gecko-dev/dom/base/nsJSUtils.cpp

389 lines
12 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */
/**
* This is not a generated file. It contains common utility functions
* invoked from the JavaScript code generated from IDL interfaces.
* The goal of the utility functions is to cut down on the size of
* the generated code itself.
*/
#include "nsJSUtils.h"
#include "jsapi.h"
#include "jsfriendapi.h"
#include "nsIScriptContext.h"
#include "nsIScriptGlobalObject.h"
#include "nsIXPConnect.h"
#include "nsCOMPtr.h"
#include "nsIScriptSecurityManager.h"
#include "nsPIDOMWindow.h"
#include "GeckoProfiler.h"
#include "nsJSPrincipals.h"
#include "xpcpublic.h"
#include "nsContentUtils.h"
#include "nsGlobalWindow.h"
#include "mozilla/dom/BindingUtils.h"
#include "mozilla/dom/Date.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/ScriptSettings.h"
using namespace mozilla::dom;
bool
nsJSUtils::GetCallingLocation(JSContext* aContext, nsACString& aFilename,
uint32_t* aLineno, uint32_t* aColumn)
{
JS::AutoFilename filename;
if (!JS::DescribeScriptedCaller(aContext, &filename, aLineno, aColumn)) {
return false;
}
aFilename.Assign(filename.get());
return true;
}
bool
nsJSUtils::GetCallingLocation(JSContext* aContext, nsAString& aFilename,
uint32_t* aLineno, uint32_t* aColumn)
{
JS::AutoFilename filename;
if (!JS::DescribeScriptedCaller(aContext, &filename, aLineno, aColumn)) {
return false;
}
aFilename.Assign(NS_ConvertUTF8toUTF16(filename.get()));
return true;
}
nsIScriptGlobalObject *
nsJSUtils::GetStaticScriptGlobal(JSObject* aObj)
{
if (!aObj)
return nullptr;
return xpc::WindowGlobalOrNull(aObj);
}
nsIScriptContext *
nsJSUtils::GetStaticScriptContext(JSObject* aObj)
{
nsIScriptGlobalObject *nativeGlobal = GetStaticScriptGlobal(aObj);
if (!nativeGlobal)
return nullptr;
return nativeGlobal->GetScriptContext();
}
uint64_t
nsJSUtils::GetCurrentlyRunningCodeInnerWindowID(JSContext *aContext)
{
if (!aContext)
return 0;
nsGlobalWindow* win = xpc::CurrentWindowOrNull(aContext);
return win ? win->WindowID() : 0;
}
nsresult
nsJSUtils::CompileFunction(AutoJSAPI& jsapi,
JS::AutoObjectVector& aScopeChain,
JS::CompileOptions& aOptions,
const nsACString& aName,
uint32_t aArgCount,
const char** aArgArray,
const nsAString& aBody,
JSObject** aFunctionObject)
{
JSContext* cx = jsapi.cx();
MOZ_ASSERT(js::GetEnterCompartmentDepth(cx) > 0);
MOZ_ASSERT_IF(aScopeChain.length() != 0,
js::IsObjectInContextCompartment(aScopeChain[0], cx));
MOZ_ASSERT_IF(aOptions.versionSet, aOptions.version != JSVERSION_UNKNOWN);
// Do the junk Gecko is supposed to do before calling into JSAPI.
for (size_t i = 0; i < aScopeChain.length(); ++i) {
JS::ExposeObjectToActiveJS(aScopeChain[i]);
}
// Compile.
JS::Rooted<JSFunction*> fun(cx);
if (!JS::CompileFunction(cx, aScopeChain, aOptions,
PromiseFlatCString(aName).get(),
aArgCount, aArgArray,
PromiseFlatString(aBody).get(),
aBody.Length(), &fun))
{
return NS_ERROR_FAILURE;
}
*aFunctionObject = JS_GetFunctionObject(fun);
return NS_OK;
}
nsresult
nsJSUtils::EvaluateString(JSContext* aCx,
const nsAString& aScript,
JS::Handle<JSObject*> aEvaluationGlobal,
JS::CompileOptions& aCompileOptions,
const EvaluateOptions& aEvaluateOptions,
JS::MutableHandle<JS::Value> aRetValue)
{
const nsPromiseFlatString& flatScript = PromiseFlatString(aScript);
JS::SourceBufferHolder srcBuf(flatScript.get(), aScript.Length(),
JS::SourceBufferHolder::NoOwnership);
return EvaluateString(aCx, srcBuf, aEvaluationGlobal, aCompileOptions,
aEvaluateOptions, aRetValue, nullptr);
}
nsresult
nsJSUtils::EvaluateString(JSContext* aCx,
JS::SourceBufferHolder& aSrcBuf,
JS::Handle<JSObject*> aEvaluationGlobal,
JS::CompileOptions& aCompileOptions,
const EvaluateOptions& aEvaluateOptions,
JS::MutableHandle<JS::Value> aRetValue,
void **aOffThreadToken)
{
PROFILER_LABEL("nsJSUtils", "EvaluateString",
js::ProfileEntry::Category::JS);
MOZ_ASSERT_IF(aCompileOptions.versionSet,
aCompileOptions.version != JSVERSION_UNKNOWN);
MOZ_ASSERT_IF(aEvaluateOptions.coerceToString, !aCompileOptions.noScriptRval);
MOZ_ASSERT(aCx == nsContentUtils::GetCurrentJSContext());
MOZ_ASSERT(aSrcBuf.get());
MOZ_ASSERT(js::GetGlobalForObjectCrossCompartment(aEvaluationGlobal) ==
aEvaluationGlobal);
MOZ_ASSERT_IF(aOffThreadToken, aCompileOptions.noScriptRval);
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(nsContentUtils::IsInMicroTask());
// Unfortunately, the JS engine actually compiles scripts with a return value
// in a different, less efficient way. Furthermore, it can't JIT them in many
// cases. So we need to be explicitly told whether the caller cares about the
// return value. Callers can do this by calling the other overload of
// EvaluateString() which calls this function with
// aCompileOptions.noScriptRval set to true.
aRetValue.setUndefined();
nsresult rv = NS_OK;
NS_ENSURE_TRUE(xpc::Scriptability::Get(aEvaluationGlobal).Allowed(), NS_OK);
bool ok = true;
// Scope the JSAutoCompartment so that we can later wrap the return value
// into the caller's cx.
{
JSAutoCompartment ac(aCx, aEvaluationGlobal);
// Now make sure to wrap the scope chain into the right compartment.
JS::AutoObjectVector scopeChain(aCx);
if (!scopeChain.reserve(aEvaluateOptions.scopeChain.length())) {
return NS_ERROR_OUT_OF_MEMORY;
}
for (size_t i = 0; i < aEvaluateOptions.scopeChain.length(); ++i) {
JS::ExposeObjectToActiveJS(aEvaluateOptions.scopeChain[i]);
scopeChain.infallibleAppend(aEvaluateOptions.scopeChain[i]);
if (!JS_WrapObject(aCx, scopeChain[i])) {
ok = false;
break;
}
}
if (ok && aOffThreadToken) {
JS::Rooted<JSScript*>
script(aCx, JS::FinishOffThreadScript(aCx, *aOffThreadToken));
*aOffThreadToken = nullptr; // Mark the token as having been finished.
if (script) {
ok = JS_ExecuteScript(aCx, scopeChain, script);
} else {
ok = false;
}
} else if (ok) {
ok = JS::Evaluate(aCx, scopeChain, aCompileOptions, aSrcBuf, aRetValue);
}
if (ok && aEvaluateOptions.coerceToString && !aRetValue.isUndefined()) {
JS::Rooted<JS::Value> value(aCx, aRetValue);
JSString* str = JS::ToString(aCx, value);
ok = !!str;
aRetValue.set(ok ? JS::StringValue(str) : JS::UndefinedValue());
}
}
if (!ok) {
if (JS_IsExceptionPending(aCx)) {
rv = NS_SUCCESS_DOM_SCRIPT_EVALUATION_THREW;
} else {
rv = NS_SUCCESS_DOM_SCRIPT_EVALUATION_THREW_UNCATCHABLE;
}
if (!aCompileOptions.noScriptRval) {
aRetValue.setUndefined();
}
}
// Wrap the return value into whatever compartment aCx was in.
if (ok && !aCompileOptions.noScriptRval) {
if (!JS_WrapValue(aCx, aRetValue)) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
return rv;
}
nsresult
nsJSUtils::EvaluateString(JSContext* aCx,
JS::SourceBufferHolder& aSrcBuf,
JS::Handle<JSObject*> aEvaluationGlobal,
JS::CompileOptions& aCompileOptions,
const EvaluateOptions& aEvaluateOptions,
JS::MutableHandle<JS::Value> aRetValue)
{
return EvaluateString(aCx, aSrcBuf, aEvaluationGlobal, aCompileOptions,
aEvaluateOptions, aRetValue, nullptr);
}
nsresult
nsJSUtils::EvaluateString(JSContext* aCx,
const nsAString& aScript,
JS::Handle<JSObject*> aEvaluationGlobal,
JS::CompileOptions& aCompileOptions)
{
EvaluateOptions options(aCx);
aCompileOptions.setNoScriptRval(true);
JS::RootedValue unused(aCx);
return EvaluateString(aCx, aScript, aEvaluationGlobal, aCompileOptions,
options, &unused);
}
nsresult
nsJSUtils::EvaluateString(JSContext* aCx,
JS::SourceBufferHolder& aSrcBuf,
JS::Handle<JSObject*> aEvaluationGlobal,
JS::CompileOptions& aCompileOptions,
void **aOffThreadToken)
{
EvaluateOptions options(aCx);
aCompileOptions.setNoScriptRval(true);
JS::RootedValue unused(aCx);
return EvaluateString(aCx, aSrcBuf, aEvaluationGlobal, aCompileOptions,
options, &unused, aOffThreadToken);
}
nsresult
nsJSUtils::CompileModule(JSContext* aCx,
JS::SourceBufferHolder& aSrcBuf,
JS::Handle<JSObject*> aEvaluationGlobal,
JS::CompileOptions &aCompileOptions,
JS::MutableHandle<JSObject*> aModule)
{
PROFILER_LABEL("nsJSUtils", "CompileModule",
js::ProfileEntry::Category::JS);
MOZ_ASSERT_IF(aCompileOptions.versionSet,
aCompileOptions.version != JSVERSION_UNKNOWN);
MOZ_ASSERT(aCx == nsContentUtils::GetCurrentJSContext());
MOZ_ASSERT(aSrcBuf.get());
MOZ_ASSERT(js::GetGlobalForObjectCrossCompartment(aEvaluationGlobal) ==
aEvaluationGlobal);
MOZ_ASSERT(JS::CurrentGlobalOrNull(aCx) == aEvaluationGlobal);
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(nsContentUtils::IsInMicroTask());
NS_ENSURE_TRUE(xpc::Scriptability::Get(aEvaluationGlobal).Allowed(), NS_OK);
if (!JS::CompileModule(aCx, aCompileOptions, aSrcBuf, aModule)) {
return NS_ERROR_FAILURE;
}
return NS_OK;
}
nsresult
nsJSUtils::ModuleDeclarationInstantiation(JSContext* aCx, JS::Handle<JSObject*> aModule)
{
PROFILER_LABEL("nsJSUtils", "ModuleDeclarationInstantiation",
js::ProfileEntry::Category::JS);
MOZ_ASSERT(aCx == nsContentUtils::GetCurrentJSContext());
MOZ_ASSERT(NS_IsMainThread());
NS_ENSURE_TRUE(xpc::Scriptability::Get(aModule).Allowed(), NS_OK);
if (!JS::ModuleDeclarationInstantiation(aCx, aModule)) {
return NS_ERROR_FAILURE;
}
return NS_OK;
}
nsresult
nsJSUtils::ModuleEvaluation(JSContext* aCx, JS::Handle<JSObject*> aModule)
{
PROFILER_LABEL("nsJSUtils", "ModuleEvaluation",
js::ProfileEntry::Category::JS);
MOZ_ASSERT(aCx == nsContentUtils::GetCurrentJSContext());
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(nsContentUtils::IsInMicroTask());
NS_ENSURE_TRUE(xpc::Scriptability::Get(aModule).Allowed(), NS_OK);
if (!JS::ModuleEvaluation(aCx, aModule)) {
return NS_ERROR_FAILURE;
}
return NS_OK;
}
/* static */
bool
nsJSUtils::GetScopeChainForElement(JSContext* aCx,
mozilla::dom::Element* aElement,
JS::AutoObjectVector& aScopeChain)
{
for (nsINode* cur = aElement; cur; cur = cur->GetScopeChainParent()) {
JS::RootedValue val(aCx);
if (!GetOrCreateDOMReflector(aCx, cur, &val)) {
return false;
}
if (!aScopeChain.append(&val.toObject())) {
return false;
}
}
return true;
}
/* static */
void
nsJSUtils::ResetTimeZone()
{
JS::ResetTimeZone();
}
//
// nsDOMJSUtils.h
//
bool nsAutoJSString::init(const JS::Value &v)
{
// Note: it's okay to use danger::GetJSContext here instead of AutoJSAPI,
// because the init() call below is careful not to run script (for instance,
// it only calls JS::ToString for non-object values).
JSContext* cx = danger::GetJSContext();
if (!init(cx, v)) {
JS_ClearPendingException(cx);
return false;
}
return true;
}