ref: 45e2b4dfe9570aefe3e5f2a8b7af956b7365f522
dir: /sys/src/cmd/dial/at.c/
#include <u.h> #include <libc.h> void usage(void) { fprint(2, "usage: %s [-q] [-t seconds] command\n", argv0); exits("usage"); } struct { char *resp; int ok; } tab[] = { { "ok", 1 }, { "connect", 1 }, { "no carrier", 0 }, { "no dialtone", 0 }, { "error", 0 }, { "busy", 0 }, { "no answer", 0 }, { "delayed", 0 }, { "blacklisted", 0 }, }; int writewithoutcr(int fd, char *p, int i) { char *q, *e; /* dump cr's */ for(e = p+i; p < e; ){ q = memchr(p, '\r', e-p); if(q == nil) break; if(q > p) if(write(fd, p, q-p) < 0) return -1; p = q+1; } if(p < e) if(write(fd, p, e-p) < 0) return -1; return i; } int readln(int fd, char *buf, int n) { int c, i, sofar; sofar = 0; buf[sofar] = 0; while(sofar < n-1){ i = read(fd, buf+sofar, 1); if(i <= 0) return i; c = buf[sofar]; if(c == '\r') continue; sofar++; if(c == '\n') break; } buf[sofar] = 0; return sofar; } void docmd(char *cmd, int timeout, int quiet, int consfd) { char buf[4096]; int i; char *p, *cp; if(timeout == 0){ if(*cmd == 'd' || *cmd == 'D') timeout = 2*60; else timeout = 5; } p = smprint("at%s\r", cmd); for(cp = p; *cp; cp++){ write(1, cp, 1); sleep(100); } free(p); alarm(timeout*1000); for(;;){ i = readln(0, buf, sizeof(buf)); if(i <= 0){ rerrstr(buf, sizeof buf); exits(buf); } if(!quiet) writewithoutcr(consfd, buf, i); for(i = 0; i < nelem(tab); i++) if(cistrstr(buf, tab[i].resp)){ if(tab[i].ok) goto out; else exits(buf); } } out: alarm(0); } void main(int argc, char **argv) { int timeout; int quiet; int i; int consfd; timeout = 0; quiet = 0; ARGBEGIN { case 't': timeout = atoi(EARGF(usage())); break; case 'q': quiet = 1; break; default: usage(); } ARGEND; if(argc < 1) usage(); consfd = open("/dev/cons", ORDWR); if(consfd < 0) sysfatal("opening /dev/cons: %r"); for(i = 0; i < argc; i++) docmd(argv[i], timeout, quiet, consfd); exits(0); }