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llvm-capstone/lldb/source/Commands/CommandObjectThread.cpp
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo 
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00

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//===-- CommandObjectThread.cpp ---------------------------------*- 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
//
//===----------------------------------------------------------------------===//
#include "CommandObjectThread.h"
#include "lldb/Core/SourceManager.h"
#include "lldb/Core/ValueObject.h"
#include "lldb/Host/Host.h"
#include "lldb/Host/OptionParser.h"
#include "lldb/Host/StringConvert.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Interpreter/OptionArgParser.h"
#include "lldb/Interpreter/Options.h"
#include "lldb/Symbol/CompileUnit.h"
#include "lldb/Symbol/Function.h"
#include "lldb/Symbol/LineEntry.h"
#include "lldb/Symbol/LineTable.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/SystemRuntime.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"
#include "lldb/Target/ThreadPlan.h"
#include "lldb/Target/ThreadPlanStepInRange.h"
#include "lldb/Target/ThreadPlanStepInstruction.h"
#include "lldb/Target/ThreadPlanStepOut.h"
#include "lldb/Target/ThreadPlanStepRange.h"
#include "lldb/Utility/State.h"
#include "lldb/lldb-private.h"
using namespace lldb;
using namespace lldb_private;
//-------------------------------------------------------------------------
// CommandObjectIterateOverThreads
//-------------------------------------------------------------------------
class CommandObjectIterateOverThreads : public CommandObjectParsed {
class UniqueStack {
public:
UniqueStack(std::stack<lldb::addr_t> stack_frames, uint32_t thread_index_id)
: m_stack_frames(stack_frames) {
m_thread_index_ids.push_back(thread_index_id);
}
void AddThread(uint32_t thread_index_id) const {
m_thread_index_ids.push_back(thread_index_id);
}
const std::vector<uint32_t> &GetUniqueThreadIndexIDs() const {
return m_thread_index_ids;
}
lldb::tid_t GetRepresentativeThread() const {
return m_thread_index_ids.front();
}
friend bool inline operator<(const UniqueStack &lhs,
const UniqueStack &rhs) {
return lhs.m_stack_frames < rhs.m_stack_frames;
}
protected:
// Mark the thread index as mutable, as we don't care about it from a const
// perspective, we only care about m_stack_frames so we keep our std::set
// sorted.
mutable std::vector<uint32_t> m_thread_index_ids;
std::stack<lldb::addr_t> m_stack_frames;
};
public:
CommandObjectIterateOverThreads(CommandInterpreter &interpreter,
const char *name, const char *help,
const char *syntax, uint32_t flags)
: CommandObjectParsed(interpreter, name, help, syntax, flags) {}
~CommandObjectIterateOverThreads() override = default;
bool DoExecute(Args &command, CommandReturnObject &result) override {
result.SetStatus(m_success_return);
bool all_threads = false;
if (command.GetArgumentCount() == 0) {
Thread *thread = m_exe_ctx.GetThreadPtr();
if (!thread || !HandleOneThread(thread->GetID(), result))
return false;
return result.Succeeded();
} else if (command.GetArgumentCount() == 1) {
all_threads = ::strcmp(command.GetArgumentAtIndex(0), "all") == 0;
m_unique_stacks = ::strcmp(command.GetArgumentAtIndex(0), "unique") == 0;
}
// Use tids instead of ThreadSPs to prevent deadlocking problems which
// result from JIT-ing code while iterating over the (locked) ThreadSP
// list.
std::vector<lldb::tid_t> tids;
if (all_threads || m_unique_stacks) {
Process *process = m_exe_ctx.GetProcessPtr();
for (ThreadSP thread_sp : process->Threads())
tids.push_back(thread_sp->GetID());
} else {
const size_t num_args = command.GetArgumentCount();
Process *process = m_exe_ctx.GetProcessPtr();
std::lock_guard<std::recursive_mutex> guard(
process->GetThreadList().GetMutex());
for (size_t i = 0; i < num_args; i++) {
bool success;
uint32_t thread_idx = StringConvert::ToUInt32(
command.GetArgumentAtIndex(i), 0, 0, &success);
if (!success) {
result.AppendErrorWithFormat("invalid thread specification: \"%s\"\n",
command.GetArgumentAtIndex(i));
result.SetStatus(eReturnStatusFailed);
return false;
}
ThreadSP thread =
process->GetThreadList().FindThreadByIndexID(thread_idx);
if (!thread) {
result.AppendErrorWithFormat("no thread with index: \"%s\"\n",
command.GetArgumentAtIndex(i));
result.SetStatus(eReturnStatusFailed);
return false;
}
tids.push_back(thread->GetID());
}
}
if (m_unique_stacks) {
// Iterate over threads, finding unique stack buckets.
std::set<UniqueStack> unique_stacks;
for (const lldb::tid_t &tid : tids) {
if (!BucketThread(tid, unique_stacks, result)) {
return false;
}
}
// Write the thread id's and unique call stacks to the output stream
Stream &strm = result.GetOutputStream();
Process *process = m_exe_ctx.GetProcessPtr();
for (const UniqueStack &stack : unique_stacks) {
// List the common thread ID's
const std::vector<uint32_t> &thread_index_ids =
stack.GetUniqueThreadIndexIDs();
strm.Format("{0} thread(s) ", thread_index_ids.size());
for (const uint32_t &thread_index_id : thread_index_ids) {
strm.Format("#{0} ", thread_index_id);
}
strm.EOL();
// List the shared call stack for this set of threads
uint32_t representative_thread_id = stack.GetRepresentativeThread();
ThreadSP thread = process->GetThreadList().FindThreadByIndexID(
representative_thread_id);
if (!HandleOneThread(thread->GetID(), result)) {
return false;
}
}
} else {
uint32_t idx = 0;
for (const lldb::tid_t &tid : tids) {
if (idx != 0 && m_add_return)
result.AppendMessage("");
if (!HandleOneThread(tid, result))
return false;
++idx;
}
}
return result.Succeeded();
}
protected:
// Override this to do whatever you need to do for one thread.
//
// If you return false, the iteration will stop, otherwise it will proceed.
// The result is set to m_success_return (defaults to
// eReturnStatusSuccessFinishResult) before the iteration, so you only need
// to set the return status in HandleOneThread if you want to indicate an
// error. If m_add_return is true, a blank line will be inserted between each
// of the listings (except the last one.)
virtual bool HandleOneThread(lldb::tid_t, CommandReturnObject &result) = 0;
bool BucketThread(lldb::tid_t tid, std::set<UniqueStack> &unique_stacks,
CommandReturnObject &result) {
// Grab the corresponding thread for the given thread id.
Process *process = m_exe_ctx.GetProcessPtr();
Thread *thread = process->GetThreadList().FindThreadByID(tid).get();
if (thread == nullptr) {
result.AppendErrorWithFormatv("Failed to process thread #{0}.\n", tid);
result.SetStatus(eReturnStatusFailed);
return false;
}
// Collect the each frame's address for this call-stack
std::stack<lldb::addr_t> stack_frames;
const uint32_t frame_count = thread->GetStackFrameCount();
for (uint32_t frame_index = 0; frame_index < frame_count; frame_index++) {
const lldb::StackFrameSP frame_sp =
thread->GetStackFrameAtIndex(frame_index);
const lldb::addr_t pc = frame_sp->GetStackID().GetPC();
stack_frames.push(pc);
}
uint32_t thread_index_id = thread->GetIndexID();
UniqueStack new_unique_stack(stack_frames, thread_index_id);
// Try to match the threads stack to and existing entry.
std::set<UniqueStack>::iterator matching_stack =
unique_stacks.find(new_unique_stack);
if (matching_stack != unique_stacks.end()) {
matching_stack->AddThread(thread_index_id);
} else {
unique_stacks.insert(new_unique_stack);
}
return true;
}
ReturnStatus m_success_return = eReturnStatusSuccessFinishResult;
bool m_unique_stacks = false;
bool m_add_return = true;
};
//-------------------------------------------------------------------------
// CommandObjectThreadBacktrace
//-------------------------------------------------------------------------
static constexpr OptionDefinition g_thread_backtrace_options[] = {
// clang-format off
{ LLDB_OPT_SET_1, false, "count", 'c', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeCount, "How many frames to display (-1 for all)" },
{ LLDB_OPT_SET_1, false, "start", 's', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeFrameIndex, "Frame in which to start the backtrace" },
{ LLDB_OPT_SET_1, false, "extended", 'e', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeBoolean, "Show the extended backtrace, if available" }
// clang-format on
};
class CommandObjectThreadBacktrace : public CommandObjectIterateOverThreads {
public:
class CommandOptions : public Options {
public:
CommandOptions() : Options() {
// Keep default values of all options in one place: OptionParsingStarting
// ()
OptionParsingStarting(nullptr);
}
~CommandOptions() override = default;
Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
ExecutionContext *execution_context) override {
Status error;
const int short_option = m_getopt_table[option_idx].val;
switch (short_option) {
case 'c': {
int32_t input_count = 0;
if (option_arg.getAsInteger(0, m_count)) {
m_count = UINT32_MAX;
error.SetErrorStringWithFormat(
"invalid integer value for option '%c'", short_option);
} else if (input_count < 0)
m_count = UINT32_MAX;
} break;
case 's':
if (option_arg.getAsInteger(0, m_start))
error.SetErrorStringWithFormat(
"invalid integer value for option '%c'", short_option);
break;
case 'e': {
bool success;
m_extended_backtrace =
OptionArgParser::ToBoolean(option_arg, false, &success);
if (!success)
error.SetErrorStringWithFormat(
"invalid boolean value for option '%c'", short_option);
} break;
default:
error.SetErrorStringWithFormat("invalid short option character '%c'",
short_option);
break;
}
return error;
}
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_count = UINT32_MAX;
m_start = 0;
m_extended_backtrace = false;
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::makeArrayRef(g_thread_backtrace_options);
}
// Instance variables to hold the values for command options.
uint32_t m_count;
uint32_t m_start;
bool m_extended_backtrace;
};
CommandObjectThreadBacktrace(CommandInterpreter &interpreter)
: CommandObjectIterateOverThreads(
interpreter, "thread backtrace",
"Show thread call stacks. Defaults to the current thread, thread "
"indexes can be specified as arguments.\n"
"Use the thread-index \"all\" to see all threads.\n"
"Use the thread-index \"unique\" to see threads grouped by unique "
"call stacks.",
nullptr,
eCommandRequiresProcess | eCommandRequiresThread |
eCommandTryTargetAPILock | eCommandProcessMustBeLaunched |
eCommandProcessMustBePaused),
m_options() {}
~CommandObjectThreadBacktrace() override = default;
Options *GetOptions() override { return &m_options; }
protected:
void DoExtendedBacktrace(Thread *thread, CommandReturnObject &result) {
SystemRuntime *runtime = thread->GetProcess()->GetSystemRuntime();
if (runtime) {
Stream &strm = result.GetOutputStream();
const std::vector<ConstString> &types =
runtime->GetExtendedBacktraceTypes();
for (auto type : types) {
ThreadSP ext_thread_sp = runtime->GetExtendedBacktraceThread(
thread->shared_from_this(), type);
if (ext_thread_sp && ext_thread_sp->IsValid()) {
const uint32_t num_frames_with_source = 0;
const bool stop_format = false;
if (ext_thread_sp->GetStatus(strm, m_options.m_start,
m_options.m_count,
num_frames_with_source,
stop_format)) {
DoExtendedBacktrace(ext_thread_sp.get(), result);
}
}
}
}
}
bool HandleOneThread(lldb::tid_t tid, CommandReturnObject &result) override {
ThreadSP thread_sp =
m_exe_ctx.GetProcessPtr()->GetThreadList().FindThreadByID(tid);
if (!thread_sp) {
result.AppendErrorWithFormat(
"thread disappeared while computing backtraces: 0x%" PRIx64 "\n",
tid);
result.SetStatus(eReturnStatusFailed);
return false;
}
Thread *thread = thread_sp.get();
Stream &strm = result.GetOutputStream();
// Only dump stack info if we processing unique stacks.
const bool only_stacks = m_unique_stacks;
// Don't show source context when doing backtraces.
const uint32_t num_frames_with_source = 0;
const bool stop_format = true;
if (!thread->GetStatus(strm, m_options.m_start, m_options.m_count,
num_frames_with_source, stop_format, only_stacks)) {
result.AppendErrorWithFormat(
"error displaying backtrace for thread: \"0x%4.4x\"\n",
thread->GetIndexID());
result.SetStatus(eReturnStatusFailed);
return false;
}
if (m_options.m_extended_backtrace) {
DoExtendedBacktrace(thread, result);
}
return true;
}
CommandOptions m_options;
};
enum StepScope { eStepScopeSource, eStepScopeInstruction };
static constexpr OptionEnumValueElement g_tri_running_mode[] = {
{eOnlyThisThread, "this-thread", "Run only this thread"},
{eAllThreads, "all-threads", "Run all threads"},
{eOnlyDuringStepping, "while-stepping",
"Run only this thread while stepping"} };
static constexpr OptionEnumValues TriRunningModes() {
return OptionEnumValues(g_tri_running_mode);
}
static constexpr OptionDefinition g_thread_step_scope_options[] = {
// clang-format off
{ LLDB_OPT_SET_1, false, "step-in-avoids-no-debug", 'a', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeBoolean, "A boolean value that sets whether stepping into functions will step over functions with no debug information." },
{ LLDB_OPT_SET_1, false, "step-out-avoids-no-debug", 'A', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeBoolean, "A boolean value, if true stepping out of functions will continue to step out till it hits a function with debug information." },
{ LLDB_OPT_SET_1, false, "count", 'c', OptionParser::eRequiredArgument, nullptr, {}, 1, eArgTypeCount, "How many times to perform the stepping operation - currently only supported for step-inst and next-inst." },
{ LLDB_OPT_SET_1, false, "end-linenumber", 'e', OptionParser::eRequiredArgument, nullptr, {}, 1, eArgTypeLineNum, "The line at which to stop stepping - defaults to the next line and only supported for step-in and step-over. You can also pass the string 'block' to step to the end of the current block. This is particularly useful in conjunction with --step-target to step through a complex calling sequence." },
{ LLDB_OPT_SET_1, false, "run-mode", 'm', OptionParser::eRequiredArgument, nullptr, TriRunningModes(), 0, eArgTypeRunMode, "Determine how to run other threads while stepping the current thread." },
{ LLDB_OPT_SET_1, false, "step-over-regexp", 'r', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeRegularExpression, "A regular expression that defines function names to not to stop at when stepping in." },
{ LLDB_OPT_SET_1, false, "step-in-target", 't', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeFunctionName, "The name of the directly called function step in should stop at when stepping into." },
{ LLDB_OPT_SET_2, false, "python-class", 'C', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypePythonClass, "The name of the class that will manage this step - only supported for Scripted Step." }
// clang-format on
};
class CommandObjectThreadStepWithTypeAndScope : public CommandObjectParsed {
public:
class CommandOptions : public Options {
public:
CommandOptions() : Options() {
// Keep default values of all options in one place: OptionParsingStarting
// ()
OptionParsingStarting(nullptr);
}
~CommandOptions() override = default;
Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
ExecutionContext *execution_context) override {
Status error;
const int short_option = m_getopt_table[option_idx].val;
switch (short_option) {
case 'a': {
bool success;
bool avoid_no_debug =
OptionArgParser::ToBoolean(option_arg, true, &success);
if (!success)
error.SetErrorStringWithFormat(
"invalid boolean value for option '%c'", short_option);
else {
m_step_in_avoid_no_debug =
avoid_no_debug ? eLazyBoolYes : eLazyBoolNo;
}
} break;
case 'A': {
bool success;
bool avoid_no_debug =
OptionArgParser::ToBoolean(option_arg, true, &success);
if (!success)
error.SetErrorStringWithFormat(
"invalid boolean value for option '%c'", short_option);
else {
m_step_out_avoid_no_debug =
avoid_no_debug ? eLazyBoolYes : eLazyBoolNo;
}
} break;
case 'c':
if (option_arg.getAsInteger(0, m_step_count))
error.SetErrorStringWithFormat("invalid step count '%s'",
option_arg.str().c_str());
break;
case 'C':
m_class_name.clear();
m_class_name.assign(option_arg);
break;
case 'm': {
auto enum_values = GetDefinitions()[option_idx].enum_values;
m_run_mode = (lldb::RunMode)OptionArgParser::ToOptionEnum(
option_arg, enum_values, eOnlyDuringStepping, error);
} break;
case 'e':
if (option_arg == "block") {
m_end_line_is_block_end = 1;
break;
}
if (option_arg.getAsInteger(0, m_end_line))
error.SetErrorStringWithFormat("invalid end line number '%s'",
option_arg.str().c_str());
break;
case 'r':
m_avoid_regexp.clear();
m_avoid_regexp.assign(option_arg);
break;
case 't':
m_step_in_target.clear();
m_step_in_target.assign(option_arg);
break;
default:
error.SetErrorStringWithFormat("invalid short option character '%c'",
short_option);
break;
}
return error;
}
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_step_in_avoid_no_debug = eLazyBoolCalculate;
m_step_out_avoid_no_debug = eLazyBoolCalculate;
m_run_mode = eOnlyDuringStepping;
// Check if we are in Non-Stop mode
TargetSP target_sp =
execution_context ? execution_context->GetTargetSP() : TargetSP();
if (target_sp && target_sp->GetNonStopModeEnabled())
m_run_mode = eOnlyThisThread;
m_avoid_regexp.clear();
m_step_in_target.clear();
m_class_name.clear();
m_step_count = 1;
m_end_line = LLDB_INVALID_LINE_NUMBER;
m_end_line_is_block_end = false;
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::makeArrayRef(g_thread_step_scope_options);
}
// Instance variables to hold the values for command options.
LazyBool m_step_in_avoid_no_debug;
LazyBool m_step_out_avoid_no_debug;
RunMode m_run_mode;
std::string m_avoid_regexp;
std::string m_step_in_target;
std::string m_class_name;
uint32_t m_step_count;
uint32_t m_end_line;
bool m_end_line_is_block_end;
};
CommandObjectThreadStepWithTypeAndScope(CommandInterpreter &interpreter,
const char *name, const char *help,
const char *syntax,
StepType step_type,
StepScope step_scope)
: CommandObjectParsed(interpreter, name, help, syntax,
eCommandRequiresProcess | eCommandRequiresThread |
eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched |
eCommandProcessMustBePaused),
m_step_type(step_type), m_step_scope(step_scope), m_options() {
CommandArgumentEntry arg;
CommandArgumentData thread_id_arg;
// Define the first (and only) variant of this arg.
thread_id_arg.arg_type = eArgTypeThreadID;
thread_id_arg.arg_repetition = eArgRepeatOptional;
// There is only one variant this argument could be; put it into the
// argument entry.
arg.push_back(thread_id_arg);
// Push the data for the first argument into the m_arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectThreadStepWithTypeAndScope() override = default;
Options *GetOptions() override { return &m_options; }
protected:
bool DoExecute(Args &command, CommandReturnObject &result) override {
Process *process = m_exe_ctx.GetProcessPtr();
bool synchronous_execution = m_interpreter.GetSynchronous();
const uint32_t num_threads = process->GetThreadList().GetSize();
Thread *thread = nullptr;
if (command.GetArgumentCount() == 0) {
thread = GetDefaultThread();
if (thread == nullptr) {
result.AppendError("no selected thread in process");
result.SetStatus(eReturnStatusFailed);
return false;
}
} else {
const char *thread_idx_cstr = command.GetArgumentAtIndex(0);
uint32_t step_thread_idx =
StringConvert::ToUInt32(thread_idx_cstr, LLDB_INVALID_INDEX32);
if (step_thread_idx == LLDB_INVALID_INDEX32) {
result.AppendErrorWithFormat("invalid thread index '%s'.\n",
thread_idx_cstr);
result.SetStatus(eReturnStatusFailed);
return false;
}
thread =
process->GetThreadList().FindThreadByIndexID(step_thread_idx).get();
if (thread == nullptr) {
result.AppendErrorWithFormat(
"Thread index %u is out of range (valid values are 0 - %u).\n",
step_thread_idx, num_threads);
result.SetStatus(eReturnStatusFailed);
return false;
}
}
if (m_step_type == eStepTypeScripted) {
if (m_options.m_class_name.empty()) {
result.AppendErrorWithFormat("empty class name for scripted step.");
result.SetStatus(eReturnStatusFailed);
return false;
} else if (!m_interpreter.GetScriptInterpreter()->CheckObjectExists(
m_options.m_class_name.c_str())) {
result.AppendErrorWithFormat(
"class for scripted step: \"%s\" does not exist.",
m_options.m_class_name.c_str());
result.SetStatus(eReturnStatusFailed);
return false;
}
}
if (m_options.m_end_line != LLDB_INVALID_LINE_NUMBER &&
m_step_type != eStepTypeInto) {
result.AppendErrorWithFormat(
"end line option is only valid for step into");
result.SetStatus(eReturnStatusFailed);
return false;
}
const bool abort_other_plans = false;
const lldb::RunMode stop_other_threads = m_options.m_run_mode;
// This is a bit unfortunate, but not all the commands in this command
// object support only while stepping, so I use the bool for them.
bool bool_stop_other_threads;
if (m_options.m_run_mode == eAllThreads)
bool_stop_other_threads = false;
else if (m_options.m_run_mode == eOnlyDuringStepping)
bool_stop_other_threads =
(m_step_type != eStepTypeOut && m_step_type != eStepTypeScripted);
else
bool_stop_other_threads = true;
ThreadPlanSP new_plan_sp;
Status new_plan_status;
if (m_step_type == eStepTypeInto) {
StackFrame *frame = thread->GetStackFrameAtIndex(0).get();
assert(frame != nullptr);
if (frame->HasDebugInformation()) {
AddressRange range;
SymbolContext sc = frame->GetSymbolContext(eSymbolContextEverything);
if (m_options.m_end_line != LLDB_INVALID_LINE_NUMBER) {
Status error;
if (!sc.GetAddressRangeFromHereToEndLine(m_options.m_end_line, range,
error)) {
result.AppendErrorWithFormat("invalid end-line option: %s.",
error.AsCString());
result.SetStatus(eReturnStatusFailed);
return false;
}
} else if (m_options.m_end_line_is_block_end) {
Status error;
Block *block = frame->GetSymbolContext(eSymbolContextBlock).block;
if (!block) {
result.AppendErrorWithFormat("Could not find the current block.");
result.SetStatus(eReturnStatusFailed);
return false;
}
AddressRange block_range;
Address pc_address = frame->GetFrameCodeAddress();
block->GetRangeContainingAddress(pc_address, block_range);
if (!block_range.GetBaseAddress().IsValid()) {
result.AppendErrorWithFormat(
"Could not find the current block address.");
result.SetStatus(eReturnStatusFailed);
return false;
}
lldb::addr_t pc_offset_in_block =
pc_address.GetFileAddress() -
block_range.GetBaseAddress().GetFileAddress();
lldb::addr_t range_length =
block_range.GetByteSize() - pc_offset_in_block;
range = AddressRange(pc_address, range_length);
} else {
range = sc.line_entry.range;
}
new_plan_sp = thread->QueueThreadPlanForStepInRange(
abort_other_plans, range,
frame->GetSymbolContext(eSymbolContextEverything),
m_options.m_step_in_target.c_str(), stop_other_threads,
new_plan_status, m_options.m_step_in_avoid_no_debug,
m_options.m_step_out_avoid_no_debug);
if (new_plan_sp && !m_options.m_avoid_regexp.empty()) {
ThreadPlanStepInRange *step_in_range_plan =
static_cast<ThreadPlanStepInRange *>(new_plan_sp.get());
step_in_range_plan->SetAvoidRegexp(m_options.m_avoid_regexp.c_str());
}
} else
new_plan_sp = thread->QueueThreadPlanForStepSingleInstruction(
false, abort_other_plans, bool_stop_other_threads, new_plan_status);
} else if (m_step_type == eStepTypeOver) {
StackFrame *frame = thread->GetStackFrameAtIndex(0).get();
if (frame->HasDebugInformation())
new_plan_sp = thread->QueueThreadPlanForStepOverRange(
abort_other_plans,
frame->GetSymbolContext(eSymbolContextEverything).line_entry,
frame->GetSymbolContext(eSymbolContextEverything),
stop_other_threads, new_plan_status,
m_options.m_step_out_avoid_no_debug);
else
new_plan_sp = thread->QueueThreadPlanForStepSingleInstruction(
true, abort_other_plans, bool_stop_other_threads, new_plan_status);
} else if (m_step_type == eStepTypeTrace) {
new_plan_sp = thread->QueueThreadPlanForStepSingleInstruction(
false, abort_other_plans, bool_stop_other_threads, new_plan_status);
} else if (m_step_type == eStepTypeTraceOver) {
new_plan_sp = thread->QueueThreadPlanForStepSingleInstruction(
true, abort_other_plans, bool_stop_other_threads, new_plan_status);
} else if (m_step_type == eStepTypeOut) {
new_plan_sp = thread->QueueThreadPlanForStepOut(
abort_other_plans, nullptr, false, bool_stop_other_threads, eVoteYes,
eVoteNoOpinion, thread->GetSelectedFrameIndex(), new_plan_status,
m_options.m_step_out_avoid_no_debug);
} else if (m_step_type == eStepTypeScripted) {
new_plan_sp = thread->QueueThreadPlanForStepScripted(
abort_other_plans, m_options.m_class_name.c_str(),
bool_stop_other_threads, new_plan_status);
} else {
result.AppendError("step type is not supported");
result.SetStatus(eReturnStatusFailed);
return false;
}
// If we got a new plan, then set it to be a master plan (User level Plans
// should be master plans so that they can be interruptible). Then resume
// the process.
if (new_plan_sp) {
new_plan_sp->SetIsMasterPlan(true);
new_plan_sp->SetOkayToDiscard(false);
if (m_options.m_step_count > 1) {
if (!new_plan_sp->SetIterationCount(m_options.m_step_count)) {
result.AppendWarning(
"step operation does not support iteration count.");
}
}
process->GetThreadList().SetSelectedThreadByID(thread->GetID());
const uint32_t iohandler_id = process->GetIOHandlerID();
StreamString stream;
Status error;
if (synchronous_execution)
error = process->ResumeSynchronous(&stream);
else
error = process->Resume();
if (!error.Success()) {
result.AppendMessage(error.AsCString());
result.SetStatus(eReturnStatusFailed);
return false;
}
// There is a race condition where this thread will return up the call
// stack to the main command handler and show an (lldb) prompt before
// HandlePrivateEvent (from PrivateStateThread) has a chance to call
// PushProcessIOHandler().
process->SyncIOHandler(iohandler_id, std::chrono::seconds(2));
if (synchronous_execution) {
// If any state changed events had anything to say, add that to the
// result
if (stream.GetSize() > 0)
result.AppendMessage(stream.GetString());
process->GetThreadList().SetSelectedThreadByID(thread->GetID());
result.SetDidChangeProcessState(true);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
} else {
result.SetStatus(eReturnStatusSuccessContinuingNoResult);
}
} else {
result.SetError(new_plan_status);
result.SetStatus(eReturnStatusFailed);
}
return result.Succeeded();
}
protected:
StepType m_step_type;
StepScope m_step_scope;
CommandOptions m_options;
};
//-------------------------------------------------------------------------
// CommandObjectThreadContinue
//-------------------------------------------------------------------------
class CommandObjectThreadContinue : public CommandObjectParsed {
public:
CommandObjectThreadContinue(CommandInterpreter &interpreter)
: CommandObjectParsed(
interpreter, "thread continue",
"Continue execution of the current target process. One "
"or more threads may be specified, by default all "
"threads continue.",
nullptr,
eCommandRequiresThread | eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched | eCommandProcessMustBePaused) {
CommandArgumentEntry arg;
CommandArgumentData thread_idx_arg;
// Define the first (and only) variant of this arg.
thread_idx_arg.arg_type = eArgTypeThreadIndex;
thread_idx_arg.arg_repetition = eArgRepeatPlus;
// There is only one variant this argument could be; put it into the
// argument entry.
arg.push_back(thread_idx_arg);
// Push the data for the first argument into the m_arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectThreadContinue() override = default;
bool DoExecute(Args &command, CommandReturnObject &result) override {
bool synchronous_execution = m_interpreter.GetSynchronous();
if (!m_interpreter.GetDebugger().GetSelectedTarget()) {
result.AppendError("invalid target, create a debug target using the "
"'target create' command");
result.SetStatus(eReturnStatusFailed);
return false;
}
Process *process = m_exe_ctx.GetProcessPtr();
if (process == nullptr) {
result.AppendError("no process exists. Cannot continue");
result.SetStatus(eReturnStatusFailed);
return false;
}
StateType state = process->GetState();
if ((state == eStateCrashed) || (state == eStateStopped) ||
(state == eStateSuspended)) {
const size_t argc = command.GetArgumentCount();
if (argc > 0) {
// These two lines appear at the beginning of both blocks in this
// if..else, but that is because we need to release the lock before
// calling process->Resume below.
std::lock_guard<std::recursive_mutex> guard(
process->GetThreadList().GetMutex());
const uint32_t num_threads = process->GetThreadList().GetSize();
std::vector<Thread *> resume_threads;
for (auto &entry : command.entries()) {
uint32_t thread_idx;
if (entry.ref.getAsInteger(0, thread_idx)) {
result.AppendErrorWithFormat(
"invalid thread index argument: \"%s\".\n", entry.c_str());
result.SetStatus(eReturnStatusFailed);
return false;
}
Thread *thread =
process->GetThreadList().FindThreadByIndexID(thread_idx).get();
if (thread) {
resume_threads.push_back(thread);
} else {
result.AppendErrorWithFormat("invalid thread index %u.\n",
thread_idx);
result.SetStatus(eReturnStatusFailed);
return false;
}
}
if (resume_threads.empty()) {
result.AppendError("no valid thread indexes were specified");
result.SetStatus(eReturnStatusFailed);
return false;
} else {
if (resume_threads.size() == 1)
result.AppendMessageWithFormat("Resuming thread: ");
else
result.AppendMessageWithFormat("Resuming threads: ");
for (uint32_t idx = 0; idx < num_threads; ++idx) {
Thread *thread =
process->GetThreadList().GetThreadAtIndex(idx).get();
std::vector<Thread *>::iterator this_thread_pos =
find(resume_threads.begin(), resume_threads.end(), thread);
if (this_thread_pos != resume_threads.end()) {
resume_threads.erase(this_thread_pos);
if (!resume_threads.empty())
result.AppendMessageWithFormat("%u, ", thread->GetIndexID());
else
result.AppendMessageWithFormat("%u ", thread->GetIndexID());
const bool override_suspend = true;
thread->SetResumeState(eStateRunning, override_suspend);
} else {
thread->SetResumeState(eStateSuspended);
}
}
result.AppendMessageWithFormat("in process %" PRIu64 "\n",
process->GetID());
}
} else {
// These two lines appear at the beginning of both blocks in this
// if..else, but that is because we need to release the lock before
// calling process->Resume below.
std::lock_guard<std::recursive_mutex> guard(
process->GetThreadList().GetMutex());
const uint32_t num_threads = process->GetThreadList().GetSize();
Thread *current_thread = GetDefaultThread();
if (current_thread == nullptr) {
result.AppendError("the process doesn't have a current thread");
result.SetStatus(eReturnStatusFailed);
return false;
}
// Set the actions that the threads should each take when resuming
for (uint32_t idx = 0; idx < num_threads; ++idx) {
Thread *thread = process->GetThreadList().GetThreadAtIndex(idx).get();
if (thread == current_thread) {
result.AppendMessageWithFormat("Resuming thread 0x%4.4" PRIx64
" in process %" PRIu64 "\n",
thread->GetID(), process->GetID());
const bool override_suspend = true;
thread->SetResumeState(eStateRunning, override_suspend);
} else {
thread->SetResumeState(eStateSuspended);
}
}
}
StreamString stream;
Status error;
if (synchronous_execution)
error = process->ResumeSynchronous(&stream);
else
error = process->Resume();
// We should not be holding the thread list lock when we do this.
if (error.Success()) {
result.AppendMessageWithFormat("Process %" PRIu64 " resuming\n",
process->GetID());
if (synchronous_execution) {
// If any state changed events had anything to say, add that to the
// result
if (stream.GetSize() > 0)
result.AppendMessage(stream.GetString());
result.SetDidChangeProcessState(true);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
} else {
result.SetStatus(eReturnStatusSuccessContinuingNoResult);
}
} else {
result.AppendErrorWithFormat("Failed to resume process: %s\n",
error.AsCString());
result.SetStatus(eReturnStatusFailed);
}
} else {
result.AppendErrorWithFormat(
"Process cannot be continued from its current state (%s).\n",
StateAsCString(state));
result.SetStatus(eReturnStatusFailed);
}
return result.Succeeded();
}
};
//-------------------------------------------------------------------------
// CommandObjectThreadUntil
//-------------------------------------------------------------------------
static constexpr OptionEnumValueElement g_duo_running_mode[] = {
{eOnlyThisThread, "this-thread", "Run only this thread"},
{eAllThreads, "all-threads", "Run all threads"} };
static constexpr OptionEnumValues DuoRunningModes() {
return OptionEnumValues(g_duo_running_mode);
}
static constexpr OptionDefinition g_thread_until_options[] = {
// clang-format off
{ LLDB_OPT_SET_1, false, "frame", 'f', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeFrameIndex, "Frame index for until operation - defaults to 0" },
{ LLDB_OPT_SET_1, false, "thread", 't', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeThreadIndex, "Thread index for the thread for until operation" },
{ LLDB_OPT_SET_1, false, "run-mode",'m', OptionParser::eRequiredArgument, nullptr, DuoRunningModes(), 0, eArgTypeRunMode, "Determine how to run other threads while stepping this one" },
{ LLDB_OPT_SET_1, false, "address", 'a', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeAddressOrExpression, "Run until we reach the specified address, or leave the function - can be specified multiple times." }
// clang-format on
};
class CommandObjectThreadUntil : public CommandObjectParsed {
public:
class CommandOptions : public Options {
public:
uint32_t m_thread_idx;
uint32_t m_frame_idx;
CommandOptions()
: Options(), m_thread_idx(LLDB_INVALID_THREAD_ID),
m_frame_idx(LLDB_INVALID_FRAME_ID) {
// Keep default values of all options in one place: OptionParsingStarting
// ()
OptionParsingStarting(nullptr);
}
~CommandOptions() override = default;
Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
ExecutionContext *execution_context) override {
Status error;
const int short_option = m_getopt_table[option_idx].val;
switch (short_option) {
case 'a': {
lldb::addr_t tmp_addr = OptionArgParser::ToAddress(
execution_context, option_arg, LLDB_INVALID_ADDRESS, &error);
if (error.Success())
m_until_addrs.push_back(tmp_addr);
} break;
case 't':
if (option_arg.getAsInteger(0, m_thread_idx)) {
m_thread_idx = LLDB_INVALID_INDEX32;
error.SetErrorStringWithFormat("invalid thread index '%s'",
option_arg.str().c_str());
}
break;
case 'f':
if (option_arg.getAsInteger(0, m_frame_idx)) {
m_frame_idx = LLDB_INVALID_FRAME_ID;
error.SetErrorStringWithFormat("invalid frame index '%s'",
option_arg.str().c_str());
}
break;
case 'm': {
auto enum_values = GetDefinitions()[option_idx].enum_values;
lldb::RunMode run_mode = (lldb::RunMode)OptionArgParser::ToOptionEnum(
option_arg, enum_values, eOnlyDuringStepping, error);
if (error.Success()) {
if (run_mode == eAllThreads)
m_stop_others = false;
else
m_stop_others = true;
}
} break;
default:
error.SetErrorStringWithFormat("invalid short option character '%c'",
short_option);
break;
}
return error;
}
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_thread_idx = LLDB_INVALID_THREAD_ID;
m_frame_idx = 0;
m_stop_others = false;
m_until_addrs.clear();
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::makeArrayRef(g_thread_until_options);
}
uint32_t m_step_thread_idx;
bool m_stop_others;
std::vector<lldb::addr_t> m_until_addrs;
// Instance variables to hold the values for command options.
};
CommandObjectThreadUntil(CommandInterpreter &interpreter)
: CommandObjectParsed(
interpreter, "thread until",
"Continue until a line number or address is reached by the "
"current or specified thread. Stops when returning from "
"the current function as a safety measure. "
"The target line number(s) are given as arguments, and if more than one"
" is provided, stepping will stop when the first one is hit.",
nullptr,
eCommandRequiresThread | eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched | eCommandProcessMustBePaused),
m_options() {
CommandArgumentEntry arg;
CommandArgumentData line_num_arg;
// Define the first (and only) variant of this arg.
line_num_arg.arg_type = eArgTypeLineNum;
line_num_arg.arg_repetition = eArgRepeatPlain;
// There is only one variant this argument could be; put it into the
// argument entry.
arg.push_back(line_num_arg);
// Push the data for the first argument into the m_arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectThreadUntil() override = default;
Options *GetOptions() override { return &m_options; }
protected:
bool DoExecute(Args &command, CommandReturnObject &result) override {
bool synchronous_execution = m_interpreter.GetSynchronous();
Target *target = m_interpreter.GetDebugger().GetSelectedTarget().get();
if (target == nullptr) {
result.AppendError("invalid target, create a debug target using the "
"'target create' command");
result.SetStatus(eReturnStatusFailed);
return false;
}
Process *process = m_exe_ctx.GetProcessPtr();
if (process == nullptr) {
result.AppendError("need a valid process to step");
result.SetStatus(eReturnStatusFailed);
} else {
Thread *thread = nullptr;
std::vector<uint32_t> line_numbers;
if (command.GetArgumentCount() >= 1) {
size_t num_args = command.GetArgumentCount();
for (size_t i = 0; i < num_args; i++) {
uint32_t line_number;
line_number = StringConvert::ToUInt32(command.GetArgumentAtIndex(i),
UINT32_MAX);
if (line_number == UINT32_MAX) {
result.AppendErrorWithFormat("invalid line number: '%s'.\n",
command.GetArgumentAtIndex(i));
result.SetStatus(eReturnStatusFailed);
return false;
} else
line_numbers.push_back(line_number);
}
} else if (m_options.m_until_addrs.empty()) {
result.AppendErrorWithFormat("No line number or address provided:\n%s",
GetSyntax().str().c_str());
result.SetStatus(eReturnStatusFailed);
return false;
}
if (m_options.m_thread_idx == LLDB_INVALID_THREAD_ID) {
thread = GetDefaultThread();
} else {
thread = process->GetThreadList()
.FindThreadByIndexID(m_options.m_thread_idx)
.get();
}
if (thread == nullptr) {
const uint32_t num_threads = process->GetThreadList().GetSize();
result.AppendErrorWithFormat(
"Thread index %u is out of range (valid values are 0 - %u).\n",
m_options.m_thread_idx, num_threads);
result.SetStatus(eReturnStatusFailed);
return false;
}
const bool abort_other_plans = false;
StackFrame *frame =
thread->GetStackFrameAtIndex(m_options.m_frame_idx).get();
if (frame == nullptr) {
result.AppendErrorWithFormat(
"Frame index %u is out of range for thread %u.\n",
m_options.m_frame_idx, m_options.m_thread_idx);
result.SetStatus(eReturnStatusFailed);
return false;
}
ThreadPlanSP new_plan_sp;
Status new_plan_status;
if (frame->HasDebugInformation()) {
// Finally we got here... Translate the given line number to a bunch
// of addresses:
SymbolContext sc(frame->GetSymbolContext(eSymbolContextCompUnit));
LineTable *line_table = nullptr;
if (sc.comp_unit)
line_table = sc.comp_unit->GetLineTable();
if (line_table == nullptr) {
result.AppendErrorWithFormat("Failed to resolve the line table for "
"frame %u of thread index %u.\n",
m_options.m_frame_idx,
m_options.m_thread_idx);
result.SetStatus(eReturnStatusFailed);
return false;
}
LineEntry function_start;
uint32_t index_ptr = 0, end_ptr;
std::vector<addr_t> address_list;
// Find the beginning & end index of the
AddressRange fun_addr_range = sc.function->GetAddressRange();
Address fun_start_addr = fun_addr_range.GetBaseAddress();
line_table->FindLineEntryByAddress(fun_start_addr, function_start,
&index_ptr);
Address fun_end_addr(fun_start_addr.GetSection(),
fun_start_addr.GetOffset() +
fun_addr_range.GetByteSize());
bool all_in_function = true;
line_table->FindLineEntryByAddress(fun_end_addr, function_start,
&end_ptr);
for (uint32_t line_number : line_numbers) {
uint32_t start_idx_ptr = index_ptr;
while (start_idx_ptr <= end_ptr) {
LineEntry line_entry;
const bool exact = false;
start_idx_ptr = sc.comp_unit->FindLineEntry(
start_idx_ptr, line_number, sc.comp_unit, exact, &line_entry);
if (start_idx_ptr == UINT32_MAX)
break;
addr_t address =
line_entry.range.GetBaseAddress().GetLoadAddress(target);
if (address != LLDB_INVALID_ADDRESS) {
if (fun_addr_range.ContainsLoadAddress(address, target))
address_list.push_back(address);
else
all_in_function = false;
}
start_idx_ptr++;
}
}
for (lldb::addr_t address : m_options.m_until_addrs) {
if (fun_addr_range.ContainsLoadAddress(address, target))
address_list.push_back(address);
else
all_in_function = false;
}
if (address_list.empty()) {
if (all_in_function)
result.AppendErrorWithFormat(
"No line entries matching until target.\n");
else
result.AppendErrorWithFormat(
"Until target outside of the current function.\n");
result.SetStatus(eReturnStatusFailed);
return false;
}
new_plan_sp = thread->QueueThreadPlanForStepUntil(
abort_other_plans, &address_list.front(), address_list.size(),
m_options.m_stop_others, m_options.m_frame_idx, new_plan_status);
if (new_plan_sp) {
// User level plans should be master plans so they can be interrupted
// (e.g. by hitting a breakpoint) and other plans executed by the
// user (stepping around the breakpoint) and then a "continue" will
// resume the original plan.
new_plan_sp->SetIsMasterPlan(true);
new_plan_sp->SetOkayToDiscard(false);
} else {
result.SetError(new_plan_status);
result.SetStatus(eReturnStatusFailed);
return false;
}
} else {
result.AppendErrorWithFormat(
"Frame index %u of thread %u has no debug information.\n",
m_options.m_frame_idx, m_options.m_thread_idx);
result.SetStatus(eReturnStatusFailed);
return false;
}
process->GetThreadList().SetSelectedThreadByID(m_options.m_thread_idx);
StreamString stream;
Status error;
if (synchronous_execution)
error = process->ResumeSynchronous(&stream);
else
error = process->Resume();
if (error.Success()) {
result.AppendMessageWithFormat("Process %" PRIu64 " resuming\n",
process->GetID());
if (synchronous_execution) {
// If any state changed events had anything to say, add that to the
// result
if (stream.GetSize() > 0)
result.AppendMessage(stream.GetString());
result.SetDidChangeProcessState(true);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
} else {
result.SetStatus(eReturnStatusSuccessContinuingNoResult);
}
} else {
result.AppendErrorWithFormat("Failed to resume process: %s.\n",
error.AsCString());
result.SetStatus(eReturnStatusFailed);
}
}
return result.Succeeded();
}
CommandOptions m_options;
};
//-------------------------------------------------------------------------
// CommandObjectThreadSelect
//-------------------------------------------------------------------------
class CommandObjectThreadSelect : public CommandObjectParsed {
public:
CommandObjectThreadSelect(CommandInterpreter &interpreter)
: CommandObjectParsed(interpreter, "thread select",
"Change the currently selected thread.", nullptr,
eCommandRequiresProcess | eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched |
eCommandProcessMustBePaused) {
CommandArgumentEntry arg;
CommandArgumentData thread_idx_arg;
// Define the first (and only) variant of this arg.
thread_idx_arg.arg_type = eArgTypeThreadIndex;
thread_idx_arg.arg_repetition = eArgRepeatPlain;
// There is only one variant this argument could be; put it into the
// argument entry.
arg.push_back(thread_idx_arg);
// Push the data for the first argument into the m_arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectThreadSelect() override = default;
protected:
bool DoExecute(Args &command, CommandReturnObject &result) override {
Process *process = m_exe_ctx.GetProcessPtr();
if (process == nullptr) {
result.AppendError("no process");
result.SetStatus(eReturnStatusFailed);
return false;
} else if (command.GetArgumentCount() != 1) {
result.AppendErrorWithFormat(
"'%s' takes exactly one thread index argument:\nUsage: %s\n",
m_cmd_name.c_str(), m_cmd_syntax.c_str());
result.SetStatus(eReturnStatusFailed);
return false;
}
uint32_t index_id =
StringConvert::ToUInt32(command.GetArgumentAtIndex(0), 0, 0);
Thread *new_thread =
process->GetThreadList().FindThreadByIndexID(index_id).get();
if (new_thread == nullptr) {
result.AppendErrorWithFormat("invalid thread #%s.\n",
command.GetArgumentAtIndex(0));
result.SetStatus(eReturnStatusFailed);
return false;
}
process->GetThreadList().SetSelectedThreadByID(new_thread->GetID(), true);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
return result.Succeeded();
}
};
//-------------------------------------------------------------------------
// CommandObjectThreadList
//-------------------------------------------------------------------------
class CommandObjectThreadList : public CommandObjectParsed {
public:
CommandObjectThreadList(CommandInterpreter &interpreter)
: CommandObjectParsed(
interpreter, "thread list",
"Show a summary of each thread in the current target process.",
"thread list",
eCommandRequiresProcess | eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched | eCommandProcessMustBePaused) {}
~CommandObjectThreadList() override = default;
protected:
bool DoExecute(Args &command, CommandReturnObject &result) override {
Stream &strm = result.GetOutputStream();
result.SetStatus(eReturnStatusSuccessFinishNoResult);
Process *process = m_exe_ctx.GetProcessPtr();
const bool only_threads_with_stop_reason = false;
const uint32_t start_frame = 0;
const uint32_t num_frames = 0;
const uint32_t num_frames_with_source = 0;
process->GetStatus(strm);
process->GetThreadStatus(strm, only_threads_with_stop_reason, start_frame,
num_frames, num_frames_with_source, false);
return result.Succeeded();
}
};
//-------------------------------------------------------------------------
// CommandObjectThreadInfo
//-------------------------------------------------------------------------
static constexpr OptionDefinition g_thread_info_options[] = {
// clang-format off
{ LLDB_OPT_SET_ALL, false, "json", 'j', OptionParser::eNoArgument, nullptr, {}, 0, eArgTypeNone, "Display the thread info in JSON format." },
{ LLDB_OPT_SET_ALL, false, "stop-info", 's', OptionParser::eNoArgument, nullptr, {}, 0, eArgTypeNone, "Display the extended stop info in JSON format." }
// clang-format on
};
class CommandObjectThreadInfo : public CommandObjectIterateOverThreads {
public:
class CommandOptions : public Options {
public:
CommandOptions() : Options() { OptionParsingStarting(nullptr); }
~CommandOptions() override = default;
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_json_thread = false;
m_json_stopinfo = false;
}
Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
ExecutionContext *execution_context) override {
const int short_option = m_getopt_table[option_idx].val;
Status error;
switch (short_option) {
case 'j':
m_json_thread = true;
break;
case 's':
m_json_stopinfo = true;
break;
default:
return Status("invalid short option character '%c'", short_option);
}
return error;
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::makeArrayRef(g_thread_info_options);
}
bool m_json_thread;
bool m_json_stopinfo;
};
CommandObjectThreadInfo(CommandInterpreter &interpreter)
: CommandObjectIterateOverThreads(
interpreter, "thread info", "Show an extended summary of one or "
"more threads. Defaults to the "
"current thread.",
"thread info",
eCommandRequiresProcess | eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched | eCommandProcessMustBePaused),
m_options() {
m_add_return = false;
}
~CommandObjectThreadInfo() override = default;
Options *GetOptions() override { return &m_options; }
bool HandleOneThread(lldb::tid_t tid, CommandReturnObject &result) override {
ThreadSP thread_sp =
m_exe_ctx.GetProcessPtr()->GetThreadList().FindThreadByID(tid);
if (!thread_sp) {
result.AppendErrorWithFormat("thread no longer exists: 0x%" PRIx64 "\n",
tid);
result.SetStatus(eReturnStatusFailed);
return false;
}
Thread *thread = thread_sp.get();
Stream &strm = result.GetOutputStream();
if (!thread->GetDescription(strm, eDescriptionLevelFull,
m_options.m_json_thread,
m_options.m_json_stopinfo)) {
result.AppendErrorWithFormat("error displaying info for thread: \"%d\"\n",
thread->GetIndexID());
result.SetStatus(eReturnStatusFailed);
return false;
}
return true;
}
CommandOptions m_options;
};
//-------------------------------------------------------------------------
// CommandObjectThreadException
//-------------------------------------------------------------------------
class CommandObjectThreadException : public CommandObjectIterateOverThreads {
public:
CommandObjectThreadException(CommandInterpreter &interpreter)
: CommandObjectIterateOverThreads(
interpreter, "thread exception",
"Display the current exception object for a thread. Defaults to "
"the current thread.",
"thread exception",
eCommandRequiresProcess | eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched | eCommandProcessMustBePaused) {}
~CommandObjectThreadException() override = default;
bool HandleOneThread(lldb::tid_t tid, CommandReturnObject &result) override {
ThreadSP thread_sp =
m_exe_ctx.GetProcessPtr()->GetThreadList().FindThreadByID(tid);
if (!thread_sp) {
result.AppendErrorWithFormat("thread no longer exists: 0x%" PRIx64 "\n",
tid);
result.SetStatus(eReturnStatusFailed);
return false;
}
Stream &strm = result.GetOutputStream();
ValueObjectSP exception_object_sp = thread_sp->GetCurrentException();
if (exception_object_sp) {
exception_object_sp->Dump(strm);
}
ThreadSP exception_thread_sp = thread_sp->GetCurrentExceptionBacktrace();
if (exception_thread_sp && exception_thread_sp->IsValid()) {
const uint32_t num_frames_with_source = 0;
const bool stop_format = false;
exception_thread_sp->GetStatus(strm, 0, UINT32_MAX,
num_frames_with_source, stop_format);
}
return true;
}
};
//-------------------------------------------------------------------------
// CommandObjectThreadReturn
//-------------------------------------------------------------------------
static constexpr OptionDefinition g_thread_return_options[] = {
// clang-format off
{ LLDB_OPT_SET_ALL, false, "from-expression", 'x', OptionParser::eNoArgument, nullptr, {}, 0, eArgTypeNone, "Return from the innermost expression evaluation." }
// clang-format on
};
class CommandObjectThreadReturn : public CommandObjectRaw {
public:
class CommandOptions : public Options {
public:
CommandOptions() : Options(), m_from_expression(false) {
// Keep default values of all options in one place: OptionParsingStarting
// ()
OptionParsingStarting(nullptr);
}
~CommandOptions() override = default;
Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
ExecutionContext *execution_context) override {
Status error;
const int short_option = m_getopt_table[option_idx].val;
switch (short_option) {
case 'x': {
bool success;
bool tmp_value =
OptionArgParser::ToBoolean(option_arg, false, &success);
if (success)
m_from_expression = tmp_value;
else {
error.SetErrorStringWithFormat(
"invalid boolean value '%s' for 'x' option",
option_arg.str().c_str());
}
} break;
default:
error.SetErrorStringWithFormat("invalid short option character '%c'",
short_option);
break;
}
return error;
}
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_from_expression = false;
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::makeArrayRef(g_thread_return_options);
}
bool m_from_expression;
// Instance variables to hold the values for command options.
};
CommandObjectThreadReturn(CommandInterpreter &interpreter)
: CommandObjectRaw(interpreter, "thread return",
"Prematurely return from a stack frame, "
"short-circuiting execution of newer frames "
"and optionally yielding a specified value. Defaults "
"to the exiting the current stack "
"frame.",
"thread return",
eCommandRequiresFrame | eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched |
eCommandProcessMustBePaused),
m_options() {
CommandArgumentEntry arg;
CommandArgumentData expression_arg;
// Define the first (and only) variant of this arg.
expression_arg.arg_type = eArgTypeExpression;
expression_arg.arg_repetition = eArgRepeatOptional;
// There is only one variant this argument could be; put it into the
// argument entry.
arg.push_back(expression_arg);
// Push the data for the first argument into the m_arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectThreadReturn() override = default;
Options *GetOptions() override { return &m_options; }
protected:
bool DoExecute(llvm::StringRef command,
CommandReturnObject &result) override {
// I am going to handle this by hand, because I don't want you to have to
// say:
// "thread return -- -5".
if (command.startswith("-x")) {
if (command.size() != 2U)
result.AppendWarning("Return values ignored when returning from user "
"called expressions");
Thread *thread = m_exe_ctx.GetThreadPtr();
Status error;
error = thread->UnwindInnermostExpression();
if (!error.Success()) {
result.AppendErrorWithFormat("Unwinding expression failed - %s.",
error.AsCString());
result.SetStatus(eReturnStatusFailed);
} else {
bool success =
thread->SetSelectedFrameByIndexNoisily(0, result.GetOutputStream());
if (success) {
m_exe_ctx.SetFrameSP(thread->GetSelectedFrame());
result.SetStatus(eReturnStatusSuccessFinishResult);
} else {
result.AppendErrorWithFormat(
"Could not select 0th frame after unwinding expression.");
result.SetStatus(eReturnStatusFailed);
}
}
return result.Succeeded();
}
ValueObjectSP return_valobj_sp;
StackFrameSP frame_sp = m_exe_ctx.GetFrameSP();
uint32_t frame_idx = frame_sp->GetFrameIndex();
if (frame_sp->IsInlined()) {
result.AppendError("Don't know how to return from inlined frames.");
result.SetStatus(eReturnStatusFailed);
return false;
}
if (!command.empty()) {
Target *target = m_exe_ctx.GetTargetPtr();
EvaluateExpressionOptions options;
options.SetUnwindOnError(true);
options.SetUseDynamic(eNoDynamicValues);
ExpressionResults exe_results = eExpressionSetupError;
exe_results = target->EvaluateExpression(command, frame_sp.get(),
return_valobj_sp, options);
if (exe_results != eExpressionCompleted) {
if (return_valobj_sp)
result.AppendErrorWithFormat(
"Error evaluating result expression: %s",
return_valobj_sp->GetError().AsCString());
else
result.AppendErrorWithFormat(
"Unknown error evaluating result expression.");
result.SetStatus(eReturnStatusFailed);
return false;
}
}
Status error;
ThreadSP thread_sp = m_exe_ctx.GetThreadSP();
const bool broadcast = true;
error = thread_sp->ReturnFromFrame(frame_sp, return_valobj_sp, broadcast);
if (!error.Success()) {
result.AppendErrorWithFormat(
"Error returning from frame %d of thread %d: %s.", frame_idx,
thread_sp->GetIndexID(), error.AsCString());
result.SetStatus(eReturnStatusFailed);
return false;
}
result.SetStatus(eReturnStatusSuccessFinishResult);
return true;
}
CommandOptions m_options;
};
//-------------------------------------------------------------------------
// CommandObjectThreadJump
//-------------------------------------------------------------------------
static constexpr OptionDefinition g_thread_jump_options[] = {
// clang-format off
{ LLDB_OPT_SET_1, false, "file", 'f', OptionParser::eRequiredArgument, nullptr, {}, CommandCompletions::eSourceFileCompletion, eArgTypeFilename, "Specifies the source file to jump to." },
{ LLDB_OPT_SET_1, true, "line", 'l', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeLineNum, "Specifies the line number to jump to." },
{ LLDB_OPT_SET_2, true, "by", 'b', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeOffset, "Jumps by a relative line offset from the current line." },
{ LLDB_OPT_SET_3, true, "address", 'a', OptionParser::eRequiredArgument, nullptr, {}, 0, eArgTypeAddressOrExpression, "Jumps to a specific address." },
{ LLDB_OPT_SET_1 | LLDB_OPT_SET_2 | LLDB_OPT_SET_3, false, "force", 'r', OptionParser::eNoArgument, nullptr, {}, 0, eArgTypeNone, "Allows the PC to leave the current function." }
// clang-format on
};
class CommandObjectThreadJump : public CommandObjectParsed {
public:
class CommandOptions : public Options {
public:
CommandOptions() : Options() { OptionParsingStarting(nullptr); }
~CommandOptions() override = default;
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_filenames.Clear();
m_line_num = 0;
m_line_offset = 0;
m_load_addr = LLDB_INVALID_ADDRESS;
m_force = false;
}
Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
ExecutionContext *execution_context) override {
const int short_option = m_getopt_table[option_idx].val;
Status error;
switch (short_option) {
case 'f':
m_filenames.AppendIfUnique(FileSpec(option_arg));
if (m_filenames.GetSize() > 1)
return Status("only one source file expected.");
break;
case 'l':
if (option_arg.getAsInteger(0, m_line_num))
return Status("invalid line number: '%s'.", option_arg.str().c_str());
break;
case 'b':
if (option_arg.getAsInteger(0, m_line_offset))
return Status("invalid line offset: '%s'.", option_arg.str().c_str());
break;
case 'a':
m_load_addr = OptionArgParser::ToAddress(execution_context, option_arg,
LLDB_INVALID_ADDRESS, &error);
break;
case 'r':
m_force = true;
break;
default:
return Status("invalid short option character '%c'", short_option);
}
return error;
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::makeArrayRef(g_thread_jump_options);
}
FileSpecList m_filenames;
uint32_t m_line_num;
int32_t m_line_offset;
lldb::addr_t m_load_addr;
bool m_force;
};
CommandObjectThreadJump(CommandInterpreter &interpreter)
: CommandObjectParsed(
interpreter, "thread jump",
"Sets the program counter to a new address.", "thread jump",
eCommandRequiresFrame | eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched | eCommandProcessMustBePaused),
m_options() {}
~CommandObjectThreadJump() override = default;
Options *GetOptions() override { return &m_options; }
protected:
bool DoExecute(Args &args, CommandReturnObject &result) override {
RegisterContext *reg_ctx = m_exe_ctx.GetRegisterContext();
StackFrame *frame = m_exe_ctx.GetFramePtr();
Thread *thread = m_exe_ctx.GetThreadPtr();
Target *target = m_exe_ctx.GetTargetPtr();
const SymbolContext &sym_ctx =
frame->GetSymbolContext(eSymbolContextLineEntry);
if (m_options.m_load_addr != LLDB_INVALID_ADDRESS) {
// Use this address directly.
Address dest = Address(m_options.m_load_addr);
lldb::addr_t callAddr = dest.GetCallableLoadAddress(target);
if (callAddr == LLDB_INVALID_ADDRESS) {
result.AppendErrorWithFormat("Invalid destination address.");
result.SetStatus(eReturnStatusFailed);
return false;
}
if (!reg_ctx->SetPC(callAddr)) {
result.AppendErrorWithFormat("Error changing PC value for thread %d.",
thread->GetIndexID());
result.SetStatus(eReturnStatusFailed);
return false;
}
} else {
// Pick either the absolute line, or work out a relative one.
int32_t line = (int32_t)m_options.m_line_num;
if (line == 0)
line = sym_ctx.line_entry.line + m_options.m_line_offset;
// Try the current file, but override if asked.
FileSpec file = sym_ctx.line_entry.file;
if (m_options.m_filenames.GetSize() == 1)
file = m_options.m_filenames.GetFileSpecAtIndex(0);
if (!file) {
result.AppendErrorWithFormat(
"No source file available for the current location.");
result.SetStatus(eReturnStatusFailed);
return false;
}
std::string warnings;
Status err = thread->JumpToLine(file, line, m_options.m_force, &warnings);
if (err.Fail()) {
result.SetError(err);
return false;
}
if (!warnings.empty())
result.AppendWarning(warnings.c_str());
}
result.SetStatus(eReturnStatusSuccessFinishResult);
return true;
}
CommandOptions m_options;
};
//-------------------------------------------------------------------------
// Next are the subcommands of CommandObjectMultiwordThreadPlan
//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
// CommandObjectThreadPlanList
//-------------------------------------------------------------------------
static constexpr OptionDefinition g_thread_plan_list_options[] = {
// clang-format off
{ LLDB_OPT_SET_1, false, "verbose", 'v', OptionParser::eNoArgument, nullptr, {}, 0, eArgTypeNone, "Display more information about the thread plans" },
{ LLDB_OPT_SET_1, false, "internal", 'i', OptionParser::eNoArgument, nullptr, {}, 0, eArgTypeNone, "Display internal as well as user thread plans" }
// clang-format on
};
class CommandObjectThreadPlanList : public CommandObjectIterateOverThreads {
public:
class CommandOptions : public Options {
public:
CommandOptions() : Options() {
// Keep default values of all options in one place: OptionParsingStarting
// ()
OptionParsingStarting(nullptr);
}
~CommandOptions() override = default;
Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
ExecutionContext *execution_context) override {
Status error;
const int short_option = m_getopt_table[option_idx].val;
switch (short_option) {
case 'i':
m_internal = true;
break;
case 'v':
m_verbose = true;
break;
default:
error.SetErrorStringWithFormat("invalid short option character '%c'",
short_option);
break;
}
return error;
}
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_verbose = false;
m_internal = false;
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::makeArrayRef(g_thread_plan_list_options);
}
// Instance variables to hold the values for command options.
bool m_verbose;
bool m_internal;
};
CommandObjectThreadPlanList(CommandInterpreter &interpreter)
: CommandObjectIterateOverThreads(
interpreter, "thread plan list",
"Show thread plans for one or more threads. If no threads are "
"specified, show the "
"current thread. Use the thread-index \"all\" to see all threads.",
nullptr,
eCommandRequiresProcess | eCommandRequiresThread |
eCommandTryTargetAPILock | eCommandProcessMustBeLaunched |
eCommandProcessMustBePaused),
m_options() {}
~CommandObjectThreadPlanList() override = default;
Options *GetOptions() override { return &m_options; }
protected:
bool HandleOneThread(lldb::tid_t tid, CommandReturnObject &result) override {
ThreadSP thread_sp =
m_exe_ctx.GetProcessPtr()->GetThreadList().FindThreadByID(tid);
if (!thread_sp) {
result.AppendErrorWithFormat("thread no longer exists: 0x%" PRIx64 "\n",
tid);
result.SetStatus(eReturnStatusFailed);
return false;
}
Thread *thread = thread_sp.get();
Stream &strm = result.GetOutputStream();
DescriptionLevel desc_level = eDescriptionLevelFull;
if (m_options.m_verbose)
desc_level = eDescriptionLevelVerbose;
thread->DumpThreadPlans(&strm, desc_level, m_options.m_internal, true);
return true;
}
CommandOptions m_options;
};
class CommandObjectThreadPlanDiscard : public CommandObjectParsed {
public:
CommandObjectThreadPlanDiscard(CommandInterpreter &interpreter)
: CommandObjectParsed(interpreter, "thread plan discard",
"Discards thread plans up to and including the "
"specified index (see 'thread plan list'.) "
"Only user visible plans can be discarded.",
nullptr,
eCommandRequiresProcess | eCommandRequiresThread |
eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched |
eCommandProcessMustBePaused) {
CommandArgumentEntry arg;
CommandArgumentData plan_index_arg;
// Define the first (and only) variant of this arg.
plan_index_arg.arg_type = eArgTypeUnsignedInteger;
plan_index_arg.arg_repetition = eArgRepeatPlain;
// There is only one variant this argument could be; put it into the
// argument entry.
arg.push_back(plan_index_arg);
// Push the data for the first argument into the m_arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectThreadPlanDiscard() override = default;
bool DoExecute(Args &args, CommandReturnObject &result) override {
Thread *thread = m_exe_ctx.GetThreadPtr();
if (args.GetArgumentCount() != 1) {
result.AppendErrorWithFormat("Too many arguments, expected one - the "
"thread plan index - but got %zu.",
args.GetArgumentCount());
result.SetStatus(eReturnStatusFailed);
return false;
}
bool success;
uint32_t thread_plan_idx =
StringConvert::ToUInt32(args.GetArgumentAtIndex(0), 0, 0, &success);
if (!success) {
result.AppendErrorWithFormat(
"Invalid thread index: \"%s\" - should be unsigned int.",
args.GetArgumentAtIndex(0));
result.SetStatus(eReturnStatusFailed);
return false;
}
if (thread_plan_idx == 0) {
result.AppendErrorWithFormat(
"You wouldn't really want me to discard the base thread plan.");
result.SetStatus(eReturnStatusFailed);
return false;
}
if (thread->DiscardUserThreadPlansUpToIndex(thread_plan_idx)) {
result.SetStatus(eReturnStatusSuccessFinishNoResult);
return true;
} else {
result.AppendErrorWithFormat(
"Could not find User thread plan with index %s.",
args.GetArgumentAtIndex(0));
result.SetStatus(eReturnStatusFailed);
return false;
}
}
};
//-------------------------------------------------------------------------
// CommandObjectMultiwordThreadPlan
//-------------------------------------------------------------------------
class CommandObjectMultiwordThreadPlan : public CommandObjectMultiword {
public:
CommandObjectMultiwordThreadPlan(CommandInterpreter &interpreter)
: CommandObjectMultiword(
interpreter, "plan",
"Commands for managing thread plans that control execution.",
"thread plan <subcommand> [<subcommand objects]") {
LoadSubCommand(
"list", CommandObjectSP(new CommandObjectThreadPlanList(interpreter)));
LoadSubCommand(
"discard",
CommandObjectSP(new CommandObjectThreadPlanDiscard(interpreter)));
}
~CommandObjectMultiwordThreadPlan() override = default;
};
//-------------------------------------------------------------------------
// CommandObjectMultiwordThread
//-------------------------------------------------------------------------
CommandObjectMultiwordThread::CommandObjectMultiwordThread(
CommandInterpreter &interpreter)
: CommandObjectMultiword(interpreter, "thread", "Commands for operating on "
"one or more threads in "
"the current process.",
"thread <subcommand> [<subcommand-options>]") {
LoadSubCommand("backtrace", CommandObjectSP(new CommandObjectThreadBacktrace(
interpreter)));
LoadSubCommand("continue",
CommandObjectSP(new CommandObjectThreadContinue(interpreter)));
LoadSubCommand("list",
CommandObjectSP(new CommandObjectThreadList(interpreter)));
LoadSubCommand("return",
CommandObjectSP(new CommandObjectThreadReturn(interpreter)));
LoadSubCommand("jump",
CommandObjectSP(new CommandObjectThreadJump(interpreter)));
LoadSubCommand("select",
CommandObjectSP(new CommandObjectThreadSelect(interpreter)));
LoadSubCommand("until",
CommandObjectSP(new CommandObjectThreadUntil(interpreter)));
LoadSubCommand("info",
CommandObjectSP(new CommandObjectThreadInfo(interpreter)));
LoadSubCommand(
"exception",
CommandObjectSP(new CommandObjectThreadException(interpreter)));
LoadSubCommand("step-in",
CommandObjectSP(new CommandObjectThreadStepWithTypeAndScope(
interpreter, "thread step-in",
"Source level single step, stepping into calls. Defaults "
"to current thread unless specified.",
nullptr, eStepTypeInto, eStepScopeSource)));
LoadSubCommand("step-out",
CommandObjectSP(new CommandObjectThreadStepWithTypeAndScope(
interpreter, "thread step-out",
"Finish executing the current stack frame and stop after "
"returning. Defaults to current thread unless specified.",
nullptr, eStepTypeOut, eStepScopeSource)));
LoadSubCommand("step-over",
CommandObjectSP(new CommandObjectThreadStepWithTypeAndScope(
interpreter, "thread step-over",
"Source level single step, stepping over calls. Defaults "
"to current thread unless specified.",
nullptr, eStepTypeOver, eStepScopeSource)));
LoadSubCommand("step-inst",
CommandObjectSP(new CommandObjectThreadStepWithTypeAndScope(
interpreter, "thread step-inst",
"Instruction level single step, stepping into calls. "
"Defaults to current thread unless specified.",
nullptr, eStepTypeTrace, eStepScopeInstruction)));
LoadSubCommand("step-inst-over",
CommandObjectSP(new CommandObjectThreadStepWithTypeAndScope(
interpreter, "thread step-inst-over",
"Instruction level single step, stepping over calls. "
"Defaults to current thread unless specified.",
nullptr, eStepTypeTraceOver, eStepScopeInstruction)));
LoadSubCommand(
"step-scripted",
CommandObjectSP(new CommandObjectThreadStepWithTypeAndScope(
interpreter, "thread step-scripted",
"Step as instructed by the script class passed in the -C option.",
nullptr, eStepTypeScripted, eStepScopeSource)));
LoadSubCommand("plan", CommandObjectSP(new CommandObjectMultiwordThreadPlan(
interpreter)));
}
CommandObjectMultiwordThread::~CommandObjectMultiwordThread() = default;
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