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-rw-r--r--lib/hash-triple.c77
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diff --git a/lib/hash-triple.c b/lib/hash-triple.c
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+/* 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);
+}