From 46a43a99c6b835dd6f10e2fd4d24cd5c70a26691 Mon Sep 17 00:00:00 2001
From: Jeff Johnston <jjohnstn@redhat.com>
Date: Fri, 9 Jun 2000 18:50:05 +0000
Subject: [PATCH] Fri Jun 9 14:28:00 2000 Jeff Johnston
<jjohnstn@cygnus.com>
* libc/include/sys/reent.h (_rand_next): Changed to
unsigned long long and moved to end of _reent struct in _new union.
(_REENT_INIT): Changed to move _rand_next initialization.
* libc/stdlib/rand.c (rand): Changed to use unsigned long long
linear congruential algorithm that is used by DJGPP.
---
newlib/ChangeLog | 8 ++++++++
newlib/libc/include/sys/reent.h | 8 +++++---
newlib/libc/stdlib/rand.c | 9 ++++++---
3 files changed, 19 insertions(+), 6 deletions(-)
diff --git a/newlib/ChangeLog b/newlib/ChangeLog
index a322e1143..9ec544c40 100644
--- a/newlib/ChangeLog
+++ b/newlib/ChangeLog
@@ -1,3 +1,11 @@
+Fri Jun 9 14:28:00 2000 Jeff Johnston <jjohnstn@cygnus.com>
+
+ * libc/include/sys/reent.h (_rand_next): Changed to
+ unsigned long long and moved to end of _reent struct in _new union.
+ (_REENT_INIT): Changed to move _rand_next initialization.
+ * libc/stdlib/rand.c (rand): Changed to use unsigned long long
+ linear congruential algorithm that is used by DJGPP.
+
Thu Jun 8 21:18:00 2000 Ranjith Kumaran <ranjith@cygnus.com>
* libc/include/stdlib.h: Set RAND_MAX to __RAND_MAX.
diff --git a/newlib/libc/include/sys/reent.h b/newlib/libc/include/sys/reent.h
index 110493675..d6aefed6e 100644
--- a/newlib/libc/include/sys/reent.h
+++ b/newlib/libc/include/sys/reent.h
@@ -177,11 +177,13 @@ struct _reent
{
struct
{
- unsigned int _rand_next;
+ unsigned int _unused_rand;
char * _strtok_last;
char _asctime_buf[26];
struct tm _localtime_buf;
int _gamma_signgam;
+ unsigned long long _rand_next;
+
} _reent;
/* Two next two fields were once used by malloc. They are no longer
used. They are used to preserve the space used before so as to
@@ -210,8 +212,8 @@ struct _reent
#define _REENT_INIT(var) \
{ 0, &var.__sf[0], &var.__sf[1], &var.__sf[2], 0, "", 0, "C", \
- 0, NULL, NULL, 0, NULL, NULL, 0, NULL, { {1, NULL, "", \
- { 0,0,0,0,0,0,0,0}, 0 } } }
+ 0, NULL, NULL, 0, NULL, NULL, 0, NULL, { {0, NULL, "", \
+ { 0,0,0,0,0,0,0,0}, 0, 1} } }
/*
* All references to struct _reent are via this pointer.
diff --git a/newlib/libc/stdlib/rand.c b/newlib/libc/stdlib/rand.c
index 3d739efbc..4cf7f2932 100644
--- a/newlib/libc/stdlib/rand.c
+++ b/newlib/libc/stdlib/rand.c
@@ -78,9 +78,12 @@ _DEFUN (srand, (seed), unsigned int seed)
int
_DEFUN_VOID (rand)
{
- return ((_REENT->_new._reent._rand_next =
- _REENT->_new._reent._rand_next * 1103515245 + 12345 )
- & RAND_MAX );
+ /* This multiplier was obtained from Knuth, D.E., "The Art of
+ Computer Programming," Vol 2, Seminumerical Algorithms, Third
+ Edition, Addison-Wesley, 1998, p. 106 (line 26) & p. 108 */
+ _REENT->_new._reent._rand_next =
+ _REENT->_new._reent._rand_next * 6364136223846793005LL + 1;
+ return (int)((_REENT->_new._reent._rand_next >> 32) & RAND_MAX);
}
#endif /* _REENT_ONLY */