1 /* Extended support for using signal values.
2 Written by Fred Fish. fnf@cygnus.com
3 This file is in the public domain. */
10 #ifdef LOSING_SYS_SIGLIST
11 #define sys_siglist no_such_symbol
17 /* Routines imported from standard C runtime libraries. */
21 extern void *malloc (size_t size); /* 4.10.3.3 */
22 extern void *memset (void *s, int c, size_t n); /* 4.11.6.1 */
24 extern char *malloc (); /* Standard memory allocater */
25 extern char *memset ();
28 #ifdef LOSING_SYS_SIGLIST
35 # define NULL (void *) 0
42 # define MAX(a,b) ((a) > (b) ? (a) : (b))
45 /* Translation table for signal values.
47 Note that this table is generally only accessed when it is used at runtime
48 to initialize signal name and message tables that are indexed by signal
51 Not all of these signals will exist on all systems. This table is the only
52 thing that should have to be updated as new signal numbers are introduced.
53 It's sort of ugly, but at least its portable. */
57 int value; /* The numeric value from <signal.h> */
58 const char *name; /* The equivalent symbolic value */
59 #ifdef NEED_sys_siglist
60 const char *msg; /* Short message about this value */
64 #ifdef NEED_sys_siglist
65 # define ENTRY(value, name, msg) {value, name, msg}
67 # define ENTRY(value, name, msg) {value, name}
70 static const struct signal_info signal_table[] =
73 ENTRY(SIGHUP, "SIGHUP", "Hangup"),
76 ENTRY(SIGINT, "SIGINT", "Interrupt"),
79 ENTRY(SIGQUIT, "SIGQUIT", "Quit"),
82 ENTRY(SIGILL, "SIGILL", "Illegal instruction"),
85 ENTRY(SIGTRAP, "SIGTRAP", "Trace/breakpoint trap"),
87 /* Put SIGIOT before SIGABRT, so that if SIGIOT==SIGABRT then SIGABRT
88 overrides SIGIOT. SIGABRT is in ANSI and POSIX.1, and SIGIOT isn't. */
90 ENTRY(SIGIOT, "SIGIOT", "IOT trap"),
93 ENTRY(SIGABRT, "SIGABRT", "Aborted"),
96 ENTRY(SIGEMT, "SIGEMT", "Emulation trap"),
99 ENTRY(SIGFPE, "SIGFPE", "Arithmetic exception"),
101 #if defined (SIGKILL)
102 ENTRY(SIGKILL, "SIGKILL", "Killed"),
105 ENTRY(SIGBUS, "SIGBUS", "Bus error"),
107 #if defined (SIGSEGV)
108 ENTRY(SIGSEGV, "SIGSEGV", "Segmentation fault"),
111 ENTRY(SIGSYS, "SIGSYS", "Bad system call"),
113 #if defined (SIGPIPE)
114 ENTRY(SIGPIPE, "SIGPIPE", "Broken pipe"),
116 #if defined (SIGALRM)
117 ENTRY(SIGALRM, "SIGALRM", "Alarm clock"),
119 #if defined (SIGTERM)
120 ENTRY(SIGTERM, "SIGTERM", "Terminated"),
122 #if defined (SIGUSR1)
123 ENTRY(SIGUSR1, "SIGUSR1", "User defined signal 1"),
125 #if defined (SIGUSR2)
126 ENTRY(SIGUSR2, "SIGUSR2", "User defined signal 2"),
128 /* Put SIGCLD before SIGCHLD, so that if SIGCLD==SIGCHLD then SIGCHLD
129 overrides SIGCLD. SIGCHLD is in POXIX.1 */
131 ENTRY(SIGCLD, "SIGCLD", "Child status changed"),
133 #if defined (SIGCHLD)
134 ENTRY(SIGCHLD, "SIGCHLD", "Child status changed"),
137 ENTRY(SIGPWR, "SIGPWR", "Power fail/restart"),
139 #if defined (SIGWINCH)
140 ENTRY(SIGWINCH, "SIGWINCH", "Window size changed"),
143 ENTRY(SIGURG, "SIGURG", "Urgent I/O condition"),
146 /* "I/O pending" has also been suggested, but is misleading since the
147 signal only happens when the process has asked for it, not everytime
149 ENTRY(SIGIO, "SIGIO", "I/O possible"),
151 #if defined (SIGPOLL)
152 ENTRY(SIGPOLL, "SIGPOLL", "Pollable event occurred"),
154 #if defined (SIGSTOP)
155 ENTRY(SIGSTOP, "SIGSTOP", "Stopped (signal)"),
157 #if defined (SIGTSTP)
158 ENTRY(SIGTSTP, "SIGTSTP", "Stopped (user)"),
160 #if defined (SIGCONT)
161 ENTRY(SIGCONT, "SIGCONT", "Continued"),
163 #if defined (SIGTTIN)
164 ENTRY(SIGTTIN, "SIGTTIN", "Stopped (tty input)"),
166 #if defined (SIGTTOU)
167 ENTRY(SIGTTOU, "SIGTTOU", "Stopped (tty output)"),
169 #if defined (SIGVTALRM)
170 ENTRY(SIGVTALRM, "SIGVTALRM", "Virtual timer expired"),
172 #if defined (SIGPROF)
173 ENTRY(SIGPROF, "SIGPROF", "Profiling timer expired"),
175 #if defined (SIGXCPU)
176 ENTRY(SIGXCPU, "SIGXCPU", "CPU time limit exceeded"),
178 #if defined (SIGXFSZ)
179 ENTRY(SIGXFSZ, "SIGXFSZ", "File size limit exceeded"),
181 #if defined (SIGWIND)
182 ENTRY(SIGWIND, "SIGWIND", "SIGWIND"),
184 #if defined (SIGPHONE)
185 ENTRY(SIGPHONE, "SIGPHONE", "SIGPHONE"),
187 #if defined (SIGLOST)
188 ENTRY(SIGLOST, "SIGLOST", "Resource lost"),
190 #if defined (SIGWAITING)
191 ENTRY(SIGWAITING, "SIGWAITING", "Process's LWPs are blocked"),
194 ENTRY(SIGLWP, "SIGLWP", "Signal LWP"),
196 #if defined (SIGDANGER)
197 ENTRY(SIGDANGER, "SIGDANGER", "Swap space dangerously low"),
199 #if defined (SIGGRANT)
200 ENTRY(SIGGRANT, "SIGGRANT", "Monitor mode granted"),
202 #if defined (SIGRETRACT)
203 ENTRY(SIGRETRACT, "SIGRETRACT", "Need to relinguish monitor mode"),
206 ENTRY(SIGMSG, "SIGMSG", "Monitor mode data available"),
208 #if defined (SIGSOUND)
209 ENTRY(SIGSOUND, "SIGSOUND", "Sound completed"),
212 ENTRY(SIGSAK, "SIGSAK", "Secure attention"),
217 /* Translation table allocated and initialized at runtime. Indexed by the
218 signal value to find the equivalent symbolic value. */
220 static const char **signal_names;
221 static int num_signal_names = 0;
223 /* Translation table allocated and initialized at runtime, if it does not
224 already exist in the host environment. Indexed by the signal value to find
225 the descriptive string.
227 We don't export it for use in other modules because even though it has the
228 same name, it differs from other implementations in that it is dynamically
229 initialized rather than statically initialized. */
231 #ifdef NEED_sys_siglist
234 static const char **sys_siglist;
238 static int sys_nsig = NSIG;
239 extern const char * const sys_siglist[];
248 init_signal_tables -- initialize the name and message tables
252 static void init_signal_tables ();
256 Using the signal_table, which is initialized at compile time, generate
257 the signal_names and the sys_siglist (if needed) tables, which are
258 indexed at runtime by a specific signal value.
262 The initialization of the tables may fail under low memory conditions,
263 in which case we don't do anything particularly useful, but we don't
264 bomb either. Who knows, it might succeed at a later point if we free
265 some memory in the meantime. In any case, the other routines know
266 how to deal with lack of a table after trying to initialize it. This
267 may or may not be considered to be a bug, that we don't specifically
268 warn about this particular failure mode.
273 init_signal_tables ()
275 const struct signal_info *eip;
278 /* If we haven't already scanned the signal_table once to find the maximum
279 signal value, then go find it now. */
281 if (num_signal_names == 0)
283 for (eip = signal_table; eip -> name != NULL; eip++)
285 if (eip -> value >= num_signal_names)
287 num_signal_names = eip -> value + 1;
292 /* Now attempt to allocate the signal_names table, zero it out, and then
293 initialize it from the statically initialized signal_table. */
295 if (signal_names == NULL)
297 nbytes = num_signal_names * sizeof (char *);
298 if ((signal_names = (const char **) malloc (nbytes)) != NULL)
300 memset (signal_names, 0, nbytes);
301 for (eip = signal_table; eip -> name != NULL; eip++)
303 signal_names[eip -> value] = eip -> name;
308 #ifdef NEED_sys_siglist
310 /* Now attempt to allocate the sys_siglist table, zero it out, and then
311 initialize it from the statically initialized signal_table. */
313 if (sys_siglist == NULL)
315 nbytes = num_signal_names * sizeof (char *);
316 if ((sys_siglist = (const char **) malloc (nbytes)) != NULL)
318 memset (sys_siglist, 0, nbytes);
319 sys_nsig = num_signal_names;
320 for (eip = signal_table; eip -> name != NULL; eip++)
322 sys_siglist[eip -> value] = eip -> msg;
336 signo_max -- return the max signo value
344 Returns the maximum signo value for which a corresponding symbolic
345 name or message is available. Note that in the case where
346 we use the sys_siglist supplied by the system, it is possible for
347 there to be more symbolic names than messages, or vice versa.
348 In fact, the manual page for psignal(3b) explicitly warns that one
349 should check the size of the table (NSIG) before indexing it,
350 since new signal codes may be added to the system before they are
351 added to the table. Thus NSIG might be smaller than value
352 implied by the largest signo value defined in <signal.h>.
354 We return the maximum value that can be used to obtain a meaningful
355 symbolic name or message.
364 if (signal_names == NULL)
366 init_signal_tables ();
368 maxsize = MAX (sys_nsig, num_signal_names);
369 return (maxsize - 1);
377 strsignal -- map a signal number to a signal message string
381 const char *strsignal (int signo)
385 Maps an signal number to an signal message string, the contents of
386 which are implementation defined. On systems which have the external
387 variable sys_siglist, these strings will be the same as the ones used
390 If the supplied signal number is within the valid range of indices
391 for the sys_siglist, but no message is available for the particular
392 signal number, then returns the string "Signal NUM", where NUM is the
395 If the supplied signal number is not a valid index into sys_siglist,
398 The returned string is only guaranteed to be valid only until the
399 next call to strsignal.
410 #ifdef NEED_sys_siglist
412 if (signal_names == NULL)
414 init_signal_tables ();
419 if ((signo < 0) || (signo >= sys_nsig))
421 /* Out of range, just return NULL */
424 else if ((sys_siglist == NULL) || (sys_siglist[signo] == NULL))
426 /* In range, but no sys_siglist or no entry at this index. */
427 sprintf (buf, "Signal %d", signo);
428 msg = (const char *) buf;
432 /* In range, and a valid message. Just return the message. */
433 msg = (const char *) sys_siglist[signo];
444 strsigno -- map an signal number to a symbolic name string
448 const char *strsigno (int signo)
452 Given an signal number, returns a pointer to a string containing
453 the symbolic name of that signal number, as found in <signal.h>.
455 If the supplied signal number is within the valid range of indices
456 for symbolic names, but no name is available for the particular
457 signal number, then returns the string "Signal NUM", where NUM is
460 If the supplied signal number is not within the range of valid
461 indices, then returns NULL.
465 The contents of the location pointed to are only guaranteed to be
466 valid until the next call to strsigno.
477 if (signal_names == NULL)
479 init_signal_tables ();
482 if ((signo < 0) || (signo >= num_signal_names))
484 /* Out of range, just return NULL */
487 else if ((signal_names == NULL) || (signal_names[signo] == NULL))
489 /* In range, but no signal_names or no entry at this index. */
490 sprintf (buf, "Signal %d", signo);
491 name = (const char *) buf;
495 /* In range, and a valid name. Just return the name. */
496 name = signal_names[signo];
507 strtosigno -- map a symbolic signal name to a numeric value
511 int strtosigno (char *name)
515 Given the symbolic name of a signal, map it to a signal number.
516 If no translation is found, returns 0.
528 if (signal_names == NULL)
530 init_signal_tables ();
532 for (signo = 0; signo < num_signal_names; signo++)
534 if ((signal_names[signo] != NULL) &&
535 (strcmp (name, signal_names[signo]) == 0))
540 if (signo == num_signal_names)
553 psignal -- print message about signal to stderr
557 void psignal (unsigned signo, char *message);
561 Print to the standard error the message, followed by a colon,
562 followed by the description of the signal specified by signo,
563 followed by a newline.
569 psignal (signo, message)
573 if (signal_names == NULL)
575 init_signal_tables ();
577 if ((signo <= 0) || (signo >= sys_nsig))
579 fprintf (stderr, "%s: unknown signal\n", message);
583 fprintf (stderr, "%s: %s\n", message, sys_siglist[signo]);
587 #endif /* NEED_psignal */
590 /* A simple little main that does nothing but print all the signal translations
591 if MAIN is defined and this file is compiled and linked. */
605 maxsigno = signo_max ();
606 printf ("%d entries in names table.\n", num_signal_names);
607 printf ("%d entries in messages table.\n", sys_nsig);
608 printf ("%d is max useful index.\n", maxsigno);
610 /* Keep printing values until we get to the end of *both* tables, not
611 *either* table. Note that knowing the maximum useful index does *not*
612 relieve us of the responsibility of testing the return pointer for
615 for (signo = 0; signo <= maxsigno; signo++)
617 name = strsigno (signo);
618 name = (name == NULL) ? "<NULL>" : name;
619 msg = strsignal (signo);
620 msg = (msg == NULL) ? "<NULL>" : msg;
621 printf ("%-4d%-18s%s\n", signo, name, msg);