llvm-project/lldb/source/Breakpoint/Watchpoint.cpp

491 lines
13 KiB
C++

//===-- Watchpoint.cpp ------------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "lldb/Breakpoint/Watchpoint.h"
// C Includes
// C++ Includes
// Other libraries and framework includes
// Project includes
#include "lldb/Breakpoint/StoppointCallbackContext.h"
#include "lldb/Core/Stream.h"
#include "lldb/Core/Value.h"
#include "lldb/Core/ValueObject.h"
#include "lldb/Core/ValueObjectMemory.h"
#include "lldb/Symbol/ClangASTContext.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/ThreadSpec.h"
#include "lldb/Expression/ClangUserExpression.h"
using namespace lldb;
using namespace lldb_private;
Watchpoint::Watchpoint (Target& target, lldb::addr_t addr, uint32_t size, const ClangASTType *type, bool hardware) :
StoppointLocation (0, addr, size, hardware),
m_target(target),
m_enabled(false),
m_is_hardware(hardware),
m_is_watch_variable(false),
m_is_ephemeral(false),
m_disabled_count(0),
m_watch_read(0),
m_watch_write(0),
m_watch_was_read(0),
m_watch_was_written(0),
m_ignore_count(0),
m_false_alarms(0),
m_decl_str(),
m_watch_spec_str(),
m_type(),
m_error(),
m_options (),
m_being_created(true)
{
if (type && type->IsValid())
m_type = *type;
else
{
// If we don't have a known type, then we force it to unsigned int of the right size.
ClangASTContext *ast_context = target.GetScratchClangASTContext();
clang_type_t clang_type = ast_context->GetBuiltinTypeForEncodingAndBitSize(eEncodingUint, 8 * size);
m_type.SetClangType(ast_context->getASTContext(), clang_type);
}
// Set the initial value of the watched variable:
if (m_target.GetProcessSP())
{
ExecutionContext exe_ctx;
m_target.GetProcessSP()->CalculateExecutionContext(exe_ctx);
CaptureWatchedValue (exe_ctx);
}
m_being_created = false;
}
Watchpoint::~Watchpoint()
{
}
// This function is used when "baton" doesn't need to be freed
void
Watchpoint::SetCallback (WatchpointHitCallback callback, void *baton, bool is_synchronous)
{
// The default "Baton" class will keep a copy of "baton" and won't free
// or delete it when it goes goes out of scope.
m_options.SetCallback(callback, BatonSP (new Baton(baton)), is_synchronous);
SendWatchpointChangedEvent (eWatchpointEventTypeCommandChanged);
}
// This function is used when a baton needs to be freed and therefore is
// contained in a "Baton" subclass.
void
Watchpoint::SetCallback (WatchpointHitCallback callback, const BatonSP &callback_baton_sp, bool is_synchronous)
{
m_options.SetCallback(callback, callback_baton_sp, is_synchronous);
SendWatchpointChangedEvent (eWatchpointEventTypeCommandChanged);
}
void
Watchpoint::ClearCallback ()
{
m_options.ClearCallback ();
SendWatchpointChangedEvent (eWatchpointEventTypeCommandChanged);
}
void
Watchpoint::SetDeclInfo (const std::string &str)
{
m_decl_str = str;
return;
}
std::string
Watchpoint::GetWatchSpec()
{
return m_watch_spec_str;
}
void
Watchpoint::SetWatchSpec (const std::string &str)
{
m_watch_spec_str = str;
return;
}
// Override default impl of StoppointLocation::IsHardware() since m_is_hardware
// member field is more accurate.
bool
Watchpoint::IsHardware () const
{
return m_is_hardware;
}
bool
Watchpoint::IsWatchVariable() const
{
return m_is_watch_variable;
}
void
Watchpoint::SetWatchVariable(bool val)
{
m_is_watch_variable = val;
}
bool
Watchpoint::CaptureWatchedValue (const ExecutionContext &exe_ctx)
{
ConstString watch_name("$__lldb__watch_value");
m_old_value_sp = m_new_value_sp;
Address watch_address(GetLoadAddress());
if (!m_type.IsValid())
{
// Don't know how to report new & old values, since we couldn't make a scalar type for this watchpoint.
// This works around an assert in ValueObjectMemory::Create.
// FIXME: This should not happen, but if it does in some case we care about,
// we can go grab the value raw and print it as unsigned.
return false;
}
m_new_value_sp = ValueObjectMemory::Create (exe_ctx.GetBestExecutionContextScope(), watch_name.AsCString(), watch_address, m_type);
m_new_value_sp = m_new_value_sp->CreateConstantValue(watch_name);
if (m_new_value_sp && m_new_value_sp->GetError().Success())
return true;
else
return false;
}
void
Watchpoint::IncrementFalseAlarmsAndReviseHitCount()
{
++m_false_alarms;
if (m_false_alarms)
{
if (m_hit_count >= m_false_alarms)
{
m_hit_count -= m_false_alarms;
m_false_alarms = 0;
}
else
{
m_false_alarms -= m_hit_count;
m_hit_count = 0;
}
}
}
// RETURNS - true if we should stop at this breakpoint, false if we
// should continue.
bool
Watchpoint::ShouldStop (StoppointCallbackContext *context)
{
IncrementHitCount();
if (!IsEnabled())
return false;
if (GetHitCount() <= GetIgnoreCount())
return false;
return true;
}
void
Watchpoint::GetDescription (Stream *s, lldb::DescriptionLevel level)
{
DumpWithLevel(s, level);
return;
}
void
Watchpoint::Dump(Stream *s) const
{
DumpWithLevel(s, lldb::eDescriptionLevelBrief);
}
// If prefix is NULL, we display the watch id and ignore the prefix altogether.
void
Watchpoint::DumpSnapshots(Stream *s, const char *prefix) const
{
if (!prefix)
{
s->Printf("\nWatchpoint %u hit:", GetID());
prefix = "";
}
if (m_old_value_sp)
{
s->Printf("\n%sold value: %s", prefix, m_old_value_sp->GetValueAsCString());
}
if (m_new_value_sp)
{
s->Printf("\n%snew value: %s", prefix, m_new_value_sp->GetValueAsCString());
}
}
void
Watchpoint::DumpWithLevel(Stream *s, lldb::DescriptionLevel description_level) const
{
if (s == NULL)
return;
assert(description_level >= lldb::eDescriptionLevelBrief &&
description_level <= lldb::eDescriptionLevelVerbose);
s->Printf("Watchpoint %u: addr = 0x%8.8" PRIx64 " size = %u state = %s type = %s%s",
GetID(),
GetLoadAddress(),
m_byte_size,
IsEnabled() ? "enabled" : "disabled",
m_watch_read ? "r" : "",
m_watch_write ? "w" : "");
if (description_level >= lldb::eDescriptionLevelFull) {
if (!m_decl_str.empty())
s->Printf("\n declare @ '%s'", m_decl_str.c_str());
if (!m_watch_spec_str.empty())
s->Printf("\n watchpoint spec = '%s'", m_watch_spec_str.c_str());
// Dump the snapshots we have taken.
DumpSnapshots(s, " ");
if (GetConditionText())
s->Printf("\n condition = '%s'", GetConditionText());
m_options.GetCallbackDescription(s, description_level);
}
if (description_level >= lldb::eDescriptionLevelVerbose)
{
s->Printf("\n hw_index = %i hit_count = %-4u ignore_count = %-4u",
GetHardwareIndex(),
GetHitCount(),
GetIgnoreCount());
}
}
bool
Watchpoint::IsEnabled() const
{
return m_enabled;
}
// Within StopInfo.cpp, we purposely turn on the ephemeral mode right before temporarily disable the watchpoint
// in order to perform possible watchpoint actions without triggering further watchpoint events.
// After the temporary disabled watchpoint is enabled, we then turn off the ephemeral mode.
void
Watchpoint::TurnOnEphemeralMode()
{
m_is_ephemeral = true;
}
void
Watchpoint::TurnOffEphemeralMode()
{
m_is_ephemeral = false;
// Leaving ephemeral mode, reset the m_disabled_count!
m_disabled_count = 0;
}
bool
Watchpoint::IsDisabledDuringEphemeralMode()
{
return m_disabled_count > 1;
}
void
Watchpoint::SetEnabled(bool enabled, bool notify)
{
if (!enabled)
{
if (!m_is_ephemeral)
SetHardwareIndex(LLDB_INVALID_INDEX32);
else
++m_disabled_count;
// Don't clear the snapshots for now.
// Within StopInfo.cpp, we purposely do disable/enable watchpoint while performing watchpoint actions.
}
bool changed = enabled != m_enabled;
m_enabled = enabled;
if (notify && !m_is_ephemeral && changed)
SendWatchpointChangedEvent (enabled ? eWatchpointEventTypeEnabled : eWatchpointEventTypeDisabled);
}
void
Watchpoint::SetWatchpointType (uint32_t type, bool notify)
{
int old_watch_read = m_watch_read;
int old_watch_write = m_watch_write;
m_watch_read = (type & LLDB_WATCH_TYPE_READ) != 0;
m_watch_write = (type & LLDB_WATCH_TYPE_WRITE) != 0;
if (notify && (old_watch_read != m_watch_read || old_watch_write != m_watch_write))
SendWatchpointChangedEvent (eWatchpointEventTypeTypeChanged);
}
bool
Watchpoint::WatchpointRead () const
{
return m_watch_read != 0;
}
bool
Watchpoint::WatchpointWrite () const
{
return m_watch_write != 0;
}
uint32_t
Watchpoint::GetIgnoreCount () const
{
return m_ignore_count;
}
void
Watchpoint::SetIgnoreCount (uint32_t n)
{
bool changed = m_ignore_count != n;
m_ignore_count = n;
if (changed)
SendWatchpointChangedEvent (eWatchpointEventTypeIgnoreChanged);
}
bool
Watchpoint::InvokeCallback (StoppointCallbackContext *context)
{
return m_options.InvokeCallback (context, GetID());
}
void
Watchpoint::SetCondition (const char *condition)
{
if (condition == NULL || condition[0] == '\0')
{
if (m_condition_ap.get())
m_condition_ap.reset();
}
else
{
// Pass NULL for expr_prefix (no translation-unit level definitions).
m_condition_ap.reset(new ClangUserExpression (condition, NULL, lldb::eLanguageTypeUnknown, ClangUserExpression::eResultTypeAny));
}
SendWatchpointChangedEvent (eWatchpointEventTypeConditionChanged);
}
const char *
Watchpoint::GetConditionText () const
{
if (m_condition_ap.get())
return m_condition_ap->GetUserText();
else
return NULL;
}
void
Watchpoint::SendWatchpointChangedEvent (lldb::WatchpointEventType eventKind)
{
if (!m_being_created
&& GetTarget().EventTypeHasListeners(Target::eBroadcastBitWatchpointChanged))
{
WatchpointEventData *data = new Watchpoint::WatchpointEventData (eventKind, shared_from_this());
GetTarget().BroadcastEvent (Target::eBroadcastBitWatchpointChanged, data);
}
}
void
Watchpoint::SendWatchpointChangedEvent (WatchpointEventData *data)
{
if (data == NULL)
return;
if (!m_being_created
&& GetTarget().EventTypeHasListeners(Target::eBroadcastBitWatchpointChanged))
GetTarget().BroadcastEvent (Target::eBroadcastBitWatchpointChanged, data);
else
delete data;
}
Watchpoint::WatchpointEventData::WatchpointEventData (WatchpointEventType sub_type,
const WatchpointSP &new_watchpoint_sp) :
EventData (),
m_watchpoint_event (sub_type),
m_new_watchpoint_sp (new_watchpoint_sp)
{
}
Watchpoint::WatchpointEventData::~WatchpointEventData ()
{
}
const ConstString &
Watchpoint::WatchpointEventData::GetFlavorString ()
{
static ConstString g_flavor ("Watchpoint::WatchpointEventData");
return g_flavor;
}
const ConstString &
Watchpoint::WatchpointEventData::GetFlavor () const
{
return WatchpointEventData::GetFlavorString ();
}
WatchpointSP &
Watchpoint::WatchpointEventData::GetWatchpoint ()
{
return m_new_watchpoint_sp;
}
WatchpointEventType
Watchpoint::WatchpointEventData::GetWatchpointEventType () const
{
return m_watchpoint_event;
}
void
Watchpoint::WatchpointEventData::Dump (Stream *s) const
{
}
const Watchpoint::WatchpointEventData *
Watchpoint::WatchpointEventData::GetEventDataFromEvent (const Event *event)
{
if (event)
{
const EventData *event_data = event->GetData();
if (event_data && event_data->GetFlavor() == WatchpointEventData::GetFlavorString())
return static_cast <const WatchpointEventData *> (event->GetData());
}
return NULL;
}
WatchpointEventType
Watchpoint::WatchpointEventData::GetWatchpointEventTypeFromEvent (const EventSP &event_sp)
{
const WatchpointEventData *data = GetEventDataFromEvent (event_sp.get());
if (data == NULL)
return eWatchpointEventTypeInvalidType;
else
return data->GetWatchpointEventType();
}
WatchpointSP
Watchpoint::WatchpointEventData::GetWatchpointFromEvent (const EventSP &event_sp)
{
WatchpointSP wp_sp;
const WatchpointEventData *data = GetEventDataFromEvent (event_sp.get());
if (data)
wp_sp = data->m_new_watchpoint_sp;
return wp_sp;
}