Initial revision

1 files changed, 144 insertions, 0 deletions

diff --git a/libidu/hash.h b/libidu/hash.h
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+/* hash.h -- decls for hash table
+   Copyright (C) 1995 Free Software Foundation, Inc.
+   Written by Greg McGary <gkm@gnu.ai.mit.edu>
+
+   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 2, 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, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+#ifndef _hash_h_
+#define _hash_h_
+
+#include <stdio.h>
+
+typedef unsigned long (*hash_func_t) __P((void const *key));
+typedef int (*hash_cmp_func_t) __P((void const *x, void const *y));
+typedef void (*hash_map_func_t) __P((void const *item));
+
+struct hash_table
+{
+  void **ht_vec;
+  unsigned long ht_size;	/* total number of slots (power of 2) */
+  unsigned long ht_capacity;	/* usable slots, limited by loading-factor */
+  unsigned long ht_fill;	/* items in table */
+  unsigned long ht_collisions;	/* # of failed calls to comparison function */
+  unsigned long ht_lookups;	/* # of queries */
+  unsigned int ht_rehashes;	/* # of times we've expanded table */
+  hash_func_t ht_hash_1;	/* primary hash function */
+  hash_func_t ht_hash_2;	/* secondary hash function */
+  hash_cmp_func_t ht_compare;	/* comparison function */
+};
+
+typedef int (*qsort_cmp_t) __P((void const *, void const *));
+
+void hash_init __P((struct hash_table *ht, unsigned long size,
+		    hash_func_t hash_1, hash_func_t hash_2, hash_cmp_func_t hash_cmp));
+void hash_load __P((struct hash_table *ht, void *item_table,
+		    unsigned long cardinality, unsigned long size));
+void **hash_find_slot __P((struct hash_table *ht, void const *key));
+void *hash_find_item __P((struct hash_table *ht, void const *key));
+void *hash_insert __P((struct hash_table *ht, void *item));
+void *hash_insert_at __P((struct hash_table *ht, void *item, void const *slot));
+void *hash_delete __P((struct hash_table *ht, void const *item));
+void *hash_delete_at __P((struct hash_table *ht, void const *slot));
+void hash_delete_items __P((struct hash_table *ht));
+void hash_free_items __P((struct hash_table *ht));
+void hash_free __P((struct hash_table *ht, int free_items));
+void hash_map __P((struct hash_table *ht, hash_map_func_t map));
+void hash_print_stats __P((struct hash_table *ht, FILE *out_FILE));
+void **hash_dump __P((struct hash_table *ht, void **vector_0, qsort_cmp_t compare));
+
+extern void *hash_deleted_item;
+#define HASH_VACANT(item) ((item) == 0 || (void *) (item) == hash_deleted_item)
+
+
+/* hash and comparison macros for string keys. */
+
+#define STRING_HASH_1(_key_, _result_) { \
+  unsigned char const *kk = (unsigned char const *) (_key_) - 1; \
+  while (*++kk) \
+    (_result_) += (*kk << (kk[1] & 0xf)); \
+} while (0)
+#define return_STRING_HASH_1(_key_) do { \
+  unsigned long result = 0; \
+  STRING_HASH_1 ((_key_), result); \
+  return result; \
+} while (0)
+
+#define STRING_HASH_2(_key_, _result_) do { \
+  unsigned char const *kk = (unsigned char const *) (_key_) - 1; \
+  while (*++kk) \
+    (_result_) += (*kk << (kk[1] & 0x7)); \
+} while (0)
+#define return_STRING_HASH_2(_key_) do { \
+  unsigned long result = 0; \
+  STRING_HASH_2 ((_key_), result); \
+  return result; \
+} while (0)
+
+#define STRING_COMPARE(_x_, _y_, _result_) do { \
+  unsigned char const *xx = (unsigned char const *) (_x_) - 1; \
+  unsigned char const *yy = (unsigned char const *) (_y_) - 1; \
+  do { \
+    if (*++xx == '\0') { \
+      yy++; \
+      break; \
+    } \
+  } while (*xx == *++yy); \
+  (_result_) = *xx - *yy; \
+} while (0)
+#define return_STRING_COMPARE(_x_, _y_) do { \
+  int result; \
+  STRING_COMPARE (_x_, _y_, result); \
+  return result; \
+} while (0)
+
+/* hash and comparison macros for integer keys. */
+
+#define INTEGER_HASH_1(_key_, _result_) do { \
+  (_result_) += ((unsigned long)(_key_)); \
+} while (0)
+#define return_INTEGER_HASH_1(_key_) do { \
+  unsigned long result = 0; \
+  INTEGER_HASH_1 ((_key_), result); \
+  return result; \
+} while (0)
+
+#define INTEGER_HASH_2(_key_, _result_) do { \
+  (_result_) += ~((unsigned long)(_key_)); \
+} while (0)
+#define return_INTEGER_HASH_2(_key_) do { \
+  unsigned long result = 0; \
+  INTEGER_HASH_2 ((_key_), result); \
+  return result; \
+} while (0)
+
+#define INTEGER_COMPARE(_x_, _y_, _result_) do { \
+  (_result_) = _x_ - _y_; \
+} while (0)
+#define return_INTEGER_COMPARE(_x_, _y_) do { \
+  int result; \
+  INTEGER_COMPARE (_x_, _y_, result); \
+  return result; \
+} while (0)
+
+/* hash and comparison macros for address keys. */
+
+#define ADDRESS_HASH_1(_key_, _result_) INTEGER_HASH_1 (((unsigned long)(_key_)) >> 3, (_result_))
+#define ADDRESS_HASH_2(_key_, _result_) INTEGER_HASH_2 (((unsigned long)(_key_)) >> 3, (_result_))
+#define ADDRESS_COMPARE(_x_, _y_, _result_) INTEGER_COMPARE ((_x_), (_y_), (_result_))
+#define return_ADDRESS_HASH_1(_key_) return_INTEGER_HASH_1 (((unsigned long)(_key_)) >> 3)
+#define return_ADDRESS_HASH_2(_key_) return_INTEGER_HASH_2 (((unsigned long)(_key_)) >> 3)
+#define return_ADDRESS_COMPARE(_x_, _y_) return_INTEGER_COMPARE ((_x_), (_y_))
+
+#endif /* not _hash_h_ */