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/*
* ppstest.c -- simple tool to monitor PPS timestamps
*
* Copyright (C) 2005-2007 Rodolfo Giometti <giometti@linux.it>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "timepps.h"
static struct timespec offset_assert = {0, 0};
int find_source(char *path, pps_handle_t *handle, int *avail_mode)
{
pps_params_t params;
int ret;
printf("trying PPS source \"%s\"\n", path);
/* Try to find the source by using the supplied "path" name */
ret = open(path, O_RDWR);
if (ret < 0) {
fprintf(stderr, "unable to open device \"%s\" (%m)\n", path);
return ret;
}
/* Open the PPS source (and check the file descriptor) */
ret = time_pps_create(ret, handle);
if (ret < 0) {
fprintf(stderr, "cannot create a PPS source from device "
"\"%s\" (%m)\n", path);
return -1;
}
printf("found PPS source \"%s\"\n", path);
/* Find out what features are supported */
ret = time_pps_getcap(*handle, avail_mode);
if (ret < 0) {
fprintf(stderr, "cannot get capabilities (%m)\n");
return -1;
}
if ((*avail_mode & PPS_CAPTUREASSERT) == 0) {
fprintf(stderr, "cannot CAPTUREASSERT\n");
return -1;
}
/* Capture assert timestamps */
ret = time_pps_getparams(*handle, ¶ms);
if (ret < 0) {
fprintf(stderr, "cannot get parameters (%m)\n");
return -1;
}
params.mode |= PPS_CAPTUREASSERT;
/* Override any previous offset if possible */
if ((*avail_mode & PPS_OFFSETASSERT) != 0) {
params.mode |= PPS_OFFSETASSERT;
params.assert_offset = offset_assert;
}
ret = time_pps_setparams(*handle, ¶ms);
if (ret < 0) {
fprintf(stderr, "cannot set parameters (%m)\n");
return -1;
}
return 0;
}
int fetch_source(int i, pps_handle_t *handle, int *avail_mode)
{
struct timespec timeout;
pps_info_t infobuf;
int ret;
/* create a zero-valued timeout */
timeout.tv_sec = 3;
timeout.tv_nsec = 0;
retry:
if (*avail_mode & PPS_CANWAIT) /* waits for the next event */
ret = time_pps_fetch(*handle, PPS_TSFMT_TSPEC, &infobuf,
&timeout);
else {
sleep(1);
ret = time_pps_fetch(*handle, PPS_TSFMT_TSPEC, &infobuf,
&timeout);
}
if (ret < 0) {
if (ret == -EINTR) {
fprintf(stderr, "time_pps_fetch() got a signal!\n");
goto retry;
}
fprintf(stderr, "time_pps_fetch() error %d (%m)\n", ret);
return -1;
}
printf("source %d - "
"assert %ld.%09ld, sequence: %ld - "
"clear %ld.%09ld, sequence: %ld\n",
i,
infobuf.assert_timestamp.tv_sec,
infobuf.assert_timestamp.tv_nsec,
infobuf.assert_sequence,
infobuf.clear_timestamp.tv_sec,
infobuf.clear_timestamp.tv_nsec, infobuf.clear_sequence);
fflush(stdout);
return 0;
}
void usage(char *name)
{
fprintf(stderr, "usage: %s <ppsdev> [<ppsdev> ...]\n", name);
exit(EXIT_FAILURE);
}
int main(int argc, char *argv[])
{
int num;
pps_handle_t handle[4];
int avail_mode[4];
int i = 0;
int ret;
/* Check the command line */
if (argc < 2)
usage(argv[0]);
for (i = 1; i < argc && i <= 4; i++) {
ret = find_source(argv[i], &handle[i - 1], &avail_mode[i - 1]);
if (ret < 0)
exit(EXIT_FAILURE);
}
num = i - 1;
printf("ok, found %d source(s), now start fetching data...\n", num);
/* loop, printing the most recent timestamp every second or so */
while (1) {
for (i = 0; i < num; i++) {
ret = fetch_source(i, &handle[i], &avail_mode[i]);
if (ret < 0 && errno != ETIMEDOUT)
exit(EXIT_FAILURE);
}
}
for (; i >= 0; i--)
time_pps_destroy(handle[i]);
return 0;
}
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