src/common/byte-tag-list.cc
changeset 4502 07d34c0d8d18
parent 3762 622a33a8820c
child 6397 a1608a9a11f3
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/common/byte-tag-list.cc	Wed Jun 03 08:49:40 2009 +0200
@@ -0,0 +1,421 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2008 INRIA
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
+ */
+#include "byte-tag-list.h"
+#include "ns3/log.h"
+#include <vector>
+#include <string.h>
+
+NS_LOG_COMPONENT_DEFINE ("ByteTagList");
+
+#define USE_FREE_LIST 1
+#define FREE_LIST_SIZE 1000
+#define OFFSET_MAX (2147483647)
+
+namespace ns3 {
+
+struct ByteTagListData {
+  uint32_t size;
+  uint32_t count;
+  uint32_t dirty;
+  uint8_t data[4];
+};
+
+#ifdef USE_FREE_LIST
+static class ByteTagListDataFreeList : public std::vector<struct ByteTagListData *>
+{
+public:
+  ~ByteTagListDataFreeList ();
+} g_freeList;
+static uint32_t g_maxSize = 0;
+
+ByteTagListDataFreeList::~ByteTagListDataFreeList ()
+{
+  for (ByteTagListDataFreeList::iterator i = begin ();
+       i != end (); i++)
+    {
+      uint8_t *buffer = (uint8_t *)(*i);
+      delete [] buffer;
+    }
+}
+#endif /* USE_FREE_LIST */
+
+ByteTagList::Iterator::Item::Item (TagBuffer buf_)
+    : buf (buf_)
+{}
+
+bool 
+ByteTagList::Iterator::HasNext (void) const
+{
+  return m_current < m_end;
+}
+struct ByteTagList::Iterator::Item 
+ByteTagList::Iterator::Next (void)
+{
+  NS_ASSERT (HasNext ());
+  struct Item item = Item (TagBuffer (m_current+16, m_end));
+  item.tid.SetUid (m_nextTid);
+  item.size = m_nextSize;
+  item.start = std::max (m_nextStart, m_offsetStart);
+  item.end = std::min (m_nextEnd, m_offsetEnd);
+  m_current += 4 + 4 + 4 + 4 + item.size;
+  item.buf.TrimAtEnd (m_end - m_current);
+  PrepareForNext ();
+  return item;
+}
+void
+ByteTagList::Iterator::PrepareForNext (void)
+{
+  while (m_current < m_end)
+    {
+      TagBuffer buf = TagBuffer (m_current, m_end);
+      m_nextTid = buf.ReadU32 ();
+      m_nextSize = buf.ReadU32 ();
+      m_nextStart = buf.ReadU32 ();
+      m_nextEnd = buf.ReadU32 ();
+      if (m_nextStart >= m_offsetEnd || m_nextEnd <= m_offsetStart)
+	{
+	  m_current += 4 + 4 + 4 + 4 + m_nextSize;
+	}
+      else
+	{
+	  break;
+	}
+    }
+}
+ByteTagList::Iterator::Iterator (uint8_t *start, uint8_t *end, int32_t offsetStart, int32_t offsetEnd)
+  : m_current (start),
+    m_end (end),
+    m_offsetStart (offsetStart),
+    m_offsetEnd (offsetEnd)
+{
+  PrepareForNext ();
+}
+
+uint32_t 
+ByteTagList::Iterator::GetOffsetStart (void) const
+{
+  return m_offsetStart;
+}
+
+
+ByteTagList::ByteTagList ()
+  : m_used (0),
+    m_data (0)
+{
+  NS_LOG_FUNCTION (this);
+}
+ByteTagList::ByteTagList (const ByteTagList &o)
+  : m_used (o.m_used),
+    m_data (o.m_data)
+{
+  NS_LOG_FUNCTION (this << &o);
+  if (m_data != 0)
+    {
+      m_data->count++;
+    }
+}
+ByteTagList &
+ByteTagList::operator = (const ByteTagList &o)
+{
+  NS_LOG_FUNCTION (this << &o);
+  if (this == &o)
+    {
+      return *this;
+    }
+
+  Deallocate (m_data);
+  m_data = o.m_data;
+  m_used = o.m_used;
+  if (m_data != 0)
+    {
+      m_data->count++;
+    }
+  return *this;
+}
+ByteTagList::~ByteTagList ()
+{
+  NS_LOG_FUNCTION (this);
+  Deallocate (m_data);
+  m_data = 0;
+  m_used = 0;
+}
+
+TagBuffer
+ByteTagList::Add (TypeId tid, uint32_t bufferSize, int32_t start, int32_t end)
+{
+  NS_LOG_FUNCTION (this << tid << bufferSize << start << end);
+  uint32_t spaceNeeded = m_used + bufferSize + 4 + 4 + 4 + 4;
+  NS_ASSERT (m_used <= spaceNeeded);
+  if (m_data == 0)
+    {
+      m_data = Allocate (spaceNeeded);
+      m_used = 0;
+    } 
+  else if (m_data->size < spaceNeeded ||
+	   (m_data->count != 1 && m_data->dirty != m_used))
+    {
+      struct ByteTagListData *newData = Allocate (spaceNeeded);
+      memcpy (&newData->data, &m_data->data, m_used);
+      Deallocate (m_data);
+      m_data = newData;
+    }
+  TagBuffer tag = TagBuffer (&m_data->data[m_used], 
+			     &m_data->data[spaceNeeded]);
+  tag.WriteU32 (tid.GetUid ());
+  tag.WriteU32 (bufferSize);
+  tag.WriteU32 (start);
+  tag.WriteU32 (end);
+  m_used = spaceNeeded;
+  m_data->dirty = m_used;
+  return tag;
+}
+
+void 
+ByteTagList::Add (const ByteTagList &o)
+{
+  NS_LOG_FUNCTION (this << &o);
+  ByteTagList::Iterator i = o.BeginAll ();
+  while (i.HasNext ())
+    {
+      ByteTagList::Iterator::Item item = i.Next ();
+      TagBuffer buf = Add (item.tid, item.size, item.start, item.end);
+      buf.CopyFrom (item.buf);
+    }
+}
+
+void 
+ByteTagList::RemoveAll (void)
+{
+  NS_LOG_FUNCTION (this);
+  Deallocate (m_data);
+  m_data = 0;
+  m_used = 0;
+}
+
+ByteTagList::Iterator 
+ByteTagList::BeginAll (void) const
+{
+  NS_LOG_FUNCTION (this);
+  // I am not totally sure but I might need to use 
+  // INT32_MIN instead of zero below.
+  return Begin (0, OFFSET_MAX);
+}
+
+ByteTagList::Iterator 
+ByteTagList::Begin (int32_t offsetStart, int32_t offsetEnd) const
+{
+  NS_LOG_FUNCTION (this << offsetStart << offsetEnd);
+  if (m_data == 0)
+    {
+      return Iterator (0, 0, offsetStart, offsetEnd);
+    }
+  else
+    {
+      return Iterator (m_data->data, &m_data->data[m_used], offsetStart, offsetEnd);
+    }
+}
+
+bool 
+ByteTagList::IsDirtyAtEnd (int32_t appendOffset)
+{
+  NS_LOG_FUNCTION (this << appendOffset);
+  ByteTagList::Iterator i = BeginAll ();
+  while (i.HasNext ())
+    {
+      ByteTagList::Iterator::Item item = i.Next ();
+      if (item.end > appendOffset)
+	{
+	  return true;
+	}
+    }
+  return false;
+}
+
+bool 
+ByteTagList::IsDirtyAtStart (int32_t prependOffset)
+{
+  NS_LOG_FUNCTION (this << prependOffset);
+  ByteTagList::Iterator i = BeginAll ();
+  while (i.HasNext ())
+    {
+      ByteTagList::Iterator::Item item = i.Next ();
+      if (item.start < prependOffset)
+	{
+	  return true;
+	}
+    }
+  return false;
+}
+
+void 
+ByteTagList::AddAtEnd (int32_t adjustment, int32_t appendOffset)
+{
+  NS_LOG_FUNCTION (this << adjustment << appendOffset);
+  if (adjustment == 0 && !IsDirtyAtEnd (appendOffset))
+    {
+      return;
+    }
+  ByteTagList list;
+  ByteTagList::Iterator i = BeginAll ();
+  while (i.HasNext ())
+    {
+      ByteTagList::Iterator::Item item = i.Next ();
+      item.start += adjustment;
+      item.end += adjustment;
+
+      if (item.start >= appendOffset)
+	{
+	  continue;
+	}
+      else if (item.start < appendOffset && item.end > appendOffset)
+	{
+	  item.end = appendOffset;
+	}
+      else
+	{
+	  // nothing to do.
+	}
+      TagBuffer buf = list.Add (item.tid, item.size, item.start, item.end);
+      buf.CopyFrom (item.buf);
+    }
+  *this = list;  
+}
+
+void 
+ByteTagList::AddAtStart (int32_t adjustment, int32_t prependOffset)
+{
+  NS_LOG_FUNCTION (this << adjustment << prependOffset);
+  if (adjustment == 0 && !IsDirtyAtStart (prependOffset))
+    {
+      return;
+    }
+  ByteTagList list;
+  ByteTagList::Iterator i = BeginAll ();
+  while (i.HasNext ())
+    {
+      ByteTagList::Iterator::Item item = i.Next ();
+      item.start += adjustment;
+      item.end += adjustment;
+
+      if (item.end <= prependOffset)
+	{
+	  continue;
+	}
+      else if (item.end > prependOffset && item.start < prependOffset)
+	{
+	  item.start = prependOffset;
+	}
+      else
+	{
+	  // nothing to do.
+	}
+      TagBuffer buf = list.Add (item.tid, item.size, item.start, item.end);
+      buf.CopyFrom (item.buf);
+    }
+  *this = list;
+}
+
+#ifdef USE_FREE_LIST
+
+struct ByteTagListData *
+ByteTagList::Allocate (uint32_t size)
+{
+  NS_LOG_FUNCTION (this << size);
+  while (!g_freeList.empty ())
+    {
+      struct ByteTagListData *data = g_freeList.back ();
+      g_freeList.pop_back ();
+      NS_ASSERT (data != 0);
+      if (data->size >= size)
+	{
+	  data->count = 1;
+	  data->dirty = 0;
+	  return data;
+	}
+      uint8_t *buffer = (uint8_t *)data;
+      delete [] buffer;
+    }
+  uint8_t *buffer = new uint8_t [std::max (size, g_maxSize) + sizeof (struct ByteTagListData) - 4];
+  struct ByteTagListData *data = (struct ByteTagListData *)buffer;
+  data->count = 1;
+  data->size = size;
+  data->dirty = 0;
+  return data;
+}
+
+void 
+ByteTagList::Deallocate (struct ByteTagListData *data)
+{
+  NS_LOG_FUNCTION (this << data);
+  if (data == 0)
+    {
+      return;
+    }
+  g_maxSize = std::max (g_maxSize, data->size);
+  data->count--;
+  if (data->count == 0)
+    {
+      if (g_freeList.size () > FREE_LIST_SIZE ||
+	  data->size < g_maxSize)
+	{
+	  uint8_t *buffer = (uint8_t *)data;
+	  delete [] buffer;
+	}
+      else
+	{
+	  g_freeList.push_back (data);
+	}
+    }
+}
+
+#else /* USE_FREE_LIST */
+
+struct ByteTagListData *
+ByteTagList::Allocate (uint32_t size)
+{
+  NS_LOG_FUNCTION (this << size);
+  uint8_t *buffer = new uint8_t [size + sizeof (struct ByteTagListData) - 4];
+  struct ByteTagListData *data = (struct ByteTagListData *)buffer;
+  data->count = 1;
+  data->size = size;
+  data->dirty = 0;
+  return data;
+}
+
+void 
+ByteTagList::Deallocate (struct ByteTagListData *data)
+{
+  NS_LOG_FUNCTION (this << data);
+  if (data == 0)
+    {
+      return;
+    }
+  data->count--;
+  if (data->count == 0)
+    {
+      uint8_t *buffer = (uint8_t *)data;
+      delete [] buffer;
+    }
+}
+
+#endif /* USE_FREE_LIST */
+
+
+} // namespace ns3