1 /* $NetBSD: tstp.c,v 1.11 1997/11/13 00:40:27 phil Exp $ */ 2 3 /* 4 * Copyright (c) 1981, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. 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 <sys/cdefs.h> 37 #ifndef lint 38 #if 0 39 static char sccsid[] = "@(#)tstp.c 8.3 (Berkeley) 5/4/94"; 40 #else 41 __RCSID("$NetBSD: tstp.c,v 1.11 1997/11/13 00:40:27 phil Exp $"); 42 #endif 43 #endif /* not lint */ 44 45 #include <errno.h> 46 #include <signal.h> 47 #include <termios.h> 48 #include <unistd.h> 49 50 #include "curses.h" 51 52 /* 53 * stop_signal_handler -- 54 * Handle stop signals. 55 */ 56 void 57 __stop_signal_handler(signo) 58 int signo; 59 { 60 sigset_t oset, set; 61 62 /* 63 * Block window change and timer signals. The latter is because 64 * applications use timers to decide when to repaint the screen. 65 */ 66 (void)sigemptyset(&set); 67 (void)sigaddset(&set, SIGALRM); 68 (void)sigaddset(&set, SIGWINCH); 69 (void)sigprocmask(SIG_BLOCK, &set, &oset); 70 71 /* 72 * End the window, which also resets the terminal state to the 73 * original modes. 74 */ 75 __stopwin(); 76 77 /* Unblock SIGTSTP. */ 78 (void)sigemptyset(&set); 79 (void)sigaddset(&set, SIGTSTP); 80 (void)sigprocmask(SIG_UNBLOCK, &set, NULL); 81 82 /* Stop ourselves. */ 83 (void)kill(0, SIGTSTP); 84 85 /* Time passes ... */ 86 87 /* restart things */ 88 __restartwin(); 89 90 /* Reset the signals. */ 91 (void)sigprocmask(SIG_SETMASK, &oset, NULL); 92 } 93 94 static void (*otstpfn) __P((int)) = SIG_DFL; 95 96 /* 97 * Set the TSTP handler. 98 */ 99 void 100 __set_stophandler() 101 { 102 otstpfn = signal(SIGTSTP, __stop_signal_handler); 103 } 104 105 /* 106 * Restore the TSTP handler. 107 */ 108 void 109 __restore_stophandler() 110 { 111 (void)signal(SIGTSTP, otstpfn); 112 } 113 114 115 /* To allow both SIGTSTP and endwin() to come back nicely, we provide 116 the following routines. */ 117 118 static struct termios save_termios; 119 120 int 121 __stopwin() 122 { 123 /* Get the current terminal state (which the user may have changed). */ 124 (void)tcgetattr(STDIN_FILENO, &save_termios); 125 126 __restore_stophandler(); 127 128 if (curscr != NULL) { 129 if (curscr->flags & __WSTANDOUT) { 130 tputs(SE, 0, __cputchar); 131 curscr->flags &= ~__WSTANDOUT; 132 } 133 __mvcur(curscr->cury, curscr->cury, curscr->maxy - 1, 0, 0); 134 } 135 136 (void)tputs(VE, 0, __cputchar); 137 (void)tputs(TE, 0, __cputchar); 138 (void)fflush(stdout); 139 (void)setvbuf(stdout, NULL, _IOLBF, 0); 140 141 return (tcsetattr(STDIN_FILENO, __tcaction ? 142 TCSASOFT | TCSADRAIN : TCSADRAIN, &__orig_termios) ? ERR : OK); 143 } 144 145 146 void 147 __restartwin() 148 { 149 /* Reset the curses SIGTSTP signal handler. */ 150 __set_stophandler(); 151 152 /* save the new "default" terminal state */ 153 (void)tcgetattr(STDIN_FILENO, &__orig_termios); 154 155 /* Reset the terminal state to the mode just before we stopped. */ 156 (void)tcsetattr(STDIN_FILENO, __tcaction ? 157 TCSASOFT | TCSADRAIN : TCSADRAIN, &save_termios); 158 159 /* Restart the screen. */ 160 __startwin(); 161 162 /* Repaint the screen. */ 163 wrefresh(curscr); 164 } 165