1 use crate::leb128::{self, read_signed_leb128, write_signed_leb128};
5 // -----------------------------------------------------------------------------
7 // -----------------------------------------------------------------------------
9 pub type EncodeResult = Result<(), !>;
16 pub fn new(data: Vec<u8>) -> Encoder {
20 pub fn into_inner(self) -> Vec<u8> {
25 pub fn emit_raw_bytes(&mut self, s: &[u8]) {
26 self.data.extend_from_slice(s);
30 macro_rules! write_uleb128 {
31 ($enc:expr, $value:expr, $fun:ident) => {{
32 leb128::$fun(&mut $enc.data, $value);
37 macro_rules! write_sleb128 {
38 ($enc:expr, $value:expr) => {{
39 write_signed_leb128(&mut $enc.data, $value as i128);
44 impl serialize::Encoder for Encoder {
48 fn emit_unit(&mut self) -> EncodeResult {
53 fn emit_usize(&mut self, v: usize) -> EncodeResult {
54 write_uleb128!(self, v, write_usize_leb128)
58 fn emit_u128(&mut self, v: u128) -> EncodeResult {
59 write_uleb128!(self, v, write_u128_leb128)
63 fn emit_u64(&mut self, v: u64) -> EncodeResult {
64 write_uleb128!(self, v, write_u64_leb128)
68 fn emit_u32(&mut self, v: u32) -> EncodeResult {
69 write_uleb128!(self, v, write_u32_leb128)
73 fn emit_u16(&mut self, v: u16) -> EncodeResult {
74 write_uleb128!(self, v, write_u16_leb128)
78 fn emit_u8(&mut self, v: u8) -> EncodeResult {
84 fn emit_isize(&mut self, v: isize) -> EncodeResult {
85 write_sleb128!(self, v)
89 fn emit_i128(&mut self, v: i128) -> EncodeResult {
90 write_sleb128!(self, v)
94 fn emit_i64(&mut self, v: i64) -> EncodeResult {
95 write_sleb128!(self, v)
99 fn emit_i32(&mut self, v: i32) -> EncodeResult {
100 write_sleb128!(self, v)
104 fn emit_i16(&mut self, v: i16) -> EncodeResult {
105 write_sleb128!(self, v)
109 fn emit_i8(&mut self, v: i8) -> EncodeResult {
110 let as_u8: u8 = unsafe { ::std::mem::transmute(v) };
115 fn emit_bool(&mut self, v: bool) -> EncodeResult {
116 self.emit_u8(if v { 1 } else { 0 })
120 fn emit_f64(&mut self, v: f64) -> EncodeResult {
121 let as_u64: u64 = unsafe { ::std::mem::transmute(v) };
122 self.emit_u64(as_u64)
126 fn emit_f32(&mut self, v: f32) -> EncodeResult {
127 let as_u32: u32 = unsafe { ::std::mem::transmute(v) };
128 self.emit_u32(as_u32)
132 fn emit_char(&mut self, v: char) -> EncodeResult {
133 self.emit_u32(v as u32)
137 fn emit_str(&mut self, v: &str) -> EncodeResult {
138 self.emit_usize(v.len())?;
139 self.emit_raw_bytes(v.as_bytes());
146 pub fn position(&self) -> usize {
151 // -----------------------------------------------------------------------------
153 // -----------------------------------------------------------------------------
155 pub struct Decoder<'a> {
160 impl<'a> Decoder<'a> {
162 pub fn new(data: &'a [u8], position: usize) -> Decoder<'a> {
163 Decoder { data, position }
167 pub fn position(&self) -> usize {
172 pub fn set_position(&mut self, pos: usize) {
177 pub fn advance(&mut self, bytes: usize) {
178 self.position += bytes;
182 pub fn read_raw_bytes(&mut self, s: &mut [u8]) -> Result<(), String> {
183 let start = self.position;
184 let end = start + s.len();
186 s.copy_from_slice(&self.data[start..end]);
194 macro_rules! read_uleb128 {
195 ($dec:expr, $t:ty, $fun:ident) => {{
196 let (value, bytes_read) = leb128::$fun(&$dec.data[$dec.position..]);
197 $dec.position += bytes_read;
202 macro_rules! read_sleb128 {
203 ($dec:expr, $t:ty) => {{
204 let (value, bytes_read) = read_signed_leb128($dec.data, $dec.position);
205 $dec.position += bytes_read;
210 impl<'a> serialize::Decoder for Decoder<'a> {
214 fn read_nil(&mut self) -> Result<(), Self::Error> {
219 fn read_u128(&mut self) -> Result<u128, Self::Error> {
220 read_uleb128!(self, u128, read_u128_leb128)
224 fn read_u64(&mut self) -> Result<u64, Self::Error> {
225 read_uleb128!(self, u64, read_u64_leb128)
229 fn read_u32(&mut self) -> Result<u32, Self::Error> {
230 read_uleb128!(self, u32, read_u32_leb128)
234 fn read_u16(&mut self) -> Result<u16, Self::Error> {
235 read_uleb128!(self, u16, read_u16_leb128)
239 fn read_u8(&mut self) -> Result<u8, Self::Error> {
240 let value = self.data[self.position];
246 fn read_usize(&mut self) -> Result<usize, Self::Error> {
247 read_uleb128!(self, usize, read_usize_leb128)
251 fn read_i128(&mut self) -> Result<i128, Self::Error> {
252 read_sleb128!(self, i128)
256 fn read_i64(&mut self) -> Result<i64, Self::Error> {
257 read_sleb128!(self, i64)
261 fn read_i32(&mut self) -> Result<i32, Self::Error> {
262 read_sleb128!(self, i32)
266 fn read_i16(&mut self) -> Result<i16, Self::Error> {
267 read_sleb128!(self, i16)
271 fn read_i8(&mut self) -> Result<i8, Self::Error> {
272 let as_u8 = self.data[self.position];
274 unsafe { Ok(::std::mem::transmute(as_u8)) }
278 fn read_isize(&mut self) -> Result<isize, Self::Error> {
279 read_sleb128!(self, isize)
283 fn read_bool(&mut self) -> Result<bool, Self::Error> {
284 let value = self.read_u8()?;
289 fn read_f64(&mut self) -> Result<f64, Self::Error> {
290 let bits = self.read_u64()?;
291 Ok(f64::from_bits(bits))
295 fn read_f32(&mut self) -> Result<f32, Self::Error> {
296 let bits = self.read_u32()?;
297 Ok(f32::from_bits(bits))
301 fn read_char(&mut self) -> Result<char, Self::Error> {
302 let bits = self.read_u32()?;
303 Ok(::std::char::from_u32(bits).unwrap())
307 fn read_str(&mut self) -> Result<Cow<'_, str>, Self::Error> {
308 let len = self.read_usize()?;
309 let s = ::std::str::from_utf8(&self.data[self.position..self.position + len]).unwrap();
310 self.position += len;
315 fn error(&mut self, err: &str) -> Self::Error {