system/Clock, fs/FileInfo: move FILETIME specific code to time/FileTime.hxx

src/fs/FileInfo.hxx

@@ -24,7 +24,7 @@
 #include "system/Error.hxx"
 
 #ifdef _WIN32
-#include <fileapi.h>
+#include "time/FileTime.hxx"
 #else
 #include <sys/stat.h>
 #endif
@@ -33,30 +33,6 @@
 
 #include <stdint.h>
 
-#ifdef _WIN32
-
-static constexpr uint64_t
-ConstructUint64(DWORD lo, DWORD hi)
-{
-	return uint64_t(lo) | (uint64_t(hi) << 32);
-}
-
-static constexpr time_t
-FileTimeToTimeT(FILETIME ft)
-{
-	return (ConstructUint64(ft.dwLowDateTime, ft.dwHighDateTime)
-		- 116444736000000000) / 10000000;
-}
-
-static std::chrono::system_clock::time_point
-FileTimeToChrono(FILETIME ft)
-{
-	// TODO: eliminate the time_t roundtrip, preserve sub-second resolution
-	return std::chrono::system_clock::from_time_t(FileTimeToTimeT(ft));
-}
-
-#endif
-
 class FileInfo {
 	friend bool GetFileInfo(Path path, FileInfo &info,
 				bool follow_symlinks);