1 /* Extended support for using signal values.
2 Written by Fred Fish. fnf@cygnus.com
3 This file is in the public domain. */
10 /* We need to declare sys_siglist, because even if the system provides
11 it we can't assume that it is declared in <signal.h> (for example,
12 SunOS provides sys_siglist, but it does not declare it in any
13 header file). fHowever, we can't declare sys_siglist portably,
14 because on some systems it is declared with const and on some
15 systems it is declared without const. If we were using autoconf,
16 we could work out the right declaration. Until, then we just
17 ignore any declaration in the system header files, and always
18 declare it ourselves. With luck, this will always work. */
19 #define sys_siglist no_such_symbol
24 /* Routines imported from standard C runtime libraries. */
28 extern void *malloc (size_t size
); /* 4.10.3.3 */
29 extern void *memset (void *s
, int c
, size_t n
); /* 4.11.6.1 */
31 extern char *malloc (); /* Standard memory allocater */
32 extern char *memset ();
35 /* Undefine the macro we used to hide the definition of sys_siglist
36 found in the system header files. */
41 # define NULL (void *) 0
48 # define MAX(a,b) ((a) > (b) ? (a) : (b))
51 static void init_signal_tables
PARAMS ((void));
53 /* Translation table for signal values.
55 Note that this table is generally only accessed when it is used at runtime
56 to initialize signal name and message tables that are indexed by signal
59 Not all of these signals will exist on all systems. This table is the only
60 thing that should have to be updated as new signal numbers are introduced.
61 It's sort of ugly, but at least its portable. */
65 int value
; /* The numeric value from <signal.h> */
66 const char *name
; /* The equivalent symbolic value */
67 #ifndef HAVE_SYS_SIGLIST
68 const char *msg
; /* Short message about this value */
72 #ifndef HAVE_SYS_SIGLIST
73 # define ENTRY(value, name, msg) {value, name, msg}
75 # define ENTRY(value, name, msg) {value, name}
78 static const struct signal_info signal_table
[] =
81 ENTRY(SIGHUP
, "SIGHUP", "Hangup"),
84 ENTRY(SIGINT
, "SIGINT", "Interrupt"),
87 ENTRY(SIGQUIT
, "SIGQUIT", "Quit"),
90 ENTRY(SIGILL
, "SIGILL", "Illegal instruction"),
93 ENTRY(SIGTRAP
, "SIGTRAP", "Trace/breakpoint trap"),
95 /* Put SIGIOT before SIGABRT, so that if SIGIOT==SIGABRT then SIGABRT
96 overrides SIGIOT. SIGABRT is in ANSI and POSIX.1, and SIGIOT isn't. */
98 ENTRY(SIGIOT
, "SIGIOT", "IOT trap"),
100 #if defined (SIGABRT)
101 ENTRY(SIGABRT
, "SIGABRT", "Aborted"),
104 ENTRY(SIGEMT
, "SIGEMT", "Emulation trap"),
107 ENTRY(SIGFPE
, "SIGFPE", "Arithmetic exception"),
109 #if defined (SIGKILL)
110 ENTRY(SIGKILL
, "SIGKILL", "Killed"),
113 ENTRY(SIGBUS
, "SIGBUS", "Bus error"),
115 #if defined (SIGSEGV)
116 ENTRY(SIGSEGV
, "SIGSEGV", "Segmentation fault"),
119 ENTRY(SIGSYS
, "SIGSYS", "Bad system call"),
121 #if defined (SIGPIPE)
122 ENTRY(SIGPIPE
, "SIGPIPE", "Broken pipe"),
124 #if defined (SIGALRM)
125 ENTRY(SIGALRM
, "SIGALRM", "Alarm clock"),
127 #if defined (SIGTERM)
128 ENTRY(SIGTERM
, "SIGTERM", "Terminated"),
130 #if defined (SIGUSR1)
131 ENTRY(SIGUSR1
, "SIGUSR1", "User defined signal 1"),
133 #if defined (SIGUSR2)
134 ENTRY(SIGUSR2
, "SIGUSR2", "User defined signal 2"),
136 /* Put SIGCLD before SIGCHLD, so that if SIGCLD==SIGCHLD then SIGCHLD
137 overrides SIGCLD. SIGCHLD is in POXIX.1 */
139 ENTRY(SIGCLD
, "SIGCLD", "Child status changed"),
141 #if defined (SIGCHLD)
142 ENTRY(SIGCHLD
, "SIGCHLD", "Child status changed"),
145 ENTRY(SIGPWR
, "SIGPWR", "Power fail/restart"),
147 #if defined (SIGWINCH)
148 ENTRY(SIGWINCH
, "SIGWINCH", "Window size changed"),
151 ENTRY(SIGURG
, "SIGURG", "Urgent I/O condition"),
154 /* "I/O pending" has also been suggested, but is misleading since the
155 signal only happens when the process has asked for it, not everytime
157 ENTRY(SIGIO
, "SIGIO", "I/O possible"),
159 #if defined (SIGPOLL)
160 ENTRY(SIGPOLL
, "SIGPOLL", "Pollable event occurred"),
162 #if defined (SIGSTOP)
163 ENTRY(SIGSTOP
, "SIGSTOP", "Stopped (signal)"),
165 #if defined (SIGTSTP)
166 ENTRY(SIGTSTP
, "SIGTSTP", "Stopped (user)"),
168 #if defined (SIGCONT)
169 ENTRY(SIGCONT
, "SIGCONT", "Continued"),
171 #if defined (SIGTTIN)
172 ENTRY(SIGTTIN
, "SIGTTIN", "Stopped (tty input)"),
174 #if defined (SIGTTOU)
175 ENTRY(SIGTTOU
, "SIGTTOU", "Stopped (tty output)"),
177 #if defined (SIGVTALRM)
178 ENTRY(SIGVTALRM
, "SIGVTALRM", "Virtual timer expired"),
180 #if defined (SIGPROF)
181 ENTRY(SIGPROF
, "SIGPROF", "Profiling timer expired"),
183 #if defined (SIGXCPU)
184 ENTRY(SIGXCPU
, "SIGXCPU", "CPU time limit exceeded"),
186 #if defined (SIGXFSZ)
187 ENTRY(SIGXFSZ
, "SIGXFSZ", "File size limit exceeded"),
189 #if defined (SIGWIND)
190 ENTRY(SIGWIND
, "SIGWIND", "SIGWIND"),
192 #if defined (SIGPHONE)
193 ENTRY(SIGPHONE
, "SIGPHONE", "SIGPHONE"),
195 #if defined (SIGLOST)
196 ENTRY(SIGLOST
, "SIGLOST", "Resource lost"),
198 #if defined (SIGWAITING)
199 ENTRY(SIGWAITING
, "SIGWAITING", "Process's LWPs are blocked"),
202 ENTRY(SIGLWP
, "SIGLWP", "Signal LWP"),
204 #if defined (SIGDANGER)
205 ENTRY(SIGDANGER
, "SIGDANGER", "Swap space dangerously low"),
207 #if defined (SIGGRANT)
208 ENTRY(SIGGRANT
, "SIGGRANT", "Monitor mode granted"),
210 #if defined (SIGRETRACT)
211 ENTRY(SIGRETRACT
, "SIGRETRACT", "Need to relinguish monitor mode"),
214 ENTRY(SIGMSG
, "SIGMSG", "Monitor mode data available"),
216 #if defined (SIGSOUND)
217 ENTRY(SIGSOUND
, "SIGSOUND", "Sound completed"),
220 ENTRY(SIGSAK
, "SIGSAK", "Secure attention"),
225 /* Translation table allocated and initialized at runtime. Indexed by the
226 signal value to find the equivalent symbolic value. */
228 static const char **signal_names
;
229 static int num_signal_names
= 0;
231 /* Translation table allocated and initialized at runtime, if it does not
232 already exist in the host environment. Indexed by the signal value to find
233 the descriptive string.
235 We don't export it for use in other modules because even though it has the
236 same name, it differs from other implementations in that it is dynamically
237 initialized rather than statically initialized. */
239 #ifndef HAVE_SYS_SIGLIST
242 static const char **sys_siglist
;
247 static int sys_nsig
= NSIG
;
250 static int sys_nsig
= _NSIG
;
253 extern const char * const sys_siglist
[];
262 init_signal_tables -- initialize the name and message tables
266 static void init_signal_tables ();
270 Using the signal_table, which is initialized at compile time, generate
271 the signal_names and the sys_siglist (if needed) tables, which are
272 indexed at runtime by a specific signal value.
276 The initialization of the tables may fail under low memory conditions,
277 in which case we don't do anything particularly useful, but we don't
278 bomb either. Who knows, it might succeed at a later point if we free
279 some memory in the meantime. In any case, the other routines know
280 how to deal with lack of a table after trying to initialize it. This
281 may or may not be considered to be a bug, that we don't specifically
282 warn about this particular failure mode.
287 init_signal_tables ()
289 const struct signal_info
*eip
;
292 /* If we haven't already scanned the signal_table once to find the maximum
293 signal value, then go find it now. */
295 if (num_signal_names
== 0)
297 for (eip
= signal_table
; eip
-> name
!= NULL
; eip
++)
299 if (eip
-> value
>= num_signal_names
)
301 num_signal_names
= eip
-> value
+ 1;
306 /* Now attempt to allocate the signal_names table, zero it out, and then
307 initialize it from the statically initialized signal_table. */
309 if (signal_names
== NULL
)
311 nbytes
= num_signal_names
* sizeof (char *);
312 if ((signal_names
= (const char **) malloc (nbytes
)) != NULL
)
314 memset (signal_names
, 0, nbytes
);
315 for (eip
= signal_table
; eip
-> name
!= NULL
; eip
++)
317 signal_names
[eip
-> value
] = eip
-> name
;
322 #ifndef HAVE_SYS_SIGLIST
324 /* Now attempt to allocate the sys_siglist table, zero it out, and then
325 initialize it from the statically initialized signal_table. */
327 if (sys_siglist
== NULL
)
329 nbytes
= num_signal_names
* sizeof (char *);
330 if ((sys_siglist
= (const char **) malloc (nbytes
)) != NULL
)
332 memset (sys_siglist
, 0, nbytes
);
333 sys_nsig
= num_signal_names
;
334 for (eip
= signal_table
; eip
-> name
!= NULL
; eip
++)
336 sys_siglist
[eip
-> value
] = eip
-> msg
;
350 signo_max -- return the max signo value
358 Returns the maximum signo value for which a corresponding symbolic
359 name or message is available. Note that in the case where
360 we use the sys_siglist supplied by the system, it is possible for
361 there to be more symbolic names than messages, or vice versa.
362 In fact, the manual page for psignal(3b) explicitly warns that one
363 should check the size of the table (NSIG) before indexing it,
364 since new signal codes may be added to the system before they are
365 added to the table. Thus NSIG might be smaller than value
366 implied by the largest signo value defined in <signal.h>.
368 We return the maximum value that can be used to obtain a meaningful
369 symbolic name or message.
378 if (signal_names
== NULL
)
380 init_signal_tables ();
382 maxsize
= MAX (sys_nsig
, num_signal_names
);
383 return (maxsize
- 1);
391 strsignal -- map a signal number to a signal message string
395 const char *strsignal (int signo)
399 Maps an signal number to an signal message string, the contents of
400 which are implementation defined. On systems which have the external
401 variable sys_siglist, these strings will be the same as the ones used
404 If the supplied signal number is within the valid range of indices
405 for the sys_siglist, but no message is available for the particular
406 signal number, then returns the string "Signal NUM", where NUM is the
409 If the supplied signal number is not a valid index into sys_siglist,
412 The returned string is only guaranteed to be valid only until the
413 next call to strsignal.
417 #ifndef HAVE_STRSIGNAL
426 #ifndef HAVE_SYS_SIGLIST
428 if (signal_names
== NULL
)
430 init_signal_tables ();
435 if ((signo
< 0) || (signo
>= sys_nsig
))
437 /* Out of range, just return NULL */
440 else if ((sys_siglist
== NULL
) || (sys_siglist
[signo
] == NULL
))
442 /* In range, but no sys_siglist or no entry at this index. */
443 sprintf (buf
, "Signal %d", signo
);
444 msg
= (const char *) buf
;
448 /* In range, and a valid message. Just return the message. */
449 msg
= (const char *) sys_siglist
[signo
];
455 #endif /* ! HAVE_STRSIGNAL */
461 strsigno -- map an signal number to a symbolic name string
465 const char *strsigno (int signo)
469 Given an signal number, returns a pointer to a string containing
470 the symbolic name of that signal number, as found in <signal.h>.
472 If the supplied signal number is within the valid range of indices
473 for symbolic names, but no name is available for the particular
474 signal number, then returns the string "Signal NUM", where NUM is
477 If the supplied signal number is not within the range of valid
478 indices, then returns NULL.
482 The contents of the location pointed to are only guaranteed to be
483 valid until the next call to strsigno.
494 if (signal_names
== NULL
)
496 init_signal_tables ();
499 if ((signo
< 0) || (signo
>= num_signal_names
))
501 /* Out of range, just return NULL */
504 else if ((signal_names
== NULL
) || (signal_names
[signo
] == NULL
))
506 /* In range, but no signal_names or no entry at this index. */
507 sprintf (buf
, "Signal %d", signo
);
508 name
= (const char *) buf
;
512 /* In range, and a valid name. Just return the name. */
513 name
= signal_names
[signo
];
524 strtosigno -- map a symbolic signal name to a numeric value
528 int strtosigno (char *name)
532 Given the symbolic name of a signal, map it to a signal number.
533 If no translation is found, returns 0.
545 if (signal_names
== NULL
)
547 init_signal_tables ();
549 for (signo
= 0; signo
< num_signal_names
; signo
++)
551 if ((signal_names
[signo
] != NULL
) &&
552 (strcmp (name
, signal_names
[signo
]) == 0))
557 if (signo
== num_signal_names
)
570 psignal -- print message about signal to stderr
574 void psignal (unsigned signo, char *message);
578 Print to the standard error the message, followed by a colon,
579 followed by the description of the signal specified by signo,
580 followed by a newline.
586 psignal (signo
, message
)
590 if (signal_names
== NULL
)
592 init_signal_tables ();
594 if ((signo
<= 0) || (signo
>= sys_nsig
))
596 fprintf (stderr
, "%s: unknown signal\n", message
);
600 fprintf (stderr
, "%s: %s\n", message
, sys_siglist
[signo
]);
604 #endif /* ! HAVE_PSIGNAL */
607 /* A simple little main that does nothing but print all the signal translations
608 if MAIN is defined and this file is compiled and linked. */
622 maxsigno
= signo_max ();
623 printf ("%d entries in names table.\n", num_signal_names
);
624 printf ("%d entries in messages table.\n", sys_nsig
);
625 printf ("%d is max useful index.\n", maxsigno
);
627 /* Keep printing values until we get to the end of *both* tables, not
628 *either* table. Note that knowing the maximum useful index does *not*
629 relieve us of the responsibility of testing the return pointer for
632 for (signo
= 0; signo
<= maxsigno
; signo
++)
634 name
= strsigno (signo
);
635 name
= (name
== NULL
) ? "<NULL>" : name
;
636 msg
= strsignal (signo
);
637 msg
= (msg
== NULL
) ? "<NULL>" : msg
;
638 printf ("%-4d%-18s%s\n", signo
, name
, msg
);
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