diff options
| author | Mistivia <i@mistivia.com> | 2025-11-02 15:27:18 +0800 |
|---|---|---|
| committer | Mistivia <i@mistivia.com> | 2025-11-02 15:27:18 +0800 |
| commit | e9c24f4af7ed56760f6db7941827d09f6db9020b (patch) | |
| tree | 62128c43b883ce5e3148113350978755779bb5de /teleirc/matterbridge/vendor/github.com/klauspost/compress/zstd/hash.go | |
| parent | 58d5e7cfda4781d8a57ec52aefd02983835c301a (diff) | |
add matterbridge
Diffstat (limited to 'teleirc/matterbridge/vendor/github.com/klauspost/compress/zstd/hash.go')
| -rw-r--r-- | teleirc/matterbridge/vendor/github.com/klauspost/compress/zstd/hash.go | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/teleirc/matterbridge/vendor/github.com/klauspost/compress/zstd/hash.go b/teleirc/matterbridge/vendor/github.com/klauspost/compress/zstd/hash.go new file mode 100644 index 0000000..5d73c21 --- /dev/null +++ b/teleirc/matterbridge/vendor/github.com/klauspost/compress/zstd/hash.go @@ -0,0 +1,35 @@ +// Copyright 2019+ Klaus Post. All rights reserved. +// License information can be found in the LICENSE file. +// Based on work by Yann Collet, released under BSD License. + +package zstd + +const ( + prime3bytes = 506832829 + prime4bytes = 2654435761 + prime5bytes = 889523592379 + prime6bytes = 227718039650203 + prime7bytes = 58295818150454627 + prime8bytes = 0xcf1bbcdcb7a56463 +) + +// hashLen returns a hash of the lowest mls bytes of with length output bits. +// mls must be >=3 and <=8. Any other value will return hash for 4 bytes. +// length should always be < 32. +// Preferably length and mls should be a constant for inlining. +func hashLen(u uint64, length, mls uint8) uint32 { + switch mls { + case 3: + return (uint32(u<<8) * prime3bytes) >> (32 - length) + case 5: + return uint32(((u << (64 - 40)) * prime5bytes) >> (64 - length)) + case 6: + return uint32(((u << (64 - 48)) * prime6bytes) >> (64 - length)) + case 7: + return uint32(((u << (64 - 56)) * prime7bytes) >> (64 - length)) + case 8: + return uint32((u * prime8bytes) >> (64 - length)) + default: + return (uint32(u) * prime4bytes) >> (32 - length) + } +} |
