1 files changed, 44 insertions, 0 deletions
diff --git a/lib/Driver/DarwinSDKInfo.cpp b/lib/Driver/DarwinSDKInfo.cpp
new file mode 100644
index 0000000000..547978b2f9
--- /dev/null
+++ b/lib/Driver/DarwinSDKInfo.cpp
@@ -0,0 +1,44 @@
+//===--- DarwinSDKInfo.cpp - SDK Information parser for darwin - ----------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Driver/DarwinSDKInfo.h"
+#include "llvm/Support/ErrorOr.h"
+#include "llvm/Support/JSON.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Path.h"
+
+using namespace clang::driver;
+using namespace clang;
+
+Expected<Optional<DarwinSDKInfo>>
+driver::parseDarwinSDKInfo(llvm::vfs::FileSystem &VFS, StringRef SDKRootPath) {
+  llvm::SmallString<256> Filepath = SDKRootPath;
+  llvm::sys::path::append(Filepath, "SDKSettings.json");
+  llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> File =
+      VFS.getBufferForFile(Filepath);
+  if (!File) {
+    // If the file couldn't be read, assume it just doesn't exist.
+    return None;
+  }
+  Expected<llvm::json::Value> Result =
+      llvm::json::parse(File.get()->getBuffer());
+  if (!Result)
+    return Result.takeError();
+
+  if (const auto *Obj = Result->getAsObject()) {
+    auto VersionString = Obj->getString("Version");
+    if (VersionString) {
+      VersionTuple Version;
+      if (!Version.tryParse(*VersionString))
+        return DarwinSDKInfo(Version);
+    }
+  }
+  return llvm::make_error<llvm::StringError>("invalid SDKSettings.json",
+                                             llvm::inconvertibleErrorCode());
+}