Files
clang-p2996/lldb/source/Plugins/ObjectContainer/BSD-Archive/ObjectContainerBSDArchive.h
Greg Clayton d4a141ef93 Switch over to using the LLVM archive parser for BSD archives.
Our LLDB parser didn't correctly handle archives of all flavors on different systems, it currently only correctly handled BSD archives, normal and thin, on macOS, but I noticed that it was getting incorrect information when decoding a variety of archives on linux. There were subtle changes to how names were encoded that we didn't handle correctly and we also didn't set the result of GetObjectSize() correctly as there was some bad math. This didn't matter when exracting .o files from .a files for LLDB because the size was always way too big, but it was big enough to at least read enough bytes for each object within the archive.

This patch does the following:
- switch over to use LLVM's archive parser and avoids previous code duplication
- remove values from ObjectContainerBSDArchive::Object that we don't use like:
  - uid
  - gid
  - mode
- fix ths ObjectContainerBSDArchive::Object::file_size value to be correct
- adds tests to test that we get the correct module specifications

Differential Revision: https://reviews.llvm.org/D159408
2023-09-05 16:54:05 -07:00

183 lines
6.1 KiB
C++

//===-- 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/FileSpec.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 &data);
// 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 &data,
lldb::offset_t offset,
llvm::StringRef stringTable);
lldb::offset_t Extract(const lldb_private::DataExtractor &data,
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_private::DataExtractor &data, 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_private::DataExtractor &data, 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_data; }
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;
lldb_private::DataExtractor m_data; ///< The data for this object container
///so we don't lose data if the .a files
///gets modified
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