[SHLWAPI][SHLWAPI_APITEST][SDK] Support CharLowerNoDBCSA/W and CharUpperNoDBCSA/W (#8920)

Implementing missing features...
JIRA issue: CORE-19278
- Implement CharLowerNoDBCSA, CharLowerNoDBCSW,
  CharUpperNoDBCSA, and CharUpperNoDBCSW functions.
- Modify shlwapi.spec.
- Add prototypes into <shlwapi_undoc.h>.
- Add CharUpperNoDBCS testcase.

dll/win32/shlwapi/shlwapi.spec

@@ -448,10 +448,10 @@
 448 stdcall -noname FixSlashesAndColonW(wstr)
 449 stub -noname NextPathA
 450 stub -noname NextPathW
-451 stub -noname CharUpperNoDBCSA
-452 stub -noname CharUpperNoDBCSW
-453 stub -noname CharLowerNoDBCSA
-454 stub -noname CharLowerNoDBCSW
+451 stdcall -noname CharUpperNoDBCSA(str)
+452 stdcall -noname CharUpperNoDBCSW(wstr)
+453 stdcall -noname CharLowerNoDBCSA(str)
+454 stdcall -noname CharLowerNoDBCSW(wstr)
 455 stdcall -noname PathIsValidCharA(long long)
 456 stdcall -noname PathIsValidCharW(long long)
 457 stdcall -noname GetLongPathNameWrapW(wstr ptr long) kernel32.GetLongPathNameW

dll/win32/shlwapi/utils.cpp

@@ -41,6 +41,64 @@ GetVersionMajorMinor()
     return MAKEWORD(HIBYTE(version), LOBYTE(version));
 }
 
+static BOOL CharLowerNoDBCSAWorker(PSTR lpString, INT cchMax, BOOL bUppercase)
+{
+    CHAR szBuff[MAX_PATH];
+    INT cch;
+    if (!lpString)
+        return FALSE;
+    cch = cchMax ? cchMax : lstrlenA(lpString);
+    if (FAILED(StringCchCopyA(szBuff, _countof(szBuff), lpString)))
+        return FALSE;
+    return LCMapStringA(LOCALE_SYSTEM_DEFAULT, (bUppercase ? LCMAP_UPPERCASE : LCMAP_LOWERCASE),
+                        szBuff, cch, lpString, cch);
+}
+
+static BOOL CharLowerNoDBCSWWorker(PWSTR lpString, INT cchMax, BOOL bUppercase)
+{
+    WCHAR szDest[MAX_PATH];
+    INT cch;
+    if (!lpString)
+        return FALSE;
+    cch = cchMax ? cchMax : lstrlenW(lpString);
+    if (FAILED(StringCchCopyW(szDest, _countof(szDest), lpString)))
+        return FALSE;
+    return LCMapStringW(LOCALE_SYSTEM_DEFAULT, (bUppercase ? LCMAP_UPPERCASE : LCMAP_LOWERCASE),
+                        szDest, cch, lpString, cch);
+}
+
+/*************************************************************************
+ * CharLowerNoDBCSA [SHLWAPI.453]
+ */
+EXTERN_C PSTR WINAPI CharLowerNoDBCSA(_Inout_ PSTR lpString)
+{
+    return CharLowerNoDBCSAWorker(lpString, 0, FALSE) ? lpString : NULL;
+}
+
+/*************************************************************************
+ * CharLowerNoDBCSW [SHLWAPI.454]
+ */
+EXTERN_C PWSTR WINAPI CharLowerNoDBCSW(_Inout_ PWSTR lpString)
+{
+    return CharLowerNoDBCSWWorker(lpString, 0, FALSE) ? lpString : NULL;
+}
+
+/*************************************************************************
+ * CharUpperNoDBCSA [SHLWAPI.451]
+ */
+EXTERN_C PSTR WINAPI CharUpperNoDBCSA(_Inout_ PSTR lpString)
+{
+    return CharLowerNoDBCSAWorker(lpString, 0, TRUE) ? lpString : NULL;
+}
+
+/*************************************************************************
+ * CharUpperNoDBCSW [SHLWAPI.452]
+ */
+EXTERN_C PWSTR WINAPI CharUpperNoDBCSW(_Inout_ PWSTR lpString)
+{
+    return CharLowerNoDBCSWWorker(lpString, 0, TRUE) ? lpString : NULL;
+}
+
 static HRESULT
 SHInvokeCommandOnContextMenuInternal(
     _In_opt_ HWND hWnd,

modules/rostests/apitests/shlwapi/CMakeLists.txt

@@ -6,6 +6,7 @@ include_directories($<TARGET_FILE_DIR:shlwapi_resource_dll>)
 
 list(APPEND SOURCE
     AssocQueryString.c
+    CharUpperNoDBCS.cpp
     IShellFolderHelpers.cpp
     IsQSForward.cpp
     IStreamPidl.cpp

modules/rostests/apitests/shlwapi/CharUpperNoDBCS.cpp

@@ -0,0 +1,276 @@
+/*
+ * PROJECT:     ReactOS api tests
+ * LICENSE:     GPL-2.0-or-later (https://spdx.org/licenses/GPL-2.0-or-later)
+ * PURPOSE:     Tests for CharUpperNoDBCSA/W and CharLowerNoDBCSA/W
+ * COPYRIGHT:   Copyright 2026 Katayama Hirofumi MZ <katayama.hirofumi.mz@gmail.com>
+ */
+
+#include <apitest.h>
+#include <shlwapi.h>
+#include <string.h>
+#include <wchar.h>
+
+typedef PSTR  (WINAPI *FN_CharLowerNoDBCSA)(PSTR);
+typedef PWSTR (WINAPI *FN_CharLowerNoDBCSW)(PWSTR);
+typedef PSTR  (WINAPI *FN_CharUpperNoDBCSA)(PSTR);
+typedef PWSTR (WINAPI *FN_CharUpperNoDBCSW)(PWSTR);
+
+static FN_CharLowerNoDBCSA g_fnCharLowerNoDBCSA = NULL;
+static FN_CharLowerNoDBCSW g_fnCharLowerNoDBCSW = NULL;
+static FN_CharUpperNoDBCSA g_fnCharUpperNoDBCSA = NULL;
+static FN_CharUpperNoDBCSW g_fnCharUpperNoDBCSW = NULL;
+
+static void Test_CharUpperNoDBCSA(void)
+{
+    // Basic ASCII lowercase → uppercase
+    {
+        char buf[] = "hello world";
+        PSTR ret = g_fnCharUpperNoDBCSA(buf);
+        ok(ret == buf, "ret was %p\n", ret);
+        ok_str(buf, "HELLO WORLD");
+    }
+
+    // Already uppercase → unchanged
+    {
+        char buf[] = "HELLO WORLD";
+        g_fnCharUpperNoDBCSA(buf);
+        ok_str(buf, "HELLO WORLD");
+    }
+
+    // Mixed case
+    {
+        char buf[] = "Hello World";
+        g_fnCharUpperNoDBCSA(buf);
+        ok_str(buf, "HELLO WORLD");
+    }
+
+    // Digits and symbols are unchanged
+    {
+        char buf[] = "abc123!@#";
+        g_fnCharUpperNoDBCSA(buf);
+        ok_str(buf, "ABC123!@#");
+    }
+
+    // Empty string
+    {
+        char buf[] = "";
+        PCSTR ret = g_fnCharUpperNoDBCSA(buf);
+        ok(ret == NULL, "ret was not NULL.\n");
+        ok_int(buf[0], ANSI_NULL);
+    }
+
+    // NULL pointer → must return NULL without crashing
+    {
+        PSTR ret = g_fnCharUpperNoDBCSA(NULL);
+        ok(ret == NULL, "ret was %p\n", ret);
+    }
+}
+
+static void Test_CharLowerNoDBCSA(void)
+{
+    // Basic ASCII uppercase → lowercase
+    {
+        char buf[] = "HELLO WORLD";
+        PSTR ret = g_fnCharLowerNoDBCSA(buf);
+        ok(ret == buf, "ret was %p\n", ret);
+        ok_str(buf, "hello world");
+    }
+
+    // Already lowercase → unchanged
+    {
+        char buf[] = "hello world";
+        g_fnCharLowerNoDBCSA(buf);
+        ok_str(buf, "hello world");
+    }
+
+    // Mixed case
+    {
+        char buf[] = "Hello World";
+        g_fnCharLowerNoDBCSA(buf);
+        ok_str(buf, "hello world");
+    }
+
+    // Digits and symbols are unchanged
+    {
+        char buf[] = "ABC123!@#";
+        g_fnCharLowerNoDBCSA(buf);
+        ok_str(buf, "abc123!@#");
+    }
+
+    // Empty string
+    {
+        char buf[] = "";
+        PCSTR ret = g_fnCharLowerNoDBCSA(buf);
+        ok(ret == NULL, "ret was not NULL.\n");
+        ok_int(buf[0], ANSI_NULL);
+    }
+
+    // NULL pointer → must return NULL without crashing
+    {
+        PSTR ret = g_fnCharLowerNoDBCSA(NULL);
+        ok(ret == NULL, "ret was %p\n", ret);
+    }
+}
+
+static void Test_CharUpperNoDBCSW(void)
+{
+    // Basic ASCII lowercase → uppercase (wide)
+    {
+        wchar_t buf[] = L"hello world";
+        PWSTR ret = g_fnCharUpperNoDBCSW(buf);
+        ok(ret == buf, "ret was %p\n", ret);
+        ok_wstr(buf, L"HELLO WORLD");
+    }
+
+    // Already uppercase → unchanged
+    {
+        wchar_t buf[] = L"HELLO WORLD";
+        g_fnCharUpperNoDBCSW(buf);
+        ok_wstr(buf, L"HELLO WORLD");
+    }
+
+    // Mixed case
+    {
+        wchar_t buf[] = L"Hello World";
+        g_fnCharUpperNoDBCSW(buf);
+        ok_wstr(buf, L"HELLO WORLD");
+    }
+
+    // Digits and symbols are unchanged
+    {
+        wchar_t buf[] = L"abc123!@#";
+        g_fnCharUpperNoDBCSW(buf);
+        ok_wstr(buf, L"ABC123!@#");
+    }
+
+    // Empty string
+    {
+        wchar_t buf[] = L"";
+        PCWSTR ret = g_fnCharUpperNoDBCSW(buf);
+        ok(ret == NULL, "ret was not NULL.\n");
+        ok_int(buf[0], UNICODE_NULL);
+    }
+
+    // NULL pointer → must return NULL without crashing
+    {
+        PWSTR ret = g_fnCharUpperNoDBCSW(NULL);
+        ok(ret == NULL, "ret was %p\n", ret);
+    }
+}
+
+static void Test_CharLowerNoDBCSW(void)
+{
+    // Basic ASCII uppercase → lowercase (wide)
+    {
+        wchar_t buf[] = L"HELLO WORLD";
+        PWSTR ret = g_fnCharLowerNoDBCSW(buf);
+        ok(ret == buf, "ret was %p\n", ret);
+        ok_wstr(buf, L"hello world");
+    }
+
+    // Already lowercase → unchanged
+    {
+        wchar_t buf[] = L"hello world";
+        g_fnCharLowerNoDBCSW(buf);
+        ok_wstr(buf, L"hello world");
+    }
+
+    // Mixed case
+    {
+        wchar_t buf[] = L"Hello World";
+        g_fnCharLowerNoDBCSW(buf);
+        ok_wstr(buf, L"hello world");
+    }
+
+    // Digits and symbols are unchanged
+    {
+        wchar_t buf[] = L"ABC123!@#";
+        g_fnCharLowerNoDBCSW(buf);
+        ok_wstr(buf, L"abc123!@#");
+    }
+
+    // Empty string
+    {
+        wchar_t buf[] = L"";
+        PCWSTR ret = g_fnCharLowerNoDBCSW(buf);
+        ok(ret == NULL, "ret was not NULL.\n");
+        ok_int(buf[0], UNICODE_NULL);
+    }
+
+    // NULL pointer → must return NULL without crashing
+    {
+        PWSTR ret = g_fnCharLowerNoDBCSW(NULL);
+        ok(ret == NULL, "ret was %p\n", ret);
+    }
+}
+
+static void Test_RoundTrip(void)
+{
+    {
+        char upper[] = "Hello World 123";
+        char lower[] = "Hello World 123";
+        g_fnCharUpperNoDBCSA(upper);        // "HELLO WORLD 123"
+        g_fnCharLowerNoDBCSA(lower);        // "hello world 123"
+
+        char rt1[] = "hello world 123";
+        g_fnCharUpperNoDBCSA(rt1);          // Lower then Upper → "HELLO WORLD 123"
+        ok_str(rt1, upper);
+
+        char rt2[] = "HELLO WORLD 123";
+        g_fnCharLowerNoDBCSA(rt2);          // Upper then Lower → "hello world 123"
+        ok_str(rt2, lower);
+    }
+
+    {
+        wchar_t upper[] = L"Hello World 123";
+        wchar_t lower[] = L"Hello World 123";
+        g_fnCharUpperNoDBCSW(upper);
+        g_fnCharLowerNoDBCSW(lower);
+
+        wchar_t rt1[] = L"hello world 123";
+        g_fnCharUpperNoDBCSW(rt1);
+        ok_wstr(rt1, upper);
+
+        wchar_t rt2[] = L"HELLO WORLD 123";
+        g_fnCharLowerNoDBCSW(rt2);
+        ok_wstr(rt2, lower);
+    }
+}
+
+static void Test_NoDBCS(void)
+{
+    BYTE buf[] = { 0x82, 'a', ANSI_NULL };
+    g_fnCharUpperNoDBCSA((PSTR)buf);
+    ok_int(buf[2], ANSI_NULL);
+}
+
+START_TEST(CharUpperNoDBCS)
+{
+    HINSTANCE hSHLWAPI = LoadLibraryW(L"shlwapi");
+    if (!hSHLWAPI)
+    {
+        skip("shlwapi not found\n");
+        return;
+    }
+
+    g_fnCharLowerNoDBCSA = (FN_CharLowerNoDBCSA)GetProcAddress(hSHLWAPI, MAKEINTRESOURCEA(453));
+    g_fnCharLowerNoDBCSW = (FN_CharLowerNoDBCSW)GetProcAddress(hSHLWAPI, MAKEINTRESOURCEA(454));
+    g_fnCharUpperNoDBCSA = (FN_CharUpperNoDBCSA)GetProcAddress(hSHLWAPI, MAKEINTRESOURCEA(451));
+    g_fnCharUpperNoDBCSW = (FN_CharUpperNoDBCSW)GetProcAddress(hSHLWAPI, MAKEINTRESOURCEA(452));
+    if (!g_fnCharLowerNoDBCSA || !g_fnCharLowerNoDBCSW ||
+        !g_fnCharUpperNoDBCSA || !g_fnCharUpperNoDBCSW)
+    {
+        skip("CharUpperNoDBCSA/W or CharLowerNoDBCSA/W not found\n");
+        FreeLibrary(hSHLWAPI);
+        return;
+    }
+
+    Test_CharUpperNoDBCSA();
+    Test_CharLowerNoDBCSA();
+    Test_CharUpperNoDBCSW();
+    Test_CharLowerNoDBCSW();
+    Test_RoundTrip();
+    Test_NoDBCS();
+
+    FreeLibrary(hSHLWAPI);
+}

modules/rostests/apitests/shlwapi/testlist.c

@@ -2,6 +2,7 @@
 #include <apitest.h>
 
 extern void func_AssocQueryString(void);
+extern void func_CharUpperNoDBCS(void);
 extern void func_PathFileExistsDefExtAndAttributesW(void);
 extern void func_PathFindOnPath(void);
 extern void func_IShellFolderHelpers(void);
@@ -24,6 +25,7 @@ extern void func_StrToInt(void);
 const struct test winetest_testlist[] =
 {
     { "AssocQueryString", func_AssocQueryString },
+    { "CharUpperNoDBCS", func_CharUpperNoDBCS },
     { "PathFileExistsDefExtAndAttributesW", func_PathFileExistsDefExtAndAttributesW },
     { "PathFindOnPath", func_PathFindOnPath },
     { "IShellFolderHelpers", func_IShellFolderHelpers },

sdk/include/reactos/shlwapi_undoc.h

@@ -129,6 +129,11 @@ MayExecForward(
     _In_ VARIANT *pvaIn,
     _Inout_ VARIANT *pvaOut);
 
+PSTR WINAPI CharLowerNoDBCSA(_Inout_ PSTR lpString);
+PWSTR WINAPI CharLowerNoDBCSW(_Inout_ PWSTR lpString);
+PSTR WINAPI CharUpperNoDBCSA(_Inout_ PSTR lpString);
+PWSTR WINAPI CharUpperNoDBCSW(_Inout_ PWSTR lpString);
+
 HRESULT WINAPI IsQSForward(_In_opt_ REFGUID pguidCmdGroup, _In_ ULONG cCmds, _In_ OLECMD *prgCmds);
 BOOL WINAPI SHIsChildOrSelf(HWND hParent, HWND hChild);
 HRESULT WINAPI SHForwardContextMenuMsg(IUnknown* pUnk, UINT uMsg, WPARAM wParam, LPARAM lParam, LRESULT* pResult, BOOL useIContextMenu2);