Call character checking function with unsigned char

See https://wiki.sei.cmu.edu/confluence/display/c/STR37-C.+Arguments+to+character-handling+functions+must+be+representable+as+an+unsigned+char

1 files changed, 1 insertions, 1 deletions

diff --git a/Panel.c b/Panel.c
index b77483d9..315f3887 100644
--- a/Panel.c
+++ b/Panel.c
@@ -411,7 +411,7 @@ HandlerResult Panel_selectByTyping(Panel* this, int ch) {
       this->eventHandlerState = xCalloc(100, sizeof(char));
    char* buffer = this->eventHandlerState;
 
-   if (ch > 0 && ch < 255 && isalnum(ch)) {
+   if (0 < ch && ch < 255 && isalnum((unsigned char)ch)) {
       int len = strlen(buffer);
       if (len < 99) {
          buffer[len] = ch;