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Debugger.h
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Debugger.h
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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef vm_Debugger_h
#define vm_Debugger_h
#include "mozilla/DoublyLinkedList.h"
#include "mozilla/GuardObjects.h"
#include "mozilla/LinkedList.h"
#include "mozilla/Range.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/Vector.h"
#include "ds/TraceableFifo.h"
#include "gc/Barrier.h"
#include "gc/WeakMap.h"
#include "js/Debug.h"
#include "js/GCVariant.h"
#include "js/HashTable.h"
#include "js/Promise.h"
#include "js/Utility.h"
#include "js/Wrapper.h"
#include "proxy/DeadObjectProxy.h"
#include "vm/GlobalObject.h"
#include "vm/JSContext.h"
#include "vm/Realm.h"
#include "vm/SavedStacks.h"
#include "vm/Stack.h"
namespace js {
/**
* Tells how the JS engine should resume debuggee execution after firing a
* debugger hook. Most debugger hooks get to choose how the debuggee proceeds;
* see js/src/doc/Debugger/Conventions.md under "Resumption Values".
*
* Debugger::processHandlerResult() translates between JavaScript values and
* this enum.
*
* The values `ResumeMode::Throw` and `ResumeMode::Return` are always
* associated with a value (the exception value or return value). Sometimes
* this is represented as an explicit `JS::Value` variable or parameter,
* declared alongside the `ResumeMode`. In other cases, especially when
* ResumeMode is used as a return type (as in Debugger::onEnterFrame), the
* value is stashed in `cx`'s pending exception slot or the topmost frame's
* return value slot.
*/
enum class ResumeMode {
/**
* The debuggee should continue unchanged.
*
* This corresponds to a resumption value of `undefined`.
*/
Continue,
/**
* Throw an exception in the debuggee.
*
* This corresponds to a resumption value of `{throw: <value>}`.
*/
Throw,
/**
* Terminate the debuggee, as if it had been cancelled via the "slow
* script" ribbon.
*
* This corresponds to a resumption value of `null`.
*/
Terminate,
/**
* Force the debuggee to return from the current frame.
*
* This corresponds to a resumption value of `{return: <value>}`.
*/
Return,
};
class AbstractGeneratorObject;
class Breakpoint;
class DebuggerMemory;
class PromiseObject;
class ScriptedOnStepHandler;
class ScriptedOnPopHandler;
class WasmInstanceObject;
typedef HashSet<ReadBarrieredGlobalObject,
MovableCellHasher<ReadBarrieredGlobalObject>, ZoneAllocPolicy>
WeakGlobalObjectSet;
#ifdef DEBUG
extern void CheckDebuggeeThing(JSScript* script, bool invisibleOk);
extern void CheckDebuggeeThing(LazyScript* script, bool invisibleOk);
extern void CheckDebuggeeThing(JSObject* obj, bool invisibleOk);
#endif
/*
* A weakmap from GC thing keys to JSObject values that supports the keys being
* in different compartments to the values. All values must be in the same
* compartment.
*
* The purpose of this is to allow the garbage collector to easily find edges
* from debuggee object compartments to debugger compartments when calculating
* the compartment groups. Note that these edges are the inverse of the edges
* stored in the cross compartment map.
*
* The current implementation results in all debuggee object compartments being
* swept in the same group as the debugger. This is a conservative approach,
* and compartments may be unnecessarily grouped, however it results in a
* simpler and faster implementation.
*
* If InvisibleKeysOk is true, then the map can have keys in invisible-to-
* debugger compartments. If it is false, we assert that such entries are never
* created.
*
* Also note that keys in these weakmaps can be in any compartment, debuggee or
* not, because they are not deleted when a compartment is no longer a
* debuggee: the values need to maintain object identity across add/remove/add
* transitions. (Frames are an exception to the rule. Existing Debugger.Frame
* objects are killed when debugging is disabled for their compartment, and if
* it's re-enabled later, new Frame objects are created.)
*/
template <class UnbarrieredKey, bool InvisibleKeysOk = false>
class DebuggerWeakMap
: private WeakMap<HeapPtr<UnbarrieredKey>, HeapPtr<JSObject*>> {
private:
typedef HeapPtr<UnbarrieredKey> Key;
typedef HeapPtr<JSObject*> Value;
typedef HashMap<JS::Zone*, uintptr_t, DefaultHasher<JS::Zone*>,
ZoneAllocPolicy>
CountMap;
CountMap zoneCounts;
JS::Compartment* compartment;
public:
typedef WeakMap<Key, Value> Base;
explicit DebuggerWeakMap(JSContext* cx)
: Base(cx), zoneCounts(cx->zone()), compartment(cx->compartment()) {}
public:
// Expose those parts of HashMap public interface that are used by Debugger
// methods.
using Entry = typename Base::Entry;
using Ptr = typename Base::Ptr;
using AddPtr = typename Base::AddPtr;
using Range = typename Base::Range;
using Enum = typename Base::Enum;
using Lookup = typename Base::Lookup;
// Expose WeakMap public interface.
using Base::all;
using Base::lookup;
using Base::lookupForAdd;
using Base::remove;
using Base::trace;
template <typename KeyInput, typename ValueInput>
bool relookupOrAdd(AddPtr& p, const KeyInput& k, const ValueInput& v) {
MOZ_ASSERT(v->compartment() == this->compartment);
#ifdef DEBUG
CheckDebuggeeThing(k, InvisibleKeysOk);
#endif
MOZ_ASSERT(!Base::has(k));
if (!incZoneCount(k->zone())) {
return false;
}
bool ok = Base::relookupOrAdd(p, k, v);
if (!ok) {
decZoneCount(k->zone());
}
return ok;
}
template <typename KeyInput>
bool has(const KeyInput& k) const {
return !!this->lookup(k);
}
void remove(const Lookup& l) {
MOZ_ASSERT(Base::has(l));
Base::remove(l);
decZoneCount(l->zone());
}
// Remove entries whose keys satisfy the given predicate.
template <typename Predicate>
void removeIf(Predicate test) {
for (Enum e(*static_cast<Base*>(this)); !e.empty(); e.popFront()) {
JSObject* key = e.front().key();
if (test(key)) {
decZoneCount(key->zoneFromAnyThread());
e.removeFront();
}
}
}
public:
template <void(traceValueEdges)(JSTracer*, JSObject*)>
void traceCrossCompartmentEdges(JSTracer* tracer) {
for (Enum e(*static_cast<Base*>(this)); !e.empty(); e.popFront()) {
traceValueEdges(tracer, e.front().value());
Key key = e.front().key();
TraceEdge(tracer, &key, "Debugger WeakMap key");
if (key != e.front().key()) {
e.rekeyFront(key);
}
key.unsafeSet(nullptr);
}
}
bool hasKeyInZone(JS::Zone* zone) {
CountMap::Ptr p = zoneCounts.lookup(zone);
MOZ_ASSERT_IF(p.found(), p->value() > 0);
return p.found();
}
private:
/* Override sweep method to also update our edge cache. */
void sweep() override {
MOZ_ASSERT(CurrentThreadIsPerformingGC());
for (Enum e(*static_cast<Base*>(this)); !e.empty(); e.popFront()) {
if (gc::IsAboutToBeFinalized(&e.front().mutableKey())) {
decZoneCount(e.front().key()->zoneFromAnyThread());
e.removeFront();
}
}
#ifdef DEBUG
Base::assertEntriesNotAboutToBeFinalized();
#endif
}
MOZ_MUST_USE bool incZoneCount(JS::Zone* zone) {
CountMap::AddPtr p = zoneCounts.lookupForAdd(zone);
if (!p && !zoneCounts.add(p, zone, 0)) {
return false; // OOM'd while adding
}
++p->value();
return true;
}
void decZoneCount(JS::Zone* zone) {
CountMap::Ptr p = zoneCounts.lookup(zone);
MOZ_ASSERT(p);
MOZ_ASSERT(p->value() > 0);
--p->value();
if (p->value() == 0) {
zoneCounts.remove(zone);
}
}
#ifdef JS_GC_ZEAL
// Let the weak map marking verifier know that this map can
// contain keys in other zones.
virtual bool allowKeysInOtherZones() const override { return true; }
#endif
};
class LeaveDebuggeeNoExecute;
// Suppresses all debuggee NX checks, i.e., allow all execution. Used to allow
// certain whitelisted operations to execute code.
//
// WARNING
// WARNING Do not use this unless you know what you are doing!
// WARNING
class AutoSuppressDebuggeeNoExecuteChecks {
EnterDebuggeeNoExecute** stack_;
EnterDebuggeeNoExecute* prev_;
public:
explicit AutoSuppressDebuggeeNoExecuteChecks(JSContext* cx) {
stack_ = &cx->noExecuteDebuggerTop.ref();
prev_ = *stack_;
*stack_ = nullptr;
}
~AutoSuppressDebuggeeNoExecuteChecks() {
MOZ_ASSERT(!*stack_);
*stack_ = prev_;
}
};
class MOZ_RAII EvalOptions {
JS::UniqueChars filename_;
unsigned lineno_ = 1;
public:
EvalOptions() = default;
~EvalOptions() = default;
const char* filename() const { return filename_.get(); }
unsigned lineno() const { return lineno_; }
MOZ_MUST_USE bool setFilename(JSContext* cx, const char* filename);
void setLineno(unsigned lineno) { lineno_ = lineno; }
};
/*
* Env is the type of what ES5 calls "lexical environments" (runtime activations
* of lexical scopes). This is currently just JSObject, and is implemented by
* CallObject, LexicalEnvironmentObject, and WithEnvironmentObject, among
* others--but environments and objects are really two different concepts.
*/
typedef JSObject Env;
// One of a real JSScript, a real LazyScript, or synthesized.
//
// If synthesized, the referent is one of the following:
//
// 1. A WasmInstanceObject, denoting a synthesized toplevel wasm module
// script.
// 2. A wasm JSFunction, denoting a synthesized wasm function script.
// NYI!
typedef mozilla::Variant<JSScript*, LazyScript*, WasmInstanceObject*>
DebuggerScriptReferent;
// Either a ScriptSourceObject, for ordinary JS, or a WasmInstanceObject,
// denoting the synthesized source of a wasm module.
typedef mozilla::Variant<ScriptSourceObject*, WasmInstanceObject*>
DebuggerSourceReferent;
class Debugger : private mozilla::LinkedListElement<Debugger> {
friend class Breakpoint;
friend class DebuggerMemory;
friend struct JSRuntime::GlobalObjectWatchersLinkAccess<Debugger>;
friend class SavedStacks;
friend class ScriptedOnStepHandler;
friend class ScriptedOnPopHandler;
friend class mozilla::LinkedListElement<Debugger>;
friend class mozilla::LinkedList<Debugger>;
friend bool(::JS_DefineDebuggerObject)(JSContext* cx, JS::HandleObject obj);
friend bool(::JS::dbg::IsDebugger)(JSObject&);
friend bool(::JS::dbg::GetDebuggeeGlobals)(JSContext*, JSObject&,
AutoObjectVector&);
friend bool JS::dbg::FireOnGarbageCollectionHookRequired(JSContext* cx);
friend bool JS::dbg::FireOnGarbageCollectionHook(
JSContext* cx, JS::dbg::GarbageCollectionEvent::Ptr&& data);
public:
enum Hook {
OnDebuggerStatement,
OnExceptionUnwind,
OnNewScript,
OnEnterFrame,
OnNewGlobalObject,
OnNewPromise,
OnPromiseSettled,
OnGarbageCollection,
HookCount
};
enum {
JSSLOT_DEBUG_PROTO_START,
JSSLOT_DEBUG_FRAME_PROTO = JSSLOT_DEBUG_PROTO_START,
JSSLOT_DEBUG_ENV_PROTO,
JSSLOT_DEBUG_OBJECT_PROTO,
JSSLOT_DEBUG_SCRIPT_PROTO,
JSSLOT_DEBUG_SOURCE_PROTO,
JSSLOT_DEBUG_MEMORY_PROTO,
JSSLOT_DEBUG_PROTO_STOP,
JSSLOT_DEBUG_HOOK_START = JSSLOT_DEBUG_PROTO_STOP,
JSSLOT_DEBUG_HOOK_STOP = JSSLOT_DEBUG_HOOK_START + HookCount,
JSSLOT_DEBUG_MEMORY_INSTANCE = JSSLOT_DEBUG_HOOK_STOP,
JSSLOT_DEBUG_COUNT
};
class ExecutionObservableSet {
public:
typedef HashSet<Zone*>::Range ZoneRange;
virtual Zone* singleZone() const { return nullptr; }
virtual JSScript* singleScriptForZoneInvalidation() const {
return nullptr;
}
virtual const HashSet<Zone*>* zones() const { return nullptr; }
virtual bool shouldRecompileOrInvalidate(JSScript* script) const = 0;
virtual bool shouldMarkAsDebuggee(FrameIter& iter) const = 0;
};
// This enum is converted to and compare with bool values; NotObserving
// must be 0 and Observing must be 1.
enum IsObserving { NotObserving = 0, Observing = 1 };
// Return true if the given realm is a debuggee of this debugger,
// false otherwise.
bool isDebuggeeUnbarriered(const Realm* realm) const;
// Return true if this Debugger observed a debuggee that participated in the
// GC identified by the given GC number. Return false otherwise.
// May return false negatives if we have hit OOM.
bool observedGC(uint64_t majorGCNumber) const {
return observedGCs.has(majorGCNumber);
}
// Notify this Debugger that one or more of its debuggees is participating
// in the GC identified by the given GC number.
bool debuggeeIsBeingCollected(uint64_t majorGCNumber) {
return observedGCs.put(majorGCNumber);
}
bool isEnabled() const { return enabled; }
static SavedFrame* getObjectAllocationSite(JSObject& obj);
struct AllocationsLogEntry {
AllocationsLogEntry(HandleObject frame, mozilla::TimeStamp when,
const char* className, HandleAtom ctorName, size_t size,
bool inNursery)
: frame(frame),
when(when),
className(className),
ctorName(ctorName),
size(size),
inNursery(inNursery) {
MOZ_ASSERT_IF(frame, UncheckedUnwrap(frame)->is<SavedFrame>() ||
IsDeadProxyObject(frame));
}
HeapPtr<JSObject*> frame;
mozilla::TimeStamp when;
const char* className;
HeapPtr<JSAtom*> ctorName;
size_t size;
bool inNursery;
void trace(JSTracer* trc) {
TraceNullableEdge(trc, &frame, "Debugger::AllocationsLogEntry::frame");
TraceNullableEdge(trc, &ctorName,
"Debugger::AllocationsLogEntry::ctorName");
}
};
// Barrier methods so we can have ReadBarriered<Debugger*>.
static void readBarrier(Debugger* dbg) {
InternalBarrierMethods<JSObject*>::readBarrier(dbg->object);
}
static void writeBarrierPost(Debugger** vp, Debugger* prev, Debugger* next) {}
#ifdef DEBUG
static void assertThingIsNotGray(Debugger* dbg) { return; }
#endif
private:
GCPtrNativeObject object; /* The Debugger object. Strong reference. */
WeakGlobalObjectSet
debuggees; /* Debuggee globals. Cross-compartment weak references. */
JS::ZoneSet debuggeeZones; /* Set of zones that we have debuggees in. */
js::GCPtrObject uncaughtExceptionHook; /* Strong reference. */
bool enabled;
bool allowUnobservedAsmJS;
// Whether to enable code coverage on the Debuggee.
bool collectCoverageInfo;
template <typename T>
struct DebuggerLinkAccess {
static mozilla::DoublyLinkedListElement<T>& Get(T* aThis) {
return aThis->debuggerLink;
}
};
// List of all js::Breakpoints in this debugger.
using BreakpointList =
mozilla::DoublyLinkedList<js::Breakpoint,
DebuggerLinkAccess<js::Breakpoint>>;
BreakpointList breakpoints;
// The set of GC numbers for which one or more of this Debugger's observed
// debuggees participated in.
using GCNumberSet =
HashSet<uint64_t, DefaultHasher<uint64_t>, ZoneAllocPolicy>;
GCNumberSet observedGCs;
using AllocationsLog = js::TraceableFifo<AllocationsLogEntry>;
AllocationsLog allocationsLog;
bool trackingAllocationSites;
double allocationSamplingProbability;
size_t maxAllocationsLogLength;
bool allocationsLogOverflowed;
static const size_t DEFAULT_MAX_LOG_LENGTH = 5000;
MOZ_MUST_USE bool appendAllocationSite(JSContext* cx, HandleObject obj,
HandleSavedFrame frame,
mozilla::TimeStamp when);
/*
* Recompute the set of debuggee zones based on the set of debuggee globals.
*/
void recomputeDebuggeeZoneSet();
/*
* Return true if there is an existing object metadata callback for the
* given global's compartment that will prevent our instrumentation of
* allocations.
*/
static bool cannotTrackAllocations(const GlobalObject& global);
/*
* Return true if the given global is being observed by at least one
* Debugger that is tracking allocations.
*/
static bool isObservedByDebuggerTrackingAllocations(
const GlobalObject& global);
/*
* Add allocations tracking for objects allocated within the given
* debuggee's compartment. The given debuggee global must be observed by at
* least one Debugger that is enabled and tracking allocations.
*/
static MOZ_MUST_USE bool addAllocationsTracking(
JSContext* cx, Handle<GlobalObject*> debuggee);
/*
* Remove allocations tracking for objects allocated within the given
* global's compartment. This is a no-op if there are still Debuggers
* observing this global and who are tracking allocations.
*/
static void removeAllocationsTracking(GlobalObject& global);
/*
* Add or remove allocations tracking for all debuggees.
*/
MOZ_MUST_USE bool addAllocationsTrackingForAllDebuggees(JSContext* cx);
void removeAllocationsTrackingForAllDebuggees();
/*
* If this Debugger is enabled, and has a onNewGlobalObject handler, then
* this link is inserted into the list headed by
* JSRuntime::onNewGlobalObjectWatchers.
*/
mozilla::DoublyLinkedListElement<Debugger> onNewGlobalObjectWatchersLink;
/*
* Map from stack frames that are currently on the stack to Debugger.Frame
* instances.
*
* The keys are always live stack frames. We drop them from this map as
* soon as they leave the stack (see slowPathOnLeaveFrame) and in
* removeDebuggee.
*
* We don't trace the keys of this map (the frames are on the stack and
* thus necessarily live), but we do trace the values. It's like a WeakMap
* that way, but since stack frames are not gc-things, the implementation
* has to be different.
*/
typedef HashMap<AbstractFramePtr, HeapPtr<DebuggerFrame*>,
DefaultHasher<AbstractFramePtr>, ZoneAllocPolicy>
FrameMap;
FrameMap frames;
/*
* Map from generator objects to their Debugger.Frame instances.
*
* When a Debugger.Frame is created for a generator frame, it is added to
* this map and remains there for the lifetime of the generator, whether
* that frame is on the stack at the moment or not. This is in addition to
* the entry in `frames` that exists as long as the generator frame is on
* the stack.
*
* We need to keep the Debugger.Frame object alive to deliver it to the
* onEnterFrame handler on resume, and to retain onStep and onPop hooks.
*
* An entry is present in this table when:
* - both the debuggee generator object and the Debugger.Frame object exist
* - the Debugger.Frame's owner is still an enabled debugger of
* the debuggee compartment
* regardless of whether the frame is currently suspended. (This list is
* meant to explain why we update the table in the particular places where
* we do so.)
*/
typedef DebuggerWeakMap<JSObject*> GeneratorWeakMap;
GeneratorWeakMap generatorFrames;
/* An ephemeral map from JSScript* to Debugger.Script instances. */
typedef DebuggerWeakMap<JSScript*> ScriptWeakMap;
ScriptWeakMap scripts;
using LazyScriptWeakMap = DebuggerWeakMap<LazyScript*>;
LazyScriptWeakMap lazyScripts;
using LazyScriptVector = JS::GCVector<LazyScript*>;
// The map from debuggee source script objects to their Debugger.Source
// instances.
typedef DebuggerWeakMap<JSObject*, true> SourceWeakMap;
SourceWeakMap sources;
// The map from debuggee objects to their Debugger.Object instances.
typedef DebuggerWeakMap<JSObject*> ObjectWeakMap;
ObjectWeakMap objects;
// The map from debuggee Envs to Debugger.Environment instances.
ObjectWeakMap environments;
// The map from WasmInstanceObjects to synthesized Debugger.Script
// instances.
typedef DebuggerWeakMap<WasmInstanceObject*> WasmInstanceWeakMap;
WasmInstanceWeakMap wasmInstanceScripts;
// The map from WasmInstanceObjects to synthesized Debugger.Source
// instances.
WasmInstanceWeakMap wasmInstanceSources;
// Keep track of tracelogger last drained identifiers to know if there are
// lost events.
#ifdef NIGHTLY_BUILD
uint32_t traceLoggerLastDrainedSize;
uint32_t traceLoggerLastDrainedIteration;
#endif
uint32_t traceLoggerScriptedCallsLastDrainedSize;
uint32_t traceLoggerScriptedCallsLastDrainedIteration;
class QueryBase;
class ScriptQuery;
class SourceQuery;
class ObjectQuery;
MOZ_MUST_USE bool addDebuggeeGlobal(JSContext* cx, Handle<GlobalObject*> obj);
void removeDebuggeeGlobal(FreeOp* fop, GlobalObject* global,
WeakGlobalObjectSet::Enum* debugEnum);
enum class CallUncaughtExceptionHook { No, Yes };
/*
* Apply the resumption information in (resumeMode, vp) to `frame` in
* anticipation of returning to the debuggee.
*
* This is the usual path for returning from the debugger to the debuggee
* when we have a resumption value to apply. This does final checks on the
* result value and exits the debugger's realm by calling `ar.reset()`.
* Some hooks don't call this because they don't allow the debugger to
* control resumption; those just call `ar.reset()` and return.
*/
ResumeMode leaveDebugger(mozilla::Maybe<AutoRealm>& ar,
AbstractFramePtr frame,
const mozilla::Maybe<HandleValue>& maybeThisv,
CallUncaughtExceptionHook callHook,
ResumeMode resumeMode, MutableHandleValue vp);
/*
* Report and clear the pending exception on ar.context, if any, and return
* ResumeMode::Terminate.
*/
ResumeMode reportUncaughtException(mozilla::Maybe<AutoRealm>& ar);
/*
* Cope with an error or exception in a debugger hook.
*
* If callHook is true, then call the uncaughtExceptionHook, if any. If, in
* addition, vp is given, then parse the value returned by
* uncaughtExceptionHook as a resumption value.
*
* If there is no uncaughtExceptionHook, or if it fails, report and clear
* the pending exception on ar.context and return ResumeMode::Terminate.
*
* This always calls `ar.reset()`; ar is a parameter because this method
* must do some things in the debugger realm and some things in the
* debuggee realm.
*/
ResumeMode handleUncaughtException(mozilla::Maybe<AutoRealm>& ar);
ResumeMode handleUncaughtException(
mozilla::Maybe<AutoRealm>& ar, MutableHandleValue vp,
const mozilla::Maybe<HandleValue>& thisVForCheck = mozilla::Nothing(),
AbstractFramePtr frame = NullFramePtr());
ResumeMode handleUncaughtExceptionHelper(
mozilla::Maybe<AutoRealm>& ar, MutableHandleValue* vp,
const mozilla::Maybe<HandleValue>& thisVForCheck, AbstractFramePtr frame);
/*
* Handle the result of a hook that is expected to return a resumption
* value <https://wiki.mozilla.org/Debugger#Resumption_Values>. This is
* called when we return from a debugging hook to debuggee code. The
* interpreter wants a (ResumeMode, Value) pair telling it how to proceed.
*
* Precondition: ar is entered. We are in the debugger compartment.
*
* Postcondition: This called ar.reset(). See handleUncaughtException.
*
* If `success` is false, the hook failed. If an exception is pending in
* ar.context(), return handleUncaughtException(ar, vp, callhook).
* Otherwise just return ResumeMode::Terminate.
*
* If `success` is true, there must be no exception pending in ar.context().
* `rv` may be:
*
* undefined - Return `ResumeMode::Continue` to continue execution
* normally.
*
* {return: value} or {throw: value} - Call unwrapDebuggeeValue to
* unwrap `value`. Store the result in `*vp` and return
* `ResumeMode::Return` or `ResumeMode::Throw`. The interpreter
* will force the current frame to return or throw an exception.
*
* null - Return `ResumeMode::Terminate` to terminate the debuggee with
* an uncatchable error.
*
* anything else - Make a new TypeError the pending exception and
* return handleUncaughtException(ar, vp, callHook).
*/
ResumeMode processHandlerResult(mozilla::Maybe<AutoRealm>& ar, bool success,
const Value& rv, AbstractFramePtr frame,
jsbytecode* pc, MutableHandleValue vp);
ResumeMode processParsedHandlerResult(mozilla::Maybe<AutoRealm>& ar,
AbstractFramePtr frame, jsbytecode* pc,
bool success, ResumeMode resumeMode,
MutableHandleValue vp);
GlobalObject* unwrapDebuggeeArgument(JSContext* cx, const Value& v);
static void traceObject(JSTracer* trc, JSObject* obj);
void trace(JSTracer* trc);
friend struct js::GCManagedDeletePolicy<Debugger>;
void traceForMovingGC(JSTracer* trc);
void traceCrossCompartmentEdges(JSTracer* tracer);
static const ClassOps classOps_;
public:
static const Class class_;
private:
static MOZ_MUST_USE bool getHookImpl(JSContext* cx, CallArgs& args,
Debugger& dbg, Hook which);
static MOZ_MUST_USE bool setHookImpl(JSContext* cx, CallArgs& args,
Debugger& dbg, Hook which);
static bool getEnabled(JSContext* cx, unsigned argc, Value* vp);
static bool setEnabled(JSContext* cx, unsigned argc, Value* vp);
static bool getOnDebuggerStatement(JSContext* cx, unsigned argc, Value* vp);
static bool setOnDebuggerStatement(JSContext* cx, unsigned argc, Value* vp);
static bool getOnExceptionUnwind(JSContext* cx, unsigned argc, Value* vp);
static bool setOnExceptionUnwind(JSContext* cx, unsigned argc, Value* vp);
static bool getOnNewScript(JSContext* cx, unsigned argc, Value* vp);
static bool setOnNewScript(JSContext* cx, unsigned argc, Value* vp);
static bool getOnEnterFrame(JSContext* cx, unsigned argc, Value* vp);
static bool setOnEnterFrame(JSContext* cx, unsigned argc, Value* vp);
static bool getOnNewGlobalObject(JSContext* cx, unsigned argc, Value* vp);
static bool setOnNewGlobalObject(JSContext* cx, unsigned argc, Value* vp);
static bool getOnNewPromise(JSContext* cx, unsigned argc, Value* vp);
static bool setOnNewPromise(JSContext* cx, unsigned argc, Value* vp);
static bool getOnPromiseSettled(JSContext* cx, unsigned argc, Value* vp);
static bool setOnPromiseSettled(JSContext* cx, unsigned argc, Value* vp);
static bool getUncaughtExceptionHook(JSContext* cx, unsigned argc, Value* vp);
static bool setUncaughtExceptionHook(JSContext* cx, unsigned argc, Value* vp);
static bool getAllowUnobservedAsmJS(JSContext* cx, unsigned argc, Value* vp);
static bool setAllowUnobservedAsmJS(JSContext* cx, unsigned argc, Value* vp);
static bool getCollectCoverageInfo(JSContext* cx, unsigned argc, Value* vp);
static bool setCollectCoverageInfo(JSContext* cx, unsigned argc, Value* vp);
static bool getMemory(JSContext* cx, unsigned argc, Value* vp);
static bool addDebuggee(JSContext* cx, unsigned argc, Value* vp);
static bool addAllGlobalsAsDebuggees(JSContext* cx, unsigned argc, Value* vp);
static bool removeDebuggee(JSContext* cx, unsigned argc, Value* vp);
static bool removeAllDebuggees(JSContext* cx, unsigned argc, Value* vp);
static bool hasDebuggee(JSContext* cx, unsigned argc, Value* vp);
static bool getDebuggees(JSContext* cx, unsigned argc, Value* vp);
static bool getNewestFrame(JSContext* cx, unsigned argc, Value* vp);
static bool clearAllBreakpoints(JSContext* cx, unsigned argc, Value* vp);
static bool findScripts(JSContext* cx, unsigned argc, Value* vp);
static bool findSources(JSContext* cx, unsigned argc, Value* vp);
static bool findObjects(JSContext* cx, unsigned argc, Value* vp);
static bool findAllGlobals(JSContext* cx, unsigned argc, Value* vp);
static bool makeGlobalObjectReference(JSContext* cx, unsigned argc,
Value* vp);
static bool setupTraceLoggerScriptCalls(JSContext* cx, unsigned argc,
Value* vp);
static bool drainTraceLoggerScriptCalls(JSContext* cx, unsigned argc,
Value* vp);
static bool startTraceLogger(JSContext* cx, unsigned argc, Value* vp);
static bool endTraceLogger(JSContext* cx, unsigned argc, Value* vp);
static bool isCompilableUnit(JSContext* cx, unsigned argc, Value* vp);
static bool recordReplayProcessKind(JSContext* cx, unsigned argc, Value* vp);
#ifdef NIGHTLY_BUILD
static bool setupTraceLogger(JSContext* cx, unsigned argc, Value* vp);
static bool drainTraceLogger(JSContext* cx, unsigned argc, Value* vp);
#endif
static bool adoptDebuggeeValue(JSContext* cx, unsigned argc, Value* vp);
static bool adoptSource(JSContext* cx, unsigned argc, Value* vp);
static bool construct(JSContext* cx, unsigned argc, Value* vp);
static const JSPropertySpec properties[];
static const JSFunctionSpec methods[];
static const JSFunctionSpec static_methods[];
static void removeFromFrameMapsAndClearBreakpointsIn(JSContext* cx,
AbstractFramePtr frame,
bool suspending = false);
static bool updateExecutionObservabilityOfFrames(
JSContext* cx, const ExecutionObservableSet& obs, IsObserving observing);
static bool updateExecutionObservabilityOfScripts(
JSContext* cx, const ExecutionObservableSet& obs, IsObserving observing);
static bool updateExecutionObservability(JSContext* cx,
ExecutionObservableSet& obs,
IsObserving observing);
template <typename FrameFn /* void (DebuggerFrame*) */>
static void forEachDebuggerFrame(AbstractFramePtr frame, FrameFn fn);
/*
* Return a vector containing all Debugger.Frame instances referring to
* |frame|. |global| is |frame|'s global object; if nullptr or omitted, we
* compute it ourselves from |frame|.
*/
using DebuggerFrameVector = GCVector<DebuggerFrame*>;
static MOZ_MUST_USE bool getDebuggerFrames(
AbstractFramePtr frame, MutableHandle<DebuggerFrameVector> frames);
public:
static MOZ_MUST_USE bool ensureExecutionObservabilityOfOsrFrame(
JSContext* cx, InterpreterFrame* frame);
// Public for DebuggerScript_setBreakpoint.
static MOZ_MUST_USE bool ensureExecutionObservabilityOfScript(
JSContext* cx, JSScript* script);
// Whether the Debugger instance needs to observe all non-AOT JS
// execution of its debugees.
IsObserving observesAllExecution() const;
// Whether the Debugger instance needs to observe AOT-compiled asm.js
// execution of its debuggees.
IsObserving observesAsmJS() const;
// Whether the Debugger instance needs to observe coverage of any JavaScript
// execution.
IsObserving observesCoverage() const;
private:
static MOZ_MUST_USE bool ensureExecutionObservabilityOfFrame(
JSContext* cx, AbstractFramePtr frame);
static MOZ_MUST_USE bool ensureExecutionObservabilityOfRealm(
JSContext* cx, JS::Realm* realm);
static bool hookObservesAllExecution(Hook which);
MOZ_MUST_USE bool updateObservesAllExecutionOnDebuggees(
JSContext* cx, IsObserving observing);
MOZ_MUST_USE bool updateObservesCoverageOnDebuggees(JSContext* cx,
IsObserving observing);
void updateObservesAsmJSOnDebuggees(IsObserving observing);
JSObject* getHook(Hook hook) const;
bool hasAnyLiveHooks(JSRuntime* rt) const;
static MOZ_MUST_USE bool slowPathCheckNoExecute(JSContext* cx,
HandleScript script);
static ResumeMode slowPathOnEnterFrame(JSContext* cx, AbstractFramePtr frame);
static ResumeMode slowPathOnResumeFrame(JSContext* cx,
AbstractFramePtr frame);
static MOZ_MUST_USE bool slowPathOnLeaveFrame(JSContext* cx,
AbstractFramePtr frame,
jsbytecode* pc, bool ok);
static MOZ_MUST_USE bool slowPathOnNewGenerator(
JSContext* cx, AbstractFramePtr frame,
Handle<AbstractGeneratorObject*> genObj);
static ResumeMode slowPathOnDebuggerStatement(JSContext* cx,
AbstractFramePtr frame);
static ResumeMode slowPathOnExceptionUnwind(JSContext* cx,
AbstractFramePtr frame);
static void slowPathOnNewScript(JSContext* cx, HandleScript script);
static void slowPathOnNewWasmInstance(
JSContext* cx, Handle<WasmInstanceObject*> wasmInstance);
static void slowPathOnNewGlobalObject(JSContext* cx,
Handle<GlobalObject*> global);
static MOZ_MUST_USE bool slowPathOnLogAllocationSite(
JSContext* cx, HandleObject obj, HandleSavedFrame frame,
mozilla::TimeStamp when, GlobalObject::DebuggerVector& dbgs);
static void slowPathPromiseHook(JSContext* cx, Hook hook,
Handle<PromiseObject*> promise);
template <typename HookIsEnabledFun /* bool (Debugger*) */,
typename FireHookFun /* ResumeMode (Debugger*) */>
static ResumeMode dispatchHook(JSContext* cx, HookIsEnabledFun hookIsEnabled,
FireHookFun fireHook);
ResumeMode fireDebuggerStatement(JSContext* cx, MutableHandleValue vp);
ResumeMode fireExceptionUnwind(JSContext* cx, MutableHandleValue vp);
ResumeMode fireEnterFrame(JSContext* cx, MutableHandleValue vp);
ResumeMode fireNewGlobalObject(JSContext* cx, Handle<GlobalObject*> global,
MutableHandleValue vp);
ResumeMode firePromiseHook(JSContext* cx, Hook hook, HandleObject promise,
MutableHandleValue vp);
NativeObject* newVariantWrapper(JSContext* cx,
Handle<DebuggerScriptReferent> referent) {
return newDebuggerScript(cx, referent);
}
NativeObject* newVariantWrapper(JSContext* cx,
Handle<DebuggerSourceReferent> referent) {
return newDebuggerSource(cx, referent);
}
/*
* Helper function to help wrap Debugger objects whose referents may be
* variants. Currently Debugger.Script and Debugger.Source referents may
* be variants.
*
* Prefer using wrapScript, wrapWasmScript, wrapSource, and wrapWasmSource
* whenever possible.
*/
template <typename ReferentVariant, typename Referent, typename Map>
JSObject* wrapVariantReferent(JSContext* cx, Map& map,
Handle<CrossCompartmentKey> key,
Handle<ReferentVariant> referent);
JSObject* wrapVariantReferent(JSContext* cx,
Handle<DebuggerScriptReferent> referent);
JSObject* wrapVariantReferent(JSContext* cx,
Handle<DebuggerSourceReferent> referent);
/*
* Allocate and initialize a Debugger.Script instance whose referent is
* |referent|.
*/
NativeObject* newDebuggerScript(JSContext* cx,
Handle<DebuggerScriptReferent> referent);
/*
* Allocate and initialize a Debugger.Source instance whose referent is
* |referent|.
*/
NativeObject* newDebuggerSource(JSContext* cx,
Handle<DebuggerSourceReferent> referent);
/*
* Receive a "new script" event from the engine. A new script was compiled
* or deserialized.
*/
void fireNewScript(JSContext* cx,
Handle<DebuggerScriptReferent> scriptReferent);
/*
* Receive a "garbage collection" event from the engine. A GC cycle with the
* given data was recently completed.
*/
void fireOnGarbageCollectionHook(
JSContext* cx, const JS::dbg::GarbageCollectionEvent::Ptr& gcData);
inline Breakpoint* firstBreakpoint() const;
static MOZ_MUST_USE bool replaceFrameGuts(JSContext* cx,
AbstractFramePtr from,
AbstractFramePtr to,
ScriptFrameIter& iter);
public:
Debugger(JSContext* cx, NativeObject* dbg);
~Debugger();
inline const js::GCPtrNativeObject& toJSObject() const;
inline js::GCPtrNativeObject& toJSObjectRef();
static inline Debugger* fromJSObject(const JSObject* obj);
static Debugger* fromChildJSObject(JSObject* obj);
Zone* zone() const { return toJSObject()->zone(); }
bool hasMemory() const;
DebuggerMemory& memory() const;
WeakGlobalObjectSet::Range allDebuggees() const { return debuggees.all(); }
/*** Methods for interaction with the GC. *******************************/
/*
* A Debugger object is live if:
* * the Debugger JSObject is live (Debugger::trace handles this case); OR
* * it is in the middle of dispatching an event (the event dispatching
* code roots it in this case); OR
* * it is enabled, and it is debugging at least one live compartment,
* and at least one of the following is true:
* - it has a debugger hook installed
* - it has a breakpoint set on a live script
* - it has a watchpoint set on a live object.
*
* Debugger::markIteratively handles the last case. If it finds any Debugger
* objects that are definitely live but not yet marked, it marks them and
* returns true. If not, it returns false.
*/
static void traceIncomingCrossCompartmentEdges(JSTracer* tracer);
static MOZ_MUST_USE bool markIteratively(GCMarker* marker);
static void traceAllForMovingGC(JSTracer* trc);
static void sweepAll(FreeOp* fop);
static void detachAllDebuggersFromGlobal(FreeOp* fop, GlobalObject* global);
static MOZ_MUST_USE bool findSweepGroupEdges(JS::Zone* zone);
#ifdef DEBUG
static bool isDebuggerCrossCompartmentEdge(JSObject* obj,
const js::gc::Cell* cell);
#endif
// Checks it the current compartment is allowed to execute code.