Show fifo.c syntax highlighted
/*
* $Id: fifo.c 11437 2006-08-05 00:24:20Z cbiere $
*
* Copyright (c) 2004, Raphael Manfredi
*
*----------------------------------------------------------------------
* This file is part of gtk-gnutella.
*
* gtk-gnutella 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.
*
* gtk-gnutella 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 gtk-gnutella; if not, write to the Free Software
* Foundation, Inc.:
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*----------------------------------------------------------------------
*/
/**
* @ingroup lib
* @file
*
* A FIFO.
*
* Items are put on one end and retrieved on the other, in the order
* they were put.
*
* @author Raphael Manfredi
* @date 2004
*/
#include "common.h"
RCSID("$Id: fifo.c 11437 2006-08-05 00:24:20Z cbiere $")
#include "fifo.h"
#include "walloc.h"
#include "override.h" /* Must be the last header included */
/**
* The real FIFO structure (the advertised fifo_t is just a facade).
*/
typedef struct fifo_real {
GList *head; /**< Head of FIFO, where data is prepended */
GList *tail; /**< Tail of FIFO, where data is removed from */
gint count; /**< Amount of entries in FIFO */
} fifo_real_t;
/**
* Create new FIFO.
*/
fifo_t *
fifo_make(void)
{
fifo_real_t *fr;
fr = walloc0(sizeof(*fr));
return (fifo_t *) fr;
}
/**
* Destroy FIFO.
*/
void
fifo_free(fifo_t *f)
{
fifo_real_t *fr = (fifo_real_t *) f;
g_list_free(fr->head);
wfree(fr, sizeof(*fr));
}
/**
* Destroy FIFO, invoking freeing callback on all items still held.
*
* @param f the FIFO to free
* @param cb the freeing callback to invoke on all items.
* @param udata the extra user data passed as-is to the freeing callback.
*/
void
fifo_free_all(fifo_t *f, fifo_free_t cb, gpointer udata)
{
fifo_real_t *fr = (fifo_real_t *) f;
GList *l;
for (l = fr->head; l; l = g_list_next(l))
(*cb)(l->data, udata);
fifo_free(f);
}
/**
* Returns amount of items queued in FIFO.
*/
gint
fifo_count(fifo_t *f)
{
fifo_real_t *fr = (fifo_real_t *) f;
return fr->count;
}
/**
* Add entry to FIFO.
*/
void
fifo_put(fifo_t *f, gconstpointer data)
{
fifo_real_t *fr = (fifo_real_t *) f;
g_assert(fr->count == 0 || fr->head != NULL);
g_assert(fr->count == 0 || fr->tail != NULL);
g_assert(fr->head == NULL || fr->count != 0);
g_assert(fr->tail == NULL || fr->count != 0);
fr->head = g_list_prepend(fr->head, (gpointer) data);
if (fr->tail == NULL)
fr->tail = fr->head;
fr->count++;
}
/**
* Remove entry from FIFO.
*
* @return the oldest item still held in FIFO, NULL if no item remains.
*/
gpointer
fifo_remove(fifo_t *f)
{
fifo_real_t *fr = (fifo_real_t *) f;
GList *prev;
gpointer data;
if (fr->count == 0)
return NULL;
g_assert(fr->tail != NULL);
data = fr->tail->data;
prev = g_list_previous(fr->tail);
if (prev == NULL) {
g_assert(fr->tail == fr->head);
g_assert(fr->count == 1);
fr->head = fr->tail = g_list_remove(fr->head, data);
} else {
fr->head = g_list_remove_link(fr->head, fr->tail);
g_list_free_1(fr->tail);
fr->tail = prev;
}
fr->count--;
g_assert(fr->count == 0 || fr->head != NULL);
g_assert(fr->count == 0 || fr->tail != NULL);
g_assert(fr->head == NULL || fr->count != 0);
g_assert(fr->tail == NULL || fr->count != 0);
return data;
}
See more files for this project here