From 16801e901e87f4ca0c83ea8c09df1ab3d344129e Mon Sep 17 00:00:00 2001 From: Lennart Poettering Date: Tue, 6 Apr 2010 21:57:45 +0200 Subject: [PATCH] log: rework logging subsystem to support syslog and kmsg output --- log.c | 234 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-- log.h | 16 +++++ logger.c | 8 +-- 3 files changed, 245 insertions(+), 13 deletions(-) diff --git a/log.c b/log.c index 674b877..da1c4f6 100644 --- a/log.c +++ b/log.c @@ -22,19 +22,121 @@ #include #include #include +#include +#include +#include +#include #include "log.h" +#include "util.h" +#include "macro.h" -void log_meta( +extern char * __progname; + +#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 syslog_fd = -1; +static int kmsg_fd = -1; + +void log_close_kmsg(void) { + + if (kmsg_fd >= 0) { + close_nointr(kmsg_fd); + kmsg_fd = -1; + } +} + +int log_open_kmsg(void) { + + if (log_target != LOG_TARGET_KMSG) { + log_close_kmsg(); + return 0; + } + + if (kmsg_fd >= 0) + return 0; + + if ((kmsg_fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0) + return -errno; + + return 0; +} + +void log_close_syslog(void) { + + if (syslog_fd >= 0) { + close_nointr(syslog_fd); + syslog_fd = -1; + } +} + +int log_open_syslog(void) { + union { + struct sockaddr sa; + struct sockaddr_un un; + } sa; + 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; + + /* 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; + } + + 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; + log_close_syslog(); + return -errno; + } + + return 0; +} + +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 void write_to_console( int level, const char*file, int line, const char *func, - const char *format, ...) { + const char *format, + va_list ap) { const char *prefix, *suffix; - va_list ap; - int saved_errno = errno; if (LOG_PRI(level) <= LOG_ERR) { prefix = "\x1B[1;31m"; @@ -44,13 +146,131 @@ void log_meta( suffix = ""; } - va_start(ap, format); - fprintf(stderr, "(%s:%u) %s", file, line, prefix); vfprintf(stderr, format, ap); fprintf(stderr, "%s\n", suffix); +} - va_end(ap); +static int write_to_syslog( + int level, + const char*file, + int line, + const char *func, + const char *format, + va_list ap) { + + 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; + + 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); + + 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); + IOVEC_SET_STRING(iovec[2], file_name_from_path(__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 0; +} + +static int write_to_kmsg( + int level, + const char*file, + int line, + const char *func, + const char *format, + va_list ap) { + + char header_priority[16], header_pid[16]; + char buffer[LOG_BUFFER_MAX]; + struct iovec iovec[5]; + + if (kmsg_fd < 0) + return -EIO; + + 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); + + vsnprintf(buffer, sizeof(buffer), format, ap); + char_array_0(buffer); + + zero(iovec); + IOVEC_SET_STRING(iovec[0], header_priority); + IOVEC_SET_STRING(iovec[1], file_name_from_path(__progname)); + IOVEC_SET_STRING(iovec[2], header_pid); + IOVEC_SET_STRING(iovec[3], buffer); + IOVEC_SET_STRING(iovec[4], (char*) "\n"); + + if (writev(kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0) + return -errno; + + return 0; +} + +void log_meta( + int level, + const char*file, + int line, + const char *func, + const char *format, ...) { + + va_list ap; + bool written; + int saved_errno; + + if (LOG_PRI(level) > log_max_level) + return; + + 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); + } errno = saved_errno; } diff --git a/log.h b/log.h index 232798a..d6aa472 100644 --- a/log.h +++ b/log.h @@ -26,6 +26,22 @@ #include "macro.h" +typedef enum LogTarget{ + LOG_TARGET_CONSOLE, + LOG_TARGET_SYSLOG, + LOG_TARGET_KMSG, + _LOG_TARGET_MAX, + _LOG_TARGET_INVALID = -1 +} LogTarget; + +void log_set_target(LogTarget target); +void log_set_max_level(int level); + +void log_close_kmsg(void); +int log_open_kmsg(void); +void log_close_syslog(void); +int log_open_syslog(void); + void log_meta( int level, const char*file, diff --git a/logger.c b/logger.c index 46cce5f..7194320 100644 --- a/logger.c +++ b/logger.c @@ -62,11 +62,6 @@ typedef enum StreamState { STREAM_RUNNING } StreamState; -typedef enum LogTarget { - LOG_TARGET_SYSLOG, - LOG_TARGET_KMSG -} LogTarget; - struct Stream { Server *server; @@ -89,7 +84,6 @@ struct Stream { static int stream_log(Stream *s, char *p, usec_t timestamp) { char header_priority[16], header_time[64], header_pid[16]; - struct msghdr msghdr; struct iovec iovec[5]; assert(s); @@ -133,6 +127,8 @@ static int stream_log(Stream *s, char *p, usec_t timestamp) { IOVEC_SET_STRING(iovec[0], header_priority); if (s->target == LOG_TARGET_SYSLOG) { + struct msghdr msghdr; + IOVEC_SET_STRING(iovec[1], header_time); IOVEC_SET_STRING(iovec[2], s->process); IOVEC_SET_STRING(iovec[3], header_pid); -- 2.7.4