529 lines
15 KiB
C
529 lines
15 KiB
C
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/*
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* This program demonstrates how the various time stamping features in
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* the Linux kernel work. It emulates the behavior of a PTP
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* implementation in stand-alone master mode by sending PTPv1 Sync
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* multicasts once every second. It looks for similar packets, but
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* beyond that doesn't actually implement PTP.
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*
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* Outgoing packets are time stamped with SO_TIMESTAMPING with or
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* without hardware support.
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*
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* Incoming packets are time stamped with SO_TIMESTAMPING with or
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* without hardware support, SIOCGSTAMP[NS] (per-socket time stamp) and
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* SO_TIMESTAMP[NS].
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*
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* Copyright (C) 2009 Intel Corporation.
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* Author: Patrick Ohly <patrick.ohly@intel.com>
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*
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* This program is free software; you can redistribute it and/or modify it
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* under the terms and conditions of the GNU General Public License,
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* version 2, as published by the Free Software Foundation.
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*
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* This program is distributed in the hope it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. * See the GNU General Public License for
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* more details.
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*
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* You should have received a copy of the GNU General Public License along with
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* this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <errno.h>
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#include <string.h>
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#include <sys/time.h>
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#include <sys/socket.h>
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#include <sys/select.h>
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#include <sys/ioctl.h>
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#include <arpa/inet.h>
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#include <net/if.h>
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#include <asm/types.h>
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#include <linux/net_tstamp.h>
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#include <linux/errqueue.h>
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#ifndef SO_TIMESTAMPING
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# define SO_TIMESTAMPING 37
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# define SCM_TIMESTAMPING SO_TIMESTAMPING
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#endif
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#ifndef SO_TIMESTAMPNS
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# define SO_TIMESTAMPNS 35
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#endif
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#ifndef SIOCGSTAMPNS
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# define SIOCGSTAMPNS 0x8907
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#endif
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#ifndef SIOCSHWTSTAMP
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# define SIOCSHWTSTAMP 0x89b0
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#endif
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static void usage(const char *error)
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{
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if (error)
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printf("invalid option: %s\n", error);
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printf("timestamping interface option*\n\n"
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"Options:\n"
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" IP_MULTICAST_LOOP - looping outgoing multicasts\n"
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" SO_TIMESTAMP - normal software time stamping, ms resolution\n"
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" SO_TIMESTAMPNS - more accurate software time stamping\n"
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" SOF_TIMESTAMPING_TX_HARDWARE - hardware time stamping of outgoing packets\n"
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" SOF_TIMESTAMPING_TX_SOFTWARE - software fallback for outgoing packets\n"
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" SOF_TIMESTAMPING_RX_HARDWARE - hardware time stamping of incoming packets\n"
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" SOF_TIMESTAMPING_RX_SOFTWARE - software fallback for incoming packets\n"
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" SOF_TIMESTAMPING_SOFTWARE - request reporting of software time stamps\n"
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" SOF_TIMESTAMPING_RAW_HARDWARE - request reporting of raw HW time stamps\n"
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" SIOCGSTAMP - check last socket time stamp\n"
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" SIOCGSTAMPNS - more accurate socket time stamp\n");
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exit(1);
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}
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static void bail(const char *error)
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{
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printf("%s: %s\n", error, strerror(errno));
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exit(1);
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}
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static const unsigned char sync[] = {
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0x00, 0x01, 0x00, 0x01,
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0x5f, 0x44, 0x46, 0x4c,
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0x54, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x00,
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0x01, 0x01,
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/* fake uuid */
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0x00, 0x01,
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0x02, 0x03, 0x04, 0x05,
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0x00, 0x01, 0x00, 0x37,
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0x00, 0x00, 0x00, 0x08,
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0x00, 0x00, 0x00, 0x00,
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0x49, 0x05, 0xcd, 0x01,
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0x29, 0xb1, 0x8d, 0xb0,
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0x00, 0x00, 0x00, 0x00,
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0x00, 0x01,
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/* fake uuid */
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0x00, 0x01,
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0x02, 0x03, 0x04, 0x05,
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0x00, 0x00, 0x00, 0x37,
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0x00, 0x00, 0x00, 0x04,
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0x44, 0x46, 0x4c, 0x54,
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0x00, 0x00, 0xf0, 0x60,
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0x00, 0x01, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x01,
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0x00, 0x00, 0xf0, 0x60,
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0x00, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x04,
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0x44, 0x46, 0x4c, 0x54,
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0x00, 0x01,
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/* fake uuid */
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0x00, 0x01,
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0x02, 0x03, 0x04, 0x05,
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0x00, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x00,
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0x00, 0x00, 0x00, 0x00
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};
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static void sendpacket(int sock, struct sockaddr *addr, socklen_t addr_len)
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{
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struct timeval now;
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int res;
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res = sendto(sock, sync, sizeof(sync), 0,
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addr, addr_len);
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gettimeofday(&now, 0);
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if (res < 0)
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printf("%s: %s\n", "send", strerror(errno));
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else
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printf("%ld.%06ld: sent %d bytes\n",
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(long)now.tv_sec, (long)now.tv_usec,
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res);
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}
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static void printpacket(struct msghdr *msg, int res,
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char *data,
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int sock, int recvmsg_flags,
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int siocgstamp, int siocgstampns)
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{
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struct sockaddr_in *from_addr = (struct sockaddr_in *)msg->msg_name;
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struct cmsghdr *cmsg;
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struct timeval tv;
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struct timespec ts;
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struct timeval now;
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gettimeofday(&now, 0);
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printf("%ld.%06ld: received %s data, %d bytes from %s, %zu bytes control messages\n",
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(long)now.tv_sec, (long)now.tv_usec,
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(recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular",
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res,
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inet_ntoa(from_addr->sin_addr),
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msg->msg_controllen);
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for (cmsg = CMSG_FIRSTHDR(msg);
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cmsg;
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cmsg = CMSG_NXTHDR(msg, cmsg)) {
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printf(" cmsg len %zu: ", cmsg->cmsg_len);
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switch (cmsg->cmsg_level) {
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case SOL_SOCKET:
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printf("SOL_SOCKET ");
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switch (cmsg->cmsg_type) {
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case SO_TIMESTAMP: {
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struct timeval *stamp =
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(struct timeval *)CMSG_DATA(cmsg);
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printf("SO_TIMESTAMP %ld.%06ld",
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(long)stamp->tv_sec,
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(long)stamp->tv_usec);
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break;
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}
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case SO_TIMESTAMPNS: {
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struct timespec *stamp =
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(struct timespec *)CMSG_DATA(cmsg);
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printf("SO_TIMESTAMPNS %ld.%09ld",
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(long)stamp->tv_sec,
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(long)stamp->tv_nsec);
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break;
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}
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case SO_TIMESTAMPING: {
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struct timespec *stamp =
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(struct timespec *)CMSG_DATA(cmsg);
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printf("SO_TIMESTAMPING ");
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printf("SW %ld.%09ld ",
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(long)stamp->tv_sec,
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(long)stamp->tv_nsec);
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stamp++;
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/* skip deprecated HW transformed */
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stamp++;
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printf("HW raw %ld.%09ld",
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(long)stamp->tv_sec,
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(long)stamp->tv_nsec);
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break;
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}
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default:
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printf("type %d", cmsg->cmsg_type);
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break;
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}
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break;
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case IPPROTO_IP:
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printf("IPPROTO_IP ");
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switch (cmsg->cmsg_type) {
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case IP_RECVERR: {
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struct sock_extended_err *err =
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(struct sock_extended_err *)CMSG_DATA(cmsg);
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printf("IP_RECVERR ee_errno '%s' ee_origin %d => %s",
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strerror(err->ee_errno),
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err->ee_origin,
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#ifdef SO_EE_ORIGIN_TIMESTAMPING
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err->ee_origin == SO_EE_ORIGIN_TIMESTAMPING ?
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"bounced packet" : "unexpected origin"
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#else
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"probably SO_EE_ORIGIN_TIMESTAMPING"
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#endif
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);
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if (res < sizeof(sync))
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printf(" => truncated data?!");
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else if (!memcmp(sync, data + res - sizeof(sync),
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sizeof(sync)))
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printf(" => GOT OUR DATA BACK (HURRAY!)");
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break;
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}
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case IP_PKTINFO: {
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struct in_pktinfo *pktinfo =
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(struct in_pktinfo *)CMSG_DATA(cmsg);
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printf("IP_PKTINFO interface index %u",
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pktinfo->ipi_ifindex);
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break;
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}
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default:
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printf("type %d", cmsg->cmsg_type);
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break;
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}
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break;
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default:
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printf("level %d type %d",
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cmsg->cmsg_level,
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cmsg->cmsg_type);
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break;
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}
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printf("\n");
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}
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if (siocgstamp) {
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if (ioctl(sock, SIOCGSTAMP, &tv))
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printf(" %s: %s\n", "SIOCGSTAMP", strerror(errno));
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else
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printf("SIOCGSTAMP %ld.%06ld\n",
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(long)tv.tv_sec,
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(long)tv.tv_usec);
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}
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if (siocgstampns) {
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if (ioctl(sock, SIOCGSTAMPNS, &ts))
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printf(" %s: %s\n", "SIOCGSTAMPNS", strerror(errno));
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else
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printf("SIOCGSTAMPNS %ld.%09ld\n",
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(long)ts.tv_sec,
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(long)ts.tv_nsec);
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}
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}
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static void recvpacket(int sock, int recvmsg_flags,
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int siocgstamp, int siocgstampns)
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{
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char data[256];
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struct msghdr msg;
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struct iovec entry;
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struct sockaddr_in from_addr;
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struct {
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struct cmsghdr cm;
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char control[512];
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} control;
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int res;
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memset(&msg, 0, sizeof(msg));
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msg.msg_iov = &entry;
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msg.msg_iovlen = 1;
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entry.iov_base = data;
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entry.iov_len = sizeof(data);
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msg.msg_name = (caddr_t)&from_addr;
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msg.msg_namelen = sizeof(from_addr);
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msg.msg_control = &control;
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msg.msg_controllen = sizeof(control);
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res = recvmsg(sock, &msg, recvmsg_flags|MSG_DONTWAIT);
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if (res < 0) {
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printf("%s %s: %s\n",
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"recvmsg",
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(recvmsg_flags & MSG_ERRQUEUE) ? "error" : "regular",
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strerror(errno));
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} else {
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printpacket(&msg, res, data,
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sock, recvmsg_flags,
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siocgstamp, siocgstampns);
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}
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}
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int main(int argc, char **argv)
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{
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int so_timestamping_flags = 0;
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int so_timestamp = 0;
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int so_timestampns = 0;
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int siocgstamp = 0;
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int siocgstampns = 0;
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int ip_multicast_loop = 0;
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char *interface;
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int i;
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int enabled = 1;
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int sock;
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struct ifreq device;
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struct ifreq hwtstamp;
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struct hwtstamp_config hwconfig, hwconfig_requested;
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struct sockaddr_in addr;
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struct ip_mreq imr;
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struct in_addr iaddr;
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int val;
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socklen_t len;
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struct timeval next;
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if (argc < 2)
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usage(0);
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interface = argv[1];
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for (i = 2; i < argc; i++) {
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if (!strcasecmp(argv[i], "SO_TIMESTAMP"))
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so_timestamp = 1;
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else if (!strcasecmp(argv[i], "SO_TIMESTAMPNS"))
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so_timestampns = 1;
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else if (!strcasecmp(argv[i], "SIOCGSTAMP"))
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siocgstamp = 1;
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else if (!strcasecmp(argv[i], "SIOCGSTAMPNS"))
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siocgstampns = 1;
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else if (!strcasecmp(argv[i], "IP_MULTICAST_LOOP"))
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ip_multicast_loop = 1;
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else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_TX_HARDWARE"))
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so_timestamping_flags |= SOF_TIMESTAMPING_TX_HARDWARE;
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else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_TX_SOFTWARE"))
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so_timestamping_flags |= SOF_TIMESTAMPING_TX_SOFTWARE;
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else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RX_HARDWARE"))
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so_timestamping_flags |= SOF_TIMESTAMPING_RX_HARDWARE;
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else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RX_SOFTWARE"))
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so_timestamping_flags |= SOF_TIMESTAMPING_RX_SOFTWARE;
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else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_SOFTWARE"))
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so_timestamping_flags |= SOF_TIMESTAMPING_SOFTWARE;
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else if (!strcasecmp(argv[i], "SOF_TIMESTAMPING_RAW_HARDWARE"))
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so_timestamping_flags |= SOF_TIMESTAMPING_RAW_HARDWARE;
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else
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usage(argv[i]);
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}
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sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
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if (sock < 0)
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bail("socket");
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memset(&device, 0, sizeof(device));
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strncpy(device.ifr_name, interface, sizeof(device.ifr_name));
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if (ioctl(sock, SIOCGIFADDR, &device) < 0)
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bail("getting interface IP address");
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memset(&hwtstamp, 0, sizeof(hwtstamp));
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strncpy(hwtstamp.ifr_name, interface, sizeof(hwtstamp.ifr_name));
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hwtstamp.ifr_data = (void *)&hwconfig;
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memset(&hwconfig, 0, sizeof(hwconfig));
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hwconfig.tx_type =
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(so_timestamping_flags & SOF_TIMESTAMPING_TX_HARDWARE) ?
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HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF;
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hwconfig.rx_filter =
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(so_timestamping_flags & SOF_TIMESTAMPING_RX_HARDWARE) ?
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HWTSTAMP_FILTER_PTP_V1_L4_SYNC : HWTSTAMP_FILTER_NONE;
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hwconfig_requested = hwconfig;
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if (ioctl(sock, SIOCSHWTSTAMP, &hwtstamp) < 0) {
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if ((errno == EINVAL || errno == ENOTSUP) &&
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hwconfig_requested.tx_type == HWTSTAMP_TX_OFF &&
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hwconfig_requested.rx_filter == HWTSTAMP_FILTER_NONE)
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printf("SIOCSHWTSTAMP: disabling hardware time stamping not possible\n");
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else
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bail("SIOCSHWTSTAMP");
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}
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printf("SIOCSHWTSTAMP: tx_type %d requested, got %d; rx_filter %d requested, got %d\n",
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hwconfig_requested.tx_type, hwconfig.tx_type,
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hwconfig_requested.rx_filter, hwconfig.rx_filter);
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/* bind to PTP port */
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addr.sin_family = AF_INET;
|
||
|
addr.sin_addr.s_addr = htonl(INADDR_ANY);
|
||
|
addr.sin_port = htons(319 /* PTP event port */);
|
||
|
if (bind(sock,
|
||
|
(struct sockaddr *)&addr,
|
||
|
sizeof(struct sockaddr_in)) < 0)
|
||
|
bail("bind");
|
||
|
|
||
|
/* set multicast group for outgoing packets */
|
||
|
inet_aton("224.0.1.130", &iaddr); /* alternate PTP domain 1 */
|
||
|
addr.sin_addr = iaddr;
|
||
|
imr.imr_multiaddr.s_addr = iaddr.s_addr;
|
||
|
imr.imr_interface.s_addr =
|
||
|
((struct sockaddr_in *)&device.ifr_addr)->sin_addr.s_addr;
|
||
|
if (setsockopt(sock, IPPROTO_IP, IP_MULTICAST_IF,
|
||
|
&imr.imr_interface.s_addr, sizeof(struct in_addr)) < 0)
|
||
|
bail("set multicast");
|
||
|
|
||
|
/* join multicast group, loop our own packet */
|
||
|
if (setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP,
|
||
|
&imr, sizeof(struct ip_mreq)) < 0)
|
||
|
bail("join multicast group");
|
||
|
|
||
|
if (setsockopt(sock, IPPROTO_IP, IP_MULTICAST_LOOP,
|
||
|
&ip_multicast_loop, sizeof(enabled)) < 0) {
|
||
|
bail("loop multicast");
|
||
|
}
|
||
|
|
||
|
/* set socket options for time stamping */
|
||
|
if (so_timestamp &&
|
||
|
setsockopt(sock, SOL_SOCKET, SO_TIMESTAMP,
|
||
|
&enabled, sizeof(enabled)) < 0)
|
||
|
bail("setsockopt SO_TIMESTAMP");
|
||
|
|
||
|
if (so_timestampns &&
|
||
|
setsockopt(sock, SOL_SOCKET, SO_TIMESTAMPNS,
|
||
|
&enabled, sizeof(enabled)) < 0)
|
||
|
bail("setsockopt SO_TIMESTAMPNS");
|
||
|
|
||
|
if (so_timestamping_flags &&
|
||
|
setsockopt(sock, SOL_SOCKET, SO_TIMESTAMPING,
|
||
|
&so_timestamping_flags,
|
||
|
sizeof(so_timestamping_flags)) < 0)
|
||
|
bail("setsockopt SO_TIMESTAMPING");
|
||
|
|
||
|
/* request IP_PKTINFO for debugging purposes */
|
||
|
if (setsockopt(sock, SOL_IP, IP_PKTINFO,
|
||
|
&enabled, sizeof(enabled)) < 0)
|
||
|
printf("%s: %s\n", "setsockopt IP_PKTINFO", strerror(errno));
|
||
|
|
||
|
/* verify socket options */
|
||
|
len = sizeof(val);
|
||
|
if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMP, &val, &len) < 0)
|
||
|
printf("%s: %s\n", "getsockopt SO_TIMESTAMP", strerror(errno));
|
||
|
else
|
||
|
printf("SO_TIMESTAMP %d\n", val);
|
||
|
|
||
|
if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMPNS, &val, &len) < 0)
|
||
|
printf("%s: %s\n", "getsockopt SO_TIMESTAMPNS",
|
||
|
strerror(errno));
|
||
|
else
|
||
|
printf("SO_TIMESTAMPNS %d\n", val);
|
||
|
|
||
|
if (getsockopt(sock, SOL_SOCKET, SO_TIMESTAMPING, &val, &len) < 0) {
|
||
|
printf("%s: %s\n", "getsockopt SO_TIMESTAMPING",
|
||
|
strerror(errno));
|
||
|
} else {
|
||
|
printf("SO_TIMESTAMPING %d\n", val);
|
||
|
if (val != so_timestamping_flags)
|
||
|
printf(" not the expected value %d\n",
|
||
|
so_timestamping_flags);
|
||
|
}
|
||
|
|
||
|
/* send packets forever every five seconds */
|
||
|
gettimeofday(&next, 0);
|
||
|
next.tv_sec = (next.tv_sec + 1) / 5 * 5;
|
||
|
next.tv_usec = 0;
|
||
|
while (1) {
|
||
|
struct timeval now;
|
||
|
struct timeval delta;
|
||
|
long delta_us;
|
||
|
int res;
|
||
|
fd_set readfs, errorfs;
|
||
|
|
||
|
gettimeofday(&now, 0);
|
||
|
delta_us = (long)(next.tv_sec - now.tv_sec) * 1000000 +
|
||
|
(long)(next.tv_usec - now.tv_usec);
|
||
|
if (delta_us > 0) {
|
||
|
/* continue waiting for timeout or data */
|
||
|
delta.tv_sec = delta_us / 1000000;
|
||
|
delta.tv_usec = delta_us % 1000000;
|
||
|
|
||
|
FD_ZERO(&readfs);
|
||
|
FD_ZERO(&errorfs);
|
||
|
FD_SET(sock, &readfs);
|
||
|
FD_SET(sock, &errorfs);
|
||
|
printf("%ld.%06ld: select %ldus\n",
|
||
|
(long)now.tv_sec, (long)now.tv_usec,
|
||
|
delta_us);
|
||
|
res = select(sock + 1, &readfs, 0, &errorfs, &delta);
|
||
|
gettimeofday(&now, 0);
|
||
|
printf("%ld.%06ld: select returned: %d, %s\n",
|
||
|
(long)now.tv_sec, (long)now.tv_usec,
|
||
|
res,
|
||
|
res < 0 ? strerror(errno) : "success");
|
||
|
if (res > 0) {
|
||
|
if (FD_ISSET(sock, &readfs))
|
||
|
printf("ready for reading\n");
|
||
|
if (FD_ISSET(sock, &errorfs))
|
||
|
printf("has error\n");
|
||
|
recvpacket(sock, 0,
|
||
|
siocgstamp,
|
||
|
siocgstampns);
|
||
|
recvpacket(sock, MSG_ERRQUEUE,
|
||
|
siocgstamp,
|
||
|
siocgstampns);
|
||
|
}
|
||
|
} else {
|
||
|
/* write one packet */
|
||
|
sendpacket(sock,
|
||
|
(struct sockaddr *)&addr,
|
||
|
sizeof(addr));
|
||
|
next.tv_sec += 5;
|
||
|
continue;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|