From 4811680d2a4416cd20795f9284c067d703042de2 Mon Sep 17 00:00:00 2001
From: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
Date: Mon, 1 Feb 2010 08:28:11 +0100
Subject: [PATCH] avoid copying bytes one after the other.

---
 src/common/buffer.cc | 32 ++++++++++++++++++++++++++++++++
 src/common/buffer.h  |  2 ++
 src/common/packet.cc |  9 +--------
 3 files changed, 35 insertions(+), 8 deletions(-)

diff --git a/src/common/buffer.cc b/src/common/buffer.cc
index 7f1ee2f5f..cc1f107d3 100644
--- a/src/common/buffer.cc
+++ b/src/common/buffer.cc
@@ -726,6 +726,38 @@ Buffer::CopyData(std::ostream *os, uint32_t size) const
     }
 }
 
+uint32_t 
+Buffer::CopyData (uint8_t *buffer, uint32_t size) const
+{
+  uint32_t originalSize = size;
+  if (size > 0)
+    {
+      uint32_t tmpsize = std::min (m_zeroAreaStart-m_start, size);
+      memcpy (buffer, (const char*)(m_data->m_data + m_start), tmpsize);
+      buffer += tmpsize;
+      if (size > tmpsize) 
+        { 
+          size -= m_zeroAreaStart-m_start;
+          tmpsize = std::min (m_zeroAreaEnd - m_zeroAreaStart, size);
+          uint32_t left = tmpsize;
+          while (left > 0)
+            {
+              uint32_t toWrite = std::min (left, g_zeroes.size);
+              memcpy (buffer, g_zeroes.buffer, toWrite);
+              left -= toWrite;
+              buffer += toWrite;
+            }
+          if (size > tmpsize)
+            {
+              size -= tmpsize;
+              tmpsize = std::min (m_end - m_zeroAreaEnd, size);
+              memcpy (buffer, (const char*)(m_data->m_data + m_zeroAreaStart), tmpsize);
+            }
+        }
+    }
+  return originalSize - size;
+}
+
 /******************************************************
  *            The buffer iterator below.
  ******************************************************/
diff --git a/src/common/buffer.h b/src/common/buffer.h
index 4d542251f..33d32b9d2 100644
--- a/src/common/buffer.h
+++ b/src/common/buffer.h
@@ -487,6 +487,8 @@ public:
    */
   void CopyData (std::ostream *os, uint32_t size) const;
 
+  uint32_t CopyData (uint8_t *buffer, uint32_t size) const;
+
   Buffer (Buffer const &o);
   Buffer &operator = (Buffer const &o);
   Buffer ();
diff --git a/src/common/packet.cc b/src/common/packet.cc
index 244c26e6f..8f48811a7 100644
--- a/src/common/packet.cc
+++ b/src/common/packet.cc
@@ -350,14 +350,7 @@ Packet::PeekData (void) const
 uint32_t 
 Packet::CopyData (uint8_t *buffer, uint32_t size) const
 {
-  Buffer::Iterator i = m_buffer.Begin ();
-  uint32_t cur = 0;
-  while (!i.IsEnd () && cur < size)
-    {
-      buffer[cur] = i.ReadU8 ();
-      cur++;
-    }
-  return cur;
+  return m_buffer.CopyData (buffer, size);
 }
 
 void