Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 197 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..bf36dcc2aa
--- /dev/null
+++ b/third_party/rust/nom/src/bits/complete.rs
@@ -0,0 +1,197 @@
+//! 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)))
+      }
+    })
+  }
+}
+
+/// Parses one specific bit as a bool.
+///
+/// # Example
+/// ```rust
+/// # use nom::bits::complete::bool;
+/// # use nom::IResult;
+/// # use nom::error::{Error, ErrorKind};
+///
+/// fn parse(input: (&[u8], usize)) -> IResult<(&[u8], usize), bool> {
+///     bool(input)
+/// }
+///
+/// assert_eq!(parse(([0b10000000].as_ref(), 0)), Ok((([0b10000000].as_ref(), 1), true)));
+/// assert_eq!(parse(([0b10000000].as_ref(), 1)), Ok((([0b10000000].as_ref(), 2), false)));
+/// ```
+pub fn bool<I, E: ParseError<(I, usize)>>(input: (I, usize)) -> IResult<(I, usize), bool, E>
+where
+  I: Slice<RangeFrom<usize>> + InputIter<Item = u8> + InputLength,
+{
+  let (res, bit): (_, u32) = take(1usize)(input)?;
+  Ok((res, bit != 0))
+}
+
+#[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))
+    );
+  }
+
+  #[test]
+  fn test_bool_0() {
+    let input = [0b10000000].as_ref();
+
+    let result: crate::IResult<(&[u8], usize), bool> = bool((input, 0));
+
+    assert_eq!(result, Ok(((input, 1), true)));
+  }
+
+  #[test]
+  fn test_bool_eof() {
+    let input = [0b10000000].as_ref();
+
+    let result: crate::IResult<(&[u8], usize), bool> = bool((input, 8));
+
+    assert_eq!(
+      result,
+      Err(crate::Err::Error(crate::error::Error {
+        input: (input, 8),
+        code: ErrorKind::Eof
+      }))
+    );
+  }
+}