packattack_derive/
lib.rs

1#![feature(arbitrary_enum_discriminant)]
2#![crate_type = "proc-macro"]
3
4#[macro_use]
5extern crate quote;
6
7extern crate proc_macro;
8
9extern crate proc_macro2;
10
11use proc_macro::TokenStream;
12
13use syn::{Data};
14
15mod enum_from_bitreader;
16mod struct_from_bitreader;
17mod util;
18
19#[proc_macro_derive(FromBitReader, attributes(size_in_bits, expose, flag, length))]
20pub fn from_bit_reader(input: TokenStream) -> TokenStream {
21    let ast: syn::DeriveInput = syn::parse(input).unwrap();
22    let name = &ast.ident;
23
24    match ast.data {
25        Data::Enum(ref data_enum) =>
26        {
27            //gather size attribute
28            //we need to know the size of the discriminant of the enum 
29            //so we can allocate the right size for it
30            if let Some(size_in_bits) = util::get_meta_attribute(&ast.attrs, "size_in_bits")
31            {
32                enum_from_bitreader::enum_from_bitreader(&data_enum.variants, name, size_in_bits)
33            }
34            else
35            {
36                panic!("No size_in_bits attribute found!")
37            }
38        }
39        Data::Struct(ref data_struct) =>
40        {
41            struct_from_bitreader::struct_from_bitreader(&data_struct.fields, name)
42        },
43        _ => panic!(
44            "deriving `FromBitReader` can be applied only to enums and structs, {} is neither",
45            name
46        ),
47    }
48}
packattack_derive/lib.rs

packattack_derive/
lib.rs
