lbcd/util/btcctl/version.go
2014-09-20 13:00:02 -05:00

75 lines
2.5 KiB
Go

// Copyright (c) 2013 Conformal Systems LLC.
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
package main
import (
"bytes"
"fmt"
"strings"
)
// semanticAlphabet
const semanticAlphabet = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-"
// These constants define the application version and follow the semantic
// versioning 2.0.0 spec (http://semver.org/).
const (
appMajor uint = 0
appMinor uint = 9
appPatch uint = 0
// appPreRelease MUST only contain characters from semanticAlphabet
// per the semantic versioning spec.
appPreRelease = "beta"
)
// appBuild is defined as a variable so it can be overridden during the build
// process with '-ldflags "-X main.appBuild foo' if needed. It MUST only
// contain characters from semanticAlphabet per the semantic versioning spec.
var appBuild string
// version returns the application version as a properly formed string per the
// semantic versioning 2.0.0 spec (http://semver.org/).
func version() string {
// Start with the major, minor, and patch versions.
version := fmt.Sprintf("%d.%d.%d", appMajor, appMinor, appPatch)
// Append pre-release version if there is one. The hyphen called for
// by the semantic versioning spec is automatically appended and should
// not be contained in the pre-release string. The pre-release version
// is not appended if it contains invalid characters.
preRelease := normalizeVerString(appPreRelease)
if preRelease != "" {
version = fmt.Sprintf("%s-%s", version, preRelease)
}
// Append build metadata if there is any. The plus called for
// by the semantic versioning spec is automatically appended and should
// not be contained in the build metadata string. The build metadata
// string is not appended if it contains invalid characters.
build := normalizeVerString(appBuild)
if build != "" {
version = fmt.Sprintf("%s+%s", version, build)
}
return version
}
// normalizeVerString returns the passed string stripped of all characters which
// are not valid according to the semantic versioning guidelines for pre-release
// version and build metadata strings. In particular they MUST only contain
// characters in semanticAlphabet.
func normalizeVerString(str string) string {
var result bytes.Buffer
for _, r := range str {
if strings.ContainsRune(semanticAlphabet, r) {
// Ignoring the error here since it can only fail if
// the the system is out of memory and there are much
// bigger issues at that point.
_, _ = result.WriteRune(r)
}
}
return result.String()
}