[116] | 1 | /**
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| 2 | * Rick van der Zwet <info@rickvanderzwet.nl>
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| 3 | * Licence: BSD
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| 4 | */
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| 5 |
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| 6 | #include "timediff.h"
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| 7 | #include <errno.h>
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| 8 |
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| 9 | void diep(char *s)
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| 10 | {
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| 11 | perror(s);
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| 12 | exit(1);
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| 13 | }
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| 14 |
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| 15 | int main(int argc, char * argv[]) {
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| 16 | printf("Size of .. : %li\n", sizeof(uint32_t));
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| 17 | printf("Size of .. : %li\n", sizeof(struct timeval_t));
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| 18 | printf("Size of .. : %li\n", sizeof(struct timeval));
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| 19 | struct timeval tv, tv2, tv3, tv4, tv_delta, tv_delta_system;
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| 20 | struct tm *tm, *tm2;
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| 21 | struct timeval_t packet;
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| 22 | gettimeofday(&tv, NULL);
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| 23 | tm=localtime(&tv.tv_sec);
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| 24 | printf("Started at: %d:%02d:%02d.%li \n", tm->tm_hour, tm->tm_min, tm->tm_sec, tv.tv_usec);
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| 25 |
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| 26 | struct sockaddr_in si_other, si_me;
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| 27 | int s, r, i, slen=sizeof(si_other);
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| 28 | char buf[BUFLEN];
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| 29 |
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| 30 | /* Set up receiving socket */
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| 31 | if ((r=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1)
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| 32 | diep("socket");
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| 33 |
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| 34 | memset((char *) &si_me, 0, sizeof(si_me));
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| 35 | si_me.sin_family = AF_INET;
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| 36 | si_me.sin_port = htons(PORT_CLIENT);
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| 37 | si_me.sin_addr.s_addr = htonl(INADDR_ANY);
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| 38 | if (bind(r, (struct sockaddr *)&si_me, sizeof(si_me))==-1)
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| 39 | diep("bind");
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| 40 |
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| 41 | if ((r=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1)
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| 42 | diep("socket");
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| 43 |
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| 44 | /* Prepare server connection */
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| 45 | memset((char *) &si_other, 0, sizeof(si_other));
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| 46 | si_other.sin_family = AF_INET;
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| 47 | si_other.sin_port = htons(PORT);
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| 48 | if (inet_aton(SRV_IP, &si_other.sin_addr)==0) {
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| 49 | fprintf(stderr, "inet_aton() failed\n");
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| 50 | exit(1);
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| 51 | }
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| 52 |
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| 53 | if ((s=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1)
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| 54 | diep("socket");
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| 55 |
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| 56 | /* We don't care in slow packets anymore */
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| 57 | struct timeval tv_timeout;
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| 58 | tv_timeout.tv_sec = 1L;
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| 59 | tv_timeout.tv_usec = 0L;
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| 60 | if (setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, &tv_timeout, sizeof(tv_timeout)) != 0)
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| 61 | diep("setsockopt");
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| 62 |
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| 63 |
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| 64 | for (i=0; i<NPACK; i++) {
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| 65 | printf("Sending packet %d and waiting for response\n", i);
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| 66 | gettimeofday(&tv, NULL);
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| 67 | packet.tv_sec = tv.tv_sec;
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| 68 | packet.tv_usec = tv.tv_usec;
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| 69 | if (sendto(s, (const void *)&packet, sizeof(packet), 0, (struct sockaddr *)&si_other, slen)==-1)
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| 70 | diep("sendto()");
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| 71 |
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| 72 | /* This will be generated more and less the same time as on the target side */
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| 73 | gettimeofday(&tv3, NULL);
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| 74 |
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| 75 | packet.tv_usec = 0;
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| 76 | packet.tv_sec = 0;
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| 77 |
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| 78 | if (recv(s, &packet, sizeof(packet), 0)==-1) {
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| 79 | if (errno == EAGAIN) {
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| 80 | perror("ERROR: No response received in time");
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| 81 | continue;
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| 82 | } else {
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| 83 | diep("recvfrom()");
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| 84 | }
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| 85 | }
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| 86 | gettimeofday(&tv4, NULL);
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| 87 | tv2.tv_sec = packet.tv_sec;
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| 88 | tv2.tv_usec = packet.tv_usec;
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| 89 |
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| 90 | printf("Received %li bytes\n", sizeof(packet));
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| 91 |
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| 92 | /* Display and calculations */
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| 93 | tm=localtime(&tv.tv_sec);
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| 94 | tm2=localtime(&tv2.tv_sec);
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| 95 | printf("Send timestamp: %d:%02d:%02d.%06li \n", tm->tm_hour, tm->tm_min, tm->tm_sec, tv.tv_usec);
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| 96 | printf("Received timestamp: %d:%02d:%02d.%06li \n", tm2->tm_hour, tm2->tm_min, tm2->tm_sec, tv2.tv_usec);
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| 97 |
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| 98 | tv_delta.tv_sec = tv4.tv_sec - tv.tv_sec;
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| 99 | tv_delta.tv_usec = tv4.tv_usec - tv.tv_usec;
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| 100 | printf("Time delta at local system (including transmit/receive): %02d.%06li\n",
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| 101 | (int)(tv_delta.tv_sec), tv_delta.tv_usec);
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| 102 |
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| 103 | tv_delta_system.tv_sec = (tv2.tv_sec - tv.tv_sec) - tv_delta.tv_sec / 2;
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| 104 | tv_delta_system.tv_usec = (tv2.tv_usec - tv.tv_usec) - tv_delta.tv_usec / 2;
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| 105 | printf("Time delta between sender and target: %02d.%06li\n",
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| 106 | (int)(tv_delta_system.tv_sec), tv_delta_system.tv_usec);
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| 107 | printf("\n");
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| 108 | }
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| 109 |
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| 110 | close(s);
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| 111 | return 0;
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| 112 |
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| 113 | exit(0);
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| 114 | }
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