Introduce a new lp.cdefs.h file, which will be used to make it

somewhat easier to build this lpr on other operating systems.
This simply includes <sys/cdefs.h> when that is appropriate,
and then checks for any cdefs-ish macros that lpr uses, and
defines them if they don't already exist.  This is only a start
at making freebsd's lpr less of a hassle to port.  It is mainly
added so all of lpr can be changed to use the __FBSDID() macro,
without making it *more* of a hassle to build on other OS's.

Reviewed by:	discussed with bde and obrien
MFC after:	15 days

usr.sbin/lpr/common_source/lp.cdefs.h

@@ -0,0 +1,107 @@
+/*-
+ * ------+---------+---------+---------+---------+---------+---------+---------*
+ * Copyright (c) 2003  - Garance Alistair Drosehn <gad@FreeBSD.org>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in the
+ *      documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation
+ * are those of the authors and should not be interpreted as representing
+ * official policies, either expressed or implied, of the FreeBSD Project.
+ *
+ * ------+---------+---------+---------+---------+---------+---------+---------*
+ * $FreeBSD$
+ * ------+---------+---------+---------+---------+---------+---------+---------*
+ */
+
+/*
+ * The main goal of this include file is to provide a platform-neutral way
+ * to define some macros that lpr wants from FreeBSD's <sys/cdefs.h>.  This
+ * will simply use the standard <sys/cdefs.h> when compiled in FreeBSD, but
+ * other OS's may not have /usr/include/sys/cdefs.h (or even if that file
+ * exists, it may not define all the macros that lpr will use).
+ */
+
+#if !defined(_LP_CDEFS_H_)
+#define	_LP_CDEFS_H_
+
+/*
+ * For non-BSD platforms, you can compile lpr with -DHAVE_SYS_CDEFS_H
+ * if <sys/cdefs.h> should be included.
+ */
+#if defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)
+#  define HAVE_SYS_CDEFS_H
+#endif
+#if defined(HAVE_SYS_CDEFS_H)
+#  include <sys/cdefs.h>
+#endif
+
+/*
+ * __unused is a compiler-specific trick which can be used to avoid
+ * warnings about a variable which is defined but never referenced.
+ * Some lpr files use this, so define a null version if it was not
+ * defined by <sys/cdefs.h>.
+ */
+#if !defined(__unused)
+#  define	__unused
+#endif
+
+/*
+ * All the lpr source files will want to reference __FBSDID() to
+ * handle rcs id's.
+ */
+#if !defined(__FBSDID)
+#  if defined(lint) || defined(STRIP_FBSDID)
+#    define	__FBSDID(s)	struct skip_rcsid_struct
+#  elif defined(__IDSTRING)			/* NetBSD */
+#    define	__FBSDID(s)	__IDSTRING(rcsid,s)
+#  else
+#    define	__FBSDID(s)	static const char rcsid[] __unused = s
+#  endif
+#endif /* __FBSDID */
+
+/*
+ * Some lpr include files use __BEGIN_DECLS and __END_DECLS.
+ */
+#if !defined(__BEGIN_DECLS)
+#  if defined(__cplusplus)
+#    define	__BEGIN_DECLS	extern "C" {
+#    define	__END_DECLS	}
+#  else
+#    define	__BEGIN_DECLS
+#    define	__END_DECLS
+#  endif
+#endif
+
+/*
+ * __printflike and __printf0like are a compiler-specific tricks to
+ * tell the compiler to check the format-codes in printf-like
+ * routines wrt the args that will be formatted.
+ */
+#if !defined(__printflike)
+#  define	__printflike(fmtarg, firstvararg)
+#endif
+#if !defined(__printf0like)
+#  define	__printf0like(fmtarg, firstvararg)
+#endif
+
+#endif /* !_LP_CDEFS_H_ */