Commit | Line | Data |
---|---|---|
bfe13c81 KB |
1 | /* |
2 | * Copyright (c) 1988 Mark Nudleman | |
3 | * Copyright (c) 1988 Regents of the University of California. | |
4 | * All rights reserved. | |
5 | * | |
bfe13c81 KB |
6 | * Redistribution and use in source and binary forms are permitted |
7 | * provided that the above copyright notice and this paragraph are | |
8 | * duplicated in all such forms and that any documentation, | |
9 | * advertising materials, and other materials related to such | |
10 | * distribution and use acknowledge that the software was developed | |
a942b40b KB |
11 | * by Mark Nudleman and the University of California, Berkeley. The |
12 | * name of Mark Nudleman or the | |
bfe13c81 KB |
13 | * University may not be used to endorse or promote products derived |
14 | * from this software without specific prior written permission. | |
15 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR | |
16 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED | |
17 | * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. | |
18 | */ | |
19 | ||
20 | #ifndef lint | |
966c6ec0 | 21 | static char sccsid[] = "@(#)signal.c 5.5 (Berkeley) %G%"; |
bfe13c81 KB |
22 | #endif /* not lint */ |
23 | ||
24 | /* | |
25 | * Routines dealing with signals. | |
26 | * | |
27 | * A signal usually merely causes a bit to be set in the "signals" word. | |
28 | * At some convenient time, the mainline code checks to see if any | |
29 | * signals need processing by calling psignal(). | |
30 | * If we happen to be reading from a file [in iread()] at the time | |
31 | * the signal is received, we call intread to interrupt the iread. | |
32 | */ | |
33 | ||
966c6ec0 | 34 | #include <less.h> |
bfe13c81 KB |
35 | #include <signal.h> |
36 | ||
37 | /* | |
38 | * "sigs" contains bits indicating signals which need to be processed. | |
39 | */ | |
966c6ec0 | 40 | int sigs; |
bfe13c81 | 41 | |
bfe13c81 KB |
42 | #ifdef SIGTSTP |
43 | #define S_STOP 02 | |
44 | #endif | |
45 | #if defined(SIGWINCH) || defined(SIGWIND) | |
46 | #define S_WINCH 04 | |
47 | #endif | |
48 | ||
49 | extern int sc_width, sc_height; | |
50 | extern int screen_trashed; | |
51 | extern int lnloop; | |
52 | extern int linenums; | |
53 | extern int scroll; | |
54 | extern int reading; | |
55 | ||
bfe13c81 KB |
56 | #ifdef SIGTSTP |
57 | /* | |
58 | * "Stop" (^Z) signal handler. | |
59 | */ | |
966c6ec0 | 60 | static |
bfe13c81 KB |
61 | stop() |
62 | { | |
966c6ec0 | 63 | (void)signal(SIGTSTP, stop); |
bfe13c81 KB |
64 | sigs |= S_STOP; |
65 | if (reading) | |
66 | intread(); | |
67 | } | |
68 | #endif | |
69 | ||
70 | #ifdef SIGWINCH | |
71 | /* | |
72 | * "Window" change handler | |
73 | */ | |
bfe13c81 KB |
74 | winch() |
75 | { | |
966c6ec0 | 76 | (void)signal(SIGWINCH, winch); |
bfe13c81 KB |
77 | sigs |= S_WINCH; |
78 | if (reading) | |
79 | intread(); | |
80 | } | |
81 | #else | |
82 | #ifdef SIGWIND | |
83 | /* | |
84 | * "Window" change handler | |
85 | */ | |
bfe13c81 KB |
86 | winch() |
87 | { | |
966c6ec0 | 88 | (void)signal(SIGWIND, winch); |
bfe13c81 KB |
89 | sigs |= S_WINCH; |
90 | if (reading) | |
91 | intread(); | |
92 | } | |
93 | #endif | |
94 | #endif | |
95 | ||
96 | /* | |
97 | * Set up the signal handlers. | |
98 | */ | |
bfe13c81 KB |
99 | init_signals(on) |
100 | int on; | |
101 | { | |
966c6ec0 KB |
102 | int quit(); |
103 | ||
bfe13c81 KB |
104 | if (on) |
105 | { | |
106 | /* | |
107 | * Set signal handlers. | |
108 | */ | |
966c6ec0 | 109 | (void)signal(SIGINT, quit); |
bfe13c81 | 110 | #ifdef SIGTSTP |
966c6ec0 | 111 | (void)signal(SIGTSTP, stop); |
bfe13c81 KB |
112 | #endif |
113 | #ifdef SIGWINCH | |
966c6ec0 | 114 | (void)signal(SIGWINCH, winch); |
bfe13c81 KB |
115 | #else |
116 | #ifdef SIGWIND | |
966c6ec0 | 117 | (void)signal(SIGWIND, winch); |
bfe13c81 KB |
118 | #endif |
119 | #endif | |
120 | } else | |
121 | { | |
122 | /* | |
123 | * Restore signals to defaults. | |
124 | */ | |
966c6ec0 | 125 | (void)signal(SIGINT, SIG_DFL); |
bfe13c81 | 126 | #ifdef SIGTSTP |
966c6ec0 | 127 | (void)signal(SIGTSTP, SIG_DFL); |
bfe13c81 KB |
128 | #endif |
129 | #ifdef SIGWINCH | |
966c6ec0 | 130 | (void)signal(SIGWINCH, SIG_IGN); |
bfe13c81 KB |
131 | #endif |
132 | #ifdef SIGWIND | |
966c6ec0 | 133 | (void)signal(SIGWIND, SIG_IGN); |
bfe13c81 KB |
134 | #endif |
135 | } | |
136 | } | |
137 | ||
138 | /* | |
139 | * Process any signals we have received. | |
140 | * A received signal cause a bit to be set in "sigs". | |
141 | */ | |
bfe13c81 KB |
142 | psignals() |
143 | { | |
144 | register int tsignals; | |
145 | ||
146 | if ((tsignals = sigs) == 0) | |
9bf656f5 | 147 | return; |
bfe13c81 KB |
148 | sigs = 0; |
149 | ||
150 | #ifdef S_WINCH | |
151 | if (tsignals & S_WINCH) | |
152 | { | |
153 | int old_width, old_height; | |
154 | /* | |
155 | * Re-execute get_term() to read the new window size. | |
156 | */ | |
157 | old_width = sc_width; | |
158 | old_height = sc_height; | |
159 | get_term(); | |
160 | if (sc_width != old_width || sc_height != old_height) | |
161 | { | |
162 | scroll = (sc_height + 1) / 2; | |
163 | screen_trashed = 1; | |
164 | } | |
165 | } | |
166 | #endif | |
167 | #ifdef SIGTSTP | |
168 | if (tsignals & S_STOP) | |
169 | { | |
170 | /* | |
171 | * Clean up the terminal. | |
172 | */ | |
173 | #ifdef SIGTTOU | |
966c6ec0 | 174 | (void)signal(SIGTTOU, SIG_IGN); |
bfe13c81 KB |
175 | #endif |
176 | lower_left(); | |
177 | clear_eol(); | |
178 | deinit(); | |
966c6ec0 | 179 | (void)flush(); |
bfe13c81 KB |
180 | raw_mode(0); |
181 | #ifdef SIGTTOU | |
966c6ec0 | 182 | (void)signal(SIGTTOU, SIG_DFL); |
bfe13c81 | 183 | #endif |
966c6ec0 KB |
184 | (void)signal(SIGTSTP, SIG_DFL); |
185 | (void)kill(getpid(), SIGTSTP); | |
bfe13c81 KB |
186 | /* |
187 | * ... Bye bye. ... | |
188 | * Hopefully we'll be back later and resume here... | |
189 | * Reset the terminal and arrange to repaint the | |
190 | * screen when we get back to the main command loop. | |
191 | */ | |
966c6ec0 | 192 | (void)signal(SIGTSTP, stop); |
bfe13c81 KB |
193 | raw_mode(1); |
194 | init(); | |
195 | screen_trashed = 1; | |
196 | } | |
197 | #endif | |
bfe13c81 | 198 | } |