* add buf to uwsgi_logger struct and use it when logger needs buffering (rsyslog + graylog2)

* allow to split big syslog messages into chunks
* allow to set maximum syslog packet size (some syslog deamons support that)

core/logging.c

@@ -761,6 +761,7 @@ void uwsgi_register_logger(char *name, ssize_t(*func) (struct uwsgi_logger *, ch
 	ul->configured = 0;
 	ul->fd = -1;
 	ul->data = NULL;
+	ul->buf = NULL;
 
 
 #ifdef UWSGI_DEBUG

plugins/graylog2/graylog2_plugin.c

@@ -10,7 +10,6 @@ struct graylog2_config {
 	char json_buf[MAX_GELF];
 	char escaped_buf[MAX_GELF];
 	size_t escaped_len;
-	char buffer[MAX_GELF];
 } g2c;
 
 ssize_t uwsgi_graylog2_logger(struct uwsgi_logger *ul, char *message, size_t len) {
@@ -52,6 +51,8 @@ ssize_t uwsgi_graylog2_logger(struct uwsgi_logger *ul, char *message, size_t len
 
 		*comma = ',';
 
+		ul->buf = uwsgi_malloc(MAX_GELF);
+
 		ul->configured = 1;
 	}
 
@@ -91,8 +92,8 @@ ssize_t uwsgi_graylog2_logger(struct uwsgi_logger *ul, char *message, size_t len
 
 	if (rlen > 0) {
 		if (compressBound((uLong) rlen) <= MAX_GELF) {
-			if (compress((Bytef *) g2c.buffer, &destLen, (Bytef *) g2c.json_buf, (uLong) rlen) == Z_OK) {
-				return sendto(ul->fd, g2c.buffer, destLen, 0, (const struct sockaddr *) &ul->addr, ul->addr_len);
+			if (compress((Bytef *) ul->buf, &destLen, (Bytef *) g2c.json_buf, (uLong) rlen) == Z_OK) {
+				return sendto(ul->fd, ul->buf, destLen, 0, (const struct sockaddr *) &ul->addr, ul->addr_len);
 			}
 		}
 

plugins/rsyslog/rsyslog_plugin.c

@@ -2,11 +2,23 @@
 
 extern struct uwsgi_server uwsgi;
 
-#define MAX_SYSLOG_PKT 1024
+
+struct uwsgi_rsyslog {
+	int packet_size;
+	int msg_size;
+	int split_msg;
+} u_rsyslog;
+
+
+struct uwsgi_option rsyslog_options[] = {
+	{"rsyslog-packet-size", required_argument, 0, "set maximum packet size for syslog messages (default 1024) WARNING! using packets > 1024 breaks RFC 3164 (#4.1)", uwsgi_opt_set_int, &u_rsyslog.packet_size, 0},
+	{"rsyslog-split-messages", no_argument, 0, "split big messages into multiple chunks if they are bigger than allowed packet size (default is false)", uwsgi_opt_true, &u_rsyslog.split_msg, 0},
+	{0, 0, 0, 0, 0, 0, 0},
+};
+
 
 ssize_t uwsgi_rsyslog_logger(struct uwsgi_logger *ul, char *message, size_t len) {
 
-	char buf[MAX_SYSLOG_PKT];
 	char ctime_storage[26];
 	time_t current_time;
 	int portn = 514;
@@ -48,6 +60,11 @@ ssize_t uwsgi_rsyslog_logger(struct uwsgi_logger *ul, char *message, size_t len)
 		if (port) *port = ':';
 		if (comma) *comma = ',';
 
+		if (!u_rsyslog.packet_size) u_rsyslog.packet_size = 1024;
+		if (!u_rsyslog.msg_size) u_rsyslog.msg_size = u_rsyslog.packet_size - 30;
+
+		ul->buf = uwsgi_malloc(uwsgi.log_master_bufsize);
+
                 ul->configured = 1;
         }
 
@@ -61,11 +78,21 @@ ssize_t uwsgi_rsyslog_logger(struct uwsgi_logger *ul, char *message, size_t len)
 #else
 	ctime_r(&current_time, ctime_storage);
 #endif
- 	rlen = snprintf(buf, MAX_SYSLOG_PKT, "<29>%.*s %s: %.*s", 15, ctime_storage+4, (char *) ul->data, (int) len, message);
-	if (rlen > 0) {
-		return sendto(ul->fd, buf, rlen, 0, (const struct sockaddr *) &ul->addr, ul->addr_len);
+
+	int pos, msg_len, ret;
+	for (pos=0 ; pos < (int) len ;) {
+		if (pos > 0 && !u_rsyslog.split_msg) return pos;
+		msg_len = ( ((int)len)-pos > u_rsyslog.msg_size ? u_rsyslog.msg_size : ((int)len)-pos);
+		rlen = snprintf(ul->buf, u_rsyslog.packet_size, "<29>%.*s %s: %.*s", 15, ctime_storage+4, (char *) ul->data, msg_len, &message[pos]);
+		if (rlen > 0 && rlen <= u_rsyslog.packet_size) {
+			ret = sendto(ul->fd, ul->buf, rlen, 0, (const struct sockaddr *) &ul->addr, ul->addr_len);
+			if (ret <= 0) return ret;
+			pos += msg_len;
+		} else {
+			return -1;
+		}
 	}
-	return -1;
+	return pos;
 
 }
 
@@ -77,6 +104,7 @@ struct uwsgi_plugin rsyslog_plugin = {
 
         .name = "rsyslog",
         .on_load = uwsgi_rsyslog_register,
+        .options = rsyslog_options,
 
 };
 

uwsgi.h

@@ -511,6 +511,7 @@ struct uwsgi_logger {
 	socklen_t addr_len;
 	int count;
 	struct msghdr msg;
+	char *buf;
 	// used by choosen logger
 	char *arg;
 	struct uwsgi_logger *next;