From 1d9b36a1d9801131be7874fb0c9821332cf2ac57 Mon Sep 17 00:00:00 2001
From: Sebastian Harl <sh@tokkee.org>
Date: Sat, 16 Aug 2014 18:14:06 +0200
Subject: [PATCH] plugin: Added sdb_plugin_fetch_timeseries().

This function fetches a time-series from a named backend data-store using a
previously registered "time-series fetcher" callback.
---
 src/core/plugin.c         | 28 ++++++++++++++++++++++++++++
 src/include/core/plugin.h | 16 ++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/src/core/plugin.c b/src/core/plugin.c
index 85dd76f..d4bf1bd 100644
--- a/src/core/plugin.c
+++ b/src/core/plugin.c
@@ -1210,5 +1210,33 @@ sdb_plugin_logf(int prio, const char *fmt, ...)
 	return ret;
 } /* sdb_plugin_logf */
 
+sdb_timeseries_t *
+sdb_plugin_fetch_timeseries(const char *type, const char *id,
+		sdb_timeseries_opts_t *opts)
+{
+	sdb_plugin_cb_t *plugin;
+	sdb_plugin_fetch_ts_cb callback;
+	sdb_timeseries_t *ts;
+
+	ctx_t *old_ctx;
+
+	if ((! type) || (! id) || (! opts))
+		return NULL;
+
+	plugin = SDB_PLUGIN_CB(sdb_llist_search_by_name(ts_fetcher_list, type));
+	if (! plugin) {
+		sdb_log(SDB_LOG_ERR, "core: Cannot fetch time-series of type %s: "
+				"no such plugin loaded");
+		errno = ENOENT;
+		return NULL;
+	}
+
+	old_ctx = ctx_set(plugin->cb_ctx);
+	callback = (sdb_plugin_fetch_ts_cb)plugin->cb_callback;
+	ts = callback(id, opts, plugin->cb_user_data);
+	ctx_set(old_ctx);
+	return ts;
+} /* sdb_plugin_fetch_timeseries */
+
 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 
diff --git a/src/include/core/plugin.h b/src/include/core/plugin.h
index 4ccc983..0dce877 100644
--- a/src/include/core/plugin.h
+++ b/src/include/core/plugin.h
@@ -377,6 +377,22 @@ sdb_plugin_vlogf(int prio, const char *fmt, va_list ap);
 int
 sdb_plugin_logf(int prio, const char *fmt, ...);
 
+/*
+ * sdb_plugin_fetch_timeseries:
+ * Fetch the time-series identified by 'id' from a backend data-store of the
+ * specified 'type'. The type has to match an existing time-series fetcher
+ * callback's name. The identifier is passed through to the callback which
+ * then needs to make sense of it. The time-series option specify which data
+ * to fetch.
+ *
+ * Returns:
+ *  - a time-series on success
+ *  - NULL else
+ */
+sdb_timeseries_t *
+sdb_plugin_fetch_timeseries(const char *type, const char *id,
+		sdb_timeseries_opts_t *opts);
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif
-- 
2.30.2