zircon/tools/abigen/vdso_wrapper_generator.h

// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef ZIRCON_TOOLS_ABIGEN_VDSO_WRAPPER_GENERATOR_H_
#define ZIRCON_TOOLS_ABIGEN_VDSO_WRAPPER_GENERATOR_H_

#include "generator.h"

// Generates wrappers in the vDSO that add behavior defined by the given
// CallWrapper list.
class VdsoWrapperGenerator : public Generator {
 public:
  VdsoWrapperGenerator(std::string wrapper_prefix, std::string call_prefix,
                       std::vector<CallWrapper*> call_wrappers)
      : wrapper_prefix_(wrapper_prefix), call_prefix_(call_prefix), wrappers_(call_wrappers) {}

  bool syscall(std::ofstream& os, const Syscall& sc) override;

 private:
  void pre_call(std::ofstream& os, const Syscall& sc) const;
  void post_call(std::ofstream& os, const Syscall& sc, std::string return_var) const;

  std::string wrapper_prefix_;
  std::string call_prefix_;
  std::vector<CallWrapper*> wrappers_;
};

// Wrapper for testing that wrappers work correctly. Applied only to syscall_test_wrapper.
class TestWrapper : public CallWrapper {
 public:
  bool applies(const Syscall& sc) const override;
  // Adds a precondition that all args are > 0;
  void preCall(std::ofstream& os, const Syscall& sc) const override;
  // Adds a postcondition that the result is < 50;
  void postCall(std::ofstream& os, const Syscall& sc, std::string return_var) const override;
};

// Wraps a syscall with the "blocking" attribute with code that will
// automatically retry if interrupted.
class BlockingRetryWrapper : public CallWrapper {
 public:
  bool applies(const Syscall& sc) const override;
  void preCall(std::ofstream& os, const Syscall& sc) const override;
  void postCall(std::ofstream& os, const Syscall& sc, std::string return_var) const override;
};

#endif  // ZIRCON_TOOLS_ABIGEN_VDSO_WRAPPER_GENERATOR_H_