From 3da36d67b99b4bcfd124c5c1d0877307ce7d8c24 Mon Sep 17 00:00:00 2001
From: Florian Forster <octo@collectd.org>
Date: Sat, 23 Mar 2013 09:27:24 +0100
Subject: [PATCH] tail_csv plugin: Implement the "TimeFrom" option.

---
 src/collectd.conf.in  |  1 +
 src/collectd.conf.pod | 12 +++++++++---
 src/tail_csv.c        | 33 +++++++++++++++++++++++++--------
 3 files changed, 35 insertions(+), 11 deletions(-)

diff --git a/src/collectd.conf.in b/src/collectd.conf.in
index 75e2291b..4d491c81 100644
--- a/src/collectd.conf.in
+++ b/src/collectd.conf.in
@@ -980,6 +980,7 @@
 #       Instance "snort-eth0"
 #       Interval 600
 #       Collect "dropped" "mbps" "alerts" "kpps"
+#       TimeFrom 0
 #   </File>
 #</Plugin>
 
diff --git a/src/collectd.conf.pod b/src/collectd.conf.pod
index c740808a..25717de2 100644
--- a/src/collectd.conf.pod
+++ b/src/collectd.conf.pod
@@ -5172,9 +5172,9 @@ created value lists. Otherwise, no type instance is used.
 
 =item B<ValueFrom> I<Index>
 
-Each line in the statistics file is broken into many fields with the first
-field, the timestamp of the line, is index with zero. This option configures to
-read the value from the field with index I<Index>.
+Configure to read the value from the field with the zero-based index I<Index>.
+If the value is parsed as signed integer, unsigned integer or double depends on
+the B<Type> setting, see above.
 
 =back
 
@@ -5200,6 +5200,12 @@ metric to be extracted from this statistic file.
 Configures the interval in which to read values from this instance / file.
 Defaults to the plugin's default interval.
 
+=item B<TimeFrom> I<Index>
+
+Rather than using the local time when dispatching a value, read the timestamp
+from the field with the zero-based index I<Index>. The value is interpreted as
+seconds since epoch. The value is parsed as a double and may be factional.
+
 =back
 
 =back
diff --git a/src/tail_csv.c b/src/tail_csv.c
index 3a8304a6..a70b6658 100644
--- a/src/tail_csv.c
+++ b/src/tail_csv.c
@@ -49,6 +49,7 @@ struct instance_definition_s {
     metric_definition_t **metric_list;
     size_t metric_list_len;
     cdtime_t interval;
+    int time_from;
     struct instance_definition_s *next;
 };
 typedef struct instance_definition_s instance_definition_t;
@@ -105,10 +106,12 @@ static int tcsv_read_metric (instance_definition_t *id,
     if (md->data_source_type == -1)
         return (EINVAL);
 
-    if (md->value_from >= fields_num)
+    if ((md->value_from >= fields_num) || (id->time_from >= fields_num))
         return (EINVAL);
 
-    t = parse_time (fields[0]);
+    t = 0;
+    if (id->time_from >= 0)
+        t = parse_time (fields[id->time_from]);
 
     status = parse_value (fields[md->value_from], &v, md->data_source_type);
     if (status != 0)
@@ -117,6 +120,19 @@ static int tcsv_read_metric (instance_definition_t *id,
     return (tcsv_submit (id, md, v, t));
 }
 
+static _Bool tcsv_check_index (int index, size_t fields_num, char const *name)
+{
+    if (index < 0)
+        return 1;
+    else if (((size_t) index) < fields_num)
+        return 1;
+
+    ERROR ("tail_csv plugin: Metric \"%s\": Request for index %i when "
+            "only %zu fields are available.",
+            name, index, fields_num);
+    return (0);
+}
+
 static int tcsv_read_buffer (instance_definition_t *id,
         char *buffer, size_t buffer_size)
 {
@@ -178,12 +194,9 @@ static int tcsv_read_buffer (instance_definition_t *id,
     for (i = 0; i < id->metric_list_len; ++i){
         metric_definition_t *md = id->metric_list[i];
 
-        if (((size_t) md->value_from) >= metrics_num) {
-            ERROR ("tail_csv plugin: Metric \"%s\": Request for index %i when "
-                    "only %zu fields are available.",
-                    md->name, md->value_from, metrics_num);
+        if (!tcsv_check_index (md->value_from, metrics_num, md->name)
+                || !tcsv_check_index (id->time_from, metrics_num, md->name))
             continue;
-        }
 
         tcsv_read_metric (id, md, metrics, metrics_num);
     }
@@ -351,7 +364,8 @@ static void tcsv_instance_definition_destroy(void *arg){
     if (id == NULL)
         return;
 
-    cu_tail_destroy (id->tail);
+    if (id->tail != NULL)
+        cu_tail_destroy (id->tail);
     id->tail = NULL;
 
     sfree(id->instance);
@@ -416,6 +430,7 @@ static int tcsv_config_add_file(oconfig_item_t *ci)
     id->instance = NULL;
     id->path = NULL;
     id->metric_list = NULL;
+    id->time_from = -1;
     id->next = NULL;
 
     status = cf_util_get_string (ci, &id->path);
@@ -437,6 +452,8 @@ static int tcsv_config_add_file(oconfig_item_t *ci)
             status = tcsv_config_add_instance_collect(id, option);
         else if (strcasecmp("Interval", option->key) == 0)
             cf_util_get_cdtime(option, &id->interval);
+        else if (strcasecmp("TimeFrom", option->key) == 0)
+            status = tcsv_config_get_index (option, &id->time_from);
         else {
             WARNING("tail_csv plugin: Option `%s' not allowed here.", option->key);
             status = -1;
-- 
2.30.2