ObjectContainerBSDArchive.h

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//===-- ObjectContainerBSDArchive.h -----------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
 
#ifndef LLDB_SOURCE_PLUGINS_OBJECTCONTAINER_BSD_ARCHIVE_OBJECTCONTAINERBSDARCHIVE_H
#define LLDB_SOURCE_PLUGINS_OBJECTCONTAINER_BSD_ARCHIVE_OBJECTCONTAINERBSDARCHIVE_H
 
#include "lldb/Core/UniqueCStringMap.h"
#include "lldb/Symbol/ObjectContainer.h"
#include "lldb/Utility/ArchSpec.h"
#include "lldb/Utility/ConstString.h"
#include "lldb/Utility/DataExtractor.h"
#include "lldb/Utility/FileSpec.h"
#include "lldb/Utility/NonNullSharedPtr.h"
 
#include "llvm/Object/Archive.h"
#include "llvm/Support/Chrono.h"
#include "llvm/Support/Path.h"
 
#include <map>
#include <memory>
#include <mutex>
 
enum class ArchiveType { Invalid, Archive, ThinArchive };
 
class ObjectContainerBSDArchive : public lldb_private::ObjectContainer {
public:
  ObjectContainerBSDArchive(const lldb::ModuleSP &module_sp,
                            lldb::DataBufferSP &data_sp,
                            lldb::offset_t data_offset,
                            const lldb_private::FileSpec *file,
                            lldb::offset_t offset, lldb::offset_t length,
                            ArchiveType archive_type);
 
  ~ObjectContainerBSDArchive() override;
 
  // Static Functions
  static void Initialize();
 
  static void Terminate();
 
  static llvm::StringRef GetPluginNameStatic() { return "bsd-archive"; }
 
  static llvm::StringRef GetPluginDescriptionStatic() {
    return "BSD Archive object container reader.";
  }
 
  static lldb_private::ObjectContainer *
  CreateInstance(const lldb::ModuleSP &module_sp, lldb::DataBufferSP &data_sp,
                 lldb::offset_t data_offset, const lldb_private::FileSpec *file,
                 lldb::offset_t offset, lldb::offset_t length);
 
  static size_t GetModuleSpecifications(const lldb_private::FileSpec &file,
                                        lldb::DataBufferSP &data_sp,
                                        lldb::offset_t data_offset,
                                        lldb::offset_t file_offset,
                                        lldb::offset_t length,
                                        lldb_private::ModuleSpecList &specs);
 
  static ArchiveType
  MagicBytesMatch(const lldb_private::DataExtractor &extractor);
 
  // Member Functions
  bool ParseHeader() override;
 
  size_t GetNumObjects() const override {
    if (m_archive_sp)
      return m_archive_sp->GetNumObjects();
    return 0;
  }
 
  lldb::ObjectFileSP GetObjectFile(const lldb_private::FileSpec *file) override;
 
  // PluginInterface protocol
  llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }
 
protected:
  struct Object {
    Object();
 
    void Clear();
 
    lldb::offset_t ExtractFromThin(const lldb_private::DataExtractor &extractor,
                                   lldb::offset_t offset,
                                   llvm::StringRef stringTable);
 
    lldb::offset_t Extract(const lldb_private::DataExtractor &extractor,
                           lldb::offset_t offset);
    /// Object name in the archive.
    lldb_private::ConstString ar_name;
 
    /// Object modification time in the archive.
    uint32_t modification_time = 0;
 
    /// Object size in bytes in the archive.
    uint32_t size = 0;
 
    /// File offset in bytes from the beginning of the file of the object data.
    lldb::offset_t file_offset = 0;
 
    /// Length of the object data.
    lldb::offset_t file_size = 0;
 
    void Dump() const;
  };
 
  class Archive {
  public:
    typedef std::shared_ptr<Archive> shared_ptr;
    typedef std::multimap<lldb_private::FileSpec, shared_ptr> Map;
 
    Archive(const lldb_private::ArchSpec &arch,
            const llvm::sys::TimePoint<> &mod_time, lldb::offset_t file_offset,
            lldb::DataExtractorSP extractor_sp, ArchiveType archive_type);
 
    ~Archive();
 
    static Map &GetArchiveCache();
 
    static std::recursive_mutex &GetArchiveCacheMutex();
 
    static Archive::shared_ptr FindCachedArchive(
        const lldb_private::FileSpec &file, const lldb_private::ArchSpec &arch,
        const llvm::sys::TimePoint<> &mod_time, lldb::offset_t file_offset);
 
    static Archive::shared_ptr ParseAndCacheArchiveForFile(
        const lldb_private::FileSpec &file, const lldb_private::ArchSpec &arch,
        const llvm::sys::TimePoint<> &mod_time, lldb::offset_t file_offset,
        lldb::DataExtractorSP extractor_sp, ArchiveType archive_type);
 
    size_t GetNumObjects() const { return m_objects.size(); }
 
    const Object *GetObjectAtIndex(size_t idx) {
      if (idx < m_objects.size())
        return &m_objects[idx];
      return nullptr;
    }
 
    size_t ParseObjects();
 
    Object *FindObject(lldb_private::ConstString object_name,
                       const llvm::sys::TimePoint<> &object_mod_time);
 
    lldb::offset_t GetFileOffset() const { return m_file_offset; }
 
    const llvm::sys::TimePoint<> &GetModificationTime() {
      return m_modification_time;
    }
 
    const lldb_private::ArchSpec &GetArchitecture() const { return m_arch; }
 
    void SetArchitecture(const lldb_private::ArchSpec &arch) { m_arch = arch; }
 
    bool HasNoExternalReferences() const;
 
    lldb_private::DataExtractor &GetData() { return *m_extractor_sp.get(); }
    lldb::DataExtractorSP &GetDataSP() { return m_extractor_sp; }
 
    ArchiveType GetArchiveType() { return m_archive_type; }
 
  protected:
    typedef lldb_private::UniqueCStringMap<uint32_t> ObjectNameToIndexMap;
    // Member Variables
    lldb_private::ArchSpec m_arch;
    llvm::sys::TimePoint<> m_modification_time;
    lldb::offset_t m_file_offset;
    std::vector<Object> m_objects;
    ObjectNameToIndexMap m_object_name_to_index_map;
    /// The data for this object container so we don't lose data if the .a files
    /// gets modified.
    lldb::DataExtractorSP m_extractor_sp;
    ArchiveType m_archive_type;
  };
 
  void SetArchive(Archive::shared_ptr &archive_sp);
 
  Archive::shared_ptr m_archive_sp;
 
  ArchiveType m_archive_type;
};
 
#endif // LLDB_SOURCE_PLUGINS_OBJECTCONTAINER_BSD_ARCHIVE_OBJECTCONTAINERBSDARCHIVE_H