Impl Write and Read for std::io::{Write, Read}

src/elements/mod.rs

@@ -255,33 +255,23 @@ pub fn serialize<T: Serialize>(val: T) -> Result<Vec<u8>, T::Error> {
 	Ok(buf)
 }
 
-/// Deserialize module from file.
+/// Deserialize module from the file.
 #[cfg(feature = "std")]
 pub fn deserialize_file<P: AsRef<::std::path::Path>>(p: P) -> Result<Module, Error> {
-	use std::io::Read;
-
-	let mut contents = Vec::new();
-
-	::std::fs::File::open(p)
-		.and_then(|mut f| f.read_to_end(&mut contents))
+	let mut f = ::std::fs::File::open(p)
 		.map_err(|e| Error::HeapOther(format!("Can't read from the file: {:?}", e)))?;
 
-	deserialize_buffer(&contents)
+	Module::deserialize(&mut f)
 }
 
 /// Serialize module to the file
 #[cfg(feature = "std")]
 pub fn serialize_to_file<P: AsRef<::std::path::Path>>(p: P, module: Module) -> Result<(), Error> {
-	use std::io::Write;
-
 	let mut io = ::std::fs::File::create(p)
-		.map_err(|e| Error::HeapOther(format!("Can't create the file: {:?}", e)))?;
-	let mut buf = Vec::new();
-
-	module.serialize(&mut buf)?;
-
-	io.write_all(&buf)
-		.map_err(|e| Error::HeapOther(format!("Can't write to the file: {:?}", e)))?;
+		.map_err(|e|
+			Error::HeapOther(format!("Can't create the file: {:?}", e))
+		)?;
 
+	module.serialize(&mut io)?;
 	Ok(())
 }

src/io.rs

@@ -3,10 +3,8 @@
 //! Basically it just a replacement for the std::io that is usable from
 //! the `no_std` environment.
 
-use std::vec::Vec;
-
 /// IO specific error.
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Debug)]
 pub enum Error {
 	/// Some unexpected data left in the buffer after reading all data.
 	TrailingData,
@@ -16,6 +14,9 @@ pub enum Error {
 
 	/// Invalid data is encountered.
 	InvalidData,
+
+	#[cfg(feature = "std")]
+	IoError(::std::io::Error),
 }
 
 /// IO specific Result.
@@ -35,13 +36,6 @@ pub trait Read {
 	fn read(&mut self, buf: &mut [u8]) -> Result<()>;
 }
 
-impl Write for Vec<u8> {
-	fn write(&mut self, buf: &[u8]) -> Result<()> {
-		self.extend(buf);
-		Ok(())
-	}
-}
-
 /// Reader that saves the last position.
 pub struct Cursor<T> {
 	inner: T,
@@ -75,6 +69,29 @@ impl<T: AsRef<[u8]>> Read for Cursor<T> {
 	}
 }
 
+#[cfg(not(feature = "std"))]
+impl Write for ::std::vec::Vec<u8> {
+	fn write(&mut self, buf: &[u8]) -> Result<()> {
+		self.extend(buf);
+		Ok(())
+	}
+}
+
+#[cfg(feature = "std")]
+impl<T: ::std::io::Read> Read for T {
+	fn read(&mut self, buf: &mut [u8]) -> Result<()> {
+		self.read_exact(buf)
+			.map_err(Error::IoError)
+	}
+}
+
+#[cfg(feature = "std")]
+impl<T: ::std::io::Write> Write for T {
+	fn write(&mut self, buf: &[u8]) -> Result<()> {
+		self.write_all(buf).map_err(Error::IoError)
+	}
+}
+
 #[cfg(test)]
 mod tests {
 	use super::*;