From d0e171784ce78f191a9bcb40857fc2656a1079d8 Mon Sep 17 00:00:00 2001
From: Nekotekina <nekotekina@gmail.com>
Date: Tue, 22 Aug 2017 21:05:51 +0300
Subject: [PATCH] Implemented fs::file::get_handle

---
 Utilities/File.cpp | 28 ++++++++++++++++++++++++++--
 Utilities/File.h   | 15 +++++++++++++++
 2 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/Utilities/File.cpp b/Utilities/File.cpp
index 4abdd90c36..225c7d4547 100644
--- a/Utilities/File.cpp
+++ b/Utilities/File.cpp
@@ -772,7 +772,7 @@ fs::file::file(const std::string& path, bs_t<open_mode> mode)
 		return;
 	}
 
-	class windows_file final : public file_base
+	class windows_file final : public file_base, public get_native_handle
 	{
 		const HANDLE m_handle;
 
@@ -879,6 +879,11 @@ fs::file::file(const std::string& path, bs_t<open_mode> mode)
 
 			return size.QuadPart;
 		}
+
+		native_handle get() override
+		{
+			return m_handle;
+		}
 	};
 
 	m_file = std::make_unique<windows_file>(handle);
@@ -902,7 +907,7 @@ fs::file::file(const std::string& path, bs_t<open_mode> mode)
 		return;
 	}
 
-	class unix_file final : public file_base
+	class unix_file final : public file_base, public get_native_handle
 	{
 		const int m_fd;
 
@@ -991,6 +996,11 @@ fs::file::file(const std::string& path, bs_t<open_mode> mode)
 
 			return file_info.st_size;
 		}
+
+		native_handle get() override
+		{
+			return m_fd;
+		}
 	};
 
 	m_file = std::make_unique<unix_file>(fd);
@@ -1066,6 +1076,20 @@ fs::file::file(const void* ptr, std::size_t size)
 	m_file = std::make_unique<memory_stream>(ptr, size);
 }
 
+fs::native_handle fs::file::get_handle() const
+{
+	if (auto getter = dynamic_cast<get_native_handle*>(m_file.get()))
+	{
+		return getter->get();
+	}
+
+#ifdef _WIN32
+	return INVALID_HANDLE_VALUE;
+#else
+	return -1;
+#endif
+}
+
 void fs::dir::xnull() const
 {
 	fmt::throw_exception<std::logic_error>("fs::dir is null");
diff --git a/Utilities/File.h b/Utilities/File.h
index 8c99fc11ce..9293410461 100644
--- a/Utilities/File.h
+++ b/Utilities/File.h
@@ -10,6 +10,12 @@
 
 namespace fs
 {
+#ifdef _WIN32
+	using native_handle = void*;
+#else
+	using native_handle = int;
+#endif
+
 	// File open mode flags
 	enum class open_mode : u32
 	{
@@ -55,6 +61,12 @@ namespace fs
 		s64 ctime;
 	};
 
+	// Native handle getter
+	struct get_native_handle
+	{
+		virtual native_handle get() = 0;
+	};
+
 	// File handle base
 	struct file_base
 	{
@@ -347,6 +359,9 @@ namespace fs
 			if (seek(0), !read(result)) xfail();
 			return result;
 		}
+
+		// Get native handle if available
+		native_handle get_handle() const;
 	};
 
 	class dir final