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use crate::fs::File;
use crate::mm::UserBuffer;
pub struct Zero;
pub struct Null;
impl File for Zero {
fn readable(&self) -> bool {
true
}
fn writable(&self) -> bool {
true
}
fn read(&self, mut buf: UserBuffer) -> usize {
buf.clear();
return buf.len();
}
fn write(&self, buf: UserBuffer) -> usize {
return buf.len();
}
}
impl File for Null {
fn readable(&self) -> bool {
true
}
fn writable(&self) -> bool {
true
}
fn read(&self, _buf: UserBuffer) -> usize {
return 0;
}
fn write(&self, buf: UserBuffer) -> usize {
return buf.len();
}
}