1 files changed, 79 insertions, 0 deletions
diff --git a/internal/fmtio/fmtio.go b/internal/fmtio/fmtio.go
new file mode 100644
index 0000000..0e252d4
--- /dev/null
+++ b/internal/fmtio/fmtio.go
@@ -0,0 +1,79 @@
+// package fmtio provides basic utilities to format input and output
+package fmtio
+
+import (
+	"bytes"
+	"crypto"
+	"crypto/ed25519"
+	"fmt"
+	"io/ioutil"
+	"os"
+
+	"git.sigsum.org/sigsum-go/pkg/hex"
+	"git.sigsum.org/sigsum-go/pkg/types"
+)
+
+func BytesFromStdin() ([]byte, error) {
+	b, err := ioutil.ReadAll(os.Stdin)
+	if err != nil {
+		return nil, err
+	}
+	return b, nil
+}
+
+// StringFromStdin reads bytes from stdin, parsing them as a string without
+// leading and trailing white space
+func StringFromStdin() (string, error) {
+	b, err := ioutil.ReadAll(os.Stdin)
+	if err != nil {
+		return "", err
+	}
+	return string(bytes.TrimSpace(b)), nil
+}
+
+func SignerFromHex(s string) (crypto.Signer, error) {
+	b, err := hex.Deserialize(s)
+	if err != nil {
+		return nil, err
+	}
+	if n := len(b); n != ed25519.PrivateKeySize {
+		return nil, fmt.Errorf("invalid size %d", n)
+	}
+	return ed25519.PrivateKey(b), nil
+}
+
+func PublicKeyFromHex(s string) (pub types.PublicKey, err error) {
+	b, err := hex.Deserialize(s)
+	if err != nil {
+		return pub, err
+	}
+	if n := len(b); n != types.PublicKeySize {
+		return pub, fmt.Errorf("invalid size %d", n)
+	}
+	copy(pub[:], b)
+	return
+}
+
+func KeyHashFromHex(s string) (h types.Hash, err error) {
+	b, err := hex.Deserialize(s)
+	if err != nil {
+		return h, err
+	}
+	if n := len(b); n != types.HashSize {
+		return h, fmt.Errorf("invalid size %d", n)
+	}
+	copy(h[:], b)
+	return
+}
+
+func SignatureFromHex(s string) (sig types.Signature, err error) {
+	b, err := hex.Deserialize(s)
+	if err != nil {
+		return sig, err
+	}
+	if n := len(b); n != types.SignatureSize {
+		return sig, fmt.Errorf("invalid size %d", n)
+	}
+	copy(sig[:], b)
+	return
+}