Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 336 insertions, 0 deletions

diff --git a/dom/base/JSExecutionContext.cpp b/dom/base/JSExecutionContext.cpp
new file mode 100644
index 0000000000..510ef68df7
--- /dev/null
+++ b/dom/base/JSExecutionContext.cpp
@@ -0,0 +1,336 @@
+/* -*- 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 "mozilla/dom/JSExecutionContext.h"
+
+#include <utility>
+#include "MainThreadUtils.h"
+#include "js/CompilationAndEvaluation.h"
+#include "js/CompileOptions.h"
+#include "js/Conversions.h"
+#include "js/HeapAPI.h"
+#include "js/OffThreadScriptCompilation.h"
+#include "js/ProfilingCategory.h"
+#include "js/Promise.h"
+#include "js/SourceText.h"
+#include "js/Transcoding.h"
+#include "js/Value.h"
+#include "js/Wrapper.h"
+#include "jsapi.h"
+#include "mozilla/CycleCollectedJSContext.h"
+#include "mozilla/Likely.h"
+#include "nsContentUtils.h"
+#include "nsTPromiseFlatString.h"
+#include "xpcpublic.h"
+
+#if !defined(DEBUG) && !defined(MOZ_ENABLE_JS_DUMP)
+#  include "mozilla/StaticPrefs_browser.h"
+#endif
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+static nsresult EvaluationExceptionToNSResult(JSContext* aCx) {
+  if (JS_IsExceptionPending(aCx)) {
+    return NS_SUCCESS_DOM_SCRIPT_EVALUATION_THREW;
+  }
+  return NS_SUCCESS_DOM_SCRIPT_EVALUATION_THREW_UNCATCHABLE;
+}
+
+JSExecutionContext::JSExecutionContext(JSContext* aCx,
+                                       JS::Handle<JSObject*> aGlobal)
+    :
+#ifdef MOZ_GECKO_PROFILER
+      mAutoProfilerLabel("JSExecutionContext",
+                         /* dynamicStr */ nullptr,
+                         JS::ProfilingCategoryPair::JS),
+#endif
+      mCx(aCx),
+      mRealm(aCx, aGlobal),
+      mRetValue(aCx),
+      mScopeChain(aCx),
+      mScript(aCx),
+      mRv(NS_OK),
+      mSkip(false),
+      mCoerceToString(false),
+      mEncodeBytecode(false)
+#ifdef DEBUG
+      ,
+      mWantsReturnValue(false),
+      mExpectScopeChain(false),
+      mScriptUsed(false)
+#endif
+{
+  MOZ_ASSERT(aCx == nsContentUtils::GetCurrentJSContext());
+  MOZ_ASSERT(NS_IsMainThread());
+  MOZ_ASSERT(CycleCollectedJSContext::Get() &&
+             CycleCollectedJSContext::Get()->MicroTaskLevel());
+  MOZ_ASSERT(mRetValue.isUndefined());
+
+  MOZ_ASSERT(JS_IsGlobalObject(aGlobal));
+  if (MOZ_UNLIKELY(!xpc::Scriptability::Get(aGlobal).Allowed())) {
+    mSkip = true;
+    mRv = NS_OK;
+  }
+}
+
+void JSExecutionContext::SetScopeChain(
+    JS::HandleVector<JSObject*> aScopeChain) {
+  if (mSkip) {
+    return;
+  }
+
+#ifdef DEBUG
+  mExpectScopeChain = true;
+#endif
+  // Now make sure to wrap the scope chain into the right compartment.
+  if (!mScopeChain.reserve(aScopeChain.length())) {
+    mSkip = true;
+    mRv = NS_ERROR_OUT_OF_MEMORY;
+    return;
+  }
+
+  for (size_t i = 0; i < aScopeChain.length(); ++i) {
+    JS::ExposeObjectToActiveJS(aScopeChain[i]);
+    mScopeChain.infallibleAppend(aScopeChain[i]);
+    if (!JS_WrapObject(mCx, mScopeChain[i])) {
+      mSkip = true;
+      mRv = NS_ERROR_OUT_OF_MEMORY;
+      return;
+    }
+  }
+}
+
+nsresult JSExecutionContext::JoinCompile(JS::OffThreadToken** aOffThreadToken) {
+  if (mSkip) {
+    return mRv;
+  }
+
+  MOZ_ASSERT(!mWantsReturnValue);
+  MOZ_ASSERT(!mExpectScopeChain);
+  MOZ_ASSERT(!mScript);
+
+  if (mEncodeBytecode) {
+    mScript.set(JS::FinishOffThreadScriptAndStartIncrementalEncoding(
+        mCx, *aOffThreadToken));
+  } else {
+    mScript.set(JS::FinishOffThreadScript(mCx, *aOffThreadToken));
+  }
+  *aOffThreadToken = nullptr;  // Mark the token as having been finished.
+  if (!mScript) {
+    mSkip = true;
+    mRv = EvaluationExceptionToNSResult(mCx);
+    return mRv;
+  }
+
+  return NS_OK;
+}
+
+template <typename Unit>
+nsresult JSExecutionContext::InternalCompile(
+    JS::CompileOptions& aCompileOptions, JS::SourceText<Unit>& aSrcBuf) {
+  if (mSkip) {
+    return mRv;
+  }
+
+  MOZ_ASSERT(aSrcBuf.get());
+  MOZ_ASSERT(mRetValue.isUndefined());
+#ifdef DEBUG
+  mWantsReturnValue = !aCompileOptions.noScriptRval;
+#endif
+
+  MOZ_ASSERT(!mScript);
+
+  if (mScopeChain.length() != 0) {
+    aCompileOptions.setNonSyntacticScope(true);
+  }
+
+  if (mEncodeBytecode) {
+    mScript =
+        JS::CompileAndStartIncrementalEncoding(mCx, aCompileOptions, aSrcBuf);
+  } else {
+    mScript = JS::Compile(mCx, aCompileOptions, aSrcBuf);
+  }
+
+  if (!mScript) {
+    mSkip = true;
+    mRv = EvaluationExceptionToNSResult(mCx);
+    return mRv;
+  }
+
+  return NS_OK;
+}
+
+nsresult JSExecutionContext::Compile(JS::CompileOptions& aCompileOptions,
+                                     JS::SourceText<char16_t>& aSrcBuf) {
+  return InternalCompile(aCompileOptions, aSrcBuf);
+}
+
+nsresult JSExecutionContext::Compile(JS::CompileOptions& aCompileOptions,
+                                     JS::SourceText<Utf8Unit>& aSrcBuf) {
+  return InternalCompile(aCompileOptions, aSrcBuf);
+}
+
+nsresult JSExecutionContext::Compile(JS::CompileOptions& aCompileOptions,
+                                     const nsAString& aScript) {
+  if (mSkip) {
+    return mRv;
+  }
+
+  const nsPromiseFlatString& flatScript = PromiseFlatString(aScript);
+  JS::SourceText<char16_t> srcBuf;
+  if (!srcBuf.init(mCx, flatScript.get(), flatScript.Length(),
+                   JS::SourceOwnership::Borrowed)) {
+    mSkip = true;
+    mRv = EvaluationExceptionToNSResult(mCx);
+    return mRv;
+  }
+
+  return Compile(aCompileOptions, srcBuf);
+}
+
+nsresult JSExecutionContext::Decode(JS::CompileOptions& aCompileOptions,
+                                    mozilla::Vector<uint8_t>& aBytecodeBuf,
+                                    size_t aBytecodeIndex) {
+  if (mSkip) {
+    return mRv;
+  }
+
+  MOZ_ASSERT(!mWantsReturnValue);
+  JS::TranscodeResult tr = JS::DecodeScriptMaybeStencil(
+      mCx, aCompileOptions, aBytecodeBuf, &mScript, aBytecodeIndex);
+  // These errors are external parameters which should be handled before the
+  // decoding phase, and which are the only reasons why you might want to
+  // fallback on decoding failures.
+  MOZ_ASSERT(tr != JS::TranscodeResult_Failure_BadBuildId &&
+             tr != JS::TranscodeResult_Failure_WrongCompileOption);
+  if (tr != JS::TranscodeResult_Ok) {
+    mSkip = true;
+    mRv = NS_ERROR_DOM_JS_DECODING_ERROR;
+    return mRv;
+  }
+
+  return mRv;
+}
+
+nsresult JSExecutionContext::JoinDecode(JS::OffThreadToken** aOffThreadToken) {
+  if (mSkip) {
+    return mRv;
+  }
+
+  MOZ_ASSERT(!mWantsReturnValue);
+  MOZ_ASSERT(!mExpectScopeChain);
+  mScript.set(JS::FinishOffThreadScriptDecoder(mCx, *aOffThreadToken));
+  *aOffThreadToken = nullptr;  // Mark the token as having been finished.
+  if (!mScript) {
+    mSkip = true;
+    mRv = EvaluationExceptionToNSResult(mCx);
+    return mRv;
+  }
+
+  return NS_OK;
+}
+
+nsresult JSExecutionContext::JoinDecodeBinAST(
+    JS::OffThreadToken** aOffThreadToken) {
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+nsresult JSExecutionContext::DecodeBinAST(JS::CompileOptions& aCompileOptions,
+                                          const uint8_t* aBuf, size_t aLength) {
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+JSScript* JSExecutionContext::GetScript() {
+#ifdef DEBUG
+  MOZ_ASSERT(!mSkip);
+  MOZ_ASSERT(mScript);
+  mScriptUsed = true;
+#endif
+
+  return MaybeGetScript();
+}
+
+JSScript* JSExecutionContext::MaybeGetScript() { return mScript; }
+
+nsresult JSExecutionContext::ExecScript() {
+  if (mSkip) {
+    return mRv;
+  }
+
+  MOZ_ASSERT(mScript);
+
+  if (!JS_ExecuteScript(mCx, mScopeChain, mScript)) {
+    mSkip = true;
+    mRv = EvaluationExceptionToNSResult(mCx);
+    return mRv;
+  }
+
+  return NS_OK;
+}
+
+static bool IsPromiseValue(JSContext* aCx, JS::Handle<JS::Value> aValue) {
+  if (!aValue.isObject()) {
+    return false;
+  }
+
+  // We only care about Promise here, so CheckedUnwrapStatic is fine.
+  JS::Rooted<JSObject*> obj(aCx, js::CheckedUnwrapStatic(&aValue.toObject()));
+  if (!obj) {
+    return false;
+  }
+
+  return JS::IsPromiseObject(obj);
+}
+
+nsresult JSExecutionContext::ExecScript(
+    JS::MutableHandle<JS::Value> aRetValue) {
+  if (mSkip) {
+    aRetValue.setUndefined();
+    return mRv;
+  }
+
+  MOZ_ASSERT(mScript);
+  MOZ_ASSERT(mWantsReturnValue);
+
+  if (!JS_ExecuteScript(mCx, mScopeChain, mScript, aRetValue)) {
+    mSkip = true;
+    mRv = EvaluationExceptionToNSResult(mCx);
+    return mRv;
+  }
+
+#ifdef DEBUG
+  mWantsReturnValue = false;
+#endif
+  if (mCoerceToString && IsPromiseValue(mCx, aRetValue)) {
+    // We're a javascript: url and we should treat Promise return values as
+    // undefined.
+    //
+    // Once bug 1477821 is fixed this code might be able to go away, or will
+    // become enshrined in the spec, depending.
+    aRetValue.setUndefined();
+  }
+
+  if (mCoerceToString && !aRetValue.isUndefined()) {
+    JSString* str = JS::ToString(mCx, aRetValue);
+    if (!str) {
+      // ToString can be a function call, so an exception can be raised while
+      // executing the function.
+      mSkip = true;
+      return EvaluationExceptionToNSResult(mCx);
+    }
+    aRetValue.set(JS::StringValue(str));
+  }
+
+  return NS_OK;
+}