gecko-dev/js/public/Transcoding.h

101 lines
3.7 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
/*
* Structures and functions for transcoding compiled scripts and functions to
* and from memory.
*/
#ifndef js_Transcoding_h
#define js_Transcoding_h
#include "mozilla/Range.h" // mozilla::Range
#include "mozilla/Vector.h" // mozilla::Vector
#include <stddef.h> // size_t
#include <stdint.h> // uint8_t, uint32_t
#include "js/RootingAPI.h" // JS::Handle, JS::MutableHandle
struct JSContext;
class JSFunction;
class JSObject;
class JSScript;
namespace JS {
using TranscodeBuffer = mozilla::Vector<uint8_t>;
using TranscodeRange = mozilla::Range<uint8_t>;
struct TranscodeSource final {
TranscodeSource(const TranscodeRange& range_, const char* file, uint32_t line)
: range(range_), filename(file), lineno(line) {}
const TranscodeRange range;
const char* filename;
const uint32_t lineno;
};
using TranscodeSources = mozilla::Vector<TranscodeSource>;
enum TranscodeResult : uint8_t {
// Successful encoding / decoding.
TranscodeResult_Ok = 0,
// A warning message, is set to the message out-param.
TranscodeResult_Failure = 0x10,
TranscodeResult_Failure_BadBuildId = TranscodeResult_Failure | 0x1,
TranscodeResult_Failure_RunOnceNotSupported = TranscodeResult_Failure | 0x2,
TranscodeResult_Failure_AsmJSNotSupported = TranscodeResult_Failure | 0x3,
TranscodeResult_Failure_BadDecode = TranscodeResult_Failure | 0x4,
TranscodeResult_Failure_WrongCompileOption = TranscodeResult_Failure | 0x5,
TranscodeResult_Failure_NotInterpretedFun = TranscodeResult_Failure | 0x6,
// There is a pending exception on the context.
TranscodeResult_Throw = 0x20
};
extern JS_PUBLIC_API TranscodeResult EncodeScript(JSContext* cx,
TranscodeBuffer& buffer,
Handle<JSScript*> script);
extern JS_PUBLIC_API TranscodeResult EncodeInterpretedFunction(
JSContext* cx, TranscodeBuffer& buffer, Handle<JSObject*> funobj);
extern JS_PUBLIC_API TranscodeResult
DecodeScript(JSContext* cx, TranscodeBuffer& buffer,
MutableHandle<JSScript*> scriptp, size_t cursorIndex = 0);
extern JS_PUBLIC_API TranscodeResult
DecodeScript(JSContext* cx, const TranscodeRange& range,
MutableHandle<JSScript*> scriptp);
extern JS_PUBLIC_API TranscodeResult DecodeInterpretedFunction(
JSContext* cx, TranscodeBuffer& buffer, MutableHandle<JSFunction*> funp,
size_t cursorIndex = 0);
// Register an encoder on the given script source, such that all functions can
// be encoded as they are parsed. This strategy is used to avoid blocking the
// main thread in a non-interruptible way.
//
// The |script| argument of |StartIncrementalEncoding| and
// |FinishIncrementalEncoding| should be the top-level script returned either as
// an out-param of any of the |Compile| functions, or the result of
// |FinishOffThreadScript|.
//
// The |buffer| argument of |FinishIncrementalEncoding| is used for appending
// the encoded bytecode into the buffer. If any of these functions failed, the
// content of |buffer| would be undefined.
extern JS_PUBLIC_API bool StartIncrementalEncoding(JSContext* cx,
Handle<JSScript*> script);
extern JS_PUBLIC_API bool FinishIncrementalEncoding(JSContext* cx,
Handle<JSScript*> script,
TranscodeBuffer& buffer);
} // namespace JS
#endif /* js_Transcoding_h */