ZeroTierOne/attic/historic/anode/libanode/impl/dictionary.h
2017-05-04 10:42:22 -07:00

127 lines
3.6 KiB
C

/* libanode: the Anode C reference implementation
* Copyright (C) 2009-2010 Adam Ierymenko <adam.ierymenko@gmail.com>
*
* 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 <http://www.gnu.org/licenses/>. */
/* This is a simple string hash table suitable for small tables such as zone
* files or HTTP header lists. */
#ifndef _ANODE_DICTIONARY_H
#define _ANODE_DICTIONARY_H
#include "misc.h"
/* This is a fixed hash table and is designed for relatively small numbers
* of keys for things like zone files. */
#define ANODE_DICTIONARY_FIXED_HASH_TABLE_SIZE 16
#define ANODE_DICTIONARY_FIXED_HASH_TABLE_MASK 15
/* Computes a hash code for a string and returns the hash bucket */
static inline unsigned int AnodeDictionary__get_bucket(const char *s)
{
unsigned int hc = 3;
while (*s)
hc = ((hc << 4) + hc) + (unsigned int)*(s++);
return ((hc ^ (hc >> 4)) & ANODE_DICTIONARY_FIXED_HASH_TABLE_MASK);
}
/* Case insensitive version of get_bucket */
static inline unsigned int AnodeDictionary__get_bucket_ci(const char *s)
{
unsigned int hc = 3;
while (*s)
hc = ((hc << 4) + hc) + (unsigned int)Anode_tolower(*(s++));
return ((hc ^ (hc >> 4)) & ANODE_DICTIONARY_FIXED_HASH_TABLE_MASK);
}
struct AnodeDictionaryEntry
{
char *key;
char *value;
struct AnodeDictionaryEntry *next;
};
struct AnodeDictionary
{
struct AnodeDictionaryEntry *ht[ANODE_DICTIONARY_FIXED_HASH_TABLE_SIZE];
unsigned int size;
int case_sensitive;
};
static inline void AnodeDictionary_init(struct AnodeDictionary *d,int case_sensitive)
{
Anode_zero((void *)d,sizeof(struct AnodeDictionary));
d->case_sensitive = case_sensitive;
}
void AnodeDictionary_clear(struct AnodeDictionary *d);
static inline void AnodeDictionary_destroy(struct AnodeDictionary *d)
{
AnodeDictionary_clear(d);
}
void AnodeDictionary_put(struct AnodeDictionary *d,const char *key,const char *value);
static inline const char *AnodeDictionary_get(struct AnodeDictionary *d,const char *key)
{
struct AnodeDictionaryEntry *e;
unsigned int bucket = (d->case_sensitive) ? AnodeDictionary__get_bucket(key) : AnodeDictionary__get_bucket_ci(key);
e = d->ht[bucket];
while (e) {
if ((d->case_sensitive ? Anode_streq(key,e->key) : Anode_strcaseeq(key,e->key)))
return e->value;
e = e->next;
}
return (const char *)0;
}
static inline void AnodeDictionary_iterate(
struct AnodeDictionary *d,
void *arg,
int (*func)(void *,const char *,const char *))
{
struct AnodeDictionaryEntry *e;
unsigned int bucket;
for(bucket=0;bucket<ANODE_DICTIONARY_FIXED_HASH_TABLE_SIZE;++bucket) {
e = d->ht[bucket];
while (e) {
if (!func(arg,e->key,e->value))
return;
e = e->next;
}
}
}
void AnodeDictionary_read(
struct AnodeDictionary *d,
char *in,
const char *line_breaks,
const char *kv_breaks,
const char *comment_chars,
char escape_char,
int trim_whitespace_from_keys,
int trim_whitespace_from_values);
long AnodeDictionary_write(
struct AnodeDictionary *d,
char *out,
long out_size,
const char *line_break,
const char *kv_break);
#endif