Modify API configuration.

  C API mrb_p() is always callable.
  - But it will do nothing when ENABLE_STDIO is not defined.

  Kernel#__printstr__ is always callable.
  - But it will do nothing when ENABLE_STDIO is not defined.

src/error.c

@@ -208,9 +208,7 @@ mrb_exc_raise(mrb_state *mrb, mrb_value exc)
   mrb->exc = (struct RObject*)mrb_object(exc);
   exc_debug_info(mrb, mrb->exc);
   if (!mrb->jmp) {
-#ifdef ENABLE_STDIO
     mrb_p(mrb, exc);
-#endif
     abort();
   }
   longjmp(*(jmp_buf*)mrb->jmp, 1);

src/print.c

@@ -5,12 +5,12 @@
 */
 
 #include "mruby.h"
-#ifdef ENABLE_STDIO
 #include "mruby/string.h"
 
 static void
 printstr(mrb_state *mrb, mrb_value obj)
 {
+#ifdef ENABLE_STDIO
   struct RString *str;
   char *s;
   int len;
@@ -21,14 +21,17 @@ printstr(mrb_state *mrb, mrb_value obj)
     len = str->len;
     fwrite(s, len, 1, stdout);
   }
+#endif
 }
 
 void
 mrb_p(mrb_state *mrb, mrb_value obj)
 {
+#ifdef ENABLE_STDIO
   obj = mrb_funcall(mrb, obj, "inspect", 0);
   printstr(mrb, obj);
   putc('\n', stdout);
+#endif
 }
 
 /* 15.3.1.2.9  */
@@ -54,31 +57,22 @@ mrb_init_print(mrb_state *mrb)
   mrb_define_method(mrb, krn, "__printstr__", mrb_printstr, ARGS_REQ(1));
 }
 
-
 void
 mrb_show_version(mrb_state *mrb)
 {
-  printf("mruby - Embeddable Ruby  Copyright (c) 2010-2013 mruby developers\n");
-}
+  static const char version_msg[] = "mruby - Embeddable Ruby  Copyright (c) 2010-2013 mruby developers\n";
+  mrb_value msg;
 
-void
-mrb_show_copyright(mrb_state *mrb)
-{
-  printf("mruby - Copyright (c) 2010-2013 mruby developers\n");
-}
-#else
-void
-mrb_p(mrb_state *mrb, mrb_value obj)
-{
-}
-
-void
-mrb_show_version(mrb_state *mrb)
-{
+  msg = mrb_str_new(mrb, version_msg, sizeof(version_msg) - 1);
+  printstr(mrb, msg);
 }
 
 void
 mrb_show_copyright(mrb_state *mrb)
 {
+  static const char copyright_msg[] = "mruby - Copyright (c) 2010-2013 mruby developers\n";
+  mrb_value msg;
+
+  msg = mrb_str_new(mrb, copyright_msg, sizeof(copyright_msg) - 1);
+  printstr(mrb, msg);
 }
-#endif