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//===-- Breakpoint.h --------------------------------------------*- C++ -*-===//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#include <memory>
#include <string>
#include <unordered_set>
#include <vector>
#include "lldb/Breakpoint/BreakpointID.h"
#include "lldb/Breakpoint/BreakpointLocationCollection.h"
#include "lldb/Breakpoint/BreakpointLocationList.h"
#include "lldb/Breakpoint/BreakpointName.h"
#include "lldb/Breakpoint/BreakpointOptions.h"
#include "lldb/Breakpoint/Stoppoint.h"
#include "lldb/Breakpoint/StoppointHitCounter.h"
#include "lldb/Core/SearchFilter.h"
#include "lldb/Target/Statistics.h"
#include "lldb/Utility/Event.h"
#include "lldb/Utility/StringList.h"
#include "lldb/Utility/StructuredData.h"
namespace lldb_private {
/// \class Breakpoint Breakpoint.h "lldb/Breakpoint/Breakpoint.h" Class that
/// manages logical breakpoint setting.
/// General Outline:
/// A breakpoint has four main parts, a filter, a resolver, the list of
/// breakpoint
/// locations that have been determined for the filter/resolver pair, and
/// finally a set of options for the breakpoint.
/// \b Filter:
/// This is an object derived from SearchFilter. It manages the search for
/// breakpoint location matches through the symbols in the module list of the
/// target that owns it. It also filters out locations based on whatever
/// logic it wants.
/// \b Resolver:
/// This is an object derived from BreakpointResolver. It provides a callback
/// to the filter that will find breakpoint locations. How it does this is
/// determined by what kind of resolver it is.
/// The Breakpoint class also provides constructors for the common breakpoint
/// cases which make the appropriate filter and resolver for you.
/// \b Location List:
/// This stores the breakpoint locations that have been determined to date.
/// For a given breakpoint, there will be only one location with a given
/// address. Adding a location at an already taken address will just return
/// the location already at that address. Locations can be looked up by ID,
/// or by address.
/// \b Options:
/// This includes:
/// \b Enabled/Disabled
/// \b Ignore Count
/// \b Callback
/// \b Condition
/// Note, these options can be set on the breakpoint, and they can also be set
/// on the individual locations. The options set on the breakpoint take
/// precedence over the options set on the individual location. So for
/// instance disabling the breakpoint will cause NONE of the locations to get
/// hit. But if the breakpoint is enabled, then the location's enabled state
/// will be checked to determine whether to insert that breakpoint location.
/// Similarly, if the breakpoint condition says "stop", we won't check the
/// location's condition. But if the breakpoint condition says "continue",
/// then we will check the location for whether to actually stop or not. One
/// subtle point worth observing here is that you don't actually stop at a
/// Breakpoint, you always stop at one of its locations. So the "should stop"
/// tests are done by the location, not by the breakpoint.
class Breakpoint : public std::enable_shared_from_this<Breakpoint>,
public Stoppoint {
static ConstString GetEventIdentifier();
/// An enum specifying the match style for breakpoint settings. At present
/// only used for function name style breakpoints.
enum MatchType { Exact, Regexp, Glob };
enum class OptionNames : uint32_t { Names = 0, Hardware, LastOptionName };
static const char
static const char *GetKey(OptionNames enum_value) {
return g_option_names[static_cast<uint32_t>(enum_value)];
class BreakpointEventData : public EventData {
BreakpointEventData(lldb::BreakpointEventType sub_type,
const lldb::BreakpointSP &new_breakpoint_sp);
~BreakpointEventData() override;
static ConstString GetFlavorString();
ConstString GetFlavor() const override;
lldb::BreakpointEventType GetBreakpointEventType() const;
lldb::BreakpointSP &GetBreakpoint();
BreakpointLocationCollection &GetBreakpointLocationCollection() {
return m_locations;
void Dump(Stream *s) const override;
static lldb::BreakpointEventType
GetBreakpointEventTypeFromEvent(const lldb::EventSP &event_sp);
static lldb::BreakpointSP
GetBreakpointFromEvent(const lldb::EventSP &event_sp);
static lldb::BreakpointLocationSP
GetBreakpointLocationAtIndexFromEvent(const lldb::EventSP &event_sp,
uint32_t loc_idx);
static size_t
GetNumBreakpointLocationsFromEvent(const lldb::EventSP &event_sp);
static const BreakpointEventData *
GetEventDataFromEvent(const Event *event_sp);
lldb::BreakpointEventType m_breakpoint_event;
lldb::BreakpointSP m_new_breakpoint_sp;
BreakpointLocationCollection m_locations;
BreakpointEventData(const BreakpointEventData &) = delete;
const BreakpointEventData &operator=(const BreakpointEventData &) = delete;
// Saving & restoring breakpoints:
static lldb::BreakpointSP CreateFromStructuredData(
lldb::TargetSP target_sp, StructuredData::ObjectSP &data_object_sp,
Status &error);
static bool
SerializedBreakpointMatchesNames(StructuredData::ObjectSP &bkpt_object_sp,
std::vector<std::string> &names);
virtual StructuredData::ObjectSP SerializeToStructuredData();
static const char *GetSerializationKey() { return "Breakpoint"; }
/// Destructor.
/// The destructor is not virtual since there should be no reason to
/// subclass breakpoints. The varieties of breakpoints are specified
/// instead by providing different resolvers & filters.
~Breakpoint() override;
// Methods
/// Tell whether this breakpoint is an "internal" breakpoint. \return
/// Returns \b true if this is an internal breakpoint, \b false otherwise.
bool IsInternal() const;
/// Standard "Dump" method. At present it does nothing.
void Dump(Stream *s) override;
// The next set of methods provide ways to tell the breakpoint to update it's
// location list - usually done when modules appear or disappear.
/// Tell this breakpoint to clear all its breakpoint sites. Done when the
/// process holding the breakpoint sites is destroyed.
void ClearAllBreakpointSites();
/// Tell this breakpoint to scan it's target's module list and resolve any
/// new locations that match the breakpoint's specifications.
void ResolveBreakpoint();
/// Tell this breakpoint to scan a given module list and resolve any new
/// locations that match the breakpoint's specifications.
/// \param[in] module_list
/// The list of modules to look in for new locations.
/// \param[in] send_event
/// If \b true, send a breakpoint location added event for non-internal
/// breakpoints.
void ResolveBreakpointInModules(ModuleList &module_list,
bool send_event = true);
/// Tell this breakpoint to scan a given module list and resolve any new
/// locations that match the breakpoint's specifications.
/// \param[in] module_list
/// The list of modules to look in for new locations.
/// \param[in] new_locations
/// Fills new_locations with the new locations that were made.
void ResolveBreakpointInModules(ModuleList &module_list,
BreakpointLocationCollection &new_locations);
/// Like ResolveBreakpointInModules, but allows for "unload" events, in
/// which case we will remove any locations that are in modules that got
/// unloaded.
/// \param[in] changed_modules
/// The list of modules to look in for new locations.
/// \param[in] load_event
/// If \b true then the modules were loaded, if \b false, unloaded.
/// \param[in] delete_locations
/// If \b true then the modules were unloaded delete any locations in the
/// changed modules.
void ModulesChanged(ModuleList &changed_modules, bool load_event,
bool delete_locations = false);
/// Tells the breakpoint the old module \a old_module_sp has been replaced
/// by new_module_sp (usually because the underlying file has been rebuilt,
/// and the old version is gone.)
/// \param[in] old_module_sp
/// The old module that is going away.
/// \param[in] new_module_sp
/// The new module that is replacing it.
void ModuleReplaced(lldb::ModuleSP old_module_sp,
lldb::ModuleSP new_module_sp);
// The next set of methods provide access to the breakpoint locations for
// this breakpoint.
/// Add a location to the breakpoint's location list. This is only meant to
/// be called by the breakpoint's resolver. FIXME: how do I ensure that?
/// \param[in] addr
/// The Address specifying the new location.
/// \param[out] new_location
/// Set to \b true if a new location was created, to \b false if there
/// already was a location at this Address.
/// \return
/// Returns a pointer to the new location.
lldb::BreakpointLocationSP AddLocation(const Address &addr,
bool *new_location = nullptr);
/// Find a breakpoint location by Address.
/// \param[in] addr
/// The Address specifying the location.
/// \return
/// Returns a shared pointer to the location at \a addr. The pointer
/// in the shared pointer will be nullptr if there is no location at that
/// address.
lldb::BreakpointLocationSP FindLocationByAddress(const Address &addr);
/// Find a breakpoint location ID by Address.
/// \param[in] addr
/// The Address specifying the location.
/// \return
/// Returns the UID of the location at \a addr, or \b LLDB_INVALID_ID if
/// there is no breakpoint location at that address.
lldb::break_id_t FindLocationIDByAddress(const Address &addr);
/// Find a breakpoint location for a given breakpoint location ID.
/// \param[in] bp_loc_id
/// The ID specifying the location.
/// \return
/// Returns a shared pointer to the location with ID \a bp_loc_id. The
/// pointer
/// in the shared pointer will be nullptr if there is no location with that
/// ID.
lldb::BreakpointLocationSP FindLocationByID(lldb::break_id_t bp_loc_id);
/// Get breakpoint locations by index.
/// \param[in] index
/// The location index.
/// \return
/// Returns a shared pointer to the location with index \a
/// index. The shared pointer might contain nullptr if \a index is
/// greater than then number of actual locations.
lldb::BreakpointLocationSP GetLocationAtIndex(size_t index);
/// Removes all invalid breakpoint locations.
/// Removes all breakpoint locations with architectures that aren't
/// compatible with \a arch. Also remove any breakpoint locations with whose
/// locations have address where the section has been deleted (module and
/// object files no longer exist).
/// This is typically used after the process calls exec, or anytime the
/// architecture of the target changes.
/// \param[in] arch
/// If valid, check the module in each breakpoint to make sure
/// they are compatible, otherwise, ignore architecture.
void RemoveInvalidLocations(const ArchSpec &arch);
// The next section deals with various breakpoint options.
/// If \a enable is \b true, enable the breakpoint, if \b false disable it.
void SetEnabled(bool enable) override;
/// Check the Enable/Disable state.
/// \return
/// \b true if the breakpoint is enabled, \b false if disabled.
bool IsEnabled() override;
/// Set the breakpoint to ignore the next \a count breakpoint hits.
/// \param[in] count
/// The number of breakpoint hits to ignore.
void SetIgnoreCount(uint32_t count);
/// Return the current ignore count/
/// \return
/// The number of breakpoint hits to be ignored.
uint32_t GetIgnoreCount() const;
/// Return the current hit count for all locations. \return
/// The current hit count for all locations.
uint32_t GetHitCount() const;
/// If \a one_shot is \b true, breakpoint will be deleted on first hit.
void SetOneShot(bool one_shot);
/// Check the OneShot state.
/// \return
/// \b true if the breakpoint is one shot, \b false otherwise.
bool IsOneShot() const;
/// If \a auto_continue is \b true, breakpoint will auto-continue when on
/// hit.
void SetAutoContinue(bool auto_continue);
/// Check the AutoContinue state.
/// \return
/// \b true if the breakpoint is set to auto-continue, \b false otherwise.
bool IsAutoContinue() const;
/// Set the valid thread to be checked when the breakpoint is hit.
/// \param[in] thread_id
/// If this thread hits the breakpoint, we stop, otherwise not.
void SetThreadID(lldb::tid_t thread_id);
/// Return the current stop thread value.
/// \return
/// The thread id for which the breakpoint hit will stop,
/// LLDB_INVALID_THREAD_ID for all threads.
lldb::tid_t GetThreadID() const;
void SetThreadIndex(uint32_t index);
uint32_t GetThreadIndex() const;
void SetThreadName(const char *thread_name);
const char *GetThreadName() const;
void SetQueueName(const char *queue_name);
const char *GetQueueName() const;
/// Set the callback action invoked when the breakpoint is hit.
/// \param[in] callback
/// The method that will get called when the breakpoint is hit.
/// \param[in] baton
/// A void * pointer that will get passed back to the callback function.
/// \param[in] is_synchronous
/// If \b true the callback will be run on the private event thread
/// before the stop event gets reported. If false, the callback will get
/// handled on the public event thread after the stop has been posted.
void SetCallback(BreakpointHitCallback callback, void *baton,
bool is_synchronous = false);
void SetCallback(BreakpointHitCallback callback,
const lldb::BatonSP &callback_baton_sp,
bool is_synchronous = false);
void ClearCallback();
/// Set the breakpoint's condition.
/// \param[in] condition
/// The condition expression to evaluate when the breakpoint is hit.
/// Pass in nullptr to clear the condition.
void SetCondition(const char *condition);
/// Return a pointer to the text of the condition expression.
/// \return
/// A pointer to the condition expression text, or nullptr if no
// condition has been set.
const char *GetConditionText() const;
// The next section are various utility functions.
/// Return the number of breakpoint locations that have resolved to actual
/// breakpoint sites.
/// \return
/// The number locations resolved breakpoint sites.
size_t GetNumResolvedLocations() const;
/// Return whether this breakpoint has any resolved locations.
/// \return
/// True if GetNumResolvedLocations > 0
bool HasResolvedLocations() const;
/// Return the number of breakpoint locations.
/// \return
/// The number breakpoint locations.
size_t GetNumLocations() const;
/// Put a description of this breakpoint into the stream \a s.
/// \param[in] s
/// Stream into which to dump the description.
/// \param[in] level
/// The description level that indicates the detail level to
/// provide.
/// \see lldb::DescriptionLevel
void GetDescription(Stream *s, lldb::DescriptionLevel level,
bool show_locations = false);
/// Set the "kind" description for a breakpoint. If the breakpoint is hit
/// the stop info will show this "kind" description instead of the
/// breakpoint number. Mostly useful for internal breakpoints, where the
/// breakpoint number doesn't have meaning to the user.
/// \param[in] kind
/// New "kind" description.
void SetBreakpointKind(const char *kind) { m_kind_description.assign(kind); }
/// Return the "kind" description for a breakpoint.
/// \return
/// The breakpoint kind, or nullptr if none is set.
const char *GetBreakpointKind() const { return m_kind_description.c_str(); }
/// Accessor for the breakpoint Target.
/// \return
/// This breakpoint's Target.
Target &GetTarget() { return m_target; }
const Target &GetTarget() const { return m_target; }
const lldb::TargetSP GetTargetSP();
void GetResolverDescription(Stream *s);
/// Find breakpoint locations which match the (filename, line_number)
/// description. The breakpoint location collection is to be filled with the
/// matching locations. It should be initialized with 0 size by the API
/// client.
/// \return
/// True if there is a match
/// The locations which match the filename and line_number in loc_coll.
/// If its
/// size is 0 and true is returned, it means the breakpoint fully matches
/// the
/// description.
bool GetMatchingFileLine(ConstString filename, uint32_t line_number,
BreakpointLocationCollection &loc_coll);
void GetFilterDescription(Stream *s);
/// Returns the BreakpointOptions structure set at the breakpoint level.
/// Meant to be used by the BreakpointLocation class.
/// \return
/// A reference to this breakpoint's BreakpointOptions.
BreakpointOptions &GetOptions();
/// Returns the BreakpointOptions structure set at the breakpoint level.
/// Meant to be used by the BreakpointLocation class.
/// \return
/// A reference to this breakpoint's BreakpointOptions.
const BreakpointOptions &GetOptions() const;
/// Invoke the callback action when the breakpoint is hit.
/// Meant to be used by the BreakpointLocation class.
/// \param[in] context
/// Described the breakpoint event.
/// \param[in] bp_loc_id
/// Which breakpoint location hit this breakpoint.
/// \return
/// \b true if the target should stop at this breakpoint and \b false not.
bool InvokeCallback(StoppointCallbackContext *context,
lldb::break_id_t bp_loc_id);
bool IsHardware() const { return m_hardware; }
lldb::BreakpointResolverSP GetResolver() { return m_resolver_sp; }
lldb::SearchFilterSP GetSearchFilter() { return m_filter_sp; }
private: // The target needs to manage adding & removing names. It will do the
// checking for name validity as well.
bool AddName(llvm::StringRef new_name);
void RemoveName(const char *name_to_remove) {
if (name_to_remove)
bool MatchesName(const char *name) {
return m_name_list.find(name) != m_name_list.end();
void GetNames(std::vector<std::string> &names) {
for (auto name : m_name_list) {
/// Set a pre-condition filter that overrides all user provided
/// filters/callbacks etc.
/// Used to define fancy breakpoints that can do dynamic hit detection
/// without taking up the condition slot - which really belongs to the user
/// anyway...
/// The Precondition should not continue the target, it should return true
/// if the condition says to stop and false otherwise.
void SetPrecondition(lldb::BreakpointPreconditionSP precondition_sp) {
m_precondition_sp = std::move(precondition_sp);
bool EvaluatePrecondition(StoppointCallbackContext &context);
lldb::BreakpointPreconditionSP GetPrecondition() { return m_precondition_sp; }
// Produces the OR'ed values for all the names assigned to this breakpoint.
const BreakpointName::Permissions &GetPermissions() const {
return m_permissions;
BreakpointName::Permissions &GetPermissions() {
return m_permissions;
bool AllowList() const {
return GetPermissions().GetAllowList();
bool AllowDisable() const {
return GetPermissions().GetAllowDisable();
bool AllowDelete() const {
return GetPermissions().GetAllowDelete();
// This one should only be used by Target to copy breakpoints from target to
// target - primarily from the dummy target to prime new targets.
static lldb::BreakpointSP CopyFromBreakpoint(lldb::TargetSP new_target,
const Breakpoint &bp_to_copy_from);
/// Get statistics associated with this breakpoint in JSON format.
llvm::json::Value GetStatistics();
/// Get the time it took to resolve all locations in this breakpoint.
StatsDuration GetResolveTime() const { return m_resolve_time; }
friend class Target;
// Protected Methods
/// Constructors and Destructors
/// Only the Target can make a breakpoint, and it owns the breakpoint
/// lifespans. The constructor takes a filter and a resolver. Up in Target
/// there are convenience variants that make breakpoints for some common
/// cases.
/// \param[in] target
/// The target in which the breakpoint will be set.
/// \param[in] filter_sp
/// Shared pointer to the search filter that restricts the search domain of
/// the breakpoint.
/// \param[in] resolver_sp
/// Shared pointer to the resolver object that will determine breakpoint
/// matches.
/// \param hardware
/// If true, request a hardware breakpoint to be used to implement the
/// breakpoint locations.
/// \param resolve_indirect_symbols
/// If true, and the address of a given breakpoint location in this
/// breakpoint is set on an
/// indirect symbol (i.e. Symbol::IsIndirect returns true) then the actual
/// breakpoint site will
/// be set on the target of the indirect symbol.
// This is the generic constructor
Breakpoint(Target &target, lldb::SearchFilterSP &filter_sp,
lldb::BreakpointResolverSP &resolver_sp, bool hardware,
bool resolve_indirect_symbols = true);
friend class BreakpointLocation; // To call the following two when determining
// whether to stop.
void DecrementIgnoreCount();
// To call from CopyFromBreakpoint.
Breakpoint(Target &new_target, const Breakpoint &bp_to_copy_from);
// For Breakpoint only
bool m_being_created;
m_hardware; // If this breakpoint is required to use a hardware breakpoint
Target &m_target; // The target that holds this breakpoint.
std::unordered_set<std::string> m_name_list; // If not empty, this is the name
// of this breakpoint (many
// breakpoints can share the same
// name.)
m_filter_sp; // The filter that constrains the breakpoint's domain.
m_resolver_sp; // The resolver that defines this breakpoint.
lldb::BreakpointPreconditionSP m_precondition_sp; // The precondition is a
// breakpoint-level hit
// filter that can be used
// to skip certain breakpoint hits. For instance, exception breakpoints use
// this to limit the stop to certain exception classes, while leaving the
// condition & callback free for user specification.
BreakpointOptions m_options; // Settable breakpoint options
m_locations; // The list of locations currently found for this breakpoint.
std::string m_kind_description;
bool m_resolve_indirect_symbols;
/// Number of times this breakpoint has been hit. This is kept separately
/// from the locations hit counts, since locations can go away when their
/// backing library gets unloaded, and we would lose hit counts.
StoppointHitCounter m_hit_counter;
BreakpointName::Permissions m_permissions;
StatsDuration m_resolve_time{0.0};
void SendBreakpointChangedEvent(lldb::BreakpointEventType eventKind);
void SendBreakpointChangedEvent(BreakpointEventData *data);
Breakpoint(const Breakpoint &) = delete;
const Breakpoint &operator=(const Breakpoint &) = delete;
} // namespace lldb_private