2 * Copyright (C) 1984-2015 Mark Nudelman
4 * You may distribute under the terms of either the GNU General Public
5 * License or the Less License, as specified in the README file.
7 * For more information, see the README file.
13 * Routines dealing with signals.
15 * A signal usually merely causes a bit to be set in the "signals" word.
16 * At some convenient time, the mainline code checks to see if any
17 * signals need processing by calling psignal().
18 * If we happen to be reading from a file [in iread()] at the time
19 * the signal is received, we call intread to interrupt the iread.
26 * "sigs" contains bits indicating signals which need to be processed.
30 extern int sc_width, sc_height;
31 extern int screen_trashed;
36 extern int quit_on_intr;
37 extern int less_is_more;
38 extern long jump_sline_fraction;
41 * Interrupt signal handler.
49 LSIGNAL(SIGINT, SIG_ACK);
51 LSIGNAL(SIGINT, u_interrupt);
53 #if MSDOS_COMPILER==DJGPPC
55 * If a keyboard has been hit, it must be Ctrl-C
56 * (as opposed to Ctrl-Break), so consume it.
57 * (Otherwise, Less will beep when it sees Ctrl-C from keyboard.)
65 intread(); /* May longjmp */
70 * "Stop" (^Z) signal handler.
76 LSIGNAL(SIGTSTP, stop);
85 * "Window" change handler
91 LSIGNAL(SIGWINCH, winch);
99 * "Window" change handler
105 LSIGNAL(SIGWIND, winch);
113 #if MSDOS_COMPILER==WIN32C
115 * Handle CTRL-C and CTRL-BREAK keys.
120 wbreak_handler(DWORD dwCtrlType)
125 case CTRL_BREAK_EVENT:
136 * Set up the signal handlers.
144 * Set signal handlers.
146 (void) LSIGNAL(SIGINT, u_interrupt);
147 #if MSDOS_COMPILER==WIN32C
148 SetConsoleCtrlHandler(wbreak_handler, TRUE);
151 (void) LSIGNAL(SIGTSTP, stop);
154 (void) LSIGNAL(SIGWINCH, winch);
157 (void) LSIGNAL(SIGWIND, winch);
160 (void) LSIGNAL(SIGQUIT, SIG_IGN);
165 * Restore signals to defaults.
167 (void) LSIGNAL(SIGINT, SIG_DFL);
168 #if MSDOS_COMPILER==WIN32C
169 SetConsoleCtrlHandler(wbreak_handler, FALSE);
172 (void) LSIGNAL(SIGTSTP, SIG_DFL);
175 (void) LSIGNAL(SIGWINCH, SIG_IGN);
178 (void) LSIGNAL(SIGWIND, SIG_IGN);
181 (void) LSIGNAL(SIGQUIT, SIG_DFL);
187 * Process any signals we have received.
188 * A received signal cause a bit to be set in "sigs".
195 if ((tsignals = sigs) == 0)
200 if (tsignals & S_STOP)
203 * Clean up the terminal.
206 LSIGNAL(SIGTTOU, SIG_IGN);
213 LSIGNAL(SIGTTOU, SIG_DFL);
215 LSIGNAL(SIGTSTP, SIG_DFL);
216 kill(getpid(), SIGTSTP);
219 * Hopefully we'll be back later and resume here...
220 * Reset the terminal and arrange to repaint the
221 * screen when we get back to the main command loop.
223 LSIGNAL(SIGTSTP, stop);
231 if (tsignals & S_WINCH)
233 int old_width, old_height;
235 * Re-execute scrsize() to read the new window size.
237 old_width = sc_width;
238 old_height = sc_height;
240 if (sc_width != old_width || sc_height != old_height)
242 wscroll = (sc_height + 1) / 2;
249 if (tsignals & S_INTERRUPT)
252 quit(QUIT_INTERRUPT);