1 /* 2 * Copyright (c) 1983, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Edward Wang at The University of California, Berkeley. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)wwrint.c 8.1 (Berkeley) 6/6/93 37 * $FreeBSD: src/usr.bin/window/wwrint.c,v 1.1.1.1.14.1 2001/05/17 09:45:01 obrien Exp $ 38 * $DragonFly: src/usr.bin/window/wwrint.c,v 1.2 2003/06/17 04:29:34 dillon Exp $ 39 */ 40 41 #include "ww.h" 42 #include "tt.h" 43 #if defined(OLD_TTY) || defined(VMIN_BUG) 44 #include <fcntl.h> 45 #endif 46 47 /* 48 * Tty input interrupt handler. 49 * (1) Read input into buffer (wwib*). 50 * (2) Set the interrupt flag if anything is read. 51 * Currently, the last is used to get out of the blocking 52 * select() in wwiomux(). 53 * To avoid race conditions, we only modify wwibq in here, except 54 * when the buffer is empty; and everywhere else, we only change wwibp. 55 * It should be completely safe. 56 */ 57 void 58 wwrint() 59 { 60 register n; 61 62 if (wwibp == wwibq) 63 wwibp = wwibq = wwib; 64 wwnread++; 65 #if defined(OLD_TTY) || defined(VMIN_BUG) 66 /* we have set c_cc[VMIN] to 0 */ 67 (void) fcntl(0, F_SETFL, O_NONBLOCK|wwnewtty.ww_fflags); 68 #endif 69 n = read(0, wwibq, wwibe - wwibq); 70 #if defined(OLD_TTY) || defined(VMIN_BUG) 71 (void) fcntl(0, F_SETFL, wwnewtty.ww_fflags); 72 #endif 73 if (n > 0) { 74 if (tt.tt_rint) 75 n = (*tt.tt_rint)(wwibq, n); 76 if (n > 0) { 77 wwibq += n; 78 wwnreadc += n; 79 /* 80 * Hasten or delay the next checkpoint, 81 * as the case may be. 82 */ 83 if (tt.tt_checkpoint && !wwdocheckpoint) 84 (void) alarm(1); 85 wwsetintr(); 86 } 87 } else if (n == 0) 88 wwnreadz++; 89 else 90 wwnreade++; 91 } 92