MINOR: log: add a new field "%lc" to implement a per-frontend log counter
Sometimes it would be convenient to have a log counter so that from a log
server we know whether some logs were lost or not. The frontend's log counter
serves exactly this purpose. It's incremented each time a traffic log is
produced. If a log is disabled using "http-request set-log-level silent",
the counter will not be incremented. However, admin logs are not accounted
for. Also, if logs are filtered out before being sent to the server because
of a minimum level set on the log line, the counter will be increased anyway.
The counter is 32-bit, so it will wrap, but that's not an issue considering
that 4 billion logs are rarely in the same file, let alone close to each
other.
diff --git a/src/log.c b/src/log.c
index 3e3acb4..07981e5 100644
--- a/src/log.c
+++ b/src/log.c
@@ -107,6 +107,7 @@
{ "hrl", LOG_FMT_HDRREQUESTLIST, PR_MODE_TCP, LW_REQHDR, NULL }, /* header request list */
{ "hs", LOG_FMT_HDRRESPONS, PR_MODE_TCP, LW_RSPHDR, NULL }, /* header response */
{ "hsl", LOG_FMT_HDRRESPONSLIST, PR_MODE_TCP, LW_RSPHDR, NULL }, /* header response list */
+ { "lc", LOG_FMT_LOGCNT, PR_MODE_TCP, LW_INIT, NULL }, /* log counter */
{ "ms", LOG_FMT_MS, PR_MODE_TCP, LW_INIT, NULL }, /* accept date millisecond */
{ "pid", LOG_FMT_PID, PR_MODE_TCP, LW_INIT, NULL }, /* log pid */
{ "r", LOG_FMT_REQ, PR_MODE_HTTP, LW_REQ, NULL }, /* request */
@@ -1530,6 +1531,22 @@
}
break;
+ case LOG_FMT_LOGCNT: // %lc
+ if (tmp->options & LOG_OPT_HEXA) {
+ iret = snprintf(tmplog, dst + maxsize - tmplog, "%04X", s->fe->log_count);
+ if (iret < 0 || iret > dst + maxsize - tmplog)
+ goto out;
+ last_isspace = 0;
+ tmplog += iret;
+ } else {
+ ret = ultoa_o(s->fe->log_count, tmplog, dst + maxsize - tmplog);
+ if (ret == NULL)
+ goto out;
+ tmplog = ret;
+ last_isspace = 0;
+ }
+ break;
+
case LOG_FMT_HOSTNAME: // %H
src = hostname;
ret = lf_text(tmplog, src, dst + maxsize - tmplog, tmp);
@@ -1620,6 +1637,7 @@
size = tmplog - logline;
size += build_logline(s, tmplog, global.max_syslog_len - size, &s->fe->logformat);
if (size > 0) {
+ s->fe->log_count++;
__send_log(s->fe, level, logline, size + 1);
s->logs.logwait = 0;
}