From 745aeba382ffd0600a9f1e1ef1252d870b2295d5 Mon Sep 17 00:00:00 2001
From: Craig Barnes <craigbarnes@protonmail.com>
Date: Sat, 8 Aug 2020 03:55:23 +0100
Subject: [PATCH] base64: simplify is_valid() by using reverse_lookup table

---
 base64.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/base64.c b/base64.c
index 7e0ec0a1..214d6943 100644
--- a/base64.c
+++ b/base64.c
@@ -37,12 +37,9 @@ static const char lookup[64] = {
 };
 
 static inline bool
-is_valid(char c)
+is_valid(unsigned char c)
 {
-    return ((c >= 'A' && c <= 'Z') ||
-            (c >= 'a' && c <= 'z') ||
-            (c >= '0' && c <= '9') ||
-            c == '+' || c == '/' || c == '=');
+    return reverse_lookup[c] != 0 || c == 'A' || c == '=';
 }
 
 char *