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-rw-r--r--dependencies/pkg/mod/github.com/google/uuid@v1.6.0/version7.go104
1 files changed, 104 insertions, 0 deletions
diff --git a/dependencies/pkg/mod/github.com/google/uuid@v1.6.0/version7.go b/dependencies/pkg/mod/github.com/google/uuid@v1.6.0/version7.go
new file mode 100644
index 0000000..3167b64
--- /dev/null
+++ b/dependencies/pkg/mod/github.com/google/uuid@v1.6.0/version7.go
@@ -0,0 +1,104 @@
+// 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
+}