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#include "config.h"
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
#if defined(HAVE_SYS_MODEM_H)
#include <sys/modem.h>
#endif /* HAVE_SYS_MODEM_H */
#include "gpsd.h"
/* Workaround for HP-UX 11.23, which is missing CRTSCTS */
#ifndef CRTSCTS
# ifdef CNEW_RTSCTS
# define CRTSCTS CNEW_RTSCTS
# else
# define CRTSCTS 0
# endif /* CNEW_RTSCTS */
#endif /* !CRTSCTS */
int gpsd_set_speed(int ttyfd, struct termios *ttyctl, int device_speed)
{
if (device_speed < 300)
device_speed = 0;
else if (device_speed < 1200)
device_speed = B300;
else if (device_speed < 2400)
device_speed = B1200;
else if (device_speed < 4800)
device_speed = B2400;
else if (device_speed < 9600)
device_speed = B4800;
else if (device_speed < 19200)
device_speed = B9600;
else if (device_speed < 38400)
device_speed = B19200;
else
device_speed = B38400;
cfsetispeed(ttyctl, (speed_t)device_speed);
cfsetospeed(ttyctl, (speed_t)device_speed);
if (tcsetattr(ttyfd, TCSAFLUSH, ttyctl) != 0)
return 0;
/*
* for unknown reasons, the TCSAFLUSH above is not sufficient to
* flush the stale data from previous hunting out of the buffer.
*/
tcflush(ttyfd, TCIOFLUSH);
/*
* Give the GPS and UART this much time to settle and ship some data
* before trying to read after open or baud rate change. Less than
* 1.25 seconds doesn't work om most UARTs.
*/
usleep(1250000);
return 1;
}
int gpsd_get_speed(struct termios* ttyctl)
{
int code = cfgetospeed(ttyctl);
switch (code) {
case B0: return(0);
case B300: return(300);
case B1200: return(1200);
case B2400: return(2400);
case B4800: return(4800);
case B9600: return(9600);
case B19200: return(19200);
default: return(38400);
}
}
/* every rate we're likely to see on a GPS */
static int rates[] = {4800, 9600, 19200, 38400};
#define NRATES sizeof(rates)/sizeof(rates[0])
static int connect_at_speed(int ttyfd, struct gps_session_t *session, int speed)
{
char buf[BUFSIZE];
int n;
size_t maxreads;
gpsd_set_speed(ttyfd, &session->ttyset, speed);
buf[0] = '\0';
for (maxreads = 0; maxreads < NRATES; maxreads++) {
n = read(ttyfd, buf, sizeof(buf)-1);
if (n > 0) {
buf[n] = '\0';
break;
}
else if (n == -1 && errno != EAGAIN)
return 0;
}
if (session->device_type->validate_buffer)
return session->device_type->validate_buffer(buf, n);
else
return 1;
}
int gpsd_open(int device_speed, int stopbits, struct gps_session_t *session)
{
int ttyfd, *ip;
gpsd_report(1, "opening GPS data source at %s\n", session->gpsd_device);
if ((ttyfd = open(session->gpsd_device, O_RDWR | O_NONBLOCK)) < 0)
return -1;
if (isatty(ttyfd)) {
/* Save original terminal parameters */
if (tcgetattr(ttyfd,&session->ttyset_old) != 0)
return -1;
memcpy(&session->ttyset,&session->ttyset_old,sizeof(session->ttyset));
/*
* Tip from Chris Kuethe: the FIDI chip used in the Trip-Nav
* 200 (and possibly other USB GPSes) gets completely hosed
* in the presence of flow control. Thus, turn off CRTSCTS.
*/
session->ttyset.c_cflag &= ~(PARENB | CRTSCTS);
session->ttyset.c_cflag |= (CSIZE & (stopbits==2 ? CS7 : CS8)) | CREAD | CLOCAL;
session->ttyset.c_iflag = session->ttyset.c_oflag = session->ttyset.c_lflag = (tcflag_t) 0;
session->ttyset.c_oflag = (ONLCR);
if (device_speed) {
gpsd_report(1, "setting speed %d, %d stopbits, no parity\n",
device_speed, stopbits);
if (connect_at_speed(ttyfd, session, device_speed)) {
session->gNMEAdata.baudrate = device_speed;
return ttyfd;
}
} else
for (ip = rates; ip < rates + sizeof(rates)/sizeof(rates[0]); ip++) {
gpsd_report(1, "hunting at speed %d, %d stopbits, no parity\n",
*ip, stopbits);
if (connect_at_speed(ttyfd, session, *ip)) {
session->gNMEAdata.baudrate = *ip;
return ttyfd;
}
}
return -1;
}
return ttyfd;
}
void gpsd_close(struct gps_session_t *session)
{
if (session->gNMEAdata.gps_fd != -1) {
if (isatty(session->gNMEAdata.gps_fd)) {
/* force hangup on close on systems that don't do HUPCL properly */
cfsetispeed(&session->ttyset, (speed_t)B0);
cfsetospeed(&session->ttyset, (speed_t)B0);
tcsetattr(session->gNMEAdata.gps_fd, TCSANOW, &session->ttyset);
}
/* this is the clean way to do it */
session->ttyset_old.c_cflag |= HUPCL;
tcsetattr(session->gNMEAdata.gps_fd,TCSANOW,&session->ttyset_old);
close(session->gNMEAdata.gps_fd);
}
}
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