forgejo/vendor/google.golang.org/protobuf/internal/detrand/rand.go
6543 792b4dba2c
[Vendor] Update directly used dependencys (#15593)
* update github.com/blevesearch/bleve v2.0.2 -> v2.0.3

* github.com/denisenkom/go-mssqldb v0.9.0 -> v0.10.0

* github.com/editorconfig/editorconfig-core-go v2.4.1 -> v2.4.2

* github.com/go-chi/cors v1.1.1 -> v1.2.0

* github.com/go-git/go-billy v5.0.0 -> v5.1.0

* github.com/go-git/go-git v5.2.0 -> v5.3.0

* github.com/go-ldap/ldap v3.2.4 -> v3.3.0

* github.com/go-redis/redis v8.6.0 -> v8.8.2

* github.com/go-sql-driver/mysql v1.5.0 -> v1.6.0

* github.com/go-swagger/go-swagger v0.26.1 -> v0.27.0

* github.com/lib/pq v1.9.0 -> v1.10.1

* github.com/mattn/go-sqlite3 v1.14.6 -> v1.14.7

* github.com/go-testfixtures/testfixtures v3.5.0 -> v3.6.0

* github.com/issue9/identicon v1.0.1 -> v1.2.0

* github.com/klauspost/compress v1.11.8 -> v1.12.1

* github.com/mgechev/revive v1.0.3 -> v1.0.6

* github.com/microcosm-cc/bluemonday v1.0.7 -> v1.0.8

* github.com/niklasfasching/go-org v1.4.0 -> v1.5.0

* github.com/olivere/elastic v7.0.22 -> v7.0.24

* github.com/pelletier/go-toml v1.8.1 -> v1.9.0

* github.com/prometheus/client_golang v1.9.0 -> v1.10.0

* github.com/xanzy/go-gitlab v0.44.0 -> v0.48.0

* github.com/yuin/goldmark v1.3.3 -> v1.3.5

* github.com/6543/go-version v1.2.4 -> v1.3.1

* do github.com/lib/pq v1.10.0 -> v1.10.1 again ...
2021-04-22 20:08:53 -04:00

69 lines
1.6 KiB
Go
Vendored

// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package detrand provides deterministically random functionality.
//
// The pseudo-randomness of these functions is seeded by the program binary
// itself and guarantees that the output does not change within a program,
// while ensuring that the output is unstable across different builds.
package detrand
import (
"encoding/binary"
"hash/fnv"
"os"
)
// Disable disables detrand such that all functions returns the zero value.
// This function is not concurrent-safe and must be called during program init.
func Disable() {
randSeed = 0
}
// Bool returns a deterministically random boolean.
func Bool() bool {
return randSeed%2 == 1
}
// Intn returns a deterministically random integer between 0 and n-1, inclusive.
func Intn(n int) int {
if n <= 0 {
panic("must be positive")
}
return int(randSeed % uint64(n))
}
// randSeed is a best-effort at an approximate hash of the Go binary.
var randSeed = binaryHash()
func binaryHash() uint64 {
// Open the Go binary.
s, err := os.Executable()
if err != nil {
return 0
}
f, err := os.Open(s)
if err != nil {
return 0
}
defer f.Close()
// Hash the size and several samples of the Go binary.
const numSamples = 8
var buf [64]byte
h := fnv.New64()
fi, err := f.Stat()
if err != nil {
return 0
}
binary.LittleEndian.PutUint64(buf[:8], uint64(fi.Size()))
h.Write(buf[:8])
for i := int64(0); i < numSamples; i++ {
if _, err := f.ReadAt(buf[:], i*fi.Size()/numSamples); err != nil {
return 0
}
h.Write(buf[:])
}
return h.Sum64()
}