/* Copyright 2018 Mozilla Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
use super::{BinaryReader, BinaryReaderError, Operator, Result};
#[derive(Clone)]
pub struct OperatorsReader<'a> {
pub(crate) reader: BinaryReader<'a>,
}
impl<'a> OperatorsReader<'a> {
pub(crate) fn new<'b>(data: &'a [u8], offset: usize) -> OperatorsReader<'b>
where
'a: 'b,
{
OperatorsReader {
reader: BinaryReader::new_with_offset(data, offset),
}
}
pub fn eof(&self) -> bool {
self.reader.eof()
}
pub fn original_position(&self) -> usize {
self.reader.original_position()
}
pub fn ensure_end(&self) -> Result<()> {
if self.eof() {
return Ok(());
}
Err(BinaryReaderError::new(
"Unexpected data at the end of operators",
self.reader.original_position(),
))
}
pub fn read<'b>(&mut self) -> Result<Operator<'b>>
where
'a: 'b,
{
self.reader.read_operator()
}
pub fn into_iter_with_offsets<'b>(self) -> OperatorsIteratorWithOffsets<'b>
where
'a: 'b,
{
OperatorsIteratorWithOffsets {
reader: self,
err: false,
}
}
pub fn read_with_offset<'b>(&mut self) -> Result<(Operator<'b>, usize)>
where
'a: 'b,
{
let pos = self.reader.original_position();
Ok((self.read()?, pos))
}
}
impl<'a> IntoIterator for OperatorsReader<'a> {
type Item = Result<Operator<'a>>;
type IntoIter = OperatorsIterator<'a>;
/// Reads content of the code section.
///
/// # Examples
/// ```
/// use wasmparser::{Operator, CodeSectionReader, Result};
/// # let data: &[u8] = &[
/// # 0x01, 0x03, 0x00, 0x01, 0x0b];
/// let mut code_reader = CodeSectionReader::new(data, 0).unwrap();
/// for _ in 0..code_reader.get_count() {
/// let body = code_reader.read().expect("function body");
/// let mut op_reader = body.get_operators_reader().expect("op reader");
/// let ops = op_reader.into_iter().collect::<Result<Vec<Operator>>>().expect("ops");
/// assert!(
/// if let [Operator::Nop, Operator::End] = ops.as_slice() { true } else { false },
/// "found {:?}",
/// ops
/// );
/// }
/// ```
fn into_iter(self) -> Self::IntoIter {
OperatorsIterator {
reader: self,
err: false,
}
}
}
pub struct OperatorsIterator<'a> {
reader: OperatorsReader<'a>,
err: bool,
}
impl<'a> Iterator for OperatorsIterator<'a> {
type Item = Result<Operator<'a>>;
fn next(&mut self) -> Option<Self::Item> {
if self.err || self.reader.eof() {
return None;
}
let result = self.reader.read();
self.err = result.is_err();
Some(result)
}
}
pub struct OperatorsIteratorWithOffsets<'a> {
reader: OperatorsReader<'a>,
err: bool,
}
impl<'a> Iterator for OperatorsIteratorWithOffsets<'a> {
type Item = Result<(Operator<'a>, usize)>;
/// Reads content of the code section with offsets.
///
/// # Examples
/// ```
/// use wasmparser::{Operator, CodeSectionReader, Result};
/// # let data: &[u8] = &[
/// # 0x01, 0x03, 0x00, /* offset = 23 */ 0x01, 0x0b];
/// let mut code_reader = CodeSectionReader::new(data, 20).unwrap();
/// for _ in 0..code_reader.get_count() {
/// let body = code_reader.read().expect("function body");
/// let mut op_reader = body.get_operators_reader().expect("op reader");
/// let ops = op_reader.into_iter_with_offsets().collect::<Result<Vec<(Operator, usize)>>>().expect("ops");
/// assert!(
/// if let [(Operator::Nop, 23), (Operator::End, 24)] = ops.as_slice() { true } else { false },
/// "found {:?}",
/// ops
/// );
/// }
/// ```
fn next(&mut self) -> Option<Self::Item> {
if self.err || self.reader.eof() {
return None;
}
let result = self.reader.read_with_offset();
self.err = result.is_err();
Some(result)
}
}