Implement fs::get_cache_dir

Win32: equal to config dir for now
Linux: respect XDG_CACHE_HOME if specified
OSX: possibly incomplete

Utilities/File.cpp

@@ -1403,8 +1403,8 @@ const std::string& fs::get_config_dir()
 		if (const char* home = ::getenv("HOME"))
 			dir = home + "/Library/Application Support"s;
 #else
-		if (const char* home = ::getenv("XDG_CONFIG_HOME"))
-			dir = home;
+		if (const char* conf = ::getenv("XDG_CONFIG_HOME"))
+			dir = conf;
 		else if (const char* home = ::getenv("HOME"))
 			dir = home + "/.config"s;
 #endif
@@ -1425,15 +1425,53 @@ const std::string& fs::get_config_dir()
 	return s_dir;
 }
 
+const std::string& fs::get_cache_dir()
+{
+	static const std::string s_dir = []
+	{
+		std::string dir;
+
+#ifdef _WIN32
+		dir = get_config_dir();
+#else
+
+#ifdef __APPLE__
+		if (const char* home = ::getenv("HOME"))
+			dir = home + "/Library/Caches"s;
+#else
+		if (const char* cache = ::getenv("XDG_CACHE_HOME"))
+			dir = cache;
+		else if (const char* conf = ::getenv("XDG_CONFIG_HOME"))
+			dir = conf;
+		else if (const char* home = ::getenv("HOME"))
+			dir = home + "/.cache"s;
+#endif
+		else // Just in case
+			dir = "./cache";
+
+		dir += "/rpcs3/";
+
+		if (!create_path(dir))
+		{
+			std::printf("Failed to create configuration directory '%s' (%d).\n", dir.c_str(), errno);
+		}
+#endif
+
+		return dir;
+	}();
+
+	return s_dir;
+}
+
 std::string fs::get_data_dir(const std::string& prefix, const std::string& location, const std::string& suffix)
 {
 	static const std::string s_dir = []
 	{
-		const std::string dir = get_config_dir() + "data/";
+		const std::string dir = get_cache_dir() + "data/";
 
 		if (!create_path(dir))
 		{
-			return get_config_dir();
+			return get_cache_dir();
 		}
 
 		return dir;

Utilities/File.h

@@ -484,6 +484,9 @@ namespace fs
 	// Get configuration directory
 	const std::string& get_config_dir();
 
+	// Get common cache directory
+	const std::string& get_cache_dir();
+
 	// Get data/cache directory for specified prefix and suffix
 	std::string get_data_dir(const std::string& prefix, const std::string& location, const std::string& suffix);
 

Utilities/Log.cpp

@@ -322,8 +322,8 @@ void logs::message::broadcast(const char* fmt, const fmt_type_info* sup, ...) co
 logs::file_writer::file_writer(const std::string& name)
 	: m_name(name)
 {
-	const std::string log_name = fs::get_config_dir() + name + ".log";
-	const std::string buf_name = fs::get_config_dir() + name + ".buf";
+	const std::string log_name = fs::get_cache_dir() + name + ".log";
+	const std::string buf_name = fs::get_cache_dir() + name + ".buf";
 
 	try
 	{
@@ -352,7 +352,7 @@ logs::file_writer::file_writer(const std::string& name)
 
 		// Check free space
 		fs::device_stat stats{};
-		if (!fs::statfs(fs::get_config_dir(), stats) || stats.avail_free < s_log_size * 8)
+		if (!fs::statfs(fs::get_cache_dir(), stats) || stats.avail_free < s_log_size * 8)
 		{
 			fmt::throw_exception("Not enough free space (%f KB)", stats.avail_free / 1000000.);
 		}
@@ -372,9 +372,9 @@ logs::file_writer::file_writer(const std::string& name)
 		verify(name.c_str()), m_fptr;
 
 		// Rotate backups (TODO)
-		fs::remove_file(fs::get_config_dir() + name + "1.log.gz");
-		fs::create_dir(fs::get_config_dir() + "old_logs");
-		fs::rename(fs::get_config_dir() + m_name + ".log.gz", fs::get_config_dir() + "old_logs/" + m_name + ".log.gz", true);
+		fs::remove_file(fs::get_cache_dir() + name + "1.log.gz");
+		fs::create_dir(fs::get_cache_dir() + "old_logs");
+		fs::rename(fs::get_cache_dir() + m_name + ".log.gz", fs::get_cache_dir() + "old_logs/" + m_name + ".log.gz", true);
 
 		// Actual log file (allowed to fail)
 		m_fout.open(log_name, fs::rewrite);