1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
/* signals.c -- Install and maintain Info signal handlers. */
/* This file is part of GNU Info, a program for reading online documentation
stored in Info format.
Copyright (C) 1993, 1994, 1995 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
Written by Brian Fox (bfox@ai.mit.edu). */
#include "info.h"
#include "signals.h"
/* **************************************************************** */
/* */
/* Pretending That We Have POSIX Signals */
/* */
/* **************************************************************** */
#if !defined (HAVE_SIGPROCMASK) && defined (HAVE_SIGSETMASK)
/* Perform OPERATION on NEWSET, perhaps leaving information in OLDSET. */
static void
sigprocmask (operation, newset, oldset)
int operation, *newset, *oldset;
{
switch (operation)
{
case SIG_UNBLOCK:
sigsetmask (sigblock (0) & ~(*newset));
break;
case SIG_BLOCK:
*oldset = sigblock (*newset);
break;
case SIG_SETMASK:
sigsetmask (*newset);
break;
default:
abort ();
}
}
#endif /* !HAVE_SIGPROCMASK && HAVE_SIGSETMASK */
/* **************************************************************** */
/* */
/* Signal Handling for Info */
/* */
/* **************************************************************** */
typedef RETSIGTYPE signal_handler ();
static RETSIGTYPE info_signal_handler ();
static signal_handler *old_TSTP, *old_TTOU, *old_TTIN;
static signal_handler *old_WINCH, *old_INT;
void
initialize_info_signal_handler ()
{
#if defined (SIGTSTP)
old_TSTP = (signal_handler *) signal (SIGTSTP, info_signal_handler);
old_TTOU = (signal_handler *) signal (SIGTTOU, info_signal_handler);
old_TTIN = (signal_handler *) signal (SIGTTIN, info_signal_handler);
#endif /* SIGTSTP */
#if defined (SIGWINCH)
old_WINCH = (signal_handler *) signal (SIGWINCH, info_signal_handler);
#endif
#if defined (SIGINT)
old_INT = (signal_handler *) signal (SIGINT, info_signal_handler);
#endif
}
static void
redisplay_after_signal ()
{
terminal_clear_screen ();
display_clear_display (the_display);
window_mark_chain (windows, W_UpdateWindow);
display_update_display (windows);
display_cursor_at_point (active_window);
fflush (stdout);
}
static RETSIGTYPE
info_signal_handler (sig)
int sig;
{
signal_handler **old_signal_handler;
switch (sig)
{
#if defined (SIGTSTP)
case SIGTSTP:
case SIGTTOU:
case SIGTTIN:
#endif
#if defined (SIGINT)
case SIGINT:
#endif
{
#if defined (SIGTSTP)
if (sig == SIGTSTP)
old_signal_handler = &old_TSTP;
if (sig == SIGTTOU)
old_signal_handler = &old_TTOU;
if (sig == SIGTTIN)
old_signal_handler = &old_TTIN;
#endif /* SIGTSTP */
if (sig == SIGINT)
old_signal_handler = &old_INT;
/* For stop signals, restore the terminal IO, leave the cursor
at the bottom of the window, and stop us. */
terminal_goto_xy (0, screenheight - 1);
terminal_clear_to_eol ();
fflush (stdout);
terminal_unprep_terminal ();
signal (sig, *old_signal_handler);
UNBLOCK_SIGNAL (sig);
kill (getpid (), sig);
/* The program is returning now. Restore our signal handler,
turn on terminal handling, redraw the screen, and place the
cursor where it belongs. */
terminal_prep_terminal ();
*old_signal_handler = (signal_handler *) signal (sig, info_signal_handler);
redisplay_after_signal ();
fflush (stdout);
}
break;
#if defined (SIGWINCH)
case SIGWINCH:
{
/* Turn off terminal IO, tell our parent that the window has changed,
then reinitialize the terminal and rebuild our windows. */
old_signal_handler = &old_WINCH;
terminal_goto_xy (0, 0);
fflush (stdout);
terminal_unprep_terminal ();
signal (sig, *old_signal_handler);
UNBLOCK_SIGNAL (sig);
kill (getpid (), sig);
/* After our old signal handler returns... */
terminal_get_screen_size ();
terminal_prep_terminal ();
display_initialize_display (screenwidth, screenheight);
window_new_screen_size (screenwidth, screenheight, (VFunction *)NULL);
*old_signal_handler = (signal_handler *) signal (sig, info_signal_handler);
redisplay_after_signal ();
}
break;
#endif /* SIGWINCH */
}
}
|
