rrdtool plugin: Assure that values, that are older then the newest value in the cache...

Otherwise there might be gaps in the graphs.

diff --git a/src/rrdtool.c b/src/rrdtool.c
index 52557c0..ea96290 100644 (file)
--- a/src/rrdtool.c
+++ b/src/rrdtool.c
@@ -36,6 +36,7 @@ struct rrd_cache_s
        int    values_num;
        char **values;
        time_t first_value;
+       time_t last_value;
 };
 typedef struct rrd_cache_s rrd_cache_t;
 
@@ -434,7 +435,7 @@ static int value_list_to_filename (char *buffer, int buffer_len,
 } /* int value_list_to_filename */
 
 static rrd_cache_t *rrd_cache_insert (const char *filename,
-               const char *value)
+               const char *value, time_t value_time)
 {
        rrd_cache_t *rc = NULL;
        int new_rc = 0;
@@ -450,9 +451,18 @@ static rrd_cache_t *rrd_cache_insert (const char *filename,
                rc->values_num = 0;
                rc->values = NULL;
                rc->first_value = 0;
+               rc->last_value = 0;
                new_rc = 1;
        }
 
+       if (rc->last_value >= value_time)
+       {
+               WARNING ("rrdtool plugin: (rc->last_value = %u) >= (value_time = %u)",
+                               (unsigned int) rc->last_value,
+                               (unsigned int) value_time);
+               return (NULL);
+       }
+
        rc->values = (char **) realloc ((void *) rc->values,
                        (rc->values_num + 1) * sizeof (char *));
        if (rc->values == NULL)
@@ -475,7 +485,8 @@ static rrd_cache_t *rrd_cache_insert (const char *filename,
                rc->values_num++;
 
        if (rc->values_num == 1)
-               rc->first_value = time (NULL);
+               rc->first_value = value_time;
+       rc->last_value = value_time;
 
        /* Insert if this is the first value */
        if ((cache != NULL) && (new_rc == 1))
@@ -496,7 +507,8 @@ static rrd_cache_t *rrd_cache_insert (const char *filename,
                avl_insert (cache, cache_key, rc);
        }
 
-       DEBUG ("rrd_cache_insert (%s, %s) = %p", filename, value, (void *) rc);
+       DEBUG ("rrd_cache_insert (%s, %s, %u) = %p", filename, value,
+                       (unsigned int) value_time, (void *) rc);
 
        return (rc);
 } /* rrd_cache_t *rrd_cache_insert */
@@ -658,7 +670,7 @@ static int rrd_write (const data_set_t *ds, const value_list_t *vl)
        }
 
        pthread_mutex_lock (&cache_lock);
-       rc = rrd_cache_insert (filename, values);
+       rc = rrd_cache_insert (filename, values, vl->time);
        if (rc == NULL)
        {
                pthread_mutex_unlock (&cache_lock);