From d4bd658d84f06dd021e629d5e226f2ca195bafa7 Mon Sep 17 00:00:00 2001
From: Unbit <info@unbit.it>
Date: Mon, 21 Oct 2013 19:01:06 +0200
Subject: [PATCH] added restorable metrics

---
 core/metrics.c | 13 +++++++++++--
 core/uwsgi.c   |  5 ++++-
 uwsgi.h        |  1 +
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/core/metrics.c b/core/metrics.c
index d4215b78..ec9faa56 100644
--- a/core/metrics.c
+++ b/core/metrics.c
@@ -385,13 +385,13 @@ static void *uwsgi_metrics_loop(void *arg) {
 			// gather the new value based on the type of collection strategy
 			switch(metric->collect_way) {
 				case UWSGI_METRIC_PTR:
-					*metric->value = *metric->ptr;
+					*metric->value = metric->initial_value + *metric->ptr;
 					break;
 				// aliases are NOOP
 				case UWSGI_METRIC_ALIAS:
 					break;
 				case UWSGI_METRIC_SUM:
-					*metric->value = uwsgi_metric_sum(metric);
+					*metric->value = metric->initial_value + uwsgi_metric_sum(metric);
 					break;
 				case UWSGI_METRIC_FILE:
 					uwsgi_log("reading from file\n");
@@ -736,5 +736,14 @@ void uwsgi_setup_metrics() {
 
 	if (uwsgi.metrics_dir) {
 		uwsgi_log("memory allocated for metrics storage: %llu bytes (%llu MB)\n", uwsgi.metrics_cnt * uwsgi.page_size, (uwsgi.metrics_cnt * uwsgi.page_size)/1024/1024);
+		if (uwsgi.metrics_dir_restore) {
+			metric = uwsgi.metrics;
+        		while(metric) {
+				if (metric->map) {
+					metric->initial_value = strtoll(metric->map, NULL, 10);
+				}
+				metric = metric->next;
+			}
+		}
 	}
 }
diff --git a/core/uwsgi.c b/core/uwsgi.c
index b1f5c4d8..222adbd4 100644
--- a/core/uwsgi.c
+++ b/core/uwsgi.c
@@ -511,8 +511,11 @@ static struct uwsgi_option uwsgi_base_options[] = {
 	{"exception-handler", required_argument, 0, "add an exception handler", uwsgi_opt_add_string_list, &uwsgi.exception_handlers_instance, UWSGI_OPT_MASTER},
 
 	{"enable-metrics", no_argument, 0, "enable metrics subsystem", uwsgi_opt_true, &uwsgi.has_metrics, UWSGI_OPT_MASTER},
-	{"metrics-dir", required_argument, 0, "exports metrics as text files in the specified directory", uwsgi_opt_set_str, &uwsgi.metrics_dir, UWSGI_OPT_METRICS|UWSGI_OPT_MASTER},
 	{"metric", required_argument, 0, "add a custom metric", uwsgi_opt_add_string_list, &uwsgi.additional_metrics, UWSGI_OPT_METRICS|UWSGI_OPT_MASTER},
+	{"metrics-dir", required_argument, 0, "exports metrics as text files in the specified directory", uwsgi_opt_set_str, &uwsgi.metrics_dir, UWSGI_OPT_METRICS|UWSGI_OPT_MASTER},
+	{"metrics-dir-restore", no_argument, 0, "restore last value taken from the metrics dir", uwsgi_opt_true, &uwsgi.metrics_dir_restore, UWSGI_OPT_METRICS|UWSGI_OPT_MASTER},
+	{"metric-dir", required_argument, 0, "exports metrics as text files in the specified directory", uwsgi_opt_set_str, &uwsgi.metrics_dir, UWSGI_OPT_METRICS|UWSGI_OPT_MASTER},
+	{"metric-dir-restore", no_argument, 0, "restore last value taken from the metrics dir", uwsgi_opt_true, &uwsgi.metrics_dir_restore, UWSGI_OPT_METRICS|UWSGI_OPT_MASTER},
 
 	{"udp", required_argument, 0, "run the udp server on the specified address", uwsgi_opt_set_str, &uwsgi.udp_socket, UWSGI_OPT_MASTER},
 	{"stats", required_argument, 0, "enable the stats server on the specified address", uwsgi_opt_set_str, &uwsgi.stats, UWSGI_OPT_MASTER},
diff --git a/uwsgi.h b/uwsgi.h
index ed17cccb..0b1b28ad 100644
--- a/uwsgi.h
+++ b/uwsgi.h
@@ -2574,6 +2574,7 @@ struct uwsgi_server {
 	struct uwsgi_metric *metrics;
 	int has_metrics;
 	char *metrics_dir;
+	int metrics_dir_restore;
 	uint64_t metrics_cnt;
 	struct uwsgi_string_list *additional_metrics;