[GNUnet-SVN] r10113 - gnunet/src/util

[gnunet]

Author: grothoff
Date: 2010-01-22 15:20:31 +0100 (Fri, 22 Jan 2010)
New Revision: 10113

Modified:
   gnunet/src/util/server_nc.c
Log:
finishing nc implementation

Modified: gnunet/src/util/server_nc.c
===================================================================
--- gnunet/src/util/server_nc.c 2010-01-21 21:03:45 UTC (rev 10112)
+++ gnunet/src/util/server_nc.c 2010-01-22 14:20:31 UTC (rev 10113)
@@ -50,12 +50,16 @@
 
   struct ClientList *next;
 
+  struct GNUNET_SERVER_NotificationContext *nc;
+
   struct GNUNET_SERVER_Client *client;
 
   struct GNUNET_CONNECTION_TransmitHandle *th;
 
-  struct PendingMessageList *pending;
+  struct PendingMessageList *pending_head;
 
+  struct PendingMessageList *pending_tail;
+
   unsigned int num_pending;
 
 };
@@ -105,9 +109,9 @@
     nc->clients = pos->next;
   else
     prev->next = pos->next;
-  while (NULL != (pml = pos->pending))
+  while (NULL != (pml = pos->pending_head))
     {
-      pos->pending = pml->next;
+      pos->pending_head = pml->next;
       GNUNET_free (pml);
     }
   GNUNET_free (pos);
@@ -155,9 +159,9 @@
       nc->clients = pos->next;
       GNUNET_SERVER_receive_done (pos->client, GNUNET_NO);
       GNUNET_SERVER_client_drop (pos->client); 
-      while (NULL != (pml = pos->pending))
+      while (NULL != (pml = pos->pending_head))
        {
-         pos->pending = pml->next;
+         pos->pending_head = pml->next;
          GNUNET_free (pml);
        }
       GNUNET_free (pos);
@@ -179,10 +183,114 @@
 GNUNET_SERVER_notification_context_add (struct 
GNUNET_SERVER_NotificationContext *nc,
                                        struct GNUNET_SERVER_Client *client)
 {
+  struct ClientList *cl;
+
+  cl = GNUNET_malloc (sizeof (struct ClientList));
+  cl->next = nc->clients;
+  cl->nc = nc;
+  cl->client = client;
+  nc->clients = cl;
 }
 
 
 /**
+ * Function called to notify a client about the socket begin ready to
+ * queue more data.  "buf" will be NULL and "size" zero if the socket
+ * was closed for writing in the meantime.
+ *
+ * @param cls the 'struct ClientList *'
+ * @param size number of bytes available in buf
+ * @param buf where the callee should write the message
+ * @return number of bytes written to buf
+ */
+static size_t
+transmit_message (void *cls,
+                 size_t size,
+                 void *buf)
+{
+  struct ClientList *cl = cls;
+  char *cbuf = buf;
+  struct PendingMessageList *pml;
+  uint16_t msize;
+  size_t ret;
+
+  cl->th = NULL;
+  if (buf == NULL)
+    {
+      /* 'cl' should be freed via disconnect notification shortly */
+      return 0;
+    }
+  ret = 0;
+  while (cl->pending_head != NULL)
+    {
+      pml = cl->pending_head;
+      cl->pending_head = pml->next;
+      if (pml->next == NULL)
+       cl->pending_tail = NULL;
+      msize = ntohs (pml->msg->size);
+      if (size < msize)
+       break;
+      memcpy (&cbuf[ret], pml->msg, msize);
+      ret += msize;
+      size -= msize;
+      GNUNET_free (pml);
+    }
+  if (cl->pending_head != NULL)    
+    cl->th = GNUNET_SERVER_notify_transmit_ready (cl->client,
+                                                 ntohs 
(cl->pending_head->msg->size),
+                                                 GNUNET_TIME_UNIT_FOREVER_REL,
+                                                 &transmit_message,
+                                                 cl);
+  return ret;
+}
+
+
+/**
+ * Send a message to a particular client.
+ *
+ * @param nc context to modify
+ * @param client client to transmit to
+ * @param msg message to send
+ * @param can_drop can this message be dropped due to queue length limitations
+ */
+static void
+do_unicast (struct GNUNET_SERVER_NotificationContext *nc,
+           struct ClientList *client,
+           const struct GNUNET_MessageHeader *msg,
+           int can_drop)
+{
+  struct PendingMessageList *pml;
+  uint16_t size;
+
+  if ( (client->num_pending > nc->queue_length) &&
+       (GNUNET_YES == can_drop) )
+    return; /* drop! */
+  if (client->num_pending > nc->queue_length)
+    {
+      /* FIXME: consider checking for other messages in the
+        queue that are 'droppable' */
+    }
+  size = ntohs (msg->size);
+  pml = GNUNET_malloc (sizeof (struct PendingMessageList) + size);
+  pml->msg = (const struct GNUNET_MessageHeader*) &pml[1];
+  pml->can_drop = can_drop;
+  memcpy (&pml[1], msg, size);
+  /* append */
+  if (client->pending_tail != NULL)
+    client->pending_tail->next = pml;
+  else
+    client->pending_head = pml;
+  client->pending_tail = pml;
+  if (client->th == NULL)
+    client->th = GNUNET_SERVER_notify_transmit_ready (client->client,
+                                                     ntohs 
(client->pending_head->msg->size),
+                                                     
GNUNET_TIME_UNIT_FOREVER_REL,
+                                                     &transmit_message,
+                                                     client);
+} 
+
+
+/**
  * Send a message to a particular client; must have
  * already been added to the notification context.
  *
@@ -197,6 +305,17 @@
                                            const struct GNUNET_MessageHeader 
*msg,
                                            int can_drop)
 {
+  struct ClientList *pos;
+  
+  pos = nc->clients;
+  while (NULL != pos)
+    {
+      if (pos->client == client)
+       break;
+      pos = pos->next;
+    }
+  GNUNET_assert (pos != NULL);
+  do_unicast (nc, pos, msg, can_drop); 
 }
 
 
@@ -212,6 +331,14 @@
                                              const struct GNUNET_MessageHeader 
*msg,
                                              int can_drop)
 {
+  struct ClientList *pos;
+  
+  pos = nc->clients;
+  while (NULL != pos)
+    {
+      do_unicast (nc, pos, msg, can_drop);
+      pos = pos->next;
+    }
 }