cmd,extra: restore the Version link-time variable

We don't need it in our builds, but it's useful for downstream packagers.

Fixes #671
Updates NixOS/nixpkgs#474666
Updates golang/go#77020

cmd/age-inspect/inspect.go

@@ -24,6 +24,10 @@ Options:
 INPUT defaults to standard input. "-" may be used as INPUT to explicitly
 read from standard input.`
 
+// Version can be set at link time to override debug.BuildInfo.Main.Version when
+// building manually without git history. It should look like "v1.2.3".
+var Version string
+
 func main() {
 	flag.Usage = func() { fmt.Fprintf(os.Stderr, "%s\n", usage) }
 
@@ -37,11 +41,10 @@ func main() {
 	flag.Parse()
 
 	if versionFlag {
-		if buildInfo, ok := debug.ReadBuildInfo(); ok {
-			fmt.Println(buildInfo.Main.Version)
-			return
+		if buildInfo, ok := debug.ReadBuildInfo(); ok && Version == "" {
+			Version = buildInfo.Main.Version
 		}
-		fmt.Println("(unknown)")
+		fmt.Println(Version)
 		return
 	}
 

cmd/age-keygen/keygen.go

@@ -56,6 +56,10 @@ Examples:
     $ age-keygen -y key.txt
     age1ql3z7hjy54pw3hyww5ayyfg7zqgvc7w3j2elw8zmrj2kg5sfn9aqmcac8p`
 
+// Version can be set at link time to override debug.BuildInfo.Main.Version when
+// building manually without git history. It should look like "v1.2.3".
+var Version string
+
 func main() {
 	log.SetFlags(0)
 	flag.Usage = func() { fmt.Fprintf(os.Stderr, "%s\n", usage) }
@@ -69,6 +73,15 @@ func main() {
 	flag.StringVar(&outFlag, "o", "", "output to `FILE` (default stdout)")
 	flag.StringVar(&outFlag, "output", "", "output to `FILE` (default stdout)")
 	flag.Parse()
+
+	if versionFlag {
+		if buildInfo, ok := debug.ReadBuildInfo(); ok && Version == "" {
+			Version = buildInfo.Main.Version
+		}
+		fmt.Println(Version)
+		return
+	}
+
 	if len(flag.Args()) != 0 && !convertFlag {
 		errorf("too many arguments")
 	}
@@ -78,14 +91,6 @@ func main() {
 	if pqFlag && convertFlag {
 		errorf("-pq cannot be used with -y")
 	}
-	if versionFlag {
-		if buildInfo, ok := debug.ReadBuildInfo(); ok {
-			fmt.Println(buildInfo.Main.Version)
-			return
-		}
-		fmt.Println("(unknown)")
-		return
-	}
 
 	out := os.Stdout
 	if outFlag != "" {

cmd/age-plugin-batchpass/plugin-batchpass.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"log"
 	"os"
+	"runtime/debug"
 	"strconv"
 	"strings"
 
@@ -73,6 +74,10 @@ When decrypting, you can set AGE_PASSPHRASE_MAX_WORK_FACTOR to limit the
 maximum scrypt work factor accepted (between 1 and 30, default 30). This can
 be used to avoid very slow decryptions.`
 
+// Version can be set at link time to override debug.BuildInfo.Main.Version when
+// building manually without git history. It should look like "v1.2.3".
+var Version string
+
 func main() {
 	flag.Usage = func() { fmt.Fprintf(os.Stderr, "%s\n", usage) }
 
@@ -80,6 +85,19 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
+	p.RegisterFlags(nil)
+
+	versionFlag := flag.Bool("version", false, "print the version")
+	flag.Parse()
+
+	if *versionFlag {
+		if buildInfo, ok := debug.ReadBuildInfo(); ok && Version == "" {
+			Version = buildInfo.Main.Version
+		}
+		fmt.Println(Version)
+		return
+	}
+
 	p.HandleIdentityAsRecipient(func(data []byte) (age.Recipient, error) {
 		if len(data) != 0 {
 			return nil, fmt.Errorf("batchpass identity does not take any payload")

cmd/age/age.go

@@ -98,6 +98,10 @@ func (f *identityFlags) addPluginFlag(value string) error {
 	return nil
 }
 
+// Version can be set at link time to override debug.BuildInfo.Main.Version when
+// building manually without git history. It should look like "v1.2.3".
+var Version string
+
 func main() {
 	flag.Usage = func() { fmt.Fprintf(os.Stderr, "%s\n", usage) }
 
@@ -136,13 +140,10 @@ func main() {
 	flag.Parse()
 
 	if versionFlag {
-		if buildInfo, ok := debug.ReadBuildInfo(); ok {
-			// TODO: use buildInfo.Settings to prepare a pseudoversion such as
-			// v0.0.0-20210817164053-32db794688a5+dirty on Go 1.18+.
-			fmt.Println(buildInfo.Main.Version)
-			return
+		if buildInfo, ok := debug.ReadBuildInfo(); ok && Version == "" {
+			Version = buildInfo.Main.Version
 		}
-		fmt.Println("(unknown)")
+		fmt.Println(Version)
 		return
 	}
 

extra/age-plugin-pq/plugin-pq.go

@@ -30,12 +30,16 @@ implementation of age that supports plugins.
 Recipients work out of the box, while identities need to be converted to plugin
 identities with -identity. If OUTPUT already exists, it is not overwritten.`
 
+// Version can be set at link time to override debug.BuildInfo.Main.Version when
+// building manually without git history. It should look like "v1.2.3".
+var Version string
+
 func main() {
 	log.SetFlags(0)
 
 	p, err := plugin.New("pq")
 	if err != nil {
-		log.Fatal(err)
+		errorf("failed to create plugin: %v", err)
 	}
 	p.RegisterFlags(nil)
 
@@ -50,11 +54,10 @@ func main() {
 	flag.Parse()
 
 	if versionFlag {
-		if buildInfo, ok := debug.ReadBuildInfo(); ok {
-			fmt.Println(buildInfo.Main.Version)
-			return
+		if buildInfo, ok := debug.ReadBuildInfo(); ok && Version == "" {
+			Version = buildInfo.Main.Version
 		}
-		fmt.Println("(unknown)")
+		fmt.Println(Version)
 		return
 	}
 

extra/age-plugin-tag/plugin-tag.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"runtime/debug"
 
 	"filippo.io/age"
 	"filippo.io/age/plugin"
@@ -18,6 +19,10 @@ support to any version and implementation of age that supports plugins.
 Usually, tagged recipients are the public side of private keys held in hardware,
 where the identity side is handled by a different plugin.`
 
+// Version can be set at link time to override debug.BuildInfo.Main.Version when
+// building manually without git history. It should look like "v1.2.3".
+var Version string
+
 func main() {
 	flag.Usage = func() { fmt.Fprintf(os.Stderr, "%s\n", usage) }
 
@@ -25,8 +30,22 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
+	p.RegisterFlags(nil)
+
+	versionFlag := flag.Bool("version", false, "print the version")
+	flag.Parse()
+
+	if *versionFlag {
+		if buildInfo, ok := debug.ReadBuildInfo(); ok && Version == "" {
+			Version = buildInfo.Main.Version
+		}
+		fmt.Println(Version)
+		return
+	}
+
 	p.HandleRecipient(func(b []byte) (age.Recipient, error) {
 		return tag.NewClassicRecipient(b)
 	})
+
 	os.Exit(p.Main())
 }

extra/age-plugin-tagpq/plugin-tagpq.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"runtime/debug"
 
 	"filippo.io/age"
 	"filippo.io/age/plugin"
@@ -19,6 +20,10 @@ implementation of age that supports plugins.
 Usually, tagged recipients are the public side of private keys held in hardware,
 where the identity side is handled by a different plugin.`
 
+// Version can be set at link time to override debug.BuildInfo.Main.Version when
+// building manually without git history. It should look like "v1.2.3".
+var Version string
+
 func main() {
 	flag.Usage = func() { fmt.Fprintf(os.Stderr, "%s\n", usage) }
 
@@ -26,8 +31,22 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
+	p.RegisterFlags(nil)
+
+	versionFlag := flag.Bool("version", false, "print the version")
+	flag.Parse()
+
+	if *versionFlag {
+		if buildInfo, ok := debug.ReadBuildInfo(); ok && Version == "" {
+			Version = buildInfo.Main.Version
+		}
+		fmt.Println(Version)
+		return
+	}
+
 	p.HandleRecipient(func(b []byte) (age.Recipient, error) {
 		return tag.NewHybridRecipient(b)
 	})
+
 	os.Exit(p.Main())
 }