fix multiple bugs in syslog interfaces

[musl] / src / misc / syslog.c

diff --git a/src/misc/syslog.c b/src/misc/syslog.c
index de42ce2..ba9cc62 100644 (file)
--- a/src/misc/syslog.c
+++ b/src/misc/syslog.c
@@ -7,20 +7,21 @@
 #include <time.h>
 #include <signal.h>
 #include <string.h>
+#include <pthread.h>
 #include "libc.h"
+#include "atomic.h"
 
-static int lock;
-static const char *log_ident;
+static int lock[2];
+static char log_ident[32];
 static int log_opt;
 static int log_facility = LOG_USER;
 static int log_mask = 0xff;
-static FILE *log_f;
+static int log_fd = -1;
 
 int setlogmask(int maskpri)
 {
-       int old = log_mask;
-       if (maskpri) log_mask = maskpri;
-       return old;
+       if (maskpri) return a_swap(&log_mask, maskpri);
+       else return log_mask;
 }
 
 static const struct {
@@ -33,72 +34,92 @@ static const struct {
 
 void closelog(void)
 {
-       LOCK(&lock);
-       if (log_f) fclose(log_f);
-       log_f = NULL;
-       UNLOCK(&lock);
+       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(const char *ident, int opt, int facility)
+static void __openlog()
 {
-       int fd;
+       log_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0);
+       if (log_fd >= 0) connect(log_fd, (void *)&log_addr, sizeof log_addr);
+}
 
-       log_ident = ident;
+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_f) return;
+       if ((opt & LOG_NDELAY) && log_fd<0) __openlog();
 
-       fd = socket(AF_UNIX, SOCK_DGRAM, 0);
-       fcntl(fd, F_SETFD, FD_CLOEXEC);
-       if (connect(fd, (void *)&log_addr, sizeof(short) + sizeof "/dev/log") < 0)
-               close(fd);
-       else log_f = fdopen(fd, "wb");
+       UNLOCK(lock);
+       pthread_setcancelstate(cs, 0);
 }
 
-void openlog(const char *ident, int opt, int facility)
+static void _vsyslog(int priority, const char *message, va_list ap)
 {
-       LOCK(&lock);
-       __openlog(ident, opt, facility);
-       UNLOCK(&lock);
-}
-
-void syslog(int priority, const char *message, ...)
-{
-       va_list ap;
        char timebuf[16];
        time_t now;
        struct tm tm;
-       //const char *fmt, *ident, *sep;
-       //int i;
-
-       if (!(log_mask & LOG_MASK(priority&7)) || (priority&~0x3ff)) return;
-
-       LOCK(&lock);
+       char buf[256];
+       int pid;
+       int l, l2;
 
-       if (!log_f) __openlog(log_ident, log_opt | LOG_NDELAY, log_facility);
-       if (!log_f) {
-               UNLOCK(&lock);
-               return;
+       if (log_fd < 0) {
+               __openlog();
+               if (log_fd < 0) return;
        }
 
+       if (!(priority & LOG_FACMASK)) priority |= log_facility;
+
        now = time(NULL);
        gmtime_r(&now, &tm);
        strftime(timebuf, sizeof timebuf, "%b %e %T", &tm);
 
-       fprintf(log_f, "<%d>%s ", priority, timebuf);
-       if (log_ident) fprintf(log_f, "%s", log_ident);
-       if (log_opt & LOG_PID) fprintf(log_f, "[%d]", getpid());
-       if (log_ident) fprintf(log_f, ": ");
+       pid = (log_opt & LOG_PID) ? getpid() : 0;
+       l = snprintf(buf, sizeof buf, "<%d>%s %s%s%.0d%s: ",
+               priority, timebuf, log_ident, "["+!pid, pid, "]"+!pid);
+       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';
+               send(log_fd, buf, l, 0);
+       }
+}
+
+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);
-       vfprintf(log_f, message, ap);
+       __vsyslog(priority, message, ap);
        va_end(ap);
-       fputc(0, log_f);
-       fflush(log_f);
-
-       // Note: LOG_CONS is not supported because it is annoying!!
-       // syslogd will send messages to console if it deems them appropriate!
-
-       UNLOCK(&lock);
 }
+
+weak_alias(__vsyslog, vsyslog);