summary refs log tree commit diff
path: root/nis/nis_hash.c
diff options
context:
space:
mode:
authorUlrich Drepper <drepper@redhat.com>2004-09-08 15:46:42 +0000
committerUlrich Drepper <drepper@redhat.com>2004-09-08 15:46:42 +0000
commitc207f23b0b6b2d215be65e670d453768ad304247 (patch)
tree5d10943ec51bbda849db9ca2fdcc7b43feb2011c /nis/nis_hash.c
parent0a3ad40da92c0036bd3bd87949f7d7d9864c31c7 (diff)
downloadglibc-c207f23b0b6b2d215be65e670d453768ad304247.tar.gz
glibc-c207f23b0b6b2d215be65e670d453768ad304247.tar.xz
glibc-c207f23b0b6b2d215be65e670d453768ad304247.zip
Update.
	* nscd/connections.c: Implement r/o sharing of nscd's cache with client
	processes via shared memory.
	* nscd/nscd-client.h: Likewise.
	* nscd/nscd.h: Likewise.
	* nscd/nscd_conf.c: Likewise.
	* nscd/nscd_getgr_r.c: Likewise.
	* nscd/nscd_getpw_r.c: Likewise.
	* nscd/nscd_gethst_r.c: Likewise.
	* nscd/nscd.conf: Add new config parameters.
	* nscd/Makefile (aux): Add nscd_helper.
	* nscd/nscd_helper.c: New file.
	* nscd/mem.c (gc): Indicate beginning and end of the gc cycle.

	* nscd/hstcache.c: Simplify a lot.  We cache only the request itself,
	no derived information.
	* connections.c (nscd_init): Fix bug in testing size of the persistent.

	* nis/Makefile (aux): Add nis_hash.
	* nis/nis_hash.c: New file.  Split out from nis_util.c.
	* nis/nis_util.c: Move __nis_hash code in separate file.

	* csu/tst-atomic.c: Improve atomic_increment_val test which would
	not have found a ppc bug.
Diffstat (limited to 'nis/nis_hash.c')
-rw-r--r--nis/nis_hash.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/nis/nis_hash.c b/nis/nis_hash.c
new file mode 100644
index 0000000000..ddd91515b0
--- /dev/null
+++ b/nis/nis_hash.c
@@ -0,0 +1,76 @@
+/* Copyright (c) 1997, 1998, 1999, 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Thorsten Kukuk <kukuk@suse.de>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <rpcsvc/nis.h>
+
+/* This is from libc/db/hash/hash_func.c, hash3 is static there */
+/*
+ * This is INCREDIBLY ugly, but fast.  We break the string up into 8 byte
+ * units.  On the first time through the loop we get the "leftover bytes"
+ * (strlen % 8).  On every other iteration, we perform 8 HASHC's so we handle
+ * all 8 bytes.  Essentially, this saves us 7 cmp & branch instructions.  If
+ * this routine is heavily used enough, it's worth the ugly coding.
+ *
+ * OZ's original sdbm hash
+ */
+uint32_t
+__nis_hash (const void *keyarg, register size_t len)
+{
+  register const u_char *key;
+  register size_t loop;
+  register uint32_t h;
+
+#define HASHC   h = *key++ + 65599 * h
+
+  h = 0;
+  key = keyarg;
+  if (len > 0)
+    {
+      loop = (len + 8 - 1) >> 3;
+      switch (len & (8 - 1))
+	{
+	case 0:
+	  do {
+	    HASHC;
+	    /* FALLTHROUGH */
+	  case 7:
+	    HASHC;
+	    /* FALLTHROUGH */
+	  case 6:
+	    HASHC;
+	    /* FALLTHROUGH */
+	  case 5:
+	    HASHC;
+	    /* FALLTHROUGH */
+	  case 4:
+	    HASHC;
+	    /* FALLTHROUGH */
+	  case 3:
+	    HASHC;
+	    /* FALLTHROUGH */
+	  case 2:
+	    HASHC;
+	    /* FALLTHROUGH */
+	  case 1:
+	    HASHC;
+	  } while (--loop);
+	}
+    }
+  return h;
+}