autocommit 2022-03-22 23:24:17 CET

src/xcon/formatter.rs

@@ -0,0 +1,62 @@
+use crate::xcon::Message;
+use std::rc::Rc;
+use uapi::{AssertPacked, OwnedFd, Packed};
+
+pub struct Formatter<'a> {
+    fds: &'a mut Vec<Rc<OwnedFd>>,
+    buf: &'a mut Vec<u8>,
+    ext_opcode: u8,
+}
+
+impl<'a> Formatter<'a> {
+    pub fn new(fds: &'a mut Vec<Rc<OwnedFd>>, buf: &'a mut Vec<u8>, 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 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());
+    }
+}