[reactos] 03/03: [SHLWAPI] Fix a trivial bug in PathFileExistsDefExtW() that seems to exist since 16+ years in Wine.

[Hermès Bélusca-Maïto]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=3199fdbd4430542384d49…

commit 3199fdbd4430542384d49b32cf2dede02ff6bab4
Author:     Hermès Bélusca-Maïto <hermes.belusca-maito(a)reactos.org>
AuthorDate: Mon Jun 28 02:06:15 2021 +0200
Commit:     Hermès Bélusca-Maïto <hermes.belusca-maito(a)reactos.org>
CommitDate: Mon Jun 28 02:19:31 2021 +0200

    [SHLWAPI] Fix a trivial bug in PathFileExistsDefExtW() that seems to exist since 16+
years in Wine.
    
    Suppose dwFlags == 1 | 4 (i.e. skipping the flag 2).
    Then the while-loop would only run once, because at the second iteration
    (after dwWhich >>= 1; has been executed once), dwWhich value == 2, but
    dwWhich & 0x1 == 0, which makes the while-loop condition false.
    Instead the loop should run, but the handling of the extension should be
    skipped.
---
 dll/win32/shlwapi/path.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/dll/win32/shlwapi/path.c b/dll/win32/shlwapi/path.c
index f3149f35e58..fc698251cf2 100644
--- a/dll/win32/shlwapi/path.c
+++ b/dll/win32/shlwapi/path.c
@@ -40,7 +40,12 @@
 WINE_DEFAULT_DEBUG_CHANNEL(shell);
 
 #ifdef __REACTOS__
+
+#include <shlobj.h>
+#include <shlwapi_undoc.h>
+
 int WINAPI IsNetDrive(int drive);
+
 #else
 
 /* Get a function pointer from a DLL handle */
@@ -1127,17 +1132,32 @@ BOOL WINAPI PathFileExistsDefExtW(LPWSTR lpszPath,DWORD dwWhich)
   if (dwWhich)
   {
     LPCWSTR szExt = PathFindExtensionW(lpszPath);
+#ifndef __REACTOS__
     if (!*szExt || dwWhich & 0x40)
+#else
+    if (!*szExt || dwWhich & WHICH_OPTIONAL)
+#endif
     {
       size_t iChoose = 0;
       int iLen = lstrlenW(lpszPath);
       if (iLen > (MAX_PATH - 5))
         return FALSE;
+#ifndef __REACTOS__
       while ( (dwWhich & 0x1) && pszExts[iChoose][0] )
+#else
+      while (pszExts[iChoose][0])
+#endif
       {
+#ifdef __REACTOS__
+        if (dwWhich & 0x1)
+        {
+#endif
         lstrcpyW(lpszPath + iLen, pszExts[iChoose]);
         if (PathFileExistsW(lpszPath))
           return TRUE;
+#ifdef __REACTOS__
+        }
+#endif
         iChoose++;
         dwWhich >>= 1;
       }