Documentation improvements.

Also, I renamed a couple of the sd_id128 functions for better clarity.  But
since I haven't pushed since originally implementing them, I'm not labeling
it as a breaking change.

1 files changed, 0 insertions, 222 deletions

diff --git a/sd_id128/sd_id128.go b/sd_id128/sd_id128.go
deleted file mode 100644
index 063a4d4..0000000
--- a/sd_id128/sd_id128.go
+++ /dev/null
@@ -1,222 +0,0 @@
-// Copyright 2016 Luke Shumaker
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Package sd_id128 provides functions for dealing with 128-bit IDs.
-package sd_id128
-
-import (
-	"crypto/rand"
-	"errors"
-	"os"
-	"strings"
-)
-
-var (
-	ErrInvalid = errors.New("Invalid ID")
-	ErrNone    = errors.New("No Invocation ID set")
-)
-
-type ID128 [16]byte
-
-// String formats the ID as a hexadecimal number.
-func (id ID128) String() string {
-	var s [32]byte
-	for n := range id {
-		s[n*2] = hexchar(id[n] >> 4)
-		s[n*2+1] = hexchar(id[n] & 0xF)
-	}
-	return string(s[:])
-}
-
-// UUID formats the ID as a UUID string.
-func (id ID128) UUID() string {
-	var s [36]byte
-	k := 0
-	for n := range id {
-		switch n {
-		case 4, 6, 8, 10:
-			s[k] = '-'
-			k++
-		}
-		s[k] = hexchar(id[n] >> 4)
-		k++
-		s[k] = hexchar(id[n] & 0xF)
-		k++
-	}
-	return string(s[:])
-}
-
-// Parse parses a 128-bit ID represented either as a hexadecimal
-// number, or as a UUID string (that is, a hexadecimal number with
-// hyphens inserted at positions 8, 12, 18, and 23).
-func Parse(s string) (ID128, error) {
-	ret := ID128{}
-	isGuid := false
-
-	i := 0
-	n := 0
-	for n < 16 {
-		if s[i] == '-' {
-			if i == 8 {
-				isGuid = true
-			} else if i == 13 || i == 18 || i == 23 {
-				if !isGuid {
-					return ID128{}, ErrInvalid
-				}
-			} else {
-				return ID128{}, ErrInvalid
-			}
-			i++
-		} else {
-			if i+2 >= len(s) {
-				return ID128{}, ErrInvalid
-			}
-
-			a, err := unhexchar(s[i])
-			i++
-			if err != nil {
-				return ID128{}, err
-			}
-
-			b, err := unhexchar(s[i])
-			i++
-			if err != nil {
-				return ID128{}, err
-			}
-
-			ret[n] = (a << 4) | b
-			n++
-		}
-	}
-
-	if !((i == 36 && isGuid) || (i == 32 && !isGuid)) {
-		return ID128{}, ErrInvalid
-	}
-	if i != len(s) {
-		return ID128{}, ErrInvalid
-	}
-
-	return ret, nil
-}
-
-// ParsePlain is like Parse, but only accepts hexadecimal numbers, not
-// UUID-formatted strings.
-func ParsePlain(s string) (ID128, error) {
-	if len(s) != 32 {
-		return ID128{}, ErrInvalid
-	}
-	return Parse(s)
-}
-
-// ParseUUID is like Parse, but only accepts UUID-formatted strings,
-// not hexadecimal numbers.
-func ParseUUID(s string) (ID128, error) {
-	if len(s) != 36 {
-		return ID128{}, ErrInvalid
-	}
-	return Parse(s)
-}
-
-// GetRandomID generates a random v4 UUID (122 random bits).
-func GetRandomID() (ID128, error) {
-	var id ID128
-	_, err := rand.Read(id[:])
-	if err != nil {
-		return ID128{}, err
-	}
-
-	// Turn this in to a valid v4 UUID, to be nice.
-
-	// Set UUID version to 4 --- truly random generation
-	id[6] = (id[6] & 0x0F) | 0x40
-
-	// Set the UUID variant to DCE
-	id[8] = (id[8] & 0x3F) | 0x80
-
-	return id, nil
-}
-
-var cachedMachineID ID128
-
-// GetMachineID returns a unique identifier for this machine.
-//
-// This is read as a plain hexadecimal number (with an optional
-// trailing newline) from "/etc/machine-id".
-func GetMachineID() (ID128, error) {
-	if cachedMachineID == (ID128{}) {
-		str, err := readfile("/etc/machine-id")
-		if err != nil {
-			return ID128{}, err
-		}
-		id, err := ParsePlain(strings.TrimSuffix(str, "\n"))
-		if err != nil {
-			return ID128{}, err
-		}
-		if id == (ID128{}) {
-			return ID128{}, ErrInvalid
-		}
-		cachedMachineID = id
-	}
-	return cachedMachineID, nil
-}
-
-var cachedBootID ID128
-
-// GetBootID returns a unique identifier for this boot.
-//
-// This is read as a UUID (with trailing newline) from
-// "/proc/sys/kernel/random/boot_id".
-func GetBootID() (ID128, error) {
-	if cachedBootID == (ID128{}) {
-		str, err := readfile("/proc/sys/kernel/random/boot_id")
-		if err != nil {
-			return ID128{}, err
-		}
-		id, err := ParseUUID(strings.TrimSuffix(str, "\n"))
-		if err != nil {
-			return ID128{}, err
-		}
-		cachedBootID = id
-	}
-	return cachedBootID, nil
-}
-
-var cachedInvocationID ID128
-
-// GetInvocationID returns a unique identifier for this invocation of
-// the currently executed service.
-//
-// This is read from the "INVOCATION_ID" environment variable, which
-// is expected to be set by the service manager.
-//
-// The error returned is ErrNone if the service manager did not set
-// INVOCATION_ID, or ErrInvalid if the value of INVOCATION_ID could
-// not be parsed.
-func GetInvocationID() (ID128, error) {
-	if cachedInvocationID == (ID128{}) {
-		// BUG(lukeshu): GetInvocationID should distrust the
-		// environment in certain situations, similarly to GNU
-		// libc secure_getenv.
-		str, have := os.LookupEnv("INVOCATION_ID")
-		if !have {
-			return ID128{}, ErrNone
-		}
-		t, err := Parse(str)
-		if err != nil {
-			return ID128{}, err
-		}
-		cachedInvocationID = t
-	}
-	return cachedInvocationID, nil
-}