paulo@0: /*
paulo@0:  * $Id: tx_layer.h,v 1.5 2004/01/31 13:33:17 hipnod Exp $
paulo@0:  *
paulo@0:  * Copyright (C) 2003 giFT project (gift.sourceforge.net)
paulo@0:  *
paulo@0:  * This program is free software; you can redistribute it and/or modify it
paulo@0:  * under the terms of the GNU General Public License as published by the
paulo@0:  * Free Software Foundation; either version 2, or (at your option) any
paulo@0:  * later version.
paulo@0:  *
paulo@0:  * This program is distributed in the hope that it will be useful, but
paulo@0:  * WITHOUT ANY WARRANTY; without even the implied warranty of
paulo@0:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
paulo@0:  * General Public License for more details.
paulo@0:  */
paulo@0: 
paulo@0: #ifndef GIFT_GT_TX_LAYER_H_
paulo@0: #define GIFT_GT_TX_LAYER_H_
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: struct tx_layer_ops;
paulo@0: struct tx_layer;
paulo@0: 
paulo@0: struct io_buf;
paulo@0: struct gt_tx_stack;
paulo@0: 
paulo@0: /*
paulo@0:  * Return codes from the TX stack functions that lets the caller know
paulo@0:  * what processing occured.
paulo@0:  */
paulo@0: typedef enum tx_status
paulo@0: {
paulo@0: 	TX_OK,
paulo@0: 	TX_FULL,             /* lower layer became saturated */
paulo@0: 	TX_EMPTY,            /* no waiting data */
paulo@0: 	TX_PARTIAL,          /* buffer partially read */
paulo@0: 	TX_ERROR,            /* general error */
paulo@0: } tx_status_t;
paulo@0: 
paulo@0: struct tx_layer_ops
paulo@0: {
paulo@0: 	BOOL        (*init)       (struct tx_layer *tx);
paulo@0: 	void        (*destroy)    (struct tx_layer *tx);
paulo@0: 
paulo@0: 	/*
paulo@0: 	 * If the layer is capable of consuming data (for example
paulo@0: 	 * by sending it out on a connection), begin or stop flushing by obeying
paulo@0: 	 * the 'stop' argument.  Only the bottommost layer in a stack
paulo@0: 	 * should implement this.
paulo@0: 	 */
paulo@0: 	void        (*toggle)     (struct tx_layer *tx, BOOL stop);
paulo@0: 
paulo@0: 	/* upper layer has sent us a buffer */
paulo@0: 	tx_status_t (*queue)      (struct tx_layer *tx, struct io_buf *io_buf);
paulo@0: 
paulo@0: 	/* lower layer wants us to send a buffer */
paulo@0: 	tx_status_t (*ready)      (struct tx_layer *tx);   /* lower layer wants data */
paulo@0: 
paulo@0: 	/* enable/disable this layer completely */
paulo@0: 	void        (*enable)     (struct tx_layer *tx);
paulo@0: 	void        (*disable)    (struct tx_layer *tx);
paulo@0: };
paulo@0: 
paulo@0: struct tx_layer
paulo@0: {
paulo@0: 	void                *udata;
paulo@0: 	struct tx_layer_ops *ops;
paulo@0: 
paulo@0: 	struct tx_layer     *upper;
paulo@0: 	struct tx_layer     *lower;
paulo@0: 
paulo@0: 	/* leftovers from previous queue operations */
paulo@0: 	struct io_buf       *partial_buf;
paulo@0: 
paulo@0: 	struct gt_tx_stack  *stack;
paulo@0: 	const char          *name;
paulo@0: };
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: struct tx_layer *gt_tx_layer_new      (struct gt_tx_stack *stack,
paulo@0:                                        const char *name,
paulo@0:                                        struct tx_layer_ops *ops);
paulo@0: void             gt_tx_layer_free     (struct tx_layer *layer);
paulo@0: 
paulo@0: void             gt_tx_layer_enable   (struct tx_layer *layer);
paulo@0: void             gt_tx_layer_disable  (struct tx_layer *layer);
paulo@0: 
paulo@0: tx_status_t      gt_tx_layer_queue    (struct tx_layer *layer,
paulo@0:                                        struct io_buf *buf);
paulo@0: tx_status_t      gt_tx_layer_ready    (struct tx_layer *layer);
paulo@0: 
paulo@0: /*****************************************************************************/
paulo@0: 
paulo@0: #endif /* GIFT_GT_TX_LAYER_H_ */