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-rw-r--r--src/log.c439
1 files changed, 439 insertions, 0 deletions
diff --git a/src/log.c b/src/log.c
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index 0000000000..5d17955e7e
--- /dev/null
+++ b/src/log.c
@@ -0,0 +1,439 @@
+/*-*- Mode: C; c-basic-offset: 8 -*-*/
+
+/***
+ 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 "log.h"
+#include "util.h"
+#include "macro.h"
+
+#define SYSLOG_TIMEOUT_USEC (5*USEC_PER_SEC)
+#define LOG_BUFFER_MAX 1024
+
+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;
+
+/* 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 (getpid() == 1 || console_fd != STDERR_FILENO) {
+ close_nointr_nofail(console_fd);
+ console_fd = -1;
+ }
+}
+
+static int log_open_console(void) {
+
+ 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) {
+ 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)
+ return;
+
+ close_nointr_nofail(syslog_fd);
+ syslog_fd = -1;
+}
+
+static int log_open_syslog(void) {
+ union {
+ struct sockaddr sa;
+ struct sockaddr_un un;
+ } sa;
+ struct timeval tv;
+ int r;
+
+ if (syslog_fd >= 0)
+ return 0;
+
+ 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;
+ goto fail;
+ }
+
+ zero(sa);
+ sa.un.sun_family = AF_UNIX;
+ strncpy(sa.un.sun_path, "/dev/log", sizeof(sa.un.sun_path));
+
+ if (connect(syslog_fd, &sa.sa, sizeof(sa)) < 0) {
+ r = -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) {
+ assert(target >= 0);
+ assert(target < _LOG_TARGET_MAX);
+
+ log_target = target;
+}
+
+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 *buffer) {
+
+ char location[64];
+ struct iovec iovec[5];
+ unsigned n = 0;
+ bool highlight;
+
+ 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;
+
+ 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>", LOG_MAKEPRI(LOG_DAEMON, LOG_PRI(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), "[%llu]: ", (unsigned long 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], __progname);
+ IOVEC_SET_STRING(iovec[3], header_pid);
+ IOVEC_SET_STRING(iovec[4], buffer);
+
+ zero(msghdr);
+ msghdr.msg_iov = iovec;
+ msghdr.msg_iovlen = ELEMENTSOF(iovec);
+
+ if (sendmsg(syslog_fd, &msghdr, 0) < 0)
+ return -errno;
+
+ 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>", LOG_PRI(level));
+ char_array_0(header_priority);
+
+ snprintf(header_pid, sizeof(header_pid), "[%llu]: ", (unsigned long long) getpid());
+ char_array_0(header_pid);
+
+ 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], "\n");
+
+ if (writev(kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0)
+ return -errno;
+
+ return 1;
+}
+
+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;
+
+ if (_likely(LOG_PRI(level) > log_max_level))
+ return 0;
+
+ saved_errno = errno;
+
+ 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);