Support: Add PathV2 implementation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120329 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Windows/PathV2.inc b/lib/Support/Windows/PathV2.inc
new file mode 100644
index 0000000..9c15e26
--- /dev/null
+++ b/lib/Support/Windows/PathV2.inc
@@ -0,0 +1,71 @@
+//===- llvm/Support/Win32/PathV2.cpp - Windows Path Impl --------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the Windows specific implementation of the PathV2 API.
+//
+//===----------------------------------------------------------------------===//
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only generic Windows code that
+//=== is guaranteed to work on *all* Windows variants.
+//===----------------------------------------------------------------------===//
+
+#include "Windows.h"
+
+namespace llvm {
+namespace sys {
+namespace path {
+
+error_code current_path(SmallVectorImpl<char> &result) {
+ SmallVector<wchar_t, 128> cur_path;
+ cur_path.reserve(128);
+retry_cur_dir:
+ DWORD len = ::GetCurrentDirectoryW(cur_path.capacity(), cur_path.data());
+
+ // A zero return value indicates a failure other than insufficient space.
+ if (len == 0)
+ return make_error_code(windows_error(::GetLastError()));
+
+ // If there's insufficient space, the len returned is larger than the len
+ // given.
+ if (len > cur_path.capacity()) {
+ cur_path.reserve(len);
+ goto retry_cur_dir;
+ }
+
+ cur_path.set_size(len);
+ // cur_path now holds the current directory in utf-16. Convert to utf-8.
+
+ // Find out how much space we need. Sadly, this function doesn't return the
+ // size needed unless you tell it the result size is 0, which means you
+ // _always_ have to call it twice.
+ len = ::WideCharToMultiByte(CP_UTF8, NULL,
+ cur_path.data(), cur_path.size(),
+ result.data(), 0,
+ NULL, NULL);
+
+ if (len == 0)
+ return make_error_code(windows_error(::GetLastError()));
+
+ result.reserve(len);
+ result.set_size(len);
+ // Now do the actual conversion.
+ len = ::WideCharToMultiByte(CP_UTF8, NULL,
+ cur_path.data(), cur_path.size(),
+ result.data(), result.size(),
+ NULL, NULL);
+ if (len == 0)
+ return make_error_code(windows_error(::GetLastError()));
+
+ return make_error_code(errc::success);
+}
+
+} // end namespace path
+} // end namespace sys
+} // end namespace llvm