From: Willy Tarreau <w@1wt.eu>
Date: Thu, 28 Aug 2014 13:03:15 +0000 (+0200)
Subject: MINOR: log: add a new field "%lc" to implement a per-frontend log counter
X-Git-Tag: v1.6-dev1~330
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=7346acb6f1c148782ebaa93d34e7b86a7f8706ae;p=thirdparty%2Fhaproxy.git

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/doc/configuration.txt b/doc/configuration.txt
index 90052e3843..516319902a 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -12569,6 +12569,7 @@ Please refer to the table below for currently defined variables :
   |   | %fi  | frontend_ip              (accepting address)  | IP          |
   |   | %fp  | frontend_port            (accepting address)  | numeric     |
   |   | %ft  | frontend_name_transport ('~' suffix for SSL)  | string      |
+  |   | %lc  | frontend_log_counter                          | numeric     |
   |   | %hr  | captured_request_headers default style        | string      |
   |   | %hrl | captured_request_headers CLF style            | string list |
   |   | %hs  | captured_response_headers default style       | string      |
diff --git a/include/types/log.h b/include/types/log.h
index c7e47ea4ad..c680663f34 100644
--- a/include/types/log.h
+++ b/include/types/log.h
@@ -53,6 +53,7 @@ enum {
 	LOG_FMT_SERVERPORT,
 	LOG_FMT_SERVERIP,
 	LOG_FMT_COUNTER,
+	LOG_FMT_LOGCNT,
 	LOG_FMT_PID,
 	LOG_FMT_DATE,
 	LOG_FMT_DATEGMT,
diff --git a/include/types/proxy.h b/include/types/proxy.h
index b31df74f9c..748f4aa884 100644
--- a/include/types/proxy.h
+++ b/include/types/proxy.h
@@ -316,6 +316,8 @@ struct proxy {
 	int (*accept)(struct session *s);       /* application layer's accept() */
 	struct conn_src conn_src;               /* connection source settings */
 	struct proxy *next;
+
+	unsigned int log_count;			/* number of logs produced by the frontend */
 	struct list logsrvs;
 	struct list logformat; 			/* log_format linked list */
 	char *header_unique_id; 		/* unique-id header */
diff --git a/src/log.c b/src/log.c
index 3e3acb4cb2..07981e5b9a 100644
--- a/src/log.c
+++ b/src/log.c
@@ -107,6 +107,7 @@ static const struct logformat_type logformat_keywords[] = {
 	{ "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 @@ int build_logline(struct session *s, char *dst, size_t maxsize, struct list *lis
 				}
 				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 @@ void sess_log(struct session *s)
 	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;
 	}