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author | Derrell Lipman <derrell@samba.org> | 2006-09-23 19:15:27 +0000 |
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committer | Gerald (Jerry) Carter <jerry@samba.org> | 2007-10-10 14:20:15 -0500 |
commit | 4d1a4e8e7ce047f70113d9fa52f7961c0fee6557 (patch) | |
tree | bd1bce916dba4c725700af4a8a2a790c7b0c2ccb /source4/lib/json/linkhash.c | |
parent | 333557e28fc1c1934756b96f08711e050568926f (diff) | |
download | samba-4d1a4e8e7ce047f70113d9fa52f7961c0fee6557.tar.gz samba-4d1a4e8e7ce047f70113d9fa52f7961c0fee6557.tar.bz2 samba-4d1a4e8e7ce047f70113d9fa52f7961c0fee6557.zip |
r18848: Save the json library before I start hacking on it. I'm going to be
converting it to natively use ejs objects, instead of its own internal
format.
(This used to be commit 119db8924a6e9c40a94c76c57198877875c53afc)
Diffstat (limited to 'source4/lib/json/linkhash.c')
-rw-r--r-- | source4/lib/json/linkhash.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/source4/lib/json/linkhash.c b/source4/lib/json/linkhash.c new file mode 100644 index 0000000000..6cfc9a0ea6 --- /dev/null +++ b/source4/lib/json/linkhash.c @@ -0,0 +1,217 @@ +/* + * $Id: linkhash.c,v 1.4 2006/01/26 02:16:28 mclark Exp $ + * + * Copyright (c) 2004, 2005 Metaparadigm Pte. Ltd. + * Michael Clark <michael@metaparadigm.com> + * + * This library is free software; you can redistribute it and/or modify + * it under the terms of the MIT license. See COPYING for details. + * + */ + +#include "config.h" + +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <stdarg.h> +#include <stddef.h> +#include <limits.h> + +#include "linkhash.h" + +void lh_abort(const char *msg, ...) +{ + va_list ap; + va_start(ap, msg); + vprintf(msg, ap); + exit(1); +} + +unsigned long lh_ptr_hash(void *k) +{ + /* CAW: refactored to be 64bit nice */ + return (unsigned long)((((ptrdiff_t)k * LH_PRIME) >> 4) & ULONG_MAX); +} + +int lh_ptr_equal(void *k1, void *k2) +{ + return (k1 == k2); +} + +unsigned long lh_char_hash(void *k) +{ + unsigned int h = 0; + const char* data = k; + + while( *data!=0 ) h = h*129 + (unsigned int)(*data++) + LH_PRIME; + + return h; +} + +int lh_char_equal(void *k1, void *k2) +{ + return (strcmp((char*)k1, (char*)k2) == 0); +} + +struct lh_table* lh_table_new(int size, char *name, + lh_entry_free_fn *free_fn, + lh_hash_fn *hash_fn, + lh_equal_fn *equal_fn) +{ + int i; + struct lh_table *t; + + t = calloc(1, sizeof(struct lh_table)); + if(!t) lh_abort("lh_table_new: calloc failed\n"); + t->count = 0; + t->size = size; + t->name = name; + t->table = calloc(size, sizeof(struct lh_entry)); + if(!t->table) lh_abort("lh_table_new: calloc failed\n"); + t->free_fn = free_fn; + t->hash_fn = hash_fn; + t->equal_fn = equal_fn; + for(i = 0; i < size; i++) t->table[i].k = LH_EMPTY; + return t; +} + +struct lh_table* lh_kchar_table_new(int size, char *name, + lh_entry_free_fn *free_fn) +{ + return lh_table_new(size, name, free_fn, lh_char_hash, lh_char_equal); +} + +struct lh_table* lh_kptr_table_new(int size, char *name, + lh_entry_free_fn *free_fn) +{ + return lh_table_new(size, name, free_fn, lh_ptr_hash, lh_ptr_equal); +} + +void lh_table_resize(struct lh_table *t, int new_size) +{ + struct lh_table *new_t; + struct lh_entry *ent; + + new_t = lh_table_new(new_size, t->name, NULL, t->hash_fn, t->equal_fn); + ent = t->head; + while(ent) { + lh_table_insert(new_t, ent->k, ent->v); + ent = ent->next; + } + free(t->table); + t->table = new_t->table; + t->size = new_size; + t->head = new_t->head; + t->tail = new_t->tail; + t->resizes++; + free(new_t); +} + +void lh_table_free(struct lh_table *t) +{ + struct lh_entry *c; + for(c = t->head; c != NULL; c = c->next) { + if(t->free_fn) { + t->free_fn(c); + } + } + free(t->table); + free(t); +} + + +int lh_table_insert(struct lh_table *t, void *k, void *v) +{ + unsigned long h, n; + + t->inserts++; + if(t->count > t->size * 0.66) lh_table_resize(t, t->size * 2); + + h = t->hash_fn(k); + n = h % t->size; + + while( 1 ) { + if(t->table[n].k == LH_EMPTY || t->table[n].k == LH_FREED) break; + t->collisions++; + if(++n == t->size) n = 0; + } + + t->table[n].k = k; + t->table[n].v = v; + t->count++; + + if(t->head == NULL) { + t->head = t->tail = &t->table[n]; + t->table[n].next = t->table[n].prev = NULL; + } else { + t->tail->next = &t->table[n]; + t->table[n].prev = t->tail; + t->table[n].next = NULL; + t->tail = &t->table[n]; + } + + return 0; +} + + +struct lh_entry* lh_table_lookup_entry(struct lh_table *t, void *k) +{ + unsigned long h = t->hash_fn(k); + unsigned long n = h % t->size; + + t->lookups++; + while( 1 ) { + if(t->table[n].k == LH_EMPTY) return NULL; + if(t->table[n].k != LH_FREED && + t->equal_fn(t->table[n].k, k)) return &t->table[n]; + if(++n == t->size) n = 0; + } + return NULL; +} + + +void* lh_table_lookup(struct lh_table *t, void *k) +{ + struct lh_entry *e = lh_table_lookup_entry(t, k); + if(e) return e->v; + return NULL; +} + + +int lh_table_delete_entry(struct lh_table *t, struct lh_entry *e) +{ + ptrdiff_t n = (ptrdiff_t)(e - t->table); /* CAW: fixed to be 64bit nice, still need the crazy negative case... */ + + /* CAW: this is bad, really bad, maybe stack goes other direction on this machine... */ + if(n < 0) { return -2; } + + if(t->table[n].k == LH_EMPTY || t->table[n].k == LH_FREED) return -1; + t->count--; + if(t->free_fn) t->free_fn(e); + t->table[n].v = NULL; + t->table[n].k = LH_FREED; + if(t->tail == &t->table[n] && t->head == &t->table[n]) { + t->head = t->tail = NULL; + } else if (t->head == &t->table[n]) { + t->head->next->prev = NULL; + t->head = t->head->next; + } else if (t->tail == &t->table[n]) { + t->tail->prev->next = NULL; + t->tail = t->tail->prev; + } else { + t->table[n].prev->next = t->table[n].next; + t->table[n].next->prev = t->table[n].prev; + } + t->table[n].next = t->table[n].prev = NULL; + return 0; +} + + +int lh_table_delete(struct lh_table *t, void *k) +{ + struct lh_entry *e = lh_table_lookup_entry(t, k); + if(!e) return -1; + return lh_table_delete_entry(t, e); +} + |