cmd/geth: support string (non-hex) keys in db get/put/delete (#23744)

Adds suppor for passing regular strings to db `put`/`get`/`delete`, to avoid having to hex-encode when operating on fixed-key items like `SnapshotSyncStatus`, `SnapshotRecovery`  etc.
Signed-off-by: Maxim Zhiburt <zhiburt@gmail.com>
Co-authored-by: Martin Holst Swende <martin@swende.se>

cmd/geth/dbcmd.go

@@ -17,6 +17,7 @@
 package main
 
 import (
+	"errors"
 	"fmt"
 	"os"
 	"path/filepath"
@@ -335,14 +336,15 @@ func dbGet(ctx *cli.Context) error {
 	db := utils.MakeChainDatabase(ctx, stack, true)
 	defer db.Close()
 
-	key, err := hexutil.Decode(ctx.Args().Get(0))
+	key, err := parseHexOrString(ctx.Args().Get(0))
 	if err != nil {
 		log.Info("Could not decode the key", "error", err)
 		return err
 	}
+
 	data, err := db.Get(key)
 	if err != nil {
-		log.Info("Get operation failed", "error", err)
+		log.Info("Get operation failed", "key", fmt.Sprintf("0x%#x", key), "error", err)
 		return err
 	}
 	fmt.Printf("key %#x: %#x\n", key, data)
@@ -360,7 +362,7 @@ func dbDelete(ctx *cli.Context) error {
 	db := utils.MakeChainDatabase(ctx, stack, false)
 	defer db.Close()
 
-	key, err := hexutil.Decode(ctx.Args().Get(0))
+	key, err := parseHexOrString(ctx.Args().Get(0))
 	if err != nil {
 		log.Info("Could not decode the key", "error", err)
 		return err
@@ -370,7 +372,7 @@ func dbDelete(ctx *cli.Context) error {
 		fmt.Printf("Previous value: %#x\n", data)
 	}
 	if err = db.Delete(key); err != nil {
-		log.Info("Delete operation returned an error", "error", err)
+		log.Info("Delete operation returned an error", "key", fmt.Sprintf("0x%#x", key), "error", err)
 		return err
 	}
 	return nil
@@ -393,7 +395,7 @@ func dbPut(ctx *cli.Context) error {
 		data  []byte
 		err   error
 	)
-	key, err = hexutil.Decode(ctx.Args().Get(0))
+	key, err = parseHexOrString(ctx.Args().Get(0))
 	if err != nil {
 		log.Info("Could not decode the key", "error", err)
 		return err
@@ -499,3 +501,12 @@ func freezerInspect(ctx *cli.Context) error {
 	}
 	return nil
 }
+
+// ParseHexOrString tries to hexdecode b, but if the prefix is missing, it instead just returns the raw bytes
+func parseHexOrString(str string) ([]byte, error) {
+	b, err := hexutil.Decode(str)
+	if errors.Is(err, hexutil.ErrMissingPrefix) {
+		return []byte(str), nil
+	}
+	return b, err
+}