/* 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 crate::{
BinaryReader, BinaryReaderError, Range, Result, SectionIteratorLimited, SectionReader,
SectionWithLimitedItems, TypeDef,
};
#[derive(Clone)]
pub struct TypeSectionReader<'a> {
reader: BinaryReader<'a>,
count: u32,
}
impl<'a> TypeSectionReader<'a> {
pub fn new(data: &'a [u8], offset: usize) -> Result<TypeSectionReader<'a>> {
let mut reader = BinaryReader::new_with_offset(data, offset);
let count = reader.read_var_u32()?;
Ok(TypeSectionReader { reader, count })
}
pub fn original_position(&self) -> usize {
self.reader.original_position()
}
pub fn get_count(&self) -> u32 {
self.count
}
/// Reads content of the type section.
///
/// # Examples
/// ```
/// use wasmparser::TypeSectionReader;
/// # let data: &[u8] = &[0x01, 0x60, 0x00, 0x00];
/// let mut type_reader = TypeSectionReader::new(data, 0).unwrap();
/// for _ in 0..type_reader.get_count() {
/// let ty = type_reader.read().expect("type");
/// println!("Type {:?}", ty);
/// }
/// ```
pub fn read(&mut self) -> Result<TypeDef<'a>> {
Ok(match self.reader.read_u8()? {
0x60 => TypeDef::Func(self.reader.read_func_type()?),
0x61 => TypeDef::Module(self.reader.read_module_type()?),
0x62 => TypeDef::Instance(self.reader.read_instance_type()?),
_ => {
return Err(BinaryReaderError::new(
"invalid leading byte in type definition",
self.original_position() - 1,
))
}
})
}
}
impl<'a> SectionReader for TypeSectionReader<'a> {
type Item = TypeDef<'a>;
fn read(&mut self) -> Result<Self::Item> {
TypeSectionReader::read(self)
}
fn eof(&self) -> bool {
self.reader.eof()
}
fn original_position(&self) -> usize {
TypeSectionReader::original_position(self)
}
fn range(&self) -> Range {
self.reader.range()
}
}
impl<'a> SectionWithLimitedItems for TypeSectionReader<'a> {
fn get_count(&self) -> u32 {
TypeSectionReader::get_count(self)
}
}
impl<'a> IntoIterator for TypeSectionReader<'a> {
type Item = Result<TypeDef<'a>>;
type IntoIter = SectionIteratorLimited<TypeSectionReader<'a>>;
/// Implements iterator over the type section.
///
/// # Examples
/// ```
/// use wasmparser::TypeSectionReader;
/// # let data: &[u8] = &[0x01, 0x60, 0x00, 0x00];
/// let mut type_reader = TypeSectionReader::new(data, 0).unwrap();
/// for ty in type_reader {
/// println!("Type {:?}", ty);
/// }
/// ```
fn into_iter(self) -> Self::IntoIter {
SectionIteratorLimited::new(self)
}
}