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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /vendor/miniz_oxide/src/deflate/buffer.rs
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/miniz_oxide/src/deflate/buffer.rs')
-rw-r--r--vendor/miniz_oxide/src/deflate/buffer.rs58
1 files changed, 58 insertions, 0 deletions
diff --git a/vendor/miniz_oxide/src/deflate/buffer.rs b/vendor/miniz_oxide/src/deflate/buffer.rs
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+++ b/vendor/miniz_oxide/src/deflate/buffer.rs
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+//! Buffer wrappers implementing default so we can allocate the buffers with `Box::default()`
+//! to avoid stack copies. Box::new() doesn't at the moment, and using a vec means we would lose
+//! static length info.
+
+use crate::deflate::core::{LZ_DICT_SIZE, MAX_MATCH_LEN};
+
+/// Size of the buffer of lz77 encoded data.
+pub const LZ_CODE_BUF_SIZE: usize = 64 * 1024;
+/// Size of the output buffer.
+pub const OUT_BUF_SIZE: usize = (LZ_CODE_BUF_SIZE * 13) / 10;
+pub const LZ_DICT_FULL_SIZE: usize = LZ_DICT_SIZE + MAX_MATCH_LEN - 1 + 1;
+
+/// Size of hash values in the hash chains.
+pub const LZ_HASH_BITS: i32 = 15;
+/// How many bits to shift when updating the current hash value.
+pub const LZ_HASH_SHIFT: i32 = (LZ_HASH_BITS + 2) / 3;
+/// Size of the chained hash tables.
+pub const LZ_HASH_SIZE: usize = 1 << LZ_HASH_BITS;
+
+#[inline]
+pub fn update_hash(current_hash: u16, byte: u8) -> u16 {
+ ((current_hash << LZ_HASH_SHIFT) ^ u16::from(byte)) & (LZ_HASH_SIZE as u16 - 1)
+}
+
+pub struct HashBuffers {
+ pub dict: [u8; LZ_DICT_FULL_SIZE],
+ pub next: [u16; LZ_DICT_SIZE],
+ pub hash: [u16; LZ_DICT_SIZE],
+}
+
+impl HashBuffers {
+ #[inline]
+ pub fn reset(&mut self) {
+ *self = HashBuffers::default();
+ }
+}
+
+impl Default for HashBuffers {
+ fn default() -> HashBuffers {
+ HashBuffers {
+ dict: [0; LZ_DICT_FULL_SIZE],
+ next: [0; LZ_DICT_SIZE],
+ hash: [0; LZ_DICT_SIZE],
+ }
+ }
+}
+
+pub struct LocalBuf {
+ pub b: [u8; OUT_BUF_SIZE],
+}
+
+impl Default for LocalBuf {
+ fn default() -> LocalBuf {
+ LocalBuf {
+ b: [0; OUT_BUF_SIZE],
+ }
+ }
+}