bincode-orig/src/serde/writer.rs

649 lines
18 KiB
Rust

use std::error::Error;
use std::fmt;
use std::io::Error as IoError;
use std::io::Write;
use std::u32;
use serde_crate as serde;
use byteorder::{BigEndian, WriteBytesExt};
pub type SerializeResult<T> = Result<T, SerializeError>;
/// An error that can be produced during encoding.
#[derive(Debug)]
pub enum SerializeError {
/// An error originating from the underlying `Writer`.
IoError(IoError),
/// An object could not be encoded with the given size limit.
///
/// This error is returned before any bytes are written to the
/// output `Writer`.
SizeLimit,
/// A custom error message
Custom(String)
}
/// An Serializer that encodes values directly into a Writer.
///
/// This struct should not be used often.
/// For most cases, prefer the `encode_into` function.
pub struct Serializer<'a, W: 'a> {
writer: &'a mut W,
}
fn wrap_io(err: IoError) -> SerializeError {
SerializeError::IoError(err)
}
impl serde::ser::Error for SerializeError {
fn custom<T: Into<String>>(msg: T) -> Self {
SerializeError::Custom(msg.into())
}
}
impl fmt::Display for SerializeError {
fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
match *self {
SerializeError::IoError(ref err) => write!(f, "IoError: {}", err),
SerializeError::Custom(ref s) => write!(f, "Custom Error {}", s),
SerializeError::SizeLimit => write!(f, "SizeLimit"),
}
}
}
impl Error for SerializeError {
fn description(&self) -> &str {
match *self {
SerializeError::IoError(ref err) => Error::description(err),
SerializeError::SizeLimit => "the size limit for decoding has been reached",
SerializeError::Custom(_) => "a custom serialization error was reported",
}
}
fn cause(&self) -> Option<&Error> {
match *self {
SerializeError::IoError(ref err) => err.cause(),
SerializeError::SizeLimit => None,
SerializeError::Custom(_) => None,
}
}
}
impl<'a, W: Write> Serializer<'a, W> {
pub fn new(w: &'a mut W) -> Serializer<'a, W> {
Serializer {
writer: w,
}
}
fn add_enum_tag(&mut self, tag: usize) -> SerializeResult<()> {
if tag > u32::MAX as usize {
panic!("Variant tag doesn't fit in a u32")
}
serde::Serializer::serialize_u32(self, tag as u32)
}
}
impl<'a, W: Write> serde::Serializer for Serializer<'a, W> {
type Error = SerializeError;
type SeqState = ();
type TupleState = ();
type TupleStructState = ();
type TupleVariantState = ();
type MapState = ();
type StructState = ();
type StructVariantState = ();
fn serialize_unit(&mut self) -> SerializeResult<()> { Ok(()) }
fn serialize_unit_struct(&mut self, _: &'static str) -> SerializeResult<()> { Ok(()) }
fn serialize_bool(&mut self, v: bool) -> SerializeResult<()> {
self.writer.write_u8(if v {1} else {0}).map_err(wrap_io)
}
fn serialize_u8(&mut self, v: u8) -> SerializeResult<()> {
self.writer.write_u8(v).map_err(wrap_io)
}
fn serialize_u16(&mut self, v: u16) -> SerializeResult<()> {
self.writer.write_u16::<BigEndian>(v).map_err(wrap_io)
}
fn serialize_u32(&mut self, v: u32) -> SerializeResult<()> {
self.writer.write_u32::<BigEndian>(v).map_err(wrap_io)
}
fn serialize_u64(&mut self, v: u64) -> SerializeResult<()> {
self.writer.write_u64::<BigEndian>(v).map_err(wrap_io)
}
fn serialize_usize(&mut self, v: usize) -> SerializeResult<()> {
self.serialize_u64(v as u64)
}
fn serialize_i8(&mut self, v: i8) -> SerializeResult<()> {
self.writer.write_i8(v).map_err(wrap_io)
}
fn serialize_i16(&mut self, v: i16) -> SerializeResult<()> {
self.writer.write_i16::<BigEndian>(v).map_err(wrap_io)
}
fn serialize_i32(&mut self, v: i32) -> SerializeResult<()> {
self.writer.write_i32::<BigEndian>(v).map_err(wrap_io)
}
fn serialize_i64(&mut self, v: i64) -> SerializeResult<()> {
self.writer.write_i64::<BigEndian>(v).map_err(wrap_io)
}
fn serialize_isize(&mut self, v: isize) -> SerializeResult<()> {
self.serialize_i64(v as i64)
}
fn serialize_f32(&mut self, v: f32) -> SerializeResult<()> {
self.writer.write_f32::<BigEndian>(v).map_err(wrap_io)
}
fn serialize_f64(&mut self, v: f64) -> SerializeResult<()> {
self.writer.write_f64::<BigEndian>(v).map_err(wrap_io)
}
fn serialize_str(&mut self, v: &str) -> SerializeResult<()> {
try!(self.serialize_usize(v.len()));
self.writer.write_all(v.as_bytes()).map_err(SerializeError::IoError)
}
fn serialize_char(&mut self, c: char) -> SerializeResult<()> {
self.writer.write_all(encode_utf8(c).as_slice()).map_err(SerializeError::IoError)
}
fn serialize_bytes(&mut self, v: &[u8]) -> SerializeResult<()> {
let mut state = try!(self.serialize_seq(Some(v.len())));
for c in v {
try!(self.serialize_seq_elt(&mut state, c));
}
self.serialize_seq_end(state)
}
fn serialize_none(&mut self) -> SerializeResult<()> {
self.writer.write_u8(0).map_err(wrap_io)
}
fn serialize_some<T>(&mut self, v: T) -> SerializeResult<()>
where T: serde::Serialize,
{
try!(self.writer.write_u8(1).map_err(wrap_io));
v.serialize(self)
}
fn serialize_seq(&mut self, len: Option<usize>) -> SerializeResult<()> {
let len = len.expect("do not know how to serialize a sequence with no length");
self.serialize_usize(len)
}
fn serialize_seq_elt<V>(&mut self, _: &mut (), value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_seq_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_seq_fixed_size(&mut self, len: usize) -> SerializeResult<()> {
self.serialize_seq(Some(len))
}
fn serialize_tuple(&mut self, _len: usize) -> SerializeResult<()> {
Ok(())
}
fn serialize_tuple_elt<V>(&mut self, _: &mut (), value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_tuple_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_tuple_struct(&mut self, _name: &'static str, _len: usize) -> SerializeResult<()> {
Ok(())
}
fn serialize_tuple_struct_elt<V>(&mut self, _: &mut (), value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_tuple_struct_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_tuple_variant(&mut self,
_name: &'static str,
variant_index: usize,
_variant: &'static str,
_len: usize) -> SerializeResult<()>
{
self.add_enum_tag(variant_index)
}
fn serialize_tuple_variant_elt<V>(&mut self, _: &mut (), value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_tuple_variant_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_map(&mut self, len: Option<usize>) -> SerializeResult<()> {
let len = len.expect("do not know how to serialize a map with no length");
self.serialize_usize(len)
}
fn serialize_map_key<K>(&mut self, _: &mut (), key: K) -> SerializeResult<()>
where K: serde::Serialize,
{
key.serialize(self)
}
fn serialize_map_value<V>(&mut self, _: &mut (), value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_map_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_struct(&mut self, _name: &'static str, _len: usize) -> SerializeResult<()> {
Ok(())
}
fn serialize_struct_elt<V>(&mut self, _: &mut (), _key: &'static str, value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_struct_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_struct_variant(&mut self,
_name: &'static str,
variant_index: usize,
_variant: &'static str,
_len: usize) -> SerializeResult<()>
{
self.add_enum_tag(variant_index)
}
fn serialize_struct_variant_elt<V>(&mut self, _: &mut (), _key: &'static str, value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_struct_variant_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_newtype_struct<T>(&mut self,
_name: &'static str,
value: T) -> SerializeResult<()>
where T: serde::ser::Serialize,
{
value.serialize(self)
}
fn serialize_newtype_variant<T>(&mut self,
_name: &'static str,
variant_index: usize,
_variant: &'static str,
value: T) -> SerializeResult<()>
where T: serde::ser::Serialize,
{
try!(self.add_enum_tag(variant_index));
value.serialize(self)
}
fn serialize_unit_variant(&mut self,
_name: &'static str,
variant_index: usize,
_variant: &'static str) -> SerializeResult<()> {
self.add_enum_tag(variant_index)
}
}
pub struct SizeChecker {
pub size_limit: u64,
pub written: u64
}
impl SizeChecker {
pub fn new(limit: u64) -> SizeChecker {
SizeChecker {
size_limit: limit,
written: 0
}
}
fn add_raw(&mut self, size: usize) -> SerializeResult<()> {
self.written += size as u64;
if self.written <= self.size_limit {
Ok(())
} else {
Err(SerializeError::SizeLimit)
}
}
fn add_value<T>(&mut self, t: T) -> SerializeResult<()> {
use std::mem::size_of_val;
self.add_raw(size_of_val(&t))
}
fn add_enum_tag(&mut self, tag: usize) -> SerializeResult<()> {
if tag > u32::MAX as usize {
panic!("Variant tag doesn't fit in a u32")
}
self.add_value(tag as u32)
}
}
impl serde::Serializer for SizeChecker {
type Error = SerializeError;
type SeqState = ();
type TupleState = ();
type TupleStructState = ();
type TupleVariantState = ();
type MapState = ();
type StructState = ();
type StructVariantState = ();
fn serialize_unit(&mut self) -> SerializeResult<()> { Ok(()) }
fn serialize_unit_struct(&mut self, _: &'static str) -> SerializeResult<()> { Ok(()) }
fn serialize_bool(&mut self, _: bool) -> SerializeResult<()> {
self.add_value(0 as u8)
}
fn serialize_u8(&mut self, v: u8) -> SerializeResult<()> {
self.add_value(v)
}
fn serialize_u16(&mut self, v: u16) -> SerializeResult<()> {
self.add_value(v)
}
fn serialize_u32(&mut self, v: u32) -> SerializeResult<()> {
self.add_value(v)
}
fn serialize_u64(&mut self, v: u64) -> SerializeResult<()> {
self.add_value(v)
}
fn serialize_usize(&mut self, v: usize) -> SerializeResult<()> {
self.serialize_u64(v as u64)
}
fn serialize_i8(&mut self, v: i8) -> SerializeResult<()> {
self.add_value(v)
}
fn serialize_i16(&mut self, v: i16) -> SerializeResult<()> {
self.add_value(v)
}
fn serialize_i32(&mut self, v: i32) -> SerializeResult<()> {
self.add_value(v)
}
fn serialize_i64(&mut self, v: i64) -> SerializeResult<()> {
self.add_value(v)
}
fn serialize_isize(&mut self, v: isize) -> SerializeResult<()> {
self.serialize_i64(v as i64)
}
fn serialize_f32(&mut self, v: f32) -> SerializeResult<()> {
self.add_value(v)
}
fn serialize_f64(&mut self, v: f64) -> SerializeResult<()> {
self.add_value(v)
}
fn serialize_str(&mut self, v: &str) -> SerializeResult<()> {
try!(self.add_value(0 as u64));
self.add_raw(v.len())
}
fn serialize_char(&mut self, c: char) -> SerializeResult<()> {
self.add_raw(encode_utf8(c).as_slice().len())
}
fn serialize_bytes(&mut self, v: &[u8]) -> SerializeResult<()> {
let mut state = try!(self.serialize_seq(Some(v.len())));
for c in v {
try!(self.serialize_seq_elt(&mut state, c));
}
self.serialize_seq_end(state)
}
fn serialize_none(&mut self) -> SerializeResult<()> {
self.add_value(0 as u8)
}
fn serialize_some<T>(&mut self, v: T) -> SerializeResult<()>
where T: serde::Serialize,
{
try!(self.add_value(1 as u8));
v.serialize(self)
}
fn serialize_seq(&mut self, len: Option<usize>) -> SerializeResult<()> {
let len = len.expect("do not know how to serialize a sequence with no length");
self.serialize_usize(len)
}
fn serialize_seq_elt<V>(&mut self, _: &mut (), value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_seq_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_seq_fixed_size(&mut self, len: usize) -> SerializeResult<()> {
self.serialize_seq(Some(len))
}
fn serialize_tuple(&mut self, _len: usize) -> SerializeResult<()> {
Ok(())
}
fn serialize_tuple_elt<V>(&mut self, _: &mut (), value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_tuple_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_tuple_struct(&mut self, _name: &'static str, _len: usize) -> SerializeResult<()> {
Ok(())
}
fn serialize_tuple_struct_elt<V>(&mut self, _: &mut (), value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_tuple_struct_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_tuple_variant(&mut self,
_name: &'static str,
variant_index: usize,
_variant: &'static str,
_len: usize) -> SerializeResult<()>
{
self.add_enum_tag(variant_index)
}
fn serialize_tuple_variant_elt<V>(&mut self, _: &mut (), value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_tuple_variant_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_map(&mut self, len: Option<usize>) -> SerializeResult<()>
{
let len = len.expect("do not know how to serialize a map with no length");
self.serialize_usize(len)
}
fn serialize_map_key<K>(&mut self, _: &mut (), key: K) -> SerializeResult<()>
where K: serde::Serialize,
{
key.serialize(self)
}
fn serialize_map_value<V>(&mut self, _: &mut (), value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_map_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_struct(&mut self, _name: &'static str, _len: usize) -> SerializeResult<()> {
Ok(())
}
fn serialize_struct_elt<V>(&mut self, _: &mut (), _key: &'static str, value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_struct_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_struct_variant(&mut self,
_name: &'static str,
variant_index: usize,
_variant: &'static str,
_len: usize) -> SerializeResult<()>
{
self.add_enum_tag(variant_index)
}
fn serialize_struct_variant_elt<V>(&mut self, _: &mut (), _field: &'static str, value: V) -> SerializeResult<()>
where V: serde::Serialize,
{
value.serialize(self)
}
fn serialize_struct_variant_end(&mut self, _: ()) -> SerializeResult<()> {
Ok(())
}
fn serialize_newtype_struct<V: serde::Serialize>(&mut self, _name: &'static str, v: V) -> SerializeResult<()> {
v.serialize(self)
}
fn serialize_unit_variant(&mut self,
_name: &'static str,
variant_index: usize,
_variant: &'static str) -> SerializeResult<()> {
self.add_enum_tag(variant_index)
}
fn serialize_newtype_variant<V: serde::Serialize>(&mut self,
_name: &'static str,
variant_index: usize,
_variant: &'static str,
value: V) -> SerializeResult<()>
{
try!(self.add_enum_tag(variant_index));
value.serialize(self)
}
}
const TAG_CONT: u8 = 0b1000_0000;
const TAG_TWO_B: u8 = 0b1100_0000;
const TAG_THREE_B: u8 = 0b1110_0000;
const TAG_FOUR_B: u8 = 0b1111_0000;
const MAX_ONE_B: u32 = 0x80;
const MAX_TWO_B: u32 = 0x800;
const MAX_THREE_B: u32 = 0x10000;
fn encode_utf8(c: char) -> EncodeUtf8 {
let code = c as u32;
let mut buf = [0; 4];
let pos = if code < MAX_ONE_B {
buf[3] = code as u8;
3
} else if code < MAX_TWO_B {
buf[2] = (code >> 6 & 0x1F) as u8 | TAG_TWO_B;
buf[3] = (code & 0x3F) as u8 | TAG_CONT;
2
} else if code < MAX_THREE_B {
buf[1] = (code >> 12 & 0x0F) as u8 | TAG_THREE_B;
buf[2] = (code >> 6 & 0x3F) as u8 | TAG_CONT;
buf[3] = (code & 0x3F) as u8 | TAG_CONT;
1
} else {
buf[0] = (code >> 18 & 0x07) as u8 | TAG_FOUR_B;
buf[1] = (code >> 12 & 0x3F) as u8 | TAG_CONT;
buf[2] = (code >> 6 & 0x3F) as u8 | TAG_CONT;
buf[3] = (code & 0x3F) as u8 | TAG_CONT;
0
};
EncodeUtf8 { buf: buf, pos: pos }
}
struct EncodeUtf8 {
buf: [u8; 4],
pos: usize,
}
impl EncodeUtf8 {
fn as_slice(&self) -> &[u8] {
&self.buf[self.pos..]
}
}