forked from Shiloh/githaven
684b7a999f
* Dump: Use mholt/archive/v3 to support tar including many compressions Signed-off-by: Philipp Homann <homann.philipp@googlemail.com> * Dump: Allow dump output to stdout Signed-off-by: Philipp Homann <homann.philipp@googlemail.com> * Dump: Fixed bug present since #6677 where SessionConfig.Provider is never "file" Signed-off-by: Philipp Homann <homann.philipp@googlemail.com> * Dump: never pack RepoRootPath, LFS.ContentPath and LogRootPath when they are below AppDataPath Signed-off-by: Philipp Homann <homann.philipp@googlemail.com> * Dump: also dump LFS (fixes #10058) Signed-off-by: Philipp Homann <homann.philipp@googlemail.com> * Dump: never dump CustomPath if CustomPath is a subdir of or equal to AppDataPath (fixes #10365) Signed-off-by: Philipp Homann <homann.philipp@googlemail.com> * Use log.Info instead of fmt.Fprintf Signed-off-by: Philipp Homann <homann.philipp@googlemail.com> * import ordering * make fmt Co-authored-by: zeripath <art27@cantab.net> Co-authored-by: techknowlogick <techknowlogick@gitea.io> Co-authored-by: Matti R <matti@mdranta.net>
46 lines
1.1 KiB
Go
46 lines
1.1 KiB
Go
// Copyright 2014-2017 Ulrich Kunitz. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package lzma
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/* Naming conventions follows the CodeReviewComments in the Go Wiki. */
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// ntz32Const is used by the functions NTZ and NLZ.
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const ntz32Const = 0x04d7651f
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// ntz32Table is a helper table for de Bruijn algorithm by Danny Dubé.
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// See Henry S. Warren, Jr. "Hacker's Delight" section 5-1 figure 5-26.
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var ntz32Table = [32]int8{
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0, 1, 2, 24, 3, 19, 6, 25,
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22, 4, 20, 10, 16, 7, 12, 26,
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31, 23, 18, 5, 21, 9, 15, 11,
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30, 17, 8, 14, 29, 13, 28, 27,
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}
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// ntz32 computes the number of trailing zeros for an unsigned 32-bit integer.
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func ntz32(x uint32) int {
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if x == 0 {
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return 32
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}
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x = (x & -x) * ntz32Const
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return int(ntz32Table[x>>27])
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}
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// nlz32 computes the number of leading zeros for an unsigned 32-bit integer.
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func nlz32(x uint32) int {
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// Smear left most bit to the right
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x |= x >> 1
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x |= x >> 2
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x |= x >> 4
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x |= x >> 8
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x |= x >> 16
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// Use ntz mechanism to calculate nlz.
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x++
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if x == 0 {
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return 0
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}
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x *= ntz32Const
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return 32 - int(ntz32Table[x>>27])
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}
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