1 files changed, 49 insertions, 0 deletions
diff --git a/third_party/rust/alsa/src/io.rs b/third_party/rust/alsa/src/io.rs
new file mode 100644
index 0000000000..f6c3739ec2
--- /dev/null
+++ b/third_party/rust/alsa/src/io.rs
@@ -0,0 +1,49 @@
+use crate::alsa;
+use super::error::*;
+use std::{slice, ptr, fmt};
+
+/// [snd_output_t](http://www.alsa-project.org/alsa-doc/alsa-lib/group___output.html) wrapper
+pub struct Output(*mut alsa::snd_output_t);
+
+unsafe impl Send for Output {}
+
+impl Drop for Output {
+    fn drop(&mut self) { unsafe { alsa::snd_output_close(self.0) }; }
+}
+
+impl Output {
+
+    pub fn buffer_open() -> Result<Output> {
+        let mut q = ptr::null_mut();
+        acheck!(snd_output_buffer_open(&mut q)).map(|_| Output(q))
+    }
+
+    pub fn buffer_string<T, F: FnOnce(&[u8]) -> T>(&self, f: F) -> T {
+        let b = unsafe {
+            let mut q = ptr::null_mut();
+            let s = alsa::snd_output_buffer_string(self.0, &mut q);
+            slice::from_raw_parts(q as *const u8, s as usize)
+        };
+        f(b)
+    }
+}
+
+impl fmt::Debug for Output {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "Output(")?;
+        fmt::Display::fmt(self, f)?;
+        write!(f, ")")
+        /* self.buffer_string(|b| f.write_str(try!(str::from_utf8(b).map_err(|_| fmt::Error)))) */
+    }
+}
+
+impl fmt::Display for Output {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        self.buffer_string(|b| {
+            let s = String::from_utf8_lossy(b);
+            f.write_str(&*s)
+        })
+    }
+}
+
+pub fn output_handle(o: &Output) -> *mut alsa::snd_output_t { o.0 }