diff options
Diffstat (limited to '')
-rw-r--r-- | dependencies/pkg/mod/github.com/google/uuid@v1.3.0/version4.go | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/dependencies/pkg/mod/github.com/google/uuid@v1.3.0/version4.go b/dependencies/pkg/mod/github.com/google/uuid@v1.3.0/version4.go new file mode 100644 index 0000000..7697802 --- /dev/null +++ b/dependencies/pkg/mod/github.com/google/uuid@v1.3.0/version4.go @@ -0,0 +1,76 @@ +// Copyright 2016 Google Inc. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package uuid + +import "io" + +// New creates a new random UUID or panics. New is equivalent to +// the expression +// +// uuid.Must(uuid.NewRandom()) +func New() UUID { + return Must(NewRandom()) +} + +// NewString creates a new random UUID and returns it as a string or panics. +// NewString is equivalent to the expression +// +// uuid.New().String() +func NewString() string { + return Must(NewRandom()).String() +} + +// NewRandom returns a Random (Version 4) UUID. +// +// The strength of the UUIDs is based on the strength of the crypto/rand +// package. +// +// Uses the randomness pool if it was enabled with EnableRandPool. +// +// A note about uniqueness derived from the UUID Wikipedia entry: +// +// Randomly generated UUIDs have 122 random bits. One's annual risk of being +// hit by a meteorite is estimated to be one chance in 17 billion, that +// means the probability is about 0.00000000006 (6 × 10−11), +// equivalent to the odds of creating a few tens of trillions of UUIDs in a +// year and having one duplicate. +func NewRandom() (UUID, error) { + if !poolEnabled { + return NewRandomFromReader(rander) + } + return newRandomFromPool() +} + +// NewRandomFromReader returns a UUID based on bytes read from a given io.Reader. +func NewRandomFromReader(r io.Reader) (UUID, error) { + var uuid UUID + _, err := io.ReadFull(r, uuid[:]) + if err != nil { + return Nil, err + } + uuid[6] = (uuid[6] & 0x0f) | 0x40 // Version 4 + uuid[8] = (uuid[8] & 0x3f) | 0x80 // Variant is 10 + return uuid, nil +} + +func newRandomFromPool() (UUID, error) { + var uuid UUID + poolMu.Lock() + if poolPos == randPoolSize { + _, err := io.ReadFull(rander, pool[:]) + if err != nil { + poolMu.Unlock() + return Nil, err + } + poolPos = 0 + } + copy(uuid[:], pool[poolPos:(poolPos+16)]) + poolPos += 16 + poolMu.Unlock() + + uuid[6] = (uuid[6] & 0x0f) | 0x40 // Version 4 + uuid[8] = (uuid[8] & 0x3f) | 0x80 // Variant is 10 + return uuid, nil +} |