Dmitry Timoshkov : user32: WM_GETTEXT message converters have to 0-terminate output buffer if there is enough space even if there is no text to convert .

[Alexandre Julliard]

Module: wine
Branch: master
Commit: b9eb76dea0fe37cc0f0a4ca7f236b47d7fc98700
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=b9eb76dea0fe37cc0f0a4ca7f2...

Author: Dmitry Timoshkov <dmitry(a)codeweavers.com>
Date:   Thu Mar 22 19:08:21 2007 +0800

user32: WM_GETTEXT message converters have to 0-terminate output buffer if there is enough space even if there is no text to convert.

---

 dlls/user32/winproc.c |   15 ++++++++++-----
 1 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/dlls/user32/winproc.c b/dlls/user32/winproc.c
index 1d093a9..5a00e51 100644
--- a/dlls/user32/winproc.c
+++ b/dlls/user32/winproc.c
@@ -856,9 +856,11 @@ LRESULT WINPROC_CallProcAtoW( winproc_callback_t callback, HWND hwnd, UINT msg,
 
             if (!(ptr = get_buffer( buffer, sizeof(buffer), len ))) break;
             ret = callback( hwnd, msg, wParam, (LPARAM)ptr, result, arg );
-            if (*result && wParam)
+            if (wParam)
             {
-                RtlUnicodeToMultiByteN( str, wParam - 1, &len, ptr, strlenW(ptr) * sizeof(WCHAR) );
+                len = 0;
+                if (*result)
+                    RtlUnicodeToMultiByteN( str, wParam - 1, &len, ptr, strlenW(ptr) * sizeof(WCHAR) );
                 str[len] = 0;
                 *result = len;
             }
@@ -1091,10 +1093,13 @@ static LRESULT WINPROC_CallProcWtoA( winproc_callback_t callback, HWND hwnd, UIN
 
             if (!(ptr = get_buffer( buffer, sizeof(buffer), len ))) break;
             ret = callback( hwnd, msg, wParam, (LPARAM)ptr, result, arg );
-            if (*result && len)
+            if (len)
             {
-                RtlMultiByteToUnicodeN( (LPWSTR)lParam, wParam*sizeof(WCHAR), &len, ptr, strlen(ptr)+1 );
-                *result = len/sizeof(WCHAR) - 1;  /* do not count terminating null */
+                if (*result)
+                {
+                    RtlMultiByteToUnicodeN( (LPWSTR)lParam, wParam*sizeof(WCHAR), &len, ptr, strlen(ptr)+1 );
+                    *result = len/sizeof(WCHAR) - 1;  /* do not count terminating null */
+                }
                 ((LPWSTR)lParam)[*result] = 0;
             }
             free_buffer( buffer, ptr );