lora-irrigation/comms.h

/*-
 * Copyright 2021 John-Mark Gurney.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

#include <sys/types.h>
#include <stdint.h>

#include <strobe.h>

#define COMMS_MAXMSG	64

struct pktbuf {
	uint8_t	*pkt;
	uint16_t pktlen;
};

/* first arg is input buffer, second arg is what will be sent as reply */
typedef void (*process_msgfunc_t)(struct pktbuf, struct pktbuf *);

enum comm_state {
	COMMS_WAIT_REQUEST = 1,
	COMMS_WAIT_CONFIRM,
	COMMS_PROCESS_MSGS,
};

struct comms_state {
	strobe_s		cs_state;
	enum comm_state		cs_comm_state;
	strobe_s		cs_start;	/* special starting state cache */

	process_msgfunc_t	cs_procmsg;

	struct pktbuf		cs_prevmsg;
	struct pktbuf		cs_prevmsgresp;

	uint8_t			cs_prevmsgbuf[COMMS_MAXMSG];
	uint8_t			cs_prevmsgrespbuf[COMMS_MAXMSG];
};

size_t _strobe_state_size();

void comms_init(struct comms_state *, process_msgfunc_t, struct pktbuf *);
void comms_process(struct comms_state *, struct pktbuf, struct pktbuf *);