forgejo-federation/vendor/github.com/xi2/xz/dec_delta.go
PhilippHomann 684b7a999f
Dump: add output format tar and output to stdout (#10376)
* 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>
2020-06-05 16:47:39 -04:00

55 lines
1.1 KiB
Go
Vendored

/*
* Delta decoder
*
* Author: Lasse Collin <lasse.collin@tukaani.org>
*
* Translation to Go: Michael Cross <https://github.com/xi2>
*
* This file has been put into the public domain.
* You can do whatever you want with this file.
*/
package xz
type xzDecDelta struct {
delta [256]byte
pos byte
distance int // in range [1, 256]
}
/*
* Decode raw stream which has a delta filter as the first filter.
*/
func xzDecDeltaRun(s *xzDecDelta, b *xzBuf, chain func(*xzBuf) xzRet) xzRet {
outStart := b.outPos
ret := chain(b)
for i := outStart; i < b.outPos; i++ {
tmp := b.out[i] + s.delta[byte(s.distance+int(s.pos))]
s.delta[s.pos] = tmp
b.out[i] = tmp
s.pos--
}
return ret
}
/*
* Allocate memory for a delta decoder. xzDecDeltaReset must be used
* before calling xzDecDeltaRun.
*/
func xzDecDeltaCreate() *xzDecDelta {
return new(xzDecDelta)
}
/*
* Returns xzOK if the given distance is valid. Otherwise
* xzOptionsError is returned.
*/
func xzDecDeltaReset(s *xzDecDelta, distance int) xzRet {
if distance < 1 || distance > 256 {
return xzOptionsError
}
s.delta = [256]byte{}
s.pos = 0
s.distance = distance
return xzOK
}