autocommit 2022-01-02 15:13:33 CET

src/utils/buffd/wl_formatter.rs

@@ -0,0 +1,78 @@
+use crate::objects::ObjectId;
+use crate::utils::buffd::buf_out::{BufFdOut, MsgFds};
+use std::mem;
+use std::mem::MaybeUninit;
+use uapi::OwnedFd;
+
+pub struct WlFormatter<'a> {
+    buf: &'a mut BufFdOut,
+    pos: usize,
+    fds: Vec<OwnedFd>,
+}
+
+impl<'a> WlFormatter<'a> {
+    pub fn new(buf: &'a mut BufFdOut) -> Self {
+        Self {
+            pos: buf.out_pos,
+            buf,
+            fds: vec![],
+        }
+    }
+
+    pub fn int(&mut self, int: i32) -> &mut Self {
+        self.buf.write(uapi::as_maybe_uninit_bytes(&int));
+        self
+    }
+
+    pub fn uint(&mut self, int: u32) -> &mut Self {
+        self.buf.write(uapi::as_maybe_uninit_bytes(&int));
+        self
+    }
+
+    pub fn fixed(&mut self, fixed: f64) -> &mut Self {
+        let int = (fixed * 256.0) as i32;
+        self.buf.write(uapi::as_maybe_uninit_bytes(&int));
+        self
+    }
+
+    pub fn string(&mut self, s: &str) -> &mut Self {
+        let len = s.len() + 1;
+        let cap = (len + 3) & !3;
+        self.uint(len as u32);
+        self.buf.write(uapi::as_maybe_uninit_bytes(s.as_bytes()));
+        let none = [MaybeUninit::new(0); 4];
+        self.buf.write(&none[..cap - len + 1]);
+        self
+    }
+
+    pub fn fd(&mut self, fd: OwnedFd) -> &mut Self {
+        self.fds.push(fd);
+        self
+    }
+
+    pub fn object(&mut self, obj: ObjectId) -> &mut Self {
+        self.uint(obj.raw())
+    }
+
+    pub fn header(&mut self, obj: ObjectId, event: u32) -> &mut Self {
+        self.object(obj).uint(event)
+    }
+}
+
+impl<'a> Drop for WlFormatter<'a> {
+    fn drop(&mut self) {
+        assert!(self.buf.out_pos - self.pos >= 8);
+        assert_eq!(self.pos % 4, 0);
+        unsafe {
+            let second_ptr = (self.buf.out_buf as *mut u8).add(self.pos + 4) as *mut u32;
+            let len = ((self.buf.out_pos - self.pos) as u32) << 16;
+            *second_ptr |= len;
+        }
+        if self.fds.len() > 0 {
+            self.buf.fds.push_back(MsgFds {
+                pos: self.pos,
+                fds: mem::take(&mut self.fds),
+            })
+        }
+    }
+}