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Diffstat (limited to 'vendor/github.com/docker/distribution/uuid/uuid.go')
-rw-r--r--vendor/github.com/docker/distribution/uuid/uuid.go126
1 files changed, 0 insertions, 126 deletions
diff --git a/vendor/github.com/docker/distribution/uuid/uuid.go b/vendor/github.com/docker/distribution/uuid/uuid.go
deleted file mode 100644
index d433ccaf5..000000000
--- a/vendor/github.com/docker/distribution/uuid/uuid.go
+++ /dev/null
@@ -1,126 +0,0 @@
-// Package uuid provides simple UUID generation. Only version 4 style UUIDs
-// can be generated.
-//
-// Please see http://tools.ietf.org/html/rfc4122 for details on UUIDs.
-package uuid
-
-import (
- "crypto/rand"
- "fmt"
- "io"
- "os"
- "syscall"
- "time"
-)
-
-const (
- // Bits is the number of bits in a UUID
- Bits = 128
-
- // Size is the number of bytes in a UUID
- Size = Bits / 8
-
- format = "%08x-%04x-%04x-%04x-%012x"
-)
-
-var (
- // ErrUUIDInvalid indicates a parsed string is not a valid uuid.
- ErrUUIDInvalid = fmt.Errorf("invalid uuid")
-
- // Loggerf can be used to override the default logging destination. Such
- // log messages in this library should be logged at warning or higher.
- Loggerf = func(format string, args ...interface{}) {}
-)
-
-// UUID represents a UUID value. UUIDs can be compared and set to other values
-// and accessed by byte.
-type UUID [Size]byte
-
-// Generate creates a new, version 4 uuid.
-func Generate() (u UUID) {
- const (
- // ensures we backoff for less than 450ms total. Use the following to
- // select new value, in units of 10ms:
- // n*(n+1)/2 = d -> n^2 + n - 2d -> n = (sqrt(8d + 1) - 1)/2
- maxretries = 9
- backoff = time.Millisecond * 10
- )
-
- var (
- totalBackoff time.Duration
- count int
- retries int
- )
-
- for {
- // This should never block but the read may fail. Because of this,
- // we just try to read the random number generator until we get
- // something. This is a very rare condition but may happen.
- b := time.Duration(retries) * backoff
- time.Sleep(b)
- totalBackoff += b
-
- n, err := io.ReadFull(rand.Reader, u[count:])
- if err != nil {
- if retryOnError(err) && retries < maxretries {
- count += n
- retries++
- Loggerf("error generating version 4 uuid, retrying: %v", err)
- continue
- }
-
- // Any other errors represent a system problem. What did someone
- // do to /dev/urandom?
- panic(fmt.Errorf("error reading random number generator, retried for %v: %v", totalBackoff.String(), err))
- }
-
- break
- }
-
- u[6] = (u[6] & 0x0f) | 0x40 // set version byte
- u[8] = (u[8] & 0x3f) | 0x80 // set high order byte 0b10{8,9,a,b}
-
- return u
-}
-
-// Parse attempts to extract a uuid from the string or returns an error.
-func Parse(s string) (u UUID, err error) {
- if len(s) != 36 {
- return UUID{}, ErrUUIDInvalid
- }
-
- // create stack addresses for each section of the uuid.
- p := make([][]byte, 5)
-
- if _, err := fmt.Sscanf(s, format, &p[0], &p[1], &p[2], &p[3], &p[4]); err != nil {
- return u, err
- }
-
- copy(u[0:4], p[0])
- copy(u[4:6], p[1])
- copy(u[6:8], p[2])
- copy(u[8:10], p[3])
- copy(u[10:16], p[4])
-
- return
-}
-
-func (u UUID) String() string {
- return fmt.Sprintf(format, u[:4], u[4:6], u[6:8], u[8:10], u[10:])
-}
-
-// retryOnError tries to detect whether or not retrying would be fruitful.
-func retryOnError(err error) bool {
- switch err := err.(type) {
- case *os.PathError:
- return retryOnError(err.Err) // unpack the target error
- case syscall.Errno:
- if err == syscall.EPERM {
- // EPERM represents an entropy pool exhaustion, a condition under
- // which we backoff and retry.
- return true
- }
- }
-
- return false
-}