From a771372ca15b35a5cd940f691f4de420ae0f76e3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Simon=20W=C3=BClker?= <simon.wuelker@arcor.de>
Date: Sat, 16 Mar 2024 23:59:43 +0100
Subject: [PATCH] compression: Use the sl-std ringbuffer implementation

---
 crates/compression/src/brotli/mod.rs |  7 +--
 crates/compression/src/lib.rs        |  1 -
 crates/compression/src/ringbuffer.rs | 79 ----------------------------
 3 files changed, 4 insertions(+), 83 deletions(-)
 delete mode 100644 crates/compression/src/ringbuffer.rs

diff --git a/crates/compression/src/brotli/mod.rs b/crates/compression/src/brotli/mod.rs
index 993ca881..e4cde6a2 100644
--- a/crates/compression/src/brotli/mod.rs
+++ b/crates/compression/src/brotli/mod.rs
@@ -5,9 +5,10 @@ pub mod dictionary;
 use crate::{
     bitreader::{self, BitReader},
     huffman::{Bits, HuffmanBitTree, HuffmanTree},
-    ringbuffer::RingBuffer,
 };
 
+use sl_std::ring_buffer::RingBuffer;
+
 use std::cmp::min;
 
 macro_rules! update_block_type_and_count {
@@ -149,7 +150,7 @@ pub fn decompress(source: &[u8]) -> Result<Vec<u8>, Error> {
     };
 
     let window_size = (1 << wbits) - 16;
-    let mut past_distances = RingBuffer::new([16, 15, 11, 4]);
+    let mut past_distances = RingBuffer::from([16, 15, 11, 4]);
 
     let mut is_last = false;
     while !is_last {
@@ -364,7 +365,7 @@ pub fn decompress(source: &[u8]) -> Result<Vec<u8>, Error> {
 
                 // Dictionary references, 0 distances and a few transformations are not pushed
                 if distance_code != 0 && distance < max_distance + 1 {
-                    past_distances.push(distance);
+                    past_distances.push_overwriting(distance);
                 }
                 distance
             };
diff --git a/crates/compression/src/lib.rs b/crates/compression/src/lib.rs
index 401f33f7..9243e10d 100644
--- a/crates/compression/src/lib.rs
+++ b/crates/compression/src/lib.rs
@@ -9,4 +9,3 @@ pub mod zlib;
 pub mod bitreader;
 pub mod gzip;
 pub mod huffman;
-pub mod ringbuffer;
diff --git a/crates/compression/src/ringbuffer.rs b/crates/compression/src/ringbuffer.rs
deleted file mode 100644
index 09217342..00000000
--- a/crates/compression/src/ringbuffer.rs
+++ /dev/null
@@ -1,79 +0,0 @@
-//! Implements a [circular buffer](https://en.wikipedia.org/wiki/Circular_buffer) which can hold a fixed number of items.
-
-#[derive(Clone, Debug)]
-pub struct RingBuffer<T, const N: usize> {
-    elements: [T; N],
-    ptr: usize,
-}
-
-impl<T, const N: usize> RingBuffer<T, N> {
-    pub fn new(elements: [T; N]) -> Self {
-        Self { elements, ptr: 0 }
-    }
-
-    #[inline]
-    pub fn size(&self) -> usize {
-        N
-    }
-
-    #[inline]
-    pub fn push(&mut self, element: T) {
-        self.elements[self.ptr] = element;
-        self.ptr += 1;
-        self.ptr %= self.size();
-    }
-
-    /// Get the nth previous element from the ringbuffer.
-    ///
-    /// Note that the index is 0-based, so `nth_last(0)` returns the element that was
-    /// last pushed. However, you may not retrieve more than `size` previous elements.
-    ///
-    /// # Panics
-    /// This function panics if `index >=  buffer size`
-    #[inline]
-    pub fn nth_last(&self, index: usize) -> &T {
-        assert!(index < self.size());
-        &self.elements[(self.ptr + self.size() - index - 1) % self.size()]
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::RingBuffer;
-
-    #[test]
-    fn test_ringbuffer() {
-        let mut buffer = RingBuffer::new([3, 2, 1]);
-
-        assert_eq!(*buffer.nth_last(0), 1);
-        assert_eq!(*buffer.nth_last(1), 2);
-        assert_eq!(*buffer.nth_last(2), 3);
-
-        buffer.push(4);
-        // Internal buffer should now look like this:
-        // [4, 2, 1]
-        //     ^_ self.ptr
-
-        assert_eq!(*buffer.nth_last(0), 4);
-        assert_eq!(*buffer.nth_last(1), 1);
-        assert_eq!(*buffer.nth_last(2), 2);
-
-        buffer.push(5);
-        // Internal buffer should now look like this:
-        // [5, 4, 1]
-        //        ^_ self.ptr
-
-        assert_eq!(*buffer.nth_last(0), 5);
-        assert_eq!(*buffer.nth_last(1), 4);
-        assert_eq!(*buffer.nth_last(2), 1);
-
-        buffer.push(6);
-        // Internal buffer should now look like this:
-        // [5, 4, 6]
-        //  ^_ self.ptr
-
-        assert_eq!(*buffer.nth_last(0), 6);
-        assert_eq!(*buffer.nth_last(1), 5);
-        assert_eq!(*buffer.nth_last(2), 4);
-    }
-}