http://ftp.x.org/contrib/applications/xscreensaver-3.21.tar.gz

[xscreensaver] / utils / yarandom.h

diff --git a/utils/yarandom.h b/utils/yarandom.h
index 53b22fd88d0196d886da4cf270a7fcca65206bbb..0e1dfcfb7619112ea1d7d21b233062488800b1ce 100644 (file)
--- a/utils/yarandom.h
+++ b/utils/yarandom.h
@@ -1,19 +1,64 @@
+/* xscreensaver, Copyright (c) 1997, 1998 by Jamie Zawinski <jwz@jwz.org>
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that
+ * copyright notice and this permission notice appear in supporting
+ * documentation.  No representations are made about the suitability of this
+ * software for any purpose.  It is provided "as is" without express or 
+ * implied warranty.
+ */
+
+#ifndef __YARANDOM_H__
+#define __YARANDOM_H__
+
 #undef random
 #undef rand
 #undef drand48
 #undef srandom
 #undef srand
 #undef srand48
+#undef frand
+#undef RAND_MAX
+
+#ifdef VMS
+# include "vms-gtod.h"
+#endif
+
+extern unsigned int ya_random (void);
+extern void ya_rand_init (unsigned int);
 
 #define random()   ya_random()
-#define srandom(i) ya_rand_init(0)
+#define RAND_MAX   0x7FFFFFFF
 
-#undef P
-#if __STDC__
-# define P(x)x
-#else
-# define P(x)()
-#endif
+/*#define srandom(i) ya_rand_init(0)*/
+
+/* Define these away to keep people from using the wrong APIs in xscreensaver.
+ */
+#define rand          __ERROR_use_random_not_rand_in_xscreensaver__
+#define drand48       __ERROR_use_random_not_drand48_in_xscreensaver__
+#define srandom       __ERROR_do_not_call_srandom_in_xscreensaver__
+#define srand         __ERROR_do_not_call_srand_in_xscreensaver__
+#define srand48       __ERROR_do_not_call_srand48_in_xscreensaver__
+#define ya_rand_init  __ERROR_do_not_call_ya_rand_init_in_xscreensaver__
+
+
+#if defined (__GNUC__) && (__GNUC__ >= 2)
+ /* Implement frand using GCC's statement-expression extension. */
+
+# define frand(f)                                                      \
+  ({ double tmp = (((double) random()) /                               \
+                  (((double) ((unsigned int)~0)) / ((double) (f))));   \
+     tmp < 0 ? (-tmp) : tmp; })
+
+#else /* not GCC2 - implement frand using a global variable.*/
+
+static double _frand_tmp_;
+# define frand(f)                                                      \
+  (_frand_tmp_ = (((double) random()) /                                \
+                 (((double) ((unsigned int)~0)) / ((double) (f)))),    \
+   _frand_tmp_ < 0 ? (-_frand_tmp_) : _frand_tmp_)
+
+#endif /* not GCC2 */
 
-extern unsigned int ya_random P((void));
-extern void ya_rand_init P((unsigned int));
+#endif /* __YARANDOM_H__ */