plugin.[ch]: Added support for an optional plugin shutdown function.

A plugin may register a shutdown function using plugin_register_shutdown ().
This function is called when collectd terminates either during normal
termination or after SIGINT or SIGTERM have been received.

Signed-off-by: Sebastian Harl <sh@tokkee.org>

diff --git a/src/collectd.c b/src/collectd.c
index 64da576..a1e15bf 100644 (file)
--- a/src/collectd.c
+++ b/src/collectd.c
@@ -444,6 +444,8 @@ int main (int argc, char **argv)
 #endif
                start_client ();
 
+       plugin_shutdown_all ();
+
 #if COLLECT_DEBUG
        if (logfile != NULL)
                DBG_STOPFILE("debug file closed.");

diff --git a/src/plugin.c b/src/plugin.c
index 697449e..46a1c61 100644 (file)
--- a/src/plugin.c
+++ b/src/plugin.c
@@ -34,6 +34,7 @@ typedef struct plugin
        void (*init) (void);
        void (*read) (void);
        void (*write) (char *host, char *inst, char *val);
+       void (*shutdown) (void);
        struct plugin *next;
 } plugin_t;
 
@@ -286,6 +287,19 @@ void plugin_read_all (const int *loop)
 }
 
 /*
+ * Call `shutdown' on all plugins (if given)
+ */
+void plugin_shutdown_all (void)
+{
+       plugin_t *p;
+
+       for (p = first_plugin; NULL != p; p = p->next)
+               if (NULL != p->shutdown)
+                       (*p->shutdown) ();
+       return;
+}
+
+/*
  * Add plugin to the linked list of registered plugins.
  */
 void plugin_register (char *type,
@@ -317,11 +331,27 @@ void plugin_register (char *type,
        p->read  = read;
        p->write = write;
 
+       p->shutdown = NULL;
+
        p->next = first_plugin;
        first_plugin = p;
 }
 
 /*
+ * Register the shutdown function (optional).
+ */
+int plugin_register_shutdown (char *type, void (*shutdown) (void))
+{
+       plugin_t *p = plugin_search (type);
+
+       if (NULL == p)
+               return -1;
+
+       p->shutdown = shutdown;
+       return 0;
+}
+
+/*
  * Send received data back to the plugin/module which will append DS
  * definitions and pass it on to ``rrd_update_file''.
  */

diff --git a/src/plugin.h b/src/plugin.h
index a77c87f..45e9b49 100644 (file)
--- a/src/plugin.h
+++ b/src/plugin.h
@@ -101,11 +101,15 @@ int  plugin_load_all (char *dir);
 void plugin_init_all (void);
 void plugin_read_all (const int *loop);
 
+void plugin_shutdown_all (void);
+
 void plugin_register (char *type,
                void (*init) (void),
                void (*read) (void),
                void (*write) (char *, char *, char *));
 
+int plugin_register_shutdown (char *, void (*) (void));
+
 /*
  * NAME
  *  plugin_write