[Patches] MBCS codes fails on zero length string.

[Mark Hammond]

Fixes the MBCS codec to work correctly with zero length strings.

Release info:

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Mark.

diff -c -r2.13 unicodeobject.c
*** unicodeobject.c	2000/05/01 21:27:20	2.13
--- unicodeobject.c	2000/05/03 06:53:20
***************
*** 1555,1561 ****

      /* First get the size of the result */
      DWORD usize = MultiByteToWideChar(CP_ACP, 0, s, size, NULL,
0);
!     if (usize==0)
          return PyErr_SetFromWindowsErrWithFilename(0, NULL);

      v = _PyUnicode_New(usize);
--- 1555,1561 ----

      /* First get the size of the result */
      DWORD usize = MultiByteToWideChar(CP_ACP, 0, s, size, NULL,
0);
!     if (size > 0 && usize==0)
          return PyErr_SetFromWindowsErrWithFilename(0, NULL);

      v = _PyUnicode_New(usize);
***************
*** 1578,1586 ****
  {
      PyObject *repr;
      char *s;

      /* First get the size of the result */
!     DWORD mbcssize = WideCharToMultiByte(CP_ACP, 0, p, size, NULL,
0, NULL, NULL);
      if (mbcssize==0)
          return PyErr_SetFromWindowsErrWithFilename(0, NULL);

--- 1578,1591 ----
  {
      PyObject *repr;
      char *s;
+     DWORD mbcssize;

+     /* If there are no characters, bail now! */
+     if (size==0)
+ 	    return PyString_FromString("");
+
      /* First get the size of the result */
!     mbcssize = WideCharToMultiByte(CP_ACP, 0, p, size, NULL, 0,
NULL, NULL);
      if (mbcssize==0)
          return PyErr_SetFromWindowsErrWithFilename(0, NULL);