Implement relocatable builds on Linux

- Change the path of the Sys folder to the executable's location
- Add LINUX_LOCAL_DEV flag to use relocatable version on Linux
- Add CMake definition for relocatable build

CMakeLists.txt

@@ -312,6 +312,12 @@ if(WIN32)
 	add_definitions(-D_CRT_SECURE_NO_DEPRECATE)
 endif(WIN32)
 
+# Add an option to build relocatable binaries on Linux
+# The Sys folder will need to be copied to the Binaries folder.
+if(UNIX)
+	add_definitions(-DLINUX_LOCAL_DEV=0)
+endif(UNIX)
+
 # Dolphin requires threads.
 # The Apple build may not need an explicit flag because one of the
 # frameworks may already provide it.

Source/Core/Common/CommonPaths.h

@@ -32,7 +32,7 @@
 #endif
 
 // Shared data dirs (Sys and shared User for Linux)
-#ifdef _WIN32
+#if defined(_WIN32) || defined(LINUX_LOCAL_DEV)
 	#define SYSDATA_DIR "Sys"
 #elif defined __APPLE__
 	#define SYSDATA_DIR "Contents/Resources/Sys"

Source/Core/Common/FileUtil.cpp

@@ -728,12 +728,12 @@ std::string GetBundleDirectory()
 }
 #endif
 
-#ifdef _WIN32
 std::string& GetExeDirectory()
 {
 	static std::string DolphinPath;
 	if (DolphinPath.empty())
 	{
+#ifdef _WIN32
 		TCHAR Dolphin_exe_Path[2048];
 		TCHAR Dolphin_exe_Clean_Path[MAX_PATH];
 		GetModuleFileName(nullptr, Dolphin_exe_Path, 2048);
@@ -742,10 +742,20 @@ std::string& GetExeDirectory()
 		else
 			DolphinPath = TStrToUTF8(Dolphin_exe_Path);
 		DolphinPath = DolphinPath.substr(0, DolphinPath.find_last_of('\\'));
+#else
+		char Dolphin_exe_Path[PATH_MAX];
+		ssize_t len = ::readlink("/proc/self/exe", Dolphin_exe_Path, sizeof(Dolphin_exe_Path));
+		if (len == -1 || len == sizeof(Dolphin_exe_Path))
+		{
+			len = 0;
+		}
+		Dolphin_exe_Path[len] = '\0';
+		DolphinPath = Dolphin_exe_Path;
+		DolphinPath = DolphinPath.substr(0, DolphinPath.rfind('/'));
+#endif
 	}
 	return DolphinPath;
 }
-#endif
 
 std::string GetSysDirectory()
 {
@@ -753,7 +763,7 @@ std::string GetSysDirectory()
 
 #if defined (__APPLE__)
 	sysDir = GetBundleDirectory() + DIR_SEP + SYSDATA_DIR;
-#elif defined (_WIN32)
+#elif defined (_WIN32) || defined (LINUX_LOCAL_DEV)
 	sysDir = GetExeDirectory() + DIR_SEP + SYSDATA_DIR;
 #else
 	sysDir = SYSDATA_DIR;

Source/Core/Common/FileUtil.h

@@ -145,9 +145,7 @@ std::string GetSysDirectory();
 std::string GetBundleDirectory();
 #endif
 
-#ifdef _WIN32
 std::string &GetExeDirectory();
-#endif
 
 bool WriteStringToFile(const std::string& str, const std::string& filename);
 bool ReadFileToString(const std::string& filename, std::string& str);