use encode_unicode::CharExt;
use serde::Serialize;
use crate::Error;
pub struct Serializer<'a> {
buf: &'a mut [u8],
ofs: usize,
}
impl<'a> Serializer<'a> {
pub fn new(buf: &'a mut [u8]) -> Self {
Serializer { buf, ofs: 0 }
}
pub fn into_offset(self) -> usize {
self.ofs
}
#[inline(always)]
fn assert_space(&self, space: usize) -> Result<(), Error> {
if self.ofs + space > self.buf.len() {
Err(Error::OutOfSpace)
} else {
Ok(())
}
}
#[inline(always)]
fn write_u8(&mut self, v: u8) -> Result<(), Error> {
self.assert_space(1)?;
unsafe {
*self.buf.get_unchecked_mut(self.ofs) = v;
}
self.ofs += 1;
Ok(())
}
#[inline(always)]
fn write_str(&mut self, s: &str) -> Result<(), Error> {
let bytes = s.as_bytes();
let len = bytes.len();
self.assert_space(len + 2)?;
unsafe {
*self.buf.get_unchecked_mut(self.ofs) = (len & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 1) = (len >> 8 & 0xFF) as u8;
}
let start = self.ofs + 2;
let end = start + len;
self.buf[start..end].clone_from_slice(bytes);
self.ofs += len + 2;
Ok(())
}
#[inline(always)]
fn write_u16(&mut self, v: u16) -> Result<(), Error> {
self.assert_space(2)?;
unsafe {
*self.buf.get_unchecked_mut(self.ofs) = (v & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 1) = (v >> 8 & 0xFF) as u8;
}
self.ofs += 2;
Ok(())
}
#[inline(always)]
fn write_u32(&mut self, v: u32) -> Result<(), Error> {
self.assert_space(4)?;
unsafe {
*self.buf.get_unchecked_mut(self.ofs) = (v & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 1) = (v >> 8 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 2) = (v >> 16 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 3) = (v >> 24 & 0xFF) as u8;
}
self.ofs += 4;
Ok(())
}
#[inline(always)]
fn write_u64(&mut self, v: u64) -> Result<(), Error> {
self.assert_space(8)?;
unsafe {
*self.buf.get_unchecked_mut(self.ofs) = (v & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 1) = (v >> 8 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 2) = (v >> 16 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 3) = (v >> 24 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 4) = (v >> 32 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 5) = (v >> 40 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 6) = (v >> 48 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 7) = (v >> 56 & 0xFF) as u8;
}
self.ofs += 8;
Ok(())
}
#[inline(always)]
fn write_u128(&mut self, v: u128) -> Result<(), Error> {
self.assert_space(16)?;
unsafe {
*self.buf.get_unchecked_mut(self.ofs) = (v & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 1) = (v >> 8 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 2) = (v >> 16 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 3) = (v >> 24 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 4) = (v >> 32 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 5) = (v >> 40 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 6) = (v >> 48 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 7) = (v >> 56 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 8) = (v >> 64 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 9) = (v >> 72 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 10) = (v >> 80 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 11) = (v >> 88 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 12) = (v >> 96 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 13) =
(v >> 104 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 14) =
(v >> 112 & 0xFF) as u8;
*self.buf.get_unchecked_mut(self.ofs + 15) =
(v >> 120 & 0xFF) as u8;
}
self.ofs += 16;
Ok(())
}
}
impl<'b, 'a> serde::ser::Serializer for &'a mut Serializer<'b> {
type Ok = ();
type Error = Error;
type SerializeSeq = Self;
type SerializeTuple = Self;
type SerializeTupleStruct = Self;
type SerializeTupleVariant = Self;
type SerializeMap = serde::ser::Impossible<(), Error>;
type SerializeStruct = Self;
type SerializeStructVariant = Self;
fn serialize_bool(self, v: bool) -> Result<Self::Ok, Self::Error> {
self.write_u8(if v { 1 } else { 0 })
}
fn serialize_i8(self, v: i8) -> Result<Self::Ok, Self::Error> {
self.write_u8(v as u8)
}
fn serialize_i16(self, v: i16) -> Result<Self::Ok, Self::Error> {
self.write_u16(v as u16)
}
fn serialize_i32(self, v: i32) -> Result<Self::Ok, Self::Error> {
self.write_u32(v as u32)
}
fn serialize_i64(self, v: i64) -> Result<Self::Ok, Self::Error> {
self.write_u64(v as u64)
}
fn serialize_i128(self, v: i128) -> Result<Self::Ok, Self::Error> {
self.write_u128(v as u128)
}
fn serialize_u8(self, v: u8) -> Result<Self::Ok, Self::Error> {
self.write_u8(v)
}
fn serialize_u16(self, v: u16) -> Result<Self::Ok, Self::Error> {
self.write_u16(v)
}
fn serialize_u32(self, v: u32) -> Result<Self::Ok, Self::Error> {
self.write_u32(v)
}
fn serialize_u64(self, v: u64) -> Result<Self::Ok, Self::Error> {
self.write_u64(v)
}
fn serialize_u128(self, v: u128) -> Result<Self::Ok, Self::Error> {
self.write_u128(v)
}
fn serialize_f32(self, _v: f32) -> Result<Self::Ok, Self::Error> {
Err(Error::NotSupported)
}
fn serialize_f64(self, _v: f64) -> Result<Self::Ok, Self::Error> {
Err(Error::NotSupported)
}
fn serialize_char(self, v: char) -> Result<Self::Ok, Self::Error> {
let (arr, sz) = v.to_utf8_array();
self.assert_space(sz)?;
for (i, c) in arr[..sz].iter().enumerate() {
unsafe {
*self.buf.get_unchecked_mut(self.ofs + i) = *c;
}
}
self.ofs += sz;
Ok(())
}
fn serialize_str(self, v: &str) -> Result<Self::Ok, Self::Error> {
self.write_str(v)
}
fn serialize_bytes(self, _v: &[u8]) -> Result<Self::Ok, Self::Error> {
unimplemented!()
}
fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
self.write_u8(0)
}
fn serialize_some<T: ?Sized>(
self,
value: &T,
) -> Result<Self::Ok, Self::Error>
where
T: Serialize,
{
self.write_u8(1)?;
value.serialize(self)
}
fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
Ok(())
}
fn serialize_unit_struct(
self,
_name: &'static str,
) -> Result<Self::Ok, Self::Error> {
Ok(())
}
fn serialize_unit_variant(
self,
_name: &'static str,
variant_index: u32,
_variant: &'static str,
) -> Result<Self::Ok, Self::Error> {
if variant_index > 255 {
return Err(Error::TooManyVariants);
}
self.write_u8(variant_index as u8)
}
fn serialize_newtype_struct<T: ?Sized>(
self,
_name: &'static str,
value: &T,
) -> Result<Self::Ok, Self::Error>
where
T: Serialize,
{
value.serialize(self)
}
fn serialize_newtype_variant<T: ?Sized>(
self,
_name: &'static str,
variant_index: u32,
_variant: &'static str,
value: &T,
) -> Result<Self::Ok, Self::Error>
where
T: Serialize,
{
if variant_index > 255 {
return Err(Error::TooManyVariants);
}
self.write_u8(variant_index as u8)?;
value.serialize(self)
}
fn serialize_seq(
self,
len: Option<usize>,
) -> Result<Self::SerializeSeq, Self::Error> {
let len = len.unwrap_or(0);
if len > core::u16::MAX as usize {
Err(Error::LengthExceeded)
} else {
self.write_u16(len as u16)?;
Ok(self)
}
}
fn serialize_tuple(
self,
_len: usize,
) -> Result<Self::SerializeTuple, Self::Error> {
Ok(self)
}
fn serialize_tuple_struct(
self,
_name: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleStruct, Self::Error> {
Ok(self)
}
fn serialize_tuple_variant(
self,
_name: &'static str,
variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeTupleVariant, Self::Error> {
if variant_index > 255 {
return Err(Error::TooManyVariants);
}
self.write_u8(variant_index as u8)?;
Ok(self)
}
fn serialize_map(
self,
_len: Option<usize>,
) -> Result<Self::SerializeMap, Self::Error> {
Err(Error::NotSupported)
}
fn serialize_struct(
self,
_name: &'static str,
_len: usize,
) -> Result<Self::SerializeStruct, Self::Error> {
Ok(self)
}
fn serialize_struct_variant(
self,
_name: &'static str,
variant_index: u32,
_variant: &'static str,
_len: usize,
) -> Result<Self::SerializeStructVariant, Self::Error> {
if variant_index > 255 {
return Err(Error::TooManyVariants);
}
self.write_u8(variant_index as u8)?;
Ok(self)
}
fn collect_str<T: ?Sized>(self, _value: &T) -> Result<Self::Ok, Self::Error>
where
T: core::fmt::Display,
{
Err(Error::NotSupported)
}
#[inline]
fn is_human_readable(&self) -> bool {
false
}
}
impl<'b, 'a: 'b> serde::ser::SerializeStructVariant for &'b mut Serializer<'a> {
type Ok = ();
type Error = Error;
fn serialize_field<T: ?Sized>(
&mut self,
_key: &'static str,
value: &T,
) -> Result<(), Self::Error>
where
T: Serialize,
{
value.serialize(&mut **self)
}
fn end(self) -> Result<Self::Ok, Self::Error> {
Ok(())
}
}
impl<'b, 'a: 'b> serde::ser::SerializeStruct for &'b mut Serializer<'a> {
type Ok = ();
type Error = Error;
fn serialize_field<T: ?Sized>(
&mut self,
_key: &'static str,
value: &T,
) -> Result<(), Self::Error>
where
T: Serialize,
{
value.serialize(&mut **self)
}
fn end(self) -> Result<Self::Ok, Self::Error> {
Ok(())
}
}
impl<'b, 'a: 'b> serde::ser::SerializeTupleVariant for &'b mut Serializer<'a> {
type Ok = ();
type Error = Error;
fn serialize_field<T: ?Sized>(
&mut self,
value: &T,
) -> Result<(), Self::Error>
where
T: Serialize,
{
value.serialize(&mut **self)
}
fn end(self) -> Result<Self::Ok, Self::Error> {
Ok(())
}
}
impl<'b, 'a: 'b> serde::ser::SerializeTupleStruct for &'b mut Serializer<'a> {
type Ok = ();
type Error = Error;
fn serialize_field<T: ?Sized>(
&mut self,
value: &T,
) -> Result<(), Self::Error>
where
T: Serialize,
{
value.serialize(&mut **self)
}
fn end(self) -> Result<Self::Ok, Self::Error> {
Ok(())
}
}
impl<'b, 'a: 'b> serde::ser::SerializeTuple for &'b mut Serializer<'a> {
type Ok = ();
type Error = Error;
fn serialize_element<T: ?Sized>(
&mut self,
value: &T,
) -> Result<(), Self::Error>
where
T: Serialize,
{
value.serialize(&mut **self)
}
fn end(self) -> Result<Self::Ok, Self::Error> {
Ok(())
}
}
impl<'b, 'a: 'b> serde::ser::SerializeSeq for &'b mut Serializer<'a> {
type Ok = ();
type Error = Error;
fn serialize_element<T: ?Sized>(
&mut self,
value: &T,
) -> Result<(), Self::Error>
where
T: Serialize,
{
value.serialize(&mut **self)
}
fn end(self) -> Result<Self::Ok, Self::Error> {
Ok(())
}
}