X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;ds=sidebyside;f=GHC%2FIO.hs;h=b3d590a02d455ee733c4f861f154a7da50a30590;hb=4c98224cdf6e5a1620721faea837656f429f4f27;hp=110ae688aea7197c89f75f40c0b56d58fdebc682;hpb=7de50399a42ee49b0473b7b6eea2b44a2f941a12;p=ghc-base.git

diff --git a/GHC/IO.hs b/GHC/IO.hs
index 110ae68..b3d590a 100644
--- a/GHC/IO.hs
+++ b/GHC/IO.hs
@@ -1,18 +1,30 @@
-{-# OPTIONS -fno-implicit-prelude -#include "HsCore.h" #-}
+{-# OPTIONS -fno-implicit-prelude -#include "HsBase.h" #-}
 
 #undef DEBUG_DUMP
 
--- -----------------------------------------------------------------------------
--- $Id: IO.hs,v 1.3 2002/02/05 17:32:26 simonmar Exp $
+-----------------------------------------------------------------------------
+-- |
+-- Module      :  GHC.IO
+-- Copyright   :  (c) The University of Glasgow, 1992-2001
+-- License     :  see libraries/base/LICENSE
+-- 
+-- Maintainer  :  libraries@haskell.org
+-- Stability   :  internal
+-- Portability :  non-portable
 --
--- (c) The University of Glasgow, 1992-2001
+-- String I\/O functions
 --
+-----------------------------------------------------------------------------
 
 module GHC.IO ( 
    hWaitForInput, hGetChar, hGetLine, hGetContents, hPutChar, hPutStr,
    commitBuffer',	-- hack, see below
    hGetcBuffered,	-- needed by ghc/compiler/utils/StringBuffer.lhs
-   hGetBuf, hPutBuf, slurpFile
+   hGetBuf, hPutBuf, slurpFile,
+   memcpy_ba_baoff,
+   memcpy_ptr_baoff,
+   memcpy_baoff_ba,
+   memcpy_baoff_ptr,
  ) where
 
 import Foreign
@@ -156,10 +168,13 @@ hGetLineBufferedLoop handle_ ref
 #endif
 
   xs <- unpack raw r off
+
+  -- if eol == True, then off is the offset of the '\n'
+  -- otherwise off == w and the buffer is now empty.
   if eol
-	then do if w == off + 1
-		   then writeIORef ref buf{ bufRPtr=0, bufWPtr=0 }
-		   else writeIORef ref buf{ bufRPtr = off + 1 }
+	then do if (w == off + 1)
+	    		then writeIORef ref buf{ bufRPtr=0, bufWPtr=0 }
+		   	else writeIORef ref buf{ bufRPtr = off + 1 }
 	        return (concat (reverse (xs:xss)))
 	else do
 	     maybe_buf <- maybeFillReadBuffer (haFD handle_) True (haIsStream handle_)
@@ -167,10 +182,12 @@ hGetLineBufferedLoop handle_ ref
 	     case maybe_buf of
 		-- Nothing indicates we caught an EOF, and we may have a
 		-- partial line to return.
-		Nothing -> let str = concat (reverse (xs:xss)) in
-		     	   if not (null str)
-			      then return str
-			      else ioe_EOF
+		Nothing -> do
+		     writeIORef ref buf{ bufRPtr=0, bufWPtr=0 }
+		     let str = concat (reverse (xs:xss))
+		     if not (null str)
+		        then return str
+		        else ioe_EOF
 		Just new_buf -> 
 		     hGetLineBufferedLoop handle_ ref new_buf (xs:xss)
 
@@ -304,7 +321,7 @@ lazyReadHaveBuffer h handle_ fd ref buf = do
 
 
 unpackAcc :: RawBuffer -> Int -> Int -> [Char] -> IO [Char]
-unpackAcc buf r 0 acc  = return ""
+unpackAcc buf r 0 acc  = return acc
 unpackAcc buf (I# r) (I# len) acc = IO $ \s -> unpack acc (len -# 1#) s
    where
     unpack acc i s
@@ -595,7 +612,8 @@ hPutBuf :: Handle			-- handle to write to
 	-> Int				-- number of bytes of data in buffer
 	-> IO ()
 hPutBuf handle ptr count
-  | count <= 0 = illegalBufferSize handle "hPutBuf" count
+  | count == 0 = return ()
+  | count <  0 = illegalBufferSize handle "hPutBuf" count
   | otherwise = 
     wantWritableHandle "hPutBuf" handle $ 
       \ handle_@Handle__{ haFD=fd, haBuffer=ref, haIsStream=is_stream } -> do
@@ -635,7 +653,8 @@ writeChunk fd ptr bytes = loop 0 bytes
 
 hGetBuf :: Handle -> Ptr a -> Int -> IO Int
 hGetBuf handle ptr count
-  | count <= 0 = illegalBufferSize handle "hGetBuf" count
+  | count == 0 = return 0
+  | count <  0 = illegalBufferSize handle "hGetBuf" count
   | otherwise = 
       wantReadableHandle "hGetBuf" handle $ 
 	\ handle_@Handle__{ haFD=fd, haBuffer=ref } -> do
@@ -682,6 +701,7 @@ slurpFile fname = do
     ioError (userError "slurpFile: file too big")
    else do
     let sz_i = fromIntegral sz
+    if sz_i == 0 then return (nullPtr, 0) else do
     chunk <- mallocBytes sz_i
     r <- hGetBuf handle chunk sz_i
     hClose handle