[SHELL32][SHELL32_APITEST][SDK] Implement SHSetUnreadMailCountW (#7620)

Implementing missing features...
JIRA issue: CORE-19278
- Move function definition from
  stubs.cpp into utils.cpp.
- Add prototype to <shellapi.h>.

dll/win32/shell32/stubs.cpp

@@ -30,19 +30,6 @@ SHGetUnreadMailCountW(HKEY hKeyUser,
     return E_FAIL;
 }
 
-/*
- * Unimplemented
- */
-EXTERN_C HRESULT
-WINAPI
-SHSetUnreadMailCountW(LPCWSTR pszMailAddress,
-                      DWORD dwCount,
-                      LPCWSTR pszShellExecuteCommand)
-{
-    FIXME("SHSetUnreadMailCountW() stub\n");
-    return E_FAIL;
-}
-
 /*
  * Unimplemented
  */

dll/win32/shell32/utils.cpp

@@ -796,6 +796,64 @@ SHCreatePropertyBag(_In_ REFIID riid, _Out_ void **ppvObj)
     return SHCreatePropertyBagOnMemory(STGM_READWRITE, riid, ppvObj);
 }
 
+/*************************************************************************
+ *  SHSetUnreadMailCountW [SHELL32.336]
+ *
+ * @see https://learn.microsoft.com/en-us/windows/win32/api/shellapi/nf-shellapi-shsetunreadmailcountw
+ */
+EXTERN_C
+HRESULT WINAPI
+SHSetUnreadMailCountW(
+    _In_ PCWSTR pszMailAddress,
+    _In_ DWORD dwCount,
+    _In_ PCWSTR pszShellExecuteCommand)
+{
+    CString strKey = L"Software\\Microsoft\\Windows\\CurrentVersion\\UnreadMail";
+    strKey += L'\\';
+    strKey += pszMailAddress;
+
+    HKEY hKey;
+    DWORD dwDisposition;
+    LSTATUS error = RegCreateKeyExW(HKEY_CURRENT_USER, strKey, 0, NULL, 0, KEY_SET_VALUE, NULL,
+                                    &hKey, &dwDisposition);
+    if (error)
+        return HRESULT_FROM_WIN32(error);
+
+    error = RegSetValueExW(hKey, L"MessageCount", 0, REG_DWORD, (PBYTE)&dwCount, sizeof(dwCount));
+    if (error)
+    {
+        RegCloseKey(hKey);
+        return HRESULT_FROM_WIN32(error);
+    }
+
+    FILETIME FileTime;
+    GetSystemTimeAsFileTime(&FileTime);
+
+    error = RegSetValueExW(hKey, L"TimeStamp", 0, REG_BINARY, (PBYTE)&FileTime, sizeof(FileTime));
+    if (error)
+    {
+        RegCloseKey(hKey);
+        return HRESULT_FROM_WIN32(error);
+    }
+
+    WCHAR szBuff[2 * MAX_PATH];
+    if (!PathUnExpandEnvStringsW(pszShellExecuteCommand, szBuff, _countof(szBuff)))
+    {
+        HRESULT hr = StringCchCopyW(szBuff, _countof(szBuff), pszShellExecuteCommand);
+        if (FAILED_UNEXPECTEDLY(hr))
+        {
+            RegCloseKey(hKey);
+            return hr;
+        }
+    }
+
+    DWORD cbValue = (lstrlenW(szBuff) + 1) * sizeof(WCHAR);
+    error = RegSetValueExW(hKey, L"Application", 0, REG_SZ, (PBYTE)szBuff, cbValue);
+
+    RegCloseKey(hKey);
+    return (error ? HRESULT_FROM_WIN32(error) : S_OK);
+}
+
 /*************************************************************************
  *                SheRemoveQuotesA (SHELL32.@)
  */

modules/rostests/apitests/shell32/CMakeLists.txt

@@ -45,6 +45,7 @@ list(APPEND SOURCE
     SHGetAttributesFromDataObject.cpp
     SHGetUserDisplayName.cpp
     SHLimitInputEdit.cpp
+    SHSetUnreadMailCountW.cpp
     menu.cpp
     shelltest.cpp)
 

modules/rostests/apitests/shell32/SHSetUnreadMailCountW.cpp

@@ -0,0 +1,58 @@
+/*
+ * PROJECT:     ReactOS API tests
+ * LICENSE:     GPL-2.0+ (https://spdx.org/licenses/GPL-2.0+)
+ * PURPOSE:     Test for SHSetUnreadMailCountW
+ * COPYRIGHT:   Copyright 2025 Katayama Hirofumi MZ (katayama.hirofumi.mz@gmail.com)
+ */
+
+#include "shelltest.h"
+
+START_TEST(SHSetUnreadMailCountW)
+{
+    HKEY hKey;
+    LSTATUS error;
+    DWORD dwDisposition;
+    error = RegCreateKeyExW(HKEY_CURRENT_USER,
+                            L"Software\\Microsoft\\Windows\\CurrentVersion\\UnreadMail\\example.com",
+                            0, NULL, 0, KEY_WRITE, NULL, &hKey, &dwDisposition);
+    ok_long(error, ERROR_SUCCESS);
+    RegCloseKey(hKey);
+
+    HRESULT hr = SHSetUnreadMailCountW(L"example.com", 1, L"MyMailerApp");
+    ok_hex(hr, S_OK);
+
+    error = RegOpenKeyExW(HKEY_CURRENT_USER,
+                          L"Software\\Microsoft\\Windows\\CurrentVersion\\UnreadMail\\example.com",
+                          0,
+                          KEY_READ,
+                          &hKey);
+    ok_long(error, ERROR_SUCCESS);
+
+    DWORD dwValue, cbValue = sizeof(dwValue);
+    error = RegQueryValueExW(hKey, L"MessageCount", NULL, NULL, (PBYTE)&dwValue, &cbValue);
+    ok_long(error, ERROR_SUCCESS);
+    ok_long(dwValue, 1);
+
+    FILETIME FileTime;
+    cbValue = sizeof(FileTime);
+    error = RegQueryValueExW(hKey, L"TimeStamp", NULL, NULL, (PBYTE)&FileTime, &cbValue);
+    ok_long(error, ERROR_SUCCESS);
+    ok(FileTime.dwHighDateTime != 0, "FileTime.dwHighDateTime was zero\n");
+
+    WCHAR szValue[MAX_PATH];
+    cbValue = sizeof(szValue);
+    error = RegQueryValueExW(hKey, L"Application", NULL, NULL, (PBYTE)szValue, &cbValue);
+    ok_long(error, ERROR_SUCCESS);
+    ok_wstr(szValue, L"MyMailerApp");
+
+    RegCloseKey(hKey);
+
+    hr = SHSetUnreadMailCountW(L"example.com", 0, L"MyMailerApp");
+    ok_hex(hr, S_OK);
+
+    if (dwDisposition == REG_CREATED_NEW_KEY)
+    {
+        RegDeleteKeyW(HKEY_CURRENT_USER,
+                      L"Software\\Microsoft\\Windows\\CurrentVersion\\UnreadMail\\example.com");
+    }
+}

modules/rostests/apitests/shell32/testlist.c

@@ -49,6 +49,7 @@ extern void func_SHParseDisplayName(void);
 extern void func_SHShouldShowWizards(void);
 extern void func_SHSimpleIDListFromPath(void);
 extern void func_SHRestricted(void);
+extern void func_SHSetUnreadMailCountW(void);
 
 const struct test winetest_testlist[] =
 {
@@ -98,6 +99,7 @@ const struct test winetest_testlist[] =
     { "SHShouldShowWizards", func_SHShouldShowWizards },
     { "SHSimpleIDListFromPath", func_SHSimpleIDListFromPath },
     { "SHRestricted", func_SHRestricted },
+    { "SHSetUnreadMailCountW", func_SHSetUnreadMailCountW },
 
     { 0, 0 }
 };

sdk/include/psdk/shellapi.h

@@ -638,6 +638,12 @@ DoEnvironmentSubstW(
     _Inout_updates_(cchSrc) LPWSTR pszSrc,
     UINT cchSrc);
 
+HRESULT WINAPI
+SHSetUnreadMailCountW(
+    _In_ PCWSTR pszMailAddress,
+    _In_ DWORD dwCount,
+    _In_ PCWSTR pszShellExecuteCommand);
+
 #if (_WIN32_IE >= 0x0601)
 BOOL
 WINAPI