Add version to btcctl.

This commit adds version information to btcctl.  The plan is to keep
it in lock step with the btcd version.  It also updates the release script
so the version file is updated automatically with the btcd one.

release/prep_release.sh

@@ -26,6 +26,7 @@ PROJECT=btcd
 PROJECT_UC=$(echo $PROJECT | tr '[:lower:]' '[:upper:]')
 SCRIPT=$(basename $0)
 VERFILE=../version.go
+VERFILES="$VERFILE ../util/btcctl/version.go"
 PROJ_CHANGES=../CHANGES
 
 # verify params
@@ -37,11 +38,13 @@ fi
 CUR_DIR=$(pwd)
 cd "$(dirname $0)"
 
-# verify version file exists
-if [ ! -f "$VERFILE" ]; then
-	echo "$SCRIPT: error: $VERFILE does not exist" 1>&2
-	exit 1
-fi
+# verify version files exist
+for verfile in $VERFILES; do
+	if [ ! -f "$verfile" ]; then
+		echo "$SCRIPT: error: $verfile does not exist" 1>&2
+		exit 1
+	fi
+done
 
 # verify changes file exists
 if [ ! -f "$PROJ_CHANGES" ]; then
@@ -172,17 +175,21 @@ awk '
 second_line==1 { print $0 }
 ' <"$PROJ_CHANGES" >>"${PROJ_CHANGES}.tmp"
 
-# update version file with new version
-sed -E "
-    s/${PAT_PREFIX}Major${PAT_SUFFIX}/\1${MAJOR}/;
-    s/${PAT_PREFIX}Minor${PAT_SUFFIX}/\1${MINOR}/;
-    s/${PAT_PREFIX}Patch${PAT_SUFFIX}/\1${PATCH}/;
-" <"$VERFILE" >"${VERFILE}.tmp"
+# update version filef with new version
+for verfile in $VERFILES; do
+	sed -E "
+	    s/${PAT_PREFIX}Major${PAT_SUFFIX}/\1${MAJOR}/;
+	    s/${PAT_PREFIX}Minor${PAT_SUFFIX}/\1${MINOR}/;
+	    s/${PAT_PREFIX}Patch${PAT_SUFFIX}/\1${PATCH}/;
+	" <"$verfile" >"${verfile}.tmp"
+done
 
 
 # Apply changes
 mv "${PROJ_CHANGES}.tmp" "$PROJ_CHANGES"
-mv "${VERFILE}.tmp" "$VERFILE"
+for verfile in $VERFILES; do
+	mv "${verfile}.tmp" "$verfile"
+done
 
 echo "All files have been prepared for release."
 echo "Use the following commands to review the changes for accuracy:"

util/btcctl/config.go

@@ -6,6 +6,7 @@ import (
 	"github.com/conformal/go-flags"
 	"os"
 	"path/filepath"
+	"strings"
 )
 
 var (
@@ -19,6 +20,7 @@ var (
 //
 // See loadConfig for details on the configuration load process.
 type config struct {
+	ShowVersion   bool   `short:"V" long:"version" description:"Display version information and exit"`
 	ConfigFile    string `short:"C" long:"configfile" description:"Path to configuration file"`
 	RpcUser       string `short:"u" long:"rpcuser" description:"RPC username"`
 	RpcPassword   string `short:"P" long:"rpcpass" default-mask:"-" description:"RPC password"`
@@ -48,12 +50,20 @@ func loadConfig() (*flags.Parser, *config, []string, error) {
 	}
 
 	// Pre-parse the command line options to see if an alternative config
-	// file was specified.  Any errors can be ignored here since they will
-	// be caught be the final parse below.
+	// file or the version flag was specified.  Any errors can be ignored
+	// here since they will be caught be the final parse below.
 	preCfg := cfg
 	preParser := flags.NewParser(&preCfg, flags.None)
 	preParser.Parse()
 
+	// Show the version and exit if the version flag was specified.
+	if preCfg.ShowVersion {
+		appName := filepath.Base(os.Args[0])
+		appName = strings.TrimSuffix(appName, filepath.Ext(appName))
+		fmt.Println(appName, "version", version())
+		os.Exit(0)
+	}
+
 	// Load additional config from file.
 	parser := flags.NewParser(&cfg, flags.PassDoubleDash|flags.HelpFlag)
 	err := parser.ParseIniFile(preCfg.ConfigFile)

util/btcctl/version.go

@@ -0,0 +1,72 @@
+// 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 = 3
+	appPatch uint = 3
+
+	// appPreRelease MUST only contain characters from semanticAlphabet
+	// per the semantic versioning spec.
+	appPreRelease = "alpha"
+)
+
+// 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) {
+			result.WriteRune(r)
+		}
+	}
+	return result.String()
+}