1 /* 2 * Copyright (c) 1981, 1993, 1994 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 */ 7 8 #ifndef lint 9 static char sccsid[] = "@(#)tstp.c 8.3 (Berkeley) 05/04/94"; 10 #endif /* not lint */ 11 12 #include <errno.h> 13 #include <signal.h> 14 #include <termios.h> 15 #include <unistd.h> 16 17 #include "curses.h" 18 19 /* 20 * stop_signal_handler -- 21 * Handle stop signals. 22 */ 23 void 24 __stop_signal_handler(signo) 25 int signo; 26 { 27 struct termios save; 28 sigset_t oset, set; 29 30 /* Get the current terminal state (which the user may have changed). */ 31 if (tcgetattr(STDIN_FILENO, &save)) 32 return; 33 34 /* 35 * Block window change and timer signals. The latter is because 36 * applications use timers to decide when to repaint the screen. 37 */ 38 (void)sigemptyset(&set); 39 (void)sigaddset(&set, SIGALRM); 40 (void)sigaddset(&set, SIGWINCH); 41 (void)sigprocmask(SIG_BLOCK, &set, &oset); 42 43 /* 44 * End the window, which also resets the terminal state to the 45 * original modes. 46 */ 47 endwin(); 48 49 /* Unblock SIGTSTP. */ 50 (void)sigemptyset(&set); 51 (void)sigaddset(&set, SIGTSTP); 52 (void)sigprocmask(SIG_UNBLOCK, &set, NULL); 53 54 /* Stop ourselves. */ 55 __restore_stophandler(); 56 (void)kill(0, SIGTSTP); 57 58 /* Time passes ... */ 59 60 /* Reset the curses SIGTSTP signal handler. */ 61 __set_stophandler(); 62 63 /* save the new "default" terminal state */ 64 (void)tcgetattr(STDIN_FILENO, &__orig_termios); 65 66 /* Reset the terminal state to the mode just before we stopped. */ 67 (void)tcsetattr(STDIN_FILENO, __tcaction ? 68 TCSASOFT | TCSADRAIN : TCSADRAIN, &save); 69 70 /* Restart the screen. */ 71 __startwin(); 72 73 /* Repaint the screen. */ 74 wrefresh(curscr); 75 76 /* Reset the signals. */ 77 (void)sigprocmask(SIG_SETMASK, &oset, NULL); 78 } 79 80 static void (*otstpfn)() = SIG_DFL; 81 82 /* 83 * Set the TSTP handler. 84 */ 85 void 86 __set_stophandler() 87 { 88 otstpfn = signal(SIGTSTP, __stop_signal_handler); 89 } 90 91 /* 92 * Restore the TSTP handler. 93 */ 94 void 95 __restore_stophandler() 96 { 97 (void)signal(SIGTSTP, otstpfn); 98 } 99