/*
 * This module takes care of opening the serial port and setting the
 * proper "raw" termios modes, including the baud rate.
 */

#include <sys/types.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <termios.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>

int target_fd;
char *baudrate_name = "115200";

static struct baudrate {
	char	*name;
	speed_t	termios_code;
} baud_rate_table[] = {
	{"19200",	B19200},
	{"38400",	B38400},
	{"57600",	B57600},
	{"115200",	B115200},
	/* non-standard high baud rates "remapped" by CP2102 usb2serial IC */
	{"203125",	B230400},
	{"406250",	B460800},
	{"812500",	B921600},
	/* table search terminator */
	{NULL,		B0}
};

static speed_t
get_baud_rate()
{
	struct baudrate *br;

	for (br = baud_rate_table; br->name; br++)
		if (!strcmp(br->name, baudrate_name))
			break;
	if (!br->name) {
		fprintf(stderr, "baud rate \"%s\" unknown/unsupported\n",
			baudrate_name);
		exit(1);
	}
	return br->termios_code;
}

open_target_serial(ttydev)
	char *ttydev;
{
	struct termios target_termios;
	speed_t br_code;

	br_code = get_baud_rate();
	target_fd = open(ttydev, O_RDWR|O_NONBLOCK);
	if (target_fd < 0) {
		perror(ttydev);
		exit(1);
	}
	target_termios.c_iflag = IGNBRK;
	target_termios.c_oflag = 0;
	target_termios.c_cflag = CLOCAL|HUPCL|CREAD|CS8;
	target_termios.c_lflag = 0;
	target_termios.c_cc[VMIN] = 1;
	target_termios.c_cc[VTIME] = 0;
	cfsetispeed(&target_termios, br_code);
	cfsetospeed(&target_termios, br_code);
	if (tcsetattr(target_fd, TCSAFLUSH, &target_termios) < 0) {
		perror("initial tcsetattr on target");
		exit(1);
	}
	ioctl(target_fd, TIOCEXCL);
	return 0;
}

set_serial_nonblock(state)
	int state;
{
	ioctl(target_fd, FIONBIO, &state);
}