-skeleton for monitor API

1 files changed, 162 insertions, 3 deletions

diff --git a/src/namestore/namestore_api_monitor.c b/src/namestore/namestore_api_monitor.c
index 4c242d17d..e2caea8a5 100644
--- a/src/namestore/namestore_api_monitor.c
+++ b/src/namestore/namestore_api_monitor.c
@@ -35,16 +35,149 @@
 #include "namestore.h"
 
 
-
 /**
  * Handle for a monitoring activity.
  */
 struct GNUNET_NAMESTORE_ZoneMonitor
 {
+  /**
+   * Configuration (to reconnect).
+   */
+  const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+  /**
+   * Handle to namestore service.
+   */
+  struct GNUNET_CLIENT_Connection *h;
+
+  /**
+   * Function to call on events.
+   */
+  GNUNET_NAMESTORE_RecordMonitor monitor;
+
+  /**
+   * Closure for 'monitor'.
+   */
+  void *monitor_cls;
+
+  /**
+   * Transmission handle to client.
+   */
+  struct GNUNET_CLIENT_TransmitHandle *th;
+
+  /**
+   * Monitored zone.
+   */
+  struct GNUNET_CRYPTO_ShortHashCode zone;
+
+  /**
+   * GNUNET_YES if we monitor all zones, GNUNET_NO if we only monitor 'zone'.
+   */
+  int all_zones;
 };
 
 
 /**
+ * Send our request to start monitoring to the service.
+ *
+ * @param cls the monitor handle
+ * @param size number of bytes available in buf
+ * @param buf where to copy the message to the service
+ * @return number of bytes copied to buf
+ */
+static size_t
+transmit_monitor_message (void *cls,
+                          size_t size,
+                          void *buf);
+
+
+/**
+ * Reconnect to the namestore service.
+ *
+ * @param zm monitor to reconnect
+ */
+static void
+reconnect (struct GNUNET_NAMESTORE_ZoneMonitor *zm)
+{
+  if (NULL != zm->h)
+    GNUNET_CLIENT_disconnect (zm->h);
+  zm->monitor (zm->monitor_cls,
+               NULL,
+               GNUNET_TIME_UNIT_ZERO_ABS,
+               NULL, 0, NULL, NULL);
+  GNUNET_assert (NULL != (zm->h = GNUNET_CLIENT_connect ("namestore", zm->cfg)));
+  zm->th = GNUNET_CLIENT_notify_transmit_ready (zm->h,
+                                                sizeof (struct ZoneMonitorStartMessage),
+                                                GNUNET_TIME_UNIT_FOREVER_REL,
+                                                GNUNET_YES,
+                                                &transmit_monitor_message,
+                                                zm);
+}
+
+
+/**
+ * We've received a notification about a change to our zone.
+ * Forward to monitor callback.
+ *
+ * @param cls the zone monitor handle
+ * @param msg the message from the service.
+ */
+static void
+handle_updates (void *cls,
+                const struct GNUNET_MessageHeader *msg)
+{
+  struct GNUNET_NAMESTORE_ZoneMonitor *zm = cls;
+
+  if (NULL == msg)
+  {
+    reconnect (zm);
+    return;
+  }
+  // FIXME: parse, validate
+
+  GNUNET_CLIENT_receive (zm->h,
+                         &handle_updates,
+                         zm,
+                         GNUNET_TIME_UNIT_FOREVER_REL);
+  // FIXME: call 'monitor'.
+  // zm->monitor (zm->monitor_cls, ...);
+}
+
+
+/**
+ * Send our request to start monitoring to the service.
+ *
+ * @param cls the monitor handle
+ * @param size number of bytes available in buf
+ * @param buf where to copy the message to the service
+ * @return number of bytes copied to buf
+ */
+static size_t
+transmit_monitor_message (void *cls,
+                          size_t size,
+                          void *buf)
+{
+  struct GNUNET_NAMESTORE_ZoneMonitor *zm = cls;
+  struct ZoneMonitorStartMessage sm;
+
+  if (size < sizeof (struct ZoneMonitorStartMessage))
+  {    
+    reconnect (zm);
+    return 0;
+  }
+ 
+  sm.zone = zm->zone;
+  sm.all_zones = htonl (zm->all_zones);
+  memcpy (buf, &sm, sizeof (sm));
+  GNUNET_CLIENT_receive (zm->h,
+                         &handle_updates,
+                         zm,
+                         GNUNET_TIME_UNIT_FOREVER_REL);
+  return sizeof (sm);
+}
+
+
+/**
  * Begin monitoring a zone for changes.  Will first call the 'monitor' function
  * on all existing records in the selected zone(s) and then call it whenever
  * a record changes.
@@ -61,8 +194,27 @@ GNUNET_NAMESTORE_zone_monitor_start (const struct GNUNET_CONFIGURATION_Handle *c
                                      GNUNET_NAMESTORE_RecordMonitor monitor,
                                      void *monitor_cls)
 {
-  GNUNET_break (0);
-  return NULL;
+  struct GNUNET_NAMESTORE_ZoneMonitor *zm;
+  struct GNUNET_CLIENT_Connection *client;
+
+  if (NULL == (client = GNUNET_CLIENT_connect ("namestore", cfg)))
+    return NULL; 
+  zm = GNUNET_new (struct GNUNET_NAMESTORE_ZoneMonitor);
+  zm->cfg = cfg;
+  zm->h = client;
+  if (NULL == zone)
+    zm->all_zones = GNUNET_YES;
+  else
+    zm->zone = *zone;
+  zm->monitor = monitor;
+  zm->monitor_cls = monitor_cls;
+  zm->th = GNUNET_CLIENT_notify_transmit_ready (zm->h,
+                                                sizeof (struct ZoneMonitorStartMessage),
+                                                GNUNET_TIME_UNIT_FOREVER_REL,
+                                                GNUNET_YES,
+                                                &transmit_monitor_message,
+                                                zm);
+  return zm;
 }
 
 
@@ -74,6 +226,13 @@ GNUNET_NAMESTORE_zone_monitor_start (const struct GNUNET_CONFIGURATION_Handle *c
 void
 GNUNET_NAMESTORE_zone_monitor_stop (struct GNUNET_NAMESTORE_ZoneMonitor *zm)
 {
+  if (NULL != zm->th)
+  {
+    GNUNET_CLIENT_notify_transmit_ready_cancel (zm->th);
+    zm->th = NULL;
+  }
+  GNUNET_CLIENT_disconnect (zm->h);
+  GNUNET_free (zm);
 }
 
 /* end of namestore_api_monitor.c */