Method CleanMetaData

Source/cmGlobalNinjaGenerator.cxx:673–741

}

void cmGlobalNinjaGenerator::CleanMetaData()
{
  constexpr size_t ninja_tool_arg_size = 8; // 2 `-_` flags and 4 separators
  auto run_ninja_tool = [this](std::vector<char const*> const& args) {
    std::vector<std::string> command;
    command.push_back(this->NinjaCommand);
    command.emplace_back("-C");
    command.emplace_back(this->GetCMakeInstance()->GetHomeOutputDirectory());
    command.emplace_back("-t");
    for (auto const& arg : args) {
      command.emplace_back(arg);
    }
    std::string error;
    if (!cmSystemTools::RunSingleCommand(command, nullptr, &error, nullptr,
                                         nullptr,
                                         cmSystemTools::OUTPUT_NONE)) {
      this->GetCMakeInstance()->IssueMessage(MessageType::FATAL_ERROR,
                                             cmStrCat("Running\n '",
                                                      cmJoin(command, "' '"),
                                                      "'\n"
                                                      "failed with:\n ",
                                                      error));
      cmSystemTools::SetFatalErrorOccurred();
    }
  };

  // Can the tools below expect 'build.ninja' to be loadable?
  bool const expectBuildManifest =
    !this->IsMultiConfig() && this->OutputPathPrefix.empty();

  // Skip some ninja tools if they need 'build.ninja' but it is missing.
  bool const missingBuildManifest = expectBuildManifest &&
    this->NinjaSupportsUnconditionalRecompactTool &&
    !cmSystemTools::FileExists("build.ninja");

  // The `recompact` tool loads the manifest. As above, we don't have a single
  // `build.ninja` to load for this in Ninja-Multi. This may be relaxed in the
  // future pending further investigation into how Ninja works upstream
  // (ninja#1721).
  if (this->NinjaSupportsUnconditionalRecompactTool &&
      !this->GetCMakeInstance()->GetRegenerateDuringBuild() &&
      expectBuildManifest && !missingBuildManifest) {
    run_ninja_tool({ "recompact" });
  }
  if (this->NinjaSupportsRestatTool && this->OutputPathPrefix.empty()) {
    cmNinjaDeps outputs;
    this->AddRebuildManifestOutputs(outputs);
    auto output_it = outputs.begin();
    size_t static_arg_size = ninja_tool_arg_size + this->NinjaCommand.size() +
      this->GetCMakeInstance()->GetHomeOutputDirectory().size();
    // The Windows command-line length limit is 32768, but if `ninja` is
    // wrapped by a `.bat` file, the limit is 8192.  Leave plenty.
    constexpr size_t maximum_arg_size = 8000;
    while (output_it != outputs.end()) {
      size_t total_arg_size = static_arg_size;
      std::vector<char const*> args;
      args.reserve(std::distance(output_it, outputs.end()) + 1);
      args.push_back("restat");