llvm-capstone/lldb/source/Commands/CommandObjectWatchpoint.cpp
Jason Molenda c73a3f16f8 [lldb] [mostly NFC] Large WP foundation: WatchpointResources (#68845)
This patch is rearranging code a bit to add WatchpointResources to
Process. A WatchpointResource is meant to represent a hardware
watchpoint register in the inferior process. It has an address, a size,
a type, and a list of Watchpoints that are using this
WatchpointResource.

This current patch doesn't add any of the features of
WatchpointResources that make them interesting -- a user asking to watch
a 24 byte object could watch this with three 8 byte WatchpointResources.
Or a Watchpoint on 1 byte at 0x1002 and a second watchpoint on 1 byte at
0x1003, these must both be served by a single WatchpointResource on that
doubleword at 0x1000 on a 64-bit target, if two hardware watchpoint
registers were used to track these separately, one of them may not be
hit. Or if you have one Watchpoint on a variable with a condition set,
and another Watchpoint on that same variable with a command defined or
different condition, or ignorecount, both of those Watchpoints need to
evaluate their criteria/commands when their WatchpointResource has been
hit.

There's a bit of code movement to rearrange things in the direction I'll
need for implementing this feature, so I want to start with reviewing &
landing this mostly NFC patch and we can focus on the algorithmic
choices about how WatchpointResources are shared and handled as they're
triggeed, separately.

This patch also stops printing "Watchpoint <n> hit: old value: <x>, new
vlaue: <y>" for Read watchpoints. I could make an argument for print
"Watchpoint <n> hit: current value <x>" but the current output doesn't
make any sense, and the user can print the value if they are
particularly interested. Read watchpoints are used primarily to
understand what code is reading a variable.

This patch adds more fallbacks for how to print the objects being
watched if we have types, instead of assuming they are all integral
values, so a struct will print its elements. As large watchpoints are
added, we'll be doing a lot more of those.

To track the WatchpointSP in the WatchpointResources, I changed the
internal API which took a WatchpointSP and devolved it to a Watchpoint*,
which meant touching several different Process files. I removed the
watchpoint code in ProcessKDP which only reported that watchpoints
aren't supported, the base class does that already.

I haven't yet changed how we receive a watchpoint to identify the
WatchpointResource responsible for the trigger, and identify all
Watchpoints that are using this Resource to evaluate their conditions
etc. This is the same work that a BreakpointSite needs to do when it has
been tiggered, where multiple Breakpoints may be at the same address.

There is not yet any printing of the Resources that a Watchpoint is
implemented in terms of ("watchpoint list", or
SBWatchpoint::GetDescription).

"watchpoint set var" and "watchpoint set expression" take a size
argument which was previously 1, 2, 4, or 8 (an enum). I've changed this
to an unsigned int. Most hardware implementations can only watch 1, 2,
4, 8 byte ranges, but with Resources we'll allow a user to ask for
different sized watchpoints and set them in hardware-expressble terms
soon.

I've annotated areas where I know there is work still needed with
LWP_TODO that I'll be working on once this is landed.

I've tested this on aarch64 macOS, aarch64 Linux, and Intel macOS.

https://discourse.llvm.org/t/rfc-large-watchpoint-support-in-lldb/72116
(cherry picked from commit fc6b72523f3d73b921690a713e97a433c96066c6)
2023-11-30 14:59:10 -08:00

1235 lines
42 KiB
C++

//===-- CommandObjectWatchpoint.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 "CommandObjectWatchpoint.h"
#include "CommandObjectWatchpointCommand.h"
#include <memory>
#include <vector>
#include "llvm/ADT/StringRef.h"
#include "lldb/Breakpoint/Watchpoint.h"
#include "lldb/Breakpoint/WatchpointList.h"
#include "lldb/Core/ValueObject.h"
#include "lldb/Host/OptionParser.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/CommandOptionArgumentTable.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Symbol/Function.h"
#include "lldb/Symbol/Variable.h"
#include "lldb/Symbol/VariableList.h"
#include "lldb/Target/StackFrame.h"
#include "lldb/Target/Target.h"
#include "lldb/Utility/StreamString.h"
using namespace lldb;
using namespace lldb_private;
static void AddWatchpointDescription(Stream &s, Watchpoint &wp,
lldb::DescriptionLevel level) {
s.IndentMore();
wp.GetDescription(&s, level);
s.IndentLess();
s.EOL();
}
static bool CheckTargetForWatchpointOperations(Target *target,
CommandReturnObject &result) {
bool process_is_valid =
target->GetProcessSP() && target->GetProcessSP()->IsAlive();
if (!process_is_valid) {
result.AppendError("There's no process or it is not alive.");
return false;
}
// Target passes our checks, return true.
return true;
}
// Equivalent class: {"-", "to", "To", "TO"} of range specifier array.
static const char *RSA[4] = {"-", "to", "To", "TO"};
// Return the index to RSA if found; otherwise -1 is returned.
static int32_t WithRSAIndex(llvm::StringRef Arg) {
uint32_t i;
for (i = 0; i < 4; ++i)
if (Arg.contains(RSA[i]))
return i;
return -1;
}
// Return true if wp_ids is successfully populated with the watch ids. False
// otherwise.
bool CommandObjectMultiwordWatchpoint::VerifyWatchpointIDs(
Target *target, Args &args, std::vector<uint32_t> &wp_ids) {
// Pre-condition: args.GetArgumentCount() > 0.
if (args.GetArgumentCount() == 0) {
if (target == nullptr)
return false;
WatchpointSP watch_sp = target->GetLastCreatedWatchpoint();
if (watch_sp) {
wp_ids.push_back(watch_sp->GetID());
return true;
} else
return false;
}
llvm::StringRef Minus("-");
std::vector<llvm::StringRef> StrRefArgs;
llvm::StringRef first;
llvm::StringRef second;
size_t i;
int32_t idx;
// Go through the arguments and make a canonical form of arg list containing
// only numbers with possible "-" in between.
for (auto &entry : args.entries()) {
if ((idx = WithRSAIndex(entry.ref())) == -1) {
StrRefArgs.push_back(entry.ref());
continue;
}
// The Arg contains the range specifier, split it, then.
std::tie(first, second) = entry.ref().split(RSA[idx]);
if (!first.empty())
StrRefArgs.push_back(first);
StrRefArgs.push_back(Minus);
if (!second.empty())
StrRefArgs.push_back(second);
}
// Now process the canonical list and fill in the vector of uint32_t's. If
// there is any error, return false and the client should ignore wp_ids.
uint32_t beg, end, id;
size_t size = StrRefArgs.size();
bool in_range = false;
for (i = 0; i < size; ++i) {
llvm::StringRef Arg = StrRefArgs[i];
if (in_range) {
// Look for the 'end' of the range. Note StringRef::getAsInteger()
// returns true to signify error while parsing.
if (Arg.getAsInteger(0, end))
return false;
// Found a range! Now append the elements.
for (id = beg; id <= end; ++id)
wp_ids.push_back(id);
in_range = false;
continue;
}
if (i < (size - 1) && StrRefArgs[i + 1] == Minus) {
if (Arg.getAsInteger(0, beg))
return false;
// Turn on the in_range flag, we are looking for end of range next.
++i;
in_range = true;
continue;
}
// Otherwise, we have a simple ID. Just append it.
if (Arg.getAsInteger(0, beg))
return false;
wp_ids.push_back(beg);
}
// It is an error if after the loop, we're still in_range.
return !in_range;
}
// CommandObjectWatchpointList
// CommandObjectWatchpointList::Options
#pragma mark List::CommandOptions
#define LLDB_OPTIONS_watchpoint_list
#include "CommandOptions.inc"
#pragma mark List
class CommandObjectWatchpointList : public CommandObjectParsed {
public:
CommandObjectWatchpointList(CommandInterpreter &interpreter)
: CommandObjectParsed(
interpreter, "watchpoint list",
"List all watchpoints at configurable levels of detail.", nullptr,
eCommandRequiresTarget) {
CommandArgumentEntry arg;
CommandObject::AddIDsArgumentData(arg, eArgTypeWatchpointID,
eArgTypeWatchpointIDRange);
// Add the entry for the first argument for this command to the object's
// arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectWatchpointList() 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 'b':
m_level = lldb::eDescriptionLevelBrief;
break;
case 'f':
m_level = lldb::eDescriptionLevelFull;
break;
case 'v':
m_level = lldb::eDescriptionLevelVerbose;
break;
default:
llvm_unreachable("Unimplemented option");
}
return error;
}
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_level = lldb::eDescriptionLevelFull;
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::ArrayRef(g_watchpoint_list_options);
}
// Instance variables to hold the values for command options.
lldb::DescriptionLevel m_level = lldb::eDescriptionLevelBrief;
};
protected:
void DoExecute(Args &command, CommandReturnObject &result) override {
Target *target = &GetSelectedTarget();
if (target->GetProcessSP() && target->GetProcessSP()->IsAlive()) {
std::optional<uint32_t> num_supported_hardware_watchpoints =
target->GetProcessSP()->GetWatchpointSlotCount();
if (num_supported_hardware_watchpoints)
result.AppendMessageWithFormat(
"Number of supported hardware watchpoints: %u\n",
*num_supported_hardware_watchpoints);
}
const WatchpointList &watchpoints = target->GetWatchpointList();
std::unique_lock<std::recursive_mutex> lock;
target->GetWatchpointList().GetListMutex(lock);
size_t num_watchpoints = watchpoints.GetSize();
if (num_watchpoints == 0) {
result.AppendMessage("No watchpoints currently set.");
result.SetStatus(eReturnStatusSuccessFinishNoResult);
return;
}
Stream &output_stream = result.GetOutputStream();
if (command.GetArgumentCount() == 0) {
// No watchpoint selected; show info about all currently set watchpoints.
result.AppendMessage("Current watchpoints:");
for (size_t i = 0; i < num_watchpoints; ++i) {
WatchpointSP watch_sp = watchpoints.GetByIndex(i);
AddWatchpointDescription(output_stream, *watch_sp, m_options.m_level);
}
result.SetStatus(eReturnStatusSuccessFinishNoResult);
} else {
// Particular watchpoints selected; enable them.
std::vector<uint32_t> wp_ids;
if (!CommandObjectMultiwordWatchpoint::VerifyWatchpointIDs(
target, command, wp_ids)) {
result.AppendError("Invalid watchpoints specification.");
return;
}
const size_t size = wp_ids.size();
for (size_t i = 0; i < size; ++i) {
WatchpointSP watch_sp = watchpoints.FindByID(wp_ids[i]);
if (watch_sp)
AddWatchpointDescription(output_stream, *watch_sp, m_options.m_level);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
}
}
}
private:
CommandOptions m_options;
};
// CommandObjectWatchpointEnable
#pragma mark Enable
class CommandObjectWatchpointEnable : public CommandObjectParsed {
public:
CommandObjectWatchpointEnable(CommandInterpreter &interpreter)
: CommandObjectParsed(interpreter, "enable",
"Enable the specified disabled watchpoint(s). If "
"no watchpoints are specified, enable all of them.",
nullptr, eCommandRequiresTarget) {
CommandArgumentEntry arg;
CommandObject::AddIDsArgumentData(arg, eArgTypeWatchpointID,
eArgTypeWatchpointIDRange);
// Add the entry for the first argument for this command to the object's
// arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectWatchpointEnable() override = default;
void
HandleArgumentCompletion(CompletionRequest &request,
OptionElementVector &opt_element_vector) override {
lldb_private::CommandCompletions::InvokeCommonCompletionCallbacks(
GetCommandInterpreter(), lldb::eWatchpointIDCompletion, request,
nullptr);
}
protected:
void DoExecute(Args &command, CommandReturnObject &result) override {
Target *target = &GetSelectedTarget();
if (!CheckTargetForWatchpointOperations(target, result))
return;
std::unique_lock<std::recursive_mutex> lock;
target->GetWatchpointList().GetListMutex(lock);
const WatchpointList &watchpoints = target->GetWatchpointList();
size_t num_watchpoints = watchpoints.GetSize();
if (num_watchpoints == 0) {
result.AppendError("No watchpoints exist to be enabled.");
return;
}
if (command.GetArgumentCount() == 0) {
// No watchpoint selected; enable all currently set watchpoints.
target->EnableAllWatchpoints();
result.AppendMessageWithFormat("All watchpoints enabled. (%" PRIu64
" watchpoints)\n",
(uint64_t)num_watchpoints);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
} else {
// Particular watchpoints selected; enable them.
std::vector<uint32_t> wp_ids;
if (!CommandObjectMultiwordWatchpoint::VerifyWatchpointIDs(
target, command, wp_ids)) {
result.AppendError("Invalid watchpoints specification.");
return;
}
int count = 0;
const size_t size = wp_ids.size();
for (size_t i = 0; i < size; ++i)
if (target->EnableWatchpointByID(wp_ids[i]))
++count;
result.AppendMessageWithFormat("%d watchpoints enabled.\n", count);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
}
}
};
// CommandObjectWatchpointDisable
#pragma mark Disable
class CommandObjectWatchpointDisable : public CommandObjectParsed {
public:
CommandObjectWatchpointDisable(CommandInterpreter &interpreter)
: CommandObjectParsed(interpreter, "watchpoint disable",
"Disable the specified watchpoint(s) without "
"removing it/them. If no watchpoints are "
"specified, disable them all.",
nullptr, eCommandRequiresTarget) {
CommandArgumentEntry arg;
CommandObject::AddIDsArgumentData(arg, eArgTypeWatchpointID,
eArgTypeWatchpointIDRange);
// Add the entry for the first argument for this command to the object's
// arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectWatchpointDisable() override = default;
void
HandleArgumentCompletion(CompletionRequest &request,
OptionElementVector &opt_element_vector) override {
lldb_private::CommandCompletions::InvokeCommonCompletionCallbacks(
GetCommandInterpreter(), lldb::eWatchpointIDCompletion, request,
nullptr);
}
protected:
void DoExecute(Args &command, CommandReturnObject &result) override {
Target *target = &GetSelectedTarget();
if (!CheckTargetForWatchpointOperations(target, result))
return;
std::unique_lock<std::recursive_mutex> lock;
target->GetWatchpointList().GetListMutex(lock);
const WatchpointList &watchpoints = target->GetWatchpointList();
size_t num_watchpoints = watchpoints.GetSize();
if (num_watchpoints == 0) {
result.AppendError("No watchpoints exist to be disabled.");
return;
}
if (command.GetArgumentCount() == 0) {
// No watchpoint selected; disable all currently set watchpoints.
if (target->DisableAllWatchpoints()) {
result.AppendMessageWithFormat("All watchpoints disabled. (%" PRIu64
" watchpoints)\n",
(uint64_t)num_watchpoints);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
} else {
result.AppendError("Disable all watchpoints failed\n");
}
} else {
// Particular watchpoints selected; disable them.
std::vector<uint32_t> wp_ids;
if (!CommandObjectMultiwordWatchpoint::VerifyWatchpointIDs(
target, command, wp_ids)) {
result.AppendError("Invalid watchpoints specification.");
return;
}
int count = 0;
const size_t size = wp_ids.size();
for (size_t i = 0; i < size; ++i)
if (target->DisableWatchpointByID(wp_ids[i]))
++count;
result.AppendMessageWithFormat("%d watchpoints disabled.\n", count);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
}
}
};
// CommandObjectWatchpointDelete
#define LLDB_OPTIONS_watchpoint_delete
#include "CommandOptions.inc"
// CommandObjectWatchpointDelete
#pragma mark Delete
class CommandObjectWatchpointDelete : public CommandObjectParsed {
public:
CommandObjectWatchpointDelete(CommandInterpreter &interpreter)
: CommandObjectParsed(interpreter, "watchpoint delete",
"Delete the specified watchpoint(s). If no "
"watchpoints are specified, delete them all.",
nullptr, eCommandRequiresTarget) {
CommandArgumentEntry arg;
CommandObject::AddIDsArgumentData(arg, eArgTypeWatchpointID,
eArgTypeWatchpointIDRange);
// Add the entry for the first argument for this command to the object's
// arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectWatchpointDelete() override = default;
void
HandleArgumentCompletion(CompletionRequest &request,
OptionElementVector &opt_element_vector) override {
lldb_private::CommandCompletions::InvokeCommonCompletionCallbacks(
GetCommandInterpreter(), lldb::eWatchpointIDCompletion, request,
nullptr);
}
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 {
const int short_option = m_getopt_table[option_idx].val;
switch (short_option) {
case 'f':
m_force = true;
break;
default:
llvm_unreachable("Unimplemented option");
}
return {};
}
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_force = false;
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::ArrayRef(g_watchpoint_delete_options);
}
// Instance variables to hold the values for command options.
bool m_force = false;
};
protected:
void DoExecute(Args &command, CommandReturnObject &result) override {
Target *target = &GetSelectedTarget();
if (!CheckTargetForWatchpointOperations(target, result))
return;
std::unique_lock<std::recursive_mutex> lock;
target->GetWatchpointList().GetListMutex(lock);
const WatchpointList &watchpoints = target->GetWatchpointList();
size_t num_watchpoints = watchpoints.GetSize();
if (num_watchpoints == 0) {
result.AppendError("No watchpoints exist to be deleted.");
return;
}
if (command.empty()) {
if (!m_options.m_force &&
!m_interpreter.Confirm(
"About to delete all watchpoints, do you want to do that?",
true)) {
result.AppendMessage("Operation cancelled...");
} else {
target->RemoveAllWatchpoints();
result.AppendMessageWithFormat("All watchpoints removed. (%" PRIu64
" watchpoints)\n",
(uint64_t)num_watchpoints);
}
result.SetStatus(eReturnStatusSuccessFinishNoResult);
return;
}
// Particular watchpoints selected; delete them.
std::vector<uint32_t> wp_ids;
if (!CommandObjectMultiwordWatchpoint::VerifyWatchpointIDs(target, command,
wp_ids)) {
result.AppendError("Invalid watchpoints specification.");
return;
}
int count = 0;
const size_t size = wp_ids.size();
for (size_t i = 0; i < size; ++i)
if (target->RemoveWatchpointByID(wp_ids[i]))
++count;
result.AppendMessageWithFormat("%d watchpoints deleted.\n", count);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
}
private:
CommandOptions m_options;
};
// CommandObjectWatchpointIgnore
#pragma mark Ignore::CommandOptions
#define LLDB_OPTIONS_watchpoint_ignore
#include "CommandOptions.inc"
class CommandObjectWatchpointIgnore : public CommandObjectParsed {
public:
CommandObjectWatchpointIgnore(CommandInterpreter &interpreter)
: CommandObjectParsed(interpreter, "watchpoint ignore",
"Set ignore count on the specified watchpoint(s). "
"If no watchpoints are specified, set them all.",
nullptr, eCommandRequiresTarget) {
CommandArgumentEntry arg;
CommandObject::AddIDsArgumentData(arg, eArgTypeWatchpointID,
eArgTypeWatchpointIDRange);
// Add the entry for the first argument for this command to the object's
// arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectWatchpointIgnore() override = default;
void
HandleArgumentCompletion(CompletionRequest &request,
OptionElementVector &opt_element_vector) override {
lldb_private::CommandCompletions::InvokeCommonCompletionCallbacks(
GetCommandInterpreter(), lldb::eWatchpointIDCompletion, request,
nullptr);
}
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 'i':
if (option_arg.getAsInteger(0, m_ignore_count))
error.SetErrorStringWithFormat("invalid ignore count '%s'",
option_arg.str().c_str());
break;
default:
llvm_unreachable("Unimplemented option");
}
return error;
}
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_ignore_count = 0;
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::ArrayRef(g_watchpoint_ignore_options);
}
// Instance variables to hold the values for command options.
uint32_t m_ignore_count = 0;
};
protected:
void DoExecute(Args &command, CommandReturnObject &result) override {
Target *target = &GetSelectedTarget();
if (!CheckTargetForWatchpointOperations(target, result))
return;
std::unique_lock<std::recursive_mutex> lock;
target->GetWatchpointList().GetListMutex(lock);
const WatchpointList &watchpoints = target->GetWatchpointList();
size_t num_watchpoints = watchpoints.GetSize();
if (num_watchpoints == 0) {
result.AppendError("No watchpoints exist to be ignored.");
return;
}
if (command.GetArgumentCount() == 0) {
target->IgnoreAllWatchpoints(m_options.m_ignore_count);
result.AppendMessageWithFormat("All watchpoints ignored. (%" PRIu64
" watchpoints)\n",
(uint64_t)num_watchpoints);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
} else {
// Particular watchpoints selected; ignore them.
std::vector<uint32_t> wp_ids;
if (!CommandObjectMultiwordWatchpoint::VerifyWatchpointIDs(
target, command, wp_ids)) {
result.AppendError("Invalid watchpoints specification.");
return;
}
int count = 0;
const size_t size = wp_ids.size();
for (size_t i = 0; i < size; ++i)
if (target->IgnoreWatchpointByID(wp_ids[i], m_options.m_ignore_count))
++count;
result.AppendMessageWithFormat("%d watchpoints ignored.\n", count);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
}
}
private:
CommandOptions m_options;
};
// CommandObjectWatchpointModify
#pragma mark Modify::CommandOptions
#define LLDB_OPTIONS_watchpoint_modify
#include "CommandOptions.inc"
#pragma mark Modify
class CommandObjectWatchpointModify : public CommandObjectParsed {
public:
CommandObjectWatchpointModify(CommandInterpreter &interpreter)
: CommandObjectParsed(
interpreter, "watchpoint modify",
"Modify the options on a watchpoint or set of watchpoints in the "
"executable. "
"If no watchpoint is specified, act on the last created "
"watchpoint. "
"Passing an empty argument clears the modification.",
nullptr, eCommandRequiresTarget) {
CommandArgumentEntry arg;
CommandObject::AddIDsArgumentData(arg, eArgTypeWatchpointID,
eArgTypeWatchpointIDRange);
// Add the entry for the first argument for this command to the object's
// arguments vector.
m_arguments.push_back(arg);
}
~CommandObjectWatchpointModify() override = default;
void
HandleArgumentCompletion(CompletionRequest &request,
OptionElementVector &opt_element_vector) override {
lldb_private::CommandCompletions::InvokeCommonCompletionCallbacks(
GetCommandInterpreter(), lldb::eWatchpointIDCompletion, request,
nullptr);
}
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 'c':
m_condition = std::string(option_arg);
m_condition_passed = true;
break;
default:
llvm_unreachable("Unimplemented option");
}
return error;
}
void OptionParsingStarting(ExecutionContext *execution_context) override {
m_condition.clear();
m_condition_passed = false;
}
llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
return llvm::ArrayRef(g_watchpoint_modify_options);
}
// Instance variables to hold the values for command options.
std::string m_condition;
bool m_condition_passed = false;
};
protected:
void DoExecute(Args &command, CommandReturnObject &result) override {
Target *target = &GetSelectedTarget();
if (!CheckTargetForWatchpointOperations(target, result))
return;
std::unique_lock<std::recursive_mutex> lock;
target->GetWatchpointList().GetListMutex(lock);
const WatchpointList &watchpoints = target->GetWatchpointList();
size_t num_watchpoints = watchpoints.GetSize();
if (num_watchpoints == 0) {
result.AppendError("No watchpoints exist to be modified.");
return;
}
if (command.GetArgumentCount() == 0) {
WatchpointSP watch_sp = target->GetLastCreatedWatchpoint();
watch_sp->SetCondition(m_options.m_condition.c_str());
result.SetStatus(eReturnStatusSuccessFinishNoResult);
} else {
// Particular watchpoints selected; set condition on them.
std::vector<uint32_t> wp_ids;
if (!CommandObjectMultiwordWatchpoint::VerifyWatchpointIDs(
target, command, wp_ids)) {
result.AppendError("Invalid watchpoints specification.");
return;
}
int count = 0;
const size_t size = wp_ids.size();
for (size_t i = 0; i < size; ++i) {
WatchpointSP watch_sp = watchpoints.FindByID(wp_ids[i]);
if (watch_sp) {
watch_sp->SetCondition(m_options.m_condition.c_str());
++count;
}
}
result.AppendMessageWithFormat("%d watchpoints modified.\n", count);
result.SetStatus(eReturnStatusSuccessFinishNoResult);
}
}
private:
CommandOptions m_options;
};
// CommandObjectWatchpointSetVariable
#pragma mark SetVariable
class CommandObjectWatchpointSetVariable : public CommandObjectParsed {
public:
CommandObjectWatchpointSetVariable(CommandInterpreter &interpreter)
: CommandObjectParsed(
interpreter, "watchpoint set variable",
"Set a watchpoint on a variable. "
"Use the '-w' option to specify the type of watchpoint and "
"the '-s' option to specify the byte size to watch for. "
"If no '-w' option is specified, it defaults to modify. "
"If no '-s' option is specified, it defaults to the variable's "
"byte size. "
"Note that there are limited hardware resources for watchpoints. "
"If watchpoint setting fails, consider disable/delete existing "
"ones "
"to free up resources.",
nullptr,
eCommandRequiresFrame | eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched | eCommandProcessMustBePaused) {
SetHelpLong(
R"(
Examples:
(lldb) watchpoint set variable -w read_write my_global_var
)"
" Watches my_global_var for read/write access, with the region to watch \
corresponding to the byte size of the data type.");
CommandArgumentEntry arg;
CommandArgumentData var_name_arg;
// Define the only variant of this arg.
var_name_arg.arg_type = eArgTypeVarName;
var_name_arg.arg_repetition = eArgRepeatPlain;
// Push the variant into the argument entry.
arg.push_back(var_name_arg);
// Push the data for the only argument into the m_arguments vector.
m_arguments.push_back(arg);
// Absorb the '-w' and '-s' options into our option group.
m_option_group.Append(&m_option_watchpoint, LLDB_OPT_SET_1, LLDB_OPT_SET_1);
m_option_group.Finalize();
}
~CommandObjectWatchpointSetVariable() override = default;
void
HandleArgumentCompletion(CompletionRequest &request,
OptionElementVector &opt_element_vector) override {
if (request.GetCursorIndex() != 0)
return;
lldb_private::CommandCompletions::InvokeCommonCompletionCallbacks(
GetCommandInterpreter(), lldb::eVariablePathCompletion, request,
nullptr);
}
Options *GetOptions() override { return &m_option_group; }
protected:
static size_t GetVariableCallback(void *baton, const char *name,
VariableList &variable_list) {
size_t old_size = variable_list.GetSize();
Target *target = static_cast<Target *>(baton);
if (target)
target->GetImages().FindGlobalVariables(ConstString(name), UINT32_MAX,
variable_list);
return variable_list.GetSize() - old_size;
}
void DoExecute(Args &command, CommandReturnObject &result) override {
Target *target = GetDebugger().GetSelectedTarget().get();
StackFrame *frame = m_exe_ctx.GetFramePtr();
// If no argument is present, issue an error message. There's no way to
// set a watchpoint.
if (command.GetArgumentCount() <= 0) {
result.AppendError("required argument missing; "
"specify your program variable to watch for");
return;
}
// If no '-w' is specified, default to '-w modify'.
if (!m_option_watchpoint.watch_type_specified) {
m_option_watchpoint.watch_type = OptionGroupWatchpoint::eWatchModify;
}
// We passed the sanity check for the command. Proceed to set the
// watchpoint now.
lldb::addr_t addr = 0;
size_t size = 0;
VariableSP var_sp;
ValueObjectSP valobj_sp;
Stream &output_stream = result.GetOutputStream();
// A simple watch variable gesture allows only one argument.
if (command.GetArgumentCount() != 1) {
result.AppendError("specify exactly one variable to watch for");
return;
}
// Things have checked out ok...
Status error;
uint32_t expr_path_options =
StackFrame::eExpressionPathOptionCheckPtrVsMember |
StackFrame::eExpressionPathOptionsAllowDirectIVarAccess;
valobj_sp = frame->GetValueForVariableExpressionPath(
command.GetArgumentAtIndex(0), eNoDynamicValues, expr_path_options,
var_sp, error);
if (!valobj_sp) {
// Not in the frame; let's check the globals.
VariableList variable_list;
ValueObjectList valobj_list;
Status error(Variable::GetValuesForVariableExpressionPath(
command.GetArgumentAtIndex(0),
m_exe_ctx.GetBestExecutionContextScope(), GetVariableCallback, target,
variable_list, valobj_list));
if (valobj_list.GetSize())
valobj_sp = valobj_list.GetValueObjectAtIndex(0);
}
CompilerType compiler_type;
if (valobj_sp) {
AddressType addr_type;
addr = valobj_sp->GetAddressOf(false, &addr_type);
if (addr_type == eAddressTypeLoad) {
// We're in business.
// Find out the size of this variable.
size = m_option_watchpoint.watch_size.GetCurrentValue() == 0
? valobj_sp->GetByteSize().value_or(0)
: m_option_watchpoint.watch_size.GetCurrentValue();
}
compiler_type = valobj_sp->GetCompilerType();
} else {
const char *error_cstr = error.AsCString(nullptr);
if (error_cstr)
result.AppendError(error_cstr);
else
result.AppendErrorWithFormat("unable to find any variable "
"expression path that matches '%s'",
command.GetArgumentAtIndex(0));
return;
}
// Now it's time to create the watchpoint.
uint32_t watch_type = 0;
switch (m_option_watchpoint.watch_type) {
case OptionGroupWatchpoint::eWatchModify:
watch_type |= LLDB_WATCH_TYPE_MODIFY;
break;
case OptionGroupWatchpoint::eWatchRead:
watch_type |= LLDB_WATCH_TYPE_READ;
break;
case OptionGroupWatchpoint::eWatchReadWrite:
watch_type |= LLDB_WATCH_TYPE_READ | LLDB_WATCH_TYPE_WRITE;
break;
case OptionGroupWatchpoint::eWatchWrite:
watch_type |= LLDB_WATCH_TYPE_WRITE;
break;
case OptionGroupWatchpoint::eWatchInvalid:
break;
};
error.Clear();
WatchpointSP watch_sp =
target->CreateWatchpoint(addr, size, &compiler_type, watch_type, error);
if (!watch_sp) {
result.AppendErrorWithFormat(
"Watchpoint creation failed (addr=0x%" PRIx64 ", size=%" PRIu64
", variable expression='%s').\n",
addr, static_cast<uint64_t>(size), command.GetArgumentAtIndex(0));
if (const char *error_message = error.AsCString(nullptr))
result.AppendError(error_message);
return;
}
watch_sp->SetWatchSpec(command.GetArgumentAtIndex(0));
watch_sp->SetWatchVariable(true);
if (var_sp) {
if (var_sp->GetDeclaration().GetFile()) {
StreamString ss;
// True to show fullpath for declaration file.
var_sp->GetDeclaration().DumpStopContext(&ss, true);
watch_sp->SetDeclInfo(std::string(ss.GetString()));
}
if (var_sp->GetScope() == eValueTypeVariableLocal)
watch_sp->SetupVariableWatchpointDisabler(m_exe_ctx.GetFrameSP());
}
output_stream.Printf("Watchpoint created: ");
watch_sp->GetDescription(&output_stream, lldb::eDescriptionLevelFull);
output_stream.EOL();
result.SetStatus(eReturnStatusSuccessFinishResult);
}
private:
OptionGroupOptions m_option_group;
OptionGroupWatchpoint m_option_watchpoint;
};
// CommandObjectWatchpointSetExpression
#pragma mark Set
class CommandObjectWatchpointSetExpression : public CommandObjectRaw {
public:
CommandObjectWatchpointSetExpression(CommandInterpreter &interpreter)
: CommandObjectRaw(
interpreter, "watchpoint set expression",
"Set a watchpoint on an address by supplying an expression. "
"Use the '-l' option to specify the language of the expression. "
"Use the '-w' option to specify the type of watchpoint and "
"the '-s' option to specify the byte size to watch for. "
"If no '-w' option is specified, it defaults to modify. "
"If no '-s' option is specified, it defaults to the target's "
"pointer byte size. "
"Note that there are limited hardware resources for watchpoints. "
"If watchpoint setting fails, consider disable/delete existing "
"ones "
"to free up resources.",
"",
eCommandRequiresFrame | eCommandTryTargetAPILock |
eCommandProcessMustBeLaunched | eCommandProcessMustBePaused) {
SetHelpLong(
R"(
Examples:
(lldb) watchpoint set expression -w modify -s 1 -- foo + 32
Watches write access for the 1-byte region pointed to by the address 'foo + 32')");
CommandArgumentEntry arg;
CommandArgumentData expression_arg;
// Define the only variant of this arg.
expression_arg.arg_type = eArgTypeExpression;
expression_arg.arg_repetition = eArgRepeatPlain;
// Push the only variant into the argument entry.
arg.push_back(expression_arg);
// Push the data for the only argument into the m_arguments vector.
m_arguments.push_back(arg);
// Absorb the '-w' and '-s' options into our option group.
m_option_group.Append(&m_option_watchpoint, LLDB_OPT_SET_ALL,
LLDB_OPT_SET_1);
m_option_group.Finalize();
}
~CommandObjectWatchpointSetExpression() override = default;
// Overrides base class's behavior where WantsCompletion =
// !WantsRawCommandString.
bool WantsCompletion() override { return true; }
Options *GetOptions() override { return &m_option_group; }
protected:
void DoExecute(llvm::StringRef raw_command,
CommandReturnObject &result) override {
auto exe_ctx = GetCommandInterpreter().GetExecutionContext();
m_option_group.NotifyOptionParsingStarting(
&exe_ctx); // This is a raw command, so notify the option group
Target *target = GetDebugger().GetSelectedTarget().get();
StackFrame *frame = m_exe_ctx.GetFramePtr();
OptionsWithRaw args(raw_command);
llvm::StringRef expr = args.GetRawPart();
if (args.HasArgs())
if (!ParseOptionsAndNotify(args.GetArgs(), result, m_option_group,
exe_ctx))
return;
// If no argument is present, issue an error message. There's no way to
// set a watchpoint.
if (raw_command.trim().empty()) {
result.AppendError("required argument missing; specify an expression "
"to evaluate into the address to watch for");
return;
}
// If no '-w' is specified, default to '-w write'.
if (!m_option_watchpoint.watch_type_specified) {
m_option_watchpoint.watch_type = OptionGroupWatchpoint::eWatchModify;
}
// We passed the sanity check for the command. Proceed to set the
// watchpoint now.
lldb::addr_t addr = 0;
size_t size = 0;
ValueObjectSP valobj_sp;
// Use expression evaluation to arrive at the address to watch.
EvaluateExpressionOptions options;
options.SetCoerceToId(false);
options.SetUnwindOnError(true);
options.SetKeepInMemory(false);
options.SetTryAllThreads(true);
options.SetTimeout(std::nullopt);
if (m_option_watchpoint.language_type != eLanguageTypeUnknown)
options.SetLanguage(m_option_watchpoint.language_type);
ExpressionResults expr_result =
target->EvaluateExpression(expr, frame, valobj_sp, options);
if (expr_result != eExpressionCompleted) {
result.AppendError("expression evaluation of address to watch failed");
result.AppendErrorWithFormat("expression evaluated: \n%s", expr.data());
if (valobj_sp && !valobj_sp->GetError().Success())
result.AppendError(valobj_sp->GetError().AsCString());
return;
}
// Get the address to watch.
bool success = false;
addr = valobj_sp->GetValueAsUnsigned(0, &success);
if (!success) {
result.AppendError("expression did not evaluate to an address");
return;
}
if (m_option_watchpoint.watch_size.GetCurrentValue() != 0)
size = m_option_watchpoint.watch_size.GetCurrentValue();
else
size = target->GetArchitecture().GetAddressByteSize();
// Now it's time to create the watchpoint.
uint32_t watch_type;
switch (m_option_watchpoint.watch_type) {
case OptionGroupWatchpoint::eWatchRead:
watch_type = LLDB_WATCH_TYPE_READ;
break;
case OptionGroupWatchpoint::eWatchWrite:
watch_type = LLDB_WATCH_TYPE_WRITE;
break;
case OptionGroupWatchpoint::eWatchModify:
watch_type = LLDB_WATCH_TYPE_MODIFY;
break;
case OptionGroupWatchpoint::eWatchReadWrite:
watch_type = LLDB_WATCH_TYPE_READ | LLDB_WATCH_TYPE_WRITE;
break;
default:
watch_type = LLDB_WATCH_TYPE_MODIFY;
}
// Fetch the type from the value object, the type of the watched object is
// the pointee type
/// of the expression, so convert to that if we found a valid type.
CompilerType compiler_type(valobj_sp->GetCompilerType());
Status error;
WatchpointSP watch_sp =
target->CreateWatchpoint(addr, size, &compiler_type, watch_type, error);
if (watch_sp) {
watch_sp->SetWatchSpec(std::string(expr));
Stream &output_stream = result.GetOutputStream();
output_stream.Printf("Watchpoint created: ");
watch_sp->GetDescription(&output_stream, lldb::eDescriptionLevelFull);
output_stream.EOL();
result.SetStatus(eReturnStatusSuccessFinishResult);
} else {
result.AppendErrorWithFormat("Watchpoint creation failed (addr=0x%" PRIx64
", size=%" PRIu64 ").\n",
addr, (uint64_t)size);
if (error.AsCString(nullptr))
result.AppendError(error.AsCString());
}
}
private:
OptionGroupOptions m_option_group;
OptionGroupWatchpoint m_option_watchpoint;
};
// CommandObjectWatchpointSet
#pragma mark Set
class CommandObjectWatchpointSet : public CommandObjectMultiword {
public:
CommandObjectWatchpointSet(CommandInterpreter &interpreter)
: CommandObjectMultiword(
interpreter, "watchpoint set", "Commands for setting a watchpoint.",
"watchpoint set <subcommand> [<subcommand-options>]") {
LoadSubCommand(
"variable",
CommandObjectSP(new CommandObjectWatchpointSetVariable(interpreter)));
LoadSubCommand(
"expression",
CommandObjectSP(new CommandObjectWatchpointSetExpression(interpreter)));
}
~CommandObjectWatchpointSet() override = default;
};
// CommandObjectMultiwordWatchpoint
#pragma mark MultiwordWatchpoint
CommandObjectMultiwordWatchpoint::CommandObjectMultiwordWatchpoint(
CommandInterpreter &interpreter)
: CommandObjectMultiword(interpreter, "watchpoint",
"Commands for operating on watchpoints.",
"watchpoint <subcommand> [<command-options>]") {
CommandObjectSP list_command_object(
new CommandObjectWatchpointList(interpreter));
CommandObjectSP enable_command_object(
new CommandObjectWatchpointEnable(interpreter));
CommandObjectSP disable_command_object(
new CommandObjectWatchpointDisable(interpreter));
CommandObjectSP delete_command_object(
new CommandObjectWatchpointDelete(interpreter));
CommandObjectSP ignore_command_object(
new CommandObjectWatchpointIgnore(interpreter));
CommandObjectSP command_command_object(
new CommandObjectWatchpointCommand(interpreter));
CommandObjectSP modify_command_object(
new CommandObjectWatchpointModify(interpreter));
CommandObjectSP set_command_object(
new CommandObjectWatchpointSet(interpreter));
list_command_object->SetCommandName("watchpoint list");
enable_command_object->SetCommandName("watchpoint enable");
disable_command_object->SetCommandName("watchpoint disable");
delete_command_object->SetCommandName("watchpoint delete");
ignore_command_object->SetCommandName("watchpoint ignore");
command_command_object->SetCommandName("watchpoint command");
modify_command_object->SetCommandName("watchpoint modify");
set_command_object->SetCommandName("watchpoint set");
LoadSubCommand("list", list_command_object);
LoadSubCommand("enable", enable_command_object);
LoadSubCommand("disable", disable_command_object);
LoadSubCommand("delete", delete_command_object);
LoadSubCommand("ignore", ignore_command_object);
LoadSubCommand("command", command_command_object);
LoadSubCommand("modify", modify_command_object);
LoadSubCommand("set", set_command_object);
}
CommandObjectMultiwordWatchpoint::~CommandObjectMultiwordWatchpoint() = default;