debian/: Imported the files from Sebastian's Debian package, part 2.

[collectd.git] / debian / examples / myplugin.c

diff --git a/debian/examples/myplugin.c b/debian/examples/myplugin.c
new file mode 100644 (file)
index 0000000..1bd8e42
--- /dev/null
+++ b/debian/examples/myplugin.c
@@ -0,0 +1,107 @@
+/*
+ * /usr/share/doc/collectd/examples/sample_plugin.c
+ *
+ * A sample plugin for collectd.
+ *
+ * Written by Sebastian Harl <sh@tokkee.org>
+ *
+ * This is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free 
+ * Software Foundation; either version 2 of the License, or (at your 
+ * option) any later version.
+ */
+
+#include <collectd/common.h>    /* rrd_update_file */
+#include <collectd/plugin.h>    /* plugin_* */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/* Optional config file support */
+/* #include <collectd/configfile.h> */
+
+/* Optional debugging support 
+ * (only available if collectd was compiled with debugging support) */
+/* #include <collectd/utils_debug.h> */
+
+#define MODULE_NAME "myplugin"
+
+/* Name of the rrd file under DataDir (/var/lib/collectd by default)
+ *
+ * The name may contain slashes to create subdirectories. */
+static char *my_rrd = "myplugin.rrd";
+
+/* DS definitions for the rrd file
+ *
+ * See the rrdcreate(1) manpage for details. The heartbeat is configurable in
+ * collectd. It defaults to 25. */
+static char *ds_def[] =
+{
+    "DS:my_ds:GAUGE:25:0:U",
+    NULL
+};
+
+/* DS count */
+static int ds_num = 1;
+
+/* Time at which the read function is called */
+extern time_t curtime;
+
+/* Initialize the plugin
+ *
+ * This function is called to set up a plugin before using it. */
+static void my_init(void)
+{
+    /* we have nothing to do here :-) */
+    return;
+}
+
+/* Get the data
+ *
+ * This function implements the magic used to get the desired values that
+ * should be stored in the rrd file. It uses plugin_submit to transfer the
+ * data to whatever place is configured in the config file. If there are more
+ * than one instances you should pass a uniq identifier as seconds argument to
+ * the plugin_submit function. */
+#define BUFSIZE 256
+static void my_read(void)
+{
+    long int data = 0;
+    char buf[BUFSIZE] = "";
+
+    /* magic ;-) */
+    data = random();
+
+    if (snprintf(buf, BUFSIZE, "%u:%li", 
+                (unsigned int)curtime, data) >= BUFSIZE)
+        return;
+
+    plugin_submit(MODULE_NAME, NULL, buf);
+    return;
+}
+#undef BUFSIZE
+
+/* Save the data
+ *
+ * This function saves the data to the appropriate location by calling
+ * rrd_update_file. It is used to "calculate" the filename and DS definition
+ * appropriate for the given instance. */
+static void my_write(host, inst, val)
+    char *host;
+    char *inst;
+    char *val;
+{
+    rrd_update_file(host, my_rrd, val, ds_def, ds_num);
+    return;
+}
+
+/* Register the plugin
+ *
+ * This function registers the plugin with collectd. It has to be named
+ * "module_register". */
+void module_register(void)
+{
+    plugin_register(MODULE_NAME, my_init, my_read, my_write);
+    return;
+}
+