two more wrapper macros for ctype.h

we need them on the platform where 'char' is signed.

2 files changed, 6 insertions, 4 deletions

diff --git a/include/mruby.h b/include/mruby.h
index 2f2f3753d..b741e6444 100644
--- a/include/mruby.h
+++ b/include/mruby.h
@@ -274,6 +274,8 @@ mrb_value mrb_check_funcall(mrb_state *mrb, mrb_value recv, mrb_sym mid, int arg
 #define ISALPHA(c) (ISASCII(c) && isalpha((int)(unsigned char)(c)))
 #define ISDIGIT(c) (ISASCII(c) && isdigit((int)(unsigned char)(c)))
 #define ISXDIGIT(c) (ISASCII(c) && isxdigit((int)(unsigned char)(c)))
+#define TOUPPER(c) (ISASCII(c) ? toupper((int)(unsigned char)(c)) : (c))
+#define TOLOWER(c) (ISASCII(c) ? tolower((int)(unsigned char)(c)) : (c))
 #endif
 
 mrb_value mrb_exc_new(mrb_state *mrb, struct RClass *c, const char *ptr, long len);
diff --git a/src/string.c b/src/string.c
index d8fe56790..7077e9dfd 100644
--- a/src/string.c
+++ b/src/string.c
@@ -866,12 +866,12 @@ mrb_str_capitalize_bang(mrb_state *mrb, mrb_value str)
   if (s->len == 0 || !s->ptr) return mrb_nil_value();
   p = s->ptr; pend = s->ptr + s->len;
   if (ISLOWER(*p)) {
-    *p = toupper(*p);
+    *p = TOUPPER(*p);
     modify = 1;
   }
   while (++p < pend) {
     if (ISUPPER(*p)) {
-      *p = tolower(*p);
+      *p = TOLOWER(*p);
       modify = 1;
     }
   }
@@ -1079,7 +1079,7 @@ mrb_str_downcase_bang(mrb_state *mrb, mrb_value str)
   pend = s->ptr + s->len;
   while (p < pend) {
     if (ISUPPER(*p)) {
-      *p = tolower(*p);
+      *p = TOLOWER(*p);
       modify = 1;
     }
     p++;
@@ -2744,7 +2744,7 @@ mrb_str_upcase_bang(mrb_state *mrb, mrb_value str)
   pend = RSTRING_END(str);
   while (p < pend) {
     if (ISLOWER(*p)) {
-      *p = toupper(*p);
+      *p = TOUPPER(*p);
       modify = 1;
     }
     p++;