523 lines · cpp
1//===-- ObjectContainerBSDArchive.cpp -------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "ObjectContainerBSDArchive.h"10 11#if defined(_WIN32) || defined(_AIX)12// Defines from ar, missing on Windows13#define SARMAG 814#define ARFMAG "`\n"15 16typedef struct ar_hdr {17 char ar_name[16];18 char ar_date[12];19 char ar_uid[6], ar_gid[6];20 char ar_mode[8];21 char ar_size[10];22 char ar_fmag[2];23} ar_hdr;24#else25#include <ar.h>26#endif27 28#include "lldb/Core/Module.h"29#include "lldb/Core/ModuleSpec.h"30#include "lldb/Core/PluginManager.h"31#include "lldb/Host/FileSystem.h"32#include "lldb/Symbol/ObjectFile.h"33#include "lldb/Utility/ArchSpec.h"34#include "lldb/Utility/LLDBLog.h"35#include "lldb/Utility/Stream.h"36#include "lldb/Utility/Timer.h"37 38#include "llvm/Object/Archive.h"39#include "llvm/Support/MemoryBuffer.h"40 41using namespace lldb;42using namespace lldb_private;43 44using namespace llvm::object;45 46LLDB_PLUGIN_DEFINE(ObjectContainerBSDArchive)47 48ObjectContainerBSDArchive::Object::Object() : ar_name() {}49 50void ObjectContainerBSDArchive::Object::Clear() {51 ar_name.Clear();52 modification_time = 0;53 size = 0;54 file_offset = 0;55 file_size = 0;56}57 58void ObjectContainerBSDArchive::Object::Dump() const {59 printf("name = \"%s\"\n", ar_name.GetCString());60 printf("mtime = 0x%8.8" PRIx32 "\n", modification_time);61 printf("size = 0x%8.8" PRIx32 " (%" PRIu32 ")\n", size, size);62 printf("file_offset = 0x%16.16" PRIx64 " (%" PRIu64 ")\n", file_offset,63 file_offset);64 printf("file_size = 0x%16.16" PRIx64 " (%" PRIu64 ")\n\n", file_size,65 file_size);66}67 68ObjectContainerBSDArchive::Archive::Archive(const lldb_private::ArchSpec &arch,69 const llvm::sys::TimePoint<> &time,70 lldb::offset_t file_offset,71 lldb_private::DataExtractor &data,72 ArchiveType archive_type)73 : m_arch(arch), m_modification_time(time), m_file_offset(file_offset),74 m_objects(), m_data(data), m_archive_type(archive_type) {}75 76Log *l = GetLog(LLDBLog::Object);77ObjectContainerBSDArchive::Archive::~Archive() = default;78 79size_t ObjectContainerBSDArchive::Archive::ParseObjects() {80 DataExtractor &data = m_data;81 82 std::unique_ptr<llvm::MemoryBuffer> mem_buffer =83 llvm::MemoryBuffer::getMemBuffer(84 llvm::StringRef((const char *)data.GetDataStart(),85 data.GetByteSize()),86 llvm::StringRef(),87 /*RequiresNullTerminator=*/false);88 89 auto exp_ar = llvm::object::Archive::create(mem_buffer->getMemBufferRef());90 if (!exp_ar) {91 LLDB_LOG_ERROR(l, exp_ar.takeError(), "failed to create archive: {0}");92 return 0;93 }94 auto llvm_archive = std::move(exp_ar.get());95 96 llvm::Error iter_err = llvm::Error::success();97 Object obj;98 for (const auto &child : llvm_archive->children(iter_err)) {99 obj.Clear();100 auto exp_name = child.getName();101 if (exp_name) {102 obj.ar_name = ConstString(exp_name.get());103 } else {104 LLDB_LOG_ERROR(l, exp_name.takeError(),105 "failed to get archive object name: {0}");106 continue;107 }108 109 auto exp_mtime = child.getLastModified();110 if (exp_mtime) {111 obj.modification_time =112 std::chrono::duration_cast<std::chrono::seconds>(113 std::chrono::time_point_cast<std::chrono::seconds>(114 exp_mtime.get())115 .time_since_epoch())116 .count();117 } else {118 LLDB_LOG_ERROR(l, exp_mtime.takeError(),119 "failed to get archive object time: {0}");120 continue;121 }122 123 auto exp_size = child.getRawSize();124 if (exp_size) {125 obj.size = exp_size.get();126 } else {127 LLDB_LOG_ERROR(l, exp_size.takeError(),128 "failed to get archive object size: {0}");129 continue;130 }131 132 obj.file_offset = child.getDataOffset();133 134 auto exp_file_size = child.getSize();135 if (exp_file_size) {136 obj.file_size = exp_file_size.get();137 } else {138 LLDB_LOG_ERROR(l, exp_file_size.takeError(),139 "failed to get archive object file size: {0}");140 continue;141 }142 m_object_name_to_index_map.Append(obj.ar_name, m_objects.size());143 m_objects.push_back(obj);144 }145 if (iter_err) {146 LLDB_LOG_ERROR(l, std::move(iter_err),147 "failed to iterate over archive objects: {0}");148 }149 // Now sort all of the object name pointers150 m_object_name_to_index_map.Sort();151 return m_objects.size();152}153 154ObjectContainerBSDArchive::Object *155ObjectContainerBSDArchive::Archive::FindObject(156 ConstString object_name, const llvm::sys::TimePoint<> &object_mod_time) {157 const ObjectNameToIndexMap::Entry *match =158 m_object_name_to_index_map.FindFirstValueForName(object_name);159 if (!match)160 return nullptr;161 if (object_mod_time == llvm::sys::TimePoint<>())162 return &m_objects[match->value];163 164 const uint64_t object_modification_date = llvm::sys::toTimeT(object_mod_time);165 if (m_objects[match->value].modification_time == object_modification_date)166 return &m_objects[match->value];167 168 const ObjectNameToIndexMap::Entry *next_match =169 m_object_name_to_index_map.FindNextValueForName(match);170 while (next_match) {171 if (m_objects[next_match->value].modification_time ==172 object_modification_date)173 return &m_objects[next_match->value];174 next_match = m_object_name_to_index_map.FindNextValueForName(next_match);175 }176 177 return nullptr;178}179 180ObjectContainerBSDArchive::Archive::shared_ptr181ObjectContainerBSDArchive::Archive::FindCachedArchive(182 const FileSpec &file, const ArchSpec &arch,183 const llvm::sys::TimePoint<> &time, lldb::offset_t file_offset) {184 std::lock_guard<std::recursive_mutex> guard(Archive::GetArchiveCacheMutex());185 shared_ptr archive_sp;186 Archive::Map &archive_map = Archive::GetArchiveCache();187 Archive::Map::iterator pos = archive_map.find(file);188 // Don't cache a value for "archive_map.end()" below since we might delete an189 // archive entry...190 while (pos != archive_map.end() && pos->first == file) {191 bool match = true;192 if (arch.IsValid() &&193 !pos->second->GetArchitecture().IsCompatibleMatch(arch))194 match = false;195 else if (file_offset != LLDB_INVALID_OFFSET &&196 pos->second->GetFileOffset() != file_offset)197 match = false;198 if (match) {199 if (pos->second->GetModificationTime() == time) {200 return pos->second;201 } else {202 // We have a file at the same path with the same architecture whose203 // modification time doesn't match. It doesn't make sense for us to204 // continue to use this BSD archive since we cache only the object info205 // which consists of file time info and also the file offset and file206 // size of any contained objects. Since this information is now out of207 // date, we won't get the correct information if we go and extract the208 // file data, so we should remove the old and outdated entry.209 archive_map.erase(pos);210 pos = archive_map.find(file);211 continue; // Continue to next iteration so we don't increment pos212 // below...213 }214 }215 ++pos;216 }217 return archive_sp;218}219 220ObjectContainerBSDArchive::Archive::shared_ptr221ObjectContainerBSDArchive::Archive::ParseAndCacheArchiveForFile(222 const FileSpec &file, const ArchSpec &arch,223 const llvm::sys::TimePoint<> &time, lldb::offset_t file_offset,224 DataExtractor &data, ArchiveType archive_type) {225 shared_ptr archive_sp(226 new Archive(arch, time, file_offset, data, archive_type));227 if (archive_sp) {228 const size_t num_objects = archive_sp->ParseObjects();229 if (num_objects > 0) {230 std::lock_guard<std::recursive_mutex> guard(231 Archive::GetArchiveCacheMutex());232 Archive::GetArchiveCache().insert(std::make_pair(file, archive_sp));233 } else {234 archive_sp.reset();235 }236 }237 return archive_sp;238}239 240ObjectContainerBSDArchive::Archive::Map &241ObjectContainerBSDArchive::Archive::GetArchiveCache() {242 static Archive::Map g_archive_map;243 return g_archive_map;244}245 246std::recursive_mutex &247ObjectContainerBSDArchive::Archive::GetArchiveCacheMutex() {248 static std::recursive_mutex g_archive_map_mutex;249 return g_archive_map_mutex;250}251 252void ObjectContainerBSDArchive::Initialize() {253 PluginManager::RegisterPlugin(GetPluginNameStatic(),254 GetPluginDescriptionStatic(), CreateInstance,255 GetModuleSpecifications);256}257 258void ObjectContainerBSDArchive::Terminate() {259 PluginManager::UnregisterPlugin(CreateInstance);260}261 262ObjectContainer *ObjectContainerBSDArchive::CreateInstance(263 const lldb::ModuleSP &module_sp, DataBufferSP &data_sp,264 lldb::offset_t data_offset, const FileSpec *file,265 lldb::offset_t file_offset, lldb::offset_t length) {266 ConstString object_name(module_sp->GetObjectName());267 if (!object_name)268 return nullptr;269 270 if (data_sp) {271 // We have data, which means this is the first 512 bytes of the file Check272 // to see if the magic bytes match and if they do, read the entire table of273 // contents for the archive and cache it274 DataExtractor data;275 data.SetData(data_sp, data_offset, length);276 ArchiveType archive_type = ObjectContainerBSDArchive::MagicBytesMatch(data);277 if (file && data_sp && archive_type != ArchiveType::Invalid) {278 LLDB_SCOPED_TIMERF(279 "ObjectContainerBSDArchive::CreateInstance (module = %s, file = "280 "%p, file_offset = 0x%8.8" PRIx64 ", file_size = 0x%8.8" PRIx64 ")",281 module_sp->GetFileSpec().GetPath().c_str(),282 static_cast<const void *>(file), static_cast<uint64_t>(file_offset),283 static_cast<uint64_t>(length));284 285 // Map the entire .a file to be sure that we don't lose any data if the286 // file gets updated by a new build while this .a file is being used for287 // debugging288 DataBufferSP archive_data_sp =289 FileSystem::Instance().CreateDataBuffer(*file, length, file_offset);290 if (!archive_data_sp)291 return nullptr;292 293 lldb::offset_t archive_data_offset = 0;294 295 Archive::shared_ptr archive_sp(Archive::FindCachedArchive(296 *file, module_sp->GetArchitecture(), module_sp->GetModificationTime(),297 file_offset));298 std::unique_ptr<ObjectContainerBSDArchive> container_up(299 new ObjectContainerBSDArchive(module_sp, archive_data_sp,300 archive_data_offset, file, file_offset,301 length, archive_type));302 303 if (container_up) {304 if (archive_sp) {305 // We already have this archive in our cache, use it306 container_up->SetArchive(archive_sp);307 return container_up.release();308 } else if (container_up->ParseHeader())309 return container_up.release();310 }311 }312 } else {313 // No data, just check for a cached archive314 Archive::shared_ptr archive_sp(Archive::FindCachedArchive(315 *file, module_sp->GetArchitecture(), module_sp->GetModificationTime(),316 file_offset));317 if (archive_sp) {318 std::unique_ptr<ObjectContainerBSDArchive> container_up(319 new ObjectContainerBSDArchive(module_sp, data_sp, data_offset, file,320 file_offset, length,321 archive_sp->GetArchiveType()));322 323 if (container_up) {324 // We already have this archive in our cache, use it325 container_up->SetArchive(archive_sp);326 return container_up.release();327 }328 }329 }330 return nullptr;331}332 333ArchiveType334ObjectContainerBSDArchive::MagicBytesMatch(const DataExtractor &data) {335 uint32_t offset = 0;336 const char *armag =337 (const char *)data.PeekData(offset, sizeof(ar_hdr) + SARMAG);338 if (armag == nullptr)339 return ArchiveType::Invalid;340 ArchiveType result = ArchiveType::Invalid;341 if (strncmp(armag, ArchiveMagic, SARMAG) == 0)342 result = ArchiveType::Archive;343 else if (strncmp(armag, ThinArchiveMagic, SARMAG) == 0)344 result = ArchiveType::ThinArchive;345 else346 return ArchiveType::Invalid;347 348 armag += offsetof(struct ar_hdr, ar_fmag) + SARMAG;349 if (strncmp(armag, ARFMAG, 2) == 0)350 return result;351 return ArchiveType::Invalid;352}353 354ObjectContainerBSDArchive::ObjectContainerBSDArchive(355 const lldb::ModuleSP &module_sp, DataBufferSP &data_sp,356 lldb::offset_t data_offset, const lldb_private::FileSpec *file,357 lldb::offset_t file_offset, lldb::offset_t size, ArchiveType archive_type)358 : ObjectContainer(module_sp, file, file_offset, size, data_sp, data_offset),359 m_archive_sp() {360 m_archive_type = archive_type;361}362 363void ObjectContainerBSDArchive::SetArchive(Archive::shared_ptr &archive_sp) {364 m_archive_sp = archive_sp;365}366 367ObjectContainerBSDArchive::~ObjectContainerBSDArchive() = default;368 369bool ObjectContainerBSDArchive::ParseHeader() {370 if (m_archive_sp.get() == nullptr) {371 if (m_data.GetByteSize() > 0) {372 ModuleSP module_sp(GetModule());373 if (module_sp) {374 m_archive_sp = Archive::ParseAndCacheArchiveForFile(375 m_file, module_sp->GetArchitecture(),376 module_sp->GetModificationTime(), m_offset, m_data, m_archive_type);377 }378 // Clear the m_data that contains the entire archive data and let our379 // m_archive_sp hold onto the data.380 m_data.Clear();381 }382 }383 return m_archive_sp.get() != nullptr;384}385 386FileSpec GetChildFileSpecificationsFromThin(llvm::StringRef childPath,387 const FileSpec &parentFileSpec) {388 llvm::SmallString<128> FullPath;389 if (llvm::sys::path::is_absolute(childPath)) {390 FullPath = childPath;391 } else {392 FullPath = parentFileSpec.GetDirectory().GetStringRef();393 llvm::sys::path::append(FullPath, childPath);394 }395 FileSpec child = FileSpec(FullPath.str(), llvm::sys::path::Style::posix);396 return child;397}398 399ObjectFileSP ObjectContainerBSDArchive::GetObjectFile(const FileSpec *file) {400 ModuleSP module_sp(GetModule());401 if (module_sp) {402 if (module_sp->GetObjectName() && m_archive_sp) {403 Object *object = m_archive_sp->FindObject(404 module_sp->GetObjectName(), module_sp->GetObjectModificationTime());405 if (object) {406 if (m_archive_type == ArchiveType::ThinArchive) {407 // Set file to child object file408 FileSpec child = GetChildFileSpecificationsFromThin(409 object->ar_name.GetStringRef(), m_file);410 lldb::offset_t file_offset = 0;411 lldb::offset_t file_size = object->size;412 std::shared_ptr<DataBuffer> child_data_sp =413 FileSystem::Instance().CreateDataBuffer(child, file_size,414 file_offset);415 if (!child_data_sp ||416 child_data_sp->GetByteSize() != object->file_size)417 return ObjectFileSP();418 lldb::offset_t data_offset = 0;419 return ObjectFile::FindPlugin(420 module_sp, &child, m_offset + object->file_offset,421 object->file_size, child_data_sp, data_offset);422 }423 lldb::offset_t data_offset = object->file_offset;424 return ObjectFile::FindPlugin(425 module_sp, file, m_offset + object->file_offset, object->file_size,426 m_archive_sp->GetData().GetSharedDataBuffer(), data_offset);427 }428 }429 }430 return ObjectFileSP();431}432 433size_t ObjectContainerBSDArchive::GetModuleSpecifications(434 const lldb_private::FileSpec &file, lldb::DataBufferSP &data_sp,435 lldb::offset_t data_offset, lldb::offset_t file_offset,436 lldb::offset_t file_size, lldb_private::ModuleSpecList &specs) {437 438 // We have data, which means this is the first 512 bytes of the file Check to439 // see if the magic bytes match and if they do, read the entire table of440 // contents for the archive and cache it441 DataExtractor data;442 data.SetData(data_sp, data_offset, data_sp->GetByteSize());443 ArchiveType archive_type = ObjectContainerBSDArchive::MagicBytesMatch(data);444 if (!file || !data_sp || archive_type == ArchiveType::Invalid)445 return 0;446 447 const size_t initial_count = specs.GetSize();448 llvm::sys::TimePoint<> file_mod_time =449 FileSystem::Instance().GetModificationTime(file);450 Archive::shared_ptr archive_sp(451 Archive::FindCachedArchive(file, ArchSpec(), file_mod_time, file_offset));452 bool set_archive_arch = false;453 if (!archive_sp) {454 set_archive_arch = true;455 data_sp =456 FileSystem::Instance().CreateDataBuffer(file, file_size, file_offset);457 if (data_sp) {458 data.SetData(data_sp, 0, data_sp->GetByteSize());459 archive_sp = Archive::ParseAndCacheArchiveForFile(460 file, ArchSpec(), file_mod_time, file_offset, data, archive_type);461 }462 }463 464 if (archive_sp) {465 const size_t num_objects = archive_sp->GetNumObjects();466 for (size_t idx = 0; idx < num_objects; ++idx) {467 const Object *object = archive_sp->GetObjectAtIndex(idx);468 if (object) {469 if (archive_sp->GetArchiveType() == ArchiveType::ThinArchive) {470 if (object->ar_name.IsEmpty())471 continue;472 FileSpec child = GetChildFileSpecificationsFromThin(473 object->ar_name.GetStringRef(), file);474 if (ObjectFile::GetModuleSpecifications(child, 0, object->file_size,475 specs)) {476 ModuleSpec &spec =477 specs.GetModuleSpecRefAtIndex(specs.GetSize() - 1);478 llvm::sys::TimePoint<> object_mod_time(479 std::chrono::seconds(object->modification_time));480 spec.GetObjectName() = object->ar_name;481 spec.SetObjectOffset(0);482 spec.SetObjectSize(object->file_size);483 spec.GetObjectModificationTime() = object_mod_time;484 }485 continue;486 }487 const lldb::offset_t object_file_offset =488 file_offset + object->file_offset;489 if (object->file_offset < file_size && file_size > object_file_offset) {490 if (ObjectFile::GetModuleSpecifications(491 file, object_file_offset, file_size - object_file_offset,492 specs)) {493 ModuleSpec &spec =494 specs.GetModuleSpecRefAtIndex(specs.GetSize() - 1);495 llvm::sys::TimePoint<> object_mod_time(496 std::chrono::seconds(object->modification_time));497 spec.GetObjectName() = object->ar_name;498 spec.SetObjectOffset(object_file_offset);499 spec.SetObjectSize(object->file_size);500 spec.GetObjectModificationTime() = object_mod_time;501 }502 }503 }504 }505 }506 const size_t end_count = specs.GetSize();507 size_t num_specs_added = end_count - initial_count;508 if (set_archive_arch && num_specs_added > 0) {509 // The archive was created but we didn't have an architecture so we need to510 // set it511 for (size_t i = initial_count; i < end_count; ++i) {512 ModuleSpec module_spec;513 if (specs.GetModuleSpecAtIndex(i, module_spec)) {514 if (module_spec.GetArchitecture().IsValid()) {515 archive_sp->SetArchitecture(module_spec.GetArchitecture());516 break;517 }518 }519 }520 }521 return num_specs_added;522}523