#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#include <malloc.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include "serial.h"

char *serial_names[10] = {
	"",
	"/dev/ttyS0", "/dev/ttyS1", "/dev/ttyS2", "/dev/ttyS3",
	"/dev/usb/ttyUSB0", "/dev/usb/ttyUSB1", "/dev/usb/ttyUSB2", "/dev/usb/ttyUSB3",
	NULL };

serial_t *serial_open(const char *devname) {
	serial_t	*serport;

	serport = malloc(sizeof(serial_t));

	serport->fd = open(devname, O_RDWR|O_NOCTTY|O_NONBLOCK /*|O_SYNC*/);
	if (serport->fd < 0) {
		free(serport);
		return NULL;
	}

	return serport;
}

void	serial_setup(serial_t *serport) {
	struct termios	*tio1, *tio2;
	int		ret = 0;

	tio1 = &(serport->oldtio);
	tio2 = &(serport->newtio);

	if (tcgetattr(serport->fd, tio1))
		ret = -1;
	memcpy(tio2, tio1, sizeof(struct termios));
	cfmakeraw(tio2);
	cfsetospeed(tio2, B115200);
	cfsetispeed(tio2, B115200);
#if 0
	tio2->c_cflag |= CRTSCTS;
#endif
	tio2->c_cflag |= CREAD|CLOCAL;
	tcflush(serport->fd, TCIOFLUSH);
	if (tcsetattr(serport->fd, TCSANOW, tio2))
		ret = -1;
#if 0
	tcflow(serport->fd, TCOON); tcflow(serport->fd, TCION);
#endif
	serport->err = ret;
}

void	serial_close(serial_t *serport) {
	tcflush(serport->fd, TCIOFLUSH);
	tcsetattr(serport->fd, TCSANOW, &(serport->oldtio));
	close(serport->fd);
	free(serport);
}

void	serial_write(serial_t *serport, const char *buffer, size_t n) {
	int	i;

	serport->err = write(serport->fd, buffer, n);
	tcdrain(serport->fd);
}

void serial_read(serial_t *serport, char *buffer, size_t n, int wait) {
	int pos = 0;
	int err = 0;
	struct timeval tv;
	fd_set set;

	if (wait) {
		FD_ZERO(&set);
		FD_SET(serport->fd, &set);
		tv.tv_sec = 0;
		tv.tv_usec = 250000;
		serport->err = select(serport->fd+1, &set, NULL, NULL, &tv);
		if (serport->err <= 0)
			return;
	}

	while(n--) {
again:
		if (wait) {
			FD_ZERO(&set);
			FD_SET(serport->fd, &set);
			tv.tv_sec = 0;
			tv.tv_usec = 100000;
			serport->err = select(serport->fd+1, &set, NULL, NULL, &tv);
			if (serport->err <= 0)
				return;
		}
		serport->err = read(serport->fd, &buffer[pos++], 1);
		if (serport->err == 0)
			goto again;
		if (serport->err == -1)
			break;
	}
	if (serport->err != -1)
		serport->err = pos;
}

void	serial_delay(int ms) {
	usleep(ms*1000);
}