1/* Copyright 2019 Mozilla Foundation
2 *
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16use crate::{BinaryReader, FromReader, Result, SectionLimited};
17
18/// A reader for the producers custom section of a WebAssembly module.
19///
20/// # Examples
21///
22/// ```
23/// # let data: &[u8] = &[0x01, 0x08, 0x6c, 0x61, 0x6e, 0x67, 0x75, 0x61, 0x67, 0x65,
24/// # 0x02, 0x03, 0x77, 0x61, 0x74, 0x01, 0x31, 0x01, 0x43, 0x03, 0x39, 0x2e, 0x30];
25/// # use wasmparser::{ProducersSectionReader, ProducersFieldValue, Result, BinaryReader};
26/// let reader = BinaryReader::new(data, 0);
27/// let reader = ProducersSectionReader::new(reader).expect("producers reader");
28/// let field = reader.into_iter().next().unwrap().expect("producers field");
29/// assert!(field.name == "language");
30/// let value = field.values.into_iter().collect::<Result<Vec<_>>>().expect("values");
31/// assert!(value.len() == 2);
32/// assert!(value[0].name == "wat" && value[0].version == "1");
33/// assert!(value[1].name == "C" && value[1].version == "9.0");
34/// ```
35pub type ProducersSectionReader<'a> = SectionLimited<'a, ProducersField<'a>>;
36
37/// A field from the producers custom section.
38#[derive(Debug, Clone)]
39pub struct ProducersField<'a> {
40 /// The name of the field.
41 pub name: &'a str,
42 /// The values specified for this field
43 pub values: SectionLimited<'a, ProducersFieldValue<'a>>,
44}
45
46impl<'a> FromReader<'a> for ProducersField<'a> {
47 fn from_reader(reader: &mut BinaryReader<'a>) -> Result<Self> {
48 let offset: usize = reader.original_position();
49 let name: &'a str = reader.read_string()?;
50 match name {
51 "language" | "sdk" | "processed-by" => {}
52 _ => bail!(offset, "invalid producers field name: `{name}`"),
53 }
54 let values: BinaryReader<'a> = reader.skip(|reader: &mut BinaryReader<'a>| {
55 // FIXME(#188) ideally shouldn't need to skip here
56 for _ in 0..reader.read_var_u32()? {
57 reader.skip_string()?;
58 reader.skip_string()?;
59 }
60 Ok(())
61 })?;
62 Ok(ProducersField {
63 name,
64 values: SectionLimited::new(reader:values)?,
65 })
66 }
67}
68
69/// Represents a field value in the producers custom section.
70#[derive(Debug, Copy, Clone)]
71pub struct ProducersFieldValue<'a> {
72 /// The field name.
73 pub name: &'a str,
74 /// The field version.
75 pub version: &'a str,
76}
77
78impl<'a> FromReader<'a> for ProducersFieldValue<'a> {
79 fn from_reader(reader: &mut BinaryReader<'a>) -> Result<Self> {
80 let name: &'a str = reader.read_string()?;
81 let version: &'a str = reader.read_string()?;
82 Ok(ProducersFieldValue { name, version })
83 }
84}
85