diff options
Diffstat (limited to 'lib/hash-triple.c')
-rw-r--r-- | lib/hash-triple.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/lib/hash-triple.c b/lib/hash-triple.c new file mode 100644 index 0000000..560e442 --- /dev/null +++ b/lib/hash-triple.c @@ -0,0 +1,77 @@ +/* Hash functions for file-related triples: name, device, inode. + Copyright (C) 2007, 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 <https://www.gnu.org/licenses/>. */ + +/* written by Jim Meyering */ + +#include <config.h> + +#include "hash-triple.h" + +#include <stdlib.h> +#include <string.h> + +#include "hash-pjw.h" +#include "same.h" +#include "same-inode.h" + +#define STREQ(a, b) (strcmp (a, b) == 0) + +/* Hash an F_triple, and *do* consider the file name. */ +size_t +triple_hash (void const *x, size_t table_size) +{ + struct F_triple const *p = x; + size_t tmp = hash_pjw (p->name, table_size); + + /* Ignoring the device number here should be fine. */ + return (tmp ^ p->st_ino) % table_size; +} + +/* Hash an F_triple, without considering the file name. */ +size_t +triple_hash_no_name (void const *x, size_t table_size) +{ + struct F_triple const *p = x; + + /* Ignoring the device number here should be fine. */ + return p->st_ino % table_size; +} + +/* Compare two F_triple structs. */ +bool +triple_compare (void const *x, void const *y) +{ + struct F_triple const *a = x; + struct F_triple const *b = y; + return (SAME_INODE (*a, *b) && same_name (a->name, b->name)) ? true : false; +} + +bool +triple_compare_ino_str (void const *x, void const *y) +{ + struct F_triple const *a = x; + struct F_triple const *b = y; + return (SAME_INODE (*a, *b) && STREQ (a->name, b->name)) ? true : false; +} + +/* Free an F_triple. */ +void +triple_free (void *x) +{ + struct F_triple *a = x; + free (a->name); + free (a); +} |