Merge RAND_REDESIGN into MAIN

1 files changed, 100 insertions, 31 deletions

diff --git a/ext/standard/php_rand.h b/ext/standard/php_rand.h
index b4d7e991d0..19686a8066 100644
--- a/ext/standard/php_rand.h
+++ b/ext/standard/php_rand.h
@@ -15,47 +15,116 @@
    | Authors: Rasmus Lerdorf <rasmus@lerdorf.on.ca>                       |
    |          Zeev Suraski <zeev@zend.com>                                |
    |          Pedro Melo <melo@ip.pt>                                     |
+   |          Jeroen van Wolffelaar <jeroen@php.net>                      |
    |                                                                      |
    | Based on code from: Shawn Cokus <Cokus@math.washington.edu>          |
    +----------------------------------------------------------------------+
  */
 /* $Id$ */
 
+/* Layout implementation random functions
+ *
+ * The PHPAPI contains these functions:
+ * - long php_rand()
+ * - long php_rand_range(long min, long max)
+ * - void php_srand()
+ * - long php_getrandmax()
+ *
+ * Note that it is not possible to choose the algoritm. This is done to
+ * give the user the possibility to control all randomness by means of
+ * srand()/php.ini in a portable and consistent way.
+ *
+ * rand.c: (the only rand*.c file with PHP_API and PHP_FUNCTION functions)
+ *
+ * - PHP_FUNCTION([mt_]srand)
+ *   +-> void php_srand(void)
+ *   +-> void php_srand2(long seed, int alg)
+ *       +-> (rand_sys.c) long php_rand_sys()
+ *       +-> (rand_mt.c ) long php_rand_mt()
+ *
+ * - PHP_FUNCTION([mt_]rand)
+ *   +-> long php_rand()
+ *       +-> (rand_sys.c) long php_rand_sys()
+ *       +-> (rand_mt.c ) long php_rand_mt()
+ *   +-> long php_rand_range(long min, long max)
+ *       +-> calls php_rand()
+ *       
+ * - PHP_FUNCTION([mt_]getrandmax)
+ *   +-> PHPAPI long php_randmax(void)
+ *       +-> (rand_sys.c) long php_randmax_sys()
+ *       +-> (rand_mt.c ) long php_randmax_mt()
+ *   
+ *   --Jeroen
+ */
+
+/* TODO:
+ * - make constants available to PHP-user
+ * - MINFO section about which random number generators are available
+ * - Nuke randmax by enhancing PHP_RAND_RANGE to work well in the case of a
+ *   greater request than the real (internal) randmax is
+ * - Implement LCG
+ * - Implement a real-random source? (via internet, and/or /dev/urandom?)
+ * - Can lrand48 be thread-safe?
+ * - Is random() useful sometimes?
+ * - Which system algorithms are available, maybe name them after real
+ *   algorithm by compile-time detection?
+ * - Get this to compile :-)
+ */
 #ifndef PHP_RAND_H
 #define	PHP_RAND_H
 
 #include <stdlib.h>
 
-#ifndef RAND_MAX
-#define RAND_MAX (1<<15)
-#endif
-
-#if HAVE_LRAND48
-#define PHP_RAND_MAX 2147483647
-#else
-#define PHP_RAND_MAX RAND_MAX
-#endif
-
-/* Define rand Function wrapper */
-#ifdef HAVE_RANDOM
-#define php_rand() random()
-#else
-#ifdef HAVE_LRAND48
-#define php_rand() lrand48()
-#else
-#define php_rand() rand()
-#endif
-#endif
-
-/* Define srand Function wrapper */
-#ifdef HAVE_SRANDOM
-#define php_srand(seed) srandom((unsigned int)seed)
-#else
-#ifdef HAVE_SRAND48
-#define php_srand(seed) srand48((long)seed)
-#else
-#define php_srand(seed) srand((unsigned int)seed)
-#endif
-#endif
+/* FIXME: that '_php_randgen_entry' needed, or not? */
+typedef struct _php_randgen_entry {
+	void (*srand)(long seed);
+	long (*rand)(void);
+	long randmax;
+	char *ini_str;
+} php_randgen_entry;
+
+/* an ARRAY of POINTERS, not vice versa */
+extern php_randgen_entry *php_randgen_entries[];
+
+#define PHP_RANDGEN_ENTRY(which, nsrand, nrand, nrandmax, nini_str) { \
+	php_randgen_entries[which] = emalloc(sizeof(php_randgen_entry)); \
+	php_randgen_entries[which]->srand	= nsrand;	\
+	php_randgen_entries[which]->rand	= nrand;	\
+	php_randgen_entries[which]->randmax	= nrandmax;	\
+	php_randgen_entries[which]->ini_str	= nini_str;	\
+}
+
+/* Define random generator constants */
+#define PHP_RAND_SYS		0
+#define PHP_RAND_LRAND48	1
+#define PHP_RAND_MT			2
+#define PHP_RAND_LCG		3
+
+#define PHP_RAND_DEFAULT	PHP_RAND_MT
+
+/* how many there are */
+#define PHP_RAND_NUMRANDS	4
+
+/* Proto's */
+PHP_FUNCTION(srand);
+PHP_FUNCTION(rand);
+PHP_FUNCTION(getrandmax);
+PHP_FUNCTION(mt_srand);
+PHP_FUNCTION(mt_rand);
+PHP_FUNCTION(mt_getrandmax);
+
+PHPAPI long   php_rand(void);
+PHPAPI long   php_rand_range(long min, long max);
+PHPAPI double php_drand(void);
+PHPAPI long   php_randmax(void);
 
 #endif	/* PHP_RAND_H */
+
+/*
+ * Local variables:
+ * tab-width: 4
+ * c-basic-offset: 4
+ * End:
+ * vim600: fdm=marker
+ * vim: sw=4 ts=4 tw=78
+ */