Add vendor github.com/rs/xid

7 files changed, 456 insertions, 0 deletions

diff --git a/vendor/github.com/rs/xid/LICENSE b/vendor/github.com/rs/xid/LICENSE
new file mode 100644
index 00000000..47c5e9d2
--- /dev/null
+++ b/vendor/github.com/rs/xid/LICENSE
@@ -0,0 +1,19 @@
+Copyright (c) 2015 Olivier Poitrey <rs@dailymotion.com>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is furnished
+to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/vendor/github.com/rs/xid/hostid_darwin.go b/vendor/github.com/rs/xid/hostid_darwin.go
new file mode 100644
index 00000000..abd06840
--- /dev/null
+++ b/vendor/github.com/rs/xid/hostid_darwin.go
@@ -0,0 +1,9 @@
+// +build darwin
+
+package xid
+
+import "golang.org/x/sys/unix"
+
+func readPlatformMachineID() (string, error) {
+	return unix.Sysctl("kern.uuid")
+}
diff --git a/vendor/github.com/rs/xid/hostid_fallback.go b/vendor/github.com/rs/xid/hostid_fallback.go
new file mode 100644
index 00000000..7fbd3c00
--- /dev/null
+++ b/vendor/github.com/rs/xid/hostid_fallback.go
@@ -0,0 +1,9 @@
+// +build !darwin,!linux,!freebsd,!windows
+
+package xid
+
+import "errors"
+
+func readPlatformMachineID() (string, error) {
+	return "", errors.New("not implemented")
+}
diff --git a/vendor/github.com/rs/xid/hostid_freebsd.go b/vendor/github.com/rs/xid/hostid_freebsd.go
new file mode 100644
index 00000000..df2bd13c
--- /dev/null
+++ b/vendor/github.com/rs/xid/hostid_freebsd.go
@@ -0,0 +1,9 @@
+// +build freebsd
+
+package xid
+
+import "golang.org/x/sys/unix"
+
+func readPlatformMachineID() (string, error) {
+	return unix.Sysctl("kern.hostuuid")
+}
diff --git a/vendor/github.com/rs/xid/hostid_linux.go b/vendor/github.com/rs/xid/hostid_linux.go
new file mode 100644
index 00000000..7d0c4a9e
--- /dev/null
+++ b/vendor/github.com/rs/xid/hostid_linux.go
@@ -0,0 +1,10 @@
+// +build linux
+
+package xid
+
+import "io/ioutil"
+
+func readPlatformMachineID() (string, error) {
+	b, err := ioutil.ReadFile("/sys/class/dmi/id/product_uuid")
+	return string(b), err
+}
diff --git a/vendor/github.com/rs/xid/hostid_windows.go b/vendor/github.com/rs/xid/hostid_windows.go
new file mode 100644
index 00000000..b8e1c2cb
--- /dev/null
+++ b/vendor/github.com/rs/xid/hostid_windows.go
@@ -0,0 +1,39 @@
+// +build windows
+
+package xid
+
+import (
+	"fmt"
+	"unsafe"
+
+	"golang.org/x/sys/windows"
+)
+
+func readPlatformMachineID() (string, error) {
+	// source: https://github.com/shirou/gopsutil/blob/master/host/host_windows.go
+	var h windows.Handle
+	err := windows.RegOpenKeyEx(windows.HKEY_LOCAL_MACHINE, windows.StringToUTF16Ptr(`SOFTWARE\Microsoft\Cryptography`), 0, windows.KEY_READ|windows.KEY_WOW64_64KEY, &h)
+	if err != nil {
+		return "", err
+	}
+	defer windows.RegCloseKey(h)
+
+	const windowsRegBufLen = 74 // len(`{`) + len(`abcdefgh-1234-456789012-123345456671` * 2) + len(`}`) // 2 == bytes/UTF16
+	const uuidLen = 36
+
+	var regBuf [windowsRegBufLen]uint16
+	bufLen := uint32(windowsRegBufLen)
+	var valType uint32
+	err = windows.RegQueryValueEx(h, windows.StringToUTF16Ptr(`MachineGuid`), nil, &valType, (*byte)(unsafe.Pointer(&regBuf[0])), &bufLen)
+	if err != nil {
+		return "", err
+	}
+
+	hostID := windows.UTF16ToString(regBuf[:])
+	hostIDLen := len(hostID)
+	if hostIDLen != uuidLen {
+		return "", fmt.Errorf("HostID incorrect: %q\n", hostID)
+	}
+
+	return hostID, nil
+}
diff --git a/vendor/github.com/rs/xid/id.go b/vendor/github.com/rs/xid/id.go
new file mode 100644
index 00000000..51b8d7fa
--- /dev/null
+++ b/vendor/github.com/rs/xid/id.go
@@ -0,0 +1,361 @@
+// Package xid is a globally unique id generator suited for web scale
+//
+// Xid is using Mongo Object ID algorithm to generate globally unique ids:
+// https://docs.mongodb.org/manual/reference/object-id/
+//
+//   - 4-byte value representing the seconds since the Unix epoch,
+//   - 3-byte machine identifier,
+//   - 2-byte process id, and
+//   - 3-byte counter, starting with a random value.
+//
+// The binary representation of the id is compatible with Mongo 12 bytes Object IDs.
+// The string representation is using base32 hex (w/o padding) for better space efficiency
+// when stored in that form (20 bytes). The hex variant of base32 is used to retain the
+// sortable property of the id.
+//
+// Xid doesn't use base64 because case sensitivity and the 2 non alphanum chars may be an
+// issue when transported as a string between various systems. Base36 wasn't retained either
+// because 1/ it's not standard 2/ the resulting size is not predictable (not bit aligned)
+// and 3/ it would not remain sortable. To validate a base32 `xid`, expect a 20 chars long,
+// all lowercase sequence of `a` to `v` letters and `0` to `9` numbers (`[0-9a-v]{20}`).
+//
+// UUID is 16 bytes (128 bits), snowflake is 8 bytes (64 bits), xid stands in between
+// with 12 bytes with a more compact string representation ready for the web and no
+// required configuration or central generation server.
+//
+// Features:
+//
+//   - Size: 12 bytes (96 bits), smaller than UUID, larger than snowflake
+//   - Base32 hex encoded by default (16 bytes storage when transported as printable string)
+//   - Non configured, you don't need set a unique machine and/or data center id
+//   - K-ordered
+//   - Embedded time with 1 second precision
+//   - Unicity guaranteed for 16,777,216 (24 bits) unique ids per second and per host/process
+//
+// Best used with xlog's RequestIDHandler (https://godoc.org/github.com/rs/xlog#RequestIDHandler).
+//
+// References:
+//
+//   - http://www.slideshare.net/davegardnerisme/unique-id-generation-in-distributed-systems
+//   - https://en.wikipedia.org/wiki/Universally_unique_identifier
+//   - https://blog.twitter.com/2010/announcing-snowflake
+package xid
+
+import (
+	"crypto/md5"
+	"crypto/rand"
+	"database/sql/driver"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"hash/crc32"
+	"io/ioutil"
+	"os"
+	"sync/atomic"
+	"time"
+	"bytes"
+	"sort"
+)
+
+// Code inspired from mgo/bson ObjectId
+
+// ID represents a unique request id
+type ID [rawLen]byte
+
+const (
+	encodedLen = 20 // string encoded len
+	rawLen     = 12 // binary raw len
+
+	// encoding stores a custom version of the base32 encoding with lower case
+	// letters.
+	encoding = "0123456789abcdefghijklmnopqrstuv"
+)
+
+var (
+	// ErrInvalidID is returned when trying to unmarshal an invalid ID
+	ErrInvalidID = errors.New("xid: invalid ID")
+
+	// objectIDCounter is atomically incremented when generating a new ObjectId
+	// using NewObjectId() function. It's used as a counter part of an id.
+	// This id is initialized with a random value.
+	objectIDCounter = randInt()
+
+	// machineId stores machine id generated once and used in subsequent calls
+	// to NewObjectId function.
+	machineID = readMachineID()
+
+	// pid stores the current process id
+	pid = os.Getpid()
+
+	nilID ID
+
+	// dec is the decoding map for base32 encoding
+	dec [256]byte
+)
+
+func init() {
+	for i := 0; i < len(dec); i++ {
+		dec[i] = 0xFF
+	}
+	for i := 0; i < len(encoding); i++ {
+		dec[encoding[i]] = byte(i)
+	}
+
+	// If /proc/self/cpuset exists and is not /, we can assume that we are in a
+	// form of container and use the content of cpuset xor-ed with the PID in
+	// order get a reasonable machine global unique PID.
+	b, err := ioutil.ReadFile("/proc/self/cpuset")
+	if err == nil && len(b) > 1 {
+		pid ^= int(crc32.ChecksumIEEE(b))
+	}
+}
+
+// readMachineId generates machine id and puts it into the machineId global
+// variable. If this function fails to get the hostname, it will cause
+// a runtime error.
+func readMachineID() []byte {
+	id := make([]byte, 3)
+	hid, err := readPlatformMachineID()
+	if err != nil || len(hid) == 0 {
+		hid, err = os.Hostname()
+	}
+	if err == nil && len(hid) != 0 {
+		hw := md5.New()
+		hw.Write([]byte(hid))
+		copy(id, hw.Sum(nil))
+	} else {
+		// Fallback to rand number if machine id can't be gathered
+		if _, randErr := rand.Reader.Read(id); randErr != nil {
+			panic(fmt.Errorf("xid: cannot get hostname nor generate a random number: %v; %v", err, randErr))
+		}
+	}
+	return id
+}
+
+// randInt generates a random uint32
+func randInt() uint32 {
+	b := make([]byte, 3)
+	if _, err := rand.Reader.Read(b); err != nil {
+		panic(fmt.Errorf("xid: cannot generate random number: %v;", err))
+	}
+	return uint32(b[0])<<16 | uint32(b[1])<<8 | uint32(b[2])
+}
+
+// New generates a globally unique ID
+func New() ID {
+	var id ID
+	// Timestamp, 4 bytes, big endian
+	binary.BigEndian.PutUint32(id[:], uint32(time.Now().Unix()))
+	// Machine, first 3 bytes of md5(hostname)
+	id[4] = machineID[0]
+	id[5] = machineID[1]
+	id[6] = machineID[2]
+	// Pid, 2 bytes, specs don't specify endianness, but we use big endian.
+	id[7] = byte(pid >> 8)
+	id[8] = byte(pid)
+	// Increment, 3 bytes, big endian
+	i := atomic.AddUint32(&objectIDCounter, 1)
+	id[9] = byte(i >> 16)
+	id[10] = byte(i >> 8)
+	id[11] = byte(i)
+	return id
+}
+
+// FromString reads an ID from its string representation
+func FromString(id string) (ID, error) {
+	i := &ID{}
+	err := i.UnmarshalText([]byte(id))
+	return *i, err
+}
+
+// String returns a base32 hex lowercased with no padding representation of the id (char set is 0-9, a-v).
+func (id ID) String() string {
+	text := make([]byte, encodedLen)
+	encode(text, id[:])
+	return string(text)
+}
+
+// MarshalText implements encoding/text TextMarshaler interface
+func (id ID) MarshalText() ([]byte, error) {
+	text := make([]byte, encodedLen)
+	encode(text, id[:])
+	return text, nil
+}
+
+// MarshalJSON implements encoding/json Marshaler interface
+func (id ID) MarshalJSON() ([]byte, error) {
+	if id.IsNil() {
+		return []byte("null"), nil
+	}
+	text, err := id.MarshalText()
+	return []byte(`"` + string(text) + `"`), err
+}
+
+// encode by unrolling the stdlib base32 algorithm + removing all safe checks
+func encode(dst, id []byte) {
+	dst[0] = encoding[id[0]>>3]
+	dst[1] = encoding[(id[1]>>6)&0x1F|(id[0]<<2)&0x1F]
+	dst[2] = encoding[(id[1]>>1)&0x1F]
+	dst[3] = encoding[(id[2]>>4)&0x1F|(id[1]<<4)&0x1F]
+	dst[4] = encoding[id[3]>>7|(id[2]<<1)&0x1F]
+	dst[5] = encoding[(id[3]>>2)&0x1F]
+	dst[6] = encoding[id[4]>>5|(id[3]<<3)&0x1F]
+	dst[7] = encoding[id[4]&0x1F]
+	dst[8] = encoding[id[5]>>3]
+	dst[9] = encoding[(id[6]>>6)&0x1F|(id[5]<<2)&0x1F]
+	dst[10] = encoding[(id[6]>>1)&0x1F]
+	dst[11] = encoding[(id[7]>>4)&0x1F|(id[6]<<4)&0x1F]
+	dst[12] = encoding[id[8]>>7|(id[7]<<1)&0x1F]
+	dst[13] = encoding[(id[8]>>2)&0x1F]
+	dst[14] = encoding[(id[9]>>5)|(id[8]<<3)&0x1F]
+	dst[15] = encoding[id[9]&0x1F]
+	dst[16] = encoding[id[10]>>3]
+	dst[17] = encoding[(id[11]>>6)&0x1F|(id[10]<<2)&0x1F]
+	dst[18] = encoding[(id[11]>>1)&0x1F]
+	dst[19] = encoding[(id[11]<<4)&0x1F]
+}
+
+// UnmarshalText implements encoding/text TextUnmarshaler interface
+func (id *ID) UnmarshalText(text []byte) error {
+	if len(text) != encodedLen {
+		return ErrInvalidID
+	}
+	for _, c := range text {
+		if dec[c] == 0xFF {
+			return ErrInvalidID
+		}
+	}
+	decode(id, text)
+	return nil
+}
+
+// UnmarshalJSON implements encoding/json Unmarshaler interface
+func (id *ID) UnmarshalJSON(b []byte) error {
+	s := string(b)
+	if s == "null" {
+		*id = nilID
+		return nil
+	}
+	return id.UnmarshalText(b[1 : len(b)-1])
+}
+
+// decode by unrolling the stdlib base32 algorithm + removing all safe checks
+func decode(id *ID, src []byte) {
+	id[0] = dec[src[0]]<<3 | dec[src[1]]>>2
+	id[1] = dec[src[1]]<<6 | dec[src[2]]<<1 | dec[src[3]]>>4
+	id[2] = dec[src[3]]<<4 | dec[src[4]]>>1
+	id[3] = dec[src[4]]<<7 | dec[src[5]]<<2 | dec[src[6]]>>3
+	id[4] = dec[src[6]]<<5 | dec[src[7]]
+	id[5] = dec[src[8]]<<3 | dec[src[9]]>>2
+	id[6] = dec[src[9]]<<6 | dec[src[10]]<<1 | dec[src[11]]>>4
+	id[7] = dec[src[11]]<<4 | dec[src[12]]>>1
+	id[8] = dec[src[12]]<<7 | dec[src[13]]<<2 | dec[src[14]]>>3
+	id[9] = dec[src[14]]<<5 | dec[src[15]]
+	id[10] = dec[src[16]]<<3 | dec[src[17]]>>2
+	id[11] = dec[src[17]]<<6 | dec[src[18]]<<1 | dec[src[19]]>>4
+}
+
+// Time returns the timestamp part of the id.
+// It's a runtime error to call this method with an invalid id.
+func (id ID) Time() time.Time {
+	// First 4 bytes of ObjectId is 32-bit big-endian seconds from epoch.
+	secs := int64(binary.BigEndian.Uint32(id[0:4]))
+	return time.Unix(secs, 0)
+}
+
+// Machine returns the 3-byte machine id part of the id.
+// It's a runtime error to call this method with an invalid id.
+func (id ID) Machine() []byte {
+	return id[4:7]
+}
+
+// Pid returns the process id part of the id.
+// It's a runtime error to call this method with an invalid id.
+func (id ID) Pid() uint16 {
+	return binary.BigEndian.Uint16(id[7:9])
+}
+
+// Counter returns the incrementing value part of the id.
+// It's a runtime error to call this method with an invalid id.
+func (id ID) Counter() int32 {
+	b := id[9:12]
+	// Counter is stored as big-endian 3-byte value
+	return int32(uint32(b[0])<<16 | uint32(b[1])<<8 | uint32(b[2]))
+}
+
+// Value implements the driver.Valuer interface.
+func (id ID) Value() (driver.Value, error) {
+	if id.IsNil() {
+		return nil, nil
+	}
+	b, err := id.MarshalText()
+	return string(b), err
+}
+
+// Scan implements the sql.Scanner interface.
+func (id *ID) Scan(value interface{}) (err error) {
+	switch val := value.(type) {
+	case string:
+		return id.UnmarshalText([]byte(val))
+	case []byte:
+		return id.UnmarshalText(val)
+	case nil:
+		*id = nilID
+		return nil
+	default:
+		return fmt.Errorf("xid: scanning unsupported type: %T", value)
+	}
+}
+
+// IsNil Returns true if this is a "nil" ID
+func (id ID) IsNil() bool {
+	return id == nilID
+}
+
+// NilID returns a zero value for `xid.ID`.
+func NilID() ID {
+	return nilID
+}
+
+// Bytes returns the byte array representation of `ID`
+func (id ID) Bytes() []byte {
+	return id[:]
+}
+
+// FromBytes convert the byte array representation of `ID` back to `ID`
+func FromBytes(b []byte) (ID, error) {
+	var id ID
+	if len(b) != rawLen {
+		return id, ErrInvalidID
+	}
+	copy(id[:], b)
+	return id, nil
+}
+
+// Compare returns an integer comparing two IDs. It behaves just like `bytes.Compare`.
+// The result will be 0 if two IDs are identical, -1 if current id is less than the other one,
+// and 1 if current id is greater than the other.
+func (id ID) Compare(other ID) int {
+	return bytes.Compare(id[:], other[:])
+}
+
+
+type sorter []ID
+
+func (s sorter) Len() int {
+	return len(s)
+}
+
+func (s sorter) Less(i, j int) bool {
+	return s[i].Compare(s[j]) < 0
+}
+
+func (s sorter) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+// Sort sorts an array of IDs inplace.
+// It works by wrapping `[]ID` and use `sort.Sort`.
+func Sort(ids []ID) {
+	sort.Sort(sorter(ids))
+}