[Support] Add a function to check if a file resides locally.
Differential Revision: https://reviews.llvm.org/D30010
llvm-svn: 295768
diff --git a/llvm/lib/Support/Windows/Path.inc b/llvm/lib/Support/Windows/Path.inc
index 3597b55..d9e1ff4 100644
--- a/llvm/lib/Support/Windows/Path.inc
+++ b/llvm/lib/Support/Windows/Path.inc
@@ -277,6 +277,80 @@
return std::error_code();
}
+static std::error_code is_local_internal(SmallVectorImpl<wchar_t> &Path,
+ bool &Result) {
+ SmallVector<wchar_t, 128> VolumePath;
+ size_t Len = 128;
+ while (true) {
+ VolumePath.resize(Len);
+ BOOL Success =
+ ::GetVolumePathNameW(Path.data(), VolumePath.data(), VolumePath.size());
+
+ if (Success)
+ break;
+
+ DWORD Err = ::GetLastError();
+ if (Err != ERROR_INSUFFICIENT_BUFFER)
+ return mapWindowsError(Err);
+
+ Len *= 2;
+ }
+ // If the output buffer has exactly enough space for the path name, but not
+ // the null terminator, it will leave the output unterminated. Push a null
+ // terminator onto the end to ensure that this never happens.
+ VolumePath.push_back(L'\0');
+ VolumePath.set_size(wcslen(VolumePath.data()));
+ const wchar_t *P = VolumePath.data();
+
+ UINT Type = ::GetDriveTypeW(P);
+ switch (Type) {
+ case DRIVE_FIXED:
+ Result = true;
+ return std::error_code();
+ case DRIVE_REMOTE:
+ case DRIVE_CDROM:
+ case DRIVE_RAMDISK:
+ case DRIVE_REMOVABLE:
+ Result = false;
+ return std::error_code();
+ default:
+ return make_error_code(errc::no_such_file_or_directory);
+ }
+ llvm_unreachable("Unreachable!");
+}
+
+std::error_code is_local(const Twine &path, bool &result) {
+ if (!llvm::sys::fs::exists(path) || !llvm::sys::path::has_root_path(path))
+ return make_error_code(errc::no_such_file_or_directory);
+
+ SmallString<128> Storage;
+ StringRef P = path.toStringRef(Storage);
+
+ // Convert to utf-16.
+ SmallVector<wchar_t, 128> WidePath;
+ if (std::error_code ec = widenPath(P, WidePath))
+ return ec;
+ return is_local_internal(WidePath, result);
+}
+
+std::error_code is_local(int FD, bool &Result) {
+ SmallVector<wchar_t, 128> FinalPath;
+ HANDLE Handle = reinterpret_cast<HANDLE>(_get_osfhandle(FD));
+
+ size_t Len = 128;
+ do {
+ FinalPath.reserve(Len);
+ Len = ::GetFinalPathNameByHandleW(Handle, FinalPath.data(),
+ FinalPath.capacity() - 1, VOLUME_NAME_NT);
+ if (Len == 0)
+ return mapWindowsError(::GetLastError());
+ } while (Len > FinalPath.capacity());
+
+ FinalPath.set_size(Len);
+
+ return is_local_internal(FinalPath, Result);
+}
+
std::error_code rename(const Twine &from, const Twine &to) {
// Convert to utf-16.
SmallVector<wchar_t, 128> wide_from;