blob: b202898ff438a6352b01d742b13980f4c67252bf [file] [log] [blame]
//===-- ObjectContainerBSDArchive.cpp -------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
#include "ObjectContainerBSDArchive.h"
#if defined(_WIN32) || defined(__ANDROID__) || defined(_AIX)
// Defines from ar, missing on Windows
#define SARMAG 8
#define ARFMAG "`\n"
typedef struct ar_hdr {
char ar_name[16];
char ar_date[12];
char ar_uid[6], ar_gid[6];
char ar_mode[8];
char ar_size[10];
char ar_fmag[2];
} ar_hdr;
#else
#include <ar.h>
#endif
#include "lldb/Core/Module.h"
#include "lldb/Core/ModuleSpec.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Host/FileSystem.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Utility/ArchSpec.h"
#include "lldb/Utility/LLDBLog.h"
#include "lldb/Utility/Stream.h"
#include "lldb/Utility/Timer.h"
#include "llvm/Object/Archive.h"
#include "llvm/Support/MemoryBuffer.h"
using namespace lldb;
using namespace lldb_private;
using namespace llvm::object;
LLDB_PLUGIN_DEFINE(ObjectContainerBSDArchive)
ObjectContainerBSDArchive::Object::Object() : ar_name() {}
void ObjectContainerBSDArchive::Object::Clear() {
ar_name.Clear();
modification_time = 0;
size = 0;
file_offset = 0;
file_size = 0;
}
void ObjectContainerBSDArchive::Object::Dump() const {
printf("name = \"%s\"\n", ar_name.GetCString());
printf("mtime = 0x%8.8" PRIx32 "\n", modification_time);
printf("size = 0x%8.8" PRIx32 " (%" PRIu32 ")\n", size, size);
printf("file_offset = 0x%16.16" PRIx64 " (%" PRIu64 ")\n", file_offset,
file_offset);
printf("file_size = 0x%16.16" PRIx64 " (%" PRIu64 ")\n\n", file_size,
file_size);
}
ObjectContainerBSDArchive::Archive::Archive(const lldb_private::ArchSpec &arch,
const llvm::sys::TimePoint<> &time,
lldb::offset_t file_offset,
lldb_private::DataExtractor &data,
ArchiveType archive_type)
: m_arch(arch), m_modification_time(time), m_file_offset(file_offset),
m_objects(), m_data(data), m_archive_type(archive_type) {}
Log *l = GetLog(LLDBLog::Object);
ObjectContainerBSDArchive::Archive::~Archive() = default;
size_t ObjectContainerBSDArchive::Archive::ParseObjects() {
DataExtractor &data = m_data;
std::unique_ptr<llvm::MemoryBuffer> mem_buffer =
llvm::MemoryBuffer::getMemBuffer(
llvm::StringRef((const char *)data.GetDataStart(),
data.GetByteSize()),
llvm::StringRef(),
/*RequiresNullTerminator=*/false);
auto exp_ar = llvm::object::Archive::create(mem_buffer->getMemBufferRef());
if (!exp_ar) {
LLDB_LOG_ERROR(l, exp_ar.takeError(), "failed to create archive: {0}");
return 0;
}
auto llvm_archive = std::move(exp_ar.get());
llvm::Error iter_err = llvm::Error::success();
Object obj;
for (const auto &child : llvm_archive->children(iter_err)) {
obj.Clear();
auto exp_name = child.getName();
if (exp_name) {
obj.ar_name = ConstString(exp_name.get());
} else {
LLDB_LOG_ERROR(l, exp_name.takeError(),
"failed to get archive object name: {0}");
continue;
}
auto exp_mtime = child.getLastModified();
if (exp_mtime) {
obj.modification_time =
std::chrono::duration_cast<std::chrono::seconds>(
std::chrono::time_point_cast<std::chrono::seconds>(
exp_mtime.get())
.time_since_epoch())
.count();
} else {
LLDB_LOG_ERROR(l, exp_mtime.takeError(),
"failed to get archive object time: {0}");
continue;
}
auto exp_size = child.getRawSize();
if (exp_size) {
obj.size = exp_size.get();
} else {
LLDB_LOG_ERROR(l, exp_size.takeError(),
"failed to get archive object size: {0}");
continue;
}
obj.file_offset = child.getDataOffset();
auto exp_file_size = child.getSize();
if (exp_file_size) {
obj.file_size = exp_file_size.get();
} else {
LLDB_LOG_ERROR(l, exp_file_size.takeError(),
"failed to get archive object file size: {0}");
continue;
}
m_object_name_to_index_map.Append(obj.ar_name, m_objects.size());
m_objects.push_back(obj);
}
if (iter_err) {
LLDB_LOG_ERROR(l, std::move(iter_err),
"failed to iterate over archive objects: {0}");
}
// Now sort all of the object name pointers
m_object_name_to_index_map.Sort();
return m_objects.size();
}
ObjectContainerBSDArchive::Object *
ObjectContainerBSDArchive::Archive::FindObject(
ConstString object_name, const llvm::sys::TimePoint<> &object_mod_time) {
const ObjectNameToIndexMap::Entry *match =
m_object_name_to_index_map.FindFirstValueForName(object_name);
if (!match)
return nullptr;
if (object_mod_time == llvm::sys::TimePoint<>())
return &m_objects[match->value];
const uint64_t object_modification_date = llvm::sys::toTimeT(object_mod_time);
if (m_objects[match->value].modification_time == object_modification_date)
return &m_objects[match->value];
const ObjectNameToIndexMap::Entry *next_match =
m_object_name_to_index_map.FindNextValueForName(match);
while (next_match) {
if (m_objects[next_match->value].modification_time ==
object_modification_date)
return &m_objects[next_match->value];
next_match = m_object_name_to_index_map.FindNextValueForName(next_match);
}
return nullptr;
}
ObjectContainerBSDArchive::Archive::shared_ptr
ObjectContainerBSDArchive::Archive::FindCachedArchive(
const FileSpec &file, const ArchSpec &arch,
const llvm::sys::TimePoint<> &time, lldb::offset_t file_offset) {
std::lock_guard<std::recursive_mutex> guard(Archive::GetArchiveCacheMutex());
shared_ptr archive_sp;
Archive::Map &archive_map = Archive::GetArchiveCache();
Archive::Map::iterator pos = archive_map.find(file);
// Don't cache a value for "archive_map.end()" below since we might delete an
// archive entry...
while (pos != archive_map.end() && pos->first == file) {
bool match = true;
if (arch.IsValid() &&
!pos->second->GetArchitecture().IsCompatibleMatch(arch))
match = false;
else if (file_offset != LLDB_INVALID_OFFSET &&
pos->second->GetFileOffset() != file_offset)
match = false;
if (match) {
if (pos->second->GetModificationTime() == time) {
return pos->second;
} else {
// We have a file at the same path with the same architecture whose
// modification time doesn't match. It doesn't make sense for us to
// continue to use this BSD archive since we cache only the object info
// which consists of file time info and also the file offset and file
// size of any contained objects. Since this information is now out of
// date, we won't get the correct information if we go and extract the
// file data, so we should remove the old and outdated entry.
archive_map.erase(pos);
pos = archive_map.find(file);
continue; // Continue to next iteration so we don't increment pos
// below...
}
}
++pos;
}
return archive_sp;
}
ObjectContainerBSDArchive::Archive::shared_ptr
ObjectContainerBSDArchive::Archive::ParseAndCacheArchiveForFile(
const FileSpec &file, const ArchSpec &arch,
const llvm::sys::TimePoint<> &time, lldb::offset_t file_offset,
DataExtractor &data, ArchiveType archive_type) {
shared_ptr archive_sp(
new Archive(arch, time, file_offset, data, archive_type));
if (archive_sp) {
const size_t num_objects = archive_sp->ParseObjects();
if (num_objects > 0) {
std::lock_guard<std::recursive_mutex> guard(
Archive::GetArchiveCacheMutex());
Archive::GetArchiveCache().insert(std::make_pair(file, archive_sp));
} else {
archive_sp.reset();
}
}
return archive_sp;
}
ObjectContainerBSDArchive::Archive::Map &
ObjectContainerBSDArchive::Archive::GetArchiveCache() {
static Archive::Map g_archive_map;
return g_archive_map;
}
std::recursive_mutex &
ObjectContainerBSDArchive::Archive::GetArchiveCacheMutex() {
static std::recursive_mutex g_archive_map_mutex;
return g_archive_map_mutex;
}
void ObjectContainerBSDArchive::Initialize() {
PluginManager::RegisterPlugin(GetPluginNameStatic(),
GetPluginDescriptionStatic(), CreateInstance,
GetModuleSpecifications);
}
void ObjectContainerBSDArchive::Terminate() {
PluginManager::UnregisterPlugin(CreateInstance);
}
ObjectContainer *ObjectContainerBSDArchive::CreateInstance(
const lldb::ModuleSP &module_sp, DataBufferSP &data_sp,
lldb::offset_t data_offset, const FileSpec *file,
lldb::offset_t file_offset, lldb::offset_t length) {
ConstString object_name(module_sp->GetObjectName());
if (!object_name)
return nullptr;
if (data_sp) {
// We have data, which means this is the first 512 bytes of the file Check
// to see if the magic bytes match and if they do, read the entire table of
// contents for the archive and cache it
DataExtractor data;
data.SetData(data_sp, data_offset, length);
ArchiveType archive_type = ObjectContainerBSDArchive::MagicBytesMatch(data);
if (file && data_sp && archive_type != ArchiveType::Invalid) {
LLDB_SCOPED_TIMERF(
"ObjectContainerBSDArchive::CreateInstance (module = %s, file = "
"%p, file_offset = 0x%8.8" PRIx64 ", file_size = 0x%8.8" PRIx64 ")",
module_sp->GetFileSpec().GetPath().c_str(),
static_cast<const void *>(file), static_cast<uint64_t>(file_offset),
static_cast<uint64_t>(length));
// Map the entire .a file to be sure that we don't lose any data if the
// file gets updated by a new build while this .a file is being used for
// debugging
DataBufferSP archive_data_sp =
FileSystem::Instance().CreateDataBuffer(*file, length, file_offset);
if (!archive_data_sp)
return nullptr;
lldb::offset_t archive_data_offset = 0;
Archive::shared_ptr archive_sp(Archive::FindCachedArchive(
*file, module_sp->GetArchitecture(), module_sp->GetModificationTime(),
file_offset));
std::unique_ptr<ObjectContainerBSDArchive> container_up(
new ObjectContainerBSDArchive(module_sp, archive_data_sp,
archive_data_offset, file, file_offset,
length, archive_type));
if (container_up) {
if (archive_sp) {
// We already have this archive in our cache, use it
container_up->SetArchive(archive_sp);
return container_up.release();
} else if (container_up->ParseHeader())
return container_up.release();
}
}
} else {
// No data, just check for a cached archive
Archive::shared_ptr archive_sp(Archive::FindCachedArchive(
*file, module_sp->GetArchitecture(), module_sp->GetModificationTime(),
file_offset));
if (archive_sp) {
std::unique_ptr<ObjectContainerBSDArchive> container_up(
new ObjectContainerBSDArchive(module_sp, data_sp, data_offset, file,
file_offset, length,
archive_sp->GetArchiveType()));
if (container_up) {
// We already have this archive in our cache, use it
container_up->SetArchive(archive_sp);
return container_up.release();
}
}
}
return nullptr;
}
ArchiveType
ObjectContainerBSDArchive::MagicBytesMatch(const DataExtractor &data) {
uint32_t offset = 0;
const char *armag =
(const char *)data.PeekData(offset, sizeof(ar_hdr) + SARMAG);
if (armag == nullptr)
return ArchiveType::Invalid;
ArchiveType result = ArchiveType::Invalid;
if (strncmp(armag, ArchiveMagic, SARMAG) == 0)
result = ArchiveType::Archive;
else if (strncmp(armag, ThinArchiveMagic, SARMAG) == 0)
result = ArchiveType::ThinArchive;
else
return ArchiveType::Invalid;
armag += offsetof(struct ar_hdr, ar_fmag) + SARMAG;
if (strncmp(armag, ARFMAG, 2) == 0)
return result;
return ArchiveType::Invalid;
}
ObjectContainerBSDArchive::ObjectContainerBSDArchive(
const lldb::ModuleSP &module_sp, DataBufferSP &data_sp,
lldb::offset_t data_offset, const lldb_private::FileSpec *file,
lldb::offset_t file_offset, lldb::offset_t size, ArchiveType archive_type)
: ObjectContainer(module_sp, file, file_offset, size, data_sp, data_offset),
m_archive_sp() {
m_archive_type = archive_type;
}
void ObjectContainerBSDArchive::SetArchive(Archive::shared_ptr &archive_sp) {
m_archive_sp = archive_sp;
}
ObjectContainerBSDArchive::~ObjectContainerBSDArchive() = default;
bool ObjectContainerBSDArchive::ParseHeader() {
if (m_archive_sp.get() == nullptr) {
if (m_data.GetByteSize() > 0) {
ModuleSP module_sp(GetModule());
if (module_sp) {
m_archive_sp = Archive::ParseAndCacheArchiveForFile(
m_file, module_sp->GetArchitecture(),
module_sp->GetModificationTime(), m_offset, m_data, m_archive_type);
}
// Clear the m_data that contains the entire archive data and let our
// m_archive_sp hold onto the data.
m_data.Clear();
}
}
return m_archive_sp.get() != nullptr;
}
FileSpec GetChildFileSpecificationsFromThin(llvm::StringRef childPath,
const FileSpec &parentFileSpec) {
llvm::SmallString<128> FullPath;
if (llvm::sys::path::is_absolute(childPath)) {
FullPath = childPath;
} else {
FullPath = parentFileSpec.GetDirectory().GetStringRef();
llvm::sys::path::append(FullPath, childPath);
}
FileSpec child = FileSpec(FullPath.str(), llvm::sys::path::Style::posix);
return child;
}
ObjectFileSP ObjectContainerBSDArchive::GetObjectFile(const FileSpec *file) {
ModuleSP module_sp(GetModule());
if (module_sp) {
if (module_sp->GetObjectName() && m_archive_sp) {
Object *object = m_archive_sp->FindObject(
module_sp->GetObjectName(), module_sp->GetObjectModificationTime());
if (object) {
if (m_archive_type == ArchiveType::ThinArchive) {
// Set file to child object file
FileSpec child = GetChildFileSpecificationsFromThin(
object->ar_name.GetStringRef(), m_file);
lldb::offset_t file_offset = 0;
lldb::offset_t file_size = object->size;
std::shared_ptr<DataBuffer> child_data_sp =
FileSystem::Instance().CreateDataBuffer(child, file_size,
file_offset);
if (!child_data_sp ||
child_data_sp->GetByteSize() != object->file_size)
return ObjectFileSP();
lldb::offset_t data_offset = 0;
return ObjectFile::FindPlugin(
module_sp, &child, m_offset + object->file_offset,
object->file_size, child_data_sp, data_offset);
}
lldb::offset_t data_offset = object->file_offset;
return ObjectFile::FindPlugin(
module_sp, file, m_offset + object->file_offset, object->file_size,
m_archive_sp->GetData().GetSharedDataBuffer(), data_offset);
}
}
}
return ObjectFileSP();
}
size_t ObjectContainerBSDArchive::GetModuleSpecifications(
const lldb_private::FileSpec &file, lldb::DataBufferSP &data_sp,
lldb::offset_t data_offset, lldb::offset_t file_offset,
lldb::offset_t file_size, lldb_private::ModuleSpecList &specs) {
// We have data, which means this is the first 512 bytes of the file Check to
// see if the magic bytes match and if they do, read the entire table of
// contents for the archive and cache it
DataExtractor data;
data.SetData(data_sp, data_offset, data_sp->GetByteSize());
ArchiveType archive_type = ObjectContainerBSDArchive::MagicBytesMatch(data);
if (!file || !data_sp || archive_type == ArchiveType::Invalid)
return 0;
const size_t initial_count = specs.GetSize();
llvm::sys::TimePoint<> file_mod_time =
FileSystem::Instance().GetModificationTime(file);
Archive::shared_ptr archive_sp(
Archive::FindCachedArchive(file, ArchSpec(), file_mod_time, file_offset));
bool set_archive_arch = false;
if (!archive_sp) {
set_archive_arch = true;
data_sp =
FileSystem::Instance().CreateDataBuffer(file, file_size, file_offset);
if (data_sp) {
data.SetData(data_sp, 0, data_sp->GetByteSize());
archive_sp = Archive::ParseAndCacheArchiveForFile(
file, ArchSpec(), file_mod_time, file_offset, data, archive_type);
}
}
if (archive_sp) {
const size_t num_objects = archive_sp->GetNumObjects();
for (size_t idx = 0; idx < num_objects; ++idx) {
const Object *object = archive_sp->GetObjectAtIndex(idx);
if (object) {
if (archive_sp->GetArchiveType() == ArchiveType::ThinArchive) {
if (object->ar_name.IsEmpty())
continue;
FileSpec child = GetChildFileSpecificationsFromThin(
object->ar_name.GetStringRef(), file);
if (ObjectFile::GetModuleSpecifications(child, 0, object->file_size,
specs)) {
ModuleSpec &spec =
specs.GetModuleSpecRefAtIndex(specs.GetSize() - 1);
llvm::sys::TimePoint<> object_mod_time(
std::chrono::seconds(object->modification_time));
spec.GetObjectName() = object->ar_name;
spec.SetObjectOffset(0);
spec.SetObjectSize(object->file_size);
spec.GetObjectModificationTime() = object_mod_time;
}
continue;
}
const lldb::offset_t object_file_offset =
file_offset + object->file_offset;
if (object->file_offset < file_size && file_size > object_file_offset) {
if (ObjectFile::GetModuleSpecifications(
file, object_file_offset, file_size - object_file_offset,
specs)) {
ModuleSpec &spec =
specs.GetModuleSpecRefAtIndex(specs.GetSize() - 1);
llvm::sys::TimePoint<> object_mod_time(
std::chrono::seconds(object->modification_time));
spec.GetObjectName() = object->ar_name;
spec.SetObjectOffset(object_file_offset);
spec.SetObjectSize(object->file_size);
spec.GetObjectModificationTime() = object_mod_time;
}
}
}
}
}
const size_t end_count = specs.GetSize();
size_t num_specs_added = end_count - initial_count;
if (set_archive_arch && num_specs_added > 0) {
// The archive was created but we didn't have an architecture so we need to
// set it
for (size_t i = initial_count; i < end_count; ++i) {
ModuleSpec module_spec;
if (specs.GetModuleSpecAtIndex(i, module_spec)) {
if (module_spec.GetArchitecture().IsValid()) {
archive_sp->SetArchitecture(module_spec.GetArchitecture());
break;
}
}
}
}
return num_specs_added;
}