Refactor DependencyScanningTool to its own file

Summary:
There's no behavior change - just moving DependencyScanningTool to its own file
since this tool can be reused across both clang-scan-deps binary and an interface
exposed as part of libClang APIs.

Reviewers: arphaman, jkorous, Bigcheese, dexonsmith

Subscribers: mgorny, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D69186

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@375483 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 48 insertions, 0 deletions

diff --git a/include/clang/Tooling/DependencyScanning/DependencyScanningTool.h b/include/clang/Tooling/DependencyScanning/DependencyScanningTool.h
new file mode 100644
index 0000000000..0c9efccb1d
--- /dev/null
+++ b/include/clang/Tooling/DependencyScanning/DependencyScanningTool.h
@@ -0,0 +1,48 @@
+//===- DependencyScanningTool.h - clang-scan-deps service ------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLING_DEPENDENCY_SCANNING_TOOL_H
+#define LLVM_CLANG_TOOLING_DEPENDENCY_SCANNING_TOOL_H
+
+#include "clang/Tooling/DependencyScanning/DependencyScanningService.h"
+#include "clang/Tooling/DependencyScanning/DependencyScanningWorker.h"
+#include "clang/Tooling/JSONCompilationDatabase.h"
+#include <string>
+
+namespace clang{
+namespace tooling{
+namespace dependencies{
+
+/// The high-level implementation of the dependency discovery tool that runs on
+/// an individual worker thread.
+class DependencyScanningTool {
+public:
+  /// Construct a dependency scanning tool.
+  ///
+  /// \param Compilations     The reference to the compilation database that's
+  /// used by the clang tool.
+  DependencyScanningTool(DependencyScanningService &Service, const clang::tooling::CompilationDatabase &Compilations);
+
+  /// Print out the dependency information into a string using the dependency
+  /// file format that is specified in the options (-MD is the default) and
+  /// return it.
+  ///
+  /// \returns A \c StringError with the diagnostic output if clang errors
+  /// occurred, dependency file contents otherwise.
+  llvm::Expected<std::string> getDependencyFile(const std::string &Input, StringRef CWD);
+
+private:
+  DependencyScanningWorker Worker;
+  const tooling::CompilationDatabase &Compilations;
+};
+
+} // end namespace dependencies
+} // end namespace tooling
+} // end namespace clang
+
+#endif // LLVM_CLANG_TOOLING_DEPENDENCY_SCANNING_TOOL_H