/* -*- 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 jscntxtinlines_h
#define jscntxtinlines_h
#include "jscntxt.h"
#include "jscompartment.h"
#include "jsiter.h"
#include "builtin/Object.h"
#include "jit/JitFrames.h"
#include "vm/ForkJoin.h"
#include "vm/HelperThreads.h"
#include "vm/Interpreter.h"
#include "vm/ProxyObject.h"
#include "vm/Symbol.h"
#include "gc/ForkJoinNursery-inl.h"
namespace js {
#ifdef JS_CRASH_DIAGNOSTICS
class CompartmentChecker
{
JSCompartment *compartment;
public:
explicit CompartmentChecker(ExclusiveContext *cx)
: compartment(cx->compartment())
{
#ifdef DEBUG
// In debug builds, make sure the embedder passed the cx it claimed it
// was going to use.
JSContext *activeContext = nullptr;
if (cx->isJSContext())
activeContext = cx->asJSContext()->runtime()->activeContext;
MOZ_ASSERT_IF(activeContext, cx == activeContext);
#endif
}
/*
* Set a breakpoint here (break js::CompartmentChecker::fail) to debug
* compartment mismatches.
*/
static void fail(JSCompartment *c1, JSCompartment *c2) {
printf("*** Compartment mismatch %p vs. %p\n", (void *) c1, (void *) c2);
MOZ_CRASH();
}
static void fail(JS::Zone *z1, JS::Zone *z2) {
printf("*** Zone mismatch %p vs. %p\n", (void *) z1, (void *) z2);
MOZ_CRASH();
}
/* Note: should only be used when neither c1 nor c2 may be the atoms compartment. */
static void check(JSCompartment *c1, JSCompartment *c2) {
MOZ_ASSERT(!c1->runtimeFromAnyThread()->isAtomsCompartment(c1));
MOZ_ASSERT(!c2->runtimeFromAnyThread()->isAtomsCompartment(c2));
if (c1 != c2)
fail(c1, c2);
}
void check(JSCompartment *c) {
if (c && !compartment->runtimeFromAnyThread()->isAtomsCompartment(c)) {
if (!compartment)
compartment = c;
else if (c != compartment)
fail(compartment, c);
}
}
void checkZone(JS::Zone *z) {
if (compartment && z != compartment->zone())
fail(compartment->zone(), z);
}
void check(JSObject *obj) {
if (obj)
check(obj->compartment());
}
template<typename T>
void check(const Rooted<T>& rooted) {
check(rooted.get());
}
template<typename T>
void check(Handle<T> handle) {
check(handle.get());
}
void check(JSString *str) {
if (!str->isAtom())
checkZone(str->zone());
}
void check(const js::Value &v) {
if (v.isObject())
check(&v.toObject());
else if (v.isString())
check(v.toString());
}
void check(const ValueArray &arr) {
for (size_t i = 0; i < arr.length; i++)
check(arr.array[i]);
}
void check(const JSValueArray &arr) {
for (size_t i = 0; i < arr.length; i++)
check(arr.array[i]);
}
void check(const JS::HandleValueArray &arr) {
for (size_t i = 0; i < arr.length(); i++)
check(arr[i]);
}
void check(const CallArgs &args) {
for (Value *p = args.base(); p != args.end(); ++p)
check(*p);
}
void check(jsid id) {}
void check(JSScript *script) {
if (script)
check(script->compartment());
}
void check(InterpreterFrame *fp);
void check(AbstractFramePtr frame);
void check(SavedStacks *stacks);
};
#endif /* JS_CRASH_DIAGNOSTICS */
/*
* Don't perform these checks when called from a finalizer. The checking
* depends on other objects not having been swept yet.
*/
#define START_ASSERT_SAME_COMPARTMENT() \
if (!cx->isExclusiveContext()) \
return; \
if (cx->isJSContext() && cx->asJSContext()->runtime()->isHeapBusy()) \
return; \
CompartmentChecker c(cx->asExclusiveContext())
template <class T1> inline void
assertSameCompartment(ThreadSafeContext *cx, const T1 &t1)
{
#ifdef JS_CRASH_DIAGNOSTICS
START_ASSERT_SAME_COMPARTMENT();
c.check(t1);
#endif
}
template <class T1> inline void
assertSameCompartmentDebugOnly(ThreadSafeContext *cx, const T1 &t1)
{
#if defined(DEBUG) && defined(JS_CRASH_DIAGNOSTICS)
START_ASSERT_SAME_COMPARTMENT();
c.check(t1);
#endif
}
template <class T1, class T2> inline void
assertSameCompartment(ThreadSafeContext *cx, const T1 &t1, const T2 &t2)
{
#ifdef JS_CRASH_DIAGNOSTICS
START_ASSERT_SAME_COMPARTMENT();
c.check(t1);
c.check(t2);
#endif
}
template <class T1, class T2, class T3> inline void
assertSameCompartment(ThreadSafeContext *cx, const T1 &t1, const T2 &t2, const T3 &t3)
{
#ifdef JS_CRASH_DIAGNOSTICS
START_ASSERT_SAME_COMPARTMENT();
c.check(t1);
c.check(t2);
c.check(t3);
#endif
}
template <class T1, class T2, class T3, class T4> inline void
assertSameCompartment(ThreadSafeContext *cx,
const T1 &t1, const T2 &t2, const T3 &t3, const T4 &t4)
{
#ifdef JS_CRASH_DIAGNOSTICS
START_ASSERT_SAME_COMPARTMENT();
c.check(t1);
c.check(t2);
c.check(t3);
c.check(t4);
#endif
}
template <class T1, class T2, class T3, class T4, class T5> inline void
assertSameCompartment(ThreadSafeContext *cx,
const T1 &t1, const T2 &t2, const T3 &t3, const T4 &t4, const T5 &t5)
{
#ifdef JS_CRASH_DIAGNOSTICS
START_ASSERT_SAME_COMPARTMENT();
c.check(t1);
c.check(t2);
c.check(t3);
c.check(t4);
c.check(t5);
#endif
}
#undef START_ASSERT_SAME_COMPARTMENT
STATIC_PRECONDITION_ASSUME(ubound(args.argv_) >= argc)
MOZ_ALWAYS_INLINE bool
CallJSNative(JSContext *cx, Native native, const CallArgs &args)
{
JS_CHECK_RECURSION(cx, return false);
#ifdef DEBUG
bool alreadyThrowing = cx->isExceptionPending();
#endif
assertSameCompartment(cx, args);
bool ok = native(cx, args.length(), args.base());
if (ok) {
assertSameCompartment(cx, args.rval());
MOZ_ASSERT_IF(!alreadyThrowing, !cx->isExceptionPending());
}
return ok;
}
STATIC_PRECONDITION_ASSUME(ubound(args.argv_) >= argc)
MOZ_ALWAYS_INLINE bool
CallNativeImpl(JSContext *cx, NativeImpl impl, const CallArgs &args)
{
#ifdef DEBUG
bool alreadyThrowing = cx->isExceptionPending();
#endif
assertSameCompartment(cx, args);
bool ok = impl(cx, args);
if (ok) {
assertSameCompartment(cx, args.rval());
MOZ_ASSERT_IF(!alreadyThrowing, !cx->isExceptionPending());
}
return ok;
}
STATIC_PRECONDITION(ubound(args.argv_) >= argc)
MOZ_ALWAYS_INLINE bool
CallJSNativeConstructor(JSContext *cx, Native native, const CallArgs &args)
{
#ifdef DEBUG
RootedObject callee(cx, &args.callee());
#endif
MOZ_ASSERT(args.thisv().isMagic());
if (!CallJSNative(cx, native, args))
return false;
/*
* Native constructors must return non-primitive values on success.
* Although it is legal, if a constructor returns the callee, there is a
* 99.9999% chance it is a bug. If any valid code actually wants the
* constructor to return the callee, the assertion can be removed or
* (another) conjunct can be added to the antecedent.
*
* Exceptions:
*
* - Proxies are exceptions to both rules: they can return primitives and
* they allow content to return the callee.
*
* - CallOrConstructBoundFunction is an exception as well because we might
* have used bind on a proxy function.
*
* - new Iterator(x) is user-hookable; it returns x.__iterator__() which
* could be any object.
*
* - (new Object(Object)) returns the callee.
*/
MOZ_ASSERT_IF(native != js::proxy_Construct &&
native != js::CallOrConstructBoundFunction &&
native != js::IteratorConstructor &&
(!callee->is<JSFunction>() || callee->as<JSFunction>().native() != obj_construct),
args.rval().isObject() && callee != &args.rval().toObject());
return true;
}
MOZ_ALWAYS_INLINE bool
CallJSPropertyOp(JSContext *cx, PropertyOp op, HandleObject receiver, HandleId id, MutableHandleValue vp)
{
JS_CHECK_RECURSION(cx, return false);
assertSameCompartment(cx, receiver, id, vp);
bool ok = op(cx, receiver, id, vp);
if (ok)
assertSameCompartment(cx, vp);
return ok;
}
MOZ_ALWAYS_INLINE bool
CallJSPropertyOpSetter(JSContext *cx, StrictPropertyOp op, HandleObject obj, HandleId id,
bool strict, MutableHandleValue vp)
{
JS_CHECK_RECURSION(cx, return false);
assertSameCompartment(cx, obj, id, vp);
return op(cx, obj, id, strict, vp);
}
static inline bool
CallJSDeletePropertyOp(JSContext *cx, JSDeletePropertyOp op, HandleObject receiver, HandleId id,
bool *succeeded)
{
JS_CHECK_RECURSION(cx, return false);
assertSameCompartment(cx, receiver, id);
return op(cx, receiver, id, succeeded);
}
inline bool
CallSetter(JSContext *cx, HandleObject obj, HandleId id, StrictPropertyOp op, unsigned attrs,
bool strict, MutableHandleValue vp)
{
if (attrs & JSPROP_SETTER) {
RootedValue opv(cx, CastAsObjectJsval(op));
return InvokeGetterOrSetter(cx, obj, opv, 1, vp.address(), vp);
}
if (attrs & JSPROP_GETTER)
return js_ReportGetterOnlyAssignment(cx, strict);
return CallJSPropertyOpSetter(cx, op, obj, id, strict, vp);
}
inline uintptr_t
GetNativeStackLimit(ThreadSafeContext *cx)
{
StackKind kind;
if (cx->isJSContext()) {
kind = cx->asJSContext()->runningWithTrustedPrincipals()
? StackForTrustedScript : StackForUntrustedScript;
} else {
// For other threads, we just use the trusted stack depth, since it's
// unlikely that we'll be mixing trusted and untrusted code together.
kind = StackForTrustedScript;
}
return cx->perThreadData->nativeStackLimit[kind];
}
inline LifoAlloc &
ExclusiveContext::typeLifoAlloc()
{
return zone()->types.typeLifoAlloc;
}
} /* namespace js */
inline void
JSContext::setPendingException(js::Value v)
{
MOZ_ASSERT(!IsPoisonedValue(v));
// overRecursed_ is set after the fact by js_ReportOverRecursed.
this->overRecursed_ = false;
this->throwing = true;
this->unwrappedException_ = v;
// We don't use assertSameCompartment here to allow
// js::SetPendingExceptionCrossContext to work.
MOZ_ASSERT_IF(v.isObject(), v.toObject().compartment() == compartment());
}
inline bool
JSContext::runningWithTrustedPrincipals() const
{
return !compartment() || compartment()->principals == runtime()->trustedPrincipals();
}
inline void
js::ExclusiveContext::enterCompartment(JSCompartment *c)
{
enterCompartmentDepth_++;
c->enter();
setCompartment(c);
}
inline void
js::ExclusiveContext::enterNullCompartment()
{
enterCompartmentDepth_++;
setCompartment(nullptr);
}
inline void
js::ExclusiveContext::leaveCompartment(JSCompartment *oldCompartment)
{
MOZ_ASSERT(hasEnteredCompartment());
enterCompartmentDepth_--;
// Only call leave() after we've setCompartment()-ed away from the current
// compartment.
JSCompartment *startingCompartment = compartment_;
setCompartment(oldCompartment);
if (startingCompartment)
startingCompartment->leave();
}
inline void
js::ExclusiveContext::setCompartment(JSCompartment *comp)
{
// ExclusiveContexts can only be in the atoms zone or in exclusive zones.
MOZ_ASSERT_IF(!isJSContext() && !runtime_->isAtomsCompartment(comp),
comp->zone()->usedByExclusiveThread);
// Normal JSContexts cannot enter exclusive zones.
MOZ_ASSERT_IF(isJSContext() && comp,
!comp->zone()->usedByExclusiveThread);
// Only one thread can be in the atoms compartment at a time.
MOZ_ASSERT_IF(runtime_->isAtomsCompartment(comp),
runtime_->currentThreadHasExclusiveAccess());
// Make sure that the atoms compartment has its own zone.
MOZ_ASSERT_IF(comp && !runtime_->isAtomsCompartment(comp),
!runtime_->isAtomsZone(comp->zone()));
// Both the current and the new compartment should be properly marked as
// entered at this point.
MOZ_ASSERT_IF(compartment_, compartment_->hasBeenEntered());
MOZ_ASSERT_IF(comp, comp->hasBeenEntered());
compartment_ = comp;
zone_ = comp ? comp->zone() : nullptr;
allocator_ = zone_ ? &zone_->allocator : nullptr;
}
inline JSScript *
JSContext::currentScript(jsbytecode **ppc,
MaybeAllowCrossCompartment allowCrossCompartment) const
{
if (ppc)
*ppc = nullptr;
js::Activation *act = mainThread().activation();
while (act && (act->cx() != this || (act->isJit() && !act->asJit()->isActive())))
act = act->prev();
if (!act)
return nullptr;
MOZ_ASSERT(act->cx() == this);
if (act->isJit()) {
JSScript *script = nullptr;
js::jit::GetPcScript(const_cast<JSContext *>(this), &script, ppc);
if (!allowCrossCompartment && script->compartment() != compartment())
return nullptr;
return script;
}
if (act->isAsmJS())
return nullptr;
MOZ_ASSERT(act->isInterpreter());
js::InterpreterFrame *fp = act->asInterpreter()->current();
MOZ_ASSERT(!fp->runningInJit());
JSScript *script = fp->script();
if (!allowCrossCompartment && script->compartment() != compartment())
return nullptr;
if (ppc) {
*ppc = act->asInterpreter()->regs().pc;
MOZ_ASSERT(script->containsPC(*ppc));
}
return script;
}
template <JSThreadSafeNative threadSafeNative>
inline bool
JSNativeThreadSafeWrapper(JSContext *cx, unsigned argc, JS::Value *vp)
{
return threadSafeNative(cx, argc, vp);
}
template <JSThreadSafeNative threadSafeNative>
inline bool
JSParallelNativeThreadSafeWrapper(js::ForkJoinContext *cx, unsigned argc, JS::Value *vp)
{
return threadSafeNative(cx, argc, vp);
}
/* static */ inline JSContext *
js::ExecutionModeTraits<js::SequentialExecution>::toContextType(ExclusiveContext *cx)
{
return cx->asJSContext();
}
#endif /* jscntxtinlines_h */