open-vault/vendor/github.com/ulikunitz/xz/lzma/prob.go
Calvin Leung Huang d2dbb8c963
Vault Debug (#7375)
* cli: initial work on debug; server-status target

* debug: add metrics capture target (#7376)

* check against DR secondary

* debug: add compression

* refactor check into preflight func

* debug: set short test time on tests, fix exit code bug

* debug: use temp dir for output on tests

* debug: use mholt/archiver for compression

* first pass on adding pprof

* use logger for output

* refactor polling target capture logic

* debug: poll and collect replication status

* debug: poll and collect host-info; rename output files and collection refactor

* fix comments

* add archive test; fix bugs found

* rename flag name to singular target

* add target output test; scaffold other tests cases

* debug/test: add pprof and index file tests

* debug/test: add min timing check tests

* debug: fix index gen race and collection goroutine race

* debug: extend archive tests, handle race between program exit and polling goroutines

* update docstring

* debug: correctly add to pollingWg

* debug: add config target support

* debug: don't wait on interrupt shutdown; add file exists unit tests

* move pprof bits into its goroutine

* debug: skip empty metrics and some pprof file creation if permission denied, add matching unit test

* address comments and feedback

* Vault debug using run.Group (#7658)

* debug: switch to use oklog/run.Group

* debug: use context to cancel requests and interrupt rungroups.

* debug: trigger the first interval properly

* debug: metrics collection should use metrics interval

* debug: add missing continue on metrics error

* debug: remove the use of buffered chan to trigger first interval

* debug: don't shadow BaseCommand's client, properly block on interval capture failures

* debug: actually use c.cachedClient everywhere

* go mod vendor

* debug: run all pprof in goroutines; bump pprof timings in tests to reduce flakiness

* debug: update help text
2019-10-15 15:39:19 -07:00

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1.5 KiB
Go

// Copyright 2014-2017 Ulrich Kunitz. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package lzma
// movebits defines the number of bits used for the updates of probability
// values.
const movebits = 5
// probbits defines the number of bits of a probability value.
const probbits = 11
// probInit defines 0.5 as initial value for prob values.
const probInit prob = 1 << (probbits - 1)
// Type prob represents probabilities. The type can also be used to encode and
// decode single bits.
type prob uint16
// Dec decreases the probability. The decrease is proportional to the
// probability value.
func (p *prob) dec() {
*p -= *p >> movebits
}
// Inc increases the probability. The Increase is proportional to the
// difference of 1 and the probability value.
func (p *prob) inc() {
*p += ((1 << probbits) - *p) >> movebits
}
// Computes the new bound for a given range using the probability value.
func (p prob) bound(r uint32) uint32 {
return (r >> probbits) * uint32(p)
}
// Bits returns 1. One is the number of bits that can be encoded or decoded
// with a single prob value.
func (p prob) Bits() int {
return 1
}
// Encode encodes the least-significant bit of v. Note that the p value will be
// changed.
func (p *prob) Encode(e *rangeEncoder, v uint32) error {
return e.EncodeBit(v, p)
}
// Decode decodes a single bit. Note that the p value will change.
func (p *prob) Decode(d *rangeDecoder) (v uint32, err error) {
return d.DecodeBit(p)
}