Rewrite vfs::get and vfs::mount

Preprocess . and .. correctly
Don't use recursive locking
Also use std::string_view
Fix format system for std::string and std::string_view
Fix fmt::merge for std::string_view

Utilities/File.cpp

@@ -513,6 +513,13 @@ bool fs::create_path(const std::string& path)
 
 bool fs::remove_dir(const std::string& path)
 {
+	if (path.empty())
+	{
+		// Don't allow removing empty path (TODO)
+		g_tls_error = fs::error::noent;
+		return false;
+	}
+
 	if (auto device = get_virtual_device(path))
 	{
 		return device->remove_dir(path);
@@ -539,6 +546,13 @@ bool fs::remove_dir(const std::string& path)
 
 bool fs::rename(const std::string& from, const std::string& to, bool overwrite)
 {
+	if (from.empty() || to.empty())
+	{
+		// Don't allow opening empty path (TODO)
+		g_tls_error = fs::error::noent;
+		return false;
+	}
+
 	const auto device = get_virtual_device(from);
 
 	if (device != get_virtual_device(to))
@@ -786,6 +800,13 @@ void fs::file::xfail() const
 
 fs::file::file(const std::string& path, bs_t<open_mode> mode)
 {
+	if (path.empty())
+	{
+		// Don't allow opening empty path (TODO)
+		g_tls_error = fs::error::noent;
+		return;
+	}
+
 	if (auto device = get_virtual_device(path))
 	{
 		if (auto&& _file = device->open(path, mode))
@@ -1176,6 +1197,13 @@ void fs::dir::xnull() const
 
 bool fs::dir::open(const std::string& path)
 {
+	if (path.empty())
+	{
+		// Don't allow opening empty path (TODO)
+		g_tls_error = fs::error::noent;
+		return false;
+	}
+
 	if (auto device = get_virtual_device(path))
 	{
 		if (auto&& _dir = device->open_dir(path))

Utilities/StrFmt.cpp

@@ -4,6 +4,7 @@
 #include "cfmt.h"
 
 #include <algorithm>
+#include <string_view>
 
 #ifdef _WIN32
 #include <Windows.h>
@@ -73,32 +74,31 @@ void fmt_class_string<fmt::base57>::format(std::string& out, u64 arg)
 
 void fmt_class_string<const void*>::format(std::string& out, u64 arg)
 {
-	if (arg)
-	{
-		fmt::append(out, "%p", reinterpret_cast<const void*>(static_cast<std::uintptr_t>(arg)));
-	}
-	else
-	{
-		out += "(NULL)";
-	}
+	fmt::append(out, "%p", arg);
 }
 
 void fmt_class_string<const char*>::format(std::string& out, u64 arg)
 {
 	if (arg)
 	{
-		out += reinterpret_cast<const char*>(static_cast<std::uintptr_t>(arg));
+		out += reinterpret_cast<const char*>(arg);
 	}
 	else
 	{
-		out += "(NULL)";
+		out += "(NULLSTR)";
 	}
 }
 
 template <>
 void fmt_class_string<std::string>::format(std::string& out, u64 arg)
 {
-	out += get_object(arg).c_str(); // TODO?
+	out += get_object(arg);
+}
+
+template <>
+void fmt_class_string<std::string_view>::format(std::string& out, u64 arg)
+{
+	out += get_object(arg);
 }
 
 template <>

Utilities/StrUtil.h

@@ -5,6 +5,7 @@
 #include <string>
 #include <vector>
 #include <functional>
+#include <string_view>
 
 // Copy null-terminated string from std::string to char array with truncation
 template <std::size_t N>
@@ -100,10 +101,10 @@ namespace fmt
 		auto end = source.end();
 		for (--end; it != end; ++it)
 		{
-			result += *it + separator;
+			result += std::string{*it} + separator;
 		}
 
-		return result + source.back();
+		return result + std::string{source.back()};
 	}
 
 	template <typename T>