https://github.com/mozilla/gecko-dev
Tip revision: cb988159e8d6ef4e5ed42c329ad7d04e49741c41 authored by B2G Bumper Bot on 28 April 2014, 13:11:32 UTC
Bumping manifests a=b2g-bump
Bumping manifests a=b2g-bump
Tip revision: cb98815
xpcpublic.h
/* -*- 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 "jsproxy.h"
#include "js/HeapAPI.h"
#include "js/GCAPI.h"
#include "nsISupports.h"
#include "nsIURI.h"
#include "nsIPrincipal.h"
#include "nsWrapperCache.h"
#include "nsStringGlue.h"
#include "nsTArray.h"
#include "mozilla/dom/JSSlots.h"
#include "nsMathUtils.h"
#include "nsStringBuffer.h"
#include "mozilla/dom/BindingDeclarations.h"
class nsIPrincipal;
class nsScriptNameSpaceManager;
class nsIGlobalObject;
class nsIMemoryReporterCallback;
#ifndef BAD_TLS_INDEX
#define BAD_TLS_INDEX ((uint32_t) -1)
#endif
namespace xpc {
class Scriptability {
public:
Scriptability(JSCompartment *c);
bool Allowed();
bool IsImmuneToScriptPolicy();
void Block();
void Unblock();
void SetDocShellAllowsScript(bool aAllowed);
static Scriptability& Get(JSObject *aScope);
private:
// Whenever a consumer wishes to prevent script from running on a global,
// it increments this value with a call to Block(). When it wishes to
// re-enable it (if ever), it decrements this value with a call to Unblock().
// Script may not run if this value is non-zero.
uint32_t mScriptBlocks;
// Whether the docshell allows javascript in this scope. If this scope
// doesn't have a docshell, this value is always true.
bool mDocShellAllowsScript;
// Whether this scope is immune to user-defined or addon-defined script
// policy.
bool mImmuneToScriptPolicy;
// Whether the new-style domain policy when this compartment was created
// forbids script execution.
bool mScriptBlockedByPolicy;
};
JSObject *
TransplantObject(JSContext *cx, JS::HandleObject origobj, JS::HandleObject target);
// 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.
//
// Also note that XBL scopes are lazily created, so the return-value should be
// null-checked unless the caller can ensure that the scope must already
// exist.
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);
// Returns whether we will use an XBL scope for this compartment. This is
// semantically equivalent to comparing global != GetXBLScope(global), but it
// does not have the side-effect of eagerly creating the XBL scope if it does
// not already exist.
bool
UseXBLScope(JSCompartment *c);
bool
IsSandboxPrototypeProxy(JSObject *obj);
bool
IsReflector(JSObject *obj);
bool
IsXrayWrapper(JSObject *obj);
} /* namespace xpc */
namespace JS {
struct RuntimeStats;
}
#define XPCONNECT_GLOBAL_FLAGS_WITH_EXTRA_SLOTS(n) \
JSCLASS_DOM_GLOBAL | JSCLASS_HAS_PRIVATE | \
JSCLASS_PRIVATE_IS_NSISUPPORTS | JSCLASS_IMPLEMENTS_BARRIERS | \
JSCLASS_GLOBAL_FLAGS_WITH_SLOTS(DOM_GLOBAL_SLOTS + n)
#define XPCONNECT_GLOBAL_EXTRA_SLOT_OFFSET (JSCLASS_GLOBAL_SLOT_COUNT + DOM_GLOBAL_SLOTS)
#define XPCONNECT_GLOBAL_FLAGS XPCONNECT_GLOBAL_FLAGS_WITH_EXTRA_SLOTS(0)
extern bool
xpc_OkToHandOutWrapper(nsWrapperCache *cache);
inline JSObject*
xpc_FastGetCachedWrapper(nsWrapperCache *cache, JSObject *scope, JS::MutableHandleValue vp)
{
if (cache) {
JSObject* wrapper = cache->GetWrapper();
if (wrapper &&
js::GetObjectCompartment(wrapper) == js::GetObjectCompartment(scope) &&
(cache->IsDOMBinding() ? !cache->HasSystemOnlyWrapper() :
xpc_OkToHandOutWrapper(cache))) {
vp.setObject(*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 bool
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 bool
xpc_GCThingIsGrayCCThing(void *thing);
inline JSScript *
xpc_UnmarkGrayScript(JSScript *script)
{
if (script)
JS::ExposeGCThingToActiveJS(script, JSTRACE_SCRIPT);
return script;
}
// 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();
// readable string conversions, static methods and members only
class XPCStringConvert
{
// One-slot cache, because it turns out it's common for web pages to
// get the same string a few times in a row. We get about a 40% cache
// hit rate on this cache last it was measured. We'd get about 70%
// hit rate with a hashtable with removal on finalization, but that
// would take a lot more machinery.
struct ZoneStringCache
{
nsStringBuffer* mBuffer;
JSString* mString;
};
public:
// If the string shares the readable's buffer, that buffer will
// get assigned to *sharedBuffer. Otherwise null will be
// assigned.
static bool ReadableToJSVal(JSContext *cx, const nsAString &readable,
nsStringBuffer** sharedBuffer,
JS::MutableHandleValue vp);
// Convert the given stringbuffer/length pair to a jsval
static MOZ_ALWAYS_INLINE bool
StringBufferToJSVal(JSContext* cx, nsStringBuffer* buf, uint32_t length,
JS::MutableHandleValue rval, bool* sharedBuffer)
{
JS::Zone *zone = js::GetContextZone(cx);
ZoneStringCache *cache = static_cast<ZoneStringCache*>(JS_GetZoneUserData(zone));
if (cache && buf == cache->mBuffer) {
MOZ_ASSERT(JS::GetGCThingZone(cache->mString) == zone);
JS::MarkStringAsLive(zone, cache->mString);
rval.setString(cache->mString);
*sharedBuffer = false;
return true;
}
JSString *str = JS_NewExternalString(cx,
static_cast<jschar*>(buf->Data()),
length, &sDOMStringFinalizer);
if (!str) {
return false;
}
rval.setString(str);
if (!cache) {
cache = new ZoneStringCache();
JS_SetZoneUserData(zone, cache);
}
cache->mBuffer = buf;
cache->mString = str;
*sharedBuffer = true;
return true;
}
static void FreeZoneCache(JS::Zone *zone);
static void ClearZoneCache(JS::Zone *zone);
private:
static const JSStringFinalizer sDOMStringFinalizer;
static void FinalizeDOMString(const JSStringFinalizer *fin, jschar *chars);
XPCStringConvert(); // not implemented
};
namespace xpc {
// 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::MutableHandleValue rval);
inline bool StringToJsval(JSContext *cx, nsAString &str, JS::MutableHandleValue rval)
{
// From the T_DOMSTRING case in XPCConvert::NativeData2JS.
if (str.IsVoid()) {
rval.setNull();
return true;
}
return NonVoidStringToJsval(cx, str, rval);
}
inline bool
NonVoidStringToJsval(JSContext* cx, const nsAString& str, JS::MutableHandleValue rval)
{
nsString mutableCopy(str);
return NonVoidStringToJsval(cx, mutableCopy, rval);
}
inline bool
StringToJsval(JSContext* cx, const nsAString& str, JS::MutableHandleValue rval)
{
nsString mutableCopy(str);
return StringToJsval(cx, mutableCopy, rval);
}
/**
* As above, but for mozilla::dom::DOMString.
*/
MOZ_ALWAYS_INLINE
bool NonVoidStringToJsval(JSContext* cx, mozilla::dom::DOMString& str,
JS::MutableHandleValue 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.set(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::MutableHandleValue rval)
{
if (str.IsNull()) {
rval.setNull();
return true;
}
return NonVoidStringToJsval(cx, str, rval);
}
nsIPrincipal *GetCompartmentPrincipal(JSCompartment *compartment);
bool IsXBLScope(JSCompartment *compartment);
bool IsInXBLScope(JSObject *obj);
void SetLocationForGlobal(JSObject *global, const nsACString& location);
void SetLocationForGlobal(JSObject *global, nsIURI *locationURI);
// ReportJSRuntimeExplicitTreeStats will expect this in the |extra| member
// of JS::ZoneStats.
class ZoneStatsExtras {
public:
ZoneStatsExtras()
{}
nsAutoCString pathPrefix;
private:
ZoneStatsExtras(const ZoneStatsExtras &other) MOZ_DELETE;
ZoneStatsExtras& operator=(const ZoneStatsExtras &other) MOZ_DELETE;
};
// ReportJSRuntimeExplicitTreeStats will expect this in the |extra| member
// of JS::CompartmentStats.
class CompartmentStatsExtras {
public:
CompartmentStatsExtras()
{}
nsAutoCString jsPathPrefix;
nsAutoCString domPathPrefix;
nsCOMPtr<nsIURI> location;
private:
CompartmentStatsExtras(const CompartmentStatsExtras &other) MOZ_DELETE;
CompartmentStatsExtras& operator=(const CompartmentStatsExtras &other) MOZ_DELETE;
};
// This reports all the stats in |rtStats| that belong in the "explicit" tree,
// (which isn't all of them).
// @see ZoneStatsExtras
// @see CompartmentStatsExtras
nsresult
ReportJSRuntimeExplicitTreeStats(const JS::RuntimeStats &rtStats,
const nsACString &rtPath,
nsIMemoryReporterCallback *cb,
nsISupports *closure, size_t *rtTotal = nullptr);
/**
* Throws an exception on cx and returns false.
*/
bool
Throw(JSContext *cx, nsresult rv);
/**
* Every global should hold a native that implements the nsIGlobalObject interface.
*/
nsIGlobalObject *
GetNativeForGlobal(JSObject *global);
/**
* In some cases a native object does not really belong to any compartment (XBL,
* document created from by XHR of a worker, etc.). But when for some reason we
* have to wrap these natives (because of an event for example) instead of just
* wrapping them into some random compartment we find on the context stack (like
* we did previously) a default compartment is used. This function returns that
* compartment's global. It is a singleton on the runtime.
* If you find yourself wanting to use this compartment, you're probably doing
* something wrong. Callers MUST consult with the XPConnect module owner before
* using this compartment. If you don't, bholley will hunt you down.
*/
JSObject *
GetJunkScope();
/**
* Returns the native global of the junk scope. See comment of GetJunkScope
* about the conditions of using it.
*/
nsIGlobalObject *
GetJunkScopeGlobal();
/**
* Shared compilation scope for XUL prototype documents and XBL
* precompilation. This compartment has a null principal. No code may run, and
* it is invisible to the debugger.
*/
JSObject *
GetCompilationScope();
/**
* If |aObj| has a window for a global, returns the associated nsGlobalWindow.
* Otherwise, returns null.
*/
nsGlobalWindow*
WindowGlobalOrNull(JSObject *aObj);
// Error reporter used when there is no associated DOM window on to which to
// report errors and warnings.
void
SystemErrorReporter(JSContext *cx, const char *message, JSErrorReport *rep);
// We have a separate version that's exported with external linkage for use by
// xpcshell, since external linkage on windows changes the signature to make it
// incompatible with the JSErrorReporter type, causing JS_SetErrorReporter calls
// to fail to compile.
NS_EXPORT_(void)
SystemErrorReporterExternal(JSContext *cx, const char *message,
JSErrorReport *rep);
NS_EXPORT_(void)
SimulateActivityCallback(bool aActive);
void
RecordAdoptedNode(JSCompartment *c);
void
RecordDonatedNode(JSCompartment *c);
// This function may be used off-main-thread, in which case it is benignly
// racey.
uint32_t
ShouldDiscardSystemSource();
void
SetDiscardSystemSource(uint32_t discard);
} // namespace xpc
namespace mozilla {
namespace dom {
typedef JSObject*
(*DefineInterface)(JSContext *cx, JS::Handle<JSObject*> global,
JS::Handle<jsid> id, bool defineOnGlobal);
typedef JSObject*
(*ConstructNavigatorProperty)(JSContext *cx, JS::Handle<JSObject*> naviObj);
// Check whether a constructor should be enabled for the given object.
// Note that the object should NOT be an Xray, since Xrays will end up
// defining constructors on the underlying object.
// This is a typedef for the function type itself, not the function
// pointer, so it's more obvious that pointers to a ConstructorEnabled
// can be null.
typedef bool
(ConstructorEnabled)(JSContext* cx, JS::Handle<JSObject*> obj);
void
Register(nsScriptNameSpaceManager* aNameSpaceManager);
/**
* A test for whether WebIDL methods that should only be visible to
* chrome or XBL scopes should be exposed.
*/
bool IsChromeOrXBL(JSContext* cx, JSObject* /* unused */);
} // namespace dom
} // namespace mozilla
#endif