diff options
| -rw-r--r-- | misc/syslog.c | 86 |
1 files changed, 52 insertions, 34 deletions
diff --git a/misc/syslog.c b/misc/syslog.c index c9db35b8c8..1b18375c95 100644 --- a/misc/syslog.c +++ b/misc/syslog.c @@ -120,12 +120,12 @@ void __vsyslog_internal (int pri, const char *fmt, va_list ap, unsigned int mode_flags) { - FILE *f; - char *buf = 0; + /* Try to use a static buffer as an optimization. */ + char bufs[1024]; + char *buf = NULL; size_t bufsize = 0; int msgoff; int saved_errno = errno; - char failbuf[3 * sizeof (pid_t) + sizeof "out of memory []"]; #define INTERNALLOG LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID /* Check for invalid bits. */ @@ -149,43 +149,61 @@ __vsyslog_internal (int pri, const char *fmt, va_list ap, if ((pri & LOG_FACMASK) == 0) pri |= LogFacility; - /* Build the message in a memory-buffer stream. */ - f = __open_memstream (&buf, &bufsize); - if (f != NULL) + pid_t pid = LogStat & LOG_PID ? __getpid () : 0; + + /* "%b %e %H:%M:%S " */ + char timestamp[sizeof "MMM DD hh:mm:ss "]; + time_t now = time_now (); + struct tm now_tm; + __localtime_r (&now, &now_tm); + __strftime_l (timestamp, sizeof timestamp, "%b %e %T ", &now_tm, + _nl_C_locobj_ptr); + +#define SYSLOG_HEADER(__pri, __timestamp, __msgoff, pid) \ + "<%d>%s %n%s%s%.0d%s: ", \ + __pri, __timestamp, __msgoff, \ + LogTag == NULL ? __progname : LogTag, \ + "[" + (pid == 0), pid, "]" + (pid == 0) + + int l = __snprintf (bufs, sizeof bufs, + SYSLOG_HEADER (pri, timestamp, &msgoff, pid)); + if (0 <= l && l < sizeof bufs) { - __fsetlocking (f, FSETLOCKING_BYCALLER); - /* "%b %e %H:%M:%S" */ - char timebuf[sizeof "MMM DD hh:mm:ss "]; - time_t now = time_now (); - struct tm now_tm; - __localtime_r (&now, &now_tm); - __strftime_l (timebuf, sizeof (timebuf), "%b %e %T", &now_tm, - _nl_C_locobj_ptr); - - pid_t pid = LogStat & LOG_PID ? __getpid () : 0; - - fprintf (f, "<%d>%s %n%s%s%.0d%s: ", pri, timebuf, &msgoff, - LogTag == NULL ? __progname : LogTag, - pid != 0 ? "[" : "", pid, pid != 0 ? "]" : ""); + va_list apc; + va_copy (apc, ap); + /* Restore errno for %m format. */ __set_errno (saved_errno); - /* We have the header. Print the user's format into the buffer. */ - __vfprintf_internal (f, fmt, ap, mode_flags); - - /* Close the memory stream; this will finalize the data into a malloc'd - buffer in BUF. */ - fclose (f); + int vl = __vsnprintf_internal (bufs + l, sizeof bufs - l, fmt, apc, + mode_flags); + if (0 <= vl && vl < sizeof bufs - l) + { + buf = bufs; + bufsize = l + vl; + } - /* Tell the cancellation handler to free this buffer. */ - clarg.buf = buf; + va_end (apc); } - else + + if (buf == NULL) { - /* Nothing much to do but emit an error message. */ - bufsize = __snprintf (failbuf, sizeof failbuf, "out of memory[%d]", - __getpid ()); - buf = failbuf; + buf = malloc (l * sizeof (char)); + if (buf != NULL) + { + /* Tell the cancellation handler to free this buffer. */ + clarg.buf = buf; + + __snprintf (buf, sizeof buf, + SYSLOG_HEADER (pri, timestamp, &msgoff, pid)); + } + else + { + /* Nothing much to do but emit an error message. */ + bufsize = __snprintf (bufs, sizeof bufs, + "out of memory[%d]", __getpid ()); + buf = bufs; + } } /* Output to stderr if requested. */ @@ -236,7 +254,7 @@ out: __libc_cleanup_pop (0); __libc_lock_unlock (syslog_lock); - if (buf != failbuf) + if (buf != bufs) free (buf); } |