xref: /minix3/include/signal.h (revision 68db8ed0b9600e11489ca631e7ea24a6f5adb15f)
1 /* The <signal.h> header defines all the ANSI and POSIX signals.
2  * MINIX supports all the signals required by POSIX. They are defined below.
3  * Some additional signals are also supported.
4  */
5 
6 #ifndef _SIGNAL_H
7 #define _SIGNAL_H
8 
9 #ifndef _ANSI_H
10 #include <ansi.h>
11 #endif
12 #ifdef _POSIX_SOURCE
13 #ifndef _TYPES_H
14 #include <minix/types.h>
15 #endif
16 #endif
17 
18 /* Here are types that are closely associated with signal handling. */
19 typedef int sig_atomic_t;
20 
21 #ifdef _POSIX_SOURCE
22 #ifndef _SIGSET_T
23 #define _SIGSET_T
24 typedef unsigned long sigset_t;
25 #endif
26 #endif
27 
28 /* Regular signals. */
29 #define SIGHUP             1	/* hangup */
30 #define SIGINT             2	/* interrupt (DEL) */
31 #define SIGQUIT            3	/* quit (ASCII FS) */
32 #define SIGILL             4	/* illegal instruction */
33 #define SIGTRAP            5	/* trace trap (not reset when caught) */
34 #define SIGABRT            6	/* IOT instruction */
35 #define SIGBUS             7	/* bus error */
36 #define SIGFPE             8	/* floating point exception */
37 #define SIGKILL            9	/* kill (cannot be caught or ignored) */
38 #define SIGUSR1           10	/* user defined signal # 1 */
39 #define SIGSEGV           11	/* segmentation violation */
40 #define SIGUSR2           12	/* user defined signal # 2 */
41 #define SIGPIPE           13	/* write on a pipe with no one to read it */
42 #define SIGALRM           14	/* alarm clock */
43 #define SIGTERM           15	/* software termination signal from kill */
44 #define SIGEMT		  16	/* EMT instruction */
45 #define SIGCHLD           17	/* child process terminated or stopped */
46 #define SIGWINCH    	  21	/* window size has changed */
47 #define SIGVTALRM         24	/* virtual alarm */
48 #define SIGPROF           25	/* profiler alarm */
49 
50 /* POSIX requires the following signals to be defined, even if they are
51  * not supported.  Here are the definitions, but they are not supported.
52  */
53 #define SIGCONT           18	/* continue if stopped */
54 #define SIGSTOP           19	/* stop signal */
55 #define SIGTSTP           20	/* interactive stop signal */
56 #define SIGTTIN           22	/* background process wants to read */
57 #define SIGTTOU           23	/* background process wants to write */
58 
59 #define _NSIG             26	/* highest signal number plus one */
60 #define NSIG             _NSIG
61 
62 #ifdef _MINIX
63 #define SIGIOT             SIGABRT /* for people who speak PDP-11 */
64 
65 /* MINIX specific signals. These signals are not used by user proceses,
66  * but meant to inform system processes, like the PM, about system events.
67  * The order here determines the order signals are processed by system
68  * processes in user-space. Higher-priority signals should be first.
69  */
70 /* Signals delivered by a signal manager. */
71 #define SIGSNDELAY	  26	/* end of delay for signal delivery */
72 
73 #define SIGS_FIRST	  SIGHUP      /* first system signal */
74 #define SIGS_LAST	  SIGSNDELAY   /* last system signal */
75 #define IS_SIGS(signo)    (signo>=SIGS_FIRST && signo<=SIGS_LAST)
76 
77 /* Signals delivered by the kernel. */
78 #define SIGKMEM		  27	/* kernel memory request pending */
79 #define SIGKMESS   	  28	/* new kernel message */
80 #define SIGKSIGSM    	  29	/* kernel signal pending for signal manager */
81 #define SIGKSIG    	  30	/* kernel signal pending */
82 
83 #define SIGK_FIRST	  SIGKMEM      /* first kernel signal */
84 #define SIGK_LAST	  SIGKSIG     /* last kernel signal */
85 #define IS_SIGK(signo)    (signo>=SIGK_FIRST && signo<=SIGK_LAST)
86 
87 /* Termination signals for Minix system processes. */
88 #define SIGS_IS_LETHAL(sig) \
89     (sig == SIGILL || sig == SIGBUS || sig == SIGFPE || sig == SIGSEGV \
90     || sig == SIGEMT || sig == SIGABRT)
91 #define SIGS_IS_TERMINATION(sig) (SIGS_IS_LETHAL(sig) \
92     || (sig == SIGKILL || sig == SIGPIPE))
93 #define SIGS_IS_STACKTRACE(sig) (SIGS_IS_LETHAL(sig) && sig != SIGABRT)
94 
95 #endif
96 
97 /* The sighandler_t type is not allowed unless _POSIX_SOURCE is defined. */
98 typedef void _PROTOTYPE( (*__sighandler_t), (int) );
99 
100 /* Macros used as function pointers. */
101 #define SIG_ERR    ((__sighandler_t) -1)	/* error return */
102 #define SIG_DFL	   ((__sighandler_t)  0)	/* default signal handling */
103 #define SIG_IGN	   ((__sighandler_t)  1)	/* ignore signal */
104 #define SIG_HOLD   ((__sighandler_t)  2)	/* block signal */
105 #define SIG_CATCH  ((__sighandler_t)  3)	/* catch signal */
106 
107 #ifdef _POSIX_SOURCE
108 struct sigaction {
109   __sighandler_t sa_handler;	/* SIG_DFL, SIG_IGN, or pointer to function */
110   sigset_t sa_mask;		/* signals to be blocked during handler */
111   int sa_flags;			/* special flags */
112 };
113 
114 /* Fields for sa_flags. */
115 #define SA_ONSTACK   0x0001	/* deliver signal on alternate stack */
116 #define SA_RESETHAND 0x0002	/* reset signal handler when signal caught */
117 #define SA_NODEFER   0x0004	/* don't block signal while catching it */
118 #define SA_RESTART   0x0008	/* automatic system call restart */
119 #define SA_SIGINFO   0x0010	/* extended signal handling */
120 #define SA_NOCLDWAIT 0x0020	/* don't create zombies */
121 #define SA_NOCLDSTOP 0x0040	/* don't receive SIGCHLD when child stops */
122 
123 /* POSIX requires these values for use with sigprocmask(2). */
124 #define SIG_BLOCK          0	/* for blocking signals */
125 #define SIG_UNBLOCK        1	/* for unblocking signals */
126 #define SIG_SETMASK        2	/* for setting the signal mask */
127 #define SIG_INQUIRE        4	/* for internal use only */
128 
129 /* codes for SIGFPE */
130 #define FPE_INTOVF      1      /* integer divide by zero */
131 #define FPE_INTDIV      2      /* integer overflow */
132 #define FPE_FLTDIV      3      /* floating-point divide by zero */
133 #define FPE_FLTOVF      4      /* floating-point overflow */
134 #define FPE_FLTUND      5      /* floating-point underflow */
135 #define FPE_FLTRES      6      /* floating-point inexact result */
136 #define FPE_FLTINV      7      /* floating-point invalid operation */
137 #define FPE_FLTSUB      8      /* subscript out of range */
138 
139 typedef struct sigaltstack {
140   void *ss_sp;
141   int ss_flags;
142   size_t ss_size;
143 } stack_t;
144 
145 #define MINSIGSTKSZ	2048	/* Minimal stack size is 2k */
146 
147 /* Fields for ss_flags */
148 #define SS_ONSTACK      1      /* Process is executing on an alternate stack */
149 #define SS_DISABLE      2      /* Alternate stack is disabled */
150 
151 
152 #endif	/* _POSIX_SOURCE */
153 
154 /* POSIX and ANSI function prototypes. */
155 _PROTOTYPE( int raise, (int _sig)					);
156 _PROTOTYPE( __sighandler_t signal, (int _sig, __sighandler_t _func)	);
157 
158 #ifdef _POSIX_SOURCE
159 _PROTOTYPE( int kill, (pid_t _pid, int _sig)				);
160 _PROTOTYPE( int killpg, (pid_t _pgrp, int _sig)				);
161 _PROTOTYPE( int sigaction,
162     (int _sig, const struct sigaction *_act, struct sigaction *_oact)	);
163 _PROTOTYPE( int sigpending, (sigset_t *_set)				);
164 _PROTOTYPE( int sigprocmask,
165 	    (int _how, const sigset_t *_set, sigset_t *_oset)		);
166 _PROTOTYPE( int sigsuspend, (const sigset_t *_sigmask)			);
167 
168 /* For the sigset functions, only use the library version with error
169  * checking from user programs. System programs need to be able to use
170  * nonstanard signals.
171  */
172 #ifndef _SYSTEM
173 _PROTOTYPE( int sigaddset, (sigset_t *_set, int _sig)			);
174 _PROTOTYPE( int sigdelset, (sigset_t *_set, int _sig)			);
175 _PROTOTYPE( int sigemptyset, (sigset_t *_set)				);
176 _PROTOTYPE( int sigfillset, (sigset_t *_set)				);
177 _PROTOTYPE( int sigismember, (const sigset_t *_set, int _sig)		);
178 #else
179 #define sigaddset(set, sig)	((int) ((*(set) |= (1 << (sig))) && 0))
180 #define sigdelset(set, sig)	((int) ((*(set) &= ~(1 << (sig))) && 0))
181 #define sigemptyset(set)	((int) (*(set) = 0))
182 #define sigfillset(set)		((int) ((*(set) = ~0) && 0))
183 #define sigismember(set, sig)	((*(set) & (1 << (sig))) ? 1 : 0)
184 #endif
185 
186 #endif
187 
188 #endif /* _SIGNAL_H */
189