[core] reset connection counters per connection

reset connection counters per connection, not per request

adjust mod_accesslog and mod_rrdtool usage

continue to count mod_rrdtool per request rather than per connection
so that data is updated after each request, rather than aggregated
to the end of a potentially long-lived connection with many keep-alives.

src/connections.c

@@ -228,6 +228,8 @@ static void connection_fdwaitqueue_append(connection *con) {
     connection_list_append(&con->srv->fdwaitqueue, con);
 }
 
+static void request_reset (request_st * const r);
+
 static void connection_handle_response_end_state(request_st * const r, connection * const con) {
 	/* call request_done hook if http_status set (e.g. to log request) */
 	/* (even if error, connection dropped, as long as http_status is set) */
@@ -242,7 +244,11 @@ static void connection_handle_response_end_state(request_st * const r, connectio
 	}
 
         if (r->keep_alive) {
-		connection_reset(con);
+		request_reset(r);
+		con->is_readable = 1; /* potentially trigger optimistic read */
+		/*(accounting used by mod_accesslog for HTTP/1.0 and HTTP/1.1)*/
+		r->bytes_read_ckpt = con->bytes_read;
+		r->bytes_written_ckpt = con->bytes_written;
 #if 0
 		r->start_ts = con->read_idle_ts = log_epoch_secs;
 #endif
@@ -764,6 +770,8 @@ request_reset (request_st * const r) {
 static void connection_reset(connection *con) {
 	request_st * const r = &con->request;
 	request_reset(r);
+	r->bytes_read_ckpt = 0;
+	r->bytes_written_ckpt = 0;
 	con->is_readable = 1;
 
 	con->bytes_written = 0;
@@ -875,7 +883,7 @@ static int connection_handle_read_state(connection * const con)  {
     int pipelined_request_start = 0;
     unsigned short hoff[8192]; /* max num header lines + 3; 16k on stack */
 
-    if (con->request_count > 1 && 0 == con->bytes_read) {
+    if (con->request_count > 1 && con->bytes_read == r->bytes_read_ckpt) {
         keepalive_request_start = 1;
         if (NULL != c) { /* !chunkqueue_is_empty(cq)) */
             pipelined_request_start = 1;
@@ -931,7 +939,7 @@ static int connection_handle_read_state(connection * const con)  {
     } while ((c = connection_read_header_more(con, cq, c, clen)));
 
     if (keepalive_request_start) {
-        if (0 != con->bytes_read) {
+        if (con->bytes_read > r->bytes_read_ckpt) {
             /* update r->start_ts timestamp when first byte of
              * next request is received on a keep-alive connection */
             r->start_ts = log_epoch_secs;

src/mod_accesslog.c

@@ -981,13 +981,16 @@ static int log_access_record (const request_st * const r, buffer * const b, form
 				break;
 
 			case FORMAT_BYTES_OUT_NO_HEADER:
-				if (con->bytes_written > 0) {
-					off_t bytes = con->bytes_written - (off_t)r->resp_header_len;
+			{
+				off_t bytes = con->bytes_written - r->bytes_written_ckpt;
+				if (bytes > 0) {
+					bytes -= (off_t)r->resp_header_len;
 					buffer_append_int(b, bytes > 0 ? bytes : 0);
 				} else {
 					buffer_append_string_len(b, CONST_STR_LEN("-"));
 				}
 				break;
+			}
 			case FORMAT_HEADER:
 				if (NULL != (vb = http_header_request_get(r, HTTP_HEADER_UNSPECIFIED, CONST_BUF_LEN(&f->string)))) {
 					accesslog_append_escaped(b, vb);
@@ -1018,19 +1021,25 @@ static int log_access_record (const request_st * const r, buffer * const b, form
 				}
 				break;
 			case FORMAT_BYTES_OUT:
-				if (con->bytes_written > 0) {
-					buffer_append_int(b, con->bytes_written);
+			{
+				off_t bytes = con->bytes_written - r->bytes_written_ckpt;
+				if (bytes > 0) {
+					buffer_append_int(b, bytes);
 				} else {
 					buffer_append_string_len(b, CONST_STR_LEN("-"));
 				}
 				break;
+			}
 			case FORMAT_BYTES_IN:
-				if (con->bytes_read > 0) {
-					buffer_append_int(b, con->bytes_read);
+			{
+				off_t bytes = con->bytes_read - r->bytes_read_ckpt;
+				if (bytes > 0) {
+					buffer_append_int(b, bytes);
 				} else {
 					buffer_append_string_len(b, CONST_STR_LEN("-"));
 				}
 				break;
+			}
 			case FORMAT_SERVER_NAME:
 				if (!buffer_string_is_empty(r->server_name)) {
 					buffer_append_string_buffer(b, r->server_name);

src/mod_rrdtool.c

@@ -424,8 +424,8 @@ REQUESTDONE_FUNC(mod_rrd_account) {
     rrd_config * const rrd = p->conf.rrd;
     if (NULL == rrd) return HANDLER_GO_ON;
     ++rrd->requests;
-    rrd->bytes_written += r->con->bytes_written;
-    rrd->bytes_read    += r->con->bytes_read;
+        rrd->bytes_written += (r->con->bytes_written - r->bytes_written_ckpt);
+        rrd->bytes_read    += (r->con->bytes_read    - r->bytes_read_ckpt);
 
     return HANDLER_GO_ON;
 }

src/request.h

@@ -178,6 +178,8 @@ struct request_st {
     buffer *tmp_buf;                    /* shared; same as srv->tmp_buf */
     response_dechunk *gw_dechunk;
 
+    off_t bytes_written_ckpt; /* used by mod_accesslog */
+    off_t bytes_read_ckpt;    /* used by mod_accesslog */
     struct timespec start_hp;
     time_t start_ts;