fune/js/src/frontend/BinTokenReaderBase.cpp

120 lines
2.8 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sts=4 et sw=4 tw=99:
* 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/. */
#include "frontend/BinTokenReaderBase.h"
#include "frontend/BinSource-macros.h"
#include "js/Result.h"
namespace js {
namespace frontend {
template<typename T> using ErrorResult = mozilla::GenericErrorResult<T>;
// We use signalling NaN (which doesn't exist in the JS syntax)
// to represent a `null` number.
const uint64_t NULL_FLOAT_REPRESENTATION = 0x7FF0000000000001;
void
BinTokenReaderBase::updateLatestKnownGood()
{
MOZ_ASSERT(current_ >= start_);
const size_t update = current_ - start_;
MOZ_ASSERT(update >= latestKnownGoodPos_);
latestKnownGoodPos_ = update;
}
ErrorResult<JS::Error&>
BinTokenReaderBase::raiseError(const char* description)
{
MOZ_ASSERT(!cx_->isExceptionPending());
TokenPos pos = this->pos();
JS_ReportErrorASCII(cx_, "BinAST parsing error: %s at offsets %u => %u",
description, pos.begin, pos.end);
return cx_->alreadyReportedError();
}
ErrorResult<JS::Error&>
BinTokenReaderBase::raiseOOM()
{
ReportOutOfMemory(cx_);
return cx_->alreadyReportedError();
}
ErrorResult<JS::Error&>
BinTokenReaderBase::raiseInvalidNumberOfFields(const BinKind kind, const uint32_t expected, const uint32_t got)
{
Sprinter out(cx_);
BINJS_TRY(out.init());
BINJS_TRY(out.printf("In %s, invalid number of fields: expected %u, got %u",
describeBinKind(kind), expected, got));
return raiseError(out.string());
}
ErrorResult<JS::Error&>
BinTokenReaderBase::raiseInvalidField(const char* kind, const BinField field)
{
Sprinter out(cx_);
BINJS_TRY(out.init());
BINJS_TRY(out.printf("In %s, invalid field '%s'", kind, describeBinField(field)));
return raiseError(out.string());
}
#ifdef DEBUG
bool
BinTokenReaderBase::hasRaisedError() const
{
return cx_->isExceptionPending();
}
#endif
size_t
BinTokenReaderBase::offset() const
{
return current_ - start_;
}
TokenPos
BinTokenReaderBase::pos()
{
return pos(offset());
}
TokenPos
BinTokenReaderBase::pos(size_t start)
{
TokenPos pos;
pos.begin = start;
pos.end = current_ - start_;
MOZ_ASSERT(pos.end >= pos.begin);
return pos;
}
JS::Result<Ok>
BinTokenReaderBase::readBuf(uint8_t* bytes, uint32_t len)
{
MOZ_ASSERT(!cx_->isExceptionPending());
MOZ_ASSERT(len > 0);
if (stop_ < current_ + len)
return raiseError("Buffer exceeds length");
for (uint32_t i = 0; i < len; ++i)
*bytes++ = *current_++;
return Ok();
}
JS::Result<uint8_t>
BinTokenReaderBase::readByte()
{
uint8_t byte;
MOZ_TRY(readBuf(&byte, 1));
return byte;
}
}
}