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authorUlrich Drepper <drepper@redhat.com>1996-12-07 03:30:25 +0000
committerUlrich Drepper <drepper@redhat.com>1996-12-07 03:30:25 +0000
commita18f587da5a0a91bcd1307ed0f122ca2ce994c15 (patch)
tree174cca5dd1f842dff255d6491ff6677ac7772eab /stdlib/rand_r.c
parent6b612c67093292a99a336fae38e459ee00927d0f (diff)
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update from main archive 961206
Sat Dec  7 03:24:36 1996  Ulrich Drepper  <drepper@cygnus.com>

	* configure.in: Discard error message from test in test for
	bash-2.0.

	* io/getpw.c: Don't apply getcwd on user supplied buffer.
	Instead always use temporary buffer and only copy the result.
	Patch by HJ Lu.
	* stdlib/canonicalize.c: Likewise.

	* libio/fileops.c: Change comments according to libg++2.8b5.
	* libio/iosetvbuf.c: Follow change in libg++-2.8b5 to clear
	unbuffered flag.
	Reported by HJ Lu.

	* manual/nss.texi: Correct prototypes.

	* misc/syslog.c: Make reentrant.  Catch SIGPIPE signal to prevent
	crash if syslog daemon is restarted.

	* stdlib/rand_r.c: New file.  Implementation of POSIX.2 function
	rand_r.
	* stdlib/Makefile (routines): Add rand_r.

	* sysdeps/stub/libc-lock.h: Define __libc_lock_trylock and
	__libc_mutex_lock.

	* configure.in: Add --disable-sanity-check option.
	* sysdeps/unix/sysv/linux/configure.in: If linuxthreads or
	des-crypt are not available and --disbale-sanity-check is not
	given abort with a message.

Thu Dec  5 19:19:53 1996  Richard Henderson  <rth@tamu.edu>

	* posix/glob.c: Tests against STDC_HEADERS should also test
	__GNU_LIBRARY__.

Thu Dec  5 16:20:55 1996  Ulrich Drepper  <drepper@cygnus.com>

	* misc/err.c (vwarn): Set errno again before using %m format.

Thu Dec  5 10:14:05 1996  Andreas Jaeger  <aj@arthur.pfalz.de>

	* grp/grp.h: Add declaration of __getgrent_r.

	* io/fts.c (fts_build): Remove "register" from variables dirbuf
	and dp since their address is needed.

	* sysdeps/posix/getcwd.c (__getcwd): Remove "register" from
	variable d since d's address is needed.

	* misc/tst-dirname.c (main): Provide prototype.
	* misc/ioctltst.c (main): Dito.

	* Makefile: Add gnu/lib-names.h to install-others before including
	Makerules.

Wed Dec  4 16:00:09 1996  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/unix/sysv/linux/sys/socketvar.h: New file.  Simply use
	<sys/socket.h>.
	* sysdeps/unix/sysv/linux/Dist: Add sys/socketvar.h.
	* sysdeps/unix/sysv/linux/Makefile [$(subdir)=inet)]: Add
	sys/socketvar.h to sysdep_headers.

	since the value might be outside the range of the `long int'.
Diffstat (limited to 'stdlib/rand_r.c')
-rw-r--r--stdlib/rand_r.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/stdlib/rand_r.c b/stdlib/rand_r.c
new file mode 100644
index 0000000000..3e0b8b2bc0
--- /dev/null
+++ b/stdlib/rand_r.c
@@ -0,0 +1,49 @@
+/* Reentrant random function frm POSIX.1c.
+   Copyright (C) 1996 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <stdlib.h>
+
+
+/* This algorithm is mentioned in the ISO C standard, here extended
+   for 32 bits.  */
+int
+rand_r (unsigned int *seed)
+{
+  unsigned int next = *seed;
+  int result;
+
+  next *= 1103515245;
+  next += 12345;
+  result = (unsigned int) (next / 65536) % 2048;
+
+  next *= 1103515245;
+  next += 12345;
+  result <<= 11;
+  result ^= (unsigned int) (next / 65536) % 1024;
+
+  next *= 1103515245;
+  next += 12345;
+  result <<= 10;
+  result ^= (unsigned int) (next / 65536) % 1024;
+
+  *seed = next;
+
+  return result;
+}