summaryrefslogtreecommitdiff
path: root/src/shared/log.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/shared/log.c')
-rw-r--r--src/shared/log.c579
1 files changed, 579 insertions, 0 deletions
diff --git a/src/shared/log.c b/src/shared/log.c
new file mode 100644
index 0000000000..cd496cf6c5
--- /dev/null
+++ b/src/shared/log.c
@@ -0,0 +1,579 @@
+/*-*- 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 Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser 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 <string.h>
+
+#include "log.h"
+#include "time-util.h"
+#include "util.h"
+#include "missing.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 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)
+ return console_fd;
+ } 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)
+ return -errno;
+
+ 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;
+
+ fd = socket(AF_UNIX, type|SOCK_CLOEXEC, 0);
+ if (fd < 0)
+ return -errno;
+
+ fd_inc_sndbuf(fd, SNDBUF_SIZE);
+
+ return fd;
+}
+
+static int log_open_syslog(void) {
+ int r;
+ union sockaddr_union sa = {
+ .un.sun_family = AF_UNIX,
+ .un.sun_path = "/dev/log",
+ };
+
+ 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, 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;
+
+ return 0;
+
+fail:
+ log_close_syslog();
+ 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_syslog();
+ log_close_console();
+ return 0;
+ }
+
+ if ((log_target != LOG_TARGET_AUTO && log_target != LOG_TARGET_SAFE) ||
+ getpid() == 1 ||
+ isatty(STDERR_FILENO) <= 0) {
+
+ if (log_target == LOG_TARGET_AUTO)
+ 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_console();
+ return r;
+ }
+ }
+
+ if (log_target == LOG_TARGET_AUTO ||
+ log_target == LOG_TARGET_SAFE ||
+ log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
+ log_target == LOG_TARGET_KMSG) {
+ r = log_open_kmsg();
+ if (r >= 0) {
+ log_close_syslog();
+ log_close_console();
+ return r;
+ }
+ }
+ }
+
+ log_close_syslog();
+
+ 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_syslog();
+ log_close_kmsg();
+ log_close_console();
+}
+
+void log_set_max_level(int level) {
+ assert((level & LOG_PRIMASK) == level);
+
+ log_max_level = level;
+}
+
+static int write_to_console(
+ int level,
+ const char*file,
+ int line,
+ const char *func,
+ const char *object_name,
+ const char *object,
+ 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;
+
+ 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) {
+
+ if (errno == EIO && getpid() == 1) {
+
+ /* If somebody tried to kick us from our
+ * console tty (via vhangup() or suchlike),
+ * try to reconnect */
+
+ log_close_console();
+ 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,
+ const char*file,
+ int line,
+ const char *func,
+ const char *object_name,
+ const char *object,
+ const char *buffer) {
+
+ char header_priority[16], header_time[64], header_pid[16];
+ 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;
+
+ snprintf(header_priority, sizeof(header_priority), "<%i>", level);
+ char_array_0(header_priority);
+
+ t = (time_t) (now(CLOCK_REALTIME) / USEC_PER_SEC);
+ tm = localtime(&t);
+ if (!tm)
+ return -EINVAL;
+
+ if (strftime(header_time, sizeof(header_time), "%h %e %T ", tm) <= 0)
+ return -EINVAL;
+
+ snprintf(header_pid, sizeof(header_pid), "["PID_FMT"]: ", getpid());
+ char_array_0(header_pid);
+
+ 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++;
+
+ 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 *object_name,
+ const char *object,
+ 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), "["PID_FMT"]: ", getpid());
+ char_array_0(header_pid);
+
+ 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 log_do_header(char *header, size_t size,
+ int level,
+ const char *file, int line, const char *func,
+ const char *object_name, const char *object) {
+ snprintf(header, size,
+ "PRIORITY=%i\n"
+ "SYSLOG_FACILITY=%i\n"
+ "%s%.*s%s"
+ "%s%.*i%s"
+ "%s%.*s%s"
+ "%s%.*s%s"
+ "SYSLOG_IDENTIFIER=%s\n",
+ LOG_PRI(level),
+ LOG_FAC(level),
+ file ? "CODE_FILE=" : "",
+ file ? LINE_MAX : 0, file, /* %.0s means no output */
+ file ? "\n" : "",
+ line ? "CODE_LINE=" : "",
+ line ? 1 : 0, line, /* %.0d means no output too, special case for 0 */
+ line ? "\n" : "",
+ func ? "CODE_FUNCTION=" : "",
+ func ? LINE_MAX : 0, func,
+ func ? "\n" : "",
+ object ? object_name : "",
+ object ? LINE_MAX : 0, object, /* %.0s means no output */
+ object ? "\n" : "",
+ program_invocation_short_name);
+ header[size - 1] = '\0';
+ return 0;
+}
+
+static int log_dispatch(
+ int level,
+ const char*file,
+ int line,
+ const char *func,
+ const char *object_name,
+ const char *object,
+ 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_open_kmsg();
+
+ if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
+ log_target == LOG_TARGET_SYSLOG) {
+
+ k = write_to_syslog(level, file, line, func,
+ object_name, object, 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_SAFE ||
+ log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
+ log_target == LOG_TARGET_KMSG)) {
+
+ k = write_to_kmsg(level, file, line, func,
+ object_name, object, 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,
+ object_name, object, buffer);
+ if (k < 0)
+ return k;
+ }
+
+ buffer = e;
+ } while (buffer);
+
+ return r;
+}
+
+int log_metav(
+ int level,
+ const char*file,
+ int line,
+ const char *func,
+ const char *format,
+ va_list ap) {
+
+ PROTECT_ERRNO;
+ char buffer[LINE_MAX];
+
+ if (_likely_(LOG_PRI(level) > log_max_level))
+ return 0;
+
+ vsnprintf(buffer, sizeof(buffer), format, ap);
+ char_array_0(buffer);
+
+ return log_dispatch(level, file, line, func, NULL, NULL, buffer);
+}
+
+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;
+}
+
+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];
+
+ if (_likely_(LOG_PRI(level) > log_max_level))
+ return;
+
+ DISABLE_WARNING_FORMAT_NONLITERAL;
+ snprintf(buffer, sizeof(buffer), format, text, file, line, func);
+ REENABLE_WARNING;
+
+ char_array_0(buffer);
+ log_abort_msg = buffer;
+
+ log_dispatch(level, file, line, func, NULL, NULL, buffer);
+}
+
+noreturn void log_assert_failed(const char *text, const char *file, int line, const char *func) {
+ log_assert(LOG_CRIT, text, file, line, func, "Assertion '%s' failed at %s:%u, function %s(). Aborting.");
+ abort();
+}
+
+noreturn void log_assert_failed_unreachable(const char *text, const char *file, int line, const char *func) {
+ log_assert(LOG_CRIT, text, file, line, func, "Code should not be reached '%s' at %s:%u, function %s(). Aborting.");
+ abort();
+}
+
+int log_oom_internal(const char *file, int line, const char *func) {
+ log_meta(LOG_ERR, file, line, func, "Out of memory.");
+ return -ENOMEM;
+}
+
+int log_get_max_level(void) {
+ return log_max_level;
+}
+static const char *const log_target_table[] = {
+ [LOG_TARGET_CONSOLE] = "console",
+ [LOG_TARGET_KMSG] = "kmsg",
+ [LOG_TARGET_SYSLOG] = "syslog",
+ [LOG_TARGET_SYSLOG_OR_KMSG] = "syslog-or-kmsg",
+ [LOG_TARGET_AUTO] = "auto",
+ [LOG_TARGET_SAFE] = "safe",
+ [LOG_TARGET_NULL] = "null"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(log_target, LogTarget);
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-25 16:03:25 +0000