zenoh-protocol-core 0.7.0-rc

//
// Copyright (c) 2022 ZettaScale Technology
//
// This program and the accompanying materials are made available under the
// terms of the Eclipse Public License 2.0 which is available at
// http://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
// which is available at https://www.apache.org/licenses/LICENSE-2.0.
//
// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
//
// Contributors:
//   ZettaScale Zenoh Team, <zenoh@zettascale.tech>
//

pub(crate) struct Writer {
    pub ptr: *mut u8,
    pub len: usize,
}
impl Writer {
    pub(crate) fn write(&mut self, slice: &[u8]) {
        let len = slice.len();
        unsafe { std::ptr::copy(slice.as_ptr(), self.ptr.add(self.len), len) };
        self.len += len
    }
    pub(crate) fn write_byte(&mut self, byte: u8) {
        unsafe { *self.ptr.add(self.len) = byte };
        self.len += 1
    }
}

#[derive(Debug)]
pub struct Splitter<'a, S: ?Sized, D: ?Sized> {
    s: Option<&'a S>,
    d: &'a D,
}
impl<'a, S: ?Sized, D: ?Sized> Clone for Splitter<'a, S, D> {
    fn clone(&self) -> Self {
        Self {
            s: self.s,
            d: self.d,
        }
    }
}

impl<'a, S: Split<D> + ?Sized + std::fmt::Debug, D: ?Sized> Splitter<'a, S, D> {
    pub fn inner(&self) -> Option<&'a S> {
        self.s
    }
    pub fn unwrap(self) -> &'a S {
        self.s.unwrap()
    }
    #[allow(dead_code)]
    pub fn is_empty(&self) -> bool {
        self.s.is_none()
    }
    pub fn left(&mut self) -> Option<&'a S> {
        match self.s {
            Some(s) => match s.try_split_once(self.d) {
                (l, Some(r)) => {
                    self.s = Some(r);
                    Some(l)
                }
                _ => None,
            },
            None => None,
        }
    }
    pub fn right(&mut self) -> Option<&'a S> {
        match self.s {
            Some(s) => match s.try_rsplit_once(self.d) {
                (Some(l), r) => {
                    self.s = Some(l);
                    Some(r)
                }
                _ => None,
            },
            None => None,
        }
    }
}
impl<'a, S: Split<D> + ?Sized, D: ?Sized> Iterator for Splitter<'a, S, D> {
    type Item = &'a S;
    fn next(&mut self) -> Option<Self::Item> {
        match self.s {
            Some(s) => {
                let (ret, s) = s.try_split_once(self.d);
                self.s = s;
                Some(ret)
            }
            None => None,
        }
    }
}
#[test]
fn splits() {
    assert_eq!(
        b"hello**".splitter(b"**".as_ref()).right(),
        Some(b"".as_ref())
    );
}
impl<'a, S: Split<D> + ?Sized, D: ?Sized> DoubleEndedIterator for Splitter<'a, S, D> {
    fn next_back(&mut self) -> Option<Self::Item> {
        match self.s {
            Some(s) => {
                let (s, ret) = s.try_rsplit_once(self.d);
                self.s = s;
                Some(ret)
            }
            None => None,
        }
    }
}
pub trait Split<Delimiter: ?Sized> {
    fn split_once<'a>(&'a self, delimiter: &Delimiter) -> (&'a Self, &'a Self);
    fn try_split_once<'a>(&'a self, delimiter: &Delimiter) -> (&'a Self, Option<&'a Self>);
    fn rsplit_once<'a>(&'a self, delimiter: &Delimiter) -> (&'a Self, &'a Self);
    fn try_rsplit_once<'a>(&'a self, delimiter: &Delimiter) -> (Option<&'a Self>, &'a Self);
    fn splitter<'a>(&'a self, delimiter: &'a Delimiter) -> Splitter<'a, Self, Delimiter> {
        Splitter {
            s: Some(self),
            d: delimiter,
        }
    }
}
impl Split<u8> for [u8] {
    fn split_once<'a>(&'a self, delimiter: &u8) -> (&'a Self, &'a Self) {
        match self.iter().position(|c| c == delimiter) {
            Some(i) => (&self[..i], &self[(i + 1)..]),
            None => (self, &[]),
        }
    }
    fn rsplit_once<'a>(&'a self, delimiter: &u8) -> (&'a Self, &'a Self) {
        match self.iter().rposition(|c| c == delimiter) {
            Some(i) => (&self[..i], &self[(i + 1)..]),
            None => (&[], self),
        }
    }

    fn try_split_once<'a>(&'a self, delimiter: &u8) -> (&'a Self, Option<&'a Self>) {
        match self.iter().position(|c| c == delimiter) {
            Some(i) => (&self[..i], Some(&self[(i + 1)..])),
            None => (self, None),
        }
    }

    fn try_rsplit_once<'a>(&'a self, delimiter: &u8) -> (Option<&'a Self>, &'a Self) {
        match self.iter().rposition(|c| c == delimiter) {
            Some(i) => (Some(&self[..i]), &self[(i + 1)..]),
            None => (None, self),
        }
    }
}
impl Split<[u8]> for [u8] {
    fn split_once<'a>(&'a self, delimiter: &[u8]) -> (&'a Self, &'a Self) {
        for i in 0..self.len() {
            if self[i..].starts_with(delimiter) {
                return (&self[..i], &self[(i + delimiter.len())..]);
            }
        }
        (self, &[])
    }
    fn rsplit_once<'a>(&'a self, delimiter: &[u8]) -> (&'a Self, &'a Self) {
        for i in (0..self.len()).rev() {
            if self[..i].ends_with(delimiter) {
                return (&self[..(i - delimiter.len())], &self[i..]);
            }
        }
        (&[], self)
    }

    fn try_split_once<'a>(&'a self, delimiter: &[u8]) -> (&'a Self, Option<&'a Self>) {
        for i in 0..self.len() {
            if self[i..].starts_with(delimiter) {
                return (&self[..i], Some(&self[(i + delimiter.len())..]));
            }
        }
        (self, None)
    }

    fn try_rsplit_once<'a>(&'a self, delimiter: &[u8]) -> (Option<&'a Self>, &'a Self) {
        for i in (delimiter.len()..(self.len() + 1)).rev() {
            if self[..i].ends_with(delimiter) {
                return (Some(&self[..(i - delimiter.len())]), &self[i..]);
            }
        }
        (None, self)
    }
}
impl<const N: usize> Split<[u8; N]> for [u8] {
    fn split_once<'a>(&'a self, delimiter: &[u8; N]) -> (&'a Self, &'a Self) {
        for i in 0..self.len() {
            if self[i..].starts_with(delimiter) {
                return (&self[..i], &self[(i + delimiter.len())..]);
            }
        }
        (self, &[])
    }
    fn rsplit_once<'a>(&'a self, delimiter: &[u8; N]) -> (&'a Self, &'a Self) {
        for i in (0..self.len()).rev() {
            if self[..i].ends_with(delimiter) {
                return (&self[..(i - delimiter.len())], &self[i..]);
            }
        }
        (&[], self)
    }

    fn try_split_once<'a>(&'a self, delimiter: &[u8; N]) -> (&'a Self, Option<&'a Self>) {
        for i in 0..self.len() {
            if self[i..].starts_with(delimiter) {
                return (&self[..i], Some(&self[(i + delimiter.len())..]));
            }
        }
        (self, None)
    }

    fn try_rsplit_once<'a>(&'a self, delimiter: &[u8; N]) -> (Option<&'a Self>, &'a Self) {
        for i in (delimiter.len()..(self.len() + 1)).rev() {
            if self[..i].ends_with(delimiter) {
                return (Some(&self[..(i - delimiter.len())]), &self[i..]);
            }
        }
        (None, self)
    }
}

pub(crate) trait Utf {
    fn utf(&self) -> &str;
}
impl Utf for [u8] {
    fn utf(&self) -> &str {
        unsafe { std::str::from_utf8_unchecked(self) }
    }
}
/// This macro is generally useful when introducing new matchers to debug them.
#[allow(unused_macros)]
macro_rules! utfdbg {
    ($x: expr) => {{
        let x = $x;
        println!(
            "[{}:{}] {} = {}",
            file!(),
            line!(),
            stringify!($x),
            $crate::key_expr::utils::Utf::utf(x)
        );
        x
    }};
}