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. */
38 /* Undefine the macro we used to hide the definition of sys_siglist
39 found in the system header files. */
44 # define NULL (void *) 0
51 # define MAX(a,b) ((a) > (b) ? (a) : (b))
54 static void init_signal_tables
PARAMS ((void));
56 /* Translation table for signal values.
58 Note that this table is generally only accessed when it is used at runtime
59 to initialize signal name and message tables that are indexed by signal
62 Not all of these signals will exist on all systems. This table is the only
63 thing that should have to be updated as new signal numbers are introduced.
64 It's sort of ugly, but at least its portable. */
68 int value
; /* The numeric value from <signal.h> */
69 const char *name
; /* The equivalent symbolic value */
70 #ifndef HAVE_SYS_SIGLIST
71 const char *msg
; /* Short message about this value */
75 #ifndef HAVE_SYS_SIGLIST
76 # define ENTRY(value, name, msg) {value, name, msg}
78 # define ENTRY(value, name, msg) {value, name}
81 static const struct signal_info signal_table
[] =
84 ENTRY(SIGHUP
, "SIGHUP", "Hangup"),
87 ENTRY(SIGINT
, "SIGINT", "Interrupt"),
90 ENTRY(SIGQUIT
, "SIGQUIT", "Quit"),
93 ENTRY(SIGILL
, "SIGILL", "Illegal instruction"),
96 ENTRY(SIGTRAP
, "SIGTRAP", "Trace/breakpoint trap"),
98 /* Put SIGIOT before SIGABRT, so that if SIGIOT==SIGABRT then SIGABRT
99 overrides SIGIOT. SIGABRT is in ANSI and POSIX.1, and SIGIOT isn't. */
101 ENTRY(SIGIOT
, "SIGIOT", "IOT trap"),
103 #if defined (SIGABRT)
104 ENTRY(SIGABRT
, "SIGABRT", "Aborted"),
107 ENTRY(SIGEMT
, "SIGEMT", "Emulation trap"),
110 ENTRY(SIGFPE
, "SIGFPE", "Arithmetic exception"),
112 #if defined (SIGKILL)
113 ENTRY(SIGKILL
, "SIGKILL", "Killed"),
116 ENTRY(SIGBUS
, "SIGBUS", "Bus error"),
118 #if defined (SIGSEGV)
119 ENTRY(SIGSEGV
, "SIGSEGV", "Segmentation fault"),
122 ENTRY(SIGSYS
, "SIGSYS", "Bad system call"),
124 #if defined (SIGPIPE)
125 ENTRY(SIGPIPE
, "SIGPIPE", "Broken pipe"),
127 #if defined (SIGALRM)
128 ENTRY(SIGALRM
, "SIGALRM", "Alarm clock"),
130 #if defined (SIGTERM)
131 ENTRY(SIGTERM
, "SIGTERM", "Terminated"),
133 #if defined (SIGUSR1)
134 ENTRY(SIGUSR1
, "SIGUSR1", "User defined signal 1"),
136 #if defined (SIGUSR2)
137 ENTRY(SIGUSR2
, "SIGUSR2", "User defined signal 2"),
139 /* Put SIGCLD before SIGCHLD, so that if SIGCLD==SIGCHLD then SIGCHLD
140 overrides SIGCLD. SIGCHLD is in POXIX.1 */
142 ENTRY(SIGCLD
, "SIGCLD", "Child status changed"),
144 #if defined (SIGCHLD)
145 ENTRY(SIGCHLD
, "SIGCHLD", "Child status changed"),
148 ENTRY(SIGPWR
, "SIGPWR", "Power fail/restart"),
150 #if defined (SIGWINCH)
151 ENTRY(SIGWINCH
, "SIGWINCH", "Window size changed"),
154 ENTRY(SIGURG
, "SIGURG", "Urgent I/O condition"),
157 /* "I/O pending" has also been suggested, but is misleading since the
158 signal only happens when the process has asked for it, not everytime
160 ENTRY(SIGIO
, "SIGIO", "I/O possible"),
162 #if defined (SIGPOLL)
163 ENTRY(SIGPOLL
, "SIGPOLL", "Pollable event occurred"),
165 #if defined (SIGSTOP)
166 ENTRY(SIGSTOP
, "SIGSTOP", "Stopped (signal)"),
168 #if defined (SIGTSTP)
169 ENTRY(SIGTSTP
, "SIGTSTP", "Stopped (user)"),
171 #if defined (SIGCONT)
172 ENTRY(SIGCONT
, "SIGCONT", "Continued"),
174 #if defined (SIGTTIN)
175 ENTRY(SIGTTIN
, "SIGTTIN", "Stopped (tty input)"),
177 #if defined (SIGTTOU)
178 ENTRY(SIGTTOU
, "SIGTTOU", "Stopped (tty output)"),
180 #if defined (SIGVTALRM)
181 ENTRY(SIGVTALRM
, "SIGVTALRM", "Virtual timer expired"),
183 #if defined (SIGPROF)
184 ENTRY(SIGPROF
, "SIGPROF", "Profiling timer expired"),
186 #if defined (SIGXCPU)
187 ENTRY(SIGXCPU
, "SIGXCPU", "CPU time limit exceeded"),
189 #if defined (SIGXFSZ)
190 ENTRY(SIGXFSZ
, "SIGXFSZ", "File size limit exceeded"),
192 #if defined (SIGWIND)
193 ENTRY(SIGWIND
, "SIGWIND", "SIGWIND"),
195 #if defined (SIGPHONE)
196 ENTRY(SIGPHONE
, "SIGPHONE", "SIGPHONE"),
198 #if defined (SIGLOST)
199 ENTRY(SIGLOST
, "SIGLOST", "Resource lost"),
201 #if defined (SIGWAITING)
202 ENTRY(SIGWAITING
, "SIGWAITING", "Process's LWPs are blocked"),
205 ENTRY(SIGLWP
, "SIGLWP", "Signal LWP"),
207 #if defined (SIGDANGER)
208 ENTRY(SIGDANGER
, "SIGDANGER", "Swap space dangerously low"),
210 #if defined (SIGGRANT)
211 ENTRY(SIGGRANT
, "SIGGRANT", "Monitor mode granted"),
213 #if defined (SIGRETRACT)
214 ENTRY(SIGRETRACT
, "SIGRETRACT", "Need to relinguish monitor mode"),
217 ENTRY(SIGMSG
, "SIGMSG", "Monitor mode data available"),
219 #if defined (SIGSOUND)
220 ENTRY(SIGSOUND
, "SIGSOUND", "Sound completed"),
223 ENTRY(SIGSAK
, "SIGSAK", "Secure attention"),
228 /* Translation table allocated and initialized at runtime. Indexed by the
229 signal value to find the equivalent symbolic value. */
231 static const char **signal_names
;
232 static int num_signal_names
= 0;
234 /* Translation table allocated and initialized at runtime, if it does not
235 already exist in the host environment. Indexed by the signal value to find
236 the descriptive string.
238 We don't export it for use in other modules because even though it has the
239 same name, it differs from other implementations in that it is dynamically
240 initialized rather than statically initialized. */
242 #ifndef HAVE_SYS_SIGLIST
245 static const char **sys_siglist
;
250 static int sys_nsig
= NSIG
;
253 static int sys_nsig
= _NSIG
;
256 extern const char * const sys_siglist
[];
265 init_signal_tables -- initialize the name and message tables
269 static void init_signal_tables ();
273 Using the signal_table, which is initialized at compile time, generate
274 the signal_names and the sys_siglist (if needed) tables, which are
275 indexed at runtime by a specific signal value.
279 The initialization of the tables may fail under low memory conditions,
280 in which case we don't do anything particularly useful, but we don't
281 bomb either. Who knows, it might succeed at a later point if we free
282 some memory in the meantime. In any case, the other routines know
283 how to deal with lack of a table after trying to initialize it. This
284 may or may not be considered to be a bug, that we don't specifically
285 warn about this particular failure mode.
290 init_signal_tables ()
292 const struct signal_info
*eip
;
295 /* If we haven't already scanned the signal_table once to find the maximum
296 signal value, then go find it now. */
298 if (num_signal_names
== 0)
300 for (eip
= signal_table
; eip
-> name
!= NULL
; eip
++)
302 if (eip
-> value
>= num_signal_names
)
304 num_signal_names
= eip
-> value
+ 1;
309 /* Now attempt to allocate the signal_names table, zero it out, and then
310 initialize it from the statically initialized signal_table. */
312 if (signal_names
== NULL
)
314 nbytes
= num_signal_names
* sizeof (char *);
315 if ((signal_names
= (const char **) malloc (nbytes
)) != NULL
)
317 memset (signal_names
, 0, nbytes
);
318 for (eip
= signal_table
; eip
-> name
!= NULL
; eip
++)
320 signal_names
[eip
-> value
] = eip
-> name
;
325 #ifndef HAVE_SYS_SIGLIST
327 /* Now attempt to allocate the sys_siglist table, zero it out, and then
328 initialize it from the statically initialized signal_table. */
330 if (sys_siglist
== NULL
)
332 nbytes
= num_signal_names
* sizeof (char *);
333 if ((sys_siglist
= (const char **) malloc (nbytes
)) != NULL
)
335 memset (sys_siglist
, 0, nbytes
);
336 sys_nsig
= num_signal_names
;
337 for (eip
= signal_table
; eip
-> name
!= NULL
; eip
++)
339 sys_siglist
[eip
-> value
] = eip
-> msg
;
353 signo_max -- return the max signo value
361 Returns the maximum signo value for which a corresponding symbolic
362 name or message is available. Note that in the case where
363 we use the sys_siglist supplied by the system, it is possible for
364 there to be more symbolic names than messages, or vice versa.
365 In fact, the manual page for psignal(3b) explicitly warns that one
366 should check the size of the table (NSIG) before indexing it,
367 since new signal codes may be added to the system before they are
368 added to the table. Thus NSIG might be smaller than value
369 implied by the largest signo value defined in <signal.h>.
371 We return the maximum value that can be used to obtain a meaningful
372 symbolic name or message.
381 if (signal_names
== NULL
)
383 init_signal_tables ();
385 maxsize
= MAX (sys_nsig
, num_signal_names
);
386 return (maxsize
- 1);
394 strsignal -- map a signal number to a signal message string
398 const char *strsignal (int signo)
402 Maps an signal number to an signal message string, the contents of
403 which are implementation defined. On systems which have the external
404 variable sys_siglist, these strings will be the same as the ones used
407 If the supplied signal number is within the valid range of indices
408 for the sys_siglist, but no message is available for the particular
409 signal number, then returns the string "Signal NUM", where NUM is the
412 If the supplied signal number is not a valid index into sys_siglist,
415 The returned string is only guaranteed to be valid only until the
416 next call to strsignal.
420 #ifndef HAVE_STRSIGNAL
429 #ifndef HAVE_SYS_SIGLIST
431 if (signal_names
== NULL
)
433 init_signal_tables ();
438 if ((signo
< 0) || (signo
>= sys_nsig
))
440 /* Out of range, just return NULL */
443 else if ((sys_siglist
== NULL
) || (sys_siglist
[signo
] == NULL
))
445 /* In range, but no sys_siglist or no entry at this index. */
446 sprintf (buf
, "Signal %d", signo
);
447 msg
= (const char *) buf
;
451 /* In range, and a valid message. Just return the message. */
452 msg
= (const char *) sys_siglist
[signo
];
458 #endif /* ! HAVE_STRSIGNAL */
464 strsigno -- map an signal number to a symbolic name string
468 const char *strsigno (int signo)
472 Given an signal number, returns a pointer to a string containing
473 the symbolic name of that signal number, as found in <signal.h>.
475 If the supplied signal number is within the valid range of indices
476 for symbolic names, but no name is available for the particular
477 signal number, then returns the string "Signal NUM", where NUM is
480 If the supplied signal number is not within the range of valid
481 indices, then returns NULL.
485 The contents of the location pointed to are only guaranteed to be
486 valid until the next call to strsigno.
497 if (signal_names
== NULL
)
499 init_signal_tables ();
502 if ((signo
< 0) || (signo
>= num_signal_names
))
504 /* Out of range, just return NULL */
507 else if ((signal_names
== NULL
) || (signal_names
[signo
] == NULL
))
509 /* In range, but no signal_names or no entry at this index. */
510 sprintf (buf
, "Signal %d", signo
);
511 name
= (const char *) buf
;
515 /* In range, and a valid name. Just return the name. */
516 name
= signal_names
[signo
];
527 strtosigno -- map a symbolic signal name to a numeric value
531 int strtosigno (char *name)
535 Given the symbolic name of a signal, map it to a signal number.
536 If no translation is found, returns 0.
548 if (signal_names
== NULL
)
550 init_signal_tables ();
552 for (signo
= 0; signo
< num_signal_names
; signo
++)
554 if ((signal_names
[signo
] != NULL
) &&
555 (strcmp (name
, signal_names
[signo
]) == 0))
560 if (signo
== num_signal_names
)
573 psignal -- print message about signal to stderr
577 void psignal (unsigned signo, char *message);
581 Print to the standard error the message, followed by a colon,
582 followed by the description of the signal specified by signo,
583 followed by a newline.
589 psignal (signo
, message
)
593 if (signal_names
== NULL
)
595 init_signal_tables ();
597 if ((signo
<= 0) || (signo
>= sys_nsig
))
599 fprintf (stderr
, "%s: unknown signal\n", message
);
603 fprintf (stderr
, "%s: %s\n", message
, sys_siglist
[signo
]);
607 #endif /* ! HAVE_PSIGNAL */
610 /* A simple little main that does nothing but print all the signal translations
611 if MAIN is defined and this file is compiled and linked. */
625 maxsigno
= signo_max ();
626 printf ("%d entries in names table.\n", num_signal_names
);
627 printf ("%d entries in messages table.\n", sys_nsig
);
628 printf ("%d is max useful index.\n", maxsigno
);
630 /* Keep printing values until we get to the end of *both* tables, not
631 *either* table. Note that knowing the maximum useful index does *not*
632 relieve us of the responsibility of testing the return pointer for
635 for (signo
= 0; signo
<= maxsigno
; signo
++)
637 name
= strsigno (signo
);
638 name
= (name
== NULL
) ? "<NULL>" : name
;
639 msg
= strsignal (signo
);
640 msg
= (msg
== NULL
) ? "<NULL>" : msg
;
641 printf ("%-4d%-18s%s\n", signo
, name
, msg
);
This page took 0.042766 seconds and 4 git commands to generate.