149 lines
3.2 KiB
C
149 lines
3.2 KiB
C
/*
|
|
* Copyright (C) 2003-2011 The Music Player Daemon Project
|
|
* http://www.musicpd.org
|
|
*
|
|
* 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 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, write to the Free Software Foundation, Inc.,
|
|
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*/
|
|
|
|
#include "config.h"
|
|
#include "strset.h"
|
|
|
|
#include <assert.h>
|
|
#include <string.h>
|
|
#include <stdlib.h>
|
|
|
|
#define NUM_SLOTS 16384
|
|
|
|
struct strset_slot {
|
|
struct strset_slot *next;
|
|
const char *value;
|
|
};
|
|
|
|
struct strset {
|
|
unsigned size;
|
|
|
|
struct strset_slot *current_slot;
|
|
unsigned next_slot;
|
|
|
|
struct strset_slot slots[NUM_SLOTS];
|
|
};
|
|
|
|
static unsigned calc_hash(const char *p) {
|
|
unsigned hash = 5381;
|
|
|
|
assert(p != NULL);
|
|
|
|
while (*p != 0)
|
|
hash = (hash << 5) + hash + *p++;
|
|
|
|
return hash;
|
|
}
|
|
|
|
G_GNUC_MALLOC struct strset *strset_new(void)
|
|
{
|
|
struct strset *set = g_new0(struct strset, 1);
|
|
return set;
|
|
}
|
|
|
|
void strset_free(struct strset *set)
|
|
{
|
|
unsigned i;
|
|
|
|
for (i = 0; i < NUM_SLOTS; ++i) {
|
|
struct strset_slot *slot = set->slots[i].next, *next;
|
|
|
|
while (slot != NULL) {
|
|
next = slot->next;
|
|
g_free(slot);
|
|
slot = next;
|
|
}
|
|
}
|
|
|
|
g_free(set);
|
|
}
|
|
|
|
void strset_add(struct strset *set, const char *value)
|
|
{
|
|
struct strset_slot *base_slot
|
|
= &set->slots[calc_hash(value) % NUM_SLOTS];
|
|
struct strset_slot *slot = base_slot;
|
|
|
|
if (base_slot->value == NULL) {
|
|
/* empty slot - put into base_slot */
|
|
assert(base_slot->next == NULL);
|
|
|
|
base_slot->value = value;
|
|
++set->size;
|
|
return;
|
|
}
|
|
|
|
for (slot = base_slot; slot != NULL; slot = slot->next)
|
|
if (strcmp(slot->value, value) == 0)
|
|
/* found it - do nothing */
|
|
return;
|
|
|
|
/* insert it into the slot chain */
|
|
slot = g_new(struct strset_slot, 1);
|
|
slot->next = base_slot->next;
|
|
slot->value = value;
|
|
base_slot->next = slot;
|
|
++set->size;
|
|
}
|
|
|
|
int strset_get(const struct strset *set, const char *value)
|
|
{
|
|
const struct strset_slot *slot = &set->slots[calc_hash(value)];
|
|
|
|
if (slot->value == NULL)
|
|
return 0;
|
|
|
|
for (slot = slot->next; slot != NULL; slot = slot->next)
|
|
if (strcmp(slot->value, value) == 0)
|
|
/* found it - do nothing */
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
unsigned strset_size(const struct strset *set)
|
|
{
|
|
return set->size;
|
|
}
|
|
|
|
void strset_rewind(struct strset *set)
|
|
{
|
|
set->current_slot = NULL;
|
|
set->next_slot = 0;
|
|
}
|
|
|
|
const char *strset_next(struct strset *set)
|
|
{
|
|
if (set->current_slot != NULL && set->current_slot->next != NULL) {
|
|
set->current_slot = set->current_slot->next;
|
|
return set->current_slot->value;
|
|
}
|
|
|
|
while (set->next_slot < NUM_SLOTS &&
|
|
set->slots[set->next_slot].value == NULL)
|
|
++set->next_slot;
|
|
|
|
if (set->next_slot >= NUM_SLOTS)
|
|
return NULL;
|
|
|
|
set->current_slot = &set->slots[set->next_slot++];
|
|
return set->current_slot->value;
|
|
}
|
|
|