add libio (to be shared between runtime and satman)

Reviewed-on: M-Labs/artiq-zynq#138
Co-authored-by: mwojcik <mw@m-labs.hk>
Co-committed-by: mwojcik <mw@m-labs.hk>

src/libio/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+authors = ["M-Labs"]
+name = "io"
+version = "0.0.0"
+
+[lib]
+name = "io"
+path = "lib.rs"
+
+[dependencies]
+core_io = { version = "0.1", features = ["collections"] }
+byteorder = { version = "1.0", default-features = false, optional = true }
+
+libsupport_zynq = { default-features = false, features = ["alloc_core"], git = "https://git.m-labs.hk/M-Labs/zynq-rs.git" }
+
+[features]
+alloc = []

src/libio/cursor.rs

@@ -0,0 +1,81 @@
+use core_io::{Read, Write, Error as IoError};
+
+#[derive(Debug, Clone)]
+pub struct Cursor<T> {
+    inner: T,
+    pos:   usize
+}
+
+impl<T> Cursor<T> {
+    #[inline]
+    pub fn new(inner: T) -> Cursor<T> {
+        Cursor { inner, pos: 0 }
+    }
+
+    #[inline]
+    pub fn into_inner(self) -> T {
+        self.inner
+    }
+
+    #[inline]
+    pub fn get_ref(&self) -> &T {
+        &self.inner
+    }
+
+    #[inline]
+    pub fn get_mut(&mut self) -> &mut T {
+        &mut self.inner
+    }
+
+    #[inline]
+    pub fn position(&self) -> usize {
+        self.pos
+    }
+
+    #[inline]
+    pub fn set_position(&mut self, pos: usize) {
+        self.pos = pos
+    }
+}
+
+impl<T: AsRef<[u8]>> Read for Cursor<T> {
+
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize, IoError> {
+        let data = &self.inner.as_ref()[self.pos..];
+        let len = buf.len().min(data.len());
+        buf[..len].copy_from_slice(&data[..len]);
+        self.pos += len;
+        Ok(len)
+    }
+}
+
+impl Write for Cursor<&mut [u8]> {
+
+    fn write(&mut self, buf: &[u8]) -> Result<usize, IoError> {
+        let data = &mut self.inner[self.pos..];
+        let len  = buf.len().min(data.len());
+        data[..len].copy_from_slice(&buf[..len]);
+        self.pos += len;
+        Ok(len)
+    }
+
+    #[inline]
+    fn flush(&mut self) -> Result<(), IoError> {
+        Ok(())
+    }
+}
+
+#[cfg(feature = "alloc")]
+impl Write for Cursor<::alloc::Vec<u8>> {
+
+    #[inline]
+    fn write(&mut self, buf: &[u8]) -> Result<usize, IoError> {
+        self.inner.extend_from_slice(buf);
+        Ok(buf.len())
+    }
+
+    #[inline]
+    fn flush(&mut self) -> Result<(), IoError> {
+        Ok(())
+    }
+}

src/libio/lib.rs

@@ -0,0 +1,22 @@
+#![no_std]
+#![feature(never_type)]
+#![cfg_attr(feature = "alloc", feature(alloc))]
+
+extern crate alloc;
+extern crate core_io;
+
+#[cfg(feature = "alloc")]
+#[macro_use]
+use alloc;
+#[cfg(feature = "byteorder")]
+extern crate byteorder;
+
+pub mod cursor;
+#[cfg(feature = "byteorder")]
+pub mod proto;
+
+pub use cursor::Cursor;
+#[cfg(feature = "byteorder")]
+pub use proto::{ProtoRead, ProtoWrite};
+#[cfg(all(feature = "byteorder", feature = "alloc"))]
+pub use proto::ReadStringError;

src/libio/proto.rs

@@ -0,0 +1,158 @@
+use core::str::Utf8Error;
+use byteorder::{ByteOrder, NativeEndian};
+use alloc::vec;
+use alloc::string::String;
+
+use core_io::{Read, Write, Error as IoError};
+
+#[allow(dead_code)]
+#[derive(Debug, Clone, PartialEq)]
+pub enum ReadStringError<T> {
+    Utf8(Utf8Error),
+    Other(T)
+}
+
+pub trait ProtoRead {
+    type ReadError;
+
+    fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Self::ReadError>;
+
+    #[inline]
+    fn read_u8(&mut self) -> Result<u8, Self::ReadError> {
+        let mut bytes = [0; 1];
+        self.read_exact(&mut bytes)?;
+        Ok(bytes[0])
+    }
+
+    #[inline]
+    fn read_u16(&mut self) -> Result<u16, Self::ReadError> {
+        let mut bytes = [0; 2];
+        self.read_exact(&mut bytes)?;
+        Ok(NativeEndian::read_u16(&bytes))
+    }
+
+    #[inline]
+    fn read_u32(&mut self) -> Result<u32, Self::ReadError> {
+        let mut bytes = [0; 4];
+        self.read_exact(&mut bytes)?;
+        Ok(NativeEndian::read_u32(&bytes))
+    }
+
+    #[inline]
+    fn read_u64(&mut self) -> Result<u64, Self::ReadError> {
+        let mut bytes = [0; 8];
+        self.read_exact(&mut bytes)?;
+        Ok(NativeEndian::read_u64(&bytes))
+    }
+
+    #[inline]
+    fn read_bool(&mut self) -> Result<bool, Self::ReadError> {
+        Ok(self.read_u8()? != 0)
+    }
+
+    #[inline]
+    fn read_bytes(&mut self) -> Result<::alloc::vec::Vec<u8>, Self::ReadError> {
+        let length = self.read_u32()?;
+        let mut value = vec![0; length as usize];
+        self.read_exact(&mut value)?;
+        Ok(value)
+    }
+
+    #[inline]
+    fn read_string(&mut self) -> Result<::alloc::string::String, ReadStringError<Self::ReadError>> {
+        let bytes = self.read_bytes().map_err(ReadStringError::Other)?;
+        String::from_utf8(bytes).map_err(|err| ReadStringError::Utf8(err.utf8_error()))
+    }
+}
+
+pub trait ProtoWrite {
+    type WriteError;
+
+    fn write_all(&mut self, buf: &[u8]) -> Result<(), Self::WriteError>;
+
+    #[inline]
+    fn write_u8(&mut self, value: u8) -> Result<(), Self::WriteError> {
+        let bytes = [value; 1];
+        self.write_all(&bytes)
+    }
+
+    #[inline]
+    fn write_i8(&mut self, value: i8) -> Result<(), Self::WriteError> {
+        let bytes = [value as u8; 1];
+        self.write_all(&bytes)
+    }
+
+    #[inline]
+    fn write_u16(&mut self, value: u16) -> Result<(), Self::WriteError> {
+        let mut bytes = [0; 2];
+        NativeEndian::write_u16(&mut bytes, value);
+        self.write_all(&bytes)
+    }
+
+    #[inline]
+    fn write_i16(&mut self, value: i16) -> Result<(), Self::WriteError> {
+        let mut bytes = [0; 2];
+        NativeEndian::write_i16(&mut bytes, value);
+        self.write_all(&bytes)
+    }
+
+    #[inline]
+    fn write_u32(&mut self, value: u32) -> Result<(), Self::WriteError> {
+        let mut bytes = [0; 4];
+        NativeEndian::write_u32(&mut bytes, value);
+        self.write_all(&bytes)
+    }
+
+    #[inline]
+    fn write_i32(&mut self, value: i32) -> Result<(), Self::WriteError> {
+        let mut bytes = [0; 4];
+        NativeEndian::write_i32(&mut bytes, value);
+        self.write_all(&bytes)
+    }
+
+    #[inline]
+    fn write_u64(&mut self, value: u64) -> Result<(), Self::WriteError> {
+        let mut bytes = [0; 8];
+        NativeEndian::write_u64(&mut bytes, value);
+        self.write_all(&bytes)
+    }
+
+    #[inline]
+    fn write_i64(&mut self, value: i64) -> Result<(), Self::WriteError> {
+        let mut bytes = [0; 8];
+        NativeEndian::write_i64(&mut bytes, value);
+        self.write_all(&bytes)
+    }
+
+    #[inline]
+    fn write_bool(&mut self, value: bool) -> Result<(), Self::WriteError> {
+        self.write_u8(value as u8)
+    }
+
+    #[inline]
+    fn write_bytes(&mut self, value: &[u8]) -> Result<(), Self::WriteError> {
+        self.write_u32(value.len() as u32)?;
+        self.write_all(value)
+    }
+
+    #[inline]
+    fn write_string(&mut self, value: &str) -> Result<(), Self::WriteError> {
+        self.write_bytes(value.as_bytes())
+    }
+}
+
+impl<T> ProtoRead for T where T: Read + ?Sized {
+    type ReadError = IoError;
+
+    fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), Self::ReadError> {
+        T::read_exact(self, buf)
+    }
+}
+
+impl<T> ProtoWrite for T where T: Write + ?Sized {
+    type WriteError = IoError;
+
+    fn write_all(&mut self, buf: &[u8]) -> Result<(), Self::WriteError> {
+        T::write_all(self, buf)
+    }
+}