[win32] Always call SetLastError(ERROR_SUCCESS) before GetModuleFileN…

…ame().

Windows XP doesn't call SetLastError() in GetModuleFileName() at all,
so it's possible that a previous error could show up here. In this case,
RegKey::RegisterComObject() was getting error 127 (ERROR_PROC_NOT_FOUND),
which prevented registering rom-properties.dll on Windows XP.

I'm not sure when exactly this showed up, since it could be completely
random depending on GetProcAddress() usage.

Interestingly, a few files already called SetLastError(ERROR_SUCCESS):
- i18n.c
- DelayLoadHelper.c
- DllMain.cpp

src/libi18n/i18n.c

@@ -63,7 +63,7 @@ static void rp_i18n_init_int(void)
 	// Get the current module filename.
 	// NOTE: Delay-load only supports ANSI module names.
 	// We'll assume it's ASCII and do a simple conversion to Unicode.
-	SetLastError(ERROR_SUCCESS);
+	SetLastError(ERROR_SUCCESS);	// required for XP
 	dwResult = GetModuleFileName(HINST_THISCOMPONENT,
 		tpathname, ARRAY_SIZE(tpathname));
 	if (dwResult == 0 || GetLastError() != ERROR_SUCCESS) {

src/libromdata/data/AmiiboData.cpp

@@ -194,6 +194,7 @@ string AmiiboDataPrivate::getAmiiboBinFilename(AmiiboBinFileType amiiboBinFileTy
 			filename = DIR_INSTALL_SHARE DIR_SEP_STR AMIIBO_BIN_FILENAME;
 #elif defined(_WIN32)
 			TCHAR dll_filename[MAX_PATH];
+			SetLastError(ERROR_SUCCESS);	// required for XP
 			DWORD dwResult = GetModuleFileName(HINST_THISCOMPONENT,
 				dll_filename, _countof(dll_filename));
 			if (dwResult == 0 || GetLastError() != ERROR_SUCCESS) {

src/libromdata/img/ExecRpDownload_win32.cpp

@@ -2,7 +2,7 @@
  * ROM Properties Page shell extension. (libromdata)                       *
  * ExecRpDownload_win32.cpp: Execute rp-download.exe. (Win32)              *
  *                                                                         *
- * Copyright (c) 2016-2020 by David Korth.                                 *
+ * Copyright (c) 2016-2022 by David Korth.                                 *
  * SPDX-License-Identifier: GPL-2.0-or-later                               *
  ***************************************************************************/
 
@@ -32,6 +32,7 @@ int CacheManager::execRpDownload(const string &filteredCacheKey)
 {
 	// The executable should be located in the DLL directory.
 	TCHAR dll_filename[MAX_PATH];
+	SetLastError(ERROR_SUCCESS);	// required for XP
 	DWORD dwResult = GetModuleFileName(HINST_THISCOMPONENT,
 		dll_filename, _countof(dll_filename));
 	if (dwResult == 0 || GetLastError() != ERROR_SUCCESS) {

src/libwin32common/DelayLoadHelper.c

@@ -105,7 +105,7 @@ static HMODULE WINAPI rp_loadLibrary(LPCSTR pszModuleName)
 
 	// NOTE: Delay-load only supports ANSI module names.
 	// We'll assume it's ASCII and do a simple conversion to Unicode.
-	SetLastError(ERROR_SUCCESS);
+	SetLastError(ERROR_SUCCESS);	// required for XP
 	dwResult = GetModuleFileName(HINST_THISCOMPONENT,
 		dll_fullpath, _countof(dll_fullpath));
 	if (dwResult == 0 || GetLastError() != ERROR_SUCCESS) {

src/libwin32common/RegKey.cpp

@@ -669,6 +669,7 @@ LONG RegKey::RegisterComObject(HINSTANCE hInstance, REFCLSID rclsid,
 	// Set the default value to the filename of the specified DLL.
 	// TODO: Duplicated from win32/. Consolidate the two?
 	TCHAR dll_filename[MAX_PATH];
+	SetLastError(ERROR_SUCCESS);	// required for XP
 	DWORD dwResult = GetModuleFileName(hInstance, dll_filename, _countof(dll_filename));
 	if (dwResult == 0 || GetLastError() != ERROR_SUCCESS) {
 		// Cannot get the DLL filename.

src/svrplus/svrplus.c

@@ -287,6 +287,7 @@ static InstallServerResult InstallServer(bool isUninstall, bool is64, DWORD *pEr
 
 	// Construct arguments
 	// Construct path to rom-properties.dll inside the arguments
+	SetLastError(ERROR_SUCCESS);	// required for XP
 	szModuleFn = GetModuleFileName(HINST_THISCOMPONENT, &args[14], MAX_PATH);
 	assert(szModuleFn != 0);
 	assert(szModuleFn < MAX_PATH);

src/win32/DllMain.cpp

@@ -71,7 +71,7 @@ BOOL WINAPI DllMain(HINSTANCE hInstance, DWORD dwReason, LPVOID /*lpReserved*/)
 	switch (dwReason) {
 		case DLL_PROCESS_ATTACH: {
 			// Get the DLL filename.
-			SetLastError(ERROR_SUCCESS);
+			SetLastError(ERROR_SUCCESS);	// required for XP
 			DWORD dwResult = GetModuleFileName(hInstance,
 				dll_filename, _countof(dll_filename));
 			if (dwResult == 0 || GetLastError() != ERROR_SUCCESS) {

src/win32/config/rp-config.c

@@ -153,6 +153,7 @@ int CALLBACK WinMain(_In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance,
 	exe_path = malloc(MAX_PATH*sizeof(TCHAR));
 	if (!exe_path)
 		FAIL_MESSAGE(_T("Failed to allocate memory for the EXE path."));
+	SetLastError(ERROR_SUCCESS);	// required for XP
 	exe_path_len = GetModuleFileName(hInstance, exe_path, EXE_PATH_LEN);
 	if (exe_path_len == 0 || exe_path_len >= EXE_PATH_LEN)
 		FAIL_MESSAGE(_T("Failed to get the EXE path."));