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Diffstat (limited to 'vendor/github.com/google/uuid/version7.go')
-rw-r--r-- | vendor/github.com/google/uuid/version7.go | 104 |
1 files changed, 0 insertions, 104 deletions
diff --git a/vendor/github.com/google/uuid/version7.go b/vendor/github.com/google/uuid/version7.go deleted file mode 100644 index 3167b643d..000000000 --- a/vendor/github.com/google/uuid/version7.go +++ /dev/null @@ -1,104 +0,0 @@ -// Copyright 2023 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" -) - -// UUID version 7 features a time-ordered value field derived from the widely -// implemented and well known Unix Epoch timestamp source, -// the number of milliseconds seconds since midnight 1 Jan 1970 UTC, leap seconds excluded. -// As well as improved entropy characteristics over versions 1 or 6. -// -// see https://datatracker.ietf.org/doc/html/draft-peabody-dispatch-new-uuid-format-03#name-uuid-version-7 -// -// Implementations SHOULD utilize UUID version 7 over UUID version 1 and 6 if possible. -// -// NewV7 returns a Version 7 UUID based on the current time(Unix Epoch). -// Uses the randomness pool if it was enabled with EnableRandPool. -// On error, NewV7 returns Nil and an error -func NewV7() (UUID, error) { - uuid, err := NewRandom() - if err != nil { - return uuid, err - } - makeV7(uuid[:]) - return uuid, nil -} - -// NewV7FromReader returns a Version 7 UUID based on the current time(Unix Epoch). -// it use NewRandomFromReader fill random bits. -// On error, NewV7FromReader returns Nil and an error. -func NewV7FromReader(r io.Reader) (UUID, error) { - uuid, err := NewRandomFromReader(r) - if err != nil { - return uuid, err - } - - makeV7(uuid[:]) - return uuid, nil -} - -// makeV7 fill 48 bits time (uuid[0] - uuid[5]), set version b0111 (uuid[6]) -// uuid[8] already has the right version number (Variant is 10) -// see function NewV7 and NewV7FromReader -func makeV7(uuid []byte) { - /* - 0 1 2 3 - 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | unix_ts_ms | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | unix_ts_ms | ver | rand_a (12 bit seq) | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - |var| rand_b | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | rand_b | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - */ - _ = uuid[15] // bounds check - - t, s := getV7Time() - - uuid[0] = byte(t >> 40) - uuid[1] = byte(t >> 32) - uuid[2] = byte(t >> 24) - uuid[3] = byte(t >> 16) - uuid[4] = byte(t >> 8) - uuid[5] = byte(t) - - uuid[6] = 0x70 | (0x0F & byte(s>>8)) - uuid[7] = byte(s) -} - -// lastV7time is the last time we returned stored as: -// -// 52 bits of time in milliseconds since epoch -// 12 bits of (fractional nanoseconds) >> 8 -var lastV7time int64 - -const nanoPerMilli = 1000000 - -// getV7Time returns the time in milliseconds and nanoseconds / 256. -// The returned (milli << 12 + seq) is guarenteed to be greater than -// (milli << 12 + seq) returned by any previous call to getV7Time. -func getV7Time() (milli, seq int64) { - timeMu.Lock() - defer timeMu.Unlock() - - nano := timeNow().UnixNano() - milli = nano / nanoPerMilli - // Sequence number is between 0 and 3906 (nanoPerMilli>>8) - seq = (nano - milli*nanoPerMilli) >> 8 - now := milli<<12 + seq - if now <= lastV7time { - now = lastV7time + 1 - milli = now >> 12 - seq = now & 0xfff - } - lastV7time = now - return milli, seq -} |