File Explorer

1// Copyright 2020 the V8 project authors. All rights reserved.2// Use of this source code is governed by a BSD-style license that can be3// found in the LICENSE file.4 5#ifndef INCLUDE_CPPGC_NAME_PROVIDER_H_6#define INCLUDE_CPPGC_NAME_PROVIDER_H_7 8#include "v8config.h"  // NOLINT(build/include_directory)9 10namespace cppgc {11 12/**13 * NameProvider allows for providing a human-readable name for garbage-collected14 * objects.15 *16 * There's two cases of names to distinguish:17 * a. Explicitly specified names via using NameProvider. Such names are always18 *    preserved in the system.19 * b. Internal names that Oilpan infers from a C++ type on the class hierarchy20 *    of the object. This is not necessarily the type of the actually21 *    instantiated object.22 *23 * Depending on the build configuration, Oilpan may hide names, i.e., represent24 * them with kHiddenName, of case b. to avoid exposing internal details.25 */26class V8_EXPORT NameProvider {27 public:28  /**29   * Name that is used when hiding internals.30   */31  static constexpr const char kHiddenName[] = "InternalNode";32 33  /**34   * Name that is used in case compiler support is missing for composing a name35   * from C++ types.36   */37  static constexpr const char kNoNameDeducible[] = "<No name>";38 39  /**40   * Indicating whether the build supports extracting C++ names as object names.41   *42   * @returns true if C++ names should be hidden and represented by kHiddenName.43   */44  static constexpr bool SupportsCppClassNamesAsObjectNames() {45#if CPPGC_SUPPORTS_OBJECT_NAMES46    return true;47#else   // !CPPGC_SUPPORTS_OBJECT_NAMES48    return false;49#endif  // !CPPGC_SUPPORTS_OBJECT_NAMES50  }51 52  virtual ~NameProvider() = default;53 54  /**55   * Specifies a name for the garbage-collected object. Such names will never56   * be hidden, as they are explicitly specified by the user of this API.57   *58   * Implementations of this function must not allocate garbage-collected59   * objects or otherwise modify the cppgc heap.60   *61   * V8 may call this function while generating a heap snapshot or at other62   * times. If V8 is currently generating a heap snapshot (according to63   * HeapProfiler::IsTakingSnapshot), then the returned string must stay alive64   * until the snapshot generation has completed. Otherwise, the returned string65   * must stay alive forever. If you need a place to store a temporary string66   * during snapshot generation, use HeapProfiler::CopyNameForHeapSnapshot.67   *68   * @returns a human readable name for the object.69   */70  virtual const char* GetHumanReadableName() const = 0;71};72 73}  // namespace cppgc74 75#endif  // INCLUDE_CPPGC_NAME_PROVIDER_H_76