/* $NetBSD: awaitkey.c,v 1.1 2013/01/21 11:58:12 tsutsui Exp $ */ /*- * Copyright (c) 2013 Izumi Tsutsui. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include #include static void print_countdown(const char *, int); #define FMTLEN 40 static void print_countdown(const char *pfmt, int n) { int len, i; char fmtbuf[FMTLEN]; len = snprintf(fmtbuf, FMTLEN, pfmt, n); printf("%s", fmtbuf); for (i = 0; i < len; i++) putchar('\b'); } /* * awaitkey(const char *pfmt, int timeout, bool tell) * * Wait timeout seconds until any input from stdin. * print countdown message using "pfmt" if tell is true. * Requires tgetchar(), which returns 0 if there is no input. */ char awaitkey(const char *pfmt, int timeout, bool tell) { uint32_t otick; char c = 0; if (timeout <= 0) goto out; if (tell) print_countdown(pfmt, timeout); otick = tick; for (;;) { c = tgetchar(); if (c != 0) break; if (tick - otick >= hz) { otick = tick; if (--timeout == 0) break; if (tell) print_countdown(pfmt, timeout); } } out: if (tell) { printf(pfmt, 0); printf("\n"); } return c; }