preserves/implementations/rust/src/value/reader.rs

846 lines
31 KiB
Rust

use num::bigint::BigInt;
use num::traits::cast::{FromPrimitive, ToPrimitive};
use std::borrow::Cow;
use std::convert::TryFrom;
use std::convert::TryInto;
use std::io::{Read, Error};
use std::marker::PhantomData;
use super::constants::{Op, InvalidOp, AtomMinor, CompoundMinor};
use super::value::{Value, NestedValue, IOValue, FALSE, TRUE, Map, Set};
use crate::error::{self, ExpectedKind, Received, is_eof_io_error, io_eof, io_syntax_error};
pub type IOResult<T> = std::result::Result<T, Error>;
pub type ReaderResult<T> = std::result::Result<T, error::Error>;
#[derive(Debug)]
pub struct CompoundBody {
minor: CompoundMinor,
limit: CompoundLimit,
}
#[derive(Debug)]
pub enum CompoundLimit {
Counted(usize),
Streaming,
}
impl CompoundBody {
pub fn counted(minor: CompoundMinor, size: usize) -> Self {
CompoundBody { minor, limit: CompoundLimit::Counted(size) }
}
pub fn streaming(minor: CompoundMinor) -> Self {
CompoundBody { minor, limit: CompoundLimit::Streaming }
}
pub fn more_expected<'de, R: Reader<'de>>(&mut self, read: &mut R) -> ReaderResult<bool> {
match self.limit {
CompoundLimit::Counted(ref mut n) =>
if *n == 0 {
read.close_compound_counted(self.minor)?;
Ok(false)
} else {
*n = *n - 1;
Ok(true)
},
CompoundLimit::Streaming =>
Ok(!read.close_compound_stream(self.minor)?),
}
}
pub fn next_symbol<'de, R: Reader<'de>>(&mut self, read: &mut R) -> ReaderResult<Option<Cow<'de, str>>> {
match self.more_expected(read)? {
false => Ok(None),
true => Ok(Some(read.next_symbol()?)),
}
}
pub fn next_value<'de, R: Reader<'de>>(&mut self, read: &mut R, read_annotations: bool) ->
ReaderResult<Option<IOValue>>
{
match self.more_expected(read)? {
false => Ok(None),
true => Ok(Some(read.demand_next(read_annotations)?.into_owned())),
}
}
pub fn remainder<'de, R: Reader<'de>>(&mut self, read: &mut R, read_annotations: bool) ->
ReaderResult<Vec<IOValue>>
{
let mut result = Vec::new();
while let Some(v) = self.next_value(read, read_annotations)? {
result.push(v);
}
Ok(result)
}
pub fn ensure_more_expected<'de, R: Reader<'de>>(&mut self, read: &mut R) -> ReaderResult<()> {
if self.more_expected(read)? {
Ok(())
} else {
Err(error::Error::MissingItem)
}
}
pub fn ensure_complete<'de, R: Reader<'de>>(&mut self, read: &mut R) -> ReaderResult<()> {
if self.more_expected(read)? {
Err(error::Error::MissingCloseDelimiter)
} else {
Ok(())
}
}
}
pub trait Reader<'de> {
fn next(&mut self, read_annotations: bool) -> IOResult<Option<Cow<'de, IOValue>>>;
fn open_record(&mut self, arity: Option<usize>) -> ReaderResult<CompoundBody>;
fn open_sequence_or_set(&mut self) -> ReaderResult<CompoundBody>;
fn open_sequence(&mut self) -> ReaderResult<CompoundBody>;
fn open_set(&mut self) -> ReaderResult<CompoundBody>;
fn open_dictionary(&mut self) -> ReaderResult<CompoundBody>;
fn close_compound_counted(&mut self, minor: CompoundMinor) -> ReaderResult<()>;
fn close_compound_stream(&mut self, minor: CompoundMinor) -> ReaderResult<bool>;
//---------------------------------------------------------------------------
fn skip_value(&mut self) -> IOResult<()> {
// TODO efficient skipping in specific impls of this trait
let _ = self.demand_next(false)?;
Ok(())
}
fn demand_next(&mut self, read_annotations: bool) -> IOResult<Cow<'de, IOValue>> {
match self.next(read_annotations)? {
None => Err(io_eof()),
Some(v) => Ok(v)
}
}
fn next_boolean(&mut self) -> ReaderResult<bool> { self.demand_next(false)?.value().to_boolean() }
fn next_i8(&mut self) -> ReaderResult<i8> { self.demand_next(false)?.value().to_i8() }
fn next_u8(&mut self) -> ReaderResult<u8> { self.demand_next(false)?.value().to_u8() }
fn next_i16(&mut self) -> ReaderResult<i16> { self.demand_next(false)?.value().to_i16() }
fn next_u16(&mut self) -> ReaderResult<u16> { self.demand_next(false)?.value().to_u16() }
fn next_i32(&mut self) -> ReaderResult<i32> { self.demand_next(false)?.value().to_i32() }
fn next_u32(&mut self) -> ReaderResult<u32> { self.demand_next(false)?.value().to_u32() }
fn next_i64(&mut self) -> ReaderResult<i64> { self.demand_next(false)?.value().to_i64() }
fn next_u64(&mut self) -> ReaderResult<u64> { self.demand_next(false)?.value().to_u64() }
fn next_float(&mut self) -> ReaderResult<f32> { self.demand_next(false)?.value().to_float() }
fn next_double(&mut self) -> ReaderResult<f64> { self.demand_next(false)?.value().to_double() }
fn next_char(&mut self) -> ReaderResult<char> { self.demand_next(false)?.value().to_char() }
fn next_str(&mut self) -> ReaderResult<Cow<'de, str>> {
Ok(Cow::Owned(self.demand_next(false)?.value().to_string()?.to_owned()))
}
fn next_bytestring(&mut self) -> ReaderResult<Cow<'de, [u8]>> {
Ok(Cow::Owned(self.demand_next(false)?.value().to_bytestring()?.to_owned()))
}
fn next_symbol(&mut self) -> ReaderResult<Cow<'de, str>> {
Ok(Cow::Owned(self.demand_next(false)?.value().to_symbol()?.to_owned()))
}
fn open_option(&mut self) ->
ReaderResult<(bool, CompoundBody)>
where
Self: Sized
{
let mut compound_body = self.open_record(None)?;
let label: &str = &compound_body.next_symbol(self)?.ok_or(error::Error::MissingItem)?;
match label {
"None" => Ok((false, compound_body)),
"Some" => Ok((true, compound_body)),
_ => Err(error::Error::Expected(ExpectedKind::Option,
Received::ReceivedRecordWithLabel(label.to_owned()))),
}
}
fn open_simple_record(&mut self, name: &'static str, arity: Option<usize>) ->
ReaderResult<CompoundBody>
where
Self: Sized
{
let mut compound_body = self.open_record(arity)?;
let label: &str = &compound_body.next_symbol(self)?.ok_or(error::Error::MissingItem)?;
if label == name {
Ok(compound_body)
} else {
Err(error::Error::Expected(ExpectedKind::SimpleRecord(name, arity),
Received::ReceivedRecordWithLabel(label.to_owned())))
}
}
}
impl<'r, 'de, R: Reader<'de>> Reader<'de> for &'r mut R {
fn next(&mut self, read_annotations: bool) -> IOResult<Option<Cow<'de, IOValue>>> {
(*self).next(read_annotations)
}
fn open_record(&mut self, arity: Option<usize>) -> ReaderResult<CompoundBody> {
(*self).open_record(arity)
}
fn open_sequence_or_set(&mut self) -> ReaderResult<CompoundBody> {
(*self).open_sequence_or_set()
}
fn open_sequence(&mut self) -> ReaderResult<CompoundBody> {
(*self).open_sequence()
}
fn open_set(&mut self) -> ReaderResult<CompoundBody> {
(*self).open_set()
}
fn open_dictionary(&mut self) -> ReaderResult<CompoundBody> {
(*self).open_dictionary()
}
fn close_compound_counted(&mut self, minor: CompoundMinor) -> ReaderResult<()> {
(*self).close_compound_counted(minor)
}
fn close_compound_stream(&mut self, minor: CompoundMinor) -> ReaderResult<bool> {
(*self).close_compound_stream(minor)
}
}
pub trait BinarySource<'de> {
fn skip(&mut self) -> IOResult<()>;
fn peek(&mut self) -> IOResult<u8>;
fn readbytes(&mut self, count: usize) -> IOResult<Cow<'de, [u8]>>;
fn readbytes_into(&mut self, bs: &mut [u8]) -> IOResult<()>;
}
pub struct IOBinarySource<'a, R: Read> {
pub read: &'a mut R,
pub buf: Option<u8>,
}
impl<'a, R: Read> IOBinarySource<'a, R> {
pub fn new(read: &'a mut R) -> Self {
IOBinarySource { read, buf: None }
}
}
impl<'de, 'a, R: Read> BinarySource<'de> for IOBinarySource<'a, R> {
fn skip(&mut self) -> IOResult<()> {
if let None = self.buf { unreachable!(); }
self.buf = None;
Ok(())
}
fn peek(&mut self) -> IOResult<u8> {
match self.buf {
Some(b) => Ok(b),
None => {
let b = &mut [0];
match self.read.read(b)? {
0 => Err(io_eof()),
1 => {
self.buf = Some(b[0]);
Ok(b[0])
}
_ => unreachable!(),
}
}
}
}
fn readbytes(&mut self, count: usize) -> IOResult<Cow<'de, [u8]>> {
if let Some(_) = self.buf { unreachable!(); }
let mut bs = vec![0; count];
self.read.read_exact(&mut bs)?;
Ok(Cow::Owned(bs))
}
fn readbytes_into(&mut self, bs: &mut [u8]) -> IOResult<()> {
if let Some(_) = self.buf { unreachable!(); }
self.read.read_exact(bs)
}
}
pub struct BytesBinarySource<'de> {
pub bytes: &'de [u8],
pub index: usize,
}
impl<'de> BytesBinarySource<'de> {
pub fn new(bytes: &'de [u8]) -> Self {
BytesBinarySource { bytes, index: 0 }
}
}
impl<'de> BinarySource<'de> for BytesBinarySource<'de> {
fn skip(&mut self) -> IOResult<()> {
if self.index >= self.bytes.len() { unreachable!(); }
self.index += 1;
Ok(())
}
fn peek(&mut self) -> IOResult<u8> {
if self.index >= self.bytes.len() {
Err(io_eof())
} else {
Ok(self.bytes[self.index])
}
}
fn readbytes(&mut self, count: usize) -> IOResult<Cow<'de, [u8]>> {
if self.index + count > self.bytes.len() {
Err(io_eof())
} else {
let bs = &self.bytes[self.index..self.index+count];
self.index += count;
Ok(Cow::Borrowed(bs))
}
}
fn readbytes_into(&mut self, bs: &mut [u8]) -> IOResult<()> {
let count = bs.len();
if self.index + count > self.bytes.len() {
Err(io_eof())
} else {
bs.copy_from_slice(&self.bytes[self.index..self.index+count]);
self.index += count;
Ok(())
}
}
}
pub struct BinaryReader<'de, S: BinarySource<'de>> {
pub source: S,
phantom: PhantomData<&'de ()>,
}
impl<'de, S: BinarySource<'de>> BinarySource<'de> for BinaryReader<'de, S> {
fn skip(&mut self) -> IOResult<()> {
self.source.skip()
}
fn peek(&mut self) -> IOResult<u8> {
self.source.peek()
}
fn readbytes(&mut self, count: usize) -> IOResult<Cow<'de, [u8]>> {
self.source.readbytes(count)
}
fn readbytes_into(&mut self, bs: &mut [u8]) -> IOResult<()> {
self.source.readbytes_into(bs)
}
}
pub fn from_bytes<'de>(bytes: &'de [u8]) ->
BinaryReader<'de, BytesBinarySource<'de>>
{
BinaryReader::new(BytesBinarySource::new(bytes))
}
pub fn from_read<'de, 'a, IOR: std::io::Read>(read: &'a mut IOR) ->
BinaryReader<'de, IOBinarySource<'a, IOR>>
{
BinaryReader::new(IOBinarySource::new(read))
}
impl<'de, S: BinarySource<'de>> BinaryReader<'de, S> {
pub fn new(source: S) -> Self {
BinaryReader { source, phantom: PhantomData }
}
fn read(&mut self) -> IOResult<u8> {
let v = self.peek()?;
self.skip()?;
Ok(v)
}
fn expected(&mut self, k: ExpectedKind) -> error::Error {
match self.demand_next(true) {
Ok(v) => error::Error::Expected(k, Received::ReceivedOtherValue(v.into_owned())),
Err(e) => e.into()
}
}
fn varint(&mut self) -> IOResult<usize> {
let v = self.read()?;
if v < 128 {
Ok(usize::from(v))
} else {
Ok(self.varint()? * 128 + usize::from(v - 128))
}
}
fn wirelength(&mut self, arg: u8) -> IOResult<usize> {
if arg < 15 {
Ok(usize::from(arg))
} else {
self.varint()
}
}
fn peekend(&mut self) -> IOResult<bool> {
if self.peek()? == 4 {
self.skip()?;
Ok(true)
} else {
Ok(false)
}
}
fn gather_chunks(&mut self) -> IOResult<Vec<u8>> {
let mut bs = Vec::with_capacity(256);
while !self.peekend()? {
match decodeop(self.peek()?)? {
(Op::Atom(AtomMinor::ByteString), arg) => {
self.skip()?;
let count = self.wirelength(arg)?;
if count == 0 {
return Err(io_syntax_error("Empty binary chunks are forbidden"));
}
bs.extend_from_slice(&self.readbytes(count)?)
},
_ => return Err(io_syntax_error("Unexpected non-format-B-ByteString chunk"))
}
}
Ok(bs)
}
fn peek_next_nonannotation_op(&mut self) -> ReaderResult<(Op, u8)> {
loop {
match decodeop(self.peek()?)? {
(Op::Misc(0), 5) => self.skip()?,
other => return Ok(other),
}
}
}
fn next_atomic(&mut self, minor: AtomMinor, k: ExpectedKind) -> ReaderResult<Cow<'de, [u8]>> {
match self.peek_next_nonannotation_op()? {
(Op::Atom(actual_minor), arg) if actual_minor == minor => {
self.skip()?;
let count = self.wirelength(arg)?;
Ok(self.readbytes(count)?)
}
(Op::Misc(2), arg) => match Op::try_from(arg)? {
Op::Atom(actual_minor) if actual_minor == minor => {
self.skip()?;
Ok(Cow::Owned(self.gather_chunks()?))
}
_ => Err(self.expected(k)),
},
_ => Err(self.expected(k)),
}
}
fn next_compound(&mut self, minor: CompoundMinor, k: ExpectedKind) ->
ReaderResult<CompoundBody>
{
match self.peek_next_nonannotation_op()? {
(Op::Compound(actual_minor), arg) if actual_minor == minor => {
self.skip()?;
Ok(CompoundBody::counted(minor, self.wirelength(arg)?))
}
(Op::Misc(2), arg) => match Op::try_from(arg)? {
Op::Compound(actual_minor) if actual_minor == minor => {
self.skip()?;
Ok(CompoundBody::streaming(minor))
}
_ => Err(self.expected(k)),
},
_ => Err(self.expected(k)),
}
}
fn next_unsigned<T: FromPrimitive, F>(&mut self, f: F) -> ReaderResult<T>
where
F: FnOnce(u64) -> Option<T>
{
match self.peek_next_nonannotation_op()? {
(Op::Misc(3), arg) => {
self.skip()?;
if arg > 12 {
Err(error::Error::NumberOutOfRange(decodeint(&[((arg as i8) - 16) as u8])))
} else {
f(arg as u64).ok_or_else(|| error::Error::NumberOutOfRange(decodeint(&[arg])))
}
}
(Op::Atom(AtomMinor::SignedInteger), arg) => {
self.skip()?;
let mut count = self.wirelength(arg)?;
if count == 0 {
return f(0).ok_or_else(|| error::Error::NumberOutOfRange(BigInt::from(0)));
}
if count > 8 {
let prefix = self.readbytes(count - 8)?;
if !(&prefix).iter().all(|b| *b == 0x00) {
let mut total = prefix.into_owned();
total.extend_from_slice(&self.readbytes(8)?);
return Err(error::Error::NumberOutOfRange(decodeint(&total)));
}
count = 8;
} else {
if (self.peek()? & 0x80) != 0 {
return Err(error::Error::NumberOutOfRange(decodeint(&self.readbytes(count)?)))
}
}
let mut bs = [0; 8];
self.readbytes_into(&mut bs[8 - count..])?;
f(u64::from_be_bytes(bs))
.ok_or_else(|| error::Error::NumberOutOfRange(decodeint(&bs)))
}
_ => {
let i_value = self.demand_next(false)?;
let i = i_value.value().to_signedinteger()?;
let n = i.to_u64().ok_or_else(|| error::Error::NumberOutOfRange(i.clone()))?;
f(n).ok_or_else(|| error::Error::NumberOutOfRange(i.clone()))
}
}
}
fn next_signed<T: FromPrimitive, F>(&mut self, f: F) -> ReaderResult<T>
where
F: FnOnce(i64) -> Option<T>
{
match self.peek_next_nonannotation_op()? {
(Op::Misc(3), arg) => {
self.skip()?;
let n = arg as i64;
let n = if n > 12 { n - 16 } else { n };
f(n).ok_or_else(|| error::Error::NumberOutOfRange(decodeint(&[n as u8])))
}
(Op::Atom(AtomMinor::SignedInteger), arg) => {
self.skip()?;
let mut count = self.wirelength(arg)?;
if count == 0 {
return f(0).ok_or_else(|| error::Error::NumberOutOfRange(BigInt::from(0)));
}
let fill_byte = if count > 8 {
let prefix = self.readbytes(count - 8)?;
let fill_byte = if (prefix[0] & 0x80) == 0 { 0x00 } else { 0xff };
if !(&prefix).iter().all(|b| *b == fill_byte) {
let mut total = prefix.into_owned();
total.extend_from_slice(&self.readbytes(8)?);
return Err(error::Error::NumberOutOfRange(decodeint(&total)));
}
count = 8;
if (self.peek()? & 0x80) != (fill_byte & 0x80) {
let mut total = vec![fill_byte];
total.extend_from_slice(&self.readbytes(8)?);
return Err(error::Error::NumberOutOfRange(decodeint(&total)));
}
fill_byte
} else {
if (self.peek()? & 0x80) == 0 { 0x00 } else { 0xff }
};
let mut bs = [fill_byte; 8];
self.readbytes_into(&mut bs[8 - count..])?;
f(i64::from_be_bytes(bs))
.ok_or_else(|| error::Error::NumberOutOfRange(decodeint(&bs)))
}
_ => {
let i_value = self.demand_next(false)?;
let i = i_value.value().to_signedinteger()?;
let n = i.to_i64().ok_or_else(|| error::Error::NumberOutOfRange(i.clone()))?;
f(n).ok_or_else(|| error::Error::NumberOutOfRange(i.clone()))
}
}
}
}
impl<'de, S: BinarySource<'de>> Reader<'de> for BinaryReader<'de, S> {
fn next(&mut self, read_annotations: bool) -> IOResult<Option<Cow<'de, IOValue>>> {
match self.peek() {
Err(e) if is_eof_io_error(&e) => return Ok(None),
Err(e) => return Err(e),
Ok(_) => (),
}
loop {
return Ok(Some(match decodeop(self.read()?)? {
(Op::Misc(0), 0) => Cow::Borrowed(&FALSE),
(Op::Misc(0), 1) => Cow::Borrowed(&TRUE),
(Op::Misc(0), 2) => {
let bs: &[u8] = &self.readbytes(4)?;
Cow::Owned(Value::from(f32::from_bits(u32::from_be_bytes(bs.try_into().unwrap()))).wrap())
}
(Op::Misc(0), 3) => {
let bs: &[u8] = &self.readbytes(8)?;
Cow::Owned(Value::from(f64::from_bits(u64::from_be_bytes(bs.try_into().unwrap()))).wrap())
}
(Op::Misc(0), 5) => {
if read_annotations {
let mut annotations = vec![self.demand_next(read_annotations)?.into_owned()];
while decodeop(self.peek()?)? == (Op::Misc(0), 5) {
self.skip()?;
annotations.push(self.demand_next(read_annotations)?.into_owned());
}
let (existing_annotations, v) = self.demand_next(read_annotations)?.into_owned().pieces();
annotations.extend(existing_annotations);
Cow::Owned(IOValue::wrap_ann(annotations, v))
} else {
self.skip_value()?;
continue;
}
}
(Op::Misc(0), _) => Err(io_syntax_error("Invalid format A encoding"))?,
(Op::Misc(1), _) => Err(io_syntax_error("Invalid format A encoding"))?,
(Op::Misc(2), arg) => match Op::try_from(arg)? {
Op::Atom(minor) =>
Cow::Owned(decodebinary(minor, Cow::Owned(self.gather_chunks()?))?),
Op::Compound(minor) => Cow::Owned(decodecompound(minor, DelimitedStream {
reader: ConfiguredBinaryReader {
reader: self,
read_annotations,
phantom: PhantomData,
},
})?),
_ => Err(io_syntax_error("Invalid format C start byte"))?,
}
(Op::Misc(3), arg) => {
let n = if arg > 12 { i32::from(arg) - 16 } else { i32::from(arg) };
// TODO: prebuild these in value.rs
Cow::Owned(Value::from(n).wrap())
}
(Op::Misc(_), _) => unreachable!(),
(Op::Atom(minor), arg) => {
let count = self.wirelength(arg)?;
Cow::Owned(decodebinary(minor, self.readbytes(count)?)?)
}
(Op::Compound(minor), arg) => {
let count = self.wirelength(arg)?;
Cow::Owned(decodecompound(minor, CountedStream {
reader: ConfiguredBinaryReader {
reader: self,
read_annotations,
phantom: PhantomData,
},
count,
})?)
}
(Op::Reserved(3), 15) => continue,
(Op::Reserved(_), _) => return Err(InvalidOp.into()),
}))
}
}
fn open_record(&mut self, arity: Option<usize>) -> ReaderResult<CompoundBody> {
if let Some(expected_arity) = arity {
let compound_format =
self.next_compound(CompoundMinor::Record, ExpectedKind::Record(arity))?;
if let CompoundLimit::Counted(count) = compound_format.limit {
if count != expected_arity + 1 /* we add 1 for the label */ {
return Err(error::Error::Expected(ExpectedKind::Record(arity),
Received::ReceivedSomethingElse));
}
}
Ok(compound_format)
} else {
self.next_compound(CompoundMinor::Record, ExpectedKind::Record(None))
}
}
fn open_sequence_or_set(&mut self) -> ReaderResult<CompoundBody> {
match self.peek_next_nonannotation_op()? {
(Op::Compound(minor), arg)
if CompoundMinor::Sequence == minor || CompoundMinor::Set == minor => {
self.skip()?;
Ok(CompoundBody::counted(minor, self.wirelength(arg)?))
}
(Op::Misc(2), arg) => match Op::try_from(arg)? {
Op::Compound(minor)
if CompoundMinor::Sequence == minor || CompoundMinor::Set == minor => {
self.skip()?;
Ok(CompoundBody::streaming(minor))
}
_ => Err(self.expected(ExpectedKind::SequenceOrSet)),
}
_ => Err(self.expected(ExpectedKind::SequenceOrSet)),
}
}
fn open_sequence(&mut self) -> ReaderResult<CompoundBody> {
self.next_compound(CompoundMinor::Sequence, ExpectedKind::Sequence)
}
fn open_set(&mut self) -> ReaderResult<CompoundBody> {
self.next_compound(CompoundMinor::Set, ExpectedKind::Set)
}
fn open_dictionary(&mut self) -> ReaderResult<CompoundBody> {
self.next_compound(CompoundMinor::Dictionary, ExpectedKind::Dictionary)
}
fn close_compound_counted(&mut self, _minor: CompoundMinor) -> ReaderResult<()> {
// Nothing to do -- no close delimiter to consume
Ok(())
}
fn close_compound_stream(&mut self, _minor: CompoundMinor) -> ReaderResult<bool> {
Ok(self.peekend()?)
}
fn next_boolean(&mut self) -> ReaderResult<bool> {
match self.peek_next_nonannotation_op()? {
(Op::Misc(0), 0) => { self.skip()?; Ok(false) }
(Op::Misc(0), 1) => { self.skip()?; Ok(true) }
_ => Err(self.expected(ExpectedKind::Boolean)),
}
}
fn next_i8(&mut self) -> ReaderResult<i8> { self.next_signed(|n| n.to_i8()) }
fn next_i16(&mut self) -> ReaderResult<i16> { self.next_signed(|n| n.to_i16()) }
fn next_i32(&mut self) -> ReaderResult<i32> { self.next_signed(|n| n.to_i32()) }
fn next_i64(&mut self) -> ReaderResult<i64> { self.next_signed(|n| Some(n)) }
fn next_u8(&mut self) -> ReaderResult<u8> { self.next_unsigned(|n| n.to_u8()) }
fn next_u16(&mut self) -> ReaderResult<u16> { self.next_unsigned(|n| n.to_u16()) }
fn next_u32(&mut self) -> ReaderResult<u32> { self.next_unsigned(|n| n.to_u32()) }
fn next_u64(&mut self) -> ReaderResult<u64> { self.next_unsigned(|n| Some(n)) }
fn next_float(&mut self) -> ReaderResult<f32> {
match self.peek_next_nonannotation_op()? {
(Op::Misc(0), 2) => {
self.skip()?;
let bs: &[u8] = &self.readbytes(4)?;
Ok(f32::from_bits(u32::from_be_bytes(bs.try_into().unwrap())))
},
(Op::Misc(0), 3) => {
self.skip()?;
let bs: &[u8] = &self.readbytes(8)?;
Ok(f64::from_bits(u64::from_be_bytes(bs.try_into().unwrap())) as f32)
},
_ => Err(self.expected(ExpectedKind::Float)),
}
}
fn next_double(&mut self) -> ReaderResult<f64> {
match self.peek_next_nonannotation_op()? {
(Op::Misc(0), 2) => {
self.skip()?;
let bs: &[u8] = &self.readbytes(4)?;
Ok(f32::from_bits(u32::from_be_bytes(bs.try_into().unwrap())) as f64)
},
(Op::Misc(0), 3) => {
self.skip()?;
let bs: &[u8] = &self.readbytes(8)?;
Ok(f64::from_bits(u64::from_be_bytes(bs.try_into().unwrap())))
},
_ => Err(self.expected(ExpectedKind::Double)),
}
}
fn next_str(&mut self) -> ReaderResult<Cow<'de, str>> {
Ok(decodestr(self.next_atomic(AtomMinor::String, ExpectedKind::Symbol)?)?)
}
fn next_bytestring(&mut self) -> ReaderResult<Cow<'de, [u8]>> {
self.next_atomic(AtomMinor::ByteString, ExpectedKind::Symbol)
}
fn next_symbol(&mut self) -> ReaderResult<Cow<'de, str>> {
Ok(decodestr(self.next_atomic(AtomMinor::Symbol, ExpectedKind::Symbol)?)?)
}
}
struct ConfiguredBinaryReader<'de, 'a, S: BinarySource<'de>> {
reader: &'a mut BinaryReader<'de, S>,
read_annotations: bool,
phantom: PhantomData<&'de ()>,
}
struct CountedStream<'de, 'a, S: BinarySource<'de>> {
reader: ConfiguredBinaryReader<'de, 'a, S>,
count: usize,
}
impl<'de, 'a, S: BinarySource<'de>> Iterator for CountedStream<'de, 'a, S>
{
type Item = IOResult<Cow<'de, IOValue>>;
fn next(&mut self) -> Option<Self::Item> {
if self.count == 0 { return None }
self.count -= 1;
Some(self.reader.reader.demand_next(self.reader.read_annotations))
}
}
struct DelimitedStream<'de, 'a, S: BinarySource<'de>> {
reader: ConfiguredBinaryReader<'de, 'a, S>,
}
impl<'de, 'a, S: BinarySource<'de>> Iterator for DelimitedStream<'de, 'a, S>
{
type Item = IOResult<Cow<'de, IOValue>>;
fn next(&mut self) -> Option<Self::Item> {
match self.reader.reader.peekend() {
Err(e) => Some(Err(e)),
Ok(true) => None,
Ok(false) => Some(self.reader.reader.demand_next(self.reader.read_annotations)),
}
}
}
pub fn decodeop(b: u8) -> IOResult<(Op, u8)> {
Ok((Op::try_from(b >> 4)?, b & 15))
}
pub fn decodeint(bs: &[u8]) -> BigInt {
BigInt::from_signed_bytes_be(bs)
}
pub fn decodestr<'de>(cow: Cow<'de, [u8]>) -> IOResult<Cow<'de, str>> {
match cow {
Cow::Borrowed(bs) =>
Ok(Cow::Borrowed(std::str::from_utf8(bs).map_err(|_| io_syntax_error("Invalid UTF-8"))?)),
Cow::Owned(bs) =>
Ok(Cow::Owned(std::str::from_utf8(&bs).map_err(|_| io_syntax_error("Invalid UTF-8"))?.to_owned())),
}
}
pub fn decodebinary<'de>(minor: AtomMinor, bs: Cow<'de, [u8]>) -> IOResult<IOValue> {
Ok(match minor {
AtomMinor::SignedInteger => Value::from(decodeint(&bs)).wrap(),
AtomMinor::String => Value::String(decodestr(bs)?.into_owned()).wrap(),
AtomMinor::ByteString => Value::ByteString(bs.into_owned()).wrap(),
AtomMinor::Symbol => Value::symbol(&decodestr(bs)?).wrap(),
})
}
pub fn decodecompound<'de, I: Iterator<Item = IOResult<Cow<'de, IOValue>>>>(
minor: CompoundMinor,
mut iter: I
) ->
IOResult<IOValue>
{
match minor {
CompoundMinor::Record =>
match iter.next() {
None => Err(io_syntax_error("Too few elements in encoded record")),
Some(labelres) => {
let label = labelres?.into_owned();
let fields = iter.map(|r| r.map(|c| c.into_owned())).collect::<IOResult<Vec<IOValue>>>()?;
Ok(Value::record(label, fields).wrap())
}
}
CompoundMinor::Sequence => {
let vs = iter.map(|r| r.map(|c| c.into_owned())).collect::<IOResult<Vec<IOValue>>>()?;
Ok(Value::Sequence(vs).wrap())
}
CompoundMinor::Set => {
let mut s = Set::new();
for res in iter { s.insert(res?.into_owned()); }
Ok(Value::Set(s).wrap())
}
CompoundMinor::Dictionary => {
let mut d = Map::new();
while let Some(kres) = iter.next() {
let k = kres?.into_owned();
match iter.next() {
Some(vres) => {
let v = vres?.into_owned();
d.insert(k, v);
}
None => return Err(io_syntax_error("Missing dictionary value")),
}
}
Ok(Value::Dictionary(d).wrap())
}
}
}