Note that this ratelimit is per-emitter, so we might still overwhelm /dev/kmsg with multiple
+         * loggers.
+         */
+        static thread_local RateLimit ratelimit = { 5 * USEC_PER_SEC, 200 };
+
+        char header_priority[2 + DECIMAL_STR_MAX(int) + 1],
+             header_pid[4 + DECIMAL_STR_MAX(pid_t) + 1];
+        struct iovec iovec[5] = {};
+
+        if (kmsg_fd < 0)
+                return 0;
+
+        if (!ratelimit_below(&ratelimit))
+                return 0;
+
+        xsprintf(header_priority, "<%i>", level);
+        xsprintf(header_pid, "["PID_FMT"]: ", getpid_cached());
+
+        iovec[0] = IOVEC_MAKE_STRING(header_priority);
+        iovec[1] = IOVEC_MAKE_STRING(program_invocation_short_name);
+        iovec[2] = IOVEC_MAKE_STRING(header_pid);
+        iovec[3] = IOVEC_MAKE_STRING(buffer);
+        iovec[4] = IOVEC_MAKE_STRING("\n");
+
+        if (writev(kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0)
+                return -errno;
+
+        return 1;
+}
+
+static int log_do_header(
+                char *header,
+                size_t size,
+                int level,
+                int error,
+                const char *file, int line, const char *func,
+                const char *object_field, const char *object,
+                const char *extra_field, const char *extra) {
+        int r;
+
+        error = IS_SYNTHETIC_ERRNO(error) ? 0 : ERRNO_VALUE(error);
+
+        r = snprintf(header, size,
+                     "PRIORITY=%i\n"
+                     "SYSLOG_FACILITY=%i\n"
+                     "TID=" PID_FMT "\n"
+                     "%s%.256s%s"        /* CODE_FILE */
+                     "%s%.*i%s"          /* CODE_LINE */
+                     "%s%.256s%s"        /* CODE_FUNC */
+                     "%s%.*i%s"          /* ERRNO */
+                     "%s%.256s%s"        /* object */
+                     "%s%.256s%s"        /* extra */
+                     "SYSLOG_IDENTIFIER=%.256s\n",
+                     LOG_PRI(level),
+                     LOG_FAC(level),
+                     gettid(),
+                     isempty(file) ? "" : "CODE_FILE=",
+                     isempty(file) ? "" : file,
+                     isempty(file) ? "" : "\n",
+                     line ? "CODE_LINE=" : "",
+                     line ? 1 : 0, line, /* %.0d means no output too, special case for 0 */
+                     line ? "\n" : "",
+                     isempty(func) ? "" : "CODE_FUNC=",
+                     isempty(func) ? "" : func,
+                     isempty(func) ? "" : "\n",
+                     error ? "ERRNO=" : "",
+                     error ? 1 : 0, error,
+                     error ? "\n" : "",
+                     isempty(object) ? "" : object_field,
+                     isempty(object) ? "" : object,
+                     isempty(object) ? "" : "\n",
+                     isempty(extra) ? "" : extra_field,
+                     isempty(extra) ? "" : extra,
+                     isempty(extra) ? "" : "\n",
+                     program_invocation_short_name);
+        assert_raw((size_t) r < size);
+
+        return 0;
+}
+
+static int write_to_journal(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *object_field,
+                const char *object,
+                const char *extra_field,
+                const char *extra,
+                const char *buffer) {
+
+        char header[LINE_MAX];
+        struct iovec iovec[4] = {};
+        struct msghdr mh = {};
+
+        if (journal_fd < 0)
+                return 0;
+
+        log_do_header(header, sizeof(header), level, error, file, line, func, object_field, object, extra_field, extra);
+
+        iovec[0] = IOVEC_MAKE_STRING(header);
+        iovec[1] = IOVEC_MAKE_STRING("MESSAGE=");
+        iovec[2] = IOVEC_MAKE_STRING(buffer);
+        iovec[3] = IOVEC_MAKE_STRING("\n");
+
+        mh.msg_iov = iovec;
+        mh.msg_iovlen = ELEMENTSOF(iovec);
+
+        if (sendmsg(journal_fd, &mh, MSG_NOSIGNAL) < 0)
+                return -errno;
+
+        return 1;
+}
+
+int log_dispatch_internal(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *object_field,
+                const char *object,
+                const char *extra_field,
+                const char *extra,
+                char *buffer) {
+
+        assert_raw(buffer);
+
+        if (log_target == LOG_TARGET_NULL)
+                return -ERRNO_VALUE(error);
+
+        /* Patch in LOG_DAEMON facility if necessary */
+        if ((level & LOG_FACMASK) == 0)
+                level |= log_facility;
+
+        if (open_when_needed)
+                (void) log_open();
+
+        do {
+                char *e;
+                int k = 0;
+
+                buffer += strspn(buffer, NEWLINE);
+
+                if (buffer[0] == 0)
+                        break;
+
+                if ((e = strpbrk(buffer, NEWLINE)))
+                        *(e++) = 0;
+
+                if (IN_SET(log_target, LOG_TARGET_AUTO,
+                                       LOG_TARGET_JOURNAL_OR_KMSG,
+                                       LOG_TARGET_JOURNAL)) {
+
+                        k = write_to_journal(level, error, file, line, func, object_field, object, extra_field, extra, buffer);
+                        if (k < 0 && k != -EAGAIN)
+                                log_close_journal();
+                }
+
+                if (IN_SET(log_target, LOG_TARGET_SYSLOG_OR_KMSG,
+                                       LOG_TARGET_SYSLOG)) {
+
+                        k = write_to_syslog(level, error, file, line, func, buffer);
+                        if (k < 0 && k != -EAGAIN)
+                                log_close_syslog();
+                }
+
+                if (k <= 0 &&
+                    IN_SET(log_target, LOG_TARGET_AUTO,
+                                       LOG_TARGET_SYSLOG_OR_KMSG,
+                                       LOG_TARGET_JOURNAL_OR_KMSG,
+                                       LOG_TARGET_KMSG)) {
+
+                        if (k < 0)
+                                log_open_kmsg();
+
+                        k = write_to_kmsg(level, error, file, line, func, buffer);
+                        if (k < 0) {
+                                log_close_kmsg();
+                                (void) log_open_console();
+                        }
+                }
+
+                if (k <= 0)
+                        (void) write_to_console(level, error, file, line, func, buffer);
+
+                buffer = e;
+        } while (buffer);
+
+        if (open_when_needed)
+                log_close();
+
+        return -ERRNO_VALUE(error);
+}
+
+int log_dump_internal(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                char *buffer) {
+
+        LogRealm realm = LOG_REALM_REMOVE_LEVEL(level);
+        PROTECT_ERRNO;
+
+        /* This modifies the buffer... */
+
+        if (_likely_(LOG_PRI(level) > log_max_level[realm]))
+                return -ERRNO_VALUE(error);
+
+        return log_dispatch_internal(level, error, file, line, func, NULL, NULL, NULL, NULL, buffer);
+}
+
+int log_internalv_realm(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *format,
+                va_list ap) {
+
+        LogRealm realm = LOG_REALM_REMOVE_LEVEL(level);
+        char buffer[LINE_MAX];
+        PROTECT_ERRNO;
+
+        if (_likely_(LOG_PRI(level) > log_max_level[realm]))
+                return -ERRNO_VALUE(error);
+
+        /* Make sure that %m maps to the specified error (or "Success"). */
+        errno = ERRNO_VALUE(error);
+
+        (void) vsnprintf(buffer, sizeof buffer, format, ap);
+
+        return log_dispatch_internal(level, error, file, line, func, NULL, NULL, NULL, NULL, buffer);
+}
+
+int log_internal_realm(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *format, ...) {
+
+        va_list ap;
+        int r;
+
+        va_start(ap, format);
+        r = log_internalv_realm(level, error, file, line, func, format, ap);
+        va_end(ap);
+
+        return r;
+}
+
+int log_object_internalv(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *object_field,
+                const char *object,
+                const char *extra_field,
+                const char *extra,
+                const char *format,
+                va_list ap) {
+
+        PROTECT_ERRNO;
+        char *buffer, *b;
+
+        if (_likely_(LOG_PRI(level) > log_max_level[LOG_REALM_SYSTEMD]))
+                return -ERRNO_VALUE(error);
+
+        /* Make sure that %m maps to the specified error (or "Success"). */
+        errno = ERRNO_VALUE(error);
+
+        /* Prepend the object name before the message */
+        if (object) {
+                size_t n;
+
+                n = strlen(object);
+                buffer = newa(char, n + 2 + LINE_MAX);
+                b = stpcpy(stpcpy(buffer, object), ": ");
+        } else
+                b = buffer = newa(char, LINE_MAX);
+
+        (void) vsnprintf(b, LINE_MAX, format, ap);
+
+        return log_dispatch_internal(level, error, file, line, func,
+                                     object_field, object, extra_field, extra, buffer);
+}
+
+int log_object_internal(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *object_field,
+                const char *object,
+                const char *extra_field,
+                const char *extra,
+                const char *format, ...) {
+
+        va_list ap;
+        int r;
+
+        va_start(ap, format);
+        r = log_object_internalv(level, error, file, line, func, object_field, object, extra_field, extra, format, ap);
+        va_end(ap);
+
+        return r;
+}
+
+static void log_assert(
+                int level,
+                const char *text,
+                const char *file,
+                int line,
+                const char *func,
+                const char *format) {
+
+        static char buffer[LINE_MAX];
+        LogRealm realm = LOG_REALM_REMOVE_LEVEL(level);
+
+        if (_likely_(LOG_PRI(level) > log_max_level[realm]))
+                return;
+
+        DISABLE_WARNING_FORMAT_NONLITERAL;
+        (void) snprintf(buffer, sizeof buffer, format, text, file, line, func);
+        REENABLE_WARNING;
+
+        log_abort_msg = buffer;
+
+        log_dispatch_internal(level, 0, file, line, func, NULL, NULL, NULL, NULL, buffer);
+}
+
+_noreturn_ void log_assert_failed_realm(
+                LogRealm realm,
+                const char *text,
+                const char *file,
+                int line,
+                const char *func) {
+        log_assert(LOG_REALM_PLUS_LEVEL(realm, LOG_CRIT), text, file, line, func,
+                   "Assertion '%s' failed at %s:%u, function %s(). Aborting.");
+        abort();
+}
+
+_noreturn_ void log_assert_failed_unreachable_realm(
+                LogRealm realm,
+                const char *text,
+                const char *file,
+                int line,
+                const char *func) {
+        log_assert(LOG_REALM_PLUS_LEVEL(realm, LOG_CRIT), text, file, line, func,
+                   "Code should not be reached '%s' at %s:%u, function %s(). Aborting.");
+        abort();
+}
+
+void log_assert_failed_return_realm(
+                LogRealm realm,
+                const char *text,
+                const char *file,
+                int line,
+                const char *func) {
+        PROTECT_ERRNO;
+        log_assert(LOG_REALM_PLUS_LEVEL(realm, LOG_DEBUG), text, file, line, func,
+                   "Assertion '%s' failed at %s:%u, function %s(). Ignoring.");
+}
+
+int log_oom_internal(LogRealm realm, const char *file, int line, const char *func) {
+        return log_internal_realm(LOG_REALM_PLUS_LEVEL(realm, LOG_ERR),
+                                  ENOMEM, file, line, func, "Out of memory.");
+}
+
+int log_format_iovec(
+                struct iovec *iovec,
+                size_t iovec_len,
+                size_t *n,
+                bool newline_separator,
+                int error,
+                const char *format,
+                va_list ap) {
+
+        static const char nl = '\n';
+
+        while (format && *n + 1 < iovec_len) {
+                va_list aq;
+                char *m;
+                int r;
+
+                /* We need to copy the va_list structure,
+                 * since vasprintf() leaves it afterwards at
+                 * an undefined location */
+
+                errno = ERRNO_VALUE(error);
+
+                va_copy(aq, ap);
+                r = vasprintf(&m, format, aq);
+                va_end(aq);
+                if (r < 0)
+                        return -EINVAL;
+
+                /* Now, jump enough ahead, so that we point to
+                 * the next format string */
+                VA_FORMAT_ADVANCE(format, ap);
+
+                iovec[(*n)++] = IOVEC_MAKE_STRING(m);
+
+                if (newline_separator) {
+                        iovec[*n] = IOVEC_MAKE((char *)&nl, 1);
+                        (*n)++;
+                }
+
+                format = va_arg(ap, char *);
+        }
+        return 0;
+}
+
+int log_struct_internal(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *format, ...) {
+
+        LogRealm realm = LOG_REALM_REMOVE_LEVEL(level);
+        char buf[LINE_MAX];
+        bool found = false;
+        PROTECT_ERRNO;
+        va_list ap;
+
+        if (_likely_(LOG_PRI(level) > log_max_level[realm]) ||
+            log_target == LOG_TARGET_NULL)
+                return -ERRNO_VALUE(error);
+
+        if ((level & LOG_FACMASK) == 0)
+                level |= log_facility;
+
+        if (IN_SET(log_target,
+                   LOG_TARGET_AUTO,
+                   LOG_TARGET_JOURNAL_OR_KMSG,
+                   LOG_TARGET_JOURNAL)) {
+
+                if (open_when_needed)
+                        log_open_journal();
+
+                if (journal_fd >= 0) {
+                        char header[LINE_MAX];
+                        struct iovec iovec[17] = {};
+                        size_t n = 0, i;
+                        int r;
+                        struct msghdr mh = {
+                                .msg_iov = iovec,
+                        };
+                        bool fallback = false;
+
+                        /* If the journal is available do structured logging.
+                         * Do not report the errno if it is synthetic. */
+                        log_do_header(header, sizeof(header), level, error, file, line, func, NULL, NULL, NULL, NULL);
+                        iovec[n++] = IOVEC_MAKE_STRING(header);
+
+                        va_start(ap, format);
+                        r = log_format_iovec(iovec, ELEMENTSOF(iovec), &n, true, error, format, ap);
+                        if (r < 0)
+                                fallback = true;
+                        else {
+                                mh.msg_iovlen = n;
+                                (void) sendmsg(journal_fd, &mh, MSG_NOSIGNAL);
+                        }
+
+                        va_end(ap);
+                        for (i = 1; i < n; i += 2)
+                                free(iovec[i].iov_base);
+
+                        if (!fallback) {
+                                if (open_when_needed)
+                                        log_close();
+
+                                return -ERRNO_VALUE(error);
+                        }
+                }
+        }
+
+        /* Fallback if journal logging is not available or didn't work. */
+
+        va_start(ap, format);
+        while (format) {
+                va_list aq;
+
+                errno = ERRNO_VALUE(error);
+
+                va_copy(aq, ap);
+                (void) vsnprintf(buf, sizeof buf, format, aq);
+                va_end(aq);
+
+                if (startswith(buf, "MESSAGE=")) {
+                        found = true;
+                        break;
+                }
+
+                VA_FORMAT_ADVANCE(format, ap);
+
+                format = va_arg(ap, char *);
+        }
+        va_end(ap);
+
+        if (!found) {
+                if (open_when_needed)
+                        log_close();
+
+                return -ERRNO_VALUE(error);
+        }
+
+        return log_dispatch_internal(level, error, file, line, func, NULL, NULL, NULL, NULL, buf + 8);
+}
+
+int log_struct_iovec_internal(
+                int level,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const struct iovec input_iovec[],
+                size_t n_input_iovec) {
+
+        LogRealm realm = LOG_REALM_REMOVE_LEVEL(level);
+        PROTECT_ERRNO;
+        size_t i;
+        char *m;
+
+        if (_likely_(LOG_PRI(level) > log_max_level[realm]) ||
+            log_target == LOG_TARGET_NULL)
+                return -ERRNO_VALUE(error);
+
+        if ((level & LOG_FACMASK) == 0)
+                level |= log_facility;
+
+        if (IN_SET(log_target, LOG_TARGET_AUTO,
+                               LOG_TARGET_JOURNAL_OR_KMSG,
+                               LOG_TARGET_JOURNAL) &&
+            journal_fd >= 0) {
+
+                struct iovec iovec[1 + n_input_iovec*2];
+                char header[LINE_MAX];
+                struct msghdr mh = {
+                        .msg_iov = iovec,
+                        .msg_iovlen = 1 + n_input_iovec*2,
+                };
+
+                log_do_header(header, sizeof(header), level, error, file, line, func, NULL, NULL, NULL, NULL);
+                iovec[0] = IOVEC_MAKE_STRING(header);
+
+                for (i = 0; i < n_input_iovec; i++) {
+                        iovec[1+i*2] = input_iovec[i];
+                        iovec[1+i*2+1] = IOVEC_MAKE_STRING("\n");
+                }
+
+                if (sendmsg(journal_fd, &mh, MSG_NOSIGNAL) >= 0)
+                        return -ERRNO_VALUE(error);
+        }
+
+        for (i = 0; i < n_input_iovec; i++)
+                if (memory_startswith(input_iovec[i].iov_base, input_iovec[i].iov_len, "MESSAGE="))
+                        break;
+
+        if (_unlikely_(i >= n_input_iovec)) /* Couldn't find MESSAGE=? */
+                return -ERRNO_VALUE(error);
+
+        m = strndupa(input_iovec[i].iov_base + STRLEN("MESSAGE="),
+                     input_iovec[i].iov_len - STRLEN("MESSAGE="));
+
+        return log_dispatch_internal(level, error, file, line, func, NULL, NULL, NULL, NULL, m);
+}
+
+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_realm(LogRealm realm, const char *e) {
+        int t;
+
+        t = log_level_from_string(e);
+        if (t < 0)
+                return -EINVAL;
+
+        log_set_max_level_realm(realm, t);
+        return 0;
+}
+
+static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
+
+        /*
+         * The systemd.log_xyz= settings are parsed by all tools, and
+         * so is "debug".
+         *
+         * However, "quiet" is only parsed by PID 1, and only turns of
+         * status output to /dev/console, but does not alter the log
+         * level.
+         */
+
+        if (streq(key, "debug") && !value)
+                log_set_max_level(LOG_DEBUG);
+
+        else if (proc_cmdline_key_streq(key, "systemd.log_target")) {
+
+                if (proc_cmdline_value_missing(key, value))
+                        return 0;
+
+                if (log_set_target_from_string(value) < 0)
+                        log_warning("Failed to parse log target '%s'. Ignoring.", value);
+
+        } else if (proc_cmdline_key_streq(key, "systemd.log_level")) {
+
+                if (proc_cmdline_value_missing(key, value))
+                        return 0;
+
+                if (log_set_max_level_from_string(value) < 0)
+                        log_warning("Failed to parse log level '%s'. Ignoring.", value);
+
+        } else if (proc_cmdline_key_streq(key, "systemd.log_color")) {
+
+                if (log_show_color_from_string(value ?: "1") < 0)
+                        log_warning("Failed to parse log color setting '%s'. Ignoring.", value);
+
+        } else if (proc_cmdline_key_streq(key, "systemd.log_location")) {
+
+                if (log_show_location_from_string(value ?: "1") < 0)
+                        log_warning("Failed to parse log location setting '%s'. Ignoring.", value);
+
+        } else if (proc_cmdline_key_streq(key, "systemd.log_tid")) {
+
+                if (log_show_tid_from_string(value ?: "1") < 0)
+                        log_warning("Failed to parse log tid setting '%s'. Ignoring.", value);
+
+        } else if (proc_cmdline_key_streq(key, "systemd.log_time")) {
+
+                if (log_show_time_from_string(value ?: "1") < 0)
+                        log_warning("Failed to parse log time setting '%s'. Ignoring.", value);
+
+        }
+
+        return 0;
+}
+
+void log_parse_environment_realm(LogRealm realm) {
+        if (getpid_cached() == 1 || get_ctty_devnr(0, NULL) < 0)
+                /* Only try to read the command line in daemons. We assume that anything that has a
+                 * controlling tty is user stuff. For PID1 we do a special check in case it hasn't
+                 * closed the console yet. */
+                (void) proc_cmdline_parse(parse_proc_cmdline_item, NULL, PROC_CMDLINE_STRIP_RD_PREFIX);
+
+        log_parse_environment_cli_realm(realm);
+}
+
+void log_parse_environment_cli_realm(LogRealm realm) {
+        /* Do not call from library code. */
+
+        const char *e;
+
+        e = getenv("SYSTEMD_LOG_TARGET");
+        if (e && log_set_target_from_string(e) < 0)
+                log_warning("Failed to parse log target '%s'. Ignoring.", e);
+
+        e = getenv("SYSTEMD_LOG_LEVEL");
+        if (e && log_set_max_level_from_string_realm(realm, e) < 0)
+                log_warning("Failed to parse log level '%s'. Ignoring.", e);
+
+        e = getenv("SYSTEMD_LOG_COLOR");
+        if (e && log_show_color_from_string(e) < 0)
+                log_warning("Failed to parse log color '%s'. Ignoring.", e);
+
+        e = getenv("SYSTEMD_LOG_LOCATION");
+        if (e && log_show_location_from_string(e) < 0)
+                log_warning("Failed to parse log location '%s'. Ignoring.", e);
+
+        e = getenv("SYSTEMD_LOG_TIME");
+        if (e && log_show_time_from_string(e) < 0)
+                log_warning("Failed to parse log time '%s'. Ignoring.", e);
+
+        e = getenv("SYSTEMD_LOG_TID");
+        if (e && log_show_tid_from_string(e) < 0)
+                log_warning("Failed to parse log tid '%s'. Ignoring.", e);
+}
+
+LogTarget log_get_target(void) {
+        return log_target;
+}
+
+int log_get_max_level_realm(LogRealm realm) {
+        return log_max_level[realm];
+}
+
+void log_show_color(bool b) {
+        show_color = b;
+}
+
+bool log_get_show_color(void) {
+        return show_color;
+}
+
+void log_show_location(bool b) {
+        show_location = b;
+}
+
+bool log_get_show_location(void) {
+        return show_location;
+}
+
+void log_show_time(bool b) {
+        show_time = b;
+}
+
+bool log_get_show_time(void) {
+        return show_time;
+}
+
+void log_show_tid(bool b) {
+        show_tid = b;
+}
+
+bool log_get_show_tid(void) {
+        return show_tid;
+}
+
+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;
+}
+
+int log_show_time_from_string(const char *e) {
+        int t;
+
+        t = parse_boolean(e);
+        if (t < 0)
+                return t;
+
+        log_show_time(t);
+        return 0;
+}
+
+int log_show_tid_from_string(const char *e) {
+        int t;
+
+        t = parse_boolean(e);
+        if (t < 0)
+                return t;
+
+        log_show_tid(t);
+        return 0;
+}
+
+bool log_on_console(void) {
+        if (IN_SET(log_target, LOG_TARGET_CONSOLE,
+                               LOG_TARGET_CONSOLE_PREFIXED))
+                return true;
+
+        return syslog_fd < 0 && kmsg_fd < 0 && journal_fd < 0;
+}
+
+static const char *const log_target_table[_LOG_TARGET_MAX] = {
+        [LOG_TARGET_CONSOLE] = "console",
+        [LOG_TARGET_CONSOLE_PREFIXED] = "console-prefixed",
+        [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);
+
+void log_received_signal(int level, const struct signalfd_siginfo *si) {
+        assert(si);
+
+        if (pid_is_valid(si->ssi_pid)) {
+                _cleanup_free_ char *p = NULL;
+
+                (void) get_process_comm(si->ssi_pid, &p);
+
+                log_full(level,
+                         "Received SIG%s from PID %"PRIu32" (%s).",
+                         signal_to_string(si->ssi_signo),
+                         si->ssi_pid, strna(p));
+        } else
+                log_full(level,
+                         "Received SIG%s.",
+                         signal_to_string(si->ssi_signo));
+}
+
+int log_syntax_internal(
+                const char *unit,
+                int level,
+                const char *config_file,
+                unsigned config_line,
+                int error,
+                const char *file,
+                int line,
+                const char *func,
+                const char *format, ...) {
+
+        PROTECT_ERRNO;
+        char buffer[LINE_MAX];
+        va_list ap;
+        const char *unit_fmt = NULL;
+
+        if (_likely_(LOG_PRI(level) > log_max_level[LOG_REALM_SYSTEMD]) ||
+            log_target == LOG_TARGET_NULL)
+                return -ERRNO_VALUE(error);
+
+        errno = ERRNO_VALUE(error);
+
+        va_start(ap, format);
+        (void) vsnprintf(buffer, sizeof buffer, format, ap);
+        va_end(ap);
+
+        if (unit)
+                unit_fmt = getpid_cached() == 1 ? "UNIT=%s" : "USER_UNIT=%s";
+
+        if (config_file) {
+                if (config_line > 0)
+                        return log_struct_internal(
+                                        LOG_REALM_PLUS_LEVEL(LOG_REALM_SYSTEMD, level),
+                                        error,
+                                        file, line, func,
+                                        "MESSAGE_ID=" SD_MESSAGE_INVALID_CONFIGURATION_STR,
+                                        "CONFIG_FILE=%s", config_file,
+                                        "CONFIG_LINE=%u", config_line,
+                                        LOG_MESSAGE("%s:%u: %s", config_file, config_line, buffer),
+                                        unit_fmt, unit,
+                                        NULL);
+                else
+                        return log_struct_internal(
+                                        LOG_REALM_PLUS_LEVEL(LOG_REALM_SYSTEMD, level),
+                                        error,
+                                        file, line, func,
+                                        "MESSAGE_ID=" SD_MESSAGE_INVALID_CONFIGURATION_STR,
+                                        "CONFIG_FILE=%s", config_file,
+                                        LOG_MESSAGE("%s: %s", config_file, buffer),
+                                        unit_fmt, unit,
+                                        NULL);
+        } else if (unit)
+                return log_struct_internal(
+                                LOG_REALM_PLUS_LEVEL(LOG_REALM_SYSTEMD, level),
+                                error,
+                                file, line, func,
+                                "MESSAGE_ID=" SD_MESSAGE_INVALID_CONFIGURATION_STR,
+                                LOG_MESSAGE("%s: %s", unit, buffer),
+                                unit_fmt, unit,
+                                NULL);
+        else
+                return log_struct_internal(
+                                LOG_REALM_PLUS_LEVEL(LOG_REALM_SYSTEMD, level),
+                                error,
+                                file, line, func,
+                                "MESSAGE_ID=" SD_MESSAGE_INVALID_CONFIGURATION_STR,
+                                LOG_MESSAGE("%s", buffer),
+                                NULL);
+}
+
+int log_syntax_invalid_utf8_internal(
+                const char *unit,
+                int level,
+                const char *config_file,
+                unsigned config_line,
+                const char *file,
+                int line,
+                const char *func,
+                const char *rvalue) {
+
+        _cleanup_free_ char *p = NULL;
+
+        if (rvalue)
+                p = utf8_escape_invalid(rvalue);
+
+        log_syntax_internal(unit, level, config_file, config_line, 0, file, line, func,
+                            "String is not UTF-8 clean, ignoring assignment: %s", strna(p));
+
+        return -EINVAL;
+}
+
+void log_set_upgrade_syslog_to_journal(bool b) {
+        upgrade_syslog_to_journal = b;
+
+        /* Make the change effective immediately */
+        if (b) {
+                if (log_target == LOG_TARGET_SYSLOG)
+                        log_target = LOG_TARGET_JOURNAL;
+                else if (log_target == LOG_TARGET_SYSLOG_OR_KMSG)
+                        log_target = LOG_TARGET_JOURNAL_OR_KMSG;
+        }
+}
+
+void log_set_always_reopen_console(bool b) {
+        always_reopen_console = b;
+}
+
+void log_set_open_when_needed(bool b) {
+        open_when_needed = b;
+}
+
+void log_set_prohibit_ipc(bool b) {
+        prohibit_ipc = b;
+}
+
+int log_emergency_level(void) {
+        /* Returns the log level to use for log_emergency() logging. We use LOG_EMERG only when we are PID 1, as only
+         * then the system of the whole system is obviously affected. */
+
+        return getpid_cached() == 1 ? LOG_EMERG : LOG_ERR;
+}
+
+int log_dup_console(void) {
+        int copy;
+
+        /* Duplicate the fd we use for fd logging if it's < 3 and use the copy from now on. This call is useful
+         * whenever we want to continue logging through the original fd, but want to rearrange stderr. */
+
+        if (console_fd >= 3)
+                return 0;
+
+        copy = fcntl(console_fd, F_DUPFD_CLOEXEC, 3);
+        if (copy < 0)
+                return -errno;
+
+        console_fd = copy;
+        return 0;
+}
+
+void log_setup_service(void) {
+        /* Sets up logging the way it is most appropriate for running a program as a service. Note that using this
+         * doesn't make the binary unsuitable for invocation on the command line, as log output will still go to the
+         * terminal if invoked interactively. */
+
+        log_set_target(LOG_TARGET_AUTO);
+        log_parse_environment();
+        (void) log_open();
+}
+
+void log_setup_cli(void) {
+        /* Sets up logging the way it is most appropriate for running a program as a CLI utility. */
+
+        log_show_color(true);
+        log_parse_environment_cli();
+        (void) log_open();
+}