//===-- PlatformPOSIX.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 "PlatformPOSIX.h" #include "Plugins/Platform/gdb-server/PlatformRemoteGDBServer.h" #include "Plugins/TypeSystem/Clang/TypeSystemClang.h" #include "lldb/Core/Debugger.h" #include "lldb/Core/Module.h" #include "lldb/Core/ValueObject.h" #include "lldb/Expression/DiagnosticManager.h" #include "lldb/Expression/FunctionCaller.h" #include "lldb/Expression/UserExpression.h" #include "lldb/Expression/UtilityFunction.h" #include "lldb/Host/File.h" #include "lldb/Host/FileCache.h" #include "lldb/Host/FileSystem.h" #include "lldb/Host/Host.h" #include "lldb/Host/HostInfo.h" #include "lldb/Host/ProcessLaunchInfo.h" #include "lldb/Target/DynamicLoader.h" #include "lldb/Target/ExecutionContext.h" #include "lldb/Target/Process.h" #include "lldb/Target/Thread.h" #include "lldb/Utility/DataBufferHeap.h" #include "lldb/Utility/FileSpec.h" #include "lldb/Utility/LLDBLog.h" #include "lldb/Utility/Log.h" #include "lldb/Utility/StreamString.h" #include "llvm/ADT/ScopeExit.h" #include using namespace lldb; using namespace lldb_private; /// Default Constructor PlatformPOSIX::PlatformPOSIX(bool is_host) : RemoteAwarePlatform(is_host), // This is the local host platform m_option_group_platform_rsync(new OptionGroupPlatformRSync()), m_option_group_platform_ssh(new OptionGroupPlatformSSH()), m_option_group_platform_caching(new OptionGroupPlatformCaching()) {} /// Destructor. /// /// The destructor is virtual since this class is designed to be /// inherited from by the plug-in instance. PlatformPOSIX::~PlatformPOSIX() = default; lldb_private::OptionGroupOptions *PlatformPOSIX::GetConnectionOptions( lldb_private::CommandInterpreter &interpreter) { auto iter = m_options.find(&interpreter), end = m_options.end(); if (iter == end) { std::unique_ptr options( new OptionGroupOptions()); options->Append(m_option_group_platform_rsync.get()); options->Append(m_option_group_platform_ssh.get()); options->Append(m_option_group_platform_caching.get()); m_options[&interpreter] = std::move(options); } return m_options.at(&interpreter).get(); } static uint32_t chown_file(Platform *platform, const char *path, uint32_t uid = UINT32_MAX, uint32_t gid = UINT32_MAX) { if (!platform || !path || *path == 0) return UINT32_MAX; if (uid == UINT32_MAX && gid == UINT32_MAX) return 0; // pretend I did chown correctly - actually I just didn't care StreamString command; command.PutCString("chown "); if (uid != UINT32_MAX) command.Printf("%d", uid); if (gid != UINT32_MAX) command.Printf(":%d", gid); command.Printf("%s", path); int status; platform->RunShellCommand(command.GetData(), FileSpec(), &status, nullptr, nullptr, std::chrono::seconds(10)); return status; } lldb_private::Status PlatformPOSIX::PutFile(const lldb_private::FileSpec &source, const lldb_private::FileSpec &destination, uint32_t uid, uint32_t gid) { Log *log = GetLog(LLDBLog::Platform); if (IsHost()) { if (source == destination) return Status(); // cp src dst // chown uid:gid dst std::string src_path(source.GetPath()); if (src_path.empty()) return Status("unable to get file path for source"); std::string dst_path(destination.GetPath()); if (dst_path.empty()) return Status("unable to get file path for destination"); StreamString command; command.Printf("cp %s %s", src_path.c_str(), dst_path.c_str()); int status; RunShellCommand(command.GetData(), FileSpec(), &status, nullptr, nullptr, std::chrono::seconds(10)); if (status != 0) return Status("unable to perform copy"); if (uid == UINT32_MAX && gid == UINT32_MAX) return Status(); if (chown_file(this, dst_path.c_str(), uid, gid) != 0) return Status("unable to perform chown"); return Status(); } else if (m_remote_platform_sp) { if (GetSupportsRSync()) { std::string src_path(source.GetPath()); if (src_path.empty()) return Status("unable to get file path for source"); std::string dst_path(destination.GetPath()); if (dst_path.empty()) return Status("unable to get file path for destination"); StreamString command; if (GetIgnoresRemoteHostname()) { if (!GetRSyncPrefix()) command.Printf("rsync %s %s %s", GetRSyncOpts(), src_path.c_str(), dst_path.c_str()); else command.Printf("rsync %s %s %s%s", GetRSyncOpts(), src_path.c_str(), GetRSyncPrefix(), dst_path.c_str()); } else command.Printf("rsync %s %s %s:%s", GetRSyncOpts(), src_path.c_str(), GetHostname(), dst_path.c_str()); LLDB_LOGF(log, "[PutFile] Running command: %s\n", command.GetData()); int retcode; Host::RunShellCommand(command.GetData(), FileSpec(), &retcode, nullptr, nullptr, std::chrono::minutes(1)); if (retcode == 0) { // Don't chown a local file for a remote system // if (chown_file(this,dst_path.c_str(),uid,gid) != 0) // return Status("unable to perform chown"); return Status(); } // if we are still here rsync has failed - let's try the slow way before // giving up } } return Platform::PutFile(source, destination, uid, gid); } lldb_private::Status PlatformPOSIX::GetFile( const lldb_private::FileSpec &source, // remote file path const lldb_private::FileSpec &destination) // local file path { Log *log = GetLog(LLDBLog::Platform); // Check the args, first. std::string src_path(source.GetPath()); if (src_path.empty()) return Status("unable to get file path for source"); std::string dst_path(destination.GetPath()); if (dst_path.empty()) return Status("unable to get file path for destination"); if (IsHost()) { if (source == destination) return Status("local scenario->source and destination are the same file " "path: no operation performed"); // cp src dst StreamString cp_command; cp_command.Printf("cp %s %s", src_path.c_str(), dst_path.c_str()); int status; RunShellCommand(cp_command.GetData(), FileSpec(), &status, nullptr, nullptr, std::chrono::seconds(10)); if (status != 0) return Status("unable to perform copy"); return Status(); } else if (m_remote_platform_sp) { if (GetSupportsRSync()) { StreamString command; if (GetIgnoresRemoteHostname()) { if (!GetRSyncPrefix()) command.Printf("rsync %s %s %s", GetRSyncOpts(), src_path.c_str(), dst_path.c_str()); else command.Printf("rsync %s %s%s %s", GetRSyncOpts(), GetRSyncPrefix(), src_path.c_str(), dst_path.c_str()); } else command.Printf("rsync %s %s:%s %s", GetRSyncOpts(), m_remote_platform_sp->GetHostname(), src_path.c_str(), dst_path.c_str()); LLDB_LOGF(log, "[GetFile] Running command: %s\n", command.GetData()); int retcode; Host::RunShellCommand(command.GetData(), FileSpec(), &retcode, nullptr, nullptr, std::chrono::minutes(1)); if (retcode == 0) return Status(); // If we are here, rsync has failed - let's try the slow way before // giving up } // open src and dst // read/write, read/write, read/write, ... // close src // close dst LLDB_LOGF(log, "[GetFile] Using block by block transfer....\n"); Status error; user_id_t fd_src = OpenFile(source, File::eOpenOptionReadOnly, lldb::eFilePermissionsFileDefault, error); if (fd_src == UINT64_MAX) return Status("unable to open source file"); uint32_t permissions = 0; error = GetFilePermissions(source, permissions); if (permissions == 0) permissions = lldb::eFilePermissionsFileDefault; user_id_t fd_dst = FileCache::GetInstance().OpenFile( destination, File::eOpenOptionCanCreate | File::eOpenOptionWriteOnly | File::eOpenOptionTruncate, permissions, error); if (fd_dst == UINT64_MAX) { if (error.Success()) error.SetErrorString("unable to open destination file"); } if (error.Success()) { lldb::WritableDataBufferSP buffer_sp(new DataBufferHeap(1024, 0)); uint64_t offset = 0; error.Clear(); while (error.Success()) { const uint64_t n_read = ReadFile(fd_src, offset, buffer_sp->GetBytes(), buffer_sp->GetByteSize(), error); if (error.Fail()) break; if (n_read == 0) break; if (FileCache::GetInstance().WriteFile(fd_dst, offset, buffer_sp->GetBytes(), n_read, error) != n_read) { if (!error.Fail()) error.SetErrorString("unable to write to destination file"); break; } offset += n_read; } } // Ignore the close error of src. if (fd_src != UINT64_MAX) CloseFile(fd_src, error); // And close the dst file descriptot. if (fd_dst != UINT64_MAX && !FileCache::GetInstance().CloseFile(fd_dst, error)) { if (!error.Fail()) error.SetErrorString("unable to close destination file"); } return error; } return Platform::GetFile(source, destination); } std::string PlatformPOSIX::GetPlatformSpecificConnectionInformation() { StreamString stream; if (GetSupportsRSync()) { stream.PutCString("rsync"); if ((GetRSyncOpts() && *GetRSyncOpts()) || (GetRSyncPrefix() && *GetRSyncPrefix()) || GetIgnoresRemoteHostname()) { stream.Printf(", options: "); if (GetRSyncOpts() && *GetRSyncOpts()) stream.Printf("'%s' ", GetRSyncOpts()); stream.Printf(", prefix: "); if (GetRSyncPrefix() && *GetRSyncPrefix()) stream.Printf("'%s' ", GetRSyncPrefix()); if (GetIgnoresRemoteHostname()) stream.Printf("ignore remote-hostname "); } } if (GetSupportsSSH()) { stream.PutCString("ssh"); if (GetSSHOpts() && *GetSSHOpts()) stream.Printf(", options: '%s' ", GetSSHOpts()); } if (GetLocalCacheDirectory() && *GetLocalCacheDirectory()) stream.Printf("cache dir: %s", GetLocalCacheDirectory()); if (stream.GetSize()) return std::string(stream.GetString()); else return ""; } const lldb::UnixSignalsSP &PlatformPOSIX::GetRemoteUnixSignals() { if (IsRemote() && m_remote_platform_sp) return m_remote_platform_sp->GetRemoteUnixSignals(); return Platform::GetRemoteUnixSignals(); } Status PlatformPOSIX::ConnectRemote(Args &args) { Status error; if (IsHost()) { error.SetErrorStringWithFormatv( "can't connect to the host platform '{0}', always connected", GetPluginName()); } else { if (!m_remote_platform_sp) m_remote_platform_sp = platform_gdb_server::PlatformRemoteGDBServer::CreateInstance( /*force=*/true, nullptr); if (m_remote_platform_sp && error.Success()) error = m_remote_platform_sp->ConnectRemote(args); else error.SetErrorString("failed to create a 'remote-gdb-server' platform"); if (error.Fail()) m_remote_platform_sp.reset(); } if (error.Success() && m_remote_platform_sp) { if (m_option_group_platform_rsync.get() && m_option_group_platform_ssh.get() && m_option_group_platform_caching.get()) { if (m_option_group_platform_rsync->m_rsync) { SetSupportsRSync(true); SetRSyncOpts(m_option_group_platform_rsync->m_rsync_opts.c_str()); SetRSyncPrefix(m_option_group_platform_rsync->m_rsync_prefix.c_str()); SetIgnoresRemoteHostname( m_option_group_platform_rsync->m_ignores_remote_hostname); } if (m_option_group_platform_ssh->m_ssh) { SetSupportsSSH(true); SetSSHOpts(m_option_group_platform_ssh->m_ssh_opts.c_str()); } SetLocalCacheDirectory( m_option_group_platform_caching->m_cache_dir.c_str()); } } return error; } Status PlatformPOSIX::DisconnectRemote() { Status error; if (IsHost()) { error.SetErrorStringWithFormatv( "can't disconnect from the host platform '{0}', always connected", GetPluginName()); } else { if (m_remote_platform_sp) error = m_remote_platform_sp->DisconnectRemote(); else error.SetErrorString("the platform is not currently connected"); } return error; } lldb::ProcessSP PlatformPOSIX::Attach(ProcessAttachInfo &attach_info, Debugger &debugger, Target *target, Status &error) { lldb::ProcessSP process_sp; Log *log = GetLog(LLDBLog::Platform); if (IsHost()) { if (target == nullptr) { TargetSP new_target_sp; error = debugger.GetTargetList().CreateTarget( debugger, "", "", eLoadDependentsNo, nullptr, new_target_sp); target = new_target_sp.get(); LLDB_LOGF(log, "PlatformPOSIX::%s created new target", __FUNCTION__); } else { error.Clear(); LLDB_LOGF(log, "PlatformPOSIX::%s target already existed, setting target", __FUNCTION__); } if (target && error.Success()) { if (log) { ModuleSP exe_module_sp = target->GetExecutableModule(); LLDB_LOGF(log, "PlatformPOSIX::%s set selected target to %p %s", __FUNCTION__, (void *)target, exe_module_sp ? exe_module_sp->GetFileSpec().GetPath().c_str() : ""); } process_sp = target->CreateProcess(attach_info.GetListenerForProcess(debugger), "gdb-remote", nullptr, true); if (process_sp) { ListenerSP listener_sp = attach_info.GetHijackListener(); if (listener_sp == nullptr) { listener_sp = Listener::MakeListener("lldb.PlatformPOSIX.attach.hijack"); attach_info.SetHijackListener(listener_sp); } process_sp->HijackProcessEvents(listener_sp); process_sp->SetShadowListener(attach_info.GetShadowListener()); error = process_sp->Attach(attach_info); } } } else { if (m_remote_platform_sp) process_sp = m_remote_platform_sp->Attach(attach_info, debugger, target, error); else error.SetErrorString("the platform is not currently connected"); } return process_sp; } lldb::ProcessSP PlatformPOSIX::DebugProcess(ProcessLaunchInfo &launch_info, Debugger &debugger, Target &target, Status &error) { Log *log = GetLog(LLDBLog::Platform); LLDB_LOG(log, "target {0}", &target); ProcessSP process_sp; if (!IsHost()) { if (m_remote_platform_sp) process_sp = m_remote_platform_sp->DebugProcess(launch_info, debugger, target, error); else error.SetErrorString("the platform is not currently connected"); return process_sp; } // // For local debugging, we'll insist on having ProcessGDBRemote create the // process. // // Make sure we stop at the entry point launch_info.GetFlags().Set(eLaunchFlagDebug); // We always launch the process we are going to debug in a separate process // group, since then we can handle ^C interrupts ourselves w/o having to // worry about the target getting them as well. launch_info.SetLaunchInSeparateProcessGroup(true); // Now create the gdb-remote process. LLDB_LOG(log, "having target create process with gdb-remote plugin"); process_sp = target.CreateProcess(launch_info.GetListener(), "gdb-remote", nullptr, true); if (!process_sp) { error.SetErrorString("CreateProcess() failed for gdb-remote process"); LLDB_LOG(log, "error: {0}", error); return process_sp; } LLDB_LOG(log, "successfully created process"); process_sp->HijackProcessEvents(launch_info.GetHijackListener()); process_sp->SetShadowListener(launch_info.GetShadowListener()); // Log file actions. if (log) { LLDB_LOG(log, "launching process with the following file actions:"); StreamString stream; size_t i = 0; const FileAction *file_action; while ((file_action = launch_info.GetFileActionAtIndex(i++)) != nullptr) { file_action->Dump(stream); LLDB_LOG(log, "{0}", stream.GetData()); stream.Clear(); } } // Do the launch. error = process_sp->Launch(launch_info); if (error.Success()) { // Hook up process PTY if we have one (which we should for local debugging // with llgs). int pty_fd = launch_info.GetPTY().ReleasePrimaryFileDescriptor(); if (pty_fd != PseudoTerminal::invalid_fd) { process_sp->SetSTDIOFileDescriptor(pty_fd); LLDB_LOG(log, "hooked up STDIO pty to process"); } else LLDB_LOG(log, "not using process STDIO pty"); } else { LLDB_LOG(log, "{0}", error); // FIXME figure out appropriate cleanup here. Do we delete the process? // Does our caller do that? } return process_sp; } void PlatformPOSIX::CalculateTrapHandlerSymbolNames() { m_trap_handlers.push_back(ConstString("_sigtramp")); } Status PlatformPOSIX::EvaluateLibdlExpression( lldb_private::Process *process, const char *expr_cstr, llvm::StringRef expr_prefix, lldb::ValueObjectSP &result_valobj_sp) { DynamicLoader *loader = process->GetDynamicLoader(); if (loader) { Status error = loader->CanLoadImage(); if (error.Fail()) return error; } ThreadSP thread_sp(process->GetThreadList().GetExpressionExecutionThread()); if (!thread_sp) return Status("Selected thread isn't valid"); StackFrameSP frame_sp(thread_sp->GetStackFrameAtIndex(0)); if (!frame_sp) return Status("Frame 0 isn't valid"); ExecutionContext exe_ctx; frame_sp->CalculateExecutionContext(exe_ctx); EvaluateExpressionOptions expr_options; expr_options.SetUnwindOnError(true); expr_options.SetIgnoreBreakpoints(true); expr_options.SetExecutionPolicy(eExecutionPolicyAlways); expr_options.SetLanguage(eLanguageTypeC_plus_plus); expr_options.SetTrapExceptions(false); // dlopen can't throw exceptions, so // don't do the work to trap them. expr_options.SetTimeout(process->GetUtilityExpressionTimeout()); Status expr_error; ExpressionResults result = UserExpression::Evaluate(exe_ctx, expr_options, expr_cstr, expr_prefix, result_valobj_sp, expr_error); if (result != eExpressionCompleted) return expr_error; if (result_valobj_sp->GetError().Fail()) return result_valobj_sp->GetError(); return Status(); } std::unique_ptr PlatformPOSIX::MakeLoadImageUtilityFunction(ExecutionContext &exe_ctx, Status &error) { // Remember to prepend this with the prefix from // GetLibdlFunctionDeclarations. The returned values are all in // __lldb_dlopen_result for consistency. The wrapper returns a void * but // doesn't use it because UtilityFunctions don't work with void returns at // present. // // Use lazy binding so as to not make dlopen()'s success conditional on // forcing every symbol in the library. // // In general, the debugger should allow programs to load & run with // libraries as far as they can, instead of defaulting to being super-picky // about unavailable symbols. // // The value "1" appears to imply lazy binding (RTLD_LAZY) on both Darwin // and other POSIX OSes. static const char *dlopen_wrapper_code = R"( const int RTLD_LAZY = 1; struct __lldb_dlopen_result { void *image_ptr; const char *error_str; }; extern "C" void *memcpy(void *, const void *, size_t size); extern "C" size_t strlen(const char *); void * __lldb_dlopen_wrapper (const char *name, const char *path_strings, char *buffer, __lldb_dlopen_result *result_ptr) { // This is the case where the name is the full path: if (!path_strings) { result_ptr->image_ptr = dlopen(name, RTLD_LAZY); if (result_ptr->image_ptr) result_ptr->error_str = nullptr; else result_ptr->error_str = dlerror(); return nullptr; } // This is the case where we have a list of paths: size_t name_len = strlen(name); while (path_strings && path_strings[0] != '\0') { size_t path_len = strlen(path_strings); memcpy((void *) buffer, (void *) path_strings, path_len); buffer[path_len] = '/'; char *target_ptr = buffer+path_len+1; memcpy((void *) target_ptr, (void *) name, name_len + 1); result_ptr->image_ptr = dlopen(buffer, RTLD_LAZY); if (result_ptr->image_ptr) { result_ptr->error_str = nullptr; break; } result_ptr->error_str = dlerror(); path_strings = path_strings + path_len + 1; } return nullptr; } )"; static const char *dlopen_wrapper_name = "__lldb_dlopen_wrapper"; Process *process = exe_ctx.GetProcessSP().get(); // Insert the dlopen shim defines into our generic expression: std::string expr(std::string(GetLibdlFunctionDeclarations(process))); expr.append(dlopen_wrapper_code); Status utility_error; DiagnosticManager diagnostics; auto utility_fn_or_error = process->GetTarget().CreateUtilityFunction( std::move(expr), dlopen_wrapper_name, eLanguageTypeC_plus_plus, exe_ctx); if (!utility_fn_or_error) { std::string error_str = llvm::toString(utility_fn_or_error.takeError()); error.SetErrorStringWithFormat( "dlopen error: could not create utility function: %s", error_str.c_str()); return nullptr; } std::unique_ptr dlopen_utility_func_up = std::move(*utility_fn_or_error); Value value; ValueList arguments; FunctionCaller *do_dlopen_function = nullptr; // Fetch the clang types we will need: TypeSystemClangSP scratch_ts_sp = ScratchTypeSystemClang::GetForTarget(process->GetTarget()); if (!scratch_ts_sp) return nullptr; CompilerType clang_void_pointer_type = scratch_ts_sp->GetBasicType(eBasicTypeVoid).GetPointerType(); CompilerType clang_char_pointer_type = scratch_ts_sp->GetBasicType(eBasicTypeChar).GetPointerType(); // We are passing four arguments, the basename, the list of places to look, // a buffer big enough for all the path + name combos, and // a pointer to the storage we've made for the result: value.SetValueType(Value::ValueType::Scalar); value.SetCompilerType(clang_void_pointer_type); arguments.PushValue(value); value.SetCompilerType(clang_char_pointer_type); arguments.PushValue(value); arguments.PushValue(value); arguments.PushValue(value); do_dlopen_function = dlopen_utility_func_up->MakeFunctionCaller( clang_void_pointer_type, arguments, exe_ctx.GetThreadSP(), utility_error); if (utility_error.Fail()) { error.SetErrorStringWithFormat( "dlopen error: could not make function caller: %s", utility_error.AsCString()); return nullptr; } do_dlopen_function = dlopen_utility_func_up->GetFunctionCaller(); if (!do_dlopen_function) { error.SetErrorString("dlopen error: could not get function caller."); return nullptr; } // We made a good utility function, so cache it in the process: return dlopen_utility_func_up; } uint32_t PlatformPOSIX::DoLoadImage(lldb_private::Process *process, const lldb_private::FileSpec &remote_file, const std::vector *paths, lldb_private::Status &error, lldb_private::FileSpec *loaded_image) { if (loaded_image) loaded_image->Clear(); std::string path; path = remote_file.GetPath(false); ThreadSP thread_sp = process->GetThreadList().GetExpressionExecutionThread(); if (!thread_sp) { error.SetErrorString("dlopen error: no thread available to call dlopen."); return LLDB_INVALID_IMAGE_TOKEN; } DiagnosticManager diagnostics; ExecutionContext exe_ctx; thread_sp->CalculateExecutionContext(exe_ctx); Status utility_error; UtilityFunction *dlopen_utility_func; ValueList arguments; FunctionCaller *do_dlopen_function = nullptr; // The UtilityFunction is held in the Process. Platforms don't track the // lifespan of the Targets that use them, we can't put this in the Platform. dlopen_utility_func = process->GetLoadImageUtilityFunction( this, [&]() -> std::unique_ptr { return MakeLoadImageUtilityFunction(exe_ctx, error); }); // If we couldn't make it, the error will be in error, so we can exit here. if (!dlopen_utility_func) return LLDB_INVALID_IMAGE_TOKEN; do_dlopen_function = dlopen_utility_func->GetFunctionCaller(); if (!do_dlopen_function) { error.SetErrorString("dlopen error: could not get function caller."); return LLDB_INVALID_IMAGE_TOKEN; } arguments = do_dlopen_function->GetArgumentValues(); // Now insert the path we are searching for and the result structure into the // target. uint32_t permissions = ePermissionsReadable|ePermissionsWritable; size_t path_len = path.size() + 1; lldb::addr_t path_addr = process->AllocateMemory(path_len, permissions, utility_error); if (path_addr == LLDB_INVALID_ADDRESS) { error.SetErrorStringWithFormat( "dlopen error: could not allocate memory for path: %s", utility_error.AsCString()); return LLDB_INVALID_IMAGE_TOKEN; } // Make sure we deallocate the input string memory: auto path_cleanup = llvm::make_scope_exit([process, path_addr] { // Deallocate the buffer. process->DeallocateMemory(path_addr); }); process->WriteMemory(path_addr, path.c_str(), path_len, utility_error); if (utility_error.Fail()) { error.SetErrorStringWithFormat( "dlopen error: could not write path string: %s", utility_error.AsCString()); return LLDB_INVALID_IMAGE_TOKEN; } // Make space for our return structure. It is two pointers big: the token // and the error string. const uint32_t addr_size = process->GetAddressByteSize(); lldb::addr_t return_addr = process->CallocateMemory(2*addr_size, permissions, utility_error); if (utility_error.Fail()) { error.SetErrorStringWithFormat( "dlopen error: could not allocate memory for path: %s", utility_error.AsCString()); return LLDB_INVALID_IMAGE_TOKEN; } // Make sure we deallocate the result structure memory auto return_cleanup = llvm::make_scope_exit([process, return_addr] { // Deallocate the buffer process->DeallocateMemory(return_addr); }); // This will be the address of the storage for paths, if we are using them, // or nullptr to signal we aren't. lldb::addr_t path_array_addr = 0x0; std::optional>> path_array_cleanup; // This is the address to a buffer large enough to hold the largest path // conjoined with the library name we're passing in. This is a convenience // to avoid having to call malloc in the dlopen function. lldb::addr_t buffer_addr = 0x0; std::optional>> buffer_cleanup; // Set the values into our args and write them to the target: if (paths != nullptr) { // First insert the paths into the target. This is expected to be a // continuous buffer with the strings laid out null terminated and // end to end with an empty string terminating the buffer. // We also compute the buffer's required size as we go. size_t buffer_size = 0; std::string path_array; for (auto path : *paths) { // Don't insert empty paths, they will make us abort the path // search prematurely. if (path.empty()) continue; size_t path_size = path.size(); path_array.append(path); path_array.push_back('\0'); if (path_size > buffer_size) buffer_size = path_size; } path_array.push_back('\0'); path_array_addr = process->AllocateMemory(path_array.size(), permissions, utility_error); if (path_array_addr == LLDB_INVALID_ADDRESS) { error.SetErrorStringWithFormat( "dlopen error: could not allocate memory for path array: %s", utility_error.AsCString()); return LLDB_INVALID_IMAGE_TOKEN; } // Make sure we deallocate the paths array. path_array_cleanup.emplace([process, path_array_addr]() { // Deallocate the path array. process->DeallocateMemory(path_array_addr); }); process->WriteMemory(path_array_addr, path_array.data(), path_array.size(), utility_error); if (utility_error.Fail()) { error.SetErrorStringWithFormat( "dlopen error: could not write path array: %s", utility_error.AsCString()); return LLDB_INVALID_IMAGE_TOKEN; } // Now make spaces in the target for the buffer. We need to add one for // the '/' that the utility function will insert and one for the '\0': buffer_size += path.size() + 2; buffer_addr = process->AllocateMemory(buffer_size, permissions, utility_error); if (buffer_addr == LLDB_INVALID_ADDRESS) { error.SetErrorStringWithFormat( "dlopen error: could not allocate memory for buffer: %s", utility_error.AsCString()); return LLDB_INVALID_IMAGE_TOKEN; } // Make sure we deallocate the buffer memory: buffer_cleanup.emplace([process, buffer_addr]() { // Deallocate the buffer. process->DeallocateMemory(buffer_addr); }); } arguments.GetValueAtIndex(0)->GetScalar() = path_addr; arguments.GetValueAtIndex(1)->GetScalar() = path_array_addr; arguments.GetValueAtIndex(2)->GetScalar() = buffer_addr; arguments.GetValueAtIndex(3)->GetScalar() = return_addr; lldb::addr_t func_args_addr = LLDB_INVALID_ADDRESS; diagnostics.Clear(); if (!do_dlopen_function->WriteFunctionArguments(exe_ctx, func_args_addr, arguments, diagnostics)) { error.SetErrorStringWithFormat( "dlopen error: could not write function arguments: %s", diagnostics.GetString().c_str()); return LLDB_INVALID_IMAGE_TOKEN; } // Make sure we clean up the args structure. We can't reuse it because the // Platform lives longer than the process and the Platforms don't get a // signal to clean up cached data when a process goes away. auto args_cleanup = llvm::make_scope_exit([do_dlopen_function, &exe_ctx, func_args_addr] { do_dlopen_function->DeallocateFunctionResults(exe_ctx, func_args_addr); }); // Now run the caller: EvaluateExpressionOptions options; options.SetExecutionPolicy(eExecutionPolicyAlways); options.SetLanguage(eLanguageTypeC_plus_plus); options.SetIgnoreBreakpoints(true); options.SetUnwindOnError(true); options.SetTrapExceptions(false); // dlopen can't throw exceptions, so // don't do the work to trap them. options.SetTimeout(process->GetUtilityExpressionTimeout()); options.SetIsForUtilityExpr(true); Value return_value; // Fetch the clang types we will need: TypeSystemClangSP scratch_ts_sp = ScratchTypeSystemClang::GetForTarget(process->GetTarget()); if (!scratch_ts_sp) { error.SetErrorString("dlopen error: Unable to get TypeSystemClang"); return LLDB_INVALID_IMAGE_TOKEN; } CompilerType clang_void_pointer_type = scratch_ts_sp->GetBasicType(eBasicTypeVoid).GetPointerType(); return_value.SetCompilerType(clang_void_pointer_type); ExpressionResults results = do_dlopen_function->ExecuteFunction( exe_ctx, &func_args_addr, options, diagnostics, return_value); if (results != eExpressionCompleted) { error.SetErrorStringWithFormat( "dlopen error: failed executing dlopen wrapper function: %s", diagnostics.GetString().c_str()); return LLDB_INVALID_IMAGE_TOKEN; } // Read the dlopen token from the return area: lldb::addr_t token = process->ReadPointerFromMemory(return_addr, utility_error); if (utility_error.Fail()) { error.SetErrorStringWithFormat( "dlopen error: could not read the return struct: %s", utility_error.AsCString()); return LLDB_INVALID_IMAGE_TOKEN; } // The dlopen succeeded! if (token != 0x0) { if (loaded_image && buffer_addr != 0x0) { // Capture the image which was loaded. We leave it in the buffer on // exit from the dlopen function, so we can just read it from there: std::string name_string; process->ReadCStringFromMemory(buffer_addr, name_string, utility_error); if (utility_error.Success()) loaded_image->SetFile(name_string, llvm::sys::path::Style::posix); } return process->AddImageToken(token); } // We got an error, lets read in the error string: std::string dlopen_error_str; lldb::addr_t error_addr = process->ReadPointerFromMemory(return_addr + addr_size, utility_error); if (utility_error.Fail()) { error.SetErrorStringWithFormat( "dlopen error: could not read error string: %s", utility_error.AsCString()); return LLDB_INVALID_IMAGE_TOKEN; } size_t num_chars = process->ReadCStringFromMemory(error_addr + addr_size, dlopen_error_str, utility_error); if (utility_error.Success() && num_chars > 0) error.SetErrorStringWithFormat("dlopen error: %s", dlopen_error_str.c_str()); else error.SetErrorStringWithFormat("dlopen failed for unknown reasons."); return LLDB_INVALID_IMAGE_TOKEN; } Status PlatformPOSIX::UnloadImage(lldb_private::Process *process, uint32_t image_token) { const addr_t image_addr = process->GetImagePtrFromToken(image_token); if (image_addr == LLDB_INVALID_IMAGE_TOKEN) return Status("Invalid image token"); StreamString expr; expr.Printf("dlclose((void *)0x%" PRIx64 ")", image_addr); llvm::StringRef prefix = GetLibdlFunctionDeclarations(process); lldb::ValueObjectSP result_valobj_sp; Status error = EvaluateLibdlExpression(process, expr.GetData(), prefix, result_valobj_sp); if (error.Fail()) return error; if (result_valobj_sp->GetError().Fail()) return result_valobj_sp->GetError(); Scalar scalar; if (result_valobj_sp->ResolveValue(scalar)) { if (scalar.UInt(1)) return Status("expression failed: \"%s\"", expr.GetData()); process->ResetImageToken(image_token); } return Status(); } llvm::StringRef PlatformPOSIX::GetLibdlFunctionDeclarations(lldb_private::Process *process) { return R"( extern "C" void* dlopen(const char*, int); extern "C" void* dlsym(void*, const char*); extern "C" int dlclose(void*); extern "C" char* dlerror(void); )"; } ConstString PlatformPOSIX::GetFullNameForDylib(ConstString basename) { if (basename.IsEmpty()) return basename; StreamString stream; stream.Printf("lib%s.so", basename.GetCString()); return ConstString(stream.GetString()); }