[commit: base] master: BufferedIO: fix bug in writeBufNonBlocking introduced by commit 7d39e100 (040313e)

[Joey Adams]

Repository : ssh://darcs.haskell.org//srv/darcs/packages/base

On branch  : master

http://hackage.haskell.org/trac/ghc/changeset/040313eb7d79aca47cb897479c6bca1af5e2ffb3

>---------------------------------------------------------------

commit 040313eb7d79aca47cb897479c6bca1af5e2ffb3
Author: Joey Adams <joeyadams3.14159 at gmail.com>
Date:   Mon Dec 24 12:44:22 2012 -0500

    BufferedIO: fix bug in writeBufNonBlocking introduced by commit 7d39e100
    
    bufferAdjustL does nothing but update bufL, and set bufL = bufR = 0
    when bufL == bufR.  It ignores the old bufL.
    
    writeBufNonBlocking is currently unused.  It is only used to implement
    flushWriteBuffer0, which is never called by base
    (hPutBufNonBlocking uses a blocking flush).

>---------------------------------------------------------------

 GHC/IO/BufferedIO.hs |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/GHC/IO/BufferedIO.hs b/GHC/IO/BufferedIO.hs
index ef78d90..b715c61 100644
--- a/GHC/IO/BufferedIO.hs
+++ b/GHC/IO/BufferedIO.hs
@@ -123,5 +123,5 @@ writeBufNonBlocking dev bbuf = do
   let bytes = bufferElems bbuf
   res <- withBuffer bbuf $ \ptr ->
             IODevice.writeNonBlocking dev (ptr `plusPtr` bufL bbuf) bytes
-  return (res, bufferAdjustL res bbuf)
+  return (res, bufferAdjustL (bufL bbuf + res) bbuf)