1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/js/xpconnect/src/xpcpublic.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,521 @@
1.4 +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
1.5 +/* vim: set ts=8 sts=4 et sw=4 tw=99: */
1.6 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +#ifndef xpcpublic_h
1.11 +#define xpcpublic_h
1.12 +
1.13 +#include "jsapi.h"
1.14 +#include "jsproxy.h"
1.15 +#include "js/HeapAPI.h"
1.16 +#include "js/GCAPI.h"
1.17 +
1.18 +#include "nsISupports.h"
1.19 +#include "nsIURI.h"
1.20 +#include "nsIPrincipal.h"
1.21 +#include "nsWrapperCache.h"
1.22 +#include "nsStringGlue.h"
1.23 +#include "nsTArray.h"
1.24 +#include "mozilla/dom/JSSlots.h"
1.25 +#include "nsMathUtils.h"
1.26 +#include "nsStringBuffer.h"
1.27 +#include "mozilla/dom/BindingDeclarations.h"
1.28 +
1.29 +class nsGlobalWindow;
1.30 +class nsIPrincipal;
1.31 +class nsScriptNameSpaceManager;
1.32 +class nsIGlobalObject;
1.33 +class nsIMemoryReporterCallback;
1.34 +
1.35 +#ifndef BAD_TLS_INDEX
1.36 +#define BAD_TLS_INDEX ((uint32_t) -1)
1.37 +#endif
1.38 +
1.39 +namespace xpc {
1.40 +
1.41 +class Scriptability {
1.42 +public:
1.43 + Scriptability(JSCompartment *c);
1.44 + bool Allowed();
1.45 + bool IsImmuneToScriptPolicy();
1.46 +
1.47 + void Block();
1.48 + void Unblock();
1.49 + void SetDocShellAllowsScript(bool aAllowed);
1.50 +
1.51 + static Scriptability& Get(JSObject *aScope);
1.52 +
1.53 +private:
1.54 + // Whenever a consumer wishes to prevent script from running on a global,
1.55 + // it increments this value with a call to Block(). When it wishes to
1.56 + // re-enable it (if ever), it decrements this value with a call to Unblock().
1.57 + // Script may not run if this value is non-zero.
1.58 + uint32_t mScriptBlocks;
1.59 +
1.60 + // Whether the docshell allows javascript in this scope. If this scope
1.61 + // doesn't have a docshell, this value is always true.
1.62 + bool mDocShellAllowsScript;
1.63 +
1.64 + // Whether this scope is immune to user-defined or addon-defined script
1.65 + // policy.
1.66 + bool mImmuneToScriptPolicy;
1.67 +
1.68 + // Whether the new-style domain policy when this compartment was created
1.69 + // forbids script execution.
1.70 + bool mScriptBlockedByPolicy;
1.71 +};
1.72 +
1.73 +JSObject *
1.74 +TransplantObject(JSContext *cx, JS::HandleObject origobj, JS::HandleObject target);
1.75 +
1.76 +bool IsXBLScope(JSCompartment *compartment);
1.77 +bool IsInXBLScope(JSObject *obj);
1.78 +
1.79 +// Return a raw XBL scope object corresponding to contentScope, which must
1.80 +// be an object whose global is a DOM window.
1.81 +//
1.82 +// The return value is not wrapped into cx->compartment, so be sure to enter
1.83 +// its compartment before doing anything meaningful.
1.84 +//
1.85 +// Also note that XBL scopes are lazily created, so the return-value should be
1.86 +// null-checked unless the caller can ensure that the scope must already
1.87 +// exist.
1.88 +//
1.89 +// This function asserts if |contentScope| is itself in an XBL scope to catch
1.90 +// sloppy consumers. Conversely, GetXBLScopeOrGlobal will handle objects that
1.91 +// are in XBL scope (by just returning the global).
1.92 +JSObject *
1.93 +GetXBLScope(JSContext *cx, JSObject *contentScope);
1.94 +
1.95 +inline JSObject *
1.96 +GetXBLScopeOrGlobal(JSContext *cx, JSObject *obj) {
1.97 + if (IsInXBLScope(obj))
1.98 + return js::GetGlobalForObjectCrossCompartment(obj);
1.99 + return GetXBLScope(cx, obj);
1.100 +}
1.101 +
1.102 +// Returns whether XBL scopes have been explicitly disabled for code running
1.103 +// in this compartment. See the comment around mAllowXBLScope.
1.104 +bool
1.105 +AllowXBLScope(JSCompartment *c);
1.106 +
1.107 +// Returns whether we will use an XBL scope for this compartment. This is
1.108 +// semantically equivalent to comparing global != GetXBLScope(global), but it
1.109 +// does not have the side-effect of eagerly creating the XBL scope if it does
1.110 +// not already exist.
1.111 +bool
1.112 +UseXBLScope(JSCompartment *c);
1.113 +
1.114 +bool
1.115 +IsSandboxPrototypeProxy(JSObject *obj);
1.116 +
1.117 +bool
1.118 +IsReflector(JSObject *obj);
1.119 +
1.120 +bool
1.121 +IsXrayWrapper(JSObject *obj);
1.122 +
1.123 +// If this function was created for a given XrayWrapper, returns the global of
1.124 +// the Xrayed object. Otherwise, returns the global of the function.
1.125 +//
1.126 +// To emphasize the obvious: the return value here is not necessarily same-
1.127 +// compartment with the argument.
1.128 +JSObject *
1.129 +XrayAwareCalleeGlobal(JSObject *fun);
1.130 +
1.131 +void
1.132 +TraceXPCGlobal(JSTracer *trc, JSObject *obj);
1.133 +
1.134 +} /* namespace xpc */
1.135 +
1.136 +namespace JS {
1.137 +
1.138 +struct RuntimeStats;
1.139 +
1.140 +}
1.141 +
1.142 +#define XPCONNECT_GLOBAL_FLAGS_WITH_EXTRA_SLOTS(n) \
1.143 + JSCLASS_DOM_GLOBAL | JSCLASS_HAS_PRIVATE | \
1.144 + JSCLASS_PRIVATE_IS_NSISUPPORTS | JSCLASS_IMPLEMENTS_BARRIERS | \
1.145 + JSCLASS_GLOBAL_FLAGS_WITH_SLOTS(DOM_GLOBAL_SLOTS + n)
1.146 +
1.147 +#define XPCONNECT_GLOBAL_EXTRA_SLOT_OFFSET (JSCLASS_GLOBAL_SLOT_COUNT + DOM_GLOBAL_SLOTS)
1.148 +
1.149 +#define XPCONNECT_GLOBAL_FLAGS XPCONNECT_GLOBAL_FLAGS_WITH_EXTRA_SLOTS(0)
1.150 +
1.151 +inline JSObject*
1.152 +xpc_FastGetCachedWrapper(JSContext *cx, nsWrapperCache *cache, JS::MutableHandleValue vp)
1.153 +{
1.154 + if (cache) {
1.155 + JSObject* wrapper = cache->GetWrapper();
1.156 + if (wrapper &&
1.157 + js::GetObjectCompartment(wrapper) == js::GetContextCompartment(cx))
1.158 + {
1.159 + vp.setObject(*wrapper);
1.160 + return wrapper;
1.161 + }
1.162 + }
1.163 +
1.164 + return nullptr;
1.165 +}
1.166 +
1.167 +// The JS GC marks objects gray that are held alive directly or
1.168 +// indirectly by an XPConnect root. The cycle collector explores only
1.169 +// this subset of the JS heap.
1.170 +inline bool
1.171 +xpc_IsGrayGCThing(void *thing)
1.172 +{
1.173 + return JS::GCThingIsMarkedGray(thing);
1.174 +}
1.175 +
1.176 +// The cycle collector only cares about some kinds of GCthings that are
1.177 +// reachable from an XPConnect root. Implemented in nsXPConnect.cpp.
1.178 +extern bool
1.179 +xpc_GCThingIsGrayCCThing(void *thing);
1.180 +
1.181 +inline JSScript *
1.182 +xpc_UnmarkGrayScript(JSScript *script)
1.183 +{
1.184 + if (script)
1.185 + JS::ExposeGCThingToActiveJS(script, JSTRACE_SCRIPT);
1.186 +
1.187 + return script;
1.188 +}
1.189 +
1.190 +// If aVariant is an XPCVariant, this marks the object to be in aGeneration.
1.191 +// This also unmarks the gray JSObject.
1.192 +extern void
1.193 +xpc_MarkInCCGeneration(nsISupports* aVariant, uint32_t aGeneration);
1.194 +
1.195 +// If aWrappedJS is a JS wrapper, unmark its JSObject.
1.196 +extern void
1.197 +xpc_TryUnmarkWrappedGrayObject(nsISupports* aWrappedJS);
1.198 +
1.199 +extern void
1.200 +xpc_UnmarkSkippableJSHolders();
1.201 +
1.202 +// No JS can be on the stack when this is called. Probably only useful from
1.203 +// xpcshell.
1.204 +void
1.205 +xpc_ActivateDebugMode();
1.206 +
1.207 +// readable string conversions, static methods and members only
1.208 +class XPCStringConvert
1.209 +{
1.210 + // One-slot cache, because it turns out it's common for web pages to
1.211 + // get the same string a few times in a row. We get about a 40% cache
1.212 + // hit rate on this cache last it was measured. We'd get about 70%
1.213 + // hit rate with a hashtable with removal on finalization, but that
1.214 + // would take a lot more machinery.
1.215 + struct ZoneStringCache
1.216 + {
1.217 + nsStringBuffer* mBuffer;
1.218 + JSString* mString;
1.219 + };
1.220 +
1.221 +public:
1.222 +
1.223 + // If the string shares the readable's buffer, that buffer will
1.224 + // get assigned to *sharedBuffer. Otherwise null will be
1.225 + // assigned.
1.226 + static bool ReadableToJSVal(JSContext *cx, const nsAString &readable,
1.227 + nsStringBuffer** sharedBuffer,
1.228 + JS::MutableHandleValue vp);
1.229 +
1.230 + // Convert the given stringbuffer/length pair to a jsval
1.231 + static MOZ_ALWAYS_INLINE bool
1.232 + StringBufferToJSVal(JSContext* cx, nsStringBuffer* buf, uint32_t length,
1.233 + JS::MutableHandleValue rval, bool* sharedBuffer)
1.234 + {
1.235 + JS::Zone *zone = js::GetContextZone(cx);
1.236 + ZoneStringCache *cache = static_cast<ZoneStringCache*>(JS_GetZoneUserData(zone));
1.237 + if (cache && buf == cache->mBuffer) {
1.238 + MOZ_ASSERT(JS::GetGCThingZone(cache->mString) == zone);
1.239 + JS::MarkStringAsLive(zone, cache->mString);
1.240 + rval.setString(cache->mString);
1.241 + *sharedBuffer = false;
1.242 + return true;
1.243 + }
1.244 +
1.245 + JSString *str = JS_NewExternalString(cx,
1.246 + static_cast<jschar*>(buf->Data()),
1.247 + length, &sDOMStringFinalizer);
1.248 + if (!str) {
1.249 + return false;
1.250 + }
1.251 + rval.setString(str);
1.252 + if (!cache) {
1.253 + cache = new ZoneStringCache();
1.254 + JS_SetZoneUserData(zone, cache);
1.255 + }
1.256 + cache->mBuffer = buf;
1.257 + cache->mString = str;
1.258 + *sharedBuffer = true;
1.259 + return true;
1.260 + }
1.261 +
1.262 + static void FreeZoneCache(JS::Zone *zone);
1.263 + static void ClearZoneCache(JS::Zone *zone);
1.264 +
1.265 + static MOZ_ALWAYS_INLINE bool IsLiteral(JSString *str)
1.266 + {
1.267 + return JS_IsExternalString(str) &&
1.268 + JS_GetExternalStringFinalizer(str) == &sLiteralFinalizer;
1.269 + }
1.270 +
1.271 + static MOZ_ALWAYS_INLINE bool IsDOMString(JSString *str)
1.272 + {
1.273 + return JS_IsExternalString(str) &&
1.274 + JS_GetExternalStringFinalizer(str) == &sDOMStringFinalizer;
1.275 + }
1.276 +
1.277 +private:
1.278 + static const JSStringFinalizer sLiteralFinalizer, sDOMStringFinalizer;
1.279 +
1.280 + static void FinalizeLiteral(const JSStringFinalizer *fin, jschar *chars);
1.281 +
1.282 + static void FinalizeDOMString(const JSStringFinalizer *fin, jschar *chars);
1.283 +
1.284 + XPCStringConvert(); // not implemented
1.285 +};
1.286 +
1.287 +namespace xpc {
1.288 +
1.289 +// If these functions return false, then an exception will be set on cx.
1.290 +bool Base64Encode(JSContext *cx, JS::HandleValue val, JS::MutableHandleValue out);
1.291 +bool Base64Decode(JSContext *cx, JS::HandleValue val, JS::MutableHandleValue out);
1.292 +
1.293 +/**
1.294 + * Convert an nsString to jsval, returning true on success.
1.295 + * Note, the ownership of the string buffer may be moved from str to rval.
1.296 + * If that happens, str will point to an empty string after this call.
1.297 + */
1.298 +bool NonVoidStringToJsval(JSContext *cx, nsAString &str, JS::MutableHandleValue rval);
1.299 +inline bool StringToJsval(JSContext *cx, nsAString &str, JS::MutableHandleValue rval)
1.300 +{
1.301 + // From the T_DOMSTRING case in XPCConvert::NativeData2JS.
1.302 + if (str.IsVoid()) {
1.303 + rval.setNull();
1.304 + return true;
1.305 + }
1.306 + return NonVoidStringToJsval(cx, str, rval);
1.307 +}
1.308 +
1.309 +inline bool
1.310 +NonVoidStringToJsval(JSContext* cx, const nsAString& str, JS::MutableHandleValue rval)
1.311 +{
1.312 + nsString mutableCopy(str);
1.313 + return NonVoidStringToJsval(cx, mutableCopy, rval);
1.314 +}
1.315 +
1.316 +inline bool
1.317 +StringToJsval(JSContext* cx, const nsAString& str, JS::MutableHandleValue rval)
1.318 +{
1.319 + nsString mutableCopy(str);
1.320 + return StringToJsval(cx, mutableCopy, rval);
1.321 +}
1.322 +
1.323 +/**
1.324 + * As above, but for mozilla::dom::DOMString.
1.325 + */
1.326 +MOZ_ALWAYS_INLINE
1.327 +bool NonVoidStringToJsval(JSContext* cx, mozilla::dom::DOMString& str,
1.328 + JS::MutableHandleValue rval)
1.329 +{
1.330 + if (!str.HasStringBuffer()) {
1.331 + // It's an actual XPCOM string
1.332 + return NonVoidStringToJsval(cx, str.AsAString(), rval);
1.333 + }
1.334 +
1.335 + uint32_t length = str.StringBufferLength();
1.336 + if (length == 0) {
1.337 + rval.set(JS_GetEmptyStringValue(cx));
1.338 + return true;
1.339 + }
1.340 +
1.341 + nsStringBuffer* buf = str.StringBuffer();
1.342 + bool shared;
1.343 + if (!XPCStringConvert::StringBufferToJSVal(cx, buf, length, rval,
1.344 + &shared)) {
1.345 + return false;
1.346 + }
1.347 + if (shared) {
1.348 + // JS now needs to hold a reference to the buffer
1.349 + buf->AddRef();
1.350 + }
1.351 + return true;
1.352 +}
1.353 +
1.354 +MOZ_ALWAYS_INLINE
1.355 +bool StringToJsval(JSContext* cx, mozilla::dom::DOMString& str,
1.356 + JS::MutableHandleValue rval)
1.357 +{
1.358 + if (str.IsNull()) {
1.359 + rval.setNull();
1.360 + return true;
1.361 + }
1.362 + return NonVoidStringToJsval(cx, str, rval);
1.363 +}
1.364 +
1.365 +nsIPrincipal *GetCompartmentPrincipal(JSCompartment *compartment);
1.366 +
1.367 +void SetLocationForGlobal(JSObject *global, const nsACString& location);
1.368 +void SetLocationForGlobal(JSObject *global, nsIURI *locationURI);
1.369 +
1.370 +// ReportJSRuntimeExplicitTreeStats will expect this in the |extra| member
1.371 +// of JS::ZoneStats.
1.372 +class ZoneStatsExtras {
1.373 +public:
1.374 + ZoneStatsExtras()
1.375 + {}
1.376 +
1.377 + nsAutoCString pathPrefix;
1.378 +
1.379 +private:
1.380 + ZoneStatsExtras(const ZoneStatsExtras &other) MOZ_DELETE;
1.381 + ZoneStatsExtras& operator=(const ZoneStatsExtras &other) MOZ_DELETE;
1.382 +};
1.383 +
1.384 +// ReportJSRuntimeExplicitTreeStats will expect this in the |extra| member
1.385 +// of JS::CompartmentStats.
1.386 +class CompartmentStatsExtras {
1.387 +public:
1.388 + CompartmentStatsExtras()
1.389 + {}
1.390 +
1.391 + nsAutoCString jsPathPrefix;
1.392 + nsAutoCString domPathPrefix;
1.393 + nsCOMPtr<nsIURI> location;
1.394 +
1.395 +private:
1.396 + CompartmentStatsExtras(const CompartmentStatsExtras &other) MOZ_DELETE;
1.397 + CompartmentStatsExtras& operator=(const CompartmentStatsExtras &other) MOZ_DELETE;
1.398 +};
1.399 +
1.400 +// This reports all the stats in |rtStats| that belong in the "explicit" tree,
1.401 +// (which isn't all of them).
1.402 +// @see ZoneStatsExtras
1.403 +// @see CompartmentStatsExtras
1.404 +nsresult
1.405 +ReportJSRuntimeExplicitTreeStats(const JS::RuntimeStats &rtStats,
1.406 + const nsACString &rtPath,
1.407 + nsIMemoryReporterCallback *cb,
1.408 + nsISupports *closure, size_t *rtTotal = nullptr);
1.409 +
1.410 +/**
1.411 + * Throws an exception on cx and returns false.
1.412 + */
1.413 +bool
1.414 +Throw(JSContext *cx, nsresult rv);
1.415 +
1.416 +/**
1.417 + * Every global should hold a native that implements the nsIGlobalObject interface.
1.418 + */
1.419 +nsIGlobalObject *
1.420 +GetNativeForGlobal(JSObject *global);
1.421 +
1.422 +/**
1.423 + * In some cases a native object does not really belong to any compartment (XBL,
1.424 + * document created from by XHR of a worker, etc.). But when for some reason we
1.425 + * have to wrap these natives (because of an event for example) instead of just
1.426 + * wrapping them into some random compartment we find on the context stack (like
1.427 + * we did previously) a default compartment is used. This function returns that
1.428 + * compartment's global. It is a singleton on the runtime.
1.429 + * If you find yourself wanting to use this compartment, you're probably doing
1.430 + * something wrong. Callers MUST consult with the XPConnect module owner before
1.431 + * using this compartment. If you don't, bholley will hunt you down.
1.432 + */
1.433 +JSObject *
1.434 +GetJunkScope();
1.435 +
1.436 +/**
1.437 + * Returns the native global of the junk scope. See comment of GetJunkScope
1.438 + * about the conditions of using it.
1.439 + */
1.440 +nsIGlobalObject *
1.441 +GetJunkScopeGlobal();
1.442 +
1.443 +/**
1.444 + * Shared compilation scope for XUL prototype documents and XBL
1.445 + * precompilation. This compartment has a null principal. No code may run, and
1.446 + * it is invisible to the debugger.
1.447 + */
1.448 +JSObject *
1.449 +GetCompilationScope();
1.450 +
1.451 +/**
1.452 + * If |aObj| is a window, returns the associated nsGlobalWindow.
1.453 + * Otherwise, returns null.
1.454 + */
1.455 +nsGlobalWindow*
1.456 +WindowOrNull(JSObject *aObj);
1.457 +
1.458 +/*
1.459 + * Returns the dummy global associated with the SafeJSContext. Callers MUST
1.460 + * consult with the XPConnect module owner before using this function.
1.461 + */
1.462 +JSObject *
1.463 +GetSafeJSContextGlobal();
1.464 +
1.465 +/**
1.466 + * If |aObj| has a window for a global, returns the associated nsGlobalWindow.
1.467 + * Otherwise, returns null.
1.468 + */
1.469 +nsGlobalWindow*
1.470 +WindowGlobalOrNull(JSObject *aObj);
1.471 +
1.472 +// Error reporter used when there is no associated DOM window on to which to
1.473 +// report errors and warnings.
1.474 +void
1.475 +SystemErrorReporter(JSContext *cx, const char *message, JSErrorReport *rep);
1.476 +
1.477 +void
1.478 +SimulateActivityCallback(bool aActive);
1.479 +
1.480 +void
1.481 +RecordAdoptedNode(JSCompartment *c);
1.482 +
1.483 +void
1.484 +RecordDonatedNode(JSCompartment *c);
1.485 +
1.486 +// This function may be used off-main-thread, in which case it is benignly
1.487 +// racey.
1.488 +bool
1.489 +ShouldDiscardSystemSource();
1.490 +
1.491 +} // namespace xpc
1.492 +
1.493 +namespace mozilla {
1.494 +namespace dom {
1.495 +
1.496 +typedef JSObject*
1.497 +(*DefineInterface)(JSContext *cx, JS::Handle<JSObject*> global,
1.498 + JS::Handle<jsid> id, bool defineOnGlobal);
1.499 +
1.500 +typedef JSObject*
1.501 +(*ConstructNavigatorProperty)(JSContext *cx, JS::Handle<JSObject*> naviObj);
1.502 +
1.503 +// Check whether a constructor should be enabled for the given object.
1.504 +// Note that the object should NOT be an Xray, since Xrays will end up
1.505 +// defining constructors on the underlying object.
1.506 +// This is a typedef for the function type itself, not the function
1.507 +// pointer, so it's more obvious that pointers to a ConstructorEnabled
1.508 +// can be null.
1.509 +typedef bool
1.510 +(ConstructorEnabled)(JSContext* cx, JS::Handle<JSObject*> obj);
1.511 +
1.512 +void
1.513 +Register(nsScriptNameSpaceManager* aNameSpaceManager);
1.514 +
1.515 +/**
1.516 + * A test for whether WebIDL methods that should only be visible to
1.517 + * chrome or XBL scopes should be exposed.
1.518 + */
1.519 +bool IsChromeOrXBL(JSContext* cx, JSObject* /* unused */);
1.520 +
1.521 +} // namespace dom
1.522 +} // namespace mozilla
1.523 +
1.524 +#endif
