Move GetModuleName to Common

This unifies GetModuleFileName calls between Dolphin and WinUpdater
and allows to gracefully remove MAX_PATH limit from GetExePath

Source/Core/Common/CommonFuncs.cpp

@@ -49,4 +49,27 @@ std::string GetLastErrorString()
                  MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), error_message, BUFFER_SIZE, nullptr);
   return std::string(error_message);
 }
+
+// Obtains a full path to the specified module.
+std::optional<std::wstring> GetModuleName(void* hInstance)
+{
+  DWORD max_size = 50;  // Start with space for 50 characters and grow if needed
+  std::wstring name(max_size, L'\0');
+
+  DWORD size;
+  while ((size = GetModuleFileNameW(static_cast<HMODULE>(hInstance), name.data(), max_size)) ==
+             max_size &&
+         GetLastError() == ERROR_INSUFFICIENT_BUFFER)
+  {
+    max_size *= 2;
+    name.resize(max_size);
+  }
+
+  if (size == 0)
+  {
+    return std::nullopt;
+  }
+  name.resize(size);
+  return name;
+}
 #endif

Source/Core/Common/CommonFuncs.h

@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include <optional>
 #include <string>
 #include "Common/CommonTypes.h"
 
@@ -47,4 +48,7 @@ std::string LastStrerrorString();
 // Wrapper function to get GetLastError() string.
 // This function might change the error code.
 std::string GetLastErrorString();
+
+// Obtains a full path to the specified module.
+std::optional<std::wstring> GetModuleName(void* hInstance);
 #endif

Source/Core/Common/CompatPatches.cpp

@@ -4,12 +4,14 @@
 
 #include <Windows.h>
 #include <functional>
+#include <optional>
 #include <string>
 #include <vector>
 #include <winternl.h>
 
 #include <fmt/format.h>
 
+#include "Common/CommonFuncs.h"
 #include "Common/CommonTypes.h"
 #include "Common/LdrWatcher.h"
 #include "Common/StringUtil.h"
@@ -162,37 +164,26 @@ struct Version
   }
 };
 
-static bool GetModulePath(const wchar_t* name, std::wstring* path)
+static std::optional<std::wstring> GetModulePath(const wchar_t* name)
 {
   auto module = GetModuleHandleW(name);
   if (module == nullptr)
-    return false;
-  DWORD path_len = MAX_PATH;
-retry:
-  path->resize(path_len);
-  path_len = GetModuleFileNameW(module, const_cast<wchar_t*>(path->data()),
-                                static_cast<DWORD>(path->size()));
-  if (!path_len)
-    return false;
-  auto error = GetLastError();
-  if (error == ERROR_SUCCESS)
-    return true;
-  if (error == ERROR_INSUFFICIENT_BUFFER)
-    goto retry;
-  return false;
+    return std::nullopt;
+
+  return GetModuleName(module);
 }
 
 static bool GetModuleVersion(const wchar_t* name, Version* version)
 {
-  std::wstring path;
-  if (!GetModulePath(name, &path))
+  auto path = GetModulePath(name);
+  if (!path)
     return false;
   DWORD handle;
-  DWORD data_len = GetFileVersionInfoSizeW(path.c_str(), &handle);
+  DWORD data_len = GetFileVersionInfoSizeW(path->c_str(), &handle);
   if (!data_len)
     return false;
   std::vector<u8> block(data_len);
-  if (!GetFileVersionInfoW(path.c_str(), handle, data_len, block.data()))
+  if (!GetFileVersionInfoW(path->c_str(), handle, data_len, block.data()))
     return false;
   void* buf;
   UINT buf_len;

Source/Core/Common/FileUtil.cpp

@@ -674,22 +674,26 @@ std::string GetBundleDirectory()
 
 std::string GetExePath()
 {
-  static std::string dolphin_path;
-  if (dolphin_path.empty())
-  {
+  static const std::string dolphin_path = [] {
+    std::string result;
 #ifdef _WIN32
-    TCHAR dolphin_exe_path[2048];
-    TCHAR dolphin_exe_expanded_path[MAX_PATH];
-    GetModuleFileName(nullptr, dolphin_exe_path, ARRAYSIZE(dolphin_exe_path));
-    if (_tfullpath(dolphin_exe_expanded_path, dolphin_exe_path,
-                   ARRAYSIZE(dolphin_exe_expanded_path)) != nullptr)
-      dolphin_path = TStrToUTF8(dolphin_exe_expanded_path);
+    auto dolphin_exe_path = GetModuleName(nullptr);
+    if (dolphin_exe_path)
+    {
+      std::unique_ptr<TCHAR[], decltype(&std::free)> dolphin_exe_expanded_path{
+          _tfullpath(nullptr, dolphin_exe_path->c_str(), 0), std::free};
+      if (dolphin_exe_expanded_path)
+      {
+        result = TStrToUTF8(dolphin_exe_expanded_path.get());
+      }
       else
-      dolphin_path = TStrToUTF8(dolphin_exe_path);
+      {
+        result = TStrToUTF8(*dolphin_exe_path);
+      }
+    }
 #elif defined(__APPLE__)
-    dolphin_path = GetBundleDirectory();
-    dolphin_path =
-        dolphin_path.substr(0, dolphin_path.find_last_of("Dolphin.app/Contents/MacOS") + 1);
+    result = GetBundleDirectory();
+    result = result.substr(0, result.find_last_of("Dolphin.app/Contents/MacOS") + 1);
 #else
     char dolphin_exe_path[PATH_MAX];
     ssize_t len = ::readlink("/proc/self/exe", dolphin_exe_path, sizeof(dolphin_exe_path));
@@ -698,9 +702,10 @@ std::string GetExePath()
       len = 0;
     }
     dolphin_exe_path[len] = '\0';
-    dolphin_path = dolphin_exe_path;
+    result = dolphin_exe_path;
 #endif
-  }
+    return result;
+  }();
   return dolphin_path;
 }
 

Source/Core/WinUpdater/Main.cpp

@@ -10,6 +10,7 @@
 #include <string>
 #include <vector>
 
+#include "Common/CommonFuncs.h"
 #include "Common/StringUtil.h"
 
 #include "UpdaterCommon/UI.h"
@@ -33,28 +34,6 @@ std::vector<std::string> CommandLineToUtf8Argv(PCWSTR command_line)
   LocalFree(tokenized);
   return argv;
 }
-
-std::optional<std::wstring> GetModuleName(HINSTANCE hInstance)
-{
-  std::wstring name;
-  DWORD max_size = 50;  // Start with space for 50 characters and grow if needed
-  name.resize(max_size);
-
-  DWORD size;
-  while ((size = GetModuleFileNameW(hInstance, name.data(), max_size)) == max_size &&
-         GetLastError() == ERROR_INSUFFICIENT_BUFFER)
-  {
-    max_size *= 2;
-    name.resize(max_size);
-  }
-
-  if (size == 0)
-  {
-    return {};
-  }
-  name.resize(size);
-  return name;
-}
 };  // namespace
 
 int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine, int nCmdShow)