//===-- CommandObjectBreakpointCommand.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 "CommandObjectBreakpointCommand.h" #include "CommandObjectBreakpoint.h" #include "lldb/Breakpoint/Breakpoint.h" #include "lldb/Breakpoint/BreakpointIDList.h" #include "lldb/Breakpoint/BreakpointLocation.h" #include "lldb/Core/IOHandler.h" #include "lldb/Host/OptionParser.h" #include "lldb/Interpreter/CommandInterpreter.h" #include "lldb/Interpreter/CommandOptionArgumentTable.h" #include "lldb/Interpreter/CommandReturnObject.h" #include "lldb/Interpreter/OptionArgParser.h" #include "lldb/Interpreter/OptionGroupPythonClassWithDict.h" #include "lldb/Target/Target.h" using namespace lldb; using namespace lldb_private; #define LLDB_OPTIONS_breakpoint_command_add #include "CommandOptions.inc" class CommandObjectBreakpointCommandAdd : public CommandObjectParsed, public IOHandlerDelegateMultiline { public: CommandObjectBreakpointCommandAdd(CommandInterpreter &interpreter) : CommandObjectParsed(interpreter, "add", "Add LLDB commands to a breakpoint, to be executed " "whenever the breakpoint is hit. " "The commands added to the breakpoint replace any " "commands previously added to it." " If no breakpoint is specified, adds the " "commands to the last created breakpoint.", nullptr), IOHandlerDelegateMultiline("DONE", IOHandlerDelegate::Completion::LLDBCommand), m_func_options("breakpoint command", false, 'F') { SetHelpLong( R"( General information about entering breakpoint commands ------------------------------------------------------ )" "This command will prompt for commands to be executed when the specified \ breakpoint 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 breakpoint 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 breakpoint 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 breakpoint commands will be interpreted 'as is' \ when the breakpoint is hit. Multiple lines of Python will be wrapped in a \ generated function, and a call to the function will be attached to the breakpoint." R"( This auto-generated function is passed in three arguments: frame: an lldb.SBFrame object for the frame which hit breakpoint. bp_loc: an lldb.SBBreakpointLocation object that represents the breakpoint location that was hit. dict: the python session dictionary 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.breakpoint_callback The function itself must have either of the following prototypes: def breakpoint_callback(frame, bp_loc, internal_dict): # Your code goes here or: def breakpoint_callback(frame, bp_loc, extra_args, internal_dict): # Your code goes here )" "The arguments are the same as the arguments passed to generated functions as \ described above. In the second form, any -k and -v pairs provided to the command will \ be packaged into a SBDictionary in an SBStructuredData and passed as the extra_args parameter. \ \n\n\ 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 breakpoint commands." R"( Example Python one-line breakpoint command: (lldb) breakpoint command add -s python 1 Enter your Python command(s). Type 'DONE' to end. def function (frame, bp_loc, internal_dict): """frame: the lldb.SBFrame for the location at which you stopped bp_loc: an lldb.SBBreakpointLocation for the breakpoint location information internal_dict: an LLDB support object not to be used""" print("Hit this breakpoint!") DONE As a convenience, this also works for a short Python one-liner: (lldb) breakpoint 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 = breakpoint 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 breakpoint command: (lldb) breakpoint command add -s p 1 Enter your Python command(s). Type 'DONE' to end. def function (frame, bp_loc, internal_dict): """frame: the lldb.SBFrame for the location at which you stopped bp_loc: an lldb.SBBreakpointLocation for the breakpoint location information internal_dict: an LLDB support object not to be used""" global bp_count bp_count = bp_count + 1 print("Hit this breakpoint " + repr(bp_count) + " times!") DONE )" "In this case, since there is a reference to a global variable, \ 'bp_count', you will also need to make sure 'bp_count' exists and is \ initialized:" R"( (lldb) script >>> bp_count = 0 >>> quit() )" "Your Python code, however organized, can optionally return a value. \ If the returned value is False, that tells LLDB not to stop at the breakpoint \ to which the code is associated. Returning anything other than False, or even \ returning None, or even omitting a return statement entirely, will cause \ LLDB to stop." R"( )" "Final Note: A warning that no breakpoint command was generated when there \ are no syntax errors may indicate that a function was declared but never called."); m_all_options.Append(&m_options); m_all_options.Append(&m_func_options, LLDB_OPT_SET_2 | LLDB_OPT_SET_3, LLDB_OPT_SET_2); m_all_options.Finalize(); AddSimpleArgumentList(eArgTypeBreakpointID, eArgRepeatOptional); } ~CommandObjectBreakpointCommandAdd() override = default; Options *GetOptions() override { return &m_all_options; } void IOHandlerActivated(IOHandler &io_handler, bool interactive) override { StreamFileSP output_sp(io_handler.GetOutputStreamFileSP()); if (output_sp && interactive) { output_sp->PutCString(g_reader_instructions); output_sp->Flush(); } } void IOHandlerInputComplete(IOHandler &io_handler, std::string &line) override { io_handler.SetIsDone(true); std::vector> *bp_options_vec = (std::vector> *) io_handler.GetUserData(); for (BreakpointOptions &bp_options : *bp_options_vec) { auto cmd_data = std::make_unique(); cmd_data->user_source.SplitIntoLines(line.c_str(), line.size()); bp_options.SetCommandDataCallback(cmd_data); } } void CollectDataForBreakpointCommandCallback( std::vector> &bp_options_vec, CommandReturnObject &result) { m_interpreter.GetLLDBCommandsFromIOHandler( "> ", // Prompt *this, // IOHandlerDelegate &bp_options_vec); // Baton for the "io_handler" that will be passed back // into our IOHandlerDelegate functions } /// Set a one-liner as the callback for the breakpoint. void SetBreakpointCommandCallback( std::vector> &bp_options_vec, const char *oneliner) { for (BreakpointOptions &bp_options : bp_options_vec) { auto cmd_data = std::make_unique(); cmd_data->user_source.AppendString(oneliner); cmd_data->stop_on_error = m_options.m_stop_on_error; bp_options.SetCommandDataCallback(cmd_data); } } class CommandOptions : public OptionGroup { public: CommandOptions() = default; ~CommandOptions() override = default; Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg, ExecutionContext *execution_context) override { Status error; const int short_option = g_breakpoint_command_add_options[option_idx].short_option; 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, g_breakpoint_command_add_options[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 'D': m_use_dummy = true; 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_use_dummy = false; } llvm::ArrayRef GetDefinitions() override { return llvm::ArrayRef(g_breakpoint_command_add_options); } // Instance variables to hold the values for command options. bool m_use_commands = false; bool m_use_script_language = false; lldb::ScriptLanguage m_script_language = eScriptLanguageNone; // Instance variables to hold the values for one_liner options. bool m_use_one_liner = false; std::string m_one_liner; bool m_stop_on_error; bool m_use_dummy; }; protected: void DoExecute(Args &command, CommandReturnObject &result) override { Target &target = GetSelectedOrDummyTarget(m_options.m_use_dummy); const BreakpointList &breakpoints = target.GetBreakpointList(); size_t num_breakpoints = breakpoints.GetSize(); if (num_breakpoints == 0) { result.AppendError("No breakpoints exist to have commands added"); return; } if (!m_func_options.GetName().empty()) { m_options.m_use_one_liner = false; if (!m_options.m_use_script_language) { m_options.m_script_language = GetDebugger().GetScriptLanguage(); m_options.m_use_script_language = true; } } BreakpointIDList valid_bp_ids; CommandObjectMultiwordBreakpoint::VerifyBreakpointOrLocationIDs( command, &target, result, &valid_bp_ids, BreakpointName::Permissions::PermissionKinds::listPerm); m_bp_options_vec.clear(); if (result.Succeeded()) { const size_t count = valid_bp_ids.GetSize(); for (size_t i = 0; i < count; ++i) { BreakpointID cur_bp_id = valid_bp_ids.GetBreakpointIDAtIndex(i); if (cur_bp_id.GetBreakpointID() != LLDB_INVALID_BREAK_ID) { Breakpoint *bp = target.GetBreakpointByID(cur_bp_id.GetBreakpointID()).get(); if (cur_bp_id.GetLocationID() == LLDB_INVALID_BREAK_ID) { // This breakpoint does not have an associated location. m_bp_options_vec.push_back(bp->GetOptions()); } else { BreakpointLocationSP bp_loc_sp( bp->FindLocationByID(cur_bp_id.GetLocationID())); // This breakpoint does have an associated location. Get its // breakpoint options. if (bp_loc_sp) m_bp_options_vec.push_back(bp_loc_sp->GetLocationOptions()); } } } // 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) { Status error; 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) { error = script_interp->SetBreakpointCommandCallback( m_bp_options_vec, m_options.m_one_liner.c_str()); } else if (!m_func_options.GetName().empty()) { error = script_interp->SetBreakpointCommandCallbackFunction( m_bp_options_vec, m_func_options.GetName().c_str(), m_func_options.GetStructuredData()); } else { script_interp->CollectDataForBreakpointCommandCallback( m_bp_options_vec, result); } if (!error.Success()) result.SetError(error); } else { // Special handling for one-liner specified inline. if (m_options.m_use_one_liner) SetBreakpointCommandCallback(m_bp_options_vec, m_options.m_one_liner.c_str()); else CollectDataForBreakpointCommandCallback(m_bp_options_vec, result); } } } private: CommandOptions m_options; OptionGroupPythonClassWithDict m_func_options; OptionGroupOptions m_all_options; std::vector> m_bp_options_vec; // This stores the // breakpoint options that // we are currently // collecting commands for. In the CollectData... calls we need to hand this // off to the IOHandler, which may run asynchronously. So we have to have // some way to keep it alive, and not leak it. Making it an ivar of the // command object, which never goes away achieves this. Note that if we were // able to run the same command concurrently in one interpreter we'd have to // make this "per invocation". But there are many more reasons why it is not // in general safe to do that in lldb at present, so it isn't worthwhile to // come up with a more complex mechanism to address this particular weakness // right now. static const char *g_reader_instructions; }; const char *CommandObjectBreakpointCommandAdd::g_reader_instructions = "Enter your debugger command(s). Type 'DONE' to end.\n"; // CommandObjectBreakpointCommandDelete #define LLDB_OPTIONS_breakpoint_command_delete #include "CommandOptions.inc" class CommandObjectBreakpointCommandDelete : public CommandObjectParsed { public: CommandObjectBreakpointCommandDelete(CommandInterpreter &interpreter) : CommandObjectParsed(interpreter, "delete", "Delete the set of commands from a breakpoint.", nullptr) { AddSimpleArgumentList(eArgTypeBreakpointID); } ~CommandObjectBreakpointCommandDelete() override = default; Options *GetOptions() override { return &m_options; } class CommandOptions : public Options { public: CommandOptions() = default; ~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 'D': m_use_dummy = true; break; default: llvm_unreachable("Unimplemented option"); } return error; } void OptionParsingStarting(ExecutionContext *execution_context) override { m_use_dummy = false; } llvm::ArrayRef GetDefinitions() override { return llvm::ArrayRef(g_breakpoint_command_delete_options); } // Instance variables to hold the values for command options. bool m_use_dummy = false; }; protected: void DoExecute(Args &command, CommandReturnObject &result) override { Target &target = GetSelectedOrDummyTarget(m_options.m_use_dummy); const BreakpointList &breakpoints = target.GetBreakpointList(); size_t num_breakpoints = breakpoints.GetSize(); if (num_breakpoints == 0) { result.AppendError("No breakpoints exist to have commands deleted"); return; } if (command.empty()) { result.AppendError( "No breakpoint specified from which to delete the commands"); return; } BreakpointIDList valid_bp_ids; CommandObjectMultiwordBreakpoint::VerifyBreakpointOrLocationIDs( command, &target, result, &valid_bp_ids, BreakpointName::Permissions::PermissionKinds::listPerm); if (result.Succeeded()) { const size_t count = valid_bp_ids.GetSize(); for (size_t i = 0; i < count; ++i) { BreakpointID cur_bp_id = valid_bp_ids.GetBreakpointIDAtIndex(i); if (cur_bp_id.GetBreakpointID() != LLDB_INVALID_BREAK_ID) { Breakpoint *bp = target.GetBreakpointByID(cur_bp_id.GetBreakpointID()).get(); if (cur_bp_id.GetLocationID() != LLDB_INVALID_BREAK_ID) { BreakpointLocationSP bp_loc_sp( bp->FindLocationByID(cur_bp_id.GetLocationID())); if (bp_loc_sp) bp_loc_sp->ClearCallback(); else { result.AppendErrorWithFormat("Invalid breakpoint ID: %u.%u.\n", cur_bp_id.GetBreakpointID(), cur_bp_id.GetLocationID()); return; } } else { bp->ClearCallback(); } } } } } private: CommandOptions m_options; }; // CommandObjectBreakpointCommandList class CommandObjectBreakpointCommandList : public CommandObjectParsed { public: CommandObjectBreakpointCommandList(CommandInterpreter &interpreter) : CommandObjectParsed(interpreter, "list", "List the script or set of commands to be " "executed when the breakpoint is hit.", nullptr, eCommandRequiresTarget) { AddSimpleArgumentList(eArgTypeBreakpointID); } ~CommandObjectBreakpointCommandList() override = default; protected: void DoExecute(Args &command, CommandReturnObject &result) override { Target *target = &GetSelectedTarget(); const BreakpointList &breakpoints = target->GetBreakpointList(); size_t num_breakpoints = breakpoints.GetSize(); if (num_breakpoints == 0) { result.AppendError("No breakpoints exist for which to list commands"); return; } if (command.empty()) { result.AppendError( "No breakpoint specified for which to list the commands"); return; } BreakpointIDList valid_bp_ids; CommandObjectMultiwordBreakpoint::VerifyBreakpointOrLocationIDs( command, target, result, &valid_bp_ids, BreakpointName::Permissions::PermissionKinds::listPerm); if (result.Succeeded()) { const size_t count = valid_bp_ids.GetSize(); for (size_t i = 0; i < count; ++i) { BreakpointID cur_bp_id = valid_bp_ids.GetBreakpointIDAtIndex(i); if (cur_bp_id.GetBreakpointID() != LLDB_INVALID_BREAK_ID) { Breakpoint *bp = target->GetBreakpointByID(cur_bp_id.GetBreakpointID()).get(); if (bp) { BreakpointLocationSP bp_loc_sp; if (cur_bp_id.GetLocationID() != LLDB_INVALID_BREAK_ID) { bp_loc_sp = bp->FindLocationByID(cur_bp_id.GetLocationID()); if (!bp_loc_sp) { result.AppendErrorWithFormat("Invalid breakpoint ID: %u.%u.\n", cur_bp_id.GetBreakpointID(), cur_bp_id.GetLocationID()); return; } } StreamString id_str; BreakpointID::GetCanonicalReference(&id_str, cur_bp_id.GetBreakpointID(), cur_bp_id.GetLocationID()); const Baton *baton = nullptr; if (bp_loc_sp) baton = bp_loc_sp ->GetOptionsSpecifyingKind(BreakpointOptions::eCallback) .GetBaton(); else baton = bp->GetOptions().GetBaton(); if (baton) { result.GetOutputStream().Printf("Breakpoint %s:\n", id_str.GetData()); baton->GetDescription(result.GetOutputStream().AsRawOstream(), eDescriptionLevelFull, result.GetOutputStream().GetIndentLevel() + 2); } else { result.AppendMessageWithFormat( "Breakpoint %s does not have an associated command.\n", id_str.GetData()); } } result.SetStatus(eReturnStatusSuccessFinishResult); } else { result.AppendErrorWithFormat("Invalid breakpoint ID: %u.\n", cur_bp_id.GetBreakpointID()); } } } } }; // CommandObjectBreakpointCommand CommandObjectBreakpointCommand::CommandObjectBreakpointCommand( CommandInterpreter &interpreter) : CommandObjectMultiword( interpreter, "command", "Commands for adding, removing and listing " "LLDB commands executed when a breakpoint is " "hit.", "command [] ") { CommandObjectSP add_command_object( new CommandObjectBreakpointCommandAdd(interpreter)); CommandObjectSP delete_command_object( new CommandObjectBreakpointCommandDelete(interpreter)); CommandObjectSP list_command_object( new CommandObjectBreakpointCommandList(interpreter)); add_command_object->SetCommandName("breakpoint command add"); delete_command_object->SetCommandName("breakpoint command delete"); list_command_object->SetCommandName("breakpoint command list"); LoadSubCommand("add", add_command_object); LoadSubCommand("delete", delete_command_object); LoadSubCommand("list", list_command_object); } CommandObjectBreakpointCommand::~CommandObjectBreakpointCommand() = default;