1/*
2    SDL - Simple DirectMedia Layer
3    Copyright (C) 1997-2012 Sam Lantinga
4
5    This library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9
10    This library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14
15    You should have received a copy of the GNU Lesser General Public
16    License along with this library; if not, write to the Free Software
17    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
18
19    Sam Lantinga
20    slouken@libsdl.org
21*/
22#include "SDL_config.h"
23
24/* General fatal signal handling code for SDL */
25
26#ifdef HAVE_SIGNAL_H
27
28#include <signal.h>
29
30#include "SDL.h"
31#include "SDL_fatal.h"
32
33/* This installs some signal handlers for the more common fatal signals,
34   so that if the programmer is lazy, the app doesn't die so horribly if
35   the program crashes.
36*/
37
38static void SDL_Parachute(int sig)
39{
40	signal(sig, SIG_DFL);
41	SDL_Quit();
42	raise(sig);
43}
44
45static int SDL_fatal_signals[] = {
46	SIGSEGV,
47#ifdef SIGBUS
48	SIGBUS,
49#endif
50#ifdef SIGFPE
51	SIGFPE,
52#endif
53#ifdef SIGQUIT
54	SIGQUIT,
55#endif
56	0
57};
58
59void SDL_InstallParachute(void)
60{
61	/* Set a handler for any fatal signal not already handled */
62	int i;
63#ifdef HAVE_SIGACTION
64	struct sigaction action;
65
66	for ( i=0; SDL_fatal_signals[i]; ++i ) {
67		sigaction(SDL_fatal_signals[i], NULL, &action);
68		if ( action.sa_handler == SIG_DFL ) {
69			action.sa_handler = SDL_Parachute;
70			sigaction(SDL_fatal_signals[i], &action, NULL);
71		}
72	}
73#ifdef SIGALRM
74	/* Set SIGALRM to be ignored -- necessary on Solaris */
75	sigaction(SIGALRM, NULL, &action);
76	if ( action.sa_handler == SIG_DFL ) {
77		action.sa_handler = SIG_IGN;
78		sigaction(SIGALRM, &action, NULL);
79	}
80#endif
81#else
82	void (*ohandler)(int);
83
84	for ( i=0; SDL_fatal_signals[i]; ++i ) {
85		ohandler = signal(SDL_fatal_signals[i], SDL_Parachute);
86		if ( ohandler != SIG_DFL ) {
87			signal(SDL_fatal_signals[i], ohandler);
88		}
89	}
90#endif /* HAVE_SIGACTION */
91	return;
92}
93
94void SDL_UninstallParachute(void)
95{
96	/* Remove a handler for any fatal signal handled */
97	int i;
98#ifdef HAVE_SIGACTION
99	struct sigaction action;
100
101	for ( i=0; SDL_fatal_signals[i]; ++i ) {
102		sigaction(SDL_fatal_signals[i], NULL, &action);
103		if ( action.sa_handler == SDL_Parachute ) {
104			action.sa_handler = SIG_DFL;
105			sigaction(SDL_fatal_signals[i], &action, NULL);
106		}
107	}
108#else
109	void (*ohandler)(int);
110
111	for ( i=0; SDL_fatal_signals[i]; ++i ) {
112		ohandler = signal(SDL_fatal_signals[i], SIG_DFL);
113		if ( ohandler != SDL_Parachute ) {
114			signal(SDL_fatal_signals[i], ohandler);
115		}
116	}
117#endif /* HAVE_SIGACTION */
118}
119
120#else
121
122/* No signals on this platform, nothing to do.. */
123
124void SDL_InstallParachute(void)
125{
126	return;
127}
128
129void SDL_UninstallParachute(void)
130{
131	return;
132}
133
134#endif /* HAVE_SIGNAL_H */
135