FreeCalypso > hg > freecalypso-tools
view rvinterf/lowlevel/rvtdump.c @ 407:19e5a3e2f9c0
fcup-settime: moved time() retrieval a little closer to the output
A fundamental problem with all simple time transfer tools is that there is
always some delay between the time retrieval on the source system and that
transmitted time being set on the destination, and the resulting time
on the destination system is off by that delay amount. This delay cannot
be fully eliminated when working in a simple environment like ours,
but we should make our best effort to minimize it. In the present case,
moving the atinterf_init() call before the time() retrieval should make
a teensy-tiny improvement.
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Sat, 11 Aug 2018 21:52:17 +0000 |
parents | 6f078c4a5506 |
children |
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line source
/* * This program reads bytes from a serial port, parses them assuming * TI's RVT MUX format, and prints every decoded packet. */ #include <sys/types.h> #include <sys/errno.h> #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <time.h> #include "../include/pktmux.h" extern int target_fd; extern u_char rxpkt[]; extern size_t rxpkt_len; char *logfname; FILE *logF; time_t logtime; int background; int no_output; /* for output.c */ static char *baudrate = "115200"; static char keepalive_msg[] = "Received keepalive query, unable to respond, please run rvinterf"; main(argc, argv) char **argv; { extern char *optarg; extern int optind; int c; fd_set fds; while ((c = getopt(argc, argv, "bB:d:l:")) != EOF) switch (c) { case 'b': background++; no_output++; /* for output.c */ continue; case 'B': baudrate = optarg; continue; case 'd': target_fd = atoi(optarg); continue; case 'l': logfname = optarg; continue; case '?': default: usage: fprintf(stderr, "usage: %s [options] ttyport\n", argv[0]); exit(1); } if (background && !logfname) { fprintf(stderr, "%s: -b is meaningless without -l\n", argv[0]); exit(1); } if (target_fd <= 0) { if (argc - optind != 1) goto usage; open_serial_port(argv[optind]); set_fixed_baudrate(baudrate); } set_serial_nonblock(0); setlinebuf(stdout); if (logfname) { logF = fopen(logfname, "w"); if (!logF) { perror(logfname); exit(1); } setlinebuf(logF); fprintf(logF, "*** Log of decoded RVT output ***\n"); } if (background) { c = fork(); if (c < 0) { perror("fork"); exit(1); } if (c) { printf("rvtdump forked into background (pid %d)\n", c); exit(0); } } for (;;) { FD_ZERO(&fds); FD_SET(target_fd, &fds); c = select(target_fd+1, &fds, 0, 0, 0); time(&logtime); if (c < 0) { if (errno == EINTR) continue; perror("select"); exit(1); } if (FD_ISSET(target_fd, &fds)) process_serial_rx(); } } handle_rx_packet() { switch (rxpkt[0]) { case RVT_RV_HEADER: if (rxpkt_len < 6) goto unknown; print_rv_trace(); return; case RVT_L1_HEADER: print_l1_trace(); return; case RVT_L23_HEADER: print_g23_trace(); return; case RVT_TM_HEADER: print_tm_output_raw(); return; case RVT_AT_HEADER: print_ati_output(); return; case RVT_EXTUI_HEADER: if (rxpkt_len < 5 || !(rxpkt_len & 1)) goto unknown; report_extui_packet(); return; case RVT_TCH_HEADER: print_tch_output_raw(); return; case RVT_KEEPALIVE_HEADER: if (rxpkt_len != 2 || rxpkt[1] != 'Q') goto unknown; output_line(keepalive_msg); return; case '*': print_fc_lld_msg(); return; default: unknown: print_unknown_packet(); } }