From 028fda02376c5d127d210c1e652472e44c572422 Mon Sep 17 00:00:00 2001
From: Vinnie Falco <vinnie.falco@gmail.com>
Date: Wed, 2 Aug 2017 19:36:31 -0700
Subject: [PATCH] Fix stream::read_size_hint calculation

---
 CHANGELOG.md                                  | 1 +
 include/boost/beast/websocket/impl/stream.ipp | 7 +++++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 16a4dc4f..2fc69f61 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@ WebSocket:
 * Refactor fail/clode code
 * Call do_fail from read_some
 * eof on accept returns error::closed
+* Fix stream::read_size_hint calculation
 
 --------------------------------------------------------------------------------
 
diff --git a/include/boost/beast/websocket/impl/stream.ipp b/include/boost/beast/websocket/impl/stream.ipp
index 3c119d9b..cc84d9fa 100644
--- a/include/boost/beast/websocket/impl/stream.ipp
+++ b/include/boost/beast/websocket/impl/stream.ipp
@@ -98,8 +98,11 @@ read_size_hint(
                 buffer.max_size(), clamp(rd_.remain));
         }
     }
-    return (std::min)(buffer.max_size(), (std::max)(
-        (std::max)(+tcp_frame_size, clamp(rd_.remain)),
+    return (std::min)(
+        buffer.max_size() - buffer.size(),
+        (std::max)((std::max)(
+            +tcp_frame_size,
+            clamp(rd_.remain)),
             buffer.capacity() - buffer.size()));
 }