//===-- CommandObjectWatchpointCommand.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 #include // Other libraries and framework includes // Project includes #include "CommandObjectWatchpointCommand.h" #include "CommandObjectWatchpoint.h" #include "lldb/Core/IOHandler.h" #include "lldb/Interpreter/CommandInterpreter.h" #include "lldb/Interpreter/CommandReturnObject.h" #include "lldb/Target/Target.h" #include "lldb/Target/Thread.h" #include "lldb/Breakpoint/Watchpoint.h" #include "lldb/Breakpoint/StoppointCallbackContext.h" #include "lldb/Core/State.h" using namespace lldb; using namespace lldb_private; //------------------------------------------------------------------------- // CommandObjectWatchpointCommandAdd //------------------------------------------------------------------------- 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), IOHandlerDelegateMultiline("DONE", IOHandlerDelegate::Completion::LLDBCommand), m_options(interpreter) { 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) override { StreamFileSP output_sp(io_handler.GetOutputStreamFile()); if (output_sp) { 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 data_ap(new WatchpointOptions::CommandData()); if (data_ap) { data_ap->user_source.SplitIntoLines(line); BatonSP baton_sp (new WatchpointOptions::CommandBaton (data_ap.release())); wp_options->SetCallback (WatchpointOptionsCallbackFunction, baton_sp); } } } void CollectDataForWatchpointCommandCallback (WatchpointOptions *wp_options, CommandReturnObject &result) { m_interpreter.GetLLDBCommandsFromIOHandler ("> ", // Prompt *this, // IOHandlerDelegate true, // Run IOHandler in async mode 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 data_ap(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_ap->user_source.AppendString (oneliner); data_ap->script_source.assign (oneliner); data_ap->stop_on_error = m_options.m_stop_on_error; BatonSP baton_sp (new WatchpointOptions::CommandBaton (data_ap.release())); 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.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 (CommandInterpreter &interpreter) : Options (interpreter), 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; Error SetOptionValue (uint32_t option_idx, const char *option_arg) override { Error error; const int short_option = m_getopt_table[option_idx].val; switch (short_option) { case 'o': m_use_one_liner = true; m_one_liner = option_arg; break; case 's': m_script_language = (lldb::ScriptLanguage) Args::StringToOptionEnum (option_arg, g_option_table[option_idx].enum_values, eScriptLanguageNone, error); m_use_script_language = (m_script_language == eScriptLanguagePython || m_script_language == eScriptLanguageDefault); break; case 'e': { bool success = false; m_stop_on_error = Args::StringToBoolean(option_arg, false, &success); if (!success) error.SetErrorStringWithFormat("invalid value for stop-on-error: \"%s\"", option_arg); } break; case 'F': m_use_one_liner = false; m_use_script_language = true; m_function_name.assign(option_arg); break; default: break; } return error; } void OptionParsingStarting () 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(); } const OptionDefinition* GetDefinitions () override { return g_option_table; } // Options table: Required for subclasses of Options. static OptionDefinition g_option_table[]; // 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 = m_interpreter.GetDebugger().GetSelectedTarget().get(); if (target == nullptr) { result.AppendError ("There is not a current executable; there are no watchpoints to which to add commands"); result.SetStatus (eReturnStatusFailed); return false; } 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_use_script_language && !m_options.m_function_name.empty()) { result.AppendError ("need to enable scripting to have a function run as a watchpoint command"); result.SetStatus (eReturnStatusFailed); return false; } std::vector 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) { // Special handling for one-liner specified inline. if (m_options.m_use_one_liner) { m_interpreter.GetScriptInterpreter()->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)"; m_interpreter.GetScriptInterpreter()->SetWatchpointCommandCallback (wp_options, oneliner.c_str()); } else { m_interpreter.GetScriptInterpreter()->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; }; // 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 OptionEnumValueElement g_script_option_enumeration[4] = { { eScriptLanguageNone, "command", "Commands are in the lldb command interpreter language"}, { eScriptLanguagePython, "python", "Commands are in the Python language."}, { eSortOrderByName, "default-script", "Commands are in the default scripting language."}, { 0, nullptr, nullptr } }; OptionDefinition CommandObjectWatchpointCommandAdd::CommandOptions::g_option_table[] = { { LLDB_OPT_SET_1, false, "one-liner", 'o', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeOneLiner, "Specify a one-line watchpoint command inline. Be sure to surround it with quotes." }, { LLDB_OPT_SET_ALL, false, "stop-on-error", 'e', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypeBoolean, "Specify whether watchpoint command execution should terminate on error." }, { LLDB_OPT_SET_ALL, false, "script-type", 's', OptionParser::eRequiredArgument, nullptr, g_script_option_enumeration, 0, eArgTypeNone, "Specify the language for the commands - if none is specified, the lldb command interpreter will be used."}, { LLDB_OPT_SET_2, false, "python-function", 'F', OptionParser::eRequiredArgument, nullptr, nullptr, 0, eArgTypePythonFunction, "Give the name of a Python function to run as command for this watchpoint. Be sure to give a module name if appropriate."}, { 0, false, nullptr, 0, 0, nullptr, nullptr, 0, eArgTypeNone, nullptr } }; //------------------------------------------------------------------------- // CommandObjectWatchpointCommandDelete //------------------------------------------------------------------------- class CommandObjectWatchpointCommandDelete : public CommandObjectParsed { public: CommandObjectWatchpointCommandDelete (CommandInterpreter &interpreter) : CommandObjectParsed(interpreter, "delete", "Delete the set of commands from a watchpoint.", nullptr) { 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 = m_interpreter.GetDebugger().GetSelectedTarget().get(); if (target == nullptr) { result.AppendError ("There is not a current executable; there are no watchpoints from which to delete commands"); result.SetStatus (eReturnStatusFailed); return false; } 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 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) { 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 = m_interpreter.GetDebugger().GetSelectedTarget().get(); if (target == nullptr) { result.AppendError ("There is not a current executable; there are no watchpoints for which to list commands"); result.SetStatus (eReturnStatusFailed); return false; } 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 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); result.GetOutputStream().IndentMore (); baton->GetDescription(&result.GetOutputStream(), eDescriptionLevelFull); result.GetOutputStream().IndentLess (); } 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 'commmands').", "command [] ") { 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;