FreeCalypso > hg > freecalypso-tools
view uptools/atcmd/atinterf.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 | f0e9bb28b4d6 |
children |
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/* * This module implements the interface functions to the AT command phone or * modem to be used by the rest of the FreeCalypso User Phone tools suite. */ #include <sys/types.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <strings.h> #include <unistd.h> #include "../../rvinterf/include/exitcodes.h" static char atinterf_pathname[] = "/opt/freecalypso/bin/fcup-atinterf"; static char rvtat_pathname[] = "/opt/freecalypso/bin/fcup-rvtat"; static char shell_pathname[] = "/bin/sh"; char *target_ttyport, *target_baud, *external_prog; int rvtat_mode, no_target_mode; static char *backend_prog, *backend_argv[6]; FILE *cpipeF, *rpipeF; char at_response[514]; atinterf_cmdline_opt(opt) { extern char *optarg; switch (opt) { case 'B': target_baud = optarg; return(1); case 'n': no_target_mode = 1; return(1); case 'p': target_ttyport = optarg; return(1); case 'R': rvtat_mode = 1; return(1); case 'X': external_prog = optarg; return(1); } return(0); } static void preen_port_baud_config() { if (!target_ttyport && target_baud) { fprintf(stderr, "error: -B option invalid without -p\n"); exit(ERROR_USAGE); } if (rvtat_mode) return; if (!target_ttyport) { target_ttyport = getenv("FC_GSM_DEVICE"); if (!target_ttyport) { fprintf(stderr, "error: no FC GSM device target specified\n"); exit(ERROR_USAGE); } } if (!target_baud) target_baud = "115200"; } static void setup_be_native_at() { backend_prog = atinterf_pathname; backend_argv[0] = "fcup-atinterf"; backend_argv[1] = target_ttyport; backend_argv[2] = target_baud; backend_argv[3] = 0; } static void setup_be_rvtat() { char **ap; backend_prog = rvtat_pathname; ap = backend_argv; *ap++ = "fcup-rvtat"; if (target_ttyport) { *ap++ = "-p"; *ap++ = target_ttyport; } if (target_baud) { *ap++ = "-B"; *ap++ = target_baud; } *ap = 0; } static void setup_be_external() { backend_prog = shell_pathname; backend_argv[0] = "sh"; backend_argv[1] = "-c"; backend_argv[2] = external_prog; backend_argv[3] = 0; } atinterf_init() { int cpipe[2], rpipe[2], rc; if (no_target_mode) return(0); if (external_prog) setup_be_external(); else { preen_port_baud_config(); if (rvtat_mode) setup_be_rvtat(); else setup_be_native_at(); } if (pipe(cpipe) < 0 || pipe(rpipe) < 0) { perror("pipe"); exit(ERROR_UNIX); } rc = vfork(); if (rc < 0) { perror("vfork for launching back end"); exit(ERROR_UNIX); } if (!rc) { /* we are in the child - prepare to exec the BE */ dup2(cpipe[0], 0); dup2(rpipe[1], 1); close(cpipe[0]); close(cpipe[1]); close(rpipe[0]); close(rpipe[1]); /* do the exec */ execv(backend_prog, backend_argv); perror(backend_prog); _exit(1); } close(cpipe[0]); close(rpipe[1]); cpipeF = fdopen(cpipe[1], "w"); if (!cpipeF) { perror("fdopen"); exit(ERROR_UNIX); } rpipeF = fdopen(rpipe[0], "r"); if (!rpipeF) { perror("fdopen"); exit(ERROR_UNIX); } return(0); } atinterf_exec_cmd(command, message, callback) char *command, *message; void (*callback)(); { char *nl; if (no_target_mode) { puts(command); if (message) puts(message); strcpy(at_response, "FOK"); return(0); } if (message) { fputs("c+m\n", cpipeF); fprintf(cpipeF, "%s\n", command); fprintf(cpipeF, "%s\n", message); } else fprintf(cpipeF, "%s\n", command); fflush(cpipeF); for (;;) { if (!fgets(at_response, sizeof at_response, rpipeF)) { fprintf(stderr, "error reading AT response from back end\n"); exit(ERROR_RVINTERF); } nl = index(at_response, '\n'); if (!nl) { fprintf(stderr, "error: back end response is too long or unterminated\n"); exit(ERROR_RVINTERF); } *nl = '\0'; switch (at_response[0]) { case 'E': fprintf(stderr, "error from back end: %s\n", at_response + 1); exit(ERROR_RVINTERF); case 'F': return(0); case 'I': if (callback) callback(); continue; } fprintf(stderr, "error: invalid response from back end\n"); exit(ERROR_RVINTERF); } } atinterf_exec_cmd_needok(command, message, callback) char *command, *message; void (*callback)(); { atinterf_exec_cmd(command, message, callback); if (strcmp(at_response+1, "OK")) { fprintf(stderr, "AT error: %s\n", at_response+1); exit(ERROR_TARGET); } return(0); }