1 /* @(#)wwrint.c 8.1 (Berkeley) 6/6/93 */ 2 /* $NetBSD: wwrint.c,v 1.7 2003/08/07 11:17:44 agc Exp $ */ 3 4 /* 5 * Copyright (c) 1983, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Edward Wang at The University of California, Berkeley. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <unistd.h> 37 #include "ww.h" 38 #include "tt.h" 39 40 /* 41 * Tty input interrupt handler. 42 * (1) Read input into buffer (wwib*). 43 * (2) Set the interrupt flag if anything is read. 44 * Currently, the last is used to get out of the blocking 45 * select() in wwiomux(). 46 * To avoid race conditions, we only modify wwibq in here, except 47 * when the buffer is empty; and everywhere else, we only change wwibp. 48 * It should be completely safe. 49 */ 50 void 51 wwrint(void) 52 { 53 int n; 54 55 wwnread++; 56 n = read(0, wwibq, wwibe - wwibq); 57 if (n > 0) { 58 if (tt.tt_rint) 59 n = (*tt.tt_rint)(wwibq, n); 60 if (n > 0) { 61 wwibq += n; 62 wwnreadc += n; 63 /* 64 * Hasten or delay the next checkpoint, 65 * as the case may be. 66 */ 67 if (tt.tt_checkpoint && !wwdocheckpoint) 68 (void) alarm(1); 69 wwsetintr(); 70 } 71 } else if (n == 0) 72 wwnreadz++; 73 else 74 wwnreade++; 75 } 76