| //! Generic MessagePack deserialization. |
| |
| use std::error; |
| use std::fmt::{self, Display, Formatter}; |
| use std::io::{self, Cursor, ErrorKind, Read}; |
| use std::str::{self, Utf8Error}; |
| |
| use byteorder::{self, ReadBytesExt}; |
| |
| use serde; |
| use serde::de::{self, Deserialize, DeserializeOwned, DeserializeSeed, Visitor}; |
| |
| use rmp; |
| use rmp::Marker; |
| use rmp::decode::{self, MarkerReadError, DecodeStringError, ValueReadError, NumValueReadError}; |
| |
| use crate::MSGPACK_EXT_STRUCT_NAME; |
| |
| /// Enum representing errors that can occur while decoding MessagePack data. |
| #[derive(Debug)] |
| pub enum Error { |
| /// The enclosed I/O error occurred while trying to read a MessagePack |
| /// marker. |
| InvalidMarkerRead(io::Error), |
| /// The enclosed I/O error occurred while trying to read the encoded |
| /// MessagePack data. |
| InvalidDataRead(io::Error), |
| /// A mismatch occurred between the decoded and expected value types. |
| TypeMismatch(Marker), |
| /// A numeric cast failed due to an out-of-range error. |
| OutOfRange, |
| /// A decoded array did not have the enclosed expected length. |
| LengthMismatch(u32), |
| /// An otherwise uncategorized error occurred. See the enclosed `String` for |
| /// details. |
| Uncategorized(String), |
| /// A general error occurred while deserializing the expected type. See the |
| /// enclosed `String` for details. |
| Syntax(String), |
| /// An encoded string could not be parsed as UTF-8. |
| Utf8Error(Utf8Error), |
| /// The depth limit was exceeded; not currently used. |
| DepthLimitExceeded, |
| } |
| |
| impl error::Error for Error { |
| fn description(&self) -> &str { |
| "error while decoding value" |
| } |
| |
| fn cause(&self) -> Option<&dyn error::Error> { |
| match *self { |
| Error::TypeMismatch(..) => None, |
| Error::InvalidMarkerRead(ref err) => Some(err), |
| Error::InvalidDataRead(ref err) => Some(err), |
| Error::LengthMismatch(..) => None, |
| Error::OutOfRange => None, |
| Error::Uncategorized(..) => None, |
| Error::Syntax(..) => None, |
| Error::Utf8Error(ref err) => Some(err), |
| Error::DepthLimitExceeded => None, |
| } |
| } |
| } |
| |
| impl de::Error for Error { |
| fn custom<T: Display>(msg: T) -> Self { |
| Error::Syntax(msg.to_string()) |
| } |
| } |
| |
| impl Display for Error { |
| fn fmt(&self, fmt: &mut Formatter<'_>) -> Result<(), fmt::Error> { |
| match *self { |
| Error::InvalidMarkerRead(ref err) => write!(fmt, "IO error while reading marker: {}", err), |
| Error::InvalidDataRead(ref err) => write!(fmt, "IO error while reading data: {}", err), |
| Error::TypeMismatch(ref actual_marker) => { |
| write!(fmt, "wrong msgpack marker {:?}", actual_marker) |
| } |
| Error::OutOfRange => fmt.write_str("numeric cast found out of range"), |
| Error::LengthMismatch(expected_length) => write!( |
| fmt, |
| "array had incorrect length, expected {}", |
| expected_length |
| ), |
| Error::Uncategorized(ref msg) => write!(fmt, "uncategorized error: {}", msg), |
| Error::Syntax(ref msg) => fmt.write_str(msg), |
| Error::Utf8Error(ref err) => write!(fmt, "string found to be invalid utf8: {}", err), |
| Error::DepthLimitExceeded => fmt.write_str("depth limit exceeded"), |
| } |
| } |
| } |
| |
| impl From<MarkerReadError> for Error { |
| fn from(err: MarkerReadError) -> Error { |
| match err { |
| MarkerReadError(err) => Error::InvalidMarkerRead(err), |
| } |
| } |
| } |
| |
| impl From<Utf8Error> for Error { |
| fn from(err: Utf8Error) -> Error { |
| Error::Utf8Error(err) |
| } |
| } |
| |
| impl From<ValueReadError> for Error { |
| fn from(err: ValueReadError) -> Error { |
| match err { |
| ValueReadError::TypeMismatch(marker) => Error::TypeMismatch(marker), |
| ValueReadError::InvalidMarkerRead(err) => Error::InvalidMarkerRead(err), |
| ValueReadError::InvalidDataRead(err) => Error::InvalidDataRead(err), |
| } |
| } |
| } |
| |
| impl From<NumValueReadError> for Error { |
| fn from(err: NumValueReadError) -> Error { |
| match err { |
| NumValueReadError::TypeMismatch(marker) => Error::TypeMismatch(marker), |
| NumValueReadError::InvalidMarkerRead(err) => Error::InvalidMarkerRead(err), |
| NumValueReadError::InvalidDataRead(err) => Error::InvalidDataRead(err), |
| NumValueReadError::OutOfRange => Error::OutOfRange, |
| } |
| } |
| } |
| |
| impl<'a> From<DecodeStringError<'a>> for Error { |
| fn from(err: DecodeStringError<'_>) -> Error { |
| match err { |
| DecodeStringError::InvalidMarkerRead(err) => Error::InvalidMarkerRead(err), |
| DecodeStringError::InvalidDataRead(err) => Error::InvalidDataRead(err), |
| DecodeStringError::TypeMismatch(marker) => Error::TypeMismatch(marker), |
| DecodeStringError::BufferSizeTooSmall(..) => Error::Uncategorized("BufferSizeTooSmall".to_string()), |
| DecodeStringError::InvalidUtf8(..) => Error::Uncategorized("InvalidUtf8".to_string()), |
| } |
| } |
| } |
| |
| /// A Deserializer that reads bytes from a buffer. |
| /// |
| /// # Note |
| /// |
| /// All instances of `ErrorKind::Interrupted` are handled by this function and the underlying |
| /// operation is retried. |
| #[derive(Debug)] |
| pub struct Deserializer<R> { |
| rd: R, |
| marker: Option<Marker>, |
| depth: usize, |
| } |
| |
| impl<R: Read> Deserializer<ReadReader<R>> { |
| #[doc(hidden)] |
| #[deprecated(note="use `Deserializer::new` instead")] |
| pub fn from_read(rd: R) -> Self { |
| Self::new(rd) |
| } |
| |
| /// Constructs a new `Deserializer` by consuming the given reader. |
| pub fn new(rd: R) -> Self { |
| Self { |
| rd: ReadReader::new(rd), |
| // Cached marker in case of deserializing optional values. |
| marker: None, |
| depth: 1024, |
| } |
| } |
| |
| /// Gets a reference to the underlying reader in this decoder. |
| pub fn get_ref(&self) -> &R { |
| &self.rd.rd |
| } |
| |
| /// Gets a mutable reference to the underlying reader in this decoder. |
| pub fn get_mut(&mut self) -> &mut R { |
| &mut self.rd.rd |
| } |
| |
| /// Consumes this deserializer returning the underlying reader. |
| pub fn into_inner(self) -> R { |
| self.rd.rd |
| } |
| } |
| |
| impl<R: AsRef<[u8]>> Deserializer<ReadReader<Cursor<R>>> { |
| /// Returns the current position of this deserializer, i.e. how many bytes were read. |
| pub fn position(&self) -> u64 { |
| self.rd.rd.position() |
| } |
| } |
| |
| impl<'de, R> Deserializer<ReadRefReader<'de, R>> |
| where |
| R: AsRef<[u8]> + ?Sized |
| { |
| /// Constructs a new `Deserializer` from the given byte slice. |
| pub fn from_read_ref(rd: &'de R) -> Self { |
| Deserializer { |
| rd: ReadRefReader::new(rd), |
| marker: None, |
| depth: 1024, |
| } |
| } |
| |
| /// Gets a reference to the underlying reader in this decoder. |
| pub fn get_ref(&self) -> &R { |
| self.rd.rd |
| } |
| } |
| |
| impl<'de, R: ReadSlice<'de>> Deserializer<R> { |
| /// Changes the maximum nesting depth that is allowed |
| pub fn set_max_depth(&mut self, depth: usize) { |
| self.depth = depth; |
| } |
| |
| fn read_str_data<V>(&mut self, len: u32, visitor: V) -> Result<V::Value, Error> |
| where V: Visitor<'de> |
| { |
| match self.read_bin_data(len as u32)? { |
| Reference::Borrowed(buf) => { |
| match str::from_utf8(buf) { |
| Ok(s) => visitor.visit_borrowed_str(s), |
| Err(err) => { |
| // Allow to unpack invalid UTF-8 bytes into a byte array. |
| match visitor.visit_borrowed_bytes::<Error>(buf) { |
| Ok(buf) => Ok(buf), |
| Err(..) => Err(Error::Utf8Error(err)), |
| } |
| } |
| } |
| } |
| Reference::Copied(buf) => { |
| match str::from_utf8(buf) { |
| Ok(s) => visitor.visit_str(s), |
| Err(err) => { |
| // Allow to unpack invalid UTF-8 bytes into a byte array. |
| match visitor.visit_bytes::<Error>(buf) { |
| Ok(buf) => Ok(buf), |
| Err(..) => Err(Error::Utf8Error(err)), |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| fn read_bin_data<'a>(&'a mut self, len: u32) -> Result<Reference<'de,'a, [u8]>, Error> { |
| self.rd.read_slice(len as usize).map_err(Error::InvalidDataRead) |
| } |
| |
| fn read_ext<V>(&mut self, len: u32, visitor: V) -> Result<V::Value, Error> |
| where V: Visitor<'de> |
| { |
| let ext_de = ExtDeserializer::new(self, len); |
| visitor.visit_newtype_struct(ext_de) |
| } |
| |
| fn read_array<V>(&mut self, len: u32, visitor: V) -> Result<V::Value, Error> |
| where V: Visitor<'de> |
| { |
| visitor.visit_seq(SeqAccess::new(self, len as usize)) |
| } |
| |
| fn read_map<V>(&mut self, len: u32, visitor: V) -> Result<V::Value, Error> |
| where V: Visitor<'de> |
| { |
| visitor.visit_map(MapAccess::new(self, len as usize)) |
| } |
| |
| fn read_bytes<V>(&mut self, len: u32, visitor: V) -> Result<V::Value, Error> |
| where V: Visitor<'de> |
| { |
| match self.read_bin_data(len)? { |
| Reference::Borrowed(buf) => visitor.visit_borrowed_bytes(buf), |
| Reference::Copied(buf) => visitor.visit_bytes(buf), |
| } |
| } |
| } |
| |
| fn read_u8<R: Read>(rd: &mut R) -> Result<u8, Error> { |
| rd.read_u8().map_err(Error::InvalidDataRead) |
| } |
| |
| fn read_u16<R: Read>(rd: &mut R) -> Result<u16, Error> { |
| rd.read_u16::<byteorder::BigEndian>().map_err(Error::InvalidDataRead) |
| } |
| |
| fn read_u32<R: Read>(rd: &mut R) -> Result<u32, Error> { |
| rd.read_u32::<byteorder::BigEndian>().map_err(Error::InvalidDataRead) |
| } |
| |
| #[derive(Debug)] |
| enum ExtDeserializerState { |
| New, |
| ReadTag, |
| ReadBinary |
| } |
| |
| #[derive(Debug)] |
| struct ExtDeserializer<'a, R> { |
| rd: &'a mut R, |
| len: u32, |
| state: ExtDeserializerState |
| } |
| |
| impl<'de, 'a, R: ReadSlice<'de> + 'a> ExtDeserializer<'a, R> { |
| fn new(d: &'a mut Deserializer<R>, len: u32) -> Self { |
| ExtDeserializer { |
| rd: &mut d.rd, |
| len, |
| state: ExtDeserializerState::New, |
| } |
| } |
| } |
| |
| impl<'de, 'a, R: ReadSlice<'de> + 'a> de::Deserializer<'de> for ExtDeserializer<'a, R> { |
| type Error = Error; |
| |
| #[inline] |
| fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> |
| where V: Visitor<'de> |
| { |
| visitor.visit_seq(self) |
| } |
| |
| forward_to_deserialize_any! { |
| bool u8 u16 u32 u64 i8 i16 i32 i64 f32 f64 char str string unit option |
| seq bytes byte_buf map unit_struct newtype_struct |
| struct identifier tuple enum ignored_any tuple_struct |
| } |
| } |
| |
| impl<'de, 'a, R: ReadSlice<'de> + 'a> de::SeqAccess<'de> for ExtDeserializer<'a, R> { |
| type Error = Error; |
| |
| fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Error> |
| where |
| T: DeserializeSeed<'de>, |
| { |
| match self.state { |
| ExtDeserializerState::New | ExtDeserializerState::ReadTag => Ok(Some(seed.deserialize(self)?)), |
| ExtDeserializerState::ReadBinary => Ok(None) |
| } |
| } |
| } |
| |
| |
| /// Deserializer for Ext SeqAccess |
| impl<'de, 'a, R: ReadSlice<'de> + 'a> de::Deserializer<'de> for &mut ExtDeserializer<'a, R> { |
| type Error = Error; |
| |
| #[inline] |
| fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> |
| where V: Visitor<'de> |
| { |
| match self.state { |
| ExtDeserializerState::New => { |
| let tag = rmp::decode::read_data_i8(self.rd)?; |
| self.state = ExtDeserializerState::ReadTag; |
| visitor.visit_i8(tag) |
| } |
| ExtDeserializerState::ReadTag => { |
| let data = self.rd.read_slice(self.len as usize).map_err(Error::InvalidDataRead)?; |
| self.state = ExtDeserializerState::ReadBinary; |
| match data { |
| Reference::Borrowed(bytes) => { |
| visitor.visit_borrowed_bytes(bytes) |
| } |
| Reference::Copied(bytes) => { |
| visitor.visit_bytes(bytes) |
| } |
| } |
| } |
| ExtDeserializerState::ReadBinary => unreachable!() |
| } |
| } |
| |
| forward_to_deserialize_any! { |
| bool u8 u16 u32 u64 i8 i16 i32 i64 f32 f64 char str string unit option |
| seq bytes byte_buf map unit_struct newtype_struct |
| tuple_struct struct identifier tuple enum ignored_any |
| } |
| } |
| |
| impl<'de, 'a, R: ReadSlice<'de>> serde::Deserializer<'de> for &'a mut Deserializer<R> { |
| type Error = Error; |
| |
| fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error> |
| where V: Visitor<'de> |
| { |
| let marker = match self.marker.take() { |
| Some(marker) => marker, |
| None => rmp::decode::read_marker(&mut self.rd)?, |
| }; |
| |
| match marker { |
| Marker::Null => visitor.visit_unit(), |
| Marker::True => visitor.visit_bool(true), |
| Marker::False => visitor.visit_bool(false), |
| Marker::FixPos(val) => visitor.visit_u8(val), |
| Marker::FixNeg(val) => visitor.visit_i8(val), |
| Marker::U8 => visitor.visit_u8(rmp::decode::read_data_u8(&mut self.rd)?), |
| Marker::U16 => visitor.visit_u16(rmp::decode::read_data_u16(&mut self.rd)?), |
| Marker::U32 => visitor.visit_u32(rmp::decode::read_data_u32(&mut self.rd)?), |
| Marker::U64 => visitor.visit_u64(rmp::decode::read_data_u64(&mut self.rd)?), |
| Marker::I8 => visitor.visit_i8(rmp::decode::read_data_i8(&mut self.rd)?), |
| Marker::I16 => visitor.visit_i16(rmp::decode::read_data_i16(&mut self.rd)?), |
| Marker::I32 => visitor.visit_i32(rmp::decode::read_data_i32(&mut self.rd)?), |
| Marker::I64 => visitor.visit_i64(rmp::decode::read_data_i64(&mut self.rd)?), |
| Marker::F32 => visitor.visit_f32(rmp::decode::read_data_f32(&mut self.rd)?), |
| Marker::F64 => visitor.visit_f64(rmp::decode::read_data_f64(&mut self.rd)?), |
| Marker::FixStr(len) => { |
| self.read_str_data(len as u32, visitor) |
| } |
| Marker::Str8 => { |
| let len = read_u8(&mut self.rd)?; |
| self.read_str_data(len as u32, visitor) |
| } |
| Marker::Str16 => { |
| let len = read_u16(&mut self.rd)?; |
| self.read_str_data(len as u32, visitor) |
| } |
| Marker::Str32 => { |
| let len = read_u32(&mut self.rd)?; |
| self.read_str_data(len as u32, visitor) |
| } |
| Marker::FixArray(len) => { |
| self.read_array(len as u32, visitor) |
| } |
| Marker::Array16 => { |
| let len = read_u16(&mut self.rd)?; |
| self.read_array(len as u32, visitor) |
| } |
| Marker::Array32 => { |
| let len = read_u32(&mut self.rd)?; |
| self.read_array(len, visitor) |
| } |
| Marker::FixMap(len) => { |
| self.read_map(len as u32, visitor) |
| } |
| Marker::Map16 => { |
| let len = read_u16(&mut self.rd)?; |
| self.read_map(len as u32, visitor) |
| } |
| Marker::Map32 => { |
| let len = read_u32(&mut self.rd)?; |
| self.read_map(len, visitor) |
| } |
| Marker::Bin8 => { |
| let len = read_u8(&mut self.rd)?; |
| self.read_bytes(len as u32, visitor) |
| } |
| Marker::Bin16 => { |
| let len = read_u16(&mut self.rd)?; |
| self.read_bytes(len as u32, visitor) |
| } |
| Marker::Bin32 => { |
| let len = read_u32(&mut self.rd)?; |
| self.read_bytes(len, visitor) |
| } |
| Marker::FixExt1 => { |
| let len = 1 as usize; |
| self.read_ext(len as u32, visitor) |
| } |
| Marker::FixExt2 => { |
| let len = 2 as usize; |
| self.read_ext(len as u32, visitor) |
| } |
| Marker::FixExt4 => { |
| let len = 4 as usize; |
| self.read_ext(len as u32, visitor) |
| } |
| Marker::FixExt8 => { |
| let len = 8 as usize; |
| self.read_ext(len as u32, visitor) |
| } |
| Marker::FixExt16 => { |
| let len = 16 as usize; |
| self.read_ext(len as u32, visitor) |
| } |
| Marker::Ext8 => { |
| let len = read_u8(&mut self.rd)?; |
| self.read_ext(len as u32, visitor) |
| } |
| Marker::Ext16 => { |
| let len = read_u16(&mut self.rd)?; |
| self.read_ext(len as u32, visitor) |
| } |
| Marker::Ext32 => { |
| let len = read_u32(&mut self.rd)?; |
| self.read_ext(len as u32, visitor) |
| } |
| Marker::Reserved => Err(Error::TypeMismatch(Marker::Reserved)), |
| } |
| } |
| |
| fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Self::Error> |
| where V: Visitor<'de> |
| { |
| let marker = rmp::decode::read_marker(&mut self.rd)?; |
| |
| if marker == Marker::Null { |
| visitor.visit_none() |
| } else { |
| self.marker = Some(marker); |
| visitor.visit_some(self) |
| } |
| } |
| |
| fn deserialize_enum<V>(self, _name: &str, _variants: &[&str], visitor: V) -> Result<V::Value, Error> |
| where V: Visitor<'de> |
| { |
| let marker = match self.marker.take() { |
| Some(marker) => marker, |
| None => rmp::decode::read_marker(&mut self.rd)?, |
| }; |
| |
| match rmp::decode::marker_to_len(&mut self.rd, marker)? { |
| 1 => visitor.visit_enum(VariantAccess::new(self)), |
| n => Err(Error::LengthMismatch(n as u32)), |
| } |
| } |
| |
| fn deserialize_newtype_struct<V>(self, name: &'static str, visitor: V) -> Result<V::Value, Error> |
| where V: Visitor<'de> |
| { |
| if name == MSGPACK_EXT_STRUCT_NAME { |
| let marker = match self.marker.take() { |
| Some(marker) => marker, |
| None => rmp::decode::read_marker(&mut self.rd)?, |
| }; |
| let len = match marker { |
| Marker::FixExt1 => { |
| 1 as u32 |
| } |
| Marker::FixExt2 => { |
| 2 as u32 |
| } |
| Marker::FixExt4 => { |
| 4 as u32 |
| } |
| Marker::FixExt8 => { |
| 8 as u32 |
| } |
| Marker::FixExt16 => { |
| 16 as u32 |
| } |
| Marker::Ext8 => { |
| read_u8(&mut self.rd)? as u32 |
| } |
| Marker::Ext16 => { |
| read_u16(&mut self.rd)? as u32 |
| } |
| Marker::Ext32 => { |
| read_u32(&mut self.rd)? as u32 |
| } |
| _ => { |
| return Err(Error::TypeMismatch(marker)) |
| } |
| }; |
| |
| let ext_de = ExtDeserializer::new(self, len); |
| return visitor.visit_newtype_struct(ext_de); |
| } |
| |
| visitor.visit_newtype_struct(self) |
| } |
| |
| fn deserialize_unit_struct<V>(self, _name: &'static str, visitor: V) -> Result<V::Value, Self::Error> |
| where V: Visitor<'de> |
| { |
| // We need to special case this so that [] is treated as a unit struct when asked for, |
| // but as a sequence otherwise. This is because we serialize unit structs as [] rather |
| // than as 'nil'. |
| let marker = match self.marker.take() { |
| Some(marker) => marker, |
| None => rmp::decode::read_marker(&mut self.rd)?, |
| }; |
| match marker { |
| Marker::Null | Marker::FixArray(0) => visitor.visit_unit(), |
| marker => { |
| self.marker = Some(marker); |
| self.deserialize_any(visitor) |
| } |
| } |
| } |
| |
| fn deserialize_f32<V>(self, visitor: V) -> Result<V::Value, Self::Error> |
| where V: Visitor<'de> |
| { |
| // This special case allows us to decode some integer types as floats when safe, and |
| // asked for. |
| // |
| // This allows interoperability with msgpack-lite, which performs an optimization of |
| // storing rounded floats as integers. |
| let marker = match self.marker.take() { |
| Some(marker) => marker, |
| None => rmp::decode::read_marker(&mut self.rd)?, |
| }; |
| match marker { |
| Marker::U8 => visitor.visit_f32(rmp::decode::read_data_u8(&mut self.rd)?.into()), |
| Marker::U16 => visitor.visit_f32(rmp::decode::read_data_u16(&mut self.rd)?.into()), |
| Marker::I8 => visitor.visit_f32(rmp::decode::read_data_i8(&mut self.rd)?.into()), |
| Marker::I16 => visitor.visit_f32(rmp::decode::read_data_i16(&mut self.rd)?.into()), |
| Marker::F32 => visitor.visit_f32(rmp::decode::read_data_f32(&mut self.rd)?), |
| marker => { |
| self.marker = Some(marker); |
| self.deserialize_any(visitor) |
| } |
| } |
| } |
| |
| fn deserialize_f64<V>(self, visitor: V) -> Result<V::Value, Self::Error> |
| where V: Visitor<'de> |
| { |
| // This special case allows us to decode some integer types as floats when safe, and |
| // asked for. This is here to be consistent with 'f32'. |
| let marker = match self.marker.take() { |
| Some(marker) => marker, |
| None => rmp::decode::read_marker(&mut self.rd)?, |
| }; |
| match marker { |
| Marker::U8 => visitor.visit_f64(rmp::decode::read_data_u8(&mut self.rd)?.into()), |
| Marker::U16 => visitor.visit_f64(rmp::decode::read_data_u16(&mut self.rd)?.into()), |
| Marker::U32 => visitor.visit_f64(rmp::decode::read_data_u32(&mut self.rd)?.into()), |
| Marker::I8 => visitor.visit_f64(rmp::decode::read_data_i8(&mut self.rd)?.into()), |
| Marker::I16 => visitor.visit_f64(rmp::decode::read_data_i16(&mut self.rd)?.into()), |
| Marker::I32 => visitor.visit_f64(rmp::decode::read_data_i32(&mut self.rd)?.into()), |
| Marker::F32 => visitor.visit_f64(rmp::decode::read_data_f32(&mut self.rd)?.into()), |
| Marker::F64 => visitor.visit_f64(rmp::decode::read_data_f64(&mut self.rd)?), |
| marker => { |
| self.marker = Some(marker); |
| self.deserialize_any(visitor) |
| } |
| } |
| } |
| |
| forward_to_deserialize_any! { |
| bool u8 u16 u32 u64 i8 i16 i32 i64 char |
| str string bytes byte_buf unit seq map |
| struct identifier tuple tuple_struct |
| ignored_any |
| } |
| } |
| |
| struct SeqAccess<'a, R> { |
| de: &'a mut Deserializer<R>, |
| left: usize, |
| } |
| |
| impl<'a, R: 'a> SeqAccess<'a, R> { |
| fn new(de: &'a mut Deserializer<R>, len: usize) -> Self { |
| SeqAccess { |
| de, |
| left: len, |
| } |
| } |
| } |
| |
| impl<'de, 'a, R: ReadSlice<'de> + 'a> de::SeqAccess<'de> for SeqAccess<'a, R> { |
| type Error = Error; |
| |
| fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error> |
| where T: DeserializeSeed<'de> |
| { |
| if self.left > 0 { |
| self.left -= 1; |
| Ok(Some(seed.deserialize(&mut *self.de)?)) |
| } else { |
| Ok(None) |
| } |
| } |
| |
| fn size_hint(&self) -> Option<usize> { |
| Some(self.left) |
| } |
| } |
| |
| struct MapAccess<'a, R> { |
| de: &'a mut Deserializer<R>, |
| left: usize, |
| } |
| |
| impl<'a, R: 'a> MapAccess<'a, R> { |
| fn new(de: &'a mut Deserializer<R>, len: usize) -> Self { |
| MapAccess { |
| de, |
| left: len, |
| } |
| } |
| } |
| |
| impl<'de, 'a, R: ReadSlice<'de> + 'a> de::MapAccess<'de> for MapAccess<'a, R> { |
| type Error = Error; |
| |
| fn next_key_seed<K>(&mut self, seed: K) -> Result<Option<K::Value>, Self::Error> |
| where K: DeserializeSeed<'de> |
| { |
| if self.left > 0 { |
| self.left -= 1; |
| Ok(Some(seed.deserialize(&mut *self.de)?)) |
| } else { |
| Ok(None) |
| } |
| } |
| |
| fn next_value_seed<V>(&mut self, seed: V) -> Result<V::Value, Self::Error> |
| where V: DeserializeSeed<'de> |
| { |
| Ok(seed.deserialize(&mut *self.de)?) |
| } |
| |
| fn size_hint(&self) -> Option<usize> { |
| Some(self.left) |
| } |
| } |
| |
| struct VariantAccess<'a, R> { |
| de: &'a mut Deserializer<R>, |
| } |
| |
| impl<'a, R: 'a> VariantAccess<'a, R> { |
| pub fn new(de: &'a mut Deserializer<R>) -> Self { |
| VariantAccess { |
| de, |
| } |
| } |
| } |
| |
| impl<'de, 'a, R: ReadSlice<'de>> de::EnumAccess<'de> for VariantAccess<'a, R> { |
| type Error = Error; |
| type Variant = Self; |
| |
| fn variant_seed<V>(self, seed: V) -> Result<(V::Value, Self), Error> |
| where V: de::DeserializeSeed<'de>, |
| { |
| Ok((seed.deserialize(&mut *self.de)?, self)) |
| } |
| } |
| |
| impl<'de, 'a, R: ReadSlice<'de>> de::VariantAccess<'de> for VariantAccess<'a, R> { |
| type Error = Error; |
| |
| fn unit_variant(self) -> Result<(), Error> { |
| decode::read_nil(&mut self.de.rd)?; |
| Ok(()) |
| } |
| |
| fn newtype_variant_seed<T>(self, seed: T) -> Result<T::Value, Self::Error> |
| where T: DeserializeSeed<'de> |
| { |
| seed.deserialize(self.de) |
| } |
| |
| fn tuple_variant<V>(self, len: usize, visitor: V) -> Result<V::Value, Error> |
| where V: Visitor<'de> |
| { |
| de::Deserializer::deserialize_tuple(self.de, len, visitor) |
| } |
| |
| fn struct_variant<V>(self, fields: &'static [&'static str], visitor: V) -> Result<V::Value, Error> |
| where V: Visitor<'de> |
| { |
| de::Deserializer::deserialize_tuple(self.de, fields.len(), visitor) |
| } |
| } |
| |
| /// Unification of both borrowed and non-borrowed reference types. |
| #[derive(Clone, Copy, Debug, PartialEq)] |
| pub enum Reference<'b, 'c, T: ?Sized + 'static> { |
| /// The reference is pointed at data that was borrowed. |
| Borrowed(&'b T), |
| /// The reference is pointed at data that was copied. |
| Copied(&'c T), |
| } |
| |
| /// Extends the `Read` trait by allowing to read slices directly by borrowing bytes. |
| /// |
| /// Used to allow zero-copy reading. |
| pub trait ReadSlice<'de>: Read { |
| /// Reads the exact number of bytes from the underlying byte-array. |
| fn read_slice<'a>(&'a mut self, len: usize) -> Result<Reference<'de, 'a, [u8]>, io::Error>; |
| } |
| |
| /// Owned reader wrapper. |
| #[derive(Debug)] |
| pub struct ReadReader<R: Read> { |
| rd: R, |
| buf: Vec<u8>, |
| } |
| |
| impl<R: Read> ReadReader<R> { |
| fn new(rd: R) -> Self { |
| ReadReader { |
| rd, |
| buf: Vec::with_capacity(128), |
| } |
| } |
| } |
| |
| impl<'de, R: Read> ReadSlice<'de> for ReadReader<R> { |
| #[inline] |
| fn read_slice<'a>(&'a mut self, len: usize) -> Result<Reference<'de, 'a, [u8]>, io::Error> { |
| self.buf.resize(len, 0u8); |
| self.rd.read_exact(&mut self.buf[..])?; |
| |
| Ok(Reference::Copied(&self.buf[..])) |
| } |
| } |
| |
| impl<R: Read> Read for ReadReader<R> { |
| #[inline] |
| fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { |
| self.rd.read(buf) |
| } |
| |
| #[inline] |
| fn read_exact(&mut self, buf: &mut [u8]) -> io::Result<()> { |
| self.rd.read_exact(buf) |
| } |
| } |
| |
| /// Borrowed reader wrapper. |
| #[derive(Debug)] |
| pub struct ReadRefReader<'a, R: ?Sized> { |
| rd: &'a R, |
| buf: &'a [u8], |
| } |
| |
| impl<'a, T: AsRef<[u8]> + ?Sized> ReadRefReader<'a, T> { |
| fn new(rd: &'a T) -> Self { |
| Self { |
| rd, |
| buf: rd.as_ref() |
| } |
| } |
| } |
| |
| impl<'a, T: AsRef<[u8]> + ?Sized> Read for ReadRefReader<'a, T> { |
| #[inline] |
| fn read(&mut self, buf: &mut [u8]) -> Result<usize, io::Error> { |
| self.buf.read(buf) |
| } |
| |
| #[inline] |
| fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), io::Error> { |
| self.buf.read_exact(buf) |
| } |
| } |
| |
| impl<'de, T: AsRef<[u8]> + ?Sized> ReadSlice<'de> for ReadRefReader<'de, T> { |
| #[inline] |
| fn read_slice<'a>(&'a mut self, len: usize) -> Result<Reference<'de, 'a, [u8]>, io::Error> { |
| if len > self.buf.len() { |
| return Err(ErrorKind::UnexpectedEof.into()); |
| } |
| let (a, b) = self.buf.split_at(len); |
| self.buf = b; |
| Ok(Reference::Borrowed(a)) |
| } |
| } |
| |
| #[test] |
| fn test_as_ref_reader() { |
| let buf = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]; |
| let mut rd = ReadRefReader::new(&buf); |
| |
| assert_eq!(rd.read_slice(1).unwrap(), Reference::Borrowed(&[0][..])); |
| assert_eq!(rd.read_slice(6).unwrap(), Reference::Borrowed(&[1, 2, 3, 4, 5, 6][..])); |
| assert!(rd.read_slice(5).is_err()); |
| assert_eq!(rd.read_slice(4).unwrap(), Reference::Borrowed(&[7, 8, 9, 10][..])); |
| } |
| |
| /// Deserialize an instance of type `T` from an I/O stream of MessagePack. |
| /// |
| /// # Errors |
| /// |
| /// This conversion can fail if the structure of the Value does not match the structure expected |
| /// by `T`. It can also fail if the structure is correct but `T`'s implementation of `Deserialize` |
| /// decides that something is wrong with the data, for example required struct fields are missing. |
| pub fn from_read<R, T>(rd: R) -> Result<T, Error> |
| where R: Read, |
| T: DeserializeOwned |
| { |
| Deserialize::deserialize(&mut Deserializer::new(rd)) |
| } |
| |
| /// Deserializes a byte slice into the desired type. |
| /// |
| /// Currently deprecated, use more generic `from_read_ref` instead. |
| #[doc(hidden)] |
| pub fn from_slice<'a, T>(input: &'a [u8]) -> Result<T, Error> |
| where |
| T: Deserialize<'a> |
| { |
| from_read_ref(input) |
| } |
| |
| /// Deserialize an instance of type `T` from a reference I/O reader of MessagePack. |
| /// |
| /// Deserialization will be performed in zero-copy manner whenever it is possible, borrowing the |
| /// data from the reader itself. For example, strings and byte-arrays won't be not copied. |
| /// |
| /// # Errors |
| /// |
| /// This conversion can fail if the structure of the Value does not match the structure expected |
| /// by `T`. It can also fail if the structure is correct but `T`'s implementation of `Deserialize` |
| /// decides that something is wrong with the data, for example required struct fields are missing. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// # #[macro_use] extern crate serde_derive; |
| /// |
| /// // Encoded `["Bobby", 8]`. |
| /// let buf = [0x92, 0xa5, 0x42, 0x6f, 0x62, 0x62, 0x79, 0x8]; |
| /// |
| /// #[derive(Debug, Deserialize, PartialEq)] |
| /// struct Dog<'a> { |
| /// name: &'a str, |
| /// age: u8, |
| /// } |
| /// |
| /// assert_eq!(Dog { name: "Bobby", age: 8 }, rmp_serde::from_read_ref(&buf).unwrap()); |
| /// ``` |
| #[inline] |
| pub fn from_read_ref<'a, R, T>(rd: &'a R) -> Result<T, Error> |
| where |
| R: AsRef<[u8]> + ?Sized, |
| T: Deserialize<'a>, |
| { |
| let mut de = Deserializer::from_read_ref(rd); |
| Deserialize::deserialize(&mut de) |
| } |
