enc: fromHexChar -> HexCharToDec

* enc/b64.go (fromHexChar): Move and rename this function to...
* enc/hex.go (HexCharToDec): ...this.

1 files changed, 3 insertions, 15 deletions

diff --git a/enc/b64.go b/enc/b64.go
index 1e49b58..4c251a2 100644
--- a/enc/b64.go
+++ b/enc/b64.go
@@ -10,9 +10,9 @@ func HexToBase64(hex string) string {
 
 	b64 := ""
 	for i := 0; i <= len(hb)-3; i = i + 3 {
-		a := (fromHexChar(hb[i])<<8 |
-			fromHexChar(hb[i+1])<<4 |
-			fromHexChar(hb[i+2]))
+		a := (HexCharToDec(hb[i])<<8 |
+			HexCharToDec(hb[i+1])<<4 |
+			HexCharToDec(hb[i+2]))
 		b64 += encode(a >> 6)
 		b64 += encode(a & 0b111111)
 	}
@@ -22,15 +22,3 @@ func HexToBase64(hex string) string {
 func encode(b uint16) string {
 	return string(b64_table[b])
 }
-
-// Adapted from
-// https://go.googlesource.com/go/+/refs/tags/go1.15/src/encoding/hex/hex.go#83
-func fromHexChar(c byte) uint16 {
-	switch {
-	case '0' <= c && c <= '9':
-		return uint16(c - '0')
-	case 'a' <= c && c <= 'f':
-		return uint16(c - 'a' + 10)
-	}
-	return 0
-}