fontsan/
ffi.rs

1// Copyright 2015 The Servo Project Developers.
2//
3// Use of this source code is governed by a BSD-style license
4// that can be found in the LICENSE file.
5
6use std::io::{self, Seek, SeekFrom, Write};
7use std::slice;
8
9use libc::{c_int, off_t, size_t};
10
11pub trait Wr: Write + Seek {}
12impl<T> Wr for T where T: Write + Seek {}
13
14pub struct RustOTSStream<'a> {
15    pub wr: &'a mut (dyn Wr + 'a),
16    pub error: Option<io::Error>,
17}
18
19#[allow(improper_ctypes)]
20extern "C" {
21    pub fn RustOTS_Process(stream: *mut RustOTSStream, data: *const u8, len: size_t) -> c_int;
22}
23
24#[no_mangle]
25pub unsafe extern "C" fn RustOTSStream_WriteRaw(
26    stream: *mut RustOTSStream,
27    data: *const u8,
28    len: size_t,
29) -> c_int {
30    let buf = slice::from_raw_parts(data, len as usize);
31    // Return success/failure only!
32    match (*stream).wr.write_all(buf) {
33        Ok(()) => 1,
34        Err(e) => {
35            (*stream).error = Some(e);
36            0
37        }
38    }
39}
40
41#[no_mangle]
42pub unsafe extern "C" fn RustOTSStream_Seek(stream: *mut RustOTSStream, position: off_t) -> c_int {
43    match (*stream).wr.seek(SeekFrom::Start(position as u64)) {
44        Ok(_) => 1,
45        _ => 0,
46    }
47}
48
49#[no_mangle]
50pub unsafe extern "C" fn RustOTSStream_Tell(stream: *mut RustOTSStream) -> off_t {
51    match (*stream).wr.seek(SeekFrom::Current(0)) {
52        Err(e) => {
53            // Should be impossible.
54            // FIXME: bad idea to panic when called from C
55            panic!("RustOTSStream_Tell: can't seek: {}", e);
56        }
57        Ok(p) => p as off_t,
58    }
59}
fontsan/ffi.rs

fontsan/
ffi.rs
