C23: use AC_HEADER_STDBOOL #include <stdbool.h>

scripts/configure.in

@@ -129,6 +129,9 @@ AC_C_BIGENDIAN
 dnl Check for required header files
 AC_HEADER_STDC
 
+dnl Check for compiler bool support
+AC_HEADER_STDBOOL
+
 dnl Need either setenv or putenv
 AC_CHECK_FUNCS(setenv putenv)
 

utils/magic.h

@@ -85,14 +85,7 @@ typedef pointertype ClientData;
 
 /* --------------------------- Booleans ------------------------------- */
 
-typedef unsigned char bool;
-
-#ifndef TRUE
-#define	TRUE	((bool)1)
-#endif
-#ifndef FALSE
-#define	FALSE	((bool)0)
-#endif
+#include "utils/magic_stdbool.h"
 
 /* ----------------------- Simple functions --------------------------- */
 

utils/magic_stdbool.h

@@ -0,0 +1,101 @@
+/*
+ *  utils/magic_stdbool.h
+ *
+ *  Copyright (C) 1985, 1990 Regents of the University of California.
+ *
+ *  Permission to use, copy, modify, and distribute this
+ *  software and its documentation for any purpose and without
+ *  fee is hereby granted, provided that the above copyright
+ *  notice appear in all copies.  The University of California
+ *  makes no representations about the suitability of this
+ *  software for any purpose.  It is provided "as is" without
+ *  express or implied warranty.  Export of this software outside
+ *  of the United States of America may require an export license.
+ *
+ *  SPDX-License-Identifier: HPND-UC-export-US
+ *
+ *
+ *  This file contains code snippets that are part of the GNU autoconf 2.69
+ *  project documentation.  This project is licensed under GPLv3 with a
+ *  Section 7 clause outlined in autoconf-2.69/COPYING.EXCEPTION.
+ *
+ *  The documentation for the autoconf project is licensed under GNU Free
+ *  Documentation License Version 1.3 or any later version published by the
+ *  Free Software Foundation.  The snippets in here are taken entirely from the
+ *  documentation so fall under GFDL-1.3-or-later terms.
+ *  The documentation published by the FSF can be seen at
+ *   https://www.gnu.org/savannah-checkouts/gnu/autoconf/manual/autoconf-2.69/autoconf.html
+ *  This section seeks to provide attribution by providing references to the source
+ *  a link to the full license text and the required boilerplate text directly below:
+ *
+ *  Copyright (C) 1992-1996, 1998-2012 Free Software Foundation, Inc.
+ *
+ *    Permission is granted to copy, distribute and/or modify this
+ *    document under the terms of the GNU Free Documentation License,
+ *    Version 1.3 or any later version published by the Free Software
+ *    Foundation; with no Invariant Sections, no Front-Cover texts, and
+ *    no Back-Cover Texts.  A copy of the license is included in the
+ *    section entitled "GNU Free Documentation License."
+ *
+ *  A full copy of the GNU Free Documentation License version 1.3 is available at:
+ *    https://www.gnu.org/licenses/fdl-1.3.html
+ *  SPDX-License-Identifier: GFDL-1.3-or-later
+ *
+ *
+ *  All other lines in this file are licensed under the HPND-UC-export-US license
+ *  at the top of this file inline with the main project licensing.
+ *
+ */
+
+#ifndef _MAGIC__UTILS__MAGIC_STDBOOL_H
+#define _MAGIC__UTILS__MAGIC_STDBOOL_H
+
+#ifdef HAVE_MAGIC_AUTOCONF_CONFIG_H
+#include "magic/autoconf/config.h"
+#endif
+
+/* This section is taken from autoconf-2.69 manual
+ * https://www.gnu.org/software/autoconf/manual/autoconf-2.69/html_node/Particular-Headers.html
+ * for HAVE_STDBOOL_H
+ */
+#ifdef HAVE_STDBOOL_H
+ # include <stdbool.h>
+
+ #ifndef TRUE
+  #define	TRUE	(true)
+ #endif
+ #ifndef FALSE
+  #define	FALSE	(false)
+ #endif
+#else
+ # ifndef HAVE__BOOL
+ #  ifdef __cplusplus
+ typedef bool _Bool;
+ #  else
+ #   define _Bool signed char
+ #  endif
+ # endif
+ # define bool _Bool
+ # define false 0
+ # define true 1
+ # define __bool_true_false_are_defined 1
+
+/* This section is taken from magic project, see historical magic.h */
+ /* originally magic.h used unsigned char but should be source compatible with
+  *  a real bool type such as that in C23/C++
+  */
+
+ /*typedef unsigned char bool;*/
+/* commented out the original magic definition to adopt the historical C
+ *  standard definition provided above.
+ */
+
+ #ifndef TRUE
+  #define	TRUE	((bool)1)
+ #endif
+ #ifndef FALSE
+  #define	FALSE	((bool)0)
+ #endif
+#endif
+
+#endif /* _MAGIC__UTILS__MAGIC_STDBOOL_H */