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-rw-r--r--third_party/rust/nom/src/bits/complete.rs150
-rw-r--r--third_party/rust/nom/src/bits/mod.rs179
-rw-r--r--third_party/rust/nom/src/bits/streaming.rs129
3 files changed, 458 insertions, 0 deletions
diff --git a/third_party/rust/nom/src/bits/complete.rs b/third_party/rust/nom/src/bits/complete.rs
new file mode 100644
index 0000000000..b46bc7a279
--- /dev/null
+++ b/third_party/rust/nom/src/bits/complete.rs
@@ -0,0 +1,150 @@
+//! Bit level parsers
+//!
+
+use crate::error::{ErrorKind, ParseError};
+use crate::internal::{Err, IResult};
+use crate::lib::std::ops::{AddAssign, Div, RangeFrom, Shl, Shr};
+use crate::traits::{InputIter, InputLength, Slice, ToUsize};
+
+/// Generates a parser taking `count` bits
+///
+/// # Example
+/// ```rust
+/// # use nom::bits::complete::take;
+/// # use nom::IResult;
+/// # use nom::error::{Error, ErrorKind};
+/// // Input is a tuple of (input: I, bit_offset: usize)
+/// fn parser(input: (&[u8], usize), count: usize)-> IResult<(&[u8], usize), u8> {
+/// take(count)(input)
+/// }
+///
+/// // Consumes 0 bits, returns 0
+/// assert_eq!(parser(([0b00010010].as_ref(), 0), 0), Ok((([0b00010010].as_ref(), 0), 0)));
+///
+/// // Consumes 4 bits, returns their values and increase offset to 4
+/// assert_eq!(parser(([0b00010010].as_ref(), 0), 4), Ok((([0b00010010].as_ref(), 4), 0b00000001)));
+///
+/// // Consumes 4 bits, offset is 4, returns their values and increase offset to 0 of next byte
+/// assert_eq!(parser(([0b00010010].as_ref(), 4), 4), Ok((([].as_ref(), 0), 0b00000010)));
+///
+/// // Tries to consume 12 bits but only 8 are available
+/// assert_eq!(parser(([0b00010010].as_ref(), 0), 12), Err(nom::Err::Error(Error{input: ([0b00010010].as_ref(), 0), code: ErrorKind::Eof })));
+/// ```
+pub fn take<I, O, C, E: ParseError<(I, usize)>>(
+ count: C,
+) -> impl Fn((I, usize)) -> IResult<(I, usize), O, E>
+where
+ I: Slice<RangeFrom<usize>> + InputIter<Item = u8> + InputLength,
+ C: ToUsize,
+ O: From<u8> + AddAssign + Shl<usize, Output = O> + Shr<usize, Output = O>,
+{
+ let count = count.to_usize();
+ move |(input, bit_offset): (I, usize)| {
+ if count == 0 {
+ Ok(((input, bit_offset), 0u8.into()))
+ } else {
+ let cnt = (count + bit_offset).div(8);
+ if input.input_len() * 8 < count + bit_offset {
+ Err(Err::Error(E::from_error_kind(
+ (input, bit_offset),
+ ErrorKind::Eof,
+ )))
+ } else {
+ let mut acc: O = 0_u8.into();
+ let mut offset: usize = bit_offset;
+ let mut remaining: usize = count;
+ let mut end_offset: usize = 0;
+
+ for byte in input.iter_elements().take(cnt + 1) {
+ if remaining == 0 {
+ break;
+ }
+ let val: O = if offset == 0 {
+ byte.into()
+ } else {
+ ((byte << offset) as u8 >> offset).into()
+ };
+
+ if remaining < 8 - offset {
+ acc += val >> (8 - offset - remaining);
+ end_offset = remaining + offset;
+ break;
+ } else {
+ acc += val << (remaining - (8 - offset));
+ remaining -= 8 - offset;
+ offset = 0;
+ }
+ }
+ Ok(((input.slice(cnt..), end_offset), acc))
+ }
+ }
+ }
+}
+
+/// Generates a parser taking `count` bits and comparing them to `pattern`
+pub fn tag<I, O, C, E: ParseError<(I, usize)>>(
+ pattern: O,
+ count: C,
+) -> impl Fn((I, usize)) -> IResult<(I, usize), O, E>
+where
+ I: Slice<RangeFrom<usize>> + InputIter<Item = u8> + InputLength + Clone,
+ C: ToUsize,
+ O: From<u8> + AddAssign + Shl<usize, Output = O> + Shr<usize, Output = O> + PartialEq,
+{
+ let count = count.to_usize();
+ move |input: (I, usize)| {
+ let inp = input.clone();
+
+ take(count)(input).and_then(|(i, o)| {
+ if pattern == o {
+ Ok((i, o))
+ } else {
+ Err(Err::Error(error_position!(inp, ErrorKind::TagBits)))
+ }
+ })
+ }
+}
+
+#[cfg(test)]
+mod test {
+ use super::*;
+
+ #[test]
+ fn test_take_0() {
+ let input = [0b00010010].as_ref();
+ let count = 0usize;
+ assert_eq!(count, 0usize);
+ let offset = 0usize;
+
+ let result: crate::IResult<(&[u8], usize), usize> = take(count)((input, offset));
+
+ assert_eq!(result, Ok(((input, offset), 0)));
+ }
+
+ #[test]
+ fn test_take_eof() {
+ let input = [0b00010010].as_ref();
+
+ let result: crate::IResult<(&[u8], usize), usize> = take(1usize)((input, 8));
+
+ assert_eq!(
+ result,
+ Err(crate::Err::Error(crate::error::Error {
+ input: (input, 8),
+ code: ErrorKind::Eof
+ }))
+ )
+ }
+
+ #[test]
+ fn test_take_span_over_multiple_bytes() {
+ let input = [0b00010010, 0b00110100, 0b11111111, 0b11111111].as_ref();
+
+ let result: crate::IResult<(&[u8], usize), usize> = take(24usize)((input, 4));
+
+ assert_eq!(
+ result,
+ Ok((([0b11111111].as_ref(), 4), 0b1000110100111111111111))
+ );
+ }
+}
diff --git a/third_party/rust/nom/src/bits/mod.rs b/third_party/rust/nom/src/bits/mod.rs
new file mode 100644
index 0000000000..235b7973e1
--- /dev/null
+++ b/third_party/rust/nom/src/bits/mod.rs
@@ -0,0 +1,179 @@
+//! Bit level parsers
+//!
+
+pub mod complete;
+pub mod streaming;
+
+use crate::error::{ErrorKind, ParseError};
+use crate::internal::{Err, IResult, Needed};
+use crate::lib::std::ops::RangeFrom;
+use crate::traits::{ErrorConvert, Slice};
+
+/// Converts a byte-level input to a bit-level input, for consumption by a parser that uses bits.
+///
+/// Afterwards, the input is converted back to a byte-level parser, with any remaining bits thrown
+/// away.
+///
+/// # Example
+/// ```
+/// use nom::bits::{bits, streaming::take};
+/// use nom::error::Error;
+/// use nom::sequence::tuple;
+/// use nom::IResult;
+///
+/// fn parse(input: &[u8]) -> IResult<&[u8], (u8, u8)> {
+/// bits::<_, _, Error<(&[u8], usize)>, _, _>(tuple((take(4usize), take(8usize))))(input)
+/// }
+///
+/// let input = &[0x12, 0x34, 0xff, 0xff];
+///
+/// let output = parse(input).expect("We take 1.5 bytes and the input is longer than 2 bytes");
+///
+/// // The first byte is consumed, the second byte is partially consumed and dropped.
+/// let remaining = output.0;
+/// assert_eq!(remaining, [0xff, 0xff]);
+///
+/// let parsed = output.1;
+/// assert_eq!(parsed.0, 0x01);
+/// assert_eq!(parsed.1, 0x23);
+/// ```
+pub fn bits<I, O, E1, E2, P>(mut parser: P) -> impl FnMut(I) -> IResult<I, O, E2>
+where
+ E1: ParseError<(I, usize)> + ErrorConvert<E2>,
+ E2: ParseError<I>,
+ I: Slice<RangeFrom<usize>>,
+ P: FnMut((I, usize)) -> IResult<(I, usize), O, E1>,
+{
+ move |input: I| match parser((input, 0)) {
+ Ok(((rest, offset), result)) => {
+ // If the next byte has been partially read, it will be sliced away as well.
+ // The parser functions might already slice away all fully read bytes.
+ // That's why `offset / 8` isn't necessarily needed at all times.
+ let remaining_bytes_index = offset / 8 + if offset % 8 == 0 { 0 } else { 1 };
+ Ok((rest.slice(remaining_bytes_index..), result))
+ }
+ Err(Err::Incomplete(n)) => Err(Err::Incomplete(n.map(|u| u.get() / 8 + 1))),
+ Err(Err::Error(e)) => Err(Err::Error(e.convert())),
+ Err(Err::Failure(e)) => Err(Err::Failure(e.convert())),
+ }
+}
+
+/// Counterpart to `bits`, `bytes` transforms its bit stream input into a byte slice for the underlying
+/// parser, allowing byte-slice parsers to work on bit streams.
+///
+/// A partial byte remaining in the input will be ignored and the given parser will start parsing
+/// at the next full byte.
+///
+/// ```
+/// use nom::bits::{bits, bytes, streaming::take};
+/// use nom::combinator::rest;
+/// use nom::error::Error;
+/// use nom::sequence::tuple;
+/// use nom::IResult;
+///
+/// fn parse(input: &[u8]) -> IResult<&[u8], (u8, u8, &[u8])> {
+/// bits::<_, _, Error<(&[u8], usize)>, _, _>(tuple((
+/// take(4usize),
+/// take(8usize),
+/// bytes::<_, _, Error<&[u8]>, _, _>(rest)
+/// )))(input)
+/// }
+///
+/// let input = &[0x12, 0x34, 0xff, 0xff];
+///
+/// assert_eq!(parse( input ), Ok(( &[][..], (0x01, 0x23, &[0xff, 0xff][..]) )));
+/// ```
+pub fn bytes<I, O, E1, E2, P>(mut parser: P) -> impl FnMut((I, usize)) -> IResult<(I, usize), O, E2>
+where
+ E1: ParseError<I> + ErrorConvert<E2>,
+ E2: ParseError<(I, usize)>,
+ I: Slice<RangeFrom<usize>> + Clone,
+ P: FnMut(I) -> IResult<I, O, E1>,
+{
+ move |(input, offset): (I, usize)| {
+ let inner = if offset % 8 != 0 {
+ input.slice((1 + offset / 8)..)
+ } else {
+ input.slice((offset / 8)..)
+ };
+ let i = (input, offset);
+ match parser(inner) {
+ Ok((rest, res)) => Ok(((rest, 0), res)),
+ Err(Err::Incomplete(Needed::Unknown)) => Err(Err::Incomplete(Needed::Unknown)),
+ Err(Err::Incomplete(Needed::Size(sz))) => Err(match sz.get().checked_mul(8) {
+ Some(v) => Err::Incomplete(Needed::new(v)),
+ None => Err::Failure(E2::from_error_kind(i, ErrorKind::TooLarge)),
+ }),
+ Err(Err::Error(e)) => Err(Err::Error(e.convert())),
+ Err(Err::Failure(e)) => Err(Err::Failure(e.convert())),
+ }
+ }
+}
+
+#[cfg(test)]
+mod test {
+ use super::*;
+ use crate::bits::streaming::take;
+ use crate::error::Error;
+ use crate::sequence::tuple;
+
+ #[test]
+ /// Take the `bits` function and assert that remaining bytes are correctly returned, if the
+ /// previous bytes are fully consumed
+ fn test_complete_byte_consumption_bits() {
+ let input = &[0x12, 0x34, 0x56, 0x78];
+
+ // Take 3 bit slices with sizes [4, 8, 4].
+ let result: IResult<&[u8], (u8, u8, u8)> =
+ bits::<_, _, Error<(&[u8], usize)>, _, _>(tuple((take(4usize), take(8usize), take(4usize))))(
+ input,
+ );
+
+ let output = result.expect("We take 2 bytes and the input is longer than 2 bytes");
+
+ let remaining = output.0;
+ assert_eq!(remaining, [0x56, 0x78]);
+
+ let parsed = output.1;
+ assert_eq!(parsed.0, 0x01);
+ assert_eq!(parsed.1, 0x23);
+ assert_eq!(parsed.2, 0x04);
+ }
+
+ #[test]
+ /// Take the `bits` function and assert that remaining bytes are correctly returned, if the
+ /// previous bytes are NOT fully consumed. Partially consumed bytes are supposed to be dropped.
+ /// I.e. if we consume 1.5 bytes of 4 bytes, 2 bytes will be returned, bits 13-16 will be
+ /// dropped.
+ fn test_partial_byte_consumption_bits() {
+ let input = &[0x12, 0x34, 0x56, 0x78];
+
+ // Take bit slices with sizes [4, 8].
+ let result: IResult<&[u8], (u8, u8)> =
+ bits::<_, _, Error<(&[u8], usize)>, _, _>(tuple((take(4usize), take(8usize))))(input);
+
+ let output = result.expect("We take 1.5 bytes and the input is longer than 2 bytes");
+
+ let remaining = output.0;
+ assert_eq!(remaining, [0x56, 0x78]);
+
+ let parsed = output.1;
+ assert_eq!(parsed.0, 0x01);
+ assert_eq!(parsed.1, 0x23);
+ }
+
+ #[test]
+ #[cfg(feature = "std")]
+ /// Ensure that in Incomplete error is thrown, if too few bytes are passed for a given parser.
+ fn test_incomplete_bits() {
+ let input = &[0x12];
+
+ // Take bit slices with sizes [4, 8].
+ let result: IResult<&[u8], (u8, u8)> =
+ bits::<_, _, Error<(&[u8], usize)>, _, _>(tuple((take(4usize), take(8usize))))(input);
+
+ assert!(result.is_err());
+ let error = result.err().unwrap();
+ assert_eq!("Parsing requires 2 bytes/chars", error.to_string());
+ }
+}
diff --git a/third_party/rust/nom/src/bits/streaming.rs b/third_party/rust/nom/src/bits/streaming.rs
new file mode 100644
index 0000000000..e8adc1c0d4
--- /dev/null
+++ b/third_party/rust/nom/src/bits/streaming.rs
@@ -0,0 +1,129 @@
+//! Bit level parsers
+//!
+
+use crate::error::{ErrorKind, ParseError};
+use crate::internal::{Err, IResult, Needed};
+use crate::lib::std::ops::{AddAssign, Div, RangeFrom, Shl, Shr};
+use crate::traits::{InputIter, InputLength, Slice, ToUsize};
+
+/// Generates a parser taking `count` bits
+pub fn take<I, O, C, E: ParseError<(I, usize)>>(
+ count: C,
+) -> impl Fn((I, usize)) -> IResult<(I, usize), O, E>
+where
+ I: Slice<RangeFrom<usize>> + InputIter<Item = u8> + InputLength,
+ C: ToUsize,
+ O: From<u8> + AddAssign + Shl<usize, Output = O> + Shr<usize, Output = O>,
+{
+ let count = count.to_usize();
+ move |(input, bit_offset): (I, usize)| {
+ if count == 0 {
+ Ok(((input, bit_offset), 0u8.into()))
+ } else {
+ let cnt = (count + bit_offset).div(8);
+ if input.input_len() * 8 < count + bit_offset {
+ Err(Err::Incomplete(Needed::new(count as usize)))
+ } else {
+ let mut acc: O = 0_u8.into();
+ let mut offset: usize = bit_offset;
+ let mut remaining: usize = count;
+ let mut end_offset: usize = 0;
+
+ for byte in input.iter_elements().take(cnt + 1) {
+ if remaining == 0 {
+ break;
+ }
+ let val: O = if offset == 0 {
+ byte.into()
+ } else {
+ ((byte << offset) as u8 >> offset).into()
+ };
+
+ if remaining < 8 - offset {
+ acc += val >> (8 - offset - remaining);
+ end_offset = remaining + offset;
+ break;
+ } else {
+ acc += val << (remaining - (8 - offset));
+ remaining -= 8 - offset;
+ offset = 0;
+ }
+ }
+ Ok(((input.slice(cnt..), end_offset), acc))
+ }
+ }
+ }
+}
+
+/// Generates a parser taking `count` bits and comparing them to `pattern`
+pub fn tag<I, O, C, E: ParseError<(I, usize)>>(
+ pattern: O,
+ count: C,
+) -> impl Fn((I, usize)) -> IResult<(I, usize), O, E>
+where
+ I: Slice<RangeFrom<usize>> + InputIter<Item = u8> + InputLength + Clone,
+ C: ToUsize,
+ O: From<u8> + AddAssign + Shl<usize, Output = O> + Shr<usize, Output = O> + PartialEq,
+{
+ let count = count.to_usize();
+ move |input: (I, usize)| {
+ let inp = input.clone();
+
+ take(count)(input).and_then(|(i, o)| {
+ if pattern == o {
+ Ok((i, o))
+ } else {
+ Err(Err::Error(error_position!(inp, ErrorKind::TagBits)))
+ }
+ })
+ }
+}
+
+#[cfg(test)]
+mod test {
+ use super::*;
+
+ #[test]
+ fn test_take_0() {
+ let input = [].as_ref();
+ let count = 0usize;
+ assert_eq!(count, 0usize);
+ let offset = 0usize;
+
+ let result: crate::IResult<(&[u8], usize), usize> = take(count)((input, offset));
+
+ assert_eq!(result, Ok(((input, offset), 0)));
+ }
+
+ #[test]
+ fn test_tag_ok() {
+ let input = [0b00011111].as_ref();
+ let offset = 0usize;
+ let bits_to_take = 4usize;
+ let value_to_tag = 0b0001;
+
+ let result: crate::IResult<(&[u8], usize), usize> =
+ tag(value_to_tag, bits_to_take)((input, offset));
+
+ assert_eq!(result, Ok(((input, bits_to_take), value_to_tag)));
+ }
+
+ #[test]
+ fn test_tag_err() {
+ let input = [0b00011111].as_ref();
+ let offset = 0usize;
+ let bits_to_take = 4usize;
+ let value_to_tag = 0b1111;
+
+ let result: crate::IResult<(&[u8], usize), usize> =
+ tag(value_to_tag, bits_to_take)((input, offset));
+
+ assert_eq!(
+ result,
+ Err(crate::Err::Error(crate::error::Error {
+ input: (input, offset),
+ code: ErrorKind::TagBits
+ }))
+ );
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-12 03:16:13 +0000