made _read() non-greedy - it now returns as soon as any amount of data has been read...

[reactos.git] / reactos / lib / msvcrt / io / read.c

diff --git a/reactos/lib/msvcrt/io/read.c b/reactos/lib/msvcrt/io/read.c
index 520e2ec..555a3db 100644 (file)
--- a/reactos/lib/msvcrt/io/read.c
+++ b/reactos/lib/msvcrt/io/read.c
@@ -1,22 +1,67 @@
 /*
  * COPYRIGHT:   See COPYING in the top level directory
  * PROJECT:     ReactOS system libraries
- * FILE:        lib/crtdll/io/read.c
+ * FILE:        lib/msvcrt/io/read.c
  * PURPOSE:     Reads a file
  * PROGRAMER:   Boudewijn Dekker
  * UPDATE HISTORY:
- *              28/12/98: Created
+ *              28/12/1998: Created
+ *              03/05/2002: made _read() non-greedy - it now returns as soon as
+ *                          any amount of data has been read. It's the expected
+ *                          behavior for line-buffered streams (KJK::Hyperion)
  */
-#include <crtdll/io.h>
 #include <windows.h>
+#include <msvcrt/io.h>
+#include <msvcrt/internal/file.h>
 
-size_t _read(int _fd, void *_buf, size_t _nbyte)
+#define NDEBUG
+#include <msvcrt/msvcrtdbg.h>
+
+size_t _read(int _fd, void *_buf, size_t _nbyte)
 {
-   size_t _rbyte;
-   
-   if (!ReadFile(_get_osfhandle(_fd),_buf,_nbyte,&_rbyte,NULL)) 
-     {
-       return -1;
-     }
+   DWORD _rbyte = 0, nbyte = _nbyte;
+   char *bufp = (char*)_buf;
+   HANDLE hfile;
+   int istext;
+
+   DPRINT("_read(fd %d, buf %x, nbyte %d)\n", _fd, _buf, _nbyte);
+
+   /* null read */
+   if(_nbyte == 0)
+      return 0;
+
+   hfile = _get_osfhandle(_fd);
+   istext = __fileno_getmode(_fd) & O_TEXT;
+
+   /* read data */
+   if (!ReadFile(hfile, bufp, nbyte, &_rbyte, NULL))
+   {
+      /* failure */
+      return -1;
+   }
+      
+   /* text mode */
+   if (_rbyte && istext)
+   {
+      int cr = 0;
+      DWORD count = _rbyte;
+
+      /* repeat for all bytes in the buffer */
+      for(; count; bufp++, count--)
+      {
+         /* carriage return */
+         if (*bufp == '\r')
+            cr++;
+         /* shift characters back, to ignore carriage returns */
+         else if (cr != 0)
+            *(bufp - cr) = *bufp;
+
+      }
+
+      /* ignore the carriage returns */
+      _rbyte -= cr;
+   }
+
+   DPRINT("%d\n", _rbyte);
    return _rbyte;
 }