add external dependencies in a pre-built way to avoid incompatibilities

external/include/google/protobuf/compiler/csharp/csharp_generator.h

@@ -0,0 +1,70 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Generates C# code for a given .proto file.
+
+#ifndef GOOGLE_PROTOBUF_COMPILER_CSHARP_GENERATOR_H__
+#define GOOGLE_PROTOBUF_COMPILER_CSHARP_GENERATOR_H__
+
+#include <string>
+
+#include <google/protobuf/compiler/code_generator.h>
+
+#include <google/protobuf/port_def.inc>
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace csharp {
+
+// CodeGenerator implementation which generates a C# source file and
+// header.  If you create your own protocol compiler binary and you want
+// it to support C# output, you can do so by registering an instance of this
+// CodeGenerator with the CommandLineInterface in your main() function.
+class PROTOC_EXPORT Generator : public CodeGenerator {
+ public:
+  Generator();
+  ~Generator();
+  bool Generate(
+    const FileDescriptor* file,
+    const std::string& parameter,
+    GeneratorContext* generator_context,
+    std::string* error) const override;
+  uint64_t GetSupportedFeatures() const override;
+};
+
+}  // namespace csharp
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#include <google/protobuf/port_undef.inc>
+
+#endif  // GOOGLE_PROTOBUF_COMPILER_CSHARP_GENERATOR_H__