Hi, I have found a regression in gcc and have bisected it to a particular commit.
Having read the bug reporting page there's nothing that really covers my situation.
I can can tell you that commit xxx breaks some gecko source code giving an internal compiler error and a line number in an include file.
If I generate pre-processed source using g++ -E. I can successfully compile this into an object file without the error showing itself.
The error though is reproducible when compiling in the normal manner in the source tree and can be invoked by the compilation of a single file.
When building the source tree the error can occur in a more random manner in that it does not occur on the same source file every time but the source file that fails always contains the same #include and reports the same error and line number every time.
The faulty commit is 067e9a502dcaabcecda20a00b3f7c6160d8eea93
The error message is.
Development/bluegriffon/BUILD/gecko-dev-042b84a/opt/dist/include/jsfriendapi.h:2005:1: internal compiler error: in write_type, at cp/mangle.c:2073
2005 | JS_GetArrayBufferData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
The file is attached but I am unable to attach the pre-processed source as it exceeds the 400k mail size allowance.
Before filing a bug it would be helpful to know if I have provided sufficient information or whether there is more that I should do to aid those may fix the problem.
Colin Close
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sts=4 et sw=4 tw=99:
* 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 jsfriendapi_h
#define jsfriendapi_h
#include "mozilla/Atomics.h"
#include "mozilla/Casting.h"
#include "mozilla/Maybe.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/UniquePtr.h"
#include "jsapi.h" // For JSAutoByteString. See bug 1033916.
#include "jsbytecode.h"
#include "jspubtd.h"
#include "js/CallArgs.h"
#include "js/CallNonGenericMethod.h"
#include "js/Class.h"
#include "js/Utility.h"
#if JS_STACK_GROWTH_DIRECTION > 0
# define JS_CHECK_STACK_SIZE(limit, sp) (MOZ_LIKELY((uintptr_t)(sp) < (limit)))
#else
# define JS_CHECK_STACK_SIZE(limit, sp) (MOZ_LIKELY((uintptr_t)(sp) > (limit)))
#endif
class JSAtom;
struct JSErrorFormatString;
class JSLinearString;
struct JSJitInfo;
class JSErrorReport;
namespace JS {
template <class T>
class Heap;
} /* namespace JS */
namespace js {
class JS_FRIEND_API(BaseProxyHandler);
class InterpreterFrame;
} /* namespace js */
extern JS_FRIEND_API(void)
JS_SetGrayGCRootsTracer(JSContext* cx, JSTraceDataOp traceOp, void* data);
extern JS_FRIEND_API(JSObject*)
JS_FindCompilationScope(JSContext* cx, JS::HandleObject obj);
extern JS_FRIEND_API(JSFunction*)
JS_GetObjectFunction(JSObject* obj);
extern JS_FRIEND_API(bool)
JS_SplicePrototype(JSContext* cx, JS::HandleObject obj, JS::HandleObject proto);
extern JS_FRIEND_API(JSObject*)
JS_NewObjectWithUniqueType(JSContext* cx, const JSClass* clasp, JS::HandleObject proto);
/**
* Allocate an object in exactly the same way as JS_NewObjectWithGivenProto, but
* without invoking the metadata callback on it. This allows creation of
* internal bookkeeping objects that are guaranteed to not have metadata
* attached to them.
*/
extern JS_FRIEND_API(JSObject*)
JS_NewObjectWithoutMetadata(JSContext* cx, const JSClass* clasp, JS::Handle<JSObject*> proto);
extern JS_FRIEND_API(uint32_t)
JS_ObjectCountDynamicSlots(JS::HandleObject obj);
extern JS_FRIEND_API(size_t)
JS_SetProtoCalled(JSContext* cx);
extern JS_FRIEND_API(size_t)
JS_GetCustomIteratorCount(JSContext* cx);
extern JS_FRIEND_API(bool)
JS_NondeterministicGetWeakMapKeys(JSContext* cx, JS::HandleObject obj, JS::MutableHandleObject ret);
extern JS_FRIEND_API(bool)
JS_NondeterministicGetWeakSetKeys(JSContext* cx, JS::HandleObject obj, JS::MutableHandleObject ret);
// Raw JSScript* because this needs to be callable from a signal handler.
extern JS_FRIEND_API(unsigned)
JS_PCToLineNumber(JSScript* script, jsbytecode* pc, unsigned* columnp = nullptr);
/**
* Determine whether the given object is backed by a DeadObjectProxy.
*
* Such objects hold no other objects (they have no outgoing reference edges)
* and will throw if you touch them (e.g. by reading/writing a property).
*/
extern JS_FRIEND_API(bool)
JS_IsDeadWrapper(JSObject* obj);
/*
* Used by the cycle collector to trace through a shape or object group and
* all cycle-participating data it reaches, using bounded stack space.
*/
extern JS_FRIEND_API(void)
JS_TraceShapeCycleCollectorChildren(JS::CallbackTracer* trc, JS::GCCellPtr shape);
extern JS_FRIEND_API(void)
JS_TraceObjectGroupCycleCollectorChildren(JS::CallbackTracer* trc, JS::GCCellPtr group);
enum {
JS_TELEMETRY_GC_REASON,
JS_TELEMETRY_GC_IS_ZONE_GC,
JS_TELEMETRY_GC_MS,
JS_TELEMETRY_GC_BUDGET_MS,
JS_TELEMETRY_GC_ANIMATION_MS,
JS_TELEMETRY_GC_MAX_PAUSE_MS,
JS_TELEMETRY_GC_MARK_MS,
JS_TELEMETRY_GC_SWEEP_MS,
JS_TELEMETRY_GC_COMPACT_MS,
JS_TELEMETRY_GC_MARK_ROOTS_MS,
JS_TELEMETRY_GC_MARK_GRAY_MS,
JS_TELEMETRY_GC_SLICE_MS,
JS_TELEMETRY_GC_SLOW_PHASE,
JS_TELEMETRY_GC_MMU_50,
JS_TELEMETRY_GC_RESET,
JS_TELEMETRY_GC_RESET_REASON,
JS_TELEMETRY_GC_INCREMENTAL_DISABLED,
JS_TELEMETRY_GC_NON_INCREMENTAL,
JS_TELEMETRY_GC_NON_INCREMENTAL_REASON,
JS_TELEMETRY_GC_SCC_SWEEP_TOTAL_MS,
JS_TELEMETRY_GC_SCC_SWEEP_MAX_PAUSE_MS,
JS_TELEMETRY_GC_MINOR_REASON,
JS_TELEMETRY_GC_MINOR_REASON_LONG,
JS_TELEMETRY_GC_MINOR_US,
JS_TELEMETRY_GC_NURSERY_BYTES,
JS_TELEMETRY_GC_PRETENURE_COUNT,
JS_TELEMETRY_DEPRECATED_LANGUAGE_EXTENSIONS_IN_CONTENT,
JS_TELEMETRY_DEPRECATED_LANGUAGE_EXTENSIONS_IN_ADDONS,
JS_TELEMETRY_ADDON_EXCEPTIONS,
JS_TELEMETRY_AOT_USAGE,
JS_TELEMETRY_PRIVILEGED_PARSER_COMPILE_LAZY_AFTER_MS,
JS_TELEMETRY_WEB_PARSER_COMPILE_LAZY_AFTER_MS,
JS_TELEMETRY_END
};
typedef void
(*JSAccumulateTelemetryDataCallback)(int id, uint32_t sample, const char* key);
extern JS_FRIEND_API(void)
JS_SetAccumulateTelemetryCallback(JSContext* cx, JSAccumulateTelemetryDataCallback callback);
extern JS_FRIEND_API(bool)
JS_GetIsSecureContext(JSCompartment* compartment);
extern JS_FRIEND_API(JSPrincipals*)
JS_GetCompartmentPrincipals(JSCompartment* compartment);
extern JS_FRIEND_API(void)
JS_SetCompartmentPrincipals(JSCompartment* compartment, JSPrincipals* principals);
extern JS_FRIEND_API(JSPrincipals*)
JS_GetScriptPrincipals(JSScript* script);
extern JS_FRIEND_API(bool)
JS_ScriptHasMutedErrors(JSScript* script);
extern JS_FRIEND_API(JSObject*)
JS_CloneObject(JSContext* cx, JS::HandleObject obj, JS::HandleObject proto);
/**
* Copy the own properties of src to dst in a fast way. src and dst must both
* be native and must be in the compartment of cx. They must have the same
* class, the same parent, and the same prototype. Class reserved slots will
* NOT be copied.
*
* dst must not have any properties on it before this function is called.
*
* src must have been allocated via JS_NewObjectWithoutMetadata so that we can
* be sure it has no metadata that needs copying to dst. This also means that
* dst needs to have the compartment global as its parent. This function will
* preserve the existing metadata on dst, if any.
*/
extern JS_FRIEND_API(bool)
JS_InitializePropertiesFromCompatibleNativeObject(JSContext* cx,
JS::HandleObject dst,
JS::HandleObject src);
extern JS_FRIEND_API(JSString*)
JS_BasicObjectToString(JSContext* cx, JS::HandleObject obj);
namespace js {
JS_FRIEND_API(bool)
GetBuiltinClass(JSContext* cx, JS::HandleObject obj, ESClass* cls);
JS_FRIEND_API(const char*)
ObjectClassName(JSContext* cx, JS::HandleObject obj);
JS_FRIEND_API(void)
ReportOverRecursed(JSContext* maybecx);
JS_FRIEND_API(bool)
AddRawValueRoot(JSContext* cx, JS::Value* vp, const char* name);
JS_FRIEND_API(void)
RemoveRawValueRoot(JSContext* cx, JS::Value* vp);
JS_FRIEND_API(JSAtom*)
GetPropertyNameFromPC(JSScript* script, jsbytecode* pc);
#ifdef JS_DEBUG
/*
* Routines to print out values during debugging. These are FRIEND_API to help
* the debugger find them and to support temporarily hacking js::Dump* calls
* into other code. Note that there are overloads that do not require the FILE*
* parameter, which will default to stderr.
*/
extern JS_FRIEND_API(void)
DumpString(JSString* str, FILE* fp);
extern JS_FRIEND_API(void)
DumpAtom(JSAtom* atom, FILE* fp);
extern JS_FRIEND_API(void)
DumpObject(JSObject* obj, FILE* fp);
extern JS_FRIEND_API(void)
DumpChars(const char16_t* s, size_t n, FILE* fp);
extern JS_FRIEND_API(void)
DumpValue(const JS::Value& val, FILE* fp);
extern JS_FRIEND_API(void)
DumpId(jsid id, FILE* fp);
extern JS_FRIEND_API(void)
DumpInterpreterFrame(JSContext* cx, FILE* fp, InterpreterFrame* start = nullptr);
extern JS_FRIEND_API(bool)
DumpPC(JSContext* cx, FILE* fp);
extern JS_FRIEND_API(bool)
DumpScript(JSContext* cx, JSScript* scriptArg, FILE* fp);
// Versions for use directly in a debugger (default parameters are not handled
// well in gdb; built-in handles like stderr are not handled well in lldb.)
extern JS_FRIEND_API(void) DumpString(JSString* str);
extern JS_FRIEND_API(void) DumpAtom(JSAtom* atom);
extern JS_FRIEND_API(void) DumpObject(JSObject* obj);
extern JS_FRIEND_API(void) DumpChars(const char16_t* s, size_t n);
extern JS_FRIEND_API(void) DumpValue(const JS::Value& val);
extern JS_FRIEND_API(void) DumpId(jsid id);
extern JS_FRIEND_API(void) DumpInterpreterFrame(JSContext* cx, InterpreterFrame* start = nullptr);
extern JS_FRIEND_API(bool) DumpPC(JSContext* cx);
extern JS_FRIEND_API(bool) DumpScript(JSContext* cx, JSScript* scriptArg);
#endif
extern JS_FRIEND_API(void)
DumpBacktrace(JSContext* cx, FILE* fp);
extern JS_FRIEND_API(void)
DumpBacktrace(JSContext* cx);
} // namespace js
namespace JS {
/** Exposed for DumpJSStack */
extern JS_FRIEND_API(JS::UniqueChars)
FormatStackDump(JSContext* cx, JS::UniqueChars&& buf, bool showArgs, bool showLocals,
bool showThisProps);
/**
* Set all of the uninitialized lexicals on an object to undefined. Return
* true if any lexicals were initialized and false otherwise.
* */
extern JS_FRIEND_API(bool)
ForceLexicalInitialization(JSContext *cx, HandleObject obj);
/**
* Whether we are poisoning unused/released data for error detection. Governed
* by the JS_GC_POISONING #ifdef as well as the $JSGC_DISABLE_POISONING
* environment variable.
*/
extern JS_FRIEND_API(int)
IsGCPoisoning();
} // namespace JS
/**
* Copies all own properties from |obj| to |target|. |obj| must be a "native"
* object (that is to say, normal-ish - not an Array or a Proxy).
*
* This function immediately enters a compartment, and does not impose any
* restrictions on the compartment of |cx|.
*/
extern JS_FRIEND_API(bool)
JS_CopyPropertiesFrom(JSContext* cx, JS::HandleObject target, JS::HandleObject obj);
/*
* Single-property version of the above. This function asserts that an |own|
* property of the given name exists on |obj|.
*
* On entry, |cx| must be same-compartment with |obj|.
*
* The copyBehavior argument controls what happens with
* non-configurable properties.
*/
typedef enum {
MakeNonConfigurableIntoConfigurable,
CopyNonConfigurableAsIs
} PropertyCopyBehavior;
extern JS_FRIEND_API(bool)
JS_CopyPropertyFrom(JSContext* cx, JS::HandleId id, JS::HandleObject target,
JS::HandleObject obj,
PropertyCopyBehavior copyBehavior = CopyNonConfigurableAsIs);
extern JS_FRIEND_API(bool)
JS_WrapPropertyDescriptor(JSContext* cx, JS::MutableHandle<JS::PropertyDescriptor> desc);
struct JSFunctionSpecWithHelp {
const char* name;
JSNative call;
uint16_t nargs;
uint16_t flags;
const JSJitInfo* jitInfo;
const char* usage;
const char* help;
};
#define JS_FN_HELP(name,call,nargs,flags,usage,help) \
{name, call, nargs, (flags) | JSPROP_ENUMERATE | JSFUN_STUB_GSOPS, nullptr, usage, help}
#define JS_INLINABLE_FN_HELP(name,call,nargs,flags,native,usage,help) \
{name, call, nargs, (flags) | JSPROP_ENUMERATE | JSFUN_STUB_GSOPS, &js::jit::JitInfo_##native,\
usage, help}
#define JS_FS_HELP_END \
{nullptr, nullptr, 0, 0, nullptr, nullptr}
extern JS_FRIEND_API(bool)
JS_DefineFunctionsWithHelp(JSContext* cx, JS::HandleObject obj, const JSFunctionSpecWithHelp* fs);
namespace js {
extern JS_FRIEND_DATA(const js::ClassOps) ProxyClassOps;
extern JS_FRIEND_DATA(const js::ClassExtension) ProxyClassExtension;
extern JS_FRIEND_DATA(const js::ObjectOps) ProxyObjectOps;
/*
* Helper Macros for creating JSClasses that function as proxies.
*
* NB: The macro invocation must be surrounded by braces, so as to
* allow for potential JSClass extensions.
*/
#define PROXY_MAKE_EXT(objectMoved) \
{ \
js::proxy_WeakmapKeyDelegate, \
objectMoved \
}
#define PROXY_CLASS_WITH_EXT(name, flags, extPtr) \
{ \
name, \
js::Class::NON_NATIVE | \
JSCLASS_IS_PROXY | \
JSCLASS_DELAY_METADATA_BUILDER | \
flags, \
&js::ProxyClassOps, \
JS_NULL_CLASS_SPEC, \
extPtr, \
&js::ProxyObjectOps \
}
#define PROXY_CLASS_DEF(name, flags) \
PROXY_CLASS_WITH_EXT(name, flags, &js::ProxyClassExtension)
extern JS_FRIEND_API(JSObject*)
proxy_WeakmapKeyDelegate(JSObject* obj);
/**
* A class of objects that return source code on demand.
*
* When code is compiled with setSourceIsLazy(true), SpiderMonkey doesn't
* retain the source code (and doesn't do lazy bytecode generation). If we ever
* need the source code, say, in response to a call to Function.prototype.
* toSource or Debugger.Source.prototype.text, then we call the 'load' member
* function of the instance of this class that has hopefully been registered
* with the runtime, passing the code's URL, and hope that it will be able to
* find the source.
*/
class SourceHook {
public:
virtual ~SourceHook() { }
/**
* Set |*src| and |*length| to refer to the source code for |filename|.
* On success, the caller owns the buffer to which |*src| points, and
* should use JS_free to free it.
*/
virtual bool load(JSContext* cx, const char* filename, char16_t** src, size_t* length) = 0;
};
/**
* Have |cx| use |hook| to retrieve lazily-retrieved source code. See the
* comments for SourceHook. The context takes ownership of the hook, and
* will delete it when the context itself is deleted, or when a new hook is
* set.
*/
extern JS_FRIEND_API(void)
SetSourceHook(JSContext* cx, mozilla::UniquePtr<SourceHook> hook);
/** Remove |cx|'s source hook, and return it. The caller now owns the hook. */
extern JS_FRIEND_API(mozilla::UniquePtr<SourceHook>)
ForgetSourceHook(JSContext* cx);
extern JS_FRIEND_API(JS::Zone*)
GetCompartmentZone(JSCompartment* comp);
typedef bool
(* PreserveWrapperCallback)(JSContext* cx, JSObject* obj);
typedef enum {
CollectNurseryBeforeDump,
IgnoreNurseryObjects
} DumpHeapNurseryBehaviour;
/**
* Dump the complete object graph of heap-allocated things.
* fp is the file for the dump output.
*/
extern JS_FRIEND_API(void)
DumpHeap(JSContext* cx, FILE* fp, DumpHeapNurseryBehaviour nurseryBehaviour);
#ifdef JS_OLD_GETTER_SETTER_METHODS
JS_FRIEND_API(bool) obj_defineGetter(JSContext* cx, unsigned argc, JS::Value* vp);
JS_FRIEND_API(bool) obj_defineSetter(JSContext* cx, unsigned argc, JS::Value* vp);
#endif
extern JS_FRIEND_API(bool)
IsSystemCompartment(JSCompartment* comp);
extern JS_FRIEND_API(bool)
IsSystemZone(JS::Zone* zone);
extern JS_FRIEND_API(bool)
IsAtomsCompartment(JSCompartment* comp);
extern JS_FRIEND_API(bool)
IsAtomsZone(JS::Zone* zone);
struct WeakMapTracer
{
JSContext* context;
explicit WeakMapTracer(JSContext* cx) : context(cx) {}
// Weak map tracer callback, called once for every binding of every
// weak map that was live at the time of the last garbage collection.
//
// m will be nullptr if the weak map is not contained in a JS Object.
//
// The callback should not GC (and will assert in a debug build if it does so.)
virtual void trace(JSObject* m, JS::GCCellPtr key, JS::GCCellPtr value) = 0;
};
extern JS_FRIEND_API(void)
TraceWeakMaps(WeakMapTracer* trc);
extern JS_FRIEND_API(bool)
AreGCGrayBitsValid(JSContext* cx);
extern JS_FRIEND_API(bool)
ZoneGlobalsAreAllGray(JS::Zone* zone);
extern JS_FRIEND_API(bool)
IsObjectZoneSweepingOrCompacting(JSObject* obj);
typedef void
(*GCThingCallback)(void* closure, JS::GCCellPtr thing);
extern JS_FRIEND_API(void)
VisitGrayWrapperTargets(JS::Zone* zone, GCThingCallback callback, void* closure);
extern JS_FRIEND_API(JSObject*)
GetWeakmapKeyDelegate(JSObject* key);
/**
* Invoke cellCallback on every gray JSObject in the given zone.
*/
extern JS_FRIEND_API(void)
IterateGrayObjects(JS::Zone* zone, GCThingCallback cellCallback, void* data);
/**
* Invoke cellCallback on every gray JSObject in the given zone while cycle
* collection is in progress.
*/
extern JS_FRIEND_API(void)
IterateGrayObjectsUnderCC(JS::Zone* zone, GCThingCallback cellCallback, void* data);
#ifdef DEBUG
// Trace the heap and check there are no black to gray edges. These are
// not allowed since the cycle collector could throw away the gray thing and
// leave a dangling pointer.
//
// This doesn't trace weak maps as these are handled separately.
extern JS_FRIEND_API(bool)
CheckGrayMarkingState(JSContext* cx);
#endif
#ifdef JS_HAS_CTYPES
extern JS_FRIEND_API(size_t)
SizeOfDataIfCDataObject(mozilla::MallocSizeOf mallocSizeOf, JSObject* obj);
#endif
extern JS_FRIEND_API(JSCompartment*)
GetAnyCompartmentInZone(JS::Zone* zone);
/*
* Shadow declarations of JS internal structures, for access by inline access
* functions below. Do not use these structures in any other way. When adding
* new fields for access by inline methods, make sure to add static asserts to
* the original header file to ensure that offsets are consistent.
*/
namespace shadow {
struct ObjectGroup {
const Class* clasp;
JSObject* proto;
JSCompartment* compartment;
};
struct BaseShape {
const js::Class* clasp_;
JSObject* parent;
};
class Shape {
public:
shadow::BaseShape* base;
jsid _1;
uint32_t slotInfo;
static const uint32_t FIXED_SLOTS_SHIFT = 27;
};
/**
* This layout is shared by all native objects. For non-native objects, the
* group may always be accessed safely, and other members may be as well,
* depending on the object's specific layout.
*/
struct Object {
shadow::ObjectGroup* group;
shadow::Shape* shape;
JS::Value* slots;
void* _1;
size_t numFixedSlots() const { return shape->slotInfo >> Shape::FIXED_SLOTS_SHIFT; }
JS::Value* fixedSlots() const {
return (JS::Value*)(uintptr_t(this) + sizeof(shadow::Object));
}
JS::Value& slotRef(size_t slot) const {
size_t nfixed = numFixedSlots();
if (slot < nfixed)
return fixedSlots()[slot];
return slots[slot - nfixed];
}
};
struct Function {
Object base;
uint16_t nargs;
uint16_t flags;
/* Used only for natives */
JSNative native;
const JSJitInfo* jitinfo;
void* _1;
};
struct String
{
static const uint32_t INLINE_CHARS_BIT = JS_BIT(2);
static const uint32_t LATIN1_CHARS_BIT = JS_BIT(6);
static const uint32_t ROPE_FLAGS = 0;
static const uint32_t EXTERNAL_FLAGS = JS_BIT(5);
static const uint32_t TYPE_FLAGS_MASK = JS_BIT(6) - 1;
uint32_t flags;
uint32_t length;
union {
const JS::Latin1Char* nonInlineCharsLatin1;
const char16_t* nonInlineCharsTwoByte;
JS::Latin1Char inlineStorageLatin1[1];
char16_t inlineStorageTwoByte[1];
};
const JSStringFinalizer* externalFinalizer;
};
} /* namespace shadow */
// This is equal to |&JSObject::class_|. Use it in places where you don't want
// to #include jsobj.h.
extern JS_FRIEND_DATA(const js::Class* const) ObjectClassPtr;
inline const js::Class*
GetObjectClass(const JSObject* obj)
{
return reinterpret_cast<const shadow::Object*>(obj)->group->clasp;
}
inline const JSClass*
GetObjectJSClass(JSObject* obj)
{
return js::Jsvalify(GetObjectClass(obj));
}
JS_FRIEND_API(const Class*)
ProtoKeyToClass(JSProtoKey key);
// Returns the key for the class inherited by a given standard class (that
// is to say, the prototype of this standard class's prototype).
//
// You must be sure that this corresponds to a standard class with a cached
// JSProtoKey before calling this function. In general |key| will match the
// cached proto key, except in cases where multiple JSProtoKeys share a
// JSClass.
inline JSProtoKey
InheritanceProtoKeyForStandardClass(JSProtoKey key)
{
// [Object] has nothing to inherit from.
if (key == JSProto_Object)
return JSProto_Null;
// If we're ClassSpec defined return the proto key from that
if (ProtoKeyToClass(key)->specDefined())
return ProtoKeyToClass(key)->specInheritanceProtoKey();
// Otherwise, we inherit [Object].
return JSProto_Object;
}
JS_FRIEND_API(bool)
IsFunctionObject(JSObject* obj);
static MOZ_ALWAYS_INLINE JSCompartment*
GetObjectCompartment(JSObject* obj)
{
return reinterpret_cast<shadow::Object*>(obj)->group->compartment;
}
JS_FRIEND_API(JSObject*)
GetGlobalForObjectCrossCompartment(JSObject* obj);
JS_FRIEND_API(JSObject*)
GetPrototypeNoProxy(JSObject* obj);
JS_FRIEND_API(void)
AssertSameCompartment(JSContext* cx, JSObject* obj);
JS_FRIEND_API(void)
AssertSameCompartment(JSContext* cx, JS::HandleValue v);
#ifdef JS_DEBUG
JS_FRIEND_API(void)
AssertSameCompartment(JSObject* objA, JSObject* objB);
#else
inline void AssertSameCompartment(JSObject* objA, JSObject* objB) {}
#endif
JS_FRIEND_API(void)
NotifyAnimationActivity(JSObject* obj);
/**
* Return the outermost enclosing function (script) of the scripted caller.
* This function returns nullptr in several cases:
* - no script is running on the context
* - the caller is in global or eval code
* In particular, this function will "stop" its outermost search at eval() and
* thus it will really return the outermost enclosing function *since the
* innermost eval*.
*/
JS_FRIEND_API(JSFunction*)
GetOutermostEnclosingFunctionOfScriptedCaller(JSContext* cx);
JS_FRIEND_API(JSFunction*)
DefineFunctionWithReserved(JSContext* cx, JSObject* obj, const char* name, JSNative call,
unsigned nargs, unsigned attrs);
JS_FRIEND_API(JSFunction*)
NewFunctionWithReserved(JSContext* cx, JSNative call, unsigned nargs, unsigned flags,
const char* name);
JS_FRIEND_API(JSFunction*)
NewFunctionByIdWithReserved(JSContext* cx, JSNative native, unsigned nargs, unsigned flags,
jsid id);
JS_FRIEND_API(const JS::Value&)
GetFunctionNativeReserved(JSObject* fun, size_t which);
JS_FRIEND_API(void)
SetFunctionNativeReserved(JSObject* fun, size_t which, const JS::Value& val);
JS_FRIEND_API(bool)
FunctionHasNativeReserved(JSObject* fun);
JS_FRIEND_API(bool)
GetObjectProto(JSContext* cx, JS::HandleObject obj, JS::MutableHandleObject proto);
extern JS_FRIEND_API(JSObject*)
GetStaticPrototype(JSObject* obj);
JS_FRIEND_API(bool)
GetOriginalEval(JSContext* cx, JS::HandleObject scope,
JS::MutableHandleObject eval);
inline void*
GetObjectPrivate(JSObject* obj)
{
MOZ_ASSERT(GetObjectClass(obj)->flags & JSCLASS_HAS_PRIVATE);
const shadow::Object* nobj = reinterpret_cast<const shadow::Object*>(obj);
void** addr = reinterpret_cast<void**>(&nobj->fixedSlots()[nobj->numFixedSlots()]);
return *addr;
}
inline const JS::Value&
GetReservedSlot(JSObject* obj, size_t slot)
{
MOZ_ASSERT(slot < JSCLASS_RESERVED_SLOTS(GetObjectClass(obj)));
return reinterpret_cast<const shadow::Object*>(obj)->slotRef(slot);
}
JS_FRIEND_API(void)
SetReservedOrProxyPrivateSlotWithBarrier(JSObject* obj, size_t slot, const JS::Value& value);
inline void
SetReservedSlot(JSObject* obj, size_t slot, const JS::Value& value)
{
MOZ_ASSERT(slot < JSCLASS_RESERVED_SLOTS(GetObjectClass(obj)));
shadow::Object* sobj = reinterpret_cast<shadow::Object*>(obj);
if (sobj->slotRef(slot).isGCThing() || value.isGCThing())
SetReservedOrProxyPrivateSlotWithBarrier(obj, slot, value);
else
sobj->slotRef(slot) = value;
}
JS_FRIEND_API(uint32_t)
GetObjectSlotSpan(JSObject* obj);
inline const JS::Value&
GetObjectSlot(JSObject* obj, size_t slot)
{
MOZ_ASSERT(slot < GetObjectSlotSpan(obj));
return reinterpret_cast<const shadow::Object*>(obj)->slotRef(slot);
}
MOZ_ALWAYS_INLINE size_t
GetAtomLength(JSAtom* atom)
{
return reinterpret_cast<shadow::String*>(atom)->length;
}
static const uint32_t MaxStringLength = (1 << 28) - 1;
MOZ_ALWAYS_INLINE size_t
GetStringLength(JSString* s)
{
return reinterpret_cast<shadow::String*>(s)->length;
}
MOZ_ALWAYS_INLINE size_t
GetFlatStringLength(JSFlatString* s)
{
return reinterpret_cast<shadow::String*>(s)->length;
}
MOZ_ALWAYS_INLINE size_t
GetLinearStringLength(JSLinearString* s)
{
return reinterpret_cast<shadow::String*>(s)->length;
}
MOZ_ALWAYS_INLINE bool
LinearStringHasLatin1Chars(JSLinearString* s)
{
return reinterpret_cast<shadow::String*>(s)->flags & shadow::String::LATIN1_CHARS_BIT;
}
MOZ_ALWAYS_INLINE bool
AtomHasLatin1Chars(JSAtom* atom)
{
return reinterpret_cast<shadow::String*>(atom)->flags & shadow::String::LATIN1_CHARS_BIT;
}
MOZ_ALWAYS_INLINE bool
StringHasLatin1Chars(JSString* s)
{
return reinterpret_cast<shadow::String*>(s)->flags & shadow::String::LATIN1_CHARS_BIT;
}
MOZ_ALWAYS_INLINE const JS::Latin1Char*
GetLatin1LinearStringChars(const JS::AutoCheckCannotGC& nogc, JSLinearString* linear)
{
MOZ_ASSERT(LinearStringHasLatin1Chars(linear));
using shadow::String;
String* s = reinterpret_cast<String*>(linear);
if (s->flags & String::INLINE_CHARS_BIT)
return s->inlineStorageLatin1;
return s->nonInlineCharsLatin1;
}
MOZ_ALWAYS_INLINE const char16_t*
GetTwoByteLinearStringChars(const JS::AutoCheckCannotGC& nogc, JSLinearString* linear)
{
MOZ_ASSERT(!LinearStringHasLatin1Chars(linear));
using shadow::String;
String* s = reinterpret_cast<String*>(linear);
if (s->flags & String::INLINE_CHARS_BIT)
return s->inlineStorageTwoByte;
return s->nonInlineCharsTwoByte;
}
MOZ_ALWAYS_INLINE JSLinearString*
AtomToLinearString(JSAtom* atom)
{
return reinterpret_cast<JSLinearString*>(atom);
}
MOZ_ALWAYS_INLINE JSFlatString*
AtomToFlatString(JSAtom* atom)
{
return reinterpret_cast<JSFlatString*>(atom);
}
MOZ_ALWAYS_INLINE JSLinearString*
FlatStringToLinearString(JSFlatString* s)
{
return reinterpret_cast<JSLinearString*>(s);
}
MOZ_ALWAYS_INLINE const JS::Latin1Char*
GetLatin1AtomChars(const JS::AutoCheckCannotGC& nogc, JSAtom* atom)
{
return GetLatin1LinearStringChars(nogc, AtomToLinearString(atom));
}
MOZ_ALWAYS_INLINE const char16_t*
GetTwoByteAtomChars(const JS::AutoCheckCannotGC& nogc, JSAtom* atom)
{
return GetTwoByteLinearStringChars(nogc, AtomToLinearString(atom));
}
MOZ_ALWAYS_INLINE bool
IsExternalString(JSString* str, const JSStringFinalizer** fin, const char16_t** chars)
{
using shadow::String;
String* s = reinterpret_cast<String*>(str);
if ((s->flags & String::TYPE_FLAGS_MASK) != String::EXTERNAL_FLAGS)
return false;
MOZ_ASSERT(JS_IsExternalString(str));
*fin = s->externalFinalizer;
*chars = s->nonInlineCharsTwoByte;
return true;
}
JS_FRIEND_API(JSLinearString*)
StringToLinearStringSlow(JSContext* cx, JSString* str);
MOZ_ALWAYS_INLINE JSLinearString*
StringToLinearString(JSContext* cx, JSString* str)
{
using shadow::String;
String* s = reinterpret_cast<String*>(str);
if (MOZ_UNLIKELY((s->flags & String::TYPE_FLAGS_MASK) == String::ROPE_FLAGS))
return StringToLinearStringSlow(cx, str);
return reinterpret_cast<JSLinearString*>(str);
}
template<typename CharType>
MOZ_ALWAYS_INLINE void
CopyLinearStringChars(CharType* dest, JSLinearString* s, size_t len, size_t start = 0);
MOZ_ALWAYS_INLINE void
CopyLinearStringChars(char16_t* dest, JSLinearString* s, size_t len, size_t start = 0)
{
MOZ_ASSERT(start + len <= GetLinearStringLength(s));
JS::AutoCheckCannotGC nogc;
if (LinearStringHasLatin1Chars(s)) {
const JS::Latin1Char* src = GetLatin1LinearStringChars(nogc, s);
for (size_t i = 0; i < len; i++)
dest[i] = src[start + i];
} else {
const char16_t* src = GetTwoByteLinearStringChars(nogc, s);
mozilla::PodCopy(dest, src + start, len);
}
}
MOZ_ALWAYS_INLINE void
CopyLinearStringChars(char* dest, JSLinearString* s, size_t len, size_t start = 0)
{
MOZ_ASSERT(start + len <= GetLinearStringLength(s));
JS::AutoCheckCannotGC nogc;
if (LinearStringHasLatin1Chars(s)) {
const JS::Latin1Char* src = GetLatin1LinearStringChars(nogc, s);
for (size_t i = 0; i < len; i++)
dest[i] = char(src[start + i]);
} else {
const char16_t* src = GetTwoByteLinearStringChars(nogc, s);
for (size_t i = 0; i < len; i++)
dest[i] = char(src[start + i]);
}
}
template<typename CharType>
inline bool
CopyStringChars(JSContext* cx, CharType* dest, JSString* s, size_t len, size_t start = 0)
{
JSLinearString* linear = StringToLinearString(cx, s);
if (!linear)
return false;
CopyLinearStringChars(dest, linear, len, start);
return true;
}
inline void
CopyFlatStringChars(char16_t* dest, JSFlatString* s, size_t len)
{
CopyLinearStringChars(dest, FlatStringToLinearString(s), len);
}
/**
* Add some or all property keys of obj to the id vector *props.
*
* The flags parameter controls which property keys are added. Pass a
* combination of the following bits:
*
* JSITER_OWNONLY - Don't also search the prototype chain; only consider
* obj's own properties.
*
* JSITER_HIDDEN - Include nonenumerable properties.
*
* JSITER_SYMBOLS - Include property keys that are symbols. The default
* behavior is to filter out symbols.
*
* JSITER_SYMBOLSONLY - Exclude non-symbol property keys.
*
* This is the closest C++ API we have to `Reflect.ownKeys(obj)`, or
* equivalently, the ES6 [[OwnPropertyKeys]] internal method. Pass
* `JSITER_OWNONLY | JSITER_HIDDEN | JSITER_SYMBOLS` as flags to get
* results that match the output of Reflect.ownKeys.
*/
JS_FRIEND_API(bool)
GetPropertyKeys(JSContext* cx, JS::HandleObject obj, unsigned flags, JS::AutoIdVector* props);
JS_FRIEND_API(bool)
AppendUnique(JSContext* cx, JS::AutoIdVector& base, JS::AutoIdVector& others);
JS_FRIEND_API(bool)
StringIsArrayIndex(JSLinearString* str, uint32_t* indexp);
JS_FRIEND_API(void)
SetPreserveWrapperCallback(JSContext* cx, PreserveWrapperCallback callback);
JS_FRIEND_API(bool)
IsObjectInContextCompartment(JSObject* obj, const JSContext* cx);
/*
* NB: keep these in sync with the copy in builtin/SelfHostingDefines.h.
* The first three are omitted because they shouldn't be used in new code.
*/
#define JSITER_ENUMERATE 0x1 /* for-in compatible hidden default iterator */
#define JSITER_FOREACH 0x2 /* get obj[key] for each property */
#define JSITER_KEYVALUE 0x4 /* obsolete destructuring for-in wants [key, value] */
#define JSITER_OWNONLY 0x8 /* iterate over obj's own properties only */
#define JSITER_HIDDEN 0x10 /* also enumerate non-enumerable properties */
#define JSITER_SYMBOLS 0x20 /* also include symbol property keys */
#define JSITER_SYMBOLSONLY 0x40 /* exclude string property keys */
#define JSITER_FORAWAITOF 0x80 /* for-await-of */
JS_FRIEND_API(bool)
RunningWithTrustedPrincipals(JSContext* cx);
MOZ_ALWAYS_INLINE uintptr_t
GetNativeStackLimit(JSContext* cx, JS::StackKind kind, int extraAllowance = 0)
{
uintptr_t limit = JS::RootingContext::get(cx)->nativeStackLimit[kind];
#if JS_STACK_GROWTH_DIRECTION > 0
limit += extraAllowance;
#else
limit -= extraAllowance;
#endif
return limit;
}
MOZ_ALWAYS_INLINE uintptr_t
GetNativeStackLimit(JSContext* cx, int extraAllowance = 0)
{
JS::StackKind kind = RunningWithTrustedPrincipals(cx) ? JS::StackForTrustedScript
: JS::StackForUntrustedScript;
return GetNativeStackLimit(cx, kind, extraAllowance);
}
/*
* These functions return |false| if we are close to using up the C++ stack.
* They also report an overrecursion error, except for the DontReport variants.
* The CheckSystemRecursionLimit variant gives us a little extra space so we
* can ensure that crucial code is able to run. CheckRecursionLimitConservative
* allows less space than any other check, including a safety buffer (as in, it
* uses the untrusted limit and subtracts a little more from it).
*/
MOZ_ALWAYS_INLINE bool
CheckRecursionLimit(JSContext* cx, uintptr_t limit)
{
int stackDummy;
if (!JS_CHECK_STACK_SIZE(limit, &stackDummy)) {
ReportOverRecursed(cx);
return false;
}
return true;
}
MOZ_ALWAYS_INLINE bool
CheckRecursionLimitDontReport(JSContext* cx, uintptr_t limit)
{
int stackDummy;
return JS_CHECK_STACK_SIZE(limit, &stackDummy);
}
MOZ_ALWAYS_INLINE bool
CheckRecursionLimit(JSContext* cx)
{
// GetNativeStackLimit(cx) is pretty slow because it has to do an uninlined
// call to RunningWithTrustedPrincipals to determine which stack limit to
// use. To work around this, check the untrusted limit first to avoid the
// overhead in most cases.
uintptr_t untrustedLimit = GetNativeStackLimit(cx, JS::StackForUntrustedScript);
if (MOZ_LIKELY(CheckRecursionLimitDontReport(cx, untrustedLimit)))
return true;
return CheckRecursionLimit(cx, GetNativeStackLimit(cx));
}
MOZ_ALWAYS_INLINE bool
CheckRecursionLimitDontReport(JSContext* cx)
{
return CheckRecursionLimitDontReport(cx, GetNativeStackLimit(cx));
}
MOZ_ALWAYS_INLINE bool
CheckRecursionLimitWithStackPointerDontReport(JSContext* cx, void* sp)
{
return JS_CHECK_STACK_SIZE(GetNativeStackLimit(cx), sp);
}
MOZ_ALWAYS_INLINE bool
CheckRecursionLimitWithStackPointer(JSContext* cx, void* sp)
{
if (!JS_CHECK_STACK_SIZE(GetNativeStackLimit(cx), sp)) {
ReportOverRecursed(cx);
return false;
}
return true;
}
MOZ_ALWAYS_INLINE bool
CheckSystemRecursionLimit(JSContext* cx)
{
return CheckRecursionLimit(cx, GetNativeStackLimit(cx, JS::StackForSystemCode));
}
MOZ_ALWAYS_INLINE bool
CheckRecursionLimitConservative(JSContext* cx)
{
return CheckRecursionLimit(cx, GetNativeStackLimit(cx, JS::StackForUntrustedScript,
-1024 * int(sizeof(size_t))));
}
MOZ_ALWAYS_INLINE bool
CheckRecursionLimitConservativeDontReport(JSContext* cx)
{
return CheckRecursionLimitDontReport(cx, GetNativeStackLimit(cx, JS::StackForUntrustedScript,
-1024 * int(sizeof(size_t))));
}
JS_FRIEND_API(void)
StartPCCountProfiling(JSContext* cx);
JS_FRIEND_API(void)
StopPCCountProfiling(JSContext* cx);
JS_FRIEND_API(void)
PurgePCCounts(JSContext* cx);
JS_FRIEND_API(size_t)
GetPCCountScriptCount(JSContext* cx);
JS_FRIEND_API(JSString*)
GetPCCountScriptSummary(JSContext* cx, size_t script);
JS_FRIEND_API(JSString*)
GetPCCountScriptContents(JSContext* cx, size_t script);
/**
* Generate lcov trace file content for the current compartment, and allocate a
* new buffer and return the content in it, the size of the newly allocated
* content within the buffer would be set to the length out-param.
*
* In case of out-of-memory, this function returns nullptr and does not set any
* value to the length out-param.
*/
JS_FRIEND_API(char*)
GetCodeCoverageSummary(JSContext* cx, size_t* length);
typedef void
(* ActivityCallback)(void* arg, bool active);
/**
* Sets a callback that is run whenever the runtime goes idle - the
* last active request ceases - and begins activity - when it was
* idle and a request begins.
*/
JS_FRIEND_API(void)
SetActivityCallback(JSContext* cx, ActivityCallback cb, void* arg);
typedef bool
(* DOMInstanceClassHasProtoAtDepth)(const Class* instanceClass,
uint32_t protoID, uint32_t depth);
struct JSDOMCallbacks {
DOMInstanceClassHasProtoAtDepth instanceClassMatchesProto;
};
typedef struct JSDOMCallbacks DOMCallbacks;
extern JS_FRIEND_API(void)
SetDOMCallbacks(JSContext* cx, const DOMCallbacks* callbacks);
extern JS_FRIEND_API(const DOMCallbacks*)
GetDOMCallbacks(JSContext* cx);
extern JS_FRIEND_API(JSObject*)
GetTestingFunctions(JSContext* cx);
/**
* Helper to convert FreeOp to JSFreeOp when the definition of FreeOp is not
* available and the compiler does not know that FreeOp inherits from
* JSFreeOp.
*/
inline JSFreeOp*
CastToJSFreeOp(FreeOp* fop)
{
return reinterpret_cast<JSFreeOp*>(fop);
}
/* Implemented in jsexn.cpp. */
/**
* Get an error type name from a JSExnType constant.
* Returns nullptr for invalid arguments and JSEXN_INTERNALERR
*/
extern JS_FRIEND_API(JSFlatString*)
GetErrorTypeName(JSContext* cx, int16_t exnType);
#ifdef JS_DEBUG
extern JS_FRIEND_API(unsigned)
GetEnterCompartmentDepth(JSContext* cx);
#endif
extern JS_FRIEND_API(bool)
RegExpToSharedNonInline(JSContext* cx, JS::HandleObject regexp,
JS::MutableHandle<RegExpShared*> shared);
/* Implemented in CrossCompartmentWrapper.cpp. */
typedef enum NukeReferencesToWindow {
NukeWindowReferences,
DontNukeWindowReferences
} NukeReferencesToWindow;
typedef enum NukeReferencesFromTarget {
NukeAllReferences,
NukeIncomingReferences,
} NukeReferencesFromTarget;
/*
* These filters are designed to be ephemeral stack classes, and thus don't
* do any rooting or holding of their members.
*/
struct CompartmentFilter {
virtual bool match(JSCompartment* c) const = 0;
};
struct AllCompartments : public CompartmentFilter {
virtual bool match(JSCompartment* c) const override { return true; }
};
struct ContentCompartmentsOnly : public CompartmentFilter {
virtual bool match(JSCompartment* c) const override {
return !IsSystemCompartment(c);
}
};
struct ChromeCompartmentsOnly : public CompartmentFilter {
virtual bool match(JSCompartment* c) const override {
return IsSystemCompartment(c);
}
};
struct SingleCompartment : public CompartmentFilter {
JSCompartment* ours;
explicit SingleCompartment(JSCompartment* c) : ours(c) {}
virtual bool match(JSCompartment* c) const override { return c == ours; }
};
struct CompartmentsWithPrincipals : public CompartmentFilter {
JSPrincipals* principals;
explicit CompartmentsWithPrincipals(JSPrincipals* p) : principals(p) {}
virtual bool match(JSCompartment* c) const override {
return JS_GetCompartmentPrincipals(c) == principals;
}
};
extern JS_FRIEND_API(bool)
NukeCrossCompartmentWrappers(JSContext* cx,
const CompartmentFilter& sourceFilter,
const CompartmentFilter& targetFilter,
NukeReferencesToWindow nukeReferencesToWindow,
NukeReferencesFromTarget nukeReferencesFromTarget);
/* Specify information about DOMProxy proxies in the DOM, for use by ICs. */
/*
* The DOMProxyShadowsCheck function will be called to check if the property for
* id should be gotten from the prototype, or if there is an own property that
* shadows it.
* * If ShadowsViaDirectExpando is returned, then the slot at
* listBaseExpandoSlot contains an expando object which has the property in
* question.
* * If ShadowsViaIndirectExpando is returned, then the slot at
* listBaseExpandoSlot contains a private pointer to an ExpandoAndGeneration
* and the expando object in the ExpandoAndGeneration has the property in
* question.
* * If DoesntShadow is returned then the slot at listBaseExpandoSlot should
* either be undefined or point to an expando object that would contain the
* own property.
* * If DoesntShadowUnique is returned then the slot at listBaseExpandoSlot
* should contain a private pointer to a ExpandoAndGeneration, which contains
* a JS::Value that should either be undefined or point to an expando object,
* and a uint64 value. If that value changes then the IC for getting a
* property will be invalidated.
* * If Shadows is returned, that means the property is an own property of the
* proxy but doesn't live on the expando object.
*/
struct ExpandoAndGeneration {
ExpandoAndGeneration()
: expando(JS::UndefinedValue()),
generation(0)
{}
void OwnerUnlinked()
{
++generation;
}
static size_t offsetOfExpando()
{
return offsetof(ExpandoAndGeneration, expando);
}
static size_t offsetOfGeneration()
{
return offsetof(ExpandoAndGeneration, generation);
}
JS::Heap<JS::Value> expando;
uint64_t generation;
};
typedef enum DOMProxyShadowsResult {
ShadowCheckFailed,
Shadows,
DoesntShadow,
DoesntShadowUnique,
ShadowsViaDirectExpando,
ShadowsViaIndirectExpando
} DOMProxyShadowsResult;
typedef DOMProxyShadowsResult
(* DOMProxyShadowsCheck)(JSContext* cx, JS::HandleObject object, JS::HandleId id);
JS_FRIEND_API(void)
SetDOMProxyInformation(const void* domProxyHandlerFamily, uint32_t domProxyExpandoSlot,
DOMProxyShadowsCheck domProxyShadowsCheck);
const void* GetDOMProxyHandlerFamily();
uint32_t GetDOMProxyExpandoSlot();
DOMProxyShadowsCheck GetDOMProxyShadowsCheck();
inline bool DOMProxyIsShadowing(DOMProxyShadowsResult result) {
return result == Shadows ||
result == ShadowsViaDirectExpando ||
result == ShadowsViaIndirectExpando;
}
/* Implemented in jsdate.cpp. */
/** Detect whether the internal date value is NaN. */
extern JS_FRIEND_API(bool)
DateIsValid(JSContext* cx, JS::HandleObject obj, bool* isValid);
extern JS_FRIEND_API(bool)
DateGetMsecSinceEpoch(JSContext* cx, JS::HandleObject obj, double* msecSinceEpoch);
} /* namespace js */
/* Implemented in jscntxt.cpp. */
/**
* Report an exception, which is currently realized as a printf-style format
* string and its arguments.
*/
typedef enum JSErrNum {
#define MSG_DEF(name, count, exception, format) \
name,
#include "js.msg"
#undef MSG_DEF
JSErr_Limit
} JSErrNum;
namespace js {
extern JS_FRIEND_API(const JSErrorFormatString*)
GetErrorMessage(void* userRef, const unsigned errorNumber);
// AutoStableStringChars is here so we can use it in ErrorReport. It
// should get moved out of here if we can manage it. See bug 1040316.
/**
* This class provides safe access to a string's chars across a GC. Once
* we allocate strings and chars in the nursery (bug 903519), this class
* will have to make a copy of the string's chars if they are allocated
* in the nursery, so it's best to avoid using this class unless you really
* need it. It's usually more efficient to use the latin1Chars/twoByteChars
* JSString methods and often the code can be rewritten so that only indexes
* instead of char pointers are used in parts of the code that can GC.
*/
class MOZ_STACK_CLASS JS_FRIEND_API(AutoStableStringChars)
{
/*
* When copying string char, use this many bytes of inline storage. This is
* chosen to allow the inline string types to be copied without allocating.
* This is asserted in AutoStableStringChars::allocOwnChars.
*/
static const size_t InlineCapacity = 24;
/* Ensure the string is kept alive while we're using its chars. */
JS::RootedString s_;
union {
const char16_t* twoByteChars_;
const JS::Latin1Char* latin1Chars_;
};
mozilla::Maybe<Vector<uint8_t, InlineCapacity>> ownChars_;
enum State { Uninitialized, Latin1, TwoByte };
State state_;
public:
explicit AutoStableStringChars(JSContext* cx)
: s_(cx), state_(Uninitialized)
{}
MOZ_MUST_USE
bool init(JSContext* cx, JSString* s);
/* Like init(), but Latin1 chars are inflated to TwoByte. */
MOZ_MUST_USE
bool initTwoByte(JSContext* cx, JSString* s);
bool isLatin1() const { return state_ == Latin1; }
bool isTwoByte() const { return state_ == TwoByte; }
const char16_t* twoByteChars() const {
MOZ_ASSERT(state_ == TwoByte);
return twoByteChars_;
}
mozilla::Range<const JS::Latin1Char> latin1Range() const {
MOZ_ASSERT(state_ == Latin1);
return mozilla::Range<const JS::Latin1Char>(latin1Chars_,
GetStringLength(s_));
}
mozilla::Range<const char16_t> twoByteRange() const {
MOZ_ASSERT(state_ == TwoByte);
return mozilla::Range<const char16_t>(twoByteChars_,
GetStringLength(s_));
}
/* If we own the chars, transfer ownership to the caller. */
bool maybeGiveOwnershipToCaller() {
MOZ_ASSERT(state_ != Uninitialized);
if (!ownChars_.isSome() || !ownChars_->extractRawBuffer())
return false;
state_ = Uninitialized;
ownChars_.reset();
return true;
}
private:
AutoStableStringChars(const AutoStableStringChars& other) = delete;
void operator=(const AutoStableStringChars& other) = delete;
bool baseIsInline(JS::Handle<JSLinearString*> linearString);
template <typename T> T* allocOwnChars(JSContext* cx, size_t count);
bool copyLatin1Chars(JSContext* cx, JS::Handle<JSLinearString*> linearString);
bool copyTwoByteChars(JSContext* cx, JS::Handle<JSLinearString*> linearString);
bool copyAndInflateLatin1Chars(JSContext*, JS::Handle<JSLinearString*> linearString);
};
struct MOZ_STACK_CLASS JS_FRIEND_API(ErrorReport)
{
explicit ErrorReport(JSContext* cx);
~ErrorReport();
enum SniffingBehavior {
WithSideEffects,
NoSideEffects
};
/**
* Generate a JSErrorReport from the provided thrown value.
*
* If the value is a (possibly wrapped) Error object, the JSErrorReport will
* be exactly initialized from the Error object's information, without
* observable side effects. (The Error object's JSErrorReport is reused, if
* it has one.)
*
* Otherwise various attempts are made to derive JSErrorReport information
* from |exn| and from the current execution state. This process is
* *definitely* inconsistent with any standard, and particulars of the
* behavior implemented here generally shouldn't be relied upon.
*
* If the value of |sniffingBehavior| is |WithSideEffects|, some of these
* attempts *may* invoke user-configurable behavior when |exn| is an object:
* converting |exn| to a string, detecting and getting properties on |exn|,
* accessing |exn|'s prototype chain, and others are possible. Users *must*
* tolerate |ErrorReport::init| potentially having arbitrary effects. Any
* exceptions thrown by these operations will be caught and silently
* ignored, and "default" values will be substituted into the JSErrorReport.
*
* But if the value of |sniffingBehavior| is |NoSideEffects|, these attempts
* *will not* invoke any observable side effects. The JSErrorReport will
* simply contain fewer, less precise details.
*
* Unlike some functions involved in error handling, this function adheres
* to the usual JSAPI return value error behavior.
*/
bool init(JSContext* cx, JS::HandleValue exn,
SniffingBehavior sniffingBehavior);
JSErrorReport* report()
{
return reportp;
}
const JS::ConstUTF8CharsZ toStringResult()
{
return toStringResult_;
}
private:
// More or less an equivalent of JS_ReportErrorNumber/js::ReportErrorNumberVA
// but fills in an ErrorReport instead of reporting it. Uses varargs to
// make it simpler to call js::ExpandErrorArgumentsVA.
//
// Returns false if we fail to actually populate the ErrorReport
// for some reason (probably out of memory).
bool populateUncaughtExceptionReportUTF8(JSContext* cx, ...);
bool populateUncaughtExceptionReportUTF8VA(JSContext* cx, va_list ap);
// Reports exceptions from add-on scopes to telementry.
void ReportAddonExceptionToTelementry(JSContext* cx);
// We may have a provided JSErrorReport, so need a way to represent that.
JSErrorReport* reportp;
// Or we may need to synthesize a JSErrorReport one of our own.
JSErrorReport ownedReport;
// And we have a string to maybe keep alive that has pointers into
// it from ownedReport.
JS::RootedString str;
// And keep its chars alive too.
AutoStableStringChars strChars;
// And we need to root our exception value.
JS::RootedObject exnObject;
// And for our filename.
JSAutoByteString filename;
// We may have a result of error.toString().
// FIXME: We should not call error.toString(), since it could have side
// effect (see bug 633623).
JS::ConstUTF8CharsZ toStringResult_;
JSAutoByteString toStringResultBytesStorage;
};
/* Implemented in vm/StructuredClone.cpp. */
extern JS_FRIEND_API(uint64_t)
GetSCOffset(JSStructuredCloneWriter* writer);
namespace Scalar {
/**
* Scalar types that can appear in typed arrays and typed objects. The enum
* values must to be kept in sync with the JS_SCALARTYPEREPR_ constants, as
* well as the TypedArrayObject::classes and TypedArrayObject::protoClasses
* definitions.
*/
enum Type {
Int8 = 0,
Uint8,
Int16,
Uint16,
Int32,
Uint32,
Float32,
Float64,
/**
* Special type that is a uint8_t, but assignments are clamped to [0, 256).
* Treat the raw data type as a uint8_t.
*/
Uint8Clamped,
/**
* Types that don't have their own TypedArray equivalent, for now.
*/
MaxTypedArrayViewType,
Int64,
Float32x4,
Int8x16,
Int16x8,
Int32x4
};
static inline size_t
byteSize(Type atype)
{
switch (atype) {
case Int8:
case Uint8:
case Uint8Clamped:
return 1;
case Int16:
case Uint16:
return 2;
case Int32:
case Uint32:
case Float32:
return 4;
case Int64:
case Float64:
return 8;
case Int8x16:
case Int16x8:
case Int32x4:
case Float32x4:
return 16;
default:
MOZ_CRASH("invalid scalar type");
}
}
static inline bool
isSignedIntType(Type atype) {
switch (atype) {
case Int8:
case Int16:
case Int32:
case Int64:
case Int8x16:
case Int16x8:
case Int32x4:
return true;
case Uint8:
case Uint8Clamped:
case Uint16:
case Uint32:
case Float32:
case Float64:
case Float32x4:
return false;
default:
MOZ_CRASH("invalid scalar type");
}
}
static inline bool
isSimdType(Type atype) {
switch (atype) {
case Int8:
case Uint8:
case Uint8Clamped:
case Int16:
case Uint16:
case Int32:
case Uint32:
case Int64:
case Float32:
case Float64:
return false;
case Int8x16:
case Int16x8:
case Int32x4:
case Float32x4:
return true;
case MaxTypedArrayViewType:
break;
}
MOZ_CRASH("invalid scalar type");
}
static inline size_t
scalarByteSize(Type atype) {
switch (atype) {
case Int8x16:
return 1;
case Int16x8:
return 2;
case Int32x4:
case Float32x4:
return 4;
case Int8:
case Uint8:
case Uint8Clamped:
case Int16:
case Uint16:
case Int32:
case Uint32:
case Int64:
case Float32:
case Float64:
case MaxTypedArrayViewType:
break;
}
MOZ_CRASH("invalid simd type");
}
} /* namespace Scalar */
} /* namespace js */
/*
* Create a new typed array with nelements elements.
*
* These functions (except the WithBuffer variants) fill in the array with zeros.
*/
extern JS_FRIEND_API(JSObject*)
JS_NewInt8Array(JSContext* cx, uint32_t nelements);
extern JS_FRIEND_API(JSObject*)
JS_NewUint8Array(JSContext* cx, uint32_t nelements);
extern JS_FRIEND_API(JSObject*)
JS_NewUint8ClampedArray(JSContext* cx, uint32_t nelements);
extern JS_FRIEND_API(JSObject*)
JS_NewInt16Array(JSContext* cx, uint32_t nelements);
extern JS_FRIEND_API(JSObject*)
JS_NewUint16Array(JSContext* cx, uint32_t nelements);
extern JS_FRIEND_API(JSObject*)
JS_NewInt32Array(JSContext* cx, uint32_t nelements);
extern JS_FRIEND_API(JSObject*)
JS_NewUint32Array(JSContext* cx, uint32_t nelements);
extern JS_FRIEND_API(JSObject*)
JS_NewFloat32Array(JSContext* cx, uint32_t nelements);
extern JS_FRIEND_API(JSObject*)
JS_NewFloat64Array(JSContext* cx, uint32_t nelements);
/*
* Create a new typed array and copy in values from the given object. The
* object is used as if it were an array; that is, the new array (if
* successfully created) will have length given by array.length, and its
* elements will be those specified by array[0], array[1], and so on, after
* conversion to the typed array element type.
*/
extern JS_FRIEND_API(JSObject*)
JS_NewInt8ArrayFromArray(JSContext* cx, JS::HandleObject array);
extern JS_FRIEND_API(JSObject*)
JS_NewUint8ArrayFromArray(JSContext* cx, JS::HandleObject array);
extern JS_FRIEND_API(JSObject*)
JS_NewUint8ClampedArrayFromArray(JSContext* cx, JS::HandleObject array);
extern JS_FRIEND_API(JSObject*)
JS_NewInt16ArrayFromArray(JSContext* cx, JS::HandleObject array);
extern JS_FRIEND_API(JSObject*)
JS_NewUint16ArrayFromArray(JSContext* cx, JS::HandleObject array);
extern JS_FRIEND_API(JSObject*)
JS_NewInt32ArrayFromArray(JSContext* cx, JS::HandleObject array);
extern JS_FRIEND_API(JSObject*)
JS_NewUint32ArrayFromArray(JSContext* cx, JS::HandleObject array);
extern JS_FRIEND_API(JSObject*)
JS_NewFloat32ArrayFromArray(JSContext* cx, JS::HandleObject array);
extern JS_FRIEND_API(JSObject*)
JS_NewFloat64ArrayFromArray(JSContext* cx, JS::HandleObject array);
/*
* Create a new typed array using the given ArrayBuffer or
* SharedArrayBuffer for storage. The length value is optional; if -1
* is passed, enough elements to use up the remainder of the byte
* array is used as the default value.
*/
extern JS_FRIEND_API(JSObject*)
JS_NewInt8ArrayWithBuffer(JSContext* cx, JS::HandleObject arrayBuffer,
uint32_t byteOffset, int32_t length);
extern JS_FRIEND_API(JSObject*)
JS_NewUint8ArrayWithBuffer(JSContext* cx, JS::HandleObject arrayBuffer,
uint32_t byteOffset, int32_t length);
extern JS_FRIEND_API(JSObject*)
JS_NewUint8ClampedArrayWithBuffer(JSContext* cx, JS::HandleObject arrayBuffer,
uint32_t byteOffset, int32_t length);
extern JS_FRIEND_API(JSObject*)
JS_NewInt16ArrayWithBuffer(JSContext* cx, JS::HandleObject arrayBuffer,
uint32_t byteOffset, int32_t length);
extern JS_FRIEND_API(JSObject*)
JS_NewUint16ArrayWithBuffer(JSContext* cx, JS::HandleObject arrayBuffer,
uint32_t byteOffset, int32_t length);
extern JS_FRIEND_API(JSObject*)
JS_NewInt32ArrayWithBuffer(JSContext* cx, JS::HandleObject arrayBuffer,
uint32_t byteOffset, int32_t length);
extern JS_FRIEND_API(JSObject*)
JS_NewUint32ArrayWithBuffer(JSContext* cx, JS::HandleObject arrayBuffer,
uint32_t byteOffset, int32_t length);
extern JS_FRIEND_API(JSObject*)
JS_NewFloat32ArrayWithBuffer(JSContext* cx, JS::HandleObject arrayBuffer,
uint32_t byteOffset, int32_t length);
extern JS_FRIEND_API(JSObject*)
JS_NewFloat64ArrayWithBuffer(JSContext* cx, JS::HandleObject arrayBuffer,
uint32_t byteOffset, int32_t length);
/**
* Create a new SharedArrayBuffer with the given byte length. This
* may only be called if
* JS::CompartmentCreationOptionsRef(cx).getSharedMemoryAndAtomicsEnabled() is
* true.
*/
extern JS_FRIEND_API(JSObject*)
JS_NewSharedArrayBuffer(JSContext* cx, uint32_t nbytes);
/**
* Create a new ArrayBuffer with the given byte length.
*/
extern JS_FRIEND_API(JSObject*)
JS_NewArrayBuffer(JSContext* cx, uint32_t nbytes);
/**
* Check whether obj supports JS_GetTypedArray* APIs. Note that this may return
* false if a security wrapper is encountered that denies the unwrapping. If
* this test or one of the JS_Is*Array tests succeeds, then it is safe to call
* the various accessor JSAPI calls defined below.
*/
extern JS_FRIEND_API(bool)
JS_IsTypedArrayObject(JSObject* obj);
/**
* Check whether obj supports JS_GetArrayBufferView* APIs. Note that this may
* return false if a security wrapper is encountered that denies the
* unwrapping. If this test or one of the more specific tests succeeds, then it
* is safe to call the various ArrayBufferView accessor JSAPI calls defined
* below.
*/
extern JS_FRIEND_API(bool)
JS_IsArrayBufferViewObject(JSObject* obj);
/*
* Test for specific typed array types (ArrayBufferView subtypes)
*/
extern JS_FRIEND_API(bool)
JS_IsInt8Array(JSObject* obj);
extern JS_FRIEND_API(bool)
JS_IsUint8Array(JSObject* obj);
extern JS_FRIEND_API(bool)
JS_IsUint8ClampedArray(JSObject* obj);
extern JS_FRIEND_API(bool)
JS_IsInt16Array(JSObject* obj);
extern JS_FRIEND_API(bool)
JS_IsUint16Array(JSObject* obj);
extern JS_FRIEND_API(bool)
JS_IsInt32Array(JSObject* obj);
extern JS_FRIEND_API(bool)
JS_IsUint32Array(JSObject* obj);
extern JS_FRIEND_API(bool)
JS_IsFloat32Array(JSObject* obj);
extern JS_FRIEND_API(bool)
JS_IsFloat64Array(JSObject* obj);
/**
* Return the isShared flag of a typed array, which denotes whether
* the underlying buffer is a SharedArrayBuffer.
*
* |obj| must have passed a JS_IsTypedArrayObject/JS_Is*Array test, or somehow
* be known that it would pass such a test: it is a typed array or a wrapper of
* a typed array, and the unwrapping will succeed.
*/
extern JS_FRIEND_API(bool)
JS_GetTypedArraySharedness(JSObject* obj);
/*
* Test for specific typed array types (ArrayBufferView subtypes) and return
* the unwrapped object if so, else nullptr. Never throws.
*/
namespace js {
extern JS_FRIEND_API(JSObject*)
UnwrapInt8Array(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapUint8Array(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapUint8ClampedArray(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapInt16Array(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapUint16Array(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapInt32Array(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapUint32Array(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapFloat32Array(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapFloat64Array(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapArrayBuffer(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapArrayBufferView(JSObject* obj);
extern JS_FRIEND_API(JSObject*)
UnwrapSharedArrayBuffer(JSObject* obj);
namespace detail {
extern JS_FRIEND_DATA(const Class* const) Int8ArrayClassPtr;
extern JS_FRIEND_DATA(const Class* const) Uint8ArrayClassPtr;
extern JS_FRIEND_DATA(const Class* const) Uint8ClampedArrayClassPtr;
extern JS_FRIEND_DATA(const Class* const) Int16ArrayClassPtr;
extern JS_FRIEND_DATA(const Class* const) Uint16ArrayClassPtr;
extern JS_FRIEND_DATA(const Class* const) Int32ArrayClassPtr;
extern JS_FRIEND_DATA(const Class* const) Uint32ArrayClassPtr;
extern JS_FRIEND_DATA(const Class* const) Float32ArrayClassPtr;
extern JS_FRIEND_DATA(const Class* const) Float64ArrayClassPtr;
const size_t TypedArrayLengthSlot = 1;
} // namespace detail
#define JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(Type, type) \
inline void \
Get ## Type ## ArrayLengthAndData(JSObject* obj, uint32_t* length, bool* isSharedMemory, type** data) \
{ \
MOZ_ASSERT(GetObjectClass(obj) == detail::Type ## ArrayClassPtr); \
const JS::Value& lenSlot = GetReservedSlot(obj, detail::TypedArrayLengthSlot); \
*length = mozilla::AssertedCast<uint32_t>(lenSlot.toInt32()); \
*isSharedMemory = JS_GetTypedArraySharedness(obj); \
*data = static_cast<type*>(GetObjectPrivate(obj)); \
}
JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(Int8, int8_t)
JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(Uint8, uint8_t)
JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(Uint8Clamped, uint8_t)
JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(Int16, int16_t)
JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(Uint16, uint16_t)
JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(Int32, int32_t)
JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(Uint32, uint32_t)
JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(Float32, float)
JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(Float64, double)
#undef JS_DEFINE_DATA_AND_LENGTH_ACCESSOR
// This one isn't inlined because it's rather tricky (by dint of having to deal
// with a dozen-plus classes and varying slot layouts.
extern JS_FRIEND_API(void)
GetArrayBufferViewLengthAndData(JSObject* obj, uint32_t* length, bool* isSharedMemory, uint8_t** data);
// This one isn't inlined because there are a bunch of different ArrayBuffer
// classes that would have to be individually handled here.
//
// There is an isShared out argument for API consistency (eases use from DOM).
// It will always be set to false.
extern JS_FRIEND_API(void)
GetArrayBufferLengthAndData(JSObject* obj, uint32_t* length, bool* isSharedMemory, uint8_t** data);
// Ditto for SharedArrayBuffer.
//
// There is an isShared out argument for API consistency (eases use from DOM).
// It will always be set to true.
extern JS_FRIEND_API(void)
GetSharedArrayBufferLengthAndData(JSObject* obj, uint32_t* length, bool* isSharedMemory, uint8_t** data);
} // namespace js
JS_FRIEND_API(uint8_t*)
JS_GetSharedArrayBufferData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
/*
* Unwrap Typed arrays all at once. Return nullptr without throwing if the
* object cannot be viewed as the correct typed array, or the typed array
* object on success, filling both outparameters.
*/
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsInt8Array(JSObject* obj, uint32_t* length, bool* isSharedMemory, int8_t** data);
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsUint8Array(JSObject* obj, uint32_t* length, bool* isSharedMemory, uint8_t** data);
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsUint8ClampedArray(JSObject* obj, uint32_t* length, bool* isSharedMemory, uint8_t** data);
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsInt16Array(JSObject* obj, uint32_t* length, bool* isSharedMemory, int16_t** data);
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsUint16Array(JSObject* obj, uint32_t* length, bool* isSharedMemory, uint16_t** data);
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsInt32Array(JSObject* obj, uint32_t* length, bool* isSharedMemory, int32_t** data);
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsUint32Array(JSObject* obj, uint32_t* length, bool* isSharedMemory, uint32_t** data);
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsFloat32Array(JSObject* obj, uint32_t* length, bool* isSharedMemory, float** data);
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsFloat64Array(JSObject* obj, uint32_t* length, bool* isSharedMemory, double** data);
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsArrayBufferView(JSObject* obj, uint32_t* length, bool* isSharedMemory, uint8_t** data);
/*
* Unwrap an ArrayBuffer, return nullptr if it's a different type.
*/
extern JS_FRIEND_API(JSObject*)
JS_GetObjectAsArrayBuffer(JSObject* obj, uint32_t* length, uint8_t** data);
/*
* Get the type of elements in a typed array, or MaxTypedArrayViewType if a DataView.
*
* |obj| must have passed a JS_IsArrayBufferView/JS_Is*Array test, or somehow
* be known that it would pass such a test: it is an ArrayBufferView or a
* wrapper of an ArrayBufferView, and the unwrapping will succeed.
*/
extern JS_FRIEND_API(js::Scalar::Type)
JS_GetArrayBufferViewType(JSObject* obj);
extern JS_FRIEND_API(js::Scalar::Type)
JS_GetSharedArrayBufferViewType(JSObject* obj);
/*
* Check whether obj supports the JS_GetArrayBuffer* APIs. Note that this may
* return false if a security wrapper is encountered that denies the
* unwrapping. If this test succeeds, then it is safe to call the various
* accessor JSAPI calls defined below.
*/
extern JS_FRIEND_API(bool)
JS_IsArrayBufferObject(JSObject* obj);
extern JS_FRIEND_API(bool)
JS_IsSharedArrayBufferObject(JSObject* obj);
/**
* Return the available byte length of an array buffer.
*
* |obj| must have passed a JS_IsArrayBufferObject test, or somehow be known
* that it would pass such a test: it is an ArrayBuffer or a wrapper of an
* ArrayBuffer, and the unwrapping will succeed.
*/
extern JS_FRIEND_API(uint32_t)
JS_GetArrayBufferByteLength(JSObject* obj);
extern JS_FRIEND_API(uint32_t)
JS_GetSharedArrayBufferByteLength(JSObject* obj);
/**
* Return true if the arrayBuffer contains any data. This will return false for
* ArrayBuffer.prototype and detached ArrayBuffers.
*
* |obj| must have passed a JS_IsArrayBufferObject test, or somehow be known
* that it would pass such a test: it is an ArrayBuffer or a wrapper of an
* ArrayBuffer, and the unwrapping will succeed.
*/
extern JS_FRIEND_API(bool)
JS_ArrayBufferHasData(JSObject* obj);
/**
* Return a pointer to the start of the data referenced by a typed array. The
* data is still owned by the typed array, and should not be modified on
* another thread. Furthermore, the pointer can become invalid on GC (if the
* data is small and fits inside the array's GC header), so callers must take
* care not to hold on across anything that could GC.
*
* |obj| must have passed a JS_IsArrayBufferObject test, or somehow be known
* that it would pass such a test: it is an ArrayBuffer or a wrapper of an
* ArrayBuffer, and the unwrapping will succeed.
*
* |*isSharedMemory| will be set to false, the argument is present to simplify
* its use from code that also interacts with SharedArrayBuffer.
*/
extern JS_FRIEND_API(uint8_t*)
JS_GetArrayBufferData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
/**
* Return the number of elements in a typed array.
*
* |obj| must have passed a JS_IsTypedArrayObject/JS_Is*Array test, or somehow
* be known that it would pass such a test: it is a typed array or a wrapper of
* a typed array, and the unwrapping will succeed.
*/
extern JS_FRIEND_API(uint32_t)
JS_GetTypedArrayLength(JSObject* obj);
/**
* Return the byte offset from the start of an array buffer to the start of a
* typed array view.
*
* |obj| must have passed a JS_IsTypedArrayObject/JS_Is*Array test, or somehow
* be known that it would pass such a test: it is a typed array or a wrapper of
* a typed array, and the unwrapping will succeed.
*/
extern JS_FRIEND_API(uint32_t)
JS_GetTypedArrayByteOffset(JSObject* obj);
/**
* Return the byte length of a typed array.
*
* |obj| must have passed a JS_IsTypedArrayObject/JS_Is*Array test, or somehow
* be known that it would pass such a test: it is a typed array or a wrapper of
* a typed array, and the unwrapping will succeed.
*/
extern JS_FRIEND_API(uint32_t)
JS_GetTypedArrayByteLength(JSObject* obj);
/**
* Check whether obj supports JS_ArrayBufferView* APIs. Note that this may
* return false if a security wrapper is encountered that denies the
* unwrapping.
*/
extern JS_FRIEND_API(bool)
JS_IsArrayBufferViewObject(JSObject* obj);
/**
* More generic name for JS_GetTypedArrayByteLength to cover DataViews as well
*/
extern JS_FRIEND_API(uint32_t)
JS_GetArrayBufferViewByteLength(JSObject* obj);
/*
* Return a pointer to the start of the data referenced by a typed array. The
* data is still owned by the typed array, and should not be modified on
* another thread. Furthermore, the pointer can become invalid on GC (if the
* data is small and fits inside the array's GC header), so callers must take
* care not to hold on across anything that could GC.
*
* |obj| must have passed a JS_Is*Array test, or somehow be known that it would
* pass such a test: it is a typed array or a wrapper of a typed array, and the
* unwrapping will succeed.
*
* |*isSharedMemory| will be set to true if the typed array maps a
* SharedArrayBuffer, otherwise to false.
*/
extern JS_FRIEND_API(int8_t*)
JS_GetInt8ArrayData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
extern JS_FRIEND_API(uint8_t*)
JS_GetUint8ArrayData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
extern JS_FRIEND_API(uint8_t*)
JS_GetUint8ClampedArrayData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
extern JS_FRIEND_API(int16_t*)
JS_GetInt16ArrayData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
extern JS_FRIEND_API(uint16_t*)
JS_GetUint16ArrayData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
extern JS_FRIEND_API(int32_t*)
JS_GetInt32ArrayData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
extern JS_FRIEND_API(uint32_t*)
JS_GetUint32ArrayData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
extern JS_FRIEND_API(float*)
JS_GetFloat32ArrayData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
extern JS_FRIEND_API(double*)
JS_GetFloat64ArrayData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
/**
* Same as above, but for any kind of ArrayBufferView. Prefer the type-specific
* versions when possible.
*/
extern JS_FRIEND_API(void*)
JS_GetArrayBufferViewData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
/**
* Return the ArrayBuffer or SharedArrayBuffer underlying an ArrayBufferView.
* This may return a detached buffer. |obj| must be an object that would
* return true for JS_IsArrayBufferViewObject().
*/
extern JS_FRIEND_API(JSObject*)
JS_GetArrayBufferViewBuffer(JSContext* cx, JS::HandleObject obj, bool* isSharedMemory);
/**
* Detach an ArrayBuffer, causing all associated views to no longer refer to
* the ArrayBuffer's original attached memory.
*
* The |changeData| argument is obsolete and ignored.
*/
extern JS_FRIEND_API(bool)
JS_DetachArrayBuffer(JSContext* cx, JS::HandleObject obj);
/**
* Check whether the obj is a detached ArrayBufferObject. Note that this may
* return false if a security wrapper is encountered that denies the
* unwrapping.
*/
extern JS_FRIEND_API(bool)
JS_IsDetachedArrayBufferObject(JSObject* obj);
/**
* Check whether obj supports JS_GetDataView* APIs.
*/
JS_FRIEND_API(bool)
JS_IsDataViewObject(JSObject* obj);
/**
* Create a new DataView using the given buffer for storage. The given buffer
* must be an ArrayBuffer or SharedArrayBuffer (or a cross-compartment wrapper
* of either type), and the offset and length must fit within the bounds of the
* buffer. Currently, nullptr will be returned and an exception will be thrown
* if these conditions do not hold, but do not depend on that behavior.
*/
JS_FRIEND_API(JSObject*)
JS_NewDataView(JSContext* cx, JS::HandleObject buffer, uint32_t byteOffset, int32_t byteLength);
/**
* Return the byte offset of a data view into its array buffer. |obj| must be a
* DataView.
*
* |obj| must have passed a JS_IsDataViewObject test, or somehow be known that
* it would pass such a test: it is a data view or a wrapper of a data view,
* and the unwrapping will succeed.
*/
JS_FRIEND_API(uint32_t)
JS_GetDataViewByteOffset(JSObject* obj);
/**
* Return the byte length of a data view.
*
* |obj| must have passed a JS_IsDataViewObject test, or somehow be known that
* it would pass such a test: it is a data view or a wrapper of a data view,
* and the unwrapping will succeed. If cx is nullptr, then DEBUG builds may be
* unable to assert when unwrapping should be disallowed.
*/
JS_FRIEND_API(uint32_t)
JS_GetDataViewByteLength(JSObject* obj);
/**
* Return a pointer to the beginning of the data referenced by a DataView.
*
* |obj| must have passed a JS_IsDataViewObject test, or somehow be known that
* it would pass such a test: it is a data view or a wrapper of a data view,
* and the unwrapping will succeed. If cx is nullptr, then DEBUG builds may be
* unable to assert when unwrapping should be disallowed.
*
* |*isSharedMemory| will be set to true if the DataView maps a SharedArrayBuffer,
* otherwise to false.
*/
JS_FRIEND_API(void*)
JS_GetDataViewData(JSObject* obj, bool* isSharedMemory, const JS::AutoCheckCannotGC&);
namespace js {
/**
* Add a watchpoint -- in the Object.prototype.watch sense -- to |obj| for the
* property |id|, using the callable object |callable| as the function to be
* called for notifications.
*
* This is an internal function exposed -- temporarily -- only so that DOM
* proxies can be watchable. Don't use it! We'll soon kill off the
* Object.prototype.{,un}watch functions, at which point this will go too.
*/
extern JS_FRIEND_API(bool)
WatchGuts(JSContext* cx, JS::HandleObject obj, JS::HandleId id, JS::HandleObject callable);
/**
* Remove a watchpoint -- in the Object.prototype.watch sense -- from |obj| for
* the property |id|.
*
* This is an internal function exposed -- temporarily -- only so that DOM
* proxies can be watchable. Don't use it! We'll soon kill off the
* Object.prototype.{,un}watch functions, at which point this will go too.
*/
extern JS_FRIEND_API(bool)
UnwatchGuts(JSContext* cx, JS::HandleObject obj, JS::HandleId id);
namespace jit {
enum class InlinableNative : uint16_t;
} // namespace jit
} // namespace js
/**
* A class, expected to be passed by value, which represents the CallArgs for a
* JSJitGetterOp.
*/
class JSJitGetterCallArgs : protected JS::MutableHandleValue
{
public:
explicit JSJitGetterCallArgs(const JS::CallArgs& args)
: JS::MutableHandleValue(args.rval())
{}
explicit JSJitGetterCallArgs(JS::RootedValue* rooted)
: JS::MutableHandleValue(rooted)
{}
JS::MutableHandleValue rval() {
return *this;
}
};
/**
* A class, expected to be passed by value, which represents the CallArgs for a
* JSJitSetterOp.
*/
class JSJitSetterCallArgs : protected JS::MutableHandleValue
{
public:
explicit JSJitSetterCallArgs(const JS::CallArgs& args)
: JS::MutableHandleValue(args[0])
{}
JS::MutableHandleValue operator[](unsigned i) {
MOZ_ASSERT(i == 0);
return *this;
}
unsigned length() const { return 1; }
// Add get() or maybe hasDefined() as needed
};
struct JSJitMethodCallArgsTraits;
/**
* A class, expected to be passed by reference, which represents the CallArgs
* for a JSJitMethodOp.
*/
class JSJitMethodCallArgs : protected JS::detail::CallArgsBase<JS::detail::NoUsedRval>
{
private:
typedef JS::detail::CallArgsBase<JS::detail::NoUsedRval> Base;
friend struct JSJitMethodCallArgsTraits;
public:
explicit JSJitMethodCallArgs(const JS::CallArgs& args) {
argv_ = args.array();
argc_ = args.length();
}
JS::MutableHandleValue rval() const {
return Base::rval();
}
unsigned length() const { return Base::length(); }
JS::MutableHandleValue operator[](unsigned i) const {
return Base::operator[](i);
}
bool hasDefined(unsigned i) const {
return Base::hasDefined(i);
}
JSObject& callee() const {
// We can't use Base::callee() because that will try to poke at
// this->usedRval_, which we don't have.
return argv_[-2].toObject();
}
JS::HandleValue get(unsigned i) const {
return Base::get(i);
}
};
struct JSJitMethodCallArgsTraits
{
static const size_t offsetOfArgv = offsetof(JSJitMethodCallArgs, argv_);
static const size_t offsetOfArgc = offsetof(JSJitMethodCallArgs, argc_);
};
typedef bool
(* JSJitGetterOp)(JSContext* cx, JS::HandleObject thisObj,
void* specializedThis, JSJitGetterCallArgs args);
typedef bool
(* JSJitSetterOp)(JSContext* cx, JS::HandleObject thisObj,
void* specializedThis, JSJitSetterCallArgs args);
typedef bool
(* JSJitMethodOp)(JSContext* cx, JS::HandleObject thisObj,
void* specializedThis, const JSJitMethodCallArgs& args);
/**
* This struct contains metadata passed from the DOM to the JS Engine for JIT
* optimizations on DOM property accessors. Eventually, this should be made
* available to general JSAPI users, but we are not currently ready to do so.
*/
struct JSJitInfo {
enum OpType {
Getter,
Setter,
Method,
StaticMethod,
InlinableNative,
IgnoresReturnValueNative,
// Must be last
OpTypeCount
};
enum ArgType {
// Basic types
String = (1 << 0),
Integer = (1 << 1), // Only 32-bit or less
Double = (1 << 2), // Maybe we want to add Float sometime too
Boolean = (1 << 3),
Object = (1 << 4),
Null = (1 << 5),
// And derived types
Numeric = Integer | Double,
// Should "Primitive" use the WebIDL definition, which
// excludes string and null, or the typical JS one that includes them?
Primitive = Numeric | Boolean | Null | String,
ObjectOrNull = Object | Null,
Any = ObjectOrNull | Primitive,
// Our sentinel value.
ArgTypeListEnd = (1 << 31)
};
static_assert(Any & String, "Any must include String.");
static_assert(Any & Integer, "Any must include Integer.");
static_assert(Any & Double, "Any must include Double.");
static_assert(Any & Boolean, "Any must include Boolean.");
static_assert(Any & Object, "Any must include Object.");
static_assert(Any & Null, "Any must include Null.");
/**
* An enum that describes what this getter/setter/method aliases. This
* determines what things can be hoisted past this call, and if this
* call is movable what it can be hoisted past.
*/
enum AliasSet {
/**
* Alias nothing: a constant value, getting it can't affect any other
* values, nothing can affect it.
*/
AliasNone,
/**
* Alias things that can modify the DOM but nothing else. Doing the
* call can't affect the behavior of any other function.
*/
AliasDOMSets,
/**
* Alias the world. Calling this can change arbitrary values anywhere
* in the system. Most things fall in this bucket.
*/
AliasEverything,
/** Must be last. */
AliasSetCount
};
bool needsOuterizedThisObject() const
{
return type() != Getter && type() != Setter;
}
bool isTypedMethodJitInfo() const
{
return isTypedMethod;
}
OpType type() const
{
return OpType(type_);
}
AliasSet aliasSet() const
{
return AliasSet(aliasSet_);
}
JSValueType returnType() const
{
return JSValueType(returnType_);
}
union {
JSJitGetterOp getter;
JSJitSetterOp setter;
JSJitMethodOp method;
/** A DOM static method, used for Promise wrappers */
JSNative staticMethod;
JSNative ignoresReturnValueMethod;
};
static unsigned offsetOfIgnoresReturnValueNative() {
return offsetof(JSJitInfo, ignoresReturnValueMethod);
}
union {
uint16_t protoID;
js::jit::InlinableNative inlinableNative;
};
union {
uint16_t depth;
// Additional opcode for some InlinableNative functions.
uint16_t nativeOp;
};
// These fields are carefully packed to take up 4 bytes. If you need more
// bits for whatever reason, please see if you can steal bits from existing
// fields before adding more members to this structure.
#define JITINFO_OP_TYPE_BITS 4
#define JITINFO_ALIAS_SET_BITS 4
#define JITINFO_RETURN_TYPE_BITS 8
#define JITINFO_SLOT_INDEX_BITS 10
/** The OpType that says what sort of function we are. */
uint32_t type_ : JITINFO_OP_TYPE_BITS;
/**
* The alias set for this op. This is a _minimal_ alias set; in
* particular for a method it does not include whatever argument
* conversions might do. That's covered by argTypes and runtime
* analysis of the actual argument types being passed in.
*/
uint32_t aliasSet_ : JITINFO_ALIAS_SET_BITS;
/** The return type tag. Might be JSVAL_TYPE_UNKNOWN. */
uint32_t returnType_ : JITINFO_RETURN_TYPE_BITS;
static_assert(OpTypeCount <= (1 << JITINFO_OP_TYPE_BITS),
"Not enough space for OpType");
static_assert(AliasSetCount <= (1 << JITINFO_ALIAS_SET_BITS),
"Not enough space for AliasSet");
static_assert((sizeof(JSValueType) * 8) <= JITINFO_RETURN_TYPE_BITS,
"Not enough space for JSValueType");
#undef JITINFO_RETURN_TYPE_BITS
#undef JITINFO_ALIAS_SET_BITS
#undef JITINFO_OP_TYPE_BITS
/** Is op fallible? False in setters. */
uint32_t isInfallible : 1;
/**
* Is op movable? To be movable the op must
* not AliasEverything, but even that might
* not be enough (e.g. in cases when it can
* throw or is explicitly not movable).
*/
uint32_t isMovable : 1;
/**
* Can op be dead-code eliminated? Again, this
* depends on whether the op can throw, in
* addition to the alias set.
*/
uint32_t isEliminatable : 1;
// XXXbz should we have a JSValueType for the type of the member?
/**
* True if this is a getter that can always
* get the value from a slot of the "this" object.
*/
uint32_t isAlwaysInSlot : 1;
/**
* True if this is a getter that can sometimes (if the slot doesn't contain
* UndefinedValue()) get the value from a slot of the "this" object.
*/
uint32_t isLazilyCachedInSlot : 1;
/** True if this is an instance of JSTypedMethodJitInfo. */
uint32_t isTypedMethod : 1;
/**
* If isAlwaysInSlot or isSometimesInSlot is true,
* the index of the slot to get the value from.
* Otherwise 0.
*/
uint32_t slotIndex : JITINFO_SLOT_INDEX_BITS;
static const size_t maxSlotIndex = (1 << JITINFO_SLOT_INDEX_BITS) - 1;
#undef JITINFO_SLOT_INDEX_BITS
};
static_assert(sizeof(JSJitInfo) == (sizeof(void*) + 2 * sizeof(uint32_t)),
"There are several thousand instances of JSJitInfo stored in "
"a binary. Please don't increase its space requirements without "
"verifying that there is no other way forward (better packing, "
"smaller datatypes for fields, subclassing, etc.).");
struct JSTypedMethodJitInfo
{
// We use C-style inheritance here, rather than C++ style inheritance
// because not all compilers support brace-initialization for non-aggregate
// classes. Using C++ style inheritance and constructors instead of
// brace-initialization would also force the creation of static
// constructors (on some compilers) when JSJitInfo and JSTypedMethodJitInfo
// structures are declared. Since there can be several thousand of these
// structures present and we want to have roughly equivalent performance
// across a range of compilers, we do things manually.
JSJitInfo base;
const JSJitInfo::ArgType* const argTypes; /* For a method, a list of sets of
types that the function
expects. This can be used,
for example, to figure out
when argument coercions can
have side-effects. */
};
namespace js {
static MOZ_ALWAYS_INLINE shadow::Function*
FunctionObjectToShadowFunction(JSObject* fun)
{
MOZ_ASSERT(GetObjectClass(fun) == FunctionClassPtr);
return reinterpret_cast<shadow::Function*>(fun);
}
/* Statically asserted in jsfun.h. */
static const unsigned JS_FUNCTION_INTERPRETED_BITS = 0x0201;
// Return whether the given function object is native.
static MOZ_ALWAYS_INLINE bool
FunctionObjectIsNative(JSObject* fun)
{
return !(FunctionObjectToShadowFunction(fun)->flags & JS_FUNCTION_INTERPRETED_BITS);
}
static MOZ_ALWAYS_INLINE JSNative
GetFunctionObjectNative(JSObject* fun)
{
MOZ_ASSERT(FunctionObjectIsNative(fun));
return FunctionObjectToShadowFunction(fun)->native;
}
} // namespace js
static MOZ_ALWAYS_INLINE const JSJitInfo*
FUNCTION_VALUE_TO_JITINFO(const JS::Value& v)
{
MOZ_ASSERT(js::FunctionObjectIsNative(&v.toObject()));
return js::FunctionObjectToShadowFunction(&v.toObject())->jitinfo;
}
static MOZ_ALWAYS_INLINE void
SET_JITINFO(JSFunction * func, const JSJitInfo* info)
{
js::shadow::Function* fun = reinterpret_cast<js::shadow::Function*>(func);
MOZ_ASSERT(!(fun->flags & js::JS_FUNCTION_INTERPRETED_BITS));
fun->jitinfo = info;
}
/*
* Engine-internal extensions of jsid. This code is here only until we
* eliminate Gecko's dependencies on it!
*/
static MOZ_ALWAYS_INLINE jsid
JSID_FROM_BITS(size_t bits)
{
jsid id;
JSID_BITS(id) = bits;
return id;
}
namespace js {
namespace detail {
bool IdMatchesAtom(jsid id, JSAtom* atom);
} // namespace detail
} // namespace js
/**
* Must not be used on atoms that are representable as integer jsids.
* Prefer NameToId or AtomToId over this function:
*
* A PropertyName is an atom that does not contain an integer in the range
* [0, UINT32_MAX]. However, jsid can only hold an integer in the range
* [0, JSID_INT_MAX] (where JSID_INT_MAX == 2^31-1). Thus, for the range of
* integers (JSID_INT_MAX, UINT32_MAX], to represent as a jsid 'id', it must be
* the case JSID_IS_ATOM(id) and !JSID_TO_ATOM(id)->isPropertyName(). In most
* cases when creating a jsid, code does not have to care about this corner
* case because:
*
* - When given an arbitrary JSAtom*, AtomToId must be used, which checks for
* integer atoms representable as integer jsids, and does this conversion.
*
* - When given a PropertyName*, NameToId can be used which which does not need
* to do any dynamic checks.
*
* Thus, it is only the rare third case which needs this function, which
* handles any JSAtom* that is known not to be representable with an int jsid.
*/
static MOZ_ALWAYS_INLINE jsid
NON_INTEGER_ATOM_TO_JSID(JSAtom* atom)
{
MOZ_ASSERT(((size_t)atom & 0x7) == 0);
jsid id = JSID_FROM_BITS((size_t)atom);
MOZ_ASSERT(js::detail::IdMatchesAtom(id, atom));
return id;
}
/* All strings stored in jsids are atomized, but are not necessarily property names. */
static MOZ_ALWAYS_INLINE bool
JSID_IS_ATOM(jsid id)
{
return JSID_IS_STRING(id);
}
static MOZ_ALWAYS_INLINE bool
JSID_IS_ATOM(jsid id, JSAtom* atom)
{
return id == JSID_FROM_BITS((size_t)atom);
}
static MOZ_ALWAYS_INLINE JSAtom*
JSID_TO_ATOM(jsid id)
{
return (JSAtom*)JSID_TO_STRING(id);
}
JS_STATIC_ASSERT(sizeof(jsid) == sizeof(void*));
namespace js {
static MOZ_ALWAYS_INLINE JS::Value
IdToValue(jsid id)
{
if (JSID_IS_STRING(id))
return JS::StringValue(JSID_TO_STRING(id));
if (JSID_IS_INT(id))
return JS::Int32Value(JSID_TO_INT(id));
if (JSID_IS_SYMBOL(id))
return JS::SymbolValue(JSID_TO_SYMBOL(id));
MOZ_ASSERT(JSID_IS_VOID(id));
return JS::UndefinedValue();
}
/**
* If the embedder has registered a ScriptEnvironmentPreparer,
* PrepareScriptEnvironmentAndInvoke will call the preparer's 'invoke' method
* with the given |closure|, with the assumption that the preparer will set up
* any state necessary to run script in |scope|, invoke |closure| with a valid
* JSContext*, report any exceptions thrown from the closure, and return.
*
* If no preparer is registered, PrepareScriptEnvironmentAndInvoke will assert
* that |rt| has exactly one JSContext associated with it, enter the compartment
* of |scope| on that context, and invoke |closure|.
*
* In both cases, PrepareScriptEnvironmentAndInvoke will report any exceptions
* that are thrown by the closure. Consumers who want to propagate back
* whether the closure succeeded should do so via members of the closure
* itself.
*/
struct ScriptEnvironmentPreparer {
struct Closure {
virtual bool operator()(JSContext* cx) = 0;
};
virtual void invoke(JS::HandleObject scope, Closure& closure) = 0;
};
extern JS_FRIEND_API(void)
PrepareScriptEnvironmentAndInvoke(JSContext* cx, JS::HandleObject scope,
ScriptEnvironmentPreparer::Closure& closure);
JS_FRIEND_API(void)
SetScriptEnvironmentPreparer(JSContext* cx, ScriptEnvironmentPreparer* preparer);
enum CTypesActivityType {
CTYPES_CALL_BEGIN,
CTYPES_CALL_END,
CTYPES_CALLBACK_BEGIN,
CTYPES_CALLBACK_END
};
typedef void
(* CTypesActivityCallback)(JSContext* cx, CTypesActivityType type);
/**
* Sets a callback that is run whenever js-ctypes is about to be used when
* calling into C.
*/
JS_FRIEND_API(void)
SetCTypesActivityCallback(JSContext* cx, CTypesActivityCallback cb);
class MOZ_RAII JS_FRIEND_API(AutoCTypesActivityCallback) {
private:
JSContext* cx;
CTypesActivityCallback callback;
CTypesActivityType endType;
MOZ_DECL_USE_GUARD_OBJECT_NOTIFIER
public:
AutoCTypesActivityCallback(JSContext* cx, CTypesActivityType beginType,
CTypesActivityType endType
MOZ_GUARD_OBJECT_NOTIFIER_PARAM);
~AutoCTypesActivityCallback() {
DoEndCallback();
}
void DoEndCallback() {
if (callback) {
callback(cx, endType);
callback = nullptr;
}
}
};
// Abstract base class for objects that build allocation metadata for JavaScript
// values.
struct AllocationMetadataBuilder {
AllocationMetadataBuilder() { }
// Return a metadata object for the newly constructed object |obj|, or
// nullptr if there's no metadata to attach.
//
// Implementations should treat all errors as fatal; there is no way to
// report errors from this callback. In particular, the caller provides an
// oomUnsafe for overriding implementations to use.
virtual JSObject* build(JSContext* cx, JS::HandleObject obj,
AutoEnterOOMUnsafeRegion& oomUnsafe) const
{
return nullptr;
}
};
/**
* Specify a callback to invoke when creating each JS object in the current
* compartment, which may return a metadata object to associate with the
* object.
*/
JS_FRIEND_API(void)
SetAllocationMetadataBuilder(JSContext* cx, const AllocationMetadataBuilder *callback);
/** Get the metadata associated with an object. */
JS_FRIEND_API(JSObject*)
GetAllocationMetadata(JSObject* obj);
JS_FRIEND_API(bool)
GetElementsWithAdder(JSContext* cx, JS::HandleObject obj, JS::HandleObject receiver,
uint32_t begin, uint32_t end, js::ElementAdder* adder);
JS_FRIEND_API(bool)
ForwardToNative(JSContext* cx, JSNative native, const JS::CallArgs& args);
/**
* Helper function for HTMLDocument and HTMLFormElement.
*
* These are the only two interfaces that have [OverrideBuiltins], a named
* getter, and no named setter. They're implemented as proxies with a custom
* getOwnPropertyDescriptor() method. Unfortunately, overriding
* getOwnPropertyDescriptor() automatically affects the behavior of set(),
* which normally is just common sense but is *not* desired for these two
* interfaces.
*
* The fix is for these two interfaces to override set() to ignore the
* getOwnPropertyDescriptor() override.
*
* SetPropertyIgnoringNamedGetter is exposed to make it easier to override
* set() in this way. It carries out all the steps of BaseProxyHandler::set()
* except the initial getOwnPropertyDescriptor() call. The caller must supply
* that descriptor as the 'ownDesc' parameter.
*
* Implemented in proxy/BaseProxyHandler.cpp.
*/
JS_FRIEND_API(bool)
SetPropertyIgnoringNamedGetter(JSContext* cx, JS::HandleObject obj, JS::HandleId id,
JS::HandleValue v, JS::HandleValue receiver,
JS::Handle<JS::PropertyDescriptor> ownDesc,
JS::ObjectOpResult& result);
// This function is for one specific use case, please don't use this for anything else!
extern JS_FRIEND_API(bool)
ExecuteInGlobalAndReturnScope(JSContext* cx, JS::HandleObject obj, JS::HandleScript script,
JS::MutableHandleObject scope);
#if defined(XP_WIN) && defined(_WIN64)
// Parameters use void* types to avoid #including windows.h. The return value of
// this function is returned from the exception handler.
typedef long
(*JitExceptionHandler)(void* exceptionRecord, // PEXECTION_RECORD
void* context); // PCONTEXT
/**
* Windows uses "structured exception handling" to handle faults. When a fault
* occurs, the stack is searched for a handler (similar to C++ exception
* handling). If the search does not find a handler, the "unhandled exception
* filter" is called. Breakpad uses the unhandled exception filter to do crash
* reporting. Unfortunately, on Win64, JIT code on the stack completely throws
* off this unwinding process and prevents the unhandled exception filter from
* being called. The reason is that Win64 requires unwind information be
* registered for all code regions and JIT code has none. While it is possible
* to register full unwind information for JIT code, this is a lot of work (one
* has to be able to recover the frame pointer at any PC) so instead we register
* a handler for all JIT code that simply calls breakpad's unhandled exception
* filter (which will perform crash reporting and then terminate the process).
* This would be wrong if there was an outer __try block that expected to handle
* the fault, but this is not generally allowed.
*
* Gecko must call SetJitExceptionFilter before any JIT code is compiled and
* only once per process.
*/
extern JS_FRIEND_API(void)
SetJitExceptionHandler(JitExceptionHandler handler);
#endif
/**
* Get the nearest enclosing with environment object for a given function. If
* the function is not scripted or is not enclosed by a with scope, returns
* the global.
*/
extern JS_FRIEND_API(JSObject*)
GetNearestEnclosingWithEnvironmentObjectForFunction(JSFunction* fun);
/**
* Get the first SavedFrame object in this SavedFrame stack whose principals are
* subsumed by the cx's principals. If there is no such frame, return nullptr.
*
* Do NOT pass a non-SavedFrame object here.
*
* The savedFrame and cx do not need to be in the same compartment.
*/
extern JS_FRIEND_API(JSObject*)
GetFirstSubsumedSavedFrame(JSContext* cx, JS::HandleObject savedFrame, JS::SavedFrameSelfHosted selfHosted);
extern JS_FRIEND_API(bool)
ReportIsNotFunction(JSContext* cx, JS::HandleValue v);
extern JS_FRIEND_API(JSObject*)
ConvertArgsToArray(JSContext* cx, const JS::CallArgs& args);
/**
* Window and WindowProxy
*
* The functions below have to do with Windows and WindowProxies. There's an
* invariant that actual Window objects (the global objects of web pages) are
* never directly exposed to script. Instead we often substitute a WindowProxy.
*
* The environment chain, on the other hand, contains the Window and never its
* WindowProxy.
*
* As a result, we have calls to these "substitute-this-object-for-that-object"
* functions sprinkled at apparently arbitrary (but actually *very* carefully
* and nervously selected) places throughout the engine and indeed the
* universe.
*/
/**
* Tell the JS engine which Class is used for WindowProxy objects. Used by the
* functions below.
*/
extern JS_FRIEND_API(void)
SetWindowProxyClass(JSContext* cx, const Class* clasp);
/**
* Associates a WindowProxy with a Window (global object). `windowProxy` must
* have the Class set by SetWindowProxyClass.
*/
extern JS_FRIEND_API(void)
SetWindowProxy(JSContext* cx, JS::HandleObject global, JS::HandleObject windowProxy);
namespace detail {
JS_FRIEND_API(bool)
IsWindowSlow(JSObject* obj);
JS_FRIEND_API(JSObject*)
ToWindowProxyIfWindowSlow(JSObject* obj);
} // namespace detail
/**
* Returns true iff `obj` is a global object with an associated WindowProxy,
* see SetWindowProxy.
*/
inline bool
IsWindow(JSObject* obj)
{
if (GetObjectClass(obj)->flags & JSCLASS_IS_GLOBAL)
return detail::IsWindowSlow(obj);
return false;
}
/**
* Returns true iff `obj` has the WindowProxy Class (see SetWindowProxyClass).
*/
JS_FRIEND_API(bool)
IsWindowProxy(JSObject* obj);
/**
* If `obj` is a Window, get its associated WindowProxy (or a CCW or dead
* wrapper if the page was navigated away from), else return `obj`. This
* function is infallible and never returns nullptr.
*/
MOZ_ALWAYS_INLINE JSObject*
ToWindowProxyIfWindow(JSObject* obj)
{
if (GetObjectClass(obj)->flags & JSCLASS_IS_GLOBAL)
return detail::ToWindowProxyIfWindowSlow(obj);
return obj;
}
/**
* If `obj` is a WindowProxy, get its associated Window (the compartment's
* global), else return `obj`. This function is infallible and never returns
* nullptr.
*/
extern JS_FRIEND_API(JSObject*)
ToWindowIfWindowProxy(JSObject* obj);
// Create and add the Intl.PluralRules constructor function to the provided
// object. This function throws if called more than once per realm/global
// object.
extern bool
AddPluralRulesConstructor(JSContext* cx, JS::Handle<JSObject*> intl);
// Create and add the Intl.MozDateTimeFormat constructor function to the provided
// object.
//
// This custom date/time formatter constructor gives users the ability
// to specify a custom format pattern. This pattern is passed *directly*
// to ICU with NO SYNTAX PARSING OR VALIDATION WHATSOEVER. ICU appears to
// have a a modicum of testing of this, and it won't fall over completely
// if passed bad input. But the current behavior is entirely under-specified
// and emphatically not shippable on the web, and it *must* be fixed before
// this functionality can be exposed in the real world. (There are also some
// questions about whether the format exposed here is the *right* one to
// standardize, that will also need to be resolved to ship this.)
extern bool
AddMozDateTimeFormatConstructor(JSContext* cx, JS::Handle<JSObject*> intl);
class MOZ_STACK_CLASS JS_FRIEND_API(AutoAssertNoContentJS)
{
public:
explicit AutoAssertNoContentJS(JSContext* cx);
~AutoAssertNoContentJS();
private:
JSContext* context_;
bool prevAllowContentJS_;
};
// Turn on assertions so that we assert that
// !comp->validAccessPtr || *comp->validAccessPtr
// is true for every |comp| that we run JS code in. The compartment's validAccessPtr
// is set via SetCompartmentValidAccessPtr.
extern JS_FRIEND_API(void)
EnableAccessValidation(JSContext* cx, bool enabled);
// See EnableAccessValidation above. The caller must guarantee that accessp will
// live at least as long as |global| is alive. The JS engine reads accessp from
// threads that are allowed to run code on |global|, so all changes to *accessp
// should be made from whichever thread owns |global| at a given time.
extern JS_FRIEND_API(void)
SetCompartmentValidAccessPtr(JSContext* cx, JS::HandleObject global, bool* accessp);
} /* namespace js */
class NativeProfiler
{
public:
virtual ~NativeProfiler() {};
virtual void sampleNative(void* addr, uint32_t size) = 0;
virtual void removeNative(void* addr) = 0;
virtual void reset() = 0;
};
class GCHeapProfiler
{
public:
virtual ~GCHeapProfiler() {};
virtual void sampleTenured(void* addr, uint32_t size) = 0;
virtual void sampleNursery(void* addr, uint32_t size) = 0;
virtual void markTenuredStart() = 0;
virtual void markTenured(void* addr) = 0;
virtual void sweepTenured() = 0;
virtual void sweepNursery() = 0;
virtual void moveNurseryToTenured(void* addrOld, void* addrNew) = 0;
virtual void reset() = 0;
};
class MemProfiler
{
static mozilla::Atomic<uint32_t, mozilla::Relaxed> sActiveProfilerCount;
static JS_FRIEND_DATA(NativeProfiler*) sNativeProfiler;
static GCHeapProfiler* GetGCHeapProfiler(void* addr);
static GCHeapProfiler* GetGCHeapProfiler(JSRuntime* runtime);
static NativeProfiler* GetNativeProfiler() {
return sNativeProfiler;
}
GCHeapProfiler* mGCHeapProfiler;
JSRuntime* mRuntime;
public:
explicit MemProfiler(JSRuntime* aRuntime) : mGCHeapProfiler(nullptr), mRuntime(aRuntime) {}
JS_FRIEND_API(void) start(GCHeapProfiler* aGCHeapProfiler);
JS_FRIEND_API(void) stop();
GCHeapProfiler* getGCHeapProfiler() const {
return mGCHeapProfiler;
}
static MOZ_ALWAYS_INLINE bool enabled() {
return sActiveProfilerCount > 0;
}
static JS_FRIEND_API(MemProfiler*) GetMemProfiler(JSContext* context);
static void SetNativeProfiler(NativeProfiler* aProfiler) {
sNativeProfiler = aProfiler;
}
static MOZ_ALWAYS_INLINE void SampleNative(void* addr, uint32_t size) {
JS::AutoSuppressGCAnalysis nogc;
if (MOZ_LIKELY(!enabled()))
return;
NativeProfiler* profiler = GetNativeProfiler();
if (profiler)
profiler->sampleNative(addr, size);
}
static MOZ_ALWAYS_INLINE void SampleTenured(void* addr, uint32_t size) {
JS::AutoSuppressGCAnalysis nogc;
if (MOZ_LIKELY(!enabled()))
return;
GCHeapProfiler* profiler = GetGCHeapProfiler(addr);
if (profiler)
profiler->sampleTenured(addr, size);
}
static MOZ_ALWAYS_INLINE void SampleNursery(void* addr, uint32_t size) {
JS::AutoSuppressGCAnalysis nogc;
if (MOZ_LIKELY(!enabled()))
return;
GCHeapProfiler* profiler = GetGCHeapProfiler(addr);
if (profiler)
profiler->sampleNursery(addr, size);
}
static MOZ_ALWAYS_INLINE void RemoveNative(void* addr) {
JS::AutoSuppressGCAnalysis nogc;
if (MOZ_LIKELY(!enabled()))
return;
NativeProfiler* profiler = GetNativeProfiler();
if (profiler)
profiler->removeNative(addr);
}
static MOZ_ALWAYS_INLINE void MarkTenuredStart(JSRuntime* runtime) {
JS::AutoSuppressGCAnalysis nogc;
if (MOZ_LIKELY(!enabled()))
return;
GCHeapProfiler* profiler = GetGCHeapProfiler(runtime);
if (profiler)
profiler->markTenuredStart();
}
static MOZ_ALWAYS_INLINE void MarkTenured(void* addr) {
JS::AutoSuppressGCAnalysis nogc;
if (MOZ_LIKELY(!enabled()))
return;
GCHeapProfiler* profiler = GetGCHeapProfiler(addr);
if (profiler)
profiler->markTenured(addr);
}
static MOZ_ALWAYS_INLINE void SweepTenured(JSRuntime* runtime) {
JS::AutoSuppressGCAnalysis nogc;
if (MOZ_LIKELY(!enabled()))
return;
GCHeapProfiler* profiler = GetGCHeapProfiler(runtime);
if (profiler)
profiler->sweepTenured();
}
static MOZ_ALWAYS_INLINE void SweepNursery(JSRuntime* runtime) {
JS::AutoSuppressGCAnalysis nogc;
if (MOZ_LIKELY(!enabled()))
return;
GCHeapProfiler* profiler = GetGCHeapProfiler(runtime);
if (profiler)
profiler->sweepNursery();
}
static MOZ_ALWAYS_INLINE void MoveNurseryToTenured(void* addrOld, void* addrNew) {
JS::AutoSuppressGCAnalysis nogc;
if (MOZ_LIKELY(!enabled()))
return;
GCHeapProfiler* profiler = GetGCHeapProfiler(addrOld);
if (profiler)
profiler->moveNurseryToTenured(addrOld, addrNew);
}
};
#endif /* jsfriendapi_h */
