Make Environment singleton

CrendKing · Apr 21, 2021 · 9261c7b · 9261c7b
1 parent 781d475
commit 9261c7b
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Showing 5 changed files with 60 additions and 58 deletions.
diff --git a/src/environment.cpp b/src/environment.cpp
@@ -6,15 +6,20 @@ static constexpr const WCHAR *SELECTED_ITEM_OBJECT_NAME = L"Global\\CompareMenuS
 
 static std::array<WCHAR, MAX_PATH> g_quotedPathBuffer {};
 
-std::wstring Environment::modulePath;
-std::wstring Environment::comparerPath;
-std::wstring Environment::comparerArgs;
-Item Environment::selectedItem;
-HANDLE Environment::_hMapFile = nullptr;
-LPWSTR Environment::_mappingBuffer = nullptr;
+Environment::Environment() {
+    modulePath.resize(MAX_PATH);
+}
+
+Environment::~Environment() {
+    if (_mappingBuffer != nullptr) {
+        UnmapViewOfFile(_mappingBuffer);
+    }
+    if (_hMapFile != nullptr) {
+        CloseHandle(_hMapFile);
+    }
+}
 
 auto Environment::Initialize(HINSTANCE hInstance) -> bool {
-    modulePath.resize(MAX_PATH);
     if (GetModuleFileNameW(hInstance, modulePath.data(), static_cast<DWORD>(modulePath.size())) == 0) {
         return false;
     }
@@ -35,16 +40,7 @@ auto Environment::Initialize(HINSTANCE hInstance) -> bool {
     return true;
 }
 
-auto Environment::Destroy() -> void {
-    if (_mappingBuffer != nullptr) {
-        UnmapViewOfFile(_mappingBuffer);
-    }
-    if (_hMapFile != nullptr) {
-        CloseHandle(_hMapFile);
-    }
-}
-
-auto Environment::QuotePath(PCWSTR path) -> const WCHAR * {
+auto Environment::QuotePath(PCWSTR path) const -> const WCHAR * {
     if (path == nullptr) {
         return path;
     }
@@ -61,7 +57,7 @@ auto Environment::LoadSelectedItem() -> void {
     }
 }
 
-auto Environment::FlushSelectedItem() -> void {
+auto Environment::FlushSelectedItem() const -> void {
     if (selectedItem.name.empty()) {
         CopyMemory(_mappingBuffer, L"\0", sizeof(WCHAR));
     } else {

diff --git a/src/environment.h b/src/environment.h
@@ -4,23 +4,23 @@
 
 
 struct Environment {
-    static auto Initialize(HINSTANCE hInstance) -> bool;
-    static auto Destroy() -> void;
+    static inline std::unique_ptr<Environment> INSTANCE;
 
-    static auto QuotePath(PCWSTR path) -> const WCHAR *;
-    static auto LoadSelectedItem() -> void;
-    static auto FlushSelectedItem() -> void;
+    Environment();
+    ~Environment();
 
-    static constexpr const WCHAR *COMPARER_ARGS_LEFT_PLACEHOLDER = L"%LEFT%";
-    static constexpr const WCHAR *COMPARER_ARGS_RIGHT_PLACEHOLDER = L"%RIGHT%";
+    auto Initialize(HINSTANCE hInstance) -> bool;
+    auto QuotePath(PCWSTR path) const -> const WCHAR *;
+    auto LoadSelectedItem() -> void;
+    auto FlushSelectedItem() const -> void;
 
-    static std::wstring modulePath;
-    static std::wstring comparerPath;
-    static std::wstring comparerArgs;
+    std::wstring modulePath;
+    std::wstring comparerPath;
+    std::wstring comparerArgs;
 
-    static Item selectedItem;
+    Item selectedItem;
 
 private:
-    static HANDLE _hMapFile;
-    static LPWSTR _mappingBuffer;
+    HANDLE _hMapFile = nullptr;
+    LPWSTR _mappingBuffer = nullptr;
 };
diff --git a/src/menu.cpp b/src/menu.cpp
@@ -13,18 +13,18 @@ auto STDMETHODCALLTYPE CCompareMenu::Initialize(__RPC__in_string LPCWSTR pszComm
     ATL::CComVariant variant;
 
     if (SUCCEEDED(ppb->Read(REGISTRY_COMPARER_PATH_VALUE_NAME, &variant, nullptr))) {
-        Environment::comparerPath = variant.bstrVal;
+        Environment::INSTANCE->comparerPath = variant.bstrVal;
     } else {
-        Environment::comparerPath.clear();
+        Environment::INSTANCE->comparerPath.clear();
     }
 
     if (SUCCEEDED(ppb->Read(REGISTRY_COMPARER_ARGS_VALUE_NAME, &variant, nullptr))) {
-        Environment::comparerArgs = variant.bstrVal;
+        Environment::INSTANCE->comparerArgs = variant.bstrVal;
     } else {
-        Environment::comparerArgs.clear();
+        Environment::INSTANCE->comparerArgs.clear();
     }
 
-    Environment::LoadSelectedItem();
+    Environment::INSTANCE->LoadSelectedItem();
 
     return S_OK;
 }
@@ -34,7 +34,7 @@ auto STDMETHODCALLTYPE CCompareMenu::GetTitle(__RPC__in_opt IShellItemArray *psi
 }
 
 auto STDMETHODCALLTYPE CCompareMenu::GetIcon(__RPC__in_opt IShellItemArray *psiItemArray, __RPC__deref_out_opt_string LPWSTR *ppszIcon) -> HRESULT {
-    return SHStrDupW((Environment::modulePath + L",0").c_str(), ppszIcon);
+    return SHStrDupW((Environment::INSTANCE->modulePath + L",0").c_str(), ppszIcon);
 }
 
 auto STDMETHODCALLTYPE CCompareMenu::GetToolTip(__RPC__in_opt IShellItemArray *psiItemArray, __RPC__deref_out_opt_string LPWSTR *ppszInfotip) -> HRESULT {
@@ -46,7 +46,7 @@ auto STDMETHODCALLTYPE CCompareMenu::GetCanonicalName(__RPC__out GUID *pguidComm
 }
 
 auto STDMETHODCALLTYPE CCompareMenu::GetState(__RPC__in_opt IShellItemArray *psiItemArray, BOOL fOkToBeSlow, __RPC__out EXPCMDSTATE *pCmdState) -> HRESULT {
-    *pCmdState = Environment::comparerPath.empty() || Environment::comparerArgs.empty() ? ECS_DISABLED : ECS_ENABLED;
+    *pCmdState = Environment::INSTANCE->comparerPath.empty() || Environment::INSTANCE->comparerArgs.empty() ? ECS_DISABLED : ECS_ENABLED;
     return S_OK;
 }
 

diff --git a/src/module.cpp b/src/module.cpp
@@ -6,11 +6,14 @@ class DiffMenuModule : public ATL::CAtlDllModuleT<DiffMenuModule> {
 } g_module;
 
 extern "C" auto WINAPI DllMain(HINSTANCE hInstance, DWORD dwReason, LPVOID lpReserved) -> BOOL {
-    if (dwReason == DLL_PROCESS_ATTACH && !Environment::Initialize(hInstance)) {
-        return FALSE;
+    if (dwReason == DLL_PROCESS_ATTACH) {
+        Environment::INSTANCE->INSTANCE = std::make_unique<Environment>();
+        if (!Environment::INSTANCE->INSTANCE->Initialize(hInstance)) {
+            return FALSE;
+        }
     }
     if (dwReason == DLL_PROCESS_DETACH) {
-        Environment::Destroy();
+        Environment::INSTANCE->INSTANCE.reset();
     }
 
     return g_module.DllMain(dwReason, lpReserved);

diff --git a/src/sub_cmd.cpp b/src/sub_cmd.cpp
@@ -3,6 +3,9 @@
 #include "environment.h"
 
 
+static constexpr const WCHAR *COMPARER_ARGS_LEFT_PLACEHOLDER = L"%LEFT%";
+static constexpr const WCHAR *COMPARER_ARGS_RIGHT_PLACEHOLDER = L"%RIGHT%";
+
 #define CheckHr(expr) { hr = (expr); if (FAILED(hr)) { return hr; } }
 
 auto STDMETHODCALLTYPE CSubCommand::GetToolTip(__RPC__in_opt IShellItemArray *psiItemArray, __RPC__deref_out_opt_string LPWSTR *ppszInfotip) -> HRESULT {
@@ -25,12 +28,12 @@ auto STDMETHODCALLTYPE CSubCommand::EnumSubCommands(__RPC__deref_out_opt IEnumEx
 auto STDMETHODCALLTYPE CInfoSubCommand::GetTitle(__RPC__in_opt IShellItemArray *psiItemArray, __RPC__deref_out_opt_string LPWSTR *ppszName) -> HRESULT {
     std::wstring infoTitle;
 
-    if (Environment::selectedItem.name.empty()) {
+    if (Environment::INSTANCE->selectedItem.name.empty()) {
         infoTitle = L"None selected";
     } else {
-        infoTitle.append(Environment::selectedItem.name).append(L" (");
+        infoTitle.append(Environment::INSTANCE->selectedItem.name).append(L" (");
 
-        if (Environment::selectedItem.isFolder) {
+        if (Environment::INSTANCE->selectedItem.isFolder) {
             infoTitle += L"Folder)";
         } else {
             infoTitle += L"File)";
@@ -69,7 +72,7 @@ auto STDMETHODCALLTYPE CSelectSubCommand::GetTitle(__RPC__in_opt IShellItemArray
 }
 
 auto STDMETHODCALLTYPE CSelectSubCommand::GetIcon(__RPC__in_opt IShellItemArray *psiItemArray, __RPC__deref_out_opt_string LPWSTR *ppszIcon) -> HRESULT {
-    return SHStrDupW((Environment::modulePath + L",0").c_str(), ppszIcon);
+    return SHStrDupW((Environment::INSTANCE->modulePath + L",0").c_str(), ppszIcon);
 }
 
 auto STDMETHODCALLTYPE CSelectSubCommand::GetState(__RPC__in_opt IShellItemArray *psiItemArray, BOOL fOkToBeSlow, __RPC__out EXPCMDSTATE *pCmdState) -> HRESULT {
@@ -80,13 +83,13 @@ auto STDMETHODCALLTYPE CSelectSubCommand::GetState(__RPC__in_opt IShellItemArray
 
     if (itemCount != 1) {
         *pCmdState = ECS_HIDDEN;
-    } else if (Environment::selectedItem.name.empty()) {
+    } else if (Environment::INSTANCE->selectedItem.name.empty()) {
         *pCmdState = ECS_ENABLED;
     } else {
         Item currItem;
         CheckHr(currItem.ExtractItemAt(psiItemArray, 0));
 
-        *pCmdState = currItem.name == Environment::selectedItem.name ? ECS_HIDDEN : ECS_ENABLED;
+        *pCmdState = currItem.name == Environment::INSTANCE->selectedItem.name ? ECS_HIDDEN : ECS_ENABLED;
     }
 
     return S_OK;
@@ -102,8 +105,8 @@ auto STDMETHODCALLTYPE CSelectSubCommand::Invoke(__RPC__in_opt IShellItemArray *
         return E_UNEXPECTED;
     }
 
-    CheckHr(Environment::selectedItem.ExtractItemAt(psiItemArray, 0));
-    Environment::FlushSelectedItem();
+    CheckHr(Environment::INSTANCE->selectedItem.ExtractItemAt(psiItemArray, 0));
+    Environment::INSTANCE->FlushSelectedItem();
 
     return S_OK;
 }
@@ -120,11 +123,11 @@ auto CDiffSubCommand::ExtractItems(IShellItemArray *psiItemArray, Item &firstIte
     CheckHr(secondItem.ExtractItemAt(psiItemArray, 0));
 
     if (itemCount == 1) {
-        if (Environment::selectedItem.name.empty()) {
+        if (Environment::INSTANCE->selectedItem.name.empty()) {
             return S_FALSE;
         }
 
-        firstItem = Environment::selectedItem;
+        firstItem = Environment::INSTANCE->selectedItem;
     } else {
         CheckHr(firstItem.ExtractItemAt(psiItemArray, 1));
     }
@@ -137,7 +140,7 @@ auto STDMETHODCALLTYPE CDiffSubCommand::GetTitle(__RPC__in_opt IShellItemArray *
 }
 
 auto CDiffSubCommand::GetIcon(__RPC__in_opt IShellItemArray *psiItemArray, __RPC__deref_out_opt_string LPWSTR *ppszIcon) -> HRESULT {
-    return SHStrDupW((Environment::comparerPath + L",0").c_str(), ppszIcon);
+    return SHStrDupW((Environment::INSTANCE->comparerPath + L",0").c_str(), ppszIcon);
 }
 
 auto STDMETHODCALLTYPE CDiffSubCommand::GetState(__RPC__in_opt IShellItemArray *psiItemArray, BOOL fOkToBeSlow, __RPC__out EXPCMDSTATE *pCmdState) -> HRESULT {
@@ -169,21 +172,21 @@ auto STDMETHODCALLTYPE CDiffSubCommand::Invoke(__RPC__in_opt IShellItemArray *ps
         return E_UNEXPECTED;
     }
 
-    std::wstring cmdline = Environment::comparerArgs;
-    ReplaceSubString(cmdline, Environment::COMPARER_ARGS_LEFT_PLACEHOLDER, Environment::QuotePath(firstItem.name.c_str()));
-    ReplaceSubString(cmdline, Environment::COMPARER_ARGS_RIGHT_PLACEHOLDER, Environment::QuotePath(secondItem.name.c_str()));
+    std::wstring cmdline = Environment::INSTANCE->comparerArgs;
+    ReplaceSubString(cmdline, COMPARER_ARGS_LEFT_PLACEHOLDER, Environment::INSTANCE->QuotePath(firstItem.name.c_str()));
+    ReplaceSubString(cmdline, COMPARER_ARGS_RIGHT_PLACEHOLDER, Environment::INSTANCE->QuotePath(secondItem.name.c_str()));
 
     cmdline.insert(0, L" ");
-    cmdline.insert(0, Environment::comparerPath);
+    cmdline.insert(0, Environment::INSTANCE->comparerPath);
 
     STARTUPINFOW si = { .cb = sizeof(si) };
     PROCESS_INFORMATION pi;
     if (CreateProcessW(nullptr, cmdline.data(), nullptr, nullptr, FALSE, 0, nullptr, nullptr, &si, &pi)) {
         CloseHandle(pi.hThread);
         CloseHandle(pi.hProcess);
 
-        Environment::selectedItem.name.clear();
-        Environment::FlushSelectedItem();
+        Environment::INSTANCE->selectedItem.name.clear();
+        Environment::INSTANCE->FlushSelectedItem();
 
         return S_OK;
     }