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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 0000000..3e0b8b2
--- /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;
+}