optlist.h

Currently, options.c is the only file that #includes "optlist.h".

In theory, if a source file did want to include optlist.h (perhaps
for the struct allopt_t declaration so they could deal with a
pointer to such a struct), they wouldn't be able to include it
because of a static function prototype that it contains.

Add some protection to only include that static function
prototype when optlist.h is included from options.c.

include/optlist.h

@@ -4,6 +4,10 @@
 #ifndef OPTLIST_H
 #define OPTLIST_H
 
+#ifdef OPTIONS_C
+static int optfn_boolean(int, int, boolean, char *, char *);
+#endif
+
 /*
  *  NOTE:  If you add (or delete) an option, please review:
  *             doc/options.txt
@@ -12,7 +16,6 @@
  *         updates that should accompany your change.
  */
 
-static int optfn_boolean(int, int, boolean, char *, char *);
 enum OptType { BoolOpt, CompOpt, OthrOpt };
 enum Y_N { No, Yes };
 enum Off_On { Off, On };

src/options.c

@@ -50,6 +50,8 @@ NEARDATA struct instance_flags iflags; /* provide linkage */
  *
  */
 
+#define OPTIONS_C
+
 #define NHOPT_PROTO
 #include "optlist.h"
 #undef NHOPT_PROTO
@@ -72,6 +74,7 @@ static struct allopt_t allopt_init[] = {
 };
 #undef NHOPT_PARSE
 
+#undef OPTIONS_C
 
 #define PILE_LIMIT_DFLT 5
 #define rolestring(val, array, field) \