source: asp3_tinet_ecnl_arm/trunk/musl-1.1.18/src/misc/syslog.~c@ 352

#include <stdarg.h>
#include <sys/socket.h>
#include <stdio.h>
#include <unistd.h>
#include <syslog.h>
#include <time.h>
#include <signal.h>
#include <string.h>
#include <pthread.h>
#include <errno.h>
#include <fcntl.h>
#include "libc.h"

static volatile int lock[2];
static char log_ident[32];
static int log_opt;
static int log_facility = LOG_USER;
static int log_mask = 0xff;
static int log_fd = -1;

int setlogmask(int maskpri)
{
        LOCK(lock);
        int ret = log_mask;
        if (maskpri) log_mask = maskpri;
        UNLOCK(lock);
        return ret;
}

static const struct {
        short sun_family;
        char sun_path[9];
} log_addr = {
        AF_UNIX,
        "/dev/log"
};

void closelog(void)
{
        int cs;
        pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
        LOCK(lock);
        close(log_fd);
        log_fd = -1;
        UNLOCK(lock);
        pthread_setcancelstate(cs, 0);
}

static void __openlog()
{
        log_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0);
        if (log_fd >= 0) connect(log_fd, (void *)&log_addr, sizeof log_addr);
}

void openlog(const char *ident, int opt, int facility)
{
        int cs;
        pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
        LOCK(lock);

        if (ident) {
                size_t n = strnlen(ident, sizeof log_ident - 1);
                memcpy(log_ident, ident, n);
                log_ident[n] = 0;
        } else {
                log_ident[0] = 0;
        }
        log_opt = opt;
        log_facility = facility;

        if ((opt & LOG_NDELAY) && log_fd<0) __openlog();

        UNLOCK(lock);
        pthread_setcancelstate(cs, 0);
}

static int is_lost_conn(int e)
{
        return e==ECONNREFUSED || e==ECONNRESET || e==ENOTCONN || e==EPIPE;
}

static void _vsyslog(int priority, const char *message, va_list ap)
{
        char timebuf[16];
        time_t now;
        struct tm tm;
        char buf[1024];
        int errno_save = errno;
        int pid;
        int l, l2;
        int hlen;
        int fd;

        if (log_fd < 0) __openlog();

        if (!(priority & LOG_FACMASK)) priority |= log_facility;

        now = time(NULL);
        gmtime_r(&now, &tm);
        strftime(timebuf, sizeof timebuf, "%b %e %T", &tm);

        pid = (log_opt & LOG_PID) ? getpid() : 0;
        l = snprintf(buf, sizeof buf, "<%d>%s %n%s%s%.0d%s: ",
                priority, timebuf, &hlen, log_ident, "["+!pid, pid, "]"+!pid);
        errno = errno_save;
        l2 = vsnprintf(buf+l, sizeof buf - l, message, ap);
        if (l2 >= 0) {
                if (l2 >= sizeof buf - l) l = sizeof buf - 1;
                else l += l2;
                if (buf[l-1] != '\n') buf[l++] = '\n';
                if (send(log_fd, buf, l, 0) < 0 && (!is_lost_conn(errno)
                    || connect(log_fd, (void *)&log_addr, sizeof log_addr) < 0
                    || send(log_fd, buf, l, 0) < 0)
                    && (log_opt & LOG_CONS)) {
                        fd = open("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC);
                        if (fd >= 0) {
                                dprintf(fd, "%.*s", l-hlen, buf+hlen);
                                close(fd);
                        }
                }
                if (log_opt & LOG_PERROR) dprintf(2, "%.*s", l-hlen, buf+hlen);
        }
}

void __vsyslog(int priority, const char *message, va_list ap)
{
        int cs;
        if (!(log_mask & LOG_MASK(priority&7)) || (priority&~0x3ff)) return;
        pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
        LOCK(lock);
        _vsyslog(priority, message, ap);
        UNLOCK(lock);
        pthread_setcancelstate(cs, 0);
}

void syslog(int priority, const char *message, ...)
{
        va_list ap;
        va_start(ap, message);
        __vsyslog(priority, message, ap);
        va_end(ap);
}

weak_alias(__vsyslog, vsyslog);