/* $Id: dqueue.c,v 1.5 2003/04/12 21:40:49 schindler Exp $ * * Driver for Eicon DIVA Server ISDN cards. * User Mode IDI Interface * * Copyright 2000-2003 by Armin Schindler (mac@melware.de) * Copyright 2000-2003 Cytronics & Melware (info@melware.de) * * This software may be used and distributed according to the terms * of the GNU General Public License, incorporated herein by reference. */#include "platform.h"#include "dqueue.h"intdiva_data_q_init(diva_um_idi_data_queue_t * q,		 int max_length, int max_segments){	int i;	q->max_length = max_length;	q->segments = max_segments;	for (i = 0; i < q->segments; i++) {		q->data[i] = NULL;		q->length[i] = 0;	}	q->read = q->write = q->count = q->segment_pending = 0;	for (i = 0; i < q->segments; i++) {		if (!(q->data[i] = diva_os_malloc(0, q->max_length))) {			diva_data_q_finit(q);			return (-1);		}	}	return (0);}int diva_data_q_finit(diva_um_idi_data_queue_t * q){	int i;	for (i = 0; i < q->segments; i++) {		if (q->data[i]) {			diva_os_free(0, q->data[i]);		}		q->data[i] = NULL;		q->length[i] = 0;	}	q->read = q->write = q->count = q->segment_pending = 0;	return (0);}int diva_data_q_get_max_length(const diva_um_idi_data_queue_t * q){	return (q->max_length);}void *diva_data_q_get_segment4write(diva_um_idi_data_queue_t * q){	if ((!q->segment_pending) && (q->count < q->segments)) {		q->segment_pending = 1;		return (q->data[q->write]);	}	return NULL;}voiddiva_data_q_ack_segment4write(diva_um_idi_data_queue_t * q, int length){	if (q->segment_pending) {		q->length[q->write] = length;		q->count++;		q->write++;		if (q->write >= q->segments) {			q->write = 0;		}		q->segment_pending = 0;	}}const void *diva_data_q_get_segment4read(const diva_um_idi_data_queue_t *					 q){	if (q->count) {		return (q->data[q->read]);	}	return NULL;}int diva_data_q_get_segment_length(const diva_um_idi_data_queue_t * q){	return (q->length[q->read]);}void diva_data_q_ack_segment4read(diva_um_idi_data_queue_t * q){	if (q->count) {		q->length[q->read] = 0;		q->count--;		q->read++;		if (q->read >= q->segments) {			q->read = 0;		}	}}