Make sure to use unsigned char for is*() functions
On some platforms, the implementation is such that a signed char
triggers a warning when used with is*() functions. On others, the
behavior is outright buggy when presented with a char that happens
to get promoted to a negative integer.
The safest thing is to cast the char that's used to an unsigned char.
Reviewed-by: Andy Polyakov <appro@openssl.org>
diff --git a/apps/s_server.c b/apps/s_server.c
index 489924c..3803036 100644
--- a/apps/s_server.c
+++ b/apps/s_server.c
@@ -1380,7 +1380,7 @@
case OPT_PSK:
#ifndef OPENSSL_NO_PSK
for (p = psk_key = opt_arg(); *p; p++) {
- if (isxdigit(*p))
+ if (isxdigit(_UC(*p)))
continue;
BIO_printf(bio_err, "Not a hex number '%s'\n", *argv);
goto end;
