firmware: fix satman build.

artiq/firmware/Cargo.lock

@@ -17,6 +17,8 @@ dependencies = [
  "build_misoc 0.0.0",
  "byteorder 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "crc 1.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "failure 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "failure_derive 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "io 0.0.0",
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "proto_artiq 0.0.0",
@@ -176,7 +178,7 @@ dependencies = [
 [[package]]
 name = "log_buffer"
 version = "1.2.0"
-source = "git+https://github.com/whitequark/rust-log_buffer?rev=rust-1.25#ff84e565d9954d5864d60aec12b9e1381505d72a"
+source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "logger_artiq"
@@ -184,7 +186,7 @@ version = "0.0.0"
 dependencies = [
  "board_misoc 0.0.0",
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "log_buffer 1.2.0 (git+https://github.com/whitequark/rust-log_buffer?rev=rust-1.25)",
+ "log_buffer 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -340,7 +342,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum libc 0.2.40 (registry+https://github.com/rust-lang/crates.io-index)" = "6fd41f331ac7c5b8ac259b8bf82c75c0fb2e469bbf37d2becbba9a6a2221965b"
 "checksum log 0.3.9 (registry+https://github.com/rust-lang/crates.io-index)" = "e19e8d5c34a3e0e2223db8e060f9e8264aeeb5c5fc64a4ee9965c062211c024b"
 "checksum log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "89f010e843f2b1a31dbd316b3b8d443758bc634bed37aabade59c686d644e0a2"
-"checksum log_buffer 1.2.0 (git+https://github.com/whitequark/rust-log_buffer?rev=rust-1.25)" = "<none>"
+"checksum log_buffer 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f033173c9486b7fe97a79c895c0a3483ae395ab6744c985d10078950e2492419"
 "checksum managed 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "43e2737ecabe4ae36a68061398bf27d2bfd0763f4c3c837a398478459494c4b7"
 "checksum managed 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)" = "5a31885241e61ba264d780d2e6686e7e59561c947b4581470364eb3e10102d86"
 "checksum quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e920b65c65f10b2ae65c831a81a073a89edd28c7cce89475bff467ab4167a"

artiq/firmware/libboard_artiq/Cargo.toml

@@ -13,6 +13,8 @@ build_misoc = { path = "../libbuild_misoc" }
 build_artiq = { path = "../libbuild_artiq" }
 
 [dependencies]
+failure = { version = "0.1", default-features = false }
+failure_derive = { version = "0.1", default-features = false }
 bitflags = "1.0"
 byteorder = { version = "1.0", default-features = false }
 crc = { version = "1.7", default-features = false }

artiq/firmware/libboard_artiq/drtioaux.rs

@@ -1,43 +1,36 @@
-use core::{slice, fmt, result};
+use core::slice;
 use crc;
 
-use io::{Cursor, Error as IoError};
+use io::{ProtoRead, ProtoWrite, Cursor, Error as IoError};
-use io::proto::{ProtoRead, ProtoWrite};
 use board_misoc::{csr::DRTIO, mem::DRTIO_AUX, clock};
+use proto_artiq::drtioaux_proto::Error as ProtocolError;
 
 pub use proto_artiq::drtioaux_proto::Packet;
 
-pub type Result<T> = result::Result<T, Error>;
+// this is parametric over T because there's no impl Fail for !.
-
+#[derive(Fail, Debug)]
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Error<T> {
-pub enum Error {
+    #[fail(display = "packet CRC failed")]
     CorruptedPacket,
+    #[fail(display = "timed out waiting for data")]
     TimedOut,
+    #[fail(display = "invalid node number")]
     NoRoute,
+    #[fail(display = "gateware reported error")]
     GatewareError,
-    Io(IoError<!>)
+    #[fail(display = "protocol error: {}", _0)]
+    Protocol(#[cause] ProtocolError<T>)
 }
 
-impl fmt::Display for Error {
+impl<T> From<ProtocolError<T>> for Error<T> {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn from(value: ProtocolError<T>) -> Error<T> {
-        match self {
+        Error::Protocol(value)
-            &Error::CorruptedPacket =>
-                write!(f, "packet CRC failed"),
-            &Error::TimedOut =>
-                write!(f, "timed out waiting for data"),
-            &Error::NoRoute =>
-                write!(f, "invalid node number"),
-            &Error::GatewareError =>
-                write!(f, "gateware reported error"),
-            &Error::Io(ref io) =>
-                write!(f, "I/O error ({})", io)
-        }
     }
 }
 
-impl From<IoError<!>> for Error {
+impl<T> From<IoError<T>> for Error<T> {
-    fn from(value: IoError<!>) -> Error {
+    fn from(value: IoError<T>) -> Error<T> {
-        Error::Io(value)
+        Error::Protocol(ProtocolError::Io(value))
     }
 }
 
@@ -63,8 +56,8 @@ fn has_rx_error(linkno: u8) -> bool {
     }
 }
 
-fn receive<F, T>(linkno: u8, f: F) -> Result<Option<T>>
+fn receive<F, T>(linkno: u8, f: F) -> Result<Option<T>, Error<!>>
-    where F: FnOnce(&[u8]) -> Result<T>
+    where F: FnOnce(&[u8]) -> Result<T, Error<!>>
 {
     let linkidx = linkno as usize;
     unsafe {
@@ -80,14 +73,14 @@ fn receive<F, T>(linkno: u8, f: F) -> Result<Option<T>>
     }
 }
 
-pub fn recv_link(linkno: u8) -> Result<Option<Packet>> {
+pub fn recv_link(linkno: u8) -> Result<Option<Packet>, Error<!>> {
     if has_rx_error(linkno) {
         return Err(Error::GatewareError)
     }
 
     receive(linkno, |buffer| {
         if buffer.len() < 8 {
-            return Err(Error::Io(IoError::UnexpectedEof))
+            return Err(IoError::UnexpectedEnd.into())
         }
 
         let mut reader = Cursor::new(buffer);
@@ -104,7 +97,7 @@ pub fn recv_link(linkno: u8) -> Result<Option<Packet>> {
     })
 }
 
-pub fn recv_timeout_link(linkno: u8, timeout_ms: Option<u64>) -> Result<Packet> {
+pub fn recv_timeout_link(linkno: u8, timeout_ms: Option<u64>) -> Result<Packet, Error<!>> {
     let timeout_ms = timeout_ms.unwrap_or(10);
     let limit = clock::get_ms() + timeout_ms;
     while clock::get_ms() < limit {
@@ -116,8 +109,8 @@ pub fn recv_timeout_link(linkno: u8, timeout_ms: Option<u64>) -> Result<Packet>
     Err(Error::TimedOut)
 }
 
-fn transmit<F>(linkno: u8, f: F) -> Result<()>
+fn transmit<F>(linkno: u8, f: F) -> Result<(), Error<!>>
-    where F: FnOnce(&mut [u8]) -> Result<usize>
+    where F: FnOnce(&mut [u8]) -> Result<usize, Error<!>>
 {
     let linkno = linkno as usize;
     unsafe {
@@ -131,7 +124,7 @@ fn transmit<F>(linkno: u8, f: F) -> Result<()>
     }
 }
 
-pub fn send_link(linkno: u8, packet: &Packet) -> Result<()> {
+pub fn send_link(linkno: u8, packet: &Packet) -> Result<(), Error<!>> {
     transmit(linkno, |buffer| {
         let mut writer = Cursor::new(buffer);
 
@@ -152,24 +145,24 @@ pub fn send_link(linkno: u8, packet: &Packet) -> Result<()> {
 }
 
 // TODO: routing
-fn get_linkno(nodeno: u8) -> Result<u8> {
+fn get_linkno(nodeno: u8) -> Result<u8, Error<!>> {
     if nodeno == 0 || nodeno as usize > DRTIO.len() {
         return Err(Error::NoRoute)
     }
     Ok(nodeno - 1)
 }
 
-pub fn recv(nodeno: u8) -> Result<Option<Packet>> {
+pub fn recv(nodeno: u8) -> Result<Option<Packet>, Error<!>> {
     let linkno = get_linkno(nodeno)?;
     recv_link(linkno)
 }
 
-pub fn recv_timeout(nodeno: u8, timeout_ms: Option<u64>) -> Result<Packet> {
+pub fn recv_timeout(nodeno: u8, timeout_ms: Option<u64>) -> Result<Packet, Error<!>> {
     let linkno = get_linkno(nodeno)?;
     recv_timeout_link(linkno, timeout_ms)
 }
 
-pub fn send(nodeno: u8, packet: &Packet) -> Result<()> {
+pub fn send(nodeno: u8, packet: &Packet) -> Result<(), Error<!>> {
     let linkno = get_linkno(nodeno)?;
     send_link(linkno, packet)
 }

artiq/firmware/libboard_artiq/lib.rs

@@ -1,6 +1,10 @@
 #![feature(asm, lang_items, never_type)]
 #![no_std]
 
+extern crate failure;
+#[cfg(has_drtio)]
+#[macro_use]
+extern crate failure_derive;
 #[macro_use]
 extern crate bitflags;
 extern crate byteorder;

artiq/firmware/satman/main.rs

@@ -26,7 +26,7 @@ fn drtio_reset_phy(reset: bool) {
     }
 }
 
-fn process_aux_packet(packet: drtioaux::Packet) -> drtioaux::Result<()> {
+fn process_aux_packet(packet: drtioaux::Packet) -> Result<(), drtioaux::Error<!>> {
     // In the code below, *_chan_sel_write takes an u8 if there are fewer than 256 channels,
     // and u16 otherwise; hence the `as _` conversion.
     match packet {