winiet/ftp.c question about a strncpy elimination

[Peter Berg Larsen]

What is the correct behaviour in FtpGetCurrentDirectory if the buffer
parameter is to small?

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/wininet/wininet/ftpgetcurrentdirectory.asp


Index: dlls/wininet/ftp.c
===================================================================
RCS file: /home/wine/wine/dlls/wininet/ftp.c,v
retrieving revision 1.53
diff -u -r1.53 ftp.c
--- dlls/wininet/ftp.c  28 Mar 2005 14:58:52 -0000      1.53
+++ dlls/wininet/ftp.c  15 Apr 2005 20:15:04 -0000
@@ -813,6 +813,13 @@
  *           FTP_FtpGetCurrentDirectoryA (Internal)
  *
  * Retrieves the current directory
+ *
+ * Parameters
+ *
+ * lpwfs                [I] Handle
+ * lpszCurrentDirectory [O] The absolute current path with '\0' termination.
+ * lpwdCurrentDirectory [I] The size of lpszCurrentDirectory.
+ *                      [O] The length of the absolute current path in lpszCurrentDirectory.
  *
  * RETURNS
  *    TRUE on success
@@ -864,11 +871,19 @@
             }

             len = lastpos - firstpos - 1;
-            strncpyW(lpszCurrentDirectory, &lpszResponseBuffer[firstpos+1],
-                len < *lpdwCurrentDirectory ? len : *lpdwCurrentDirectory);
-            HeapFree(GetProcessHeap(), 0, lpszResponseBuffer);
-            *lpdwCurrentDirectory = len;
-            bSuccess = TRUE;
+            if (len >= *lpdwCurrentDirectory)
+            {
+                *lpdwCurrentDirectory = len + 1;
+                FTP_SetResponseError(ERROR_INTERNET_BAD_OPTION_LENGTH);
+            }
+            else
+            {
+                *lpdwCurrentDirectory = len;
+                memcpy(lpszCurrentDirectory, &lpszResponseBuffer[firstpos+1], len*sizeof(WCHAR));
+                lpszCurrentDirectory[len] = '\0';
+                bSuccess = TRUE;
+           }
+           HeapFree(GetProcessHeap(), 0, lpszResponseBuffer);
         }
         else
             FTP_SetResponseError(nResCode);