From: Sree Harsha Totakura <totakura@in.tum.de>
Date: Mon, 27 Feb 2012 11:10:56 +0000 (+0000)
Subject: -added prepare_buffer_for_read
X-Git-Tag: initial-import-from-subversion-38251~14617
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=a48e053620c5081570710ff072fd857ba73b0f8d;p=oweals%2Fgnunet.git

-added prepare_buffer_for_read
---

diff --git a/src/stream/stream_api.c b/src/stream/stream_api.c
index 6ae3dbefe..2ccf4e892 100644
--- a/src/stream/stream_api.c
+++ b/src/stream/stream_api.c
@@ -663,6 +663,128 @@ write_data (struct GNUNET_STREAM_Socket *socket)
 }
 
 
+/**
+ * Task for calling the read processor
+ *
+ * @param cls the socket
+ * @param tc the task context
+ */
+static void
+call_read_processor_task (void *cls,
+                          const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+  struct GNUNET_STREAM_Socket *socket = cls;
+  size_t read_size;
+  size_t valid_read_size;
+
+  if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN) return;
+
+  GNUNET_assert (NULL != socket->read_handle);
+  GNUNET_assert (NULL != socket->read_handle->proc);
+  GNUNET_assert (NULL != socket->copy_buffer);
+  GNUNET_assert (0 != socket->copy_buffer_size);
+
+  valid_read_size = socket->copy_buffer_size - socket->copy_buffer_read_offset;
+  GNUNET_assert (0 != valid_read_size);
+
+  read_size = socket->read_handle->proc (socket->read_handle->proc_cls,
+                                         socket->status,
+                                         socket->copy_buffer 
+                                         + socket->copy_buffer_read_offset,
+                                         valid_read_size);
+
+  GNUNET_assert (read_size <= valid_read_size);
+  socket->copy_buffer_read_offset += read_size;
+
+  /* Free the copy buffer once it has been read entirely */
+  if (socket->copy_buffer_read_offset == socket->copy_buffer_size)
+    {
+      GNUNET_free (socket->copy_buffer);
+      socket->copy_buffer = NULL;
+      socket->copy_buffer_size = 0;
+      socket->copy_buffer_read_offset = 0;
+    }
+
+  /* Free the read handle */
+  GNUNET_free (socket->read_handle);
+  socket->read_handle = NULL;
+}
+
+
+/**
+ * Prepares the receive buffer for possible reads; Should only be called when
+ * there is a valid READ io request pending and socket->copy_buffer is empty
+ *
+ * @param socket the socket pointer
+ */
+static void 
+prepare_buffer_for_read (struct GNUNET_STREAM_Socket *socket)
+{
+  unsigned int packet;
+  uint32_t offset_increase;
+  uint32_t sequence_increase;
+
+  GNUNET_assert (NULL == socket->copy_buffer);
+  GNUNET_assert (NULL != socket->read_handle);
+
+  /* Check the bitmap for any holes */
+  for (packet=0; packet < GNUNET_STREAM_ACK_BITMAP_BIT_LENGTH; packet++)
+    {
+      if (GNUNET_NO == ackbitmap_is_bit_set (&socket->ack_bitmap,
+                                             packet))
+        break;
+    }
+
+  sequence_increase = packet;
+
+  if (0 == sequence_increase)              /* The first packet is still missing */
+    {
+      return;
+    }
+  
+  /* Copy data to copy buffer */
+  GNUNET_assert (0 < socket->receive_buffer_boundaries[sequence_increase-1]);
+  socket->copy_buffer = 
+    GNUNET_malloc (socket->receive_buffer_boundaries[sequence_increase-1]);
+  memcpy (socket->copy_buffer, 
+          socket->receive_buffer,
+          socket->receive_buffer_boundaries[sequence_increase-1]);
+  
+  /* Shift the data in the receive buffer */
+  memmove (socket->receive_buffer,
+           socket->receive_buffer 
+           + socket->receive_buffer_boundaries[sequence_increase-1],
+           socket->receive_buffer_size - socket->receive_buffer_boundaries[sequence_increase-1]);
+  
+  /* Shift the bitmap */
+  socket->ack_bitmap = socket->ack_bitmap >> sequence_increase;
+  
+  /* Set read_sequence_number */
+  socket->read_sequence_number += sequence_increase;
+  
+  /* Set read_offset */
+  offset_increase = socket->receive_buffer_boundaries[sequence_increase-1];
+  socket->read_offset += offset_increase;
+  
+  /* Fix relative boundaries */
+  for (packet=0; packet < GNUNET_STREAM_ACK_BITMAP_BIT_LENGTH; packet++)
+    {
+      if (packet < GNUNET_STREAM_ACK_BITMAP_BIT_LENGTH - sequence_increase)
+        {
+          socket->receive_buffer_boundaries[packet] = 
+            socket->receive_buffer_boundaries[packet + sequence_increase] 
+            - offset_increase;
+        }
+      else
+        socket->receive_buffer_boundaries[packet] = 0;
+    }
+
+  GNUNET_SCHEDULER_add_continuation (&call_read_processor_task,
+                                     socket,
+                                     GNUNET_SCHEDULER_REASON_PREREQ_DONE);
+}
+
+
 /**
  * Handler for DATA messages; Same for both client and server
  *
@@ -757,6 +879,12 @@ handle_data (struct GNUNET_STREAM_Socket *socket,
                                          &ack_task,
                                          socket);
        }
+
+      if ((NULL != socket->read_handle) /* A read handle is waiting */
+          && (NULL == socket->copy_buffer)) /* And the copy buffer is empty */
+        {
+          prepare_buffer_for_read (socket);
+        }
       
       break;
 
@@ -1653,53 +1781,6 @@ mesh_peer_disconnect_callback (void *cls,
 }
 
 
-/**
- * Task for calling the read processor
- *
- * @param cls the socket
- */
-static void
-call_read_processor_task (void *cls,
-                          const struct GNUNET_SCHEDULER_TaskContext *tc)
-{
-  struct GNUNET_STREAM_Socket *socket = cls;
-  size_t read_size;
-  size_t valid_read_size;
-
-  if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN) return;
-
-  GNUNET_assert (NULL != socket->read_handle);
-  GNUNET_assert (NULL != socket->read_handle->proc);
-  GNUNET_assert (NULL != socket->copy_buffer);
-  GNUNET_assert (0 != socket->copy_buffer_size);
-
-  valid_read_size = socket->copy_buffer_size - socket->copy_buffer_read_offset;
-  GNUNET_assert (0 != valid_read_size);
-
-  read_size = socket->read_handle->proc (socket->read_handle->proc_cls,
-                                         socket->status,
-                                         socket->copy_buffer 
-                                         + socket->copy_buffer_read_offset,
-                                         valid_read_size);
-
-  GNUNET_assert (read_size <= valid_read_size);
-  socket->copy_buffer_read_offset += read_size;
-
-  /* Free the copy buffer once it has been read entirely */
-  if (socket->copy_buffer_read_offset == socket->copy_buffer_size)
-    {
-      GNUNET_free (socket->copy_buffer);
-      socket->copy_buffer = NULL;
-      socket->copy_buffer_size = 0;
-      socket->copy_buffer_read_offset = 0;
-    }
-
-  /* Free the read handle */
-  GNUNET_free (socket->read_handle);
-  socket->read_handle = NULL;
-}
-
-
 /*****************/
 /* API functions */
 /*****************/
@@ -2054,10 +2135,7 @@ GNUNET_STREAM_read (struct GNUNET_STREAM_Socket *socket,
 		    GNUNET_STREAM_DataProcessor proc,
 		    void *proc_cls)
 {
-  unsigned int packet;
   struct GNUNET_STREAM_IOReadHandle *read_handle;
-  uint32_t offset_increase;
-  uint32_t sequence_increase;
   
   /* Return NULL if there is already a read handle; the user has to cancel that
   first before continuing or has to wait until it is completed */
@@ -2069,61 +2147,11 @@ GNUNET_STREAM_read (struct GNUNET_STREAM_Socket *socket,
 
   /* if previous copy buffer is still not read call the data processor on it */
   if (NULL != socket->copy_buffer)
-    {
-      GNUNET_SCHEDULER_add_now (&call_read_processor_task,
-                                socket);
-    }
-
-  /* Check the bitmap for any holes */
-  for (packet=0; packet < GNUNET_STREAM_ACK_BITMAP_BIT_LENGTH; packet++)
-    {
-      if (GNUNET_NO == ackbitmap_is_bit_set (&socket->ack_bitmap,
-                                             packet))
-        break;
-    }
-
-  sequence_increase = packet;
-
-  if (0 == sequence_increase)              /* The first packet is still missing */
-    {
-      /* We can't do anything until it arrives */
-    }
+    GNUNET_SCHEDULER_add_continuation (&call_read_processor_task,
+                                       socket,
+                                       GNUNET_SCHEDULER_REASON_PREREQ_DONE);
   else
-    {
-      /* Copy data to copy buffer */
-      GNUNET_assert (0 < socket->receive_buffer_boundaries[sequence_increase-1]);
-      socket->copy_buffer = 
-        GNUNET_malloc (socket->receive_buffer_boundaries[sequence_increase-1]);
-
-      /* Shift the data in the receive buffer */
-      memmove (socket->receive_buffer,
-               socket->receive_buffer 
-               + socket->receive_buffer_boundaries[sequence_increase-1],
-               socket->receive_buffer_size - socket->receive_buffer_boundaries[sequence_increase-1]);
-      
-      /* Shift the bitmap */
-      socket->ack_bitmap = socket->ack_bitmap >> sequence_increase;
-
-      /* Set read_sequence_number */
-      socket->read_sequence_number += sequence_increase;
-
-      /* Set read_offset */
-      offset_increase = socket->receive_buffer_boundaries[sequence_increase-1];
-      socket->read_offset += offset_increase;
-      
-      /* Fix relative boundaries */
-      for (packet=0; packet < GNUNET_STREAM_ACK_BITMAP_BIT_LENGTH; packet++)
-        {
-          if (packet < GNUNET_STREAM_ACK_BITMAP_BIT_LENGTH - sequence_increase)
-            {
-              socket->receive_buffer_boundaries[packet] = 
-                socket->receive_buffer_boundaries[packet + sequence_increase] 
-                - offset_increase;
-            }
-          else
-            socket->receive_buffer_boundaries[packet] = 0;
-        }
-    }
+    prepare_buffer_for_read (socket);
 
   return read_handle;
 }