llvm-project/lldb/source/Commands/CommandObjectWatchpointComm...

672 lines
24 KiB
C++

//===-- CommandObjectWatchpointCommand.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 <vector>
#include "CommandObjectWatchpoint.h"
#include "CommandObjectWatchpointCommand.h"
#include "lldb/Breakpoint/StoppointCallbackContext.h"
#include "lldb/Breakpoint/Watchpoint.h"
#include "lldb/Core/IOHandler.h"
#include "lldb/Host/OptionParser.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Interpreter/OptionArgParser.h"
#include "lldb/Target/Target.h"
using namespace lldb;
using namespace lldb_private;
// FIXME: "script-type" needs to have its contents determined dynamically, so
// somebody can add a new scripting language to lldb and have it pickable here
// without having to change this enumeration by hand and rebuild lldb proper.
static constexpr OptionEnumValueElement g_script_option_enumeration[] = {
{
eScriptLanguageNone,
"command",
"Commands are in the lldb command interpreter language",
},
{
eScriptLanguagePython,
"python",
"Commands are in the Python language.",
},
{
eScriptLanguageLua,
"lua",
"Commands are in the Lua language.",
},
{
eSortOrderByName,
"default-script",
"Commands are in the default scripting language.",
},
};
static constexpr OptionEnumValues ScriptOptionEnum() {
return OptionEnumValues(g_script_option_enumeration);
}
#define LLDB_OPTIONS_watchpoint_command_add
#include "CommandOptions.inc"
class CommandObjectWatchpointCommandAdd : public CommandObjectParsed,
public IOHandlerDelegateMultiline {
public:
CommandObjectWatchpointCommandAdd(CommandInterpreter &interpreter)
: CommandObjectParsed(interpreter, "add",
"Add a set of LLDB commands to a watchpoint, to be "
"executed whenever the watchpoint is hit.",
nullptr, eCommandRequiresTarget),
IOHandlerDelegateMultiline("DONE",
IOHandlerDelegate::Completion::LLDBCommand),
m_options() {
SetHelpLong(
R"(
General information about entering watchpoint commands
------------------------------------------------------
)"
"This command will prompt for commands to be executed when the specified \
watchpoint is hit. Each command is typed on its own line following the '> ' \
prompt until 'DONE' is entered."
R"(
)"
"Syntactic errors may not be detected when initially entered, and many \
malformed commands can silently fail when executed. If your watchpoint commands \
do not appear to be executing, double-check the command syntax."
R"(
)"
"Note: You may enter any debugger command exactly as you would at the debugger \
prompt. There is no limit to the number of commands supplied, but do NOT enter \
more than one command per line."
R"(
Special information about PYTHON watchpoint commands
----------------------------------------------------
)"
"You may enter either one or more lines of Python, including function \
definitions or calls to functions that will have been imported by the time \
the code executes. Single line watchpoint commands will be interpreted 'as is' \
when the watchpoint is hit. Multiple lines of Python will be wrapped in a \
generated function, and a call to the function will be attached to the watchpoint."
R"(
This auto-generated function is passed in three arguments:
frame: an lldb.SBFrame object for the frame which hit the watchpoint.
wp: the watchpoint that was hit.
)"
"When specifying a python function with the --python-function option, you need \
to supply the function name prepended by the module name:"
R"(
--python-function myutils.watchpoint_callback
The function itself must have the following prototype:
def watchpoint_callback(frame, wp):
# Your code goes here
)"
"The arguments are the same as the arguments passed to generated functions as \
described above. Note that the global variable 'lldb.frame' will NOT be updated when \
this function is called, so be sure to use the 'frame' argument. The 'frame' argument \
can get you to the thread via frame.GetThread(), the thread can get you to the \
process via thread.GetProcess(), and the process can get you back to the target \
via process.GetTarget()."
R"(
)"
"Important Note: As Python code gets collected into functions, access to global \
variables requires explicit scoping using the 'global' keyword. Be sure to use correct \
Python syntax, including indentation, when entering Python watchpoint commands."
R"(
Example Python one-line watchpoint command:
(lldb) watchpoint command add -s python 1
Enter your Python command(s). Type 'DONE' to end.
> print "Hit this watchpoint!"
> DONE
As a convenience, this also works for a short Python one-liner:
(lldb) watchpoint command add -s python 1 -o 'import time; print time.asctime()'
(lldb) run
Launching '.../a.out' (x86_64)
(lldb) Fri Sep 10 12:17:45 2010
Process 21778 Stopped
* thread #1: tid = 0x2e03, 0x0000000100000de8 a.out`c + 7 at main.c:39, stop reason = watchpoint 1.1, queue = com.apple.main-thread
36
37 int c(int val)
38 {
39 -> return val + 3;
40 }
41
42 int main (int argc, char const *argv[])
Example multiple line Python watchpoint command, using function definition:
(lldb) watchpoint command add -s python 1
Enter your Python command(s). Type 'DONE' to end.
> def watchpoint_output (wp_no):
> out_string = "Hit watchpoint number " + repr (wp_no)
> print out_string
> return True
> watchpoint_output (1)
> DONE
Example multiple line Python watchpoint command, using 'loose' Python:
(lldb) watchpoint command add -s p 1
Enter your Python command(s). Type 'DONE' to end.
> global wp_count
> wp_count = wp_count + 1
> print "Hit this watchpoint " + repr(wp_count) + " times!"
> DONE
)"
"In this case, since there is a reference to a global variable, \
'wp_count', you will also need to make sure 'wp_count' exists and is \
initialized:"
R"(
(lldb) script
>>> wp_count = 0
>>> quit()
)"
"Final Note: A warning that no watchpoint command was generated when there \
are no syntax errors may indicate that a function was declared but never called.");
CommandArgumentEntry arg;
CommandArgumentData wp_id_arg;
// Define the first (and only) variant of this arg.
wp_id_arg.arg_type = eArgTypeWatchpointID;
wp_id_arg.arg_repetition = eArgRepeatPlain;
// There is only one variant this argument could be; put it into the
// argument entry.
arg.push_back(wp_id_arg);
// Push the data for the first argument into the m_arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectWatchpointCommandAdd() override = default;
Options *GetOptions() override { return &m_options; }
void IOHandlerActivated(IOHandler &io_handler, bool interactive) override {
StreamFileSP output_sp(io_handler.GetOutputStreamFileSP());
if (output_sp && interactive) {
output_sp->PutCString(
"Enter your debugger command(s). Type 'DONE' to end.\n");
output_sp->Flush();
}
}
void IOHandlerInputComplete(IOHandler &io_handler,
std::string &line) override {
io_handler.SetIsDone(true);
// The WatchpointOptions object is owned by the watchpoint or watchpoint
// location
WatchpointOptions *wp_options =
(WatchpointOptions *)io_handler.GetUserData();
if (wp_options) {
std::unique_ptr<WatchpointOptions::CommandData> data_up(
new WatchpointOptions::CommandData());
if (data_up) {
data_up->user_source.SplitIntoLines(line);
auto baton_sp = std::make_shared<WatchpointOptions::CommandBaton>(
std::move(data_up));
wp_options->SetCallback(WatchpointOptionsCallbackFunction, baton_sp);
}
}
}
void CollectDataForWatchpointCommandCallback(WatchpointOptions *wp_options,
CommandReturnObject &result) {
m_interpreter.GetLLDBCommandsFromIOHandler(
"> ", // Prompt
*this, // IOHandlerDelegate
wp_options); // Baton for the "io_handler" that will be passed back into
// our IOHandlerDelegate functions
}
/// Set a one-liner as the callback for the watchpoint.
void SetWatchpointCommandCallback(WatchpointOptions *wp_options,
const char *oneliner) {
std::unique_ptr<WatchpointOptions::CommandData> data_up(
new WatchpointOptions::CommandData());
// It's necessary to set both user_source and script_source to the
// oneliner. The former is used to generate callback description (as in
// watchpoint command list) while the latter is used for Python to
// interpret during the actual callback.
data_up->user_source.AppendString(oneliner);
data_up->script_source.assign(oneliner);
data_up->stop_on_error = m_options.m_stop_on_error;
auto baton_sp =
std::make_shared<WatchpointOptions::CommandBaton>(std::move(data_up));
wp_options->SetCallback(WatchpointOptionsCallbackFunction, baton_sp);
}
static bool
WatchpointOptionsCallbackFunction(void *baton,
StoppointCallbackContext *context,
lldb::user_id_t watch_id) {
bool ret_value = true;
if (baton == nullptr)
return true;
WatchpointOptions::CommandData *data =
(WatchpointOptions::CommandData *)baton;
StringList &commands = data->user_source;
if (commands.GetSize() > 0) {
ExecutionContext exe_ctx(context->exe_ctx_ref);
Target *target = exe_ctx.GetTargetPtr();
if (target) {
CommandReturnObject result;
Debugger &debugger = target->GetDebugger();
// Rig up the results secondary output stream to the debugger's, so the
// output will come out synchronously if the debugger is set up that
// way.
StreamSP output_stream(debugger.GetAsyncOutputStream());
StreamSP error_stream(debugger.GetAsyncErrorStream());
result.SetImmediateOutputStream(output_stream);
result.SetImmediateErrorStream(error_stream);
CommandInterpreterRunOptions options;
options.SetStopOnContinue(true);
options.SetStopOnError(data->stop_on_error);
options.SetEchoCommands(false);
options.SetPrintResults(true);
options.SetPrintErrors(true);
options.SetAddToHistory(false);
debugger.GetCommandInterpreter().HandleCommands(commands, &exe_ctx,
options, result);
result.GetImmediateOutputStream()->Flush();
result.GetImmediateErrorStream()->Flush();
}
}
return ret_value;
}
class CommandOptions : public Options {
public:
CommandOptions()
: Options(), m_use_commands(false), m_use_script_language(false),
m_script_language(eScriptLanguageNone), m_use_one_liner(false),
m_one_liner(), m_function_name() {}
~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 'o':
m_use_one_liner = true;
m_one_liner = std::string(option_arg);
break;
case 's':
m_script_language = (lldb::ScriptLanguage)OptionArgParser::ToOptionEnum(
option_arg, GetDefinitions()[option_idx].enum_values,
eScriptLanguageNone, error);
switch (m_script_language) {
case eScriptLanguagePython:
case eScriptLanguageLua:
m_use_script_language = true;
break;
case eScriptLanguageNone:
case eScriptLanguageUnknown:
m_use_script_language = false;
break;
}
break;
case 'e': {
bool success = false;
m_stop_on_error =
OptionArgParser::ToBoolean(option_arg, false, &success);
if (!success)
error.SetErrorStringWithFormat(
"invalid value for stop-on-error: \"%s\"",
option_arg.str().c_str());
} break;
case 'F':
m_use_one_liner = false;
m_function_name.assign(std::string(option_arg));
break;
default:
llvm_unreachable("Unimplemented option");
}
return error;
}
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_use_commands = true;
m_use_script_language = false;
m_script_language = eScriptLanguageNone;
m_use_one_liner = false;
m_stop_on_error = true;
m_one_liner.clear();
m_function_name.clear();
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::makeArrayRef(g_watchpoint_command_add_options);
}
// Instance variables to hold the values for command options.
bool m_use_commands;
bool m_use_script_language;
lldb::ScriptLanguage m_script_language;
// Instance variables to hold the values for one_liner options.
bool m_use_one_liner;
std::string m_one_liner;
bool m_stop_on_error;
std::string m_function_name;
};
protected:
bool DoExecute(Args &command, CommandReturnObject &result) override {
Target *target = &GetSelectedTarget();
const WatchpointList &watchpoints = target->GetWatchpointList();
size_t num_watchpoints = watchpoints.GetSize();
if (num_watchpoints == 0) {
result.AppendError("No watchpoints exist to have commands added");
result.SetStatus(eReturnStatusFailed);
return false;
}
if (!m_options.m_function_name.empty()) {
if (!m_options.m_use_script_language) {
m_options.m_script_language = GetDebugger().GetScriptLanguage();
m_options.m_use_script_language = true;
}
}
std::vector<uint32_t> valid_wp_ids;
if (!CommandObjectMultiwordWatchpoint::VerifyWatchpointIDs(target, command,
valid_wp_ids)) {
result.AppendError("Invalid watchpoints specification.");
result.SetStatus(eReturnStatusFailed);
return false;
}
result.SetStatus(eReturnStatusSuccessFinishNoResult);
const size_t count = valid_wp_ids.size();
for (size_t i = 0; i < count; ++i) {
uint32_t cur_wp_id = valid_wp_ids.at(i);
if (cur_wp_id != LLDB_INVALID_WATCH_ID) {
Watchpoint *wp = target->GetWatchpointList().FindByID(cur_wp_id).get();
// Sanity check wp first.
if (wp == nullptr)
continue;
WatchpointOptions *wp_options = wp->GetOptions();
// Skip this watchpoint if wp_options is not good.
if (wp_options == nullptr)
continue;
// If we are using script language, get the script interpreter in order
// to set or collect command callback. Otherwise, call the methods
// associated with this object.
if (m_options.m_use_script_language) {
ScriptInterpreter *script_interp = GetDebugger().GetScriptInterpreter(
/*can_create=*/true, m_options.m_script_language);
// Special handling for one-liner specified inline.
if (m_options.m_use_one_liner) {
script_interp->SetWatchpointCommandCallback(
wp_options, m_options.m_one_liner.c_str());
}
// Special handling for using a Python function by name instead of
// extending the watchpoint callback data structures, we just
// automatize what the user would do manually: make their watchpoint
// command be a function call
else if (!m_options.m_function_name.empty()) {
std::string oneliner(m_options.m_function_name);
oneliner += "(frame, wp, internal_dict)";
script_interp->SetWatchpointCommandCallback(
wp_options, oneliner.c_str());
} else {
script_interp->CollectDataForWatchpointCommandCallback(wp_options,
result);
}
} else {
// Special handling for one-liner specified inline.
if (m_options.m_use_one_liner)
SetWatchpointCommandCallback(wp_options,
m_options.m_one_liner.c_str());
else
CollectDataForWatchpointCommandCallback(wp_options, result);
}
}
}
return result.Succeeded();
}
private:
CommandOptions m_options;
};
// CommandObjectWatchpointCommandDelete
class CommandObjectWatchpointCommandDelete : public CommandObjectParsed {
public:
CommandObjectWatchpointCommandDelete(CommandInterpreter &interpreter)
: CommandObjectParsed(interpreter, "delete",
"Delete the set of commands from a watchpoint.",
nullptr, eCommandRequiresTarget) {
CommandArgumentEntry arg;
CommandArgumentData wp_id_arg;
// Define the first (and only) variant of this arg.
wp_id_arg.arg_type = eArgTypeWatchpointID;
wp_id_arg.arg_repetition = eArgRepeatPlain;
// There is only one variant this argument could be; put it into the
// argument entry.
arg.push_back(wp_id_arg);
// Push the data for the first argument into the m_arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectWatchpointCommandDelete() override = default;
protected:
bool DoExecute(Args &command, CommandReturnObject &result) override {
Target *target = &GetSelectedTarget();
const WatchpointList &watchpoints = target->GetWatchpointList();
size_t num_watchpoints = watchpoints.GetSize();
if (num_watchpoints == 0) {
result.AppendError("No watchpoints exist to have commands deleted");
result.SetStatus(eReturnStatusFailed);
return false;
}
if (command.GetArgumentCount() == 0) {
result.AppendError(
"No watchpoint specified from which to delete the commands");
result.SetStatus(eReturnStatusFailed);
return false;
}
std::vector<uint32_t> valid_wp_ids;
if (!CommandObjectMultiwordWatchpoint::VerifyWatchpointIDs(target, command,
valid_wp_ids)) {
result.AppendError("Invalid watchpoints specification.");
result.SetStatus(eReturnStatusFailed);
return false;
}
result.SetStatus(eReturnStatusSuccessFinishNoResult);
const size_t count = valid_wp_ids.size();
for (size_t i = 0; i < count; ++i) {
uint32_t cur_wp_id = valid_wp_ids.at(i);
if (cur_wp_id != LLDB_INVALID_WATCH_ID) {
Watchpoint *wp = target->GetWatchpointList().FindByID(cur_wp_id).get();
if (wp)
wp->ClearCallback();
} else {
result.AppendErrorWithFormat("Invalid watchpoint ID: %u.\n", cur_wp_id);
result.SetStatus(eReturnStatusFailed);
return false;
}
}
return result.Succeeded();
}
};
// CommandObjectWatchpointCommandList
class CommandObjectWatchpointCommandList : public CommandObjectParsed {
public:
CommandObjectWatchpointCommandList(CommandInterpreter &interpreter)
: CommandObjectParsed(interpreter, "list",
"List the script or set of commands to be executed "
"when the watchpoint is hit.",
nullptr, eCommandRequiresTarget) {
CommandArgumentEntry arg;
CommandArgumentData wp_id_arg;
// Define the first (and only) variant of this arg.
wp_id_arg.arg_type = eArgTypeWatchpointID;
wp_id_arg.arg_repetition = eArgRepeatPlain;
// There is only one variant this argument could be; put it into the
// argument entry.
arg.push_back(wp_id_arg);
// Push the data for the first argument into the m_arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectWatchpointCommandList() override = default;
protected:
bool DoExecute(Args &command, CommandReturnObject &result) override {
Target *target = &GetSelectedTarget();
const WatchpointList &watchpoints = target->GetWatchpointList();
size_t num_watchpoints = watchpoints.GetSize();
if (num_watchpoints == 0) {
result.AppendError("No watchpoints exist for which to list commands");
result.SetStatus(eReturnStatusFailed);
return false;
}
if (command.GetArgumentCount() == 0) {
result.AppendError(
"No watchpoint specified for which to list the commands");
result.SetStatus(eReturnStatusFailed);
return false;
}
std::vector<uint32_t> valid_wp_ids;
if (!CommandObjectMultiwordWatchpoint::VerifyWatchpointIDs(target, command,
valid_wp_ids)) {
result.AppendError("Invalid watchpoints specification.");
result.SetStatus(eReturnStatusFailed);
return false;
}
result.SetStatus(eReturnStatusSuccessFinishNoResult);
const size_t count = valid_wp_ids.size();
for (size_t i = 0; i < count; ++i) {
uint32_t cur_wp_id = valid_wp_ids.at(i);
if (cur_wp_id != LLDB_INVALID_WATCH_ID) {
Watchpoint *wp = target->GetWatchpointList().FindByID(cur_wp_id).get();
if (wp) {
const WatchpointOptions *wp_options = wp->GetOptions();
if (wp_options) {
// Get the callback baton associated with the current watchpoint.
const Baton *baton = wp_options->GetBaton();
if (baton) {
result.GetOutputStream().Printf("Watchpoint %u:\n", cur_wp_id);
baton->GetDescription(result.GetOutputStream().AsRawOstream(),
eDescriptionLevelFull,
result.GetOutputStream().GetIndentLevel() +
2);
} else {
result.AppendMessageWithFormat(
"Watchpoint %u does not have an associated command.\n",
cur_wp_id);
}
}
result.SetStatus(eReturnStatusSuccessFinishResult);
} else {
result.AppendErrorWithFormat("Invalid watchpoint ID: %u.\n",
cur_wp_id);
result.SetStatus(eReturnStatusFailed);
}
}
}
return result.Succeeded();
}
};
// CommandObjectWatchpointCommand
CommandObjectWatchpointCommand::CommandObjectWatchpointCommand(
CommandInterpreter &interpreter)
: CommandObjectMultiword(
interpreter, "command",
"Commands for adding, removing and examining LLDB commands "
"executed when the watchpoint is hit (watchpoint 'commands').",
"command <sub-command> [<sub-command-options>] <watchpoint-id>") {
CommandObjectSP add_command_object(
new CommandObjectWatchpointCommandAdd(interpreter));
CommandObjectSP delete_command_object(
new CommandObjectWatchpointCommandDelete(interpreter));
CommandObjectSP list_command_object(
new CommandObjectWatchpointCommandList(interpreter));
add_command_object->SetCommandName("watchpoint command add");
delete_command_object->SetCommandName("watchpoint command delete");
list_command_object->SetCommandName("watchpoint command list");
LoadSubCommand("add", add_command_object);
LoadSubCommand("delete", delete_command_object);
LoadSubCommand("list", list_command_object);
}
CommandObjectWatchpointCommand::~CommandObjectWatchpointCommand() = default;