From 74b60c5712f2a84904b95d008953c140a9bd5dd2 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:49:50 +0200 Subject: Adding upstream version 2.9.4. Signed-off-by: Daniel Baumann --- gl/lib/hash-pjw.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 gl/lib/hash-pjw.c (limited to 'gl/lib/hash-pjw.c') diff --git a/gl/lib/hash-pjw.c b/gl/lib/hash-pjw.c new file mode 100644 index 0000000..f9bedab --- /dev/null +++ b/gl/lib/hash-pjw.c @@ -0,0 +1,40 @@ +/* hash-pjw.c -- compute a hash value from a NUL-terminated string. + + Copyright (C) 2001, 2003, 2006, 2009-2020 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +#include + +#include "hash-pjw.h" + +#include + +#define SIZE_BITS (sizeof (size_t) * CHAR_BIT) + +/* A hash function for NUL-terminated char* strings using + the method described by Bruno Haible. + See https://www.haible.de/bruno/hashfunc.html. */ + +size_t +hash_pjw (const void *x, size_t tablesize) +{ + const char *s; + size_t h = 0; + + for (s = x; *s; s++) + h = *s + ((h << 9) | (h >> (SIZE_BITS - 9))); + + return h % tablesize; +} -- cgit v1.2.3