interceptor_utils.cc

/*
 * Copyright (C) 2021 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "interceptor_utils.h"

#include <iomanip>
#include <iterator>
#include <sstream>

#include <android-base/strings.h>

#include "interceptor.h"

namespace interceptor {

template <typename C>
struct PrintableSequence {
  PrintableSequence(const C& c) : container(c) {}
  const C& container;
};

template <typename C>
static std::ostream& operator<<(std::ostream& os, const PrintableSequence<C>& sequence) {
  bool comma = false;
  for (const auto& e : sequence.container) {
    if (comma) {
      os << ", ";
    }
    os << std::quoted(e);
    comma = true;
  }
  return os;
}

std::ostream& operator<<(std::ostream& os, const interceptor::Command& command) {
  os << "[(" << PrintableSequence(command.inputs()) << ") => ("
     << PrintableSequence(command.outputs()) << ")] " << command_line(command);
  return os;
}

std::string command_line(const Command& command) {
  // TODO: chain output iterators instead and find a common expression
  const static auto escape = [](auto in) {
    in = android::base::StringReplace(in, "\t", "\\t", true);
    in = android::base::StringReplace(in, "\n", "\\n", true);
    return in;
  };

  std::ostringstream cmd;
  cmd << command.program();
  for (auto iter = std::next(command.arguments().cbegin()); iter != command.arguments().cend();
       ++iter) {
    cmd << ' ' << escape(*iter);
  }
  return cmd.str();
}

}  // namespace interceptor