1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171

#[macro_use]
extern crate cpp_syn as syn;

#[macro_use]
extern crate cpp_synom as synom;

#[macro_use]
extern crate quote;

use std::collections::hash_map::DefaultHasher;
use std::hash::{Hash, Hasher};

use syn::{Ident, Spanned, Ty};

pub const VERSION: &'static str = env!("CARGO_PKG_VERSION");

pub const LIB_NAME: &'static str = "librust_cpp_generated.a";
pub const MSVC_LIB_NAME: &'static str = "rust_cpp_generated.lib";

/// This constant is expected to be a unique string within the compiled binary
/// which preceeds a definition of the metadata. It begins with
/// rustcpp~metadata, which is printable to make it easier to locate when
/// looking at a binary dump of the metadata.
///
/// NOTE: In the future we may want to use a object file parser and a custom
/// section rather than depending on this string being unique.
#[cfg_attr(rustfmt, rustfmt_skip)]
pub const STRUCT_METADATA_MAGIC: [u8; 128] = [
    b'r', b'u', b's', b't', b'c', b'p', b'p', b'~',
    b'm', b'e', b't', b'a', b'd', b'a', b't', b'a',
    91,  74,  112, 213, 165, 185, 214, 120, 179, 17,  185, 25,  182, 253, 82,  118,
    148, 29,  139, 208, 59,  153, 78,  137, 230, 54,  26,  177, 232, 121, 132, 166,
    44,  106, 218, 57,  158, 33,  69,  32,  54,  204, 123, 226, 99,  117, 60,  173,
    112, 61,  56,  174, 117, 141, 126, 249, 79,  159, 6,   119, 2,   129, 147, 66,
    135, 136, 212, 252, 231, 105, 239, 91,  96,  232, 113, 94,  164, 255, 152, 144,
    64,  207, 192, 90,  225, 171, 59,  154, 60,  2,   0,   191, 114, 182, 38,  134,
    134, 183, 212, 227, 31,  217, 12,  5,   65,  221, 150, 59,  230, 96,  73,  62,
];

#[derive(Clone, Debug, Hash, PartialEq, Eq)]
pub struct Capture {
    pub mutable: bool,
    pub name: Ident,
    pub cpp: String,
}

#[derive(Clone, Debug, Hash, PartialEq, Eq)]
pub struct ClosureSig {
    pub captures: Vec<Capture>,
    pub ret: Ty,
    pub cpp: String,
    pub std_body: String,
}

impl ClosureSig {
    pub fn name_hash(&self) -> u64 {
        // XXX: Use a better hasher than the default?
        let mut hasher = DefaultHasher::new();
        self.hash(&mut hasher);
        hasher.finish()
    }

    pub fn extern_name(&self) -> Ident {
        format!("__cpp_closure_{}", self.name_hash()).into()
    }
}

#[derive(Clone, Debug, PartialEq, Eq)]
pub struct Closure {
    pub sig: ClosureSig,
    pub body: Spanned<String>,
}

pub enum Macro {
    Closure(Closure),
    Lit(Spanned<String>),
}

pub mod parsing {
    use syn::parse::{ident, string, tt, ty};
    use syn::{Spanned, Ty, DUMMY_SPAN};
    use super::{Capture, Closure, ClosureSig, Macro};

    macro_rules! mac_body {
        ($i: expr, $submac:ident!( $($args:tt)* )) => {
            delimited!(
                $i,
                alt!(punct!("[") | punct!("(") | punct!("{")),
                $submac!($($args)*),
                alt!(punct!("]") | punct!(")") | punct!("}"))
            )
        };
        ($i:expr, $e:expr) => {
            mac_body!($i, call!($e))
        };
    }

    named!(name_as_string -> Capture,
           do_parse!(
               is_mut: option!(keyword!("mut")) >>
                   id: ident >>
                   keyword!("as") >>
                   cty: string >>
                   (Capture {
                       mutable: is_mut.is_some(),
                       name: id,
                       cpp: cty.value
                   })
           ));

    named!(captures -> Vec<Capture>,
           delimited!(
               punct!("["),
               terminated_list!(
                   punct!(","),
                   name_as_string
               ),
               punct!("]")));

    named!(ret_ty -> (Ty, String),
           alt!(
               do_parse!(punct!("->") >>
                         rty: ty >>
                         keyword!("as") >>
                         cty: string >>
                         ((rty, cty.value))) |
               value!((Ty::Tup(Vec::new()), "void".to_owned()))
           ));

    named!(code_block -> Spanned<String>,
           alt!(
               do_parse!(s: string >> (Spanned {
                   node: s.value,
                   span: DUMMY_SPAN,
               })) |
               // XXX: This is really inefficient and means that things like ++y
               // will parse incorrectly (as we care about the layout of the
               // original source) so consider this a temporary monkey patch.
               // Once we get spans we can work past it.
               delimited!(punct!("{"), spanned!(many0!(tt)), punct!("}")) => {
                   |Spanned{ node, span }| Spanned {
                       node: quote!(#(#node)*).to_string(),
                       span: span
                   }
               }
           ));

    named!(pub cpp_closure -> Closure,
           do_parse!(captures: captures >>
                     ret: ret_ty >>
                     code: code_block >>
                     (Closure {
                         sig: ClosureSig {
                             captures: captures,
                             ret: ret.0,
                             cpp: ret.1,
                             std_body: code.node.clone(),
                         },
                         body: code,
                     })));

    named!(pub build_macro -> Macro , mac_body!(alt!(
        cpp_closure => { |c| Macro::Closure(c) } |
        code_block => { |b| Macro::Lit(b) }
    )));

    named!(pub expand_macro -> Closure, mac_body!(
        map!(tuple!(
            punct!("@"), keyword!("TYPE"), cpp_closure
        ), (|(_, _, x)| x))));
}