use {
crate::{utils::buf::DynamicBuf, xcon::Message},
std::rc::Rc,
uapi::{AssertPacked, OwnedFd, Packed},
};
pub struct Formatter<'a> {
fds: &'a mut Vec<Rc<OwnedFd>>,
buf: &'a mut DynamicBuf,
ext_opcode: u8,
}
impl<'a> Formatter<'a> {
pub fn new(fds: &'a mut Vec<Rc<OwnedFd>>, buf: &'a mut DynamicBuf, ext_opcode: u8) -> Self {
Self {
fds,
buf,
ext_opcode,
}
}
pub fn ext_opcode(&self) -> u8 {
self.ext_opcode
}
pub fn pad(&mut self, pad: usize) {
static BUF: [u8; 8] = [0; 8];
self.buf.extend_from_slice(&BUF[..pad]);
}
pub fn pad_to(&mut self, size: usize) {
static BUF: [u8; 8] = [0; 8];
while self.buf.len() < size {
let len = (size - self.buf.len()).min(8);
self.buf.extend_from_slice(&BUF[..len]);
}
}
pub fn align(&mut self, alignment: usize) {
static BUF: [u8; 8] = [0; 8];
let len = self.buf.len().wrapping_neg() & (alignment - 1);
self.buf.extend_from_slice(&BUF[..len]);
}
pub fn write_packed<T: Packed + ?Sized>(&mut self, t: &T) {
self.buf.extend_from_slice(uapi::as_bytes(t));
}
pub fn write_list<'b, T: Message<'b>>(&mut self, t: &[T]) {
if T::IS_POD {
self.buf
.extend_from_slice(uapi::as_bytes(unsafe { AssertPacked::new(t) }));
} else {
for t in t {
t.serialize(self);
}
}
}
pub fn write_bytes(&mut self, b: &[u8]) {
self.buf.extend_from_slice(b);
}
pub fn write_request_length(&mut self) {
let len: u16 = (self.buf.len() / 4) as u16;
self.buf[2..4].copy_from_slice(&len.to_ne_bytes());
}
pub fn add_fd(&mut self, fd: &Rc<OwnedFd>) {
self.fds.push(fd.clone());
}
}