lix/nix-rust/src/foreign.rs
2019-11-26 22:07:28 +01:00

15 lines
426 B
Rust

/// A wrapper around Nix's Source class that provides the Read trait.
#[repr(C)]
pub struct Source {
fun: extern "C" fn(this: *mut libc::c_void, data: &mut [u8]) -> usize,
this: *mut libc::c_void,
}
impl std::io::Read for Source {
fn read(&mut self, buf: &mut [u8]) -> std::result::Result<usize, std::io::Error> {
let n = (self.fun)(self.this, buf);
assert!(n <= buf.len());
Ok(n)
}
}