-
Notifications
You must be signed in to change notification settings - Fork 566
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
- Loading branch information
Showing
6 changed files
with
116 additions
and
9 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,105 @@ | ||
| package uuid | ||
|
|
||
| import ( | ||
| "crypto/md5" | ||
| "crypto/rand" | ||
| "crypto/sha1" | ||
| "encoding/hex" | ||
| "hash" | ||
| "io" | ||
| ) | ||
|
|
||
| // Nil empty UUID, all zeros | ||
| var Nil UUID | ||
|
|
||
| // A UUID is a 128 bit (16 byte) Universal Unique IDentifier as defined in RFC | ||
| // 4122. | ||
| type UUID [16]byte | ||
|
|
||
| // Bytes returns bytes slice representation of UUID. | ||
| func (uuid UUID) Bytes() []byte { | ||
| return uuid[:] | ||
| } | ||
|
|
||
| // String returns the string form of uuid, xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx | ||
| // , or "" if uuid is invalid. | ||
| func (uuid UUID) String() string { | ||
| var buf [36]byte | ||
| encodeHex(buf[:], uuid) | ||
| return string(buf[:]) | ||
| } | ||
|
|
||
| func encodeHex(dst []byte, uuid UUID) { | ||
| hex.Encode(dst, uuid[:4]) | ||
| dst[8] = '-' | ||
| hex.Encode(dst[9:13], uuid[4:6]) | ||
| dst[13] = '-' | ||
| hex.Encode(dst[14:18], uuid[6:8]) | ||
| dst[18] = '-' | ||
| hex.Encode(dst[19:23], uuid[8:10]) | ||
| dst[23] = '-' | ||
| hex.Encode(dst[24:], uuid[10:]) | ||
| } | ||
|
|
||
| // Must returns uuid if err is nil and panics otherwise. | ||
| func Must(uuid UUID, err error) UUID { | ||
| if err != nil { | ||
| panic(err) | ||
| } | ||
| return uuid | ||
| } | ||
|
|
||
| // NewRandom returns a Random (Version 4) UUID. | ||
| // | ||
| // The strength of the UUIDs is based on the strength of the crypto/rand | ||
| // package. | ||
| // | ||
| // 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) { | ||
| var uuid UUID | ||
| _, err := io.ReadFull(rand.Reader, 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 | ||
| } | ||
|
|
||
| // NewHash returns a new UUID derived from the hash of space concatenated with | ||
| // data generated by h. The hash should be at least 16 byte in length. The | ||
| // first 16 bytes of the hash are used to form the UUID. The version of the | ||
| // UUID will be the lower 4 bits of version. | ||
| func NewHash(h hash.Hash, space UUID, data []byte, version int) UUID { | ||
| h.Reset() | ||
| h.Write(space[:]) | ||
| h.Write(data) | ||
| s := h.Sum(nil) | ||
| var uuid UUID | ||
| copy(uuid[:], s) | ||
| uuid[6] = (uuid[6] & 0x0f) | uint8((version&0xf)<<4) | ||
| uuid[8] = (uuid[8] & 0x3f) | 0x80 // RFC 4122 variant | ||
| return uuid | ||
| } | ||
|
|
||
| // NewMD5 returns a new MD5 (Version 3) UUID based on the | ||
| // supplied name space and data. It is the same as calling: | ||
| // | ||
| // NewHash(md5.New(), space, data, 3) | ||
| func NewMD5(space UUID, data []byte) UUID { | ||
| return NewHash(md5.New(), space, data, 3) | ||
| } | ||
|
|
||
| // NewSHA1 returns a new SHA1 (Version 5) UUID based on the | ||
| // supplied name space and data. It is the same as calling: | ||
| // | ||
| // NewHash(sha1.New(), space, data, 5) | ||
| func NewSHA1(space UUID, data []byte) UUID { | ||
| return NewHash(sha1.New(), space, data, 5) | ||
| } |