llvm-project/lldb/source/Commands/CommandObjectExpression.cpp

666 lines
26 KiB
C++

//===-- CommandObjectExpression.cpp -----------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// C Includes
// C++ Includes
// Other libraries and framework includes
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringRef.h"
// Project includes
#include "CommandObjectExpression.h"
#include "lldb/Core/Value.h"
#include "lldb/Core/ValueObjectVariable.h"
#include "lldb/DataFormatters/ValueObjectPrinter.h"
#include "Plugins/ExpressionParser/Clang/ClangExpressionVariable.h"
#include "lldb/Expression/UserExpression.h"
#include "lldb/Expression/DWARFExpression.h"
#include "lldb/Expression/REPL.h"
#include "lldb/Host/Host.h"
#include "lldb/Host/StringConvert.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Target/Language.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Symbol/Variable.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"
using namespace lldb;
using namespace lldb_private;
CommandObjectExpression::CommandOptions::CommandOptions () :
OptionGroup()
{
}
CommandObjectExpression::CommandOptions::~CommandOptions() = default;
static OptionEnumValueElement g_description_verbosity_type[] =
{
{ eLanguageRuntimeDescriptionDisplayVerbosityCompact, "compact", "Only show the description string"},
{ eLanguageRuntimeDescriptionDisplayVerbosityFull, "full", "Show the full output, including persistent variable's name and type"},
{ 0, nullptr, nullptr }
};
OptionDefinition
CommandObjectExpression::CommandOptions::g_option_table[] =
{
{ LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "all-threads", 'a', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeBoolean, "Should we run all threads if the execution doesn't complete on one thread."},
{ LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "ignore-breakpoints", 'i', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeBoolean, "Ignore breakpoint hits while running expressions"},
{ LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "timeout", 't', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeUnsignedInteger, "Timeout value (in microseconds) for running the expression."},
{ LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "unwind-on-error", 'u', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeBoolean, "Clean up program state if the expression causes a crash, or raises a signal. Note, unlike gdb hitting a breakpoint is controlled by another option (-i)."},
{ LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "debug", 'g', OptionParser::eNoArgument , nullptr, nullptr, 0, eArgTypeNone, "When specified, debug the JIT code by setting a breakpoint on the first instruction and forcing breakpoints to not be ignored (-i0) and no unwinding to happen on error (-u0)."},
{ LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "language", 'l', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeLanguage, "Specifies the Language to use when parsing the expression. If not set the target.language setting is used." },
{ LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "apply-fixits", 'X', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeLanguage, "If true, simple fix-it hints will be automatically applied to the expression." },
{ LLDB_OPT_SET_1, false, "description-verbosity", 'v', OptionParser::eOptionalArgument, nullptr, g_description_verbosity_type, 0, eArgTypeDescriptionVerbosity, "How verbose should the output of this expression be, if the object description is asked for."},
{ LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "top-level", 'p', OptionParser::eNoArgument , NULL, NULL, 0, eArgTypeNone, "Interpret the expression as top-level definitions rather than code to be immediately executed."},
{ LLDB_OPT_SET_1 | LLDB_OPT_SET_2, false, "allow-jit", 'j', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeBoolean, "Controls whether the expression can fall back to being JITted if it's not supported by the interpreter (defaults to true)."}
};
uint32_t
CommandObjectExpression::CommandOptions::GetNumDefinitions ()
{
return llvm::array_lengthof(g_option_table);
}
Error
CommandObjectExpression::CommandOptions::SetOptionValue (CommandInterpreter &interpreter,
uint32_t option_idx,
const char *option_arg)
{
Error error;
const int short_option = g_option_table[option_idx].short_option;
switch (short_option)
{
case 'l':
language = Language::GetLanguageTypeFromString (option_arg);
if (language == eLanguageTypeUnknown)
error.SetErrorStringWithFormat ("unknown language type: '%s' for expression", option_arg);
break;
case 'a':
{
bool success;
bool result;
result = Args::StringToBoolean(option_arg, true, &success);
if (!success)
error.SetErrorStringWithFormat("invalid all-threads value setting: \"%s\"", option_arg);
else
try_all_threads = result;
}
break;
case 'i':
{
bool success;
bool tmp_value = Args::StringToBoolean(option_arg, true, &success);
if (success)
ignore_breakpoints = tmp_value;
else
error.SetErrorStringWithFormat("could not convert \"%s\" to a boolean value.", option_arg);
break;
}
case 'j':
{
bool success;
bool tmp_value = Args::StringToBoolean(option_arg, true, &success);
if (success)
allow_jit = tmp_value;
else
error.SetErrorStringWithFormat("could not convert \"%s\" to a boolean value.", option_arg);
break;
}
case 't':
{
bool success;
uint32_t result;
result = StringConvert::ToUInt32(option_arg, 0, 0, &success);
if (success)
timeout = result;
else
error.SetErrorStringWithFormat ("invalid timeout setting \"%s\"", option_arg);
}
break;
case 'u':
{
bool success;
bool tmp_value = Args::StringToBoolean(option_arg, true, &success);
if (success)
unwind_on_error = tmp_value;
else
error.SetErrorStringWithFormat("could not convert \"%s\" to a boolean value.", option_arg);
break;
}
case 'v':
if (!option_arg)
{
m_verbosity = eLanguageRuntimeDescriptionDisplayVerbosityFull;
break;
}
m_verbosity = (LanguageRuntimeDescriptionDisplayVerbosity) Args::StringToOptionEnum(option_arg, g_option_table[option_idx].enum_values, 0, error);
if (!error.Success())
error.SetErrorStringWithFormat ("unrecognized value for description-verbosity '%s'", option_arg);
break;
case 'g':
debug = true;
unwind_on_error = false;
ignore_breakpoints = false;
break;
case 'p':
top_level = true;
break;
case 'X':
{
bool success;
bool tmp_value = Args::StringToBoolean(option_arg, true, &success);
if (success)
auto_apply_fixits = tmp_value ? eLazyBoolYes : eLazyBoolNo;
else
error.SetErrorStringWithFormat("could not convert \"%s\" to a boolean value.", option_arg);
break;
}
default:
error.SetErrorStringWithFormat("invalid short option character '%c'", short_option);
break;
}
return error;
}
void
CommandObjectExpression::CommandOptions::OptionParsingStarting (CommandInterpreter &interpreter)
{
Process *process = interpreter.GetExecutionContext().GetProcessPtr();
if (process != nullptr)
{
ignore_breakpoints = process->GetIgnoreBreakpointsInExpressions();
unwind_on_error = process->GetUnwindOnErrorInExpressions();
}
else
{
ignore_breakpoints = true;
unwind_on_error = true;
}
show_summary = true;
try_all_threads = true;
timeout = 0;
debug = false;
language = eLanguageTypeUnknown;
m_verbosity = eLanguageRuntimeDescriptionDisplayVerbosityCompact;
auto_apply_fixits = eLazyBoolCalculate;
top_level = false;
allow_jit = true;
}
const OptionDefinition*
CommandObjectExpression::CommandOptions::GetDefinitions ()
{
return g_option_table;
}
CommandObjectExpression::CommandObjectExpression (CommandInterpreter &interpreter) :
CommandObjectRaw(interpreter,
"expression",
"Evaluate an expression in the current program context, using user defined variables and variables currently in scope.",
nullptr,
eCommandProcessMustBePaused | eCommandTryTargetAPILock),
IOHandlerDelegate (IOHandlerDelegate::Completion::Expression),
m_option_group (interpreter),
m_format_options (eFormatDefault),
m_repl_option (LLDB_OPT_SET_1, false, "repl", 'r', "Drop into REPL", false, true),
m_command_options (),
m_expr_line_count (0),
m_expr_lines ()
{
SetHelpLong(
R"(
Timeouts:
)" " If the expression can be evaluated statically (without running code) then it will be. \
Otherwise, by default the expression will run on the current thread with a short timeout: \
currently .25 seconds. If it doesn't return in that time, the evaluation will be interrupted \
and resumed with all threads running. You can use the -a option to disable retrying on all \
threads. You can use the -t option to set a shorter timeout." R"(
User defined variables:
)" " You can define your own variables for convenience or to be used in subsequent expressions. \
You define them the same way you would define variables in C. If the first character of \
your user defined variable is a $, then the variable's value will be available in future \
expressions, otherwise it will just be available in the current expression." R"(
Continuing evaluation after a breakpoint:
)" " If the \"-i false\" option is used, and execution is interrupted by a breakpoint hit, once \
you are done with your investigation, you can either remove the expression execution frames \
from the stack with \"thread return -x\" or if you are still interested in the expression result \
you can issue the \"continue\" command and the expression evaluation will complete and the \
expression result will be available using the \"thread.completed-expression\" key in the thread \
format." R"(
Examples:
expr my_struct->a = my_array[3]
expr -f bin -- (index * 8) + 5
expr unsigned int $foo = 5
expr char c[] = \"foo\"; c[0])"
);
CommandArgumentEntry arg;
CommandArgumentData expression_arg;
// Define the first (and only) variant of this arg.
expression_arg.arg_type = eArgTypeExpression;
expression_arg.arg_repetition = eArgRepeatPlain;
// 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);
// Add the "--format" and "--gdb-format"
m_option_group.Append (&m_format_options, OptionGroupFormat::OPTION_GROUP_FORMAT | OptionGroupFormat::OPTION_GROUP_GDB_FMT, LLDB_OPT_SET_1);
m_option_group.Append (&m_command_options);
m_option_group.Append (&m_varobj_options, LLDB_OPT_SET_ALL, LLDB_OPT_SET_1 | LLDB_OPT_SET_2);
m_option_group.Append (&m_repl_option, LLDB_OPT_SET_ALL, LLDB_OPT_SET_3);
m_option_group.Finalize();
}
CommandObjectExpression::~CommandObjectExpression() = default;
Options *
CommandObjectExpression::GetOptions ()
{
return &m_option_group;
}
static lldb_private::Error
CanBeUsedForElementCountPrinting (ValueObject& valobj)
{
CompilerType type(valobj.GetCompilerType());
CompilerType pointee;
if (!type.IsPointerType(&pointee))
return Error("as it does not refer to a pointer");
if (pointee.IsVoidType())
return Error("as it refers to a pointer to void");
return Error();
}
bool
CommandObjectExpression::EvaluateExpression(const char *expr,
Stream *output_stream,
Stream *error_stream,
CommandReturnObject *result)
{
// Don't use m_exe_ctx as this might be called asynchronously
// after the command object DoExecute has finished when doing
// multi-line expression that use an input reader...
ExecutionContext exe_ctx (m_interpreter.GetExecutionContext());
Target *target = exe_ctx.GetTargetPtr();
if (!target)
target = GetDummyTarget();
if (target)
{
lldb::ValueObjectSP result_valobj_sp;
bool keep_in_memory = true;
StackFrame *frame = exe_ctx.GetFramePtr();
EvaluateExpressionOptions options;
options.SetCoerceToId(m_varobj_options.use_objc);
options.SetUnwindOnError(m_command_options.unwind_on_error);
options.SetIgnoreBreakpoints (m_command_options.ignore_breakpoints);
options.SetKeepInMemory(keep_in_memory);
options.SetUseDynamic(m_varobj_options.use_dynamic);
options.SetTryAllThreads(m_command_options.try_all_threads);
options.SetDebug(m_command_options.debug);
options.SetLanguage(m_command_options.language);
options.SetExecutionPolicy(m_command_options.allow_jit ?
EvaluateExpressionOptions::default_execution_policy :
lldb_private::eExecutionPolicyNever);
bool auto_apply_fixits;
if (m_command_options.auto_apply_fixits == eLazyBoolCalculate)
auto_apply_fixits = target->GetEnableAutoApplyFixIts();
else
auto_apply_fixits = m_command_options.auto_apply_fixits == eLazyBoolYes ? true : false;
options.SetAutoApplyFixIts(auto_apply_fixits);
if (m_command_options.top_level)
options.SetExecutionPolicy(eExecutionPolicyTopLevel);
// If there is any chance we are going to stop and want to see
// what went wrong with our expression, we should generate debug info
if (!m_command_options.ignore_breakpoints ||
!m_command_options.unwind_on_error)
options.SetGenerateDebugInfo(true);
if (m_command_options.timeout > 0)
options.SetTimeoutUsec(m_command_options.timeout);
else
options.SetTimeoutUsec(0);
ExpressionResults success = target->EvaluateExpression(expr, frame, result_valobj_sp, options, &m_fixed_expression);
// We only tell you about the FixIt if we applied it. The compiler errors will suggest the FixIt if it parsed.
if (error_stream && !m_fixed_expression.empty() && target->GetEnableNotifyAboutFixIts())
{
if (success == eExpressionCompleted)
error_stream->Printf (" Fix-it applied, fixed expression was: \n %s\n", m_fixed_expression.c_str());
}
if (result_valobj_sp)
{
Format format = m_format_options.GetFormat();
if (result_valobj_sp->GetError().Success())
{
if (format != eFormatVoid)
{
if (format != eFormatDefault)
result_valobj_sp->SetFormat (format);
if (m_varobj_options.elem_count > 0)
{
Error error(CanBeUsedForElementCountPrinting(*result_valobj_sp));
if (error.Fail())
{
result->AppendErrorWithFormat("expression cannot be used with --element-count %s\n", error.AsCString(""));
result->SetStatus(eReturnStatusFailed);
return false;
}
}
DumpValueObjectOptions options(m_varobj_options.GetAsDumpOptions(m_command_options.m_verbosity,format));
options.SetVariableFormatDisplayLanguage(result_valobj_sp->GetPreferredDisplayLanguage());
result_valobj_sp->Dump(*output_stream,options);
if (result)
result->SetStatus (eReturnStatusSuccessFinishResult);
}
}
else
{
if (result_valobj_sp->GetError().GetError() == UserExpression::kNoResult)
{
if (format != eFormatVoid && m_interpreter.GetDebugger().GetNotifyVoid())
{
error_stream->PutCString("(void)\n");
}
if (result)
result->SetStatus (eReturnStatusSuccessFinishResult);
}
else
{
const char *error_cstr = result_valobj_sp->GetError().AsCString();
if (error_cstr && error_cstr[0])
{
const size_t error_cstr_len = strlen (error_cstr);
const bool ends_with_newline = error_cstr[error_cstr_len - 1] == '\n';
if (strstr(error_cstr, "error:") != error_cstr)
error_stream->PutCString ("error: ");
error_stream->Write(error_cstr, error_cstr_len);
if (!ends_with_newline)
error_stream->EOL();
}
else
{
error_stream->PutCString ("error: unknown error\n");
}
if (result)
result->SetStatus (eReturnStatusFailed);
}
}
}
}
else
{
error_stream->Printf ("error: invalid execution context for expression\n");
return false;
}
return true;
}
void
CommandObjectExpression::IOHandlerInputComplete (IOHandler &io_handler, std::string &line)
{
io_handler.SetIsDone(true);
// StreamSP output_stream = io_handler.GetDebugger().GetAsyncOutputStream();
// StreamSP error_stream = io_handler.GetDebugger().GetAsyncErrorStream();
StreamFileSP output_sp(io_handler.GetOutputStreamFile());
StreamFileSP error_sp(io_handler.GetErrorStreamFile());
EvaluateExpression (line.c_str(),
output_sp.get(),
error_sp.get());
if (output_sp)
output_sp->Flush();
if (error_sp)
error_sp->Flush();
}
bool
CommandObjectExpression::IOHandlerIsInputComplete (IOHandler &io_handler,
StringList &lines)
{
// An empty lines is used to indicate the end of input
const size_t num_lines = lines.GetSize();
if (num_lines > 0 && lines[num_lines - 1].empty())
{
// Remove the last empty line from "lines" so it doesn't appear
// in our resulting input and return true to indicate we are done
// getting lines
lines.PopBack();
return true;
}
return false;
}
void
CommandObjectExpression::GetMultilineExpression ()
{
m_expr_lines.clear();
m_expr_line_count = 0;
Debugger &debugger = GetCommandInterpreter().GetDebugger();
bool color_prompt = debugger.GetUseColor();
const bool multiple_lines = true; // Get multiple lines
IOHandlerSP io_handler_sp(new IOHandlerEditline(debugger,
IOHandler::Type::Expression,
"lldb-expr", // Name of input reader for history
nullptr, // No prompt
nullptr, // Continuation prompt
multiple_lines,
color_prompt,
1, // Show line numbers starting at 1
*this));
StreamFileSP output_sp(io_handler_sp->GetOutputStreamFile());
if (output_sp)
{
output_sp->PutCString("Enter expressions, then terminate with an empty line to evaluate:\n");
output_sp->Flush();
}
debugger.PushIOHandler(io_handler_sp);
}
bool
CommandObjectExpression::DoExecute(const char *command,
CommandReturnObject &result)
{
m_fixed_expression.clear();
m_option_group.NotifyOptionParsingStarting();
const char * expr = nullptr;
if (command[0] == '\0')
{
GetMultilineExpression ();
return result.Succeeded();
}
if (command[0] == '-')
{
// We have some options and these options MUST end with --.
const char *end_options = nullptr;
const char *s = command;
while (s && s[0])
{
end_options = ::strstr (s, "--");
if (end_options)
{
end_options += 2; // Get past the "--"
if (::isspace (end_options[0]))
{
expr = end_options;
while (::isspace (*expr))
++expr;
break;
}
}
s = end_options;
}
if (end_options)
{
Args args (llvm::StringRef(command, end_options - command));
if (!ParseOptions (args, result))
return false;
Error error (m_option_group.NotifyOptionParsingFinished());
if (error.Fail())
{
result.AppendError (error.AsCString());
result.SetStatus (eReturnStatusFailed);
return false;
}
if (m_repl_option.GetOptionValue().GetCurrentValue())
{
Target *target = m_interpreter.GetExecutionContext().GetTargetPtr();
if (target)
{
// Drop into REPL
m_expr_lines.clear();
m_expr_line_count = 0;
Debugger &debugger = target->GetDebugger();
// Check if the LLDB command interpreter is sitting on top of a REPL that
// launched it...
if (debugger.CheckTopIOHandlerTypes(IOHandler::Type::CommandInterpreter, IOHandler::Type::REPL))
{
// the LLDB command interpreter is sitting on top of a REPL that launched it,
// so just say the command interpreter is done and fall back to the existing REPL
m_interpreter.GetIOHandler(false)->SetIsDone(true);
}
else
{
// We are launching the REPL on top of the current LLDB command interpreter,
// so just push one
bool initialize = false;
Error repl_error;
REPLSP repl_sp (target->GetREPL(repl_error, m_command_options.language, nullptr, false));
if (!repl_sp)
{
initialize = true;
repl_sp = target->GetREPL(repl_error, m_command_options.language, nullptr, true);
if (!repl_error.Success())
{
result.SetError(repl_error);
return result.Succeeded();
}
}
if (repl_sp)
{
if (initialize)
{
repl_sp->SetCommandOptions(m_command_options);
repl_sp->SetFormatOptions(m_format_options);
repl_sp->SetValueObjectDisplayOptions(m_varobj_options);
}
IOHandlerSP io_handler_sp (repl_sp->GetIOHandler());
io_handler_sp->SetIsDone(false);
debugger.PushIOHandler(io_handler_sp);
}
else
{
repl_error.SetErrorStringWithFormat("Couldn't create a REPL for %s", Language::GetNameForLanguageType(m_command_options.language));
result.SetError(repl_error);
return result.Succeeded();
}
}
}
}
// No expression following options
else if (expr == nullptr || expr[0] == '\0')
{
GetMultilineExpression ();
return result.Succeeded();
}
}
}
if (expr == nullptr)
expr = command;
if (EvaluateExpression (expr, &(result.GetOutputStream()), &(result.GetErrorStream()), &result))
{
Target *target = m_interpreter.GetExecutionContext().GetTargetPtr();
if (!m_fixed_expression.empty() && target->GetEnableNotifyAboutFixIts())
{
CommandHistory &history = m_interpreter.GetCommandHistory();
// FIXME: Can we figure out what the user actually typed (e.g. some alias for expr???)
// If we can it would be nice to show that.
std::string fixed_command("expression ");
if (expr == command)
fixed_command.append(m_fixed_expression);
else
{
// Add in any options that might have been in the original command:
fixed_command.append(command, expr - command);
fixed_command.append(m_fixed_expression);
}
history.AppendString(fixed_command);
}
return true;
}
result.SetStatus (eReturnStatusFailed);
return false;
}