/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sw=4 et tw=78:
*
* 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 xpcpublic_h
#define xpcpublic_h
#include "jsapi.h"
#include "js/MemoryMetrics.h"
#include "jsclass.h"
#include "jsfriendapi.h"
#include "jspubtd.h"
#include "jsproxy.h"
#include "js/HeapAPI.h"
#include "js/GCAPI.h"
#include "nsISupports.h"
#include "nsIPrincipal.h"
#include "nsWrapperCache.h"
#include "nsStringGlue.h"
#include "nsTArray.h"
#include "mozilla/dom/DOMJSClass.h"
#include "nsMathUtils.h"
#include "nsStringBuffer.h"
#include "mozilla/dom/BindingDeclarations.h"
class nsIPrincipal;
class nsIXPConnectWrappedJS;
class nsScriptNameSpaceManager;
#ifndef BAD_TLS_INDEX
#define BAD_TLS_INDEX ((uint32_t) -1)
#endif
namespace xpc {
JSObject *
TransplantObject(JSContext *cx, JSObject *origobj, JSObject *target);
JSObject *
TransplantObjectWithWrapper(JSContext *cx,
JSObject *origobj, JSObject *origwrapper,
JSObject *targetobj, JSObject *targetwrapper);
// Return a raw XBL scope object corresponding to contentScope, which must
// be an object whose global is a DOM window.
//
// The return value is not wrapped into cx->compartment, so be sure to enter
// its compartment before doing anything meaningful.
JSObject *
GetXBLScope(JSContext *cx, JSObject *contentScope);
// Returns whether XBL scopes have been explicitly disabled for code running
// in this compartment. See the comment around mAllowXBLScope.
bool
AllowXBLScope(JSCompartment *c);
} /* namespace xpc */
#define XPCONNECT_GLOBAL_FLAGS \
JSCLASS_DOM_GLOBAL | JSCLASS_HAS_PRIVATE | \
JSCLASS_PRIVATE_IS_NSISUPPORTS | JSCLASS_IMPLEMENTS_BARRIERS | \
JSCLASS_GLOBAL_FLAGS_WITH_SLOTS(2)
void
TraceXPCGlobal(JSTracer *trc, JSObject *obj);
// XXX These should be moved into XPCJSRuntime!
NS_EXPORT_(bool)
xpc_LocalizeRuntime(JSRuntime *rt);
NS_EXPORT_(void)
xpc_DelocalizeRuntime(JSRuntime *rt);
nsresult
xpc_MorphSlimWrapper(JSContext *cx, nsISupports *tomorph);
static inline bool IS_WRAPPER_CLASS(js::Class* clazz)
{
return clazz->ext.isWrappedNative;
}
// If IS_WRAPPER_CLASS for the JSClass of an object is true, the object can be
// a slim wrapper, holding a native in its private slot, or a wrappednative
// wrapper, holding the XPCWrappedNative in its private slot. A slim wrapper
// also holds a pointer to its XPCWrappedNativeProto in a reserved slot, we can
// check that slot for a private value (i.e. a double) to distinguish between
// the two. This allows us to store a JSObject in that slot for non-slim wrappers
// while still being able to distinguish the two cases.
// NB: This slot isn't actually reserved for us on globals, because SpiderMonkey
// uses the first N slots on globals internally. The fact that we use it for
// wrapped global objects is totally broken. But due to a happy coincidence, the
// JS engine never uses that slot. This still needs fixing though. See bug 760095.
#define WRAPPER_MULTISLOT 0
static inline bool IS_WN_WRAPPER_OBJECT(JSObject *obj)
{
MOZ_ASSERT(IS_WRAPPER_CLASS(js::GetObjectClass(obj)));
return !js::GetReservedSlot(obj, WRAPPER_MULTISLOT).isDouble();
}
static inline bool IS_SLIM_WRAPPER_OBJECT(JSObject *obj)
{
return !IS_WN_WRAPPER_OBJECT(obj);
}
// Use these functions if IS_WRAPPER_CLASS(GetObjectClass(obj)) might be false.
// Avoid calling them if IS_WRAPPER_CLASS(GetObjectClass(obj)) can only be
// true, as we'd do a redundant call to IS_WRAPPER_CLASS.
static inline bool IS_WN_WRAPPER(JSObject *obj)
{
return IS_WRAPPER_CLASS(js::GetObjectClass(obj)) && IS_WN_WRAPPER_OBJECT(obj);
}
static inline bool IS_SLIM_WRAPPER(JSObject *obj)
{
return IS_WRAPPER_CLASS(js::GetObjectClass(obj)) && IS_SLIM_WRAPPER_OBJECT(obj);
}
extern bool
xpc_OkToHandOutWrapper(nsWrapperCache *cache);
inline JSObject*
xpc_FastGetCachedWrapper(nsWrapperCache *cache, JSObject *scope, jsval *vp)
{
if (cache) {
JSObject* wrapper = cache->GetWrapper();
NS_ASSERTION(!wrapper ||
!cache->IsDOMBinding() ||
!IS_SLIM_WRAPPER(wrapper),
"Should never have a slim wrapper when IsDOMBinding()");
if (wrapper &&
js::GetObjectCompartment(wrapper) == js::GetObjectCompartment(scope) &&
(cache->IsDOMBinding() ? !cache->HasSystemOnlyWrapper() :
(IS_SLIM_WRAPPER(wrapper) || xpc_OkToHandOutWrapper(cache)))) {
*vp = OBJECT_TO_JSVAL(wrapper);
return wrapper;
}
}
return nullptr;
}
// The JS GC marks objects gray that are held alive directly or
// indirectly by an XPConnect root. The cycle collector explores only
// this subset of the JS heap.
inline JSBool
xpc_IsGrayGCThing(void *thing)
{
return JS::GCThingIsMarkedGray(thing);
}
// The cycle collector only cares about some kinds of GCthings that are
// reachable from an XPConnect root. Implemented in nsXPConnect.cpp.
extern JSBool
xpc_GCThingIsGrayCCThing(void *thing);
// Unmark gray for known-nonnull cases
MOZ_ALWAYS_INLINE void
xpc_UnmarkNonNullGrayObject(JSObject *obj)
{
JS::ExposeGCThingToActiveJS(obj, JSTRACE_OBJECT);
}
// Remove the gray color from the given JSObject and any other objects that can
// be reached through it.
MOZ_ALWAYS_INLINE JSObject *
xpc_UnmarkGrayObject(JSObject *obj)
{
if (obj)
xpc_UnmarkNonNullGrayObject(obj);
return obj;
}
inline JSScript *
xpc_UnmarkGrayScript(JSScript *script)
{
if (script)
JS::ExposeGCThingToActiveJS(script, JSTRACE_SCRIPT);
return script;
}
inline JSContext *
xpc_UnmarkGrayContext(JSContext *cx)
{
if (cx) {
JSObject *global = JS_GetGlobalObject(cx);
xpc_UnmarkGrayObject(global);
if (global && JS_IsInRequest(JS_GetRuntime(cx))) {
JSObject *scope = JS_GetGlobalForScopeChain(cx);
if (scope != global)
xpc_UnmarkGrayObject(scope);
}
}
return cx;
}
#ifdef __cplusplus
class XPCAutoRequest : public JSAutoRequest {
public:
XPCAutoRequest(JSContext *cx) : JSAutoRequest(cx) {
xpc_UnmarkGrayContext(cx);
}
};
#endif
// If aVariant is an XPCVariant, this marks the object to be in aGeneration.
// This also unmarks the gray JSObject.
extern void
xpc_MarkInCCGeneration(nsISupports* aVariant, uint32_t aGeneration);
// If aWrappedJS is a JS wrapper, unmark its JSObject.
extern void
xpc_TryUnmarkWrappedGrayObject(nsISupports* aWrappedJS);
extern void
xpc_UnmarkSkippableJSHolders();
// No JS can be on the stack when this is called. Probably only useful from
// xpcshell.
NS_EXPORT_(void)
xpc_ActivateDebugMode();
class nsIMemoryMultiReporterCallback;
// readable string conversions, static methods and members only
class XPCStringConvert
{
public:
// If the string shares the readable's buffer, that buffer will
// get assigned to *sharedBuffer. Otherwise null will be
// assigned.
static jsval ReadableToJSVal(JSContext *cx, const nsAString &readable,
nsStringBuffer** sharedBuffer);
// Convert the given stringbuffer/length pair to a jsval
static MOZ_ALWAYS_INLINE bool
StringBufferToJSVal(JSContext* cx, nsStringBuffer* buf, uint32_t length,
JS::Value* rval, bool* sharedBuffer)
{
if (buf == sCachedBuffer &&
js::GetGCThingCompartment(sCachedString) == js::GetContextCompartment(cx)) {
*rval = JS::StringValue(sCachedString);
*sharedBuffer = false;
return true;
}
JSString *str = JS_NewExternalString(cx,
static_cast<jschar*>(buf->Data()),
length, &sDOMStringFinalizer);
if (!str) {
return false;
}
*rval = JS::StringValue(str);
sCachedString = str;
sCachedBuffer = buf;
*sharedBuffer = true;
return true;
}
static void ClearCache();
private:
static nsStringBuffer* sCachedBuffer;
static JSString* sCachedString;
static const JSStringFinalizer sDOMStringFinalizer;
static void FinalizeDOMString(const JSStringFinalizer *fin, jschar *chars);
XPCStringConvert(); // not implemented
};
namespace xpc {
bool DeferredRelease(nsISupports *obj);
// If these functions return false, then an exception will be set on cx.
NS_EXPORT_(bool) Base64Encode(JSContext *cx, JS::Value val, JS::Value *out);
NS_EXPORT_(bool) Base64Decode(JSContext *cx, JS::Value val, JS::Value *out);
/**
* Convert an nsString to jsval, returning true on success.
* Note, the ownership of the string buffer may be moved from str to rval.
* If that happens, str will point to an empty string after this call.
*/
bool NonVoidStringToJsval(JSContext *cx, nsAString &str, JS::Value *rval);
inline bool StringToJsval(JSContext *cx, nsAString &str, JS::Value *rval)
{
// From the T_DOMSTRING case in XPCConvert::NativeData2JS.
if (str.IsVoid()) {
*rval = JSVAL_NULL;
return true;
}
return NonVoidStringToJsval(cx, str, rval);
}
/**
* As above, but for mozilla::dom::DOMString.
*/
MOZ_ALWAYS_INLINE
bool NonVoidStringToJsval(JSContext* cx, mozilla::dom::DOMString& str,
JS::Value *rval)
{
if (!str.HasStringBuffer()) {
// It's an actual XPCOM string
return NonVoidStringToJsval(cx, str.AsAString(), rval);
}
uint32_t length = str.StringBufferLength();
if (length == 0) {
*rval = JS_GetEmptyStringValue(cx);
return true;
}
nsStringBuffer* buf = str.StringBuffer();
bool shared;
if (!XPCStringConvert::StringBufferToJSVal(cx, buf, length, rval,
&shared)) {
return false;
}
if (shared) {
// JS now needs to hold a reference to the buffer
buf->AddRef();
}
return true;
}
MOZ_ALWAYS_INLINE
bool StringToJsval(JSContext* cx, mozilla::dom::DOMString& str,
JS::Value *rval)
{
if (str.IsNull()) {
*rval = JS::NullValue();
return true;
}
return NonVoidStringToJsval(cx, str, rval);
}
nsIPrincipal *GetCompartmentPrincipal(JSCompartment *compartment);
bool IsXBLScope(JSCompartment *compartment);
void DumpJSHeap(FILE* file);
void SetLocationForGlobal(JSObject *global, const nsACString& location);
void SetLocationForGlobal(JSObject *global, nsIURI *locationURI);
/**
* Define quick stubs on the given object, @a proto.
*
* @param cx
* A context. Requires request.
* @param proto
* The (newly created) prototype object for a DOM class. The JS half
* of an XPCWrappedNativeProto.
* @param flags
* Property flags for the quick stub properties--should be either
* JSPROP_ENUMERATE or 0.
* @param interfaceCount
* The number of interfaces the class implements.
* @param interfaceArray
* The interfaces the class implements; interfaceArray and
* interfaceCount are like what nsIClassInfo.getInterfaces returns.
*/
bool
DOM_DefineQuickStubs(JSContext *cx, JSObject *proto, uint32_t flags,
uint32_t interfaceCount, const nsIID **interfaceArray);
// This reports all the stats in |rtStats| that belong in the "explicit" tree,
// (which isn't all of them).
nsresult
ReportJSRuntimeExplicitTreeStats(const JS::RuntimeStats &rtStats,
const nsACString &rtPath,
nsIMemoryMultiReporterCallback *cb,
nsISupports *closure, size_t *rtTotal = NULL);
/**
* Given an arbitrary object, Unwrap will return the wrapped object if the
* passed-in object is a wrapper that Unwrap knows about *and* the
* currently running code has permission to access both the wrapper and
* wrapped object.
*
* Since this is meant to be called from functions like
* XPCWrappedNative::GetWrappedNativeOfJSObject, it does not set an
* exception on |cx|.
*/
JSObject *
Unwrap(JSContext *cx, JSObject *wrapper, bool stopAtOuter = true);
/**
* Throws an exception on cx and returns false.
*/
bool
Throw(JSContext *cx, nsresult rv);
} // namespace xpc
nsCycleCollectionParticipant *
xpc_JSCompartmentParticipant();
namespace mozilla {
namespace dom {
extern int HandlerFamily;
inline void* ProxyFamily() { return &HandlerFamily; }
inline bool IsDOMProxy(JSObject *obj, const js::Class* clasp)
{
MOZ_ASSERT(js::GetObjectClass(obj) == clasp);
return (js::IsObjectProxyClass(clasp) || js::IsFunctionProxyClass(clasp)) &&
js::GetProxyHandler(obj)->family() == ProxyFamily();
}
inline bool IsDOMProxy(JSObject *obj)
{
return IsDOMProxy(obj, js::GetObjectClass(obj));
}
typedef JSObject*
(*DefineInterface)(JSContext *cx, JSObject *global, bool *enabled);
typedef bool
(*PrefEnabled)();
extern bool
DefineStaticJSVals(JSContext *cx);
void
Register(nsScriptNameSpaceManager* aNameSpaceManager);
} // namespace dom
} // namespace mozilla
#endif