b64decode correct decode of some strings

https://github.com/warmcat/libwebsockets/issues/467



Signed-off-by: Andy Green <andy@warmcat.com>

lib/base64-decode.c

@@ -99,7 +99,7 @@ LWS_VISIBLE int
 lws_b64_decode_string(const char *in, char *out, int out_size)
 {
 	int len;
-	int i;
+	int i, c;
 	int done = 0;
 	unsigned char v;
 	unsigned char quad[4];
@@ -110,20 +110,20 @@ lws_b64_decode_string(const char *in, char *out, int out_size)
 		for (i = 0; i < 4 && *in; i++) {
 
 			v = 0;
+			c = 0;
 			while (*in && !v) {
-
-				v = *in++;
+				c = v = *in++;
 				v = (v < 43 || v > 122) ? 0 : decode[v - 43];
 				if (v)
 					v = (v == '$') ? 0 : v - 61;
-				if (*in) {
+			}
+			if (c) {
 				len++;
 				if (v)
 					quad[i] = v - 1;
 			} else
 				quad[i] = 0;
 		}
-		}
 
 		if (out_size < (done + len - 1))
 			/* out buffer is too small */
@@ -147,6 +147,7 @@ lws_b64_decode_string(const char *in, char *out, int out_size)
 	return done;
 }
 
+#if 0
 int
 lws_b64_selftest(void)
 {
@@ -183,3 +184,4 @@ lws_b64_selftest(void)
 
 	return 0;
 }
+#endif