From 806fd19ecba0d58bf238a7b6f78e080da03eb9c7 Mon Sep 17 00:00:00 2001
From: Pieter Wuille <pieter.wuille@gmail.com>
Date: Sat, 21 Jun 2014 17:00:38 +0200
Subject: [PATCH] Allocate receive buffers in on the fly

---
 src/net.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/net.cpp b/src/net.cpp
index 757a06aae..707f58f8a 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -678,7 +678,6 @@ int CNetMessage::readHeader(const char *pch, unsigned int nBytes)
 
     // switch state to reading message data
     in_data = true;
-    vRecv.resize(hdr.nMessageSize);
 
     return nCopy;
 }
@@ -688,6 +687,11 @@ int CNetMessage::readData(const char *pch, unsigned int nBytes)
     unsigned int nRemaining = hdr.nMessageSize - nDataPos;
     unsigned int nCopy = std::min(nRemaining, nBytes);
 
+    if (vRecv.size() < nDataPos + nCopy) {
+        // Allocate up to 256 KiB ahead, but never more than the total message size.
+        vRecv.resize(std::min(hdr.nMessageSize, nDataPos + nCopy + 256 * 1024));
+    }
+
     memcpy(&vRecv[nDataPos], pch, nCopy);
     nDataPos += nCopy;