LLDB mainline
CommandObjectWatchpointCommand.cpp
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1//===-- CommandObjectWatchpointCommand.cpp --------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include <vector>
10
15#include "lldb/Core/IOHandler.h"
21#include "lldb/Target/Target.h"
22
23using namespace lldb;
24using namespace lldb_private;
25
26#define LLDB_OPTIONS_watchpoint_command_add
27#include "CommandOptions.inc"
28
31public:
33 : CommandObjectParsed(interpreter, "add",
34 "Add a set of LLDB commands to a watchpoint, to be "
35 "executed whenever the watchpoint is hit. "
36 "The commands added to the watchpoint replace any "
37 "commands previously added to it.",
38 nullptr, eCommandRequiresTarget),
42 R"(
43General information about entering watchpoint commands
44------------------------------------------------------
45
46)"
47 "This command will prompt for commands to be executed when the specified \
48watchpoint is hit. Each command is typed on its own line following the '> ' \
49prompt until 'DONE' is entered."
50 R"(
51
52)"
53 "Syntactic errors may not be detected when initially entered, and many \
54malformed commands can silently fail when executed. If your watchpoint commands \
55do not appear to be executing, double-check the command syntax."
56 R"(
57
58)"
59 "Note: You may enter any debugger command exactly as you would at the debugger \
60prompt. There is no limit to the number of commands supplied, but do NOT enter \
61more than one command per line."
62 R"(
63
64Special information about PYTHON watchpoint commands
65----------------------------------------------------
66
67)"
68 "You may enter either one or more lines of Python, including function \
69definitions or calls to functions that will have been imported by the time \
70the code executes. Single line watchpoint commands will be interpreted 'as is' \
71when the watchpoint is hit. Multiple lines of Python will be wrapped in a \
72generated function, and a call to the function will be attached to the watchpoint."
73 R"(
74
75This auto-generated function is passed in three arguments:
76
77 frame: an lldb.SBFrame object for the frame which hit the watchpoint.
78
79 wp: the watchpoint that was hit.
80
81)"
82 "When specifying a python function with the --python-function option, you need \
83to supply the function name prepended by the module name:"
84 R"(
86 --python-function myutils.watchpoint_callback
88The function itself must have the following prototype:
90def watchpoint_callback(frame, wp):
91 # Your code goes here
92
93)"
94 "The arguments are the same as the arguments passed to generated functions as \
95described above. Note that the global variable 'lldb.frame' will NOT be updated when \
96this function is called, so be sure to use the 'frame' argument. The 'frame' argument \
97can get you to the thread via frame.GetThread(), the thread can get you to the \
98process via thread.GetProcess(), and the process can get you back to the target \
99via process.GetTarget()."
100 R"(
101
102)"
103 "Important Note: As Python code gets collected into functions, access to global \
104variables requires explicit scoping using the 'global' keyword. Be sure to use correct \
105Python syntax, including indentation, when entering Python watchpoint commands."
106 R"(
107
108Example Python one-line watchpoint command:
109
110(lldb) watchpoint command add -s python 1
111Enter your Python command(s). Type 'DONE' to end.
112> print "Hit this watchpoint!"
113> DONE
114
115As a convenience, this also works for a short Python one-liner:
116
117(lldb) watchpoint command add -s python 1 -o 'import time; print time.asctime()'
118(lldb) run
119Launching '.../a.out' (x86_64)
120(lldb) Fri Sep 10 12:17:45 2010
121Process 21778 Stopped
122* thread #1: tid = 0x2e03, 0x0000000100000de8 a.out`c + 7 at main.c:39, stop reason = watchpoint 1.1, queue = com.apple.main-thread
123 36
124 37 int c(int val)
125 38 {
126 39 -> return val + 3;
127 40 }
128 41
129 42 int main (int argc, char const *argv[])
130
131Example multiple line Python watchpoint command, using function definition:
132
133(lldb) watchpoint command add -s python 1
134Enter your Python command(s). Type 'DONE' to end.
135> def watchpoint_output (wp_no):
136> out_string = "Hit watchpoint number " + repr (wp_no)
137> print out_string
138> return True
139> watchpoint_output (1)
140> DONE
141
142Example multiple line Python watchpoint command, using 'loose' Python:
143
144(lldb) watchpoint command add -s p 1
145Enter your Python command(s). Type 'DONE' to end.
146> global wp_count
147> wp_count = wp_count + 1
148> print "Hit this watchpoint " + repr(wp_count) + " times!"
149> DONE
150
151)"
152 "In this case, since there is a reference to a global variable, \
153'wp_count', you will also need to make sure 'wp_count' exists and is \
154initialized:"
155 R"(
156
157(lldb) script
158>>> wp_count = 0
159>>> quit()
160
161)"
162 "Final Note: A warning that no watchpoint command was generated when there \
163are no syntax errors may indicate that a function was declared but never called.");
164
166 }
167
168 ~CommandObjectWatchpointCommandAdd() override = default;
169
170 Options *GetOptions() override { return &m_options; }
171
172 void IOHandlerActivated(IOHandler &io_handler, bool interactive) override {
173 StreamFileSP output_sp(io_handler.GetOutputStreamFileSP());
174 if (output_sp && interactive) {
175 output_sp->PutCString(
176 "Enter your debugger command(s). Type 'DONE' to end.\n");
177 output_sp->Flush();
178 }
179 }
180
181 void IOHandlerInputComplete(IOHandler &io_handler,
182 std::string &line) override {
183 io_handler.SetIsDone(true);
184
185 // The WatchpointOptions object is owned by the watchpoint or watchpoint
186 // location
187 WatchpointOptions *wp_options =
188 (WatchpointOptions *)io_handler.GetUserData();
189 if (wp_options) {
190 std::unique_ptr<WatchpointOptions::CommandData> data_up(
192 if (data_up) {
193 data_up->user_source.SplitIntoLines(line);
194 auto baton_sp = std::make_shared<WatchpointOptions::CommandBaton>(
195 std::move(data_up));
197 }
198 }
199 }
200
202 CommandReturnObject &result) {
204 "> ", // Prompt
205 *this, // IOHandlerDelegate
206 wp_options); // Baton for the "io_handler" that will be passed back into
207 // our IOHandlerDelegate functions
208 }
209
210 /// Set a one-liner as the callback for the watchpoint.
212 const char *oneliner) {
213 std::unique_ptr<WatchpointOptions::CommandData> data_up(
215
216 // It's necessary to set both user_source and script_source to the
217 // oneliner. The former is used to generate callback description (as in
218 // watchpoint command list) while the latter is used for Python to
219 // interpret during the actual callback.
220 data_up->user_source.AppendString(oneliner);
221 data_up->script_source.assign(oneliner);
222 data_up->stop_on_error = m_options.m_stop_on_error;
223
224 auto baton_sp =
225 std::make_shared<WatchpointOptions::CommandBaton>(std::move(data_up));
226 wp_options->SetCallback(WatchpointOptionsCallbackFunction, baton_sp);
227 }
228
229 static bool
232 lldb::user_id_t watch_id) {
233 bool ret_value = true;
234 if (baton == nullptr)
235 return true;
236
239 StringList &commands = data->user_source;
240
241 if (commands.GetSize() > 0) {
242 ExecutionContext exe_ctx(context->exe_ctx_ref);
243 Target *target = exe_ctx.GetTargetPtr();
244 if (target) {
245 Debugger &debugger = target->GetDebugger();
246 CommandReturnObject result(debugger.GetUseColor());
247
248 // Rig up the results secondary output stream to the debugger's, so the
249 // output will come out synchronously if the debugger is set up that
250 // way.
251 StreamSP output_stream(debugger.GetAsyncOutputStream());
252 StreamSP error_stream(debugger.GetAsyncErrorStream());
253 result.SetImmediateOutputStream(output_stream);
254 result.SetImmediateErrorStream(error_stream);
255
257 options.SetStopOnContinue(true);
258 options.SetStopOnError(data->stop_on_error);
259 options.SetEchoCommands(false);
260 options.SetPrintResults(true);
261 options.SetPrintErrors(true);
262 options.SetAddToHistory(false);
264 debugger.GetCommandInterpreter().HandleCommands(commands, exe_ctx,
265 options, result);
266 result.GetImmediateOutputStream()->Flush();
267 result.GetImmediateErrorStream()->Flush();
270 return ret_value;
271 }
272
273 class CommandOptions : public Options {
274 public:
275 CommandOptions() = default;
276
277 ~CommandOptions() override = default;
278
279 Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg,
280 ExecutionContext *execution_context) override {
282 const int short_option = m_getopt_table[option_idx].val;
283
284 switch (short_option) {
285 case 'o':
286 m_use_one_liner = true;
287 m_one_liner = std::string(option_arg);
288 break;
289
290 case 's':
292 option_arg, GetDefinitions()[option_idx].enum_values,
294
295 switch (m_script_language) {
299 break;
302 m_use_script_language = false;
303 break;
304 }
305 break;
306
307 case 'e': {
308 bool success = false;
310 OptionArgParser::ToBoolean(option_arg, false, &success);
311 if (!success)
312 error.SetErrorStringWithFormat(
313 "invalid value for stop-on-error: \"%s\"",
314 option_arg.str().c_str());
315 } break;
316
317 case 'F':
318 m_use_one_liner = false;
319 m_function_name.assign(std::string(option_arg));
320 break;
321
322 default:
323 llvm_unreachable("Unimplemented option");
324 }
325 return error;
326 }
327
328 void OptionParsingStarting(ExecutionContext *execution_context) override {
329 m_use_commands = true;
330 m_use_script_language = false;
332
333 m_use_one_liner = false;
334 m_stop_on_error = true;
335 m_one_liner.clear();
336 m_function_name.clear();
337 }
338
339 llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
340 return llvm::ArrayRef(g_watchpoint_command_add_options);
341 }
342
343 // Instance variables to hold the values for command options.
344
345 bool m_use_commands = false;
346 bool m_use_script_language = false;
348
349 // Instance variables to hold the values for one_liner options.
350 bool m_use_one_liner = false;
351 std::string m_one_liner;
353 std::string m_function_name;
354 };
355
356protected:
357 void DoExecute(Args &command, CommandReturnObject &result) override {
358 Target *target = &GetSelectedTarget();
359
360 const WatchpointList &watchpoints = target->GetWatchpointList();
361 size_t num_watchpoints = watchpoints.GetSize();
362
363 if (num_watchpoints == 0) {
364 result.AppendError("No watchpoints exist to have commands added");
365 return;
366 }
367
368 if (!m_options.m_function_name.empty()) {
372 }
373 }
374
375 std::vector<uint32_t> valid_wp_ids;
377 valid_wp_ids)) {
378 result.AppendError("Invalid watchpoints specification.");
379 return;
380 }
381
383 const size_t count = valid_wp_ids.size();
384 for (size_t i = 0; i < count; ++i) {
385 uint32_t cur_wp_id = valid_wp_ids.at(i);
386 if (cur_wp_id != LLDB_INVALID_WATCH_ID) {
387 Watchpoint *wp = target->GetWatchpointList().FindByID(cur_wp_id).get();
388 // Sanity check wp first.
389 if (wp == nullptr)
390 continue;
391
392 WatchpointOptions *wp_options = wp->GetOptions();
393 // Skip this watchpoint if wp_options is not good.
394 if (wp_options == nullptr)
395 continue;
396
397 // If we are using script language, get the script interpreter in order
398 // to set or collect command callback. Otherwise, call the methods
399 // associated with this object.
402 /*can_create=*/true, m_options.m_script_language);
403 // Special handling for one-liner specified inline.
405 script_interp->SetWatchpointCommandCallback(
406 wp_options, m_options.m_one_liner.c_str(),
407 /*is_callback=*/false);
408 }
409 // Special handling for using a Python function by name instead of
410 // extending the watchpoint callback data structures, we just
411 // automatize what the user would do manually: make their watchpoint
412 // command be a function call
413 else if (!m_options.m_function_name.empty()) {
414 std::string function_signature = m_options.m_function_name;
415 function_signature += "(frame, wp, internal_dict)";
416 script_interp->SetWatchpointCommandCallback(
417 wp_options, function_signature.c_str(), /*is_callback=*/true);
418 } else {
419 script_interp->CollectDataForWatchpointCommandCallback(wp_options,
420 result);
421 }
422 } else {
423 // Special handling for one-liner specified inline.
426 m_options.m_one_liner.c_str());
427 else
428 CollectDataForWatchpointCommandCallback(wp_options, result);
429 }
430 }
431 }
432 }
433
434private:
435 CommandOptions m_options;
436};
437
438// CommandObjectWatchpointCommandDelete
439
441public:
443 : CommandObjectParsed(interpreter, "delete",
444 "Delete the set of commands from a watchpoint.",
445 nullptr, eCommandRequiresTarget) {
447 }
448
450
451protected:
452 void DoExecute(Args &command, CommandReturnObject &result) override {
453 Target *target = &GetSelectedTarget();
454
455 const WatchpointList &watchpoints = target->GetWatchpointList();
456 size_t num_watchpoints = watchpoints.GetSize();
457
458 if (num_watchpoints == 0) {
459 result.AppendError("No watchpoints exist to have commands deleted");
460 return;
461 }
462
463 if (command.GetArgumentCount() == 0) {
464 result.AppendError(
465 "No watchpoint specified from which to delete the commands");
466 return;
467 }
468
469 std::vector<uint32_t> valid_wp_ids;
471 valid_wp_ids)) {
472 result.AppendError("Invalid watchpoints specification.");
473 return;
474 }
475
477 const size_t count = valid_wp_ids.size();
478 for (size_t i = 0; i < count; ++i) {
479 uint32_t cur_wp_id = valid_wp_ids.at(i);
480 if (cur_wp_id != LLDB_INVALID_WATCH_ID) {
481 Watchpoint *wp = target->GetWatchpointList().FindByID(cur_wp_id).get();
482 if (wp)
483 wp->ClearCallback();
484 } else {
485 result.AppendErrorWithFormat("Invalid watchpoint ID: %u.\n", cur_wp_id);
486 return;
487 }
488 }
489 }
490};
491
492// CommandObjectWatchpointCommandList
493
495public:
497 : CommandObjectParsed(interpreter, "list",
498 "List the script or set of commands to be executed "
499 "when the watchpoint is hit.",
500 nullptr, eCommandRequiresTarget) {
502 }
503
505
506protected:
507 void DoExecute(Args &command, CommandReturnObject &result) override {
508 Target *target = &GetSelectedTarget();
509
510 const WatchpointList &watchpoints = target->GetWatchpointList();
511 size_t num_watchpoints = watchpoints.GetSize();
512
513 if (num_watchpoints == 0) {
514 result.AppendError("No watchpoints exist for which to list commands");
515 return;
516 }
517
518 if (command.GetArgumentCount() == 0) {
519 result.AppendError(
520 "No watchpoint specified for which to list the commands");
521 return;
522 }
523
524 std::vector<uint32_t> valid_wp_ids;
526 valid_wp_ids)) {
527 result.AppendError("Invalid watchpoints specification.");
528 return;
529 }
530
532 const size_t count = valid_wp_ids.size();
533 for (size_t i = 0; i < count; ++i) {
534 uint32_t cur_wp_id = valid_wp_ids.at(i);
535 if (cur_wp_id != LLDB_INVALID_WATCH_ID) {
536 Watchpoint *wp = target->GetWatchpointList().FindByID(cur_wp_id).get();
537
538 if (wp) {
539 const WatchpointOptions *wp_options = wp->GetOptions();
540 if (wp_options) {
541 // Get the callback baton associated with the current watchpoint.
542 const Baton *baton = wp_options->GetBaton();
543 if (baton) {
544 result.GetOutputStream().Printf("Watchpoint %u:\n", cur_wp_id);
548 2);
549 } else {
551 "Watchpoint %u does not have an associated command.\n",
552 cur_wp_id);
553 }
554 }
556 } else {
557 result.AppendErrorWithFormat("Invalid watchpoint ID: %u.\n",
558 cur_wp_id);
559 }
560 }
561 }
562 }
563};
564
565// CommandObjectWatchpointCommand
566
568 CommandInterpreter &interpreter)
570 interpreter, "command",
571 "Commands for adding, removing and examining LLDB commands "
572 "executed when the watchpoint is hit (watchpoint 'commands').",
573 "command <sub-command> [<sub-command-options>] <watchpoint-id>") {
574 CommandObjectSP add_command_object(
575 new CommandObjectWatchpointCommandAdd(interpreter));
576 CommandObjectSP delete_command_object(
577 new CommandObjectWatchpointCommandDelete(interpreter));
578 CommandObjectSP list_command_object(
579 new CommandObjectWatchpointCommandList(interpreter));
580
581 add_command_object->SetCommandName("watchpoint command add");
582 delete_command_object->SetCommandName("watchpoint command delete");
583 list_command_object->SetCommandName("watchpoint command list");
584
585 LoadSubCommand("add", add_command_object);
586 LoadSubCommand("delete", delete_command_object);
587 LoadSubCommand("list", list_command_object);
588}
589
static llvm::raw_ostream & error(Stream &strm)
void OptionParsingStarting(ExecutionContext *execution_context) override
llvm::ArrayRef< OptionDefinition > GetDefinitions() override
Status SetOptionValue(uint32_t option_idx, llvm::StringRef option_arg, ExecutionContext *execution_context) override
Set the value of an option.
void SetWatchpointCommandCallback(WatchpointOptions *wp_options, const char *oneliner)
Set a one-liner as the callback for the watchpoint.
CommandObjectWatchpointCommandAdd(CommandInterpreter &interpreter)
static bool WatchpointOptionsCallbackFunction(void *baton, StoppointCallbackContext *context, lldb::user_id_t watch_id)
~CommandObjectWatchpointCommandAdd() override=default
void IOHandlerActivated(IOHandler &io_handler, bool interactive) override
void DoExecute(Args &command, CommandReturnObject &result) override
void IOHandlerInputComplete(IOHandler &io_handler, std::string &line) override
Called when a line or lines have been retrieved.
void CollectDataForWatchpointCommandCallback(WatchpointOptions *wp_options, CommandReturnObject &result)
CommandObjectWatchpointCommandDelete(CommandInterpreter &interpreter)
~CommandObjectWatchpointCommandDelete() override=default
void DoExecute(Args &command, CommandReturnObject &result) override
CommandObjectWatchpointCommandList(CommandInterpreter &interpreter)
~CommandObjectWatchpointCommandList() override=default
void DoExecute(Args &command, CommandReturnObject &result) override
A command line argument class.
Definition: Args.h:33
size_t GetArgumentCount() const
Gets the number of arguments left in this command object.
Definition: Args.h:116
A class designed to wrap callback batons so they can cleanup any acquired resources.
Definition: Baton.h:35
virtual void GetDescription(llvm::raw_ostream &s, lldb::DescriptionLevel level, unsigned indentation) const =0
void SetStopOnContinue(bool stop_on_continue)
void GetLLDBCommandsFromIOHandler(const char *prompt, IOHandlerDelegate &delegate, void *baton=nullptr)
void HandleCommands(const StringList &commands, const ExecutionContext &context, const CommandInterpreterRunOptions &options, CommandReturnObject &result)
Execute a list of commands in sequence.
static bool VerifyWatchpointIDs(Target *target, Args &args, std::vector< uint32_t > &wp_ids)
bool LoadSubCommand(llvm::StringRef cmd_name, const lldb::CommandObjectSP &command_obj) override
virtual void SetHelpLong(llvm::StringRef str)
void AddSimpleArgumentList(lldb::CommandArgumentType arg_type, ArgumentRepetitionType repetition_type=eArgRepeatPlain)
CommandInterpreter & m_interpreter
void void AppendError(llvm::StringRef in_string)
void SetStatus(lldb::ReturnStatus status)
void AppendErrorWithFormat(const char *format,...) __attribute__((format(printf
void AppendMessageWithFormat(const char *format,...) __attribute__((format(printf
A class to manage flag bits.
Definition: Debugger.h:80
lldb::StreamSP GetAsyncOutputStream()
Definition: Debugger.cpp:1289
CommandInterpreter & GetCommandInterpreter()
Definition: Debugger.h:168
bool GetUseColor() const
Definition: Debugger.cpp:403
lldb::StreamSP GetAsyncErrorStream()
Definition: Debugger.cpp:1293
lldb::ScriptLanguage GetScriptLanguage() const
Definition: Debugger.cpp:345
ScriptInterpreter * GetScriptInterpreter(bool can_create=true, std::optional< lldb::ScriptLanguage > language={})
Definition: Debugger.cpp:1684
"lldb/Target/ExecutionContext.h" A class that contains an execution context.
A delegate class for use with IOHandler subclasses.
Definition: IOHandler.h:190
lldb::StreamFileSP GetOutputStreamFileSP()
Definition: IOHandler.cpp:105
void SetIsDone(bool b)
Definition: IOHandler.h:86
A command line option parsing protocol class.
Definition: Options.h:58
std::vector< Option > m_getopt_table
Definition: Options.h:198
virtual void SetWatchpointCommandCallback(WatchpointOptions *wp_options, const char *user_input, bool is_callback)
Set a one-liner as the callback for the watchpoint.
virtual void CollectDataForWatchpointCommandCallback(WatchpointOptions *wp_options, CommandReturnObject &result)
An error handling class.
Definition: Status.h:44
General Outline: When we hit a breakpoint we need to package up whatever information is needed to eva...
llvm::raw_ostream & AsRawOstream()
Returns a raw_ostream that forwards the data to this Stream object.
Definition: Stream.h:401
size_t Printf(const char *format,...) __attribute__((format(printf
Output printf formatted output to the stream.
Definition: Stream.cpp:134
unsigned GetIndentLevel() const
Get the current indentation level.
Definition: Stream.cpp:187
size_t GetSize() const
Definition: StringList.cpp:74
Debugger & GetDebugger()
Definition: Target.h:1064
WatchpointList & GetWatchpointList()
Definition: Target.h:774
This class is used by Watchpoint to manage a list of watchpoints,.
lldb::WatchpointSP FindByID(lldb::watch_id_t watchID) const
Returns a shared pointer to the watchpoint with id watchID, const version.
size_t GetSize() const
Returns the number of elements in this watchpoint list.
"lldb/Breakpoint/WatchpointOptions.h" Class that manages the options on a watchpoint.
void SetCallback(WatchpointHitCallback callback, const lldb::BatonSP &baton_sp, bool synchronous=false)
Adds a callback to the watchpoint option set.
Baton * GetBaton()
Fetch the baton from the callback.
WatchpointOptions * GetOptions()
Returns the WatchpointOptions structure set for this watchpoint.
Definition: Watchpoint.h:138
#define LLDB_INVALID_WATCH_ID
Definition: lldb-defines.h:43
A class that represents a running process on the host machine.
Definition: SBAttachInfo.h:14
Definition: SBAddress.h:15
ScriptLanguage
Script interpreter types.
@ eScriptLanguageUnknown
@ eScriptLanguageLua
@ eScriptLanguageNone
@ eScriptLanguagePython
@ eDescriptionLevelFull
std::shared_ptr< lldb_private::CommandObject > CommandObjectSP
Definition: lldb-forward.h:325
std::shared_ptr< lldb_private::Stream > StreamSP
Definition: lldb-forward.h:420
@ eReturnStatusSuccessFinishResult
@ eReturnStatusSuccessFinishNoResult
@ eArgTypeWatchpointID
std::shared_ptr< lldb_private::StreamFile > StreamFileSP
Definition: lldb-forward.h:421
uint64_t user_id_t
Definition: lldb-types.h:82
static int64_t ToOptionEnum(llvm::StringRef s, const OptionEnumValues &enum_values, int32_t fail_value, Status &error)
static bool ToBoolean(llvm::StringRef s, bool fail_value, bool *success_ptr)