608 lines
15 KiB
C
608 lines
15 KiB
C
/* Extended support for using signal values.
|
|
Written by Fred Fish. fnf@cygnus.com
|
|
This file is in the public domain. */
|
|
|
|
#include "config.h"
|
|
#include "ansidecl.h"
|
|
#include "libiberty.h"
|
|
|
|
/* We need to declare sys_siglist, because even if the system provides
|
|
it we can't assume that it is declared in <signal.h> (for example,
|
|
SunOS provides sys_siglist, but it does not declare it in any
|
|
header file). However, we can't declare sys_siglist portably,
|
|
because on some systems it is declared with const and on some
|
|
systems it is declared without const. If we were using autoconf,
|
|
we could work out the right declaration. Until, then we just
|
|
ignore any declaration in the system header files, and always
|
|
declare it ourselves. With luck, this will always work. */
|
|
#define sys_siglist no_such_symbol
|
|
#define sys_nsig sys_nsig__no_such_symbol
|
|
|
|
#include <stdio.h>
|
|
#include <signal.h>
|
|
|
|
/* Routines imported from standard C runtime libraries. */
|
|
|
|
#ifdef HAVE_STDLIB_H
|
|
#include <stdlib.h>
|
|
#else
|
|
extern PTR malloc ();
|
|
#endif
|
|
|
|
#ifdef HAVE_STRING_H
|
|
#include <string.h>
|
|
#else
|
|
extern PTR memset ();
|
|
#endif
|
|
|
|
/* Undefine the macro we used to hide the definition of sys_siglist
|
|
found in the system header files. */
|
|
#undef sys_siglist
|
|
#undef sys_nsig
|
|
|
|
#ifndef NULL
|
|
# define NULL (void *) 0
|
|
#endif
|
|
|
|
#ifndef MAX
|
|
# define MAX(a,b) ((a) > (b) ? (a) : (b))
|
|
#endif
|
|
|
|
static void init_signal_tables (void);
|
|
|
|
/* Translation table for signal values.
|
|
|
|
Note that this table is generally only accessed when it is used at runtime
|
|
to initialize signal name and message tables that are indexed by signal
|
|
value.
|
|
|
|
Not all of these signals will exist on all systems. This table is the only
|
|
thing that should have to be updated as new signal numbers are introduced.
|
|
It's sort of ugly, but at least its portable. */
|
|
|
|
struct signal_info
|
|
{
|
|
const int value; /* The numeric value from <signal.h> */
|
|
const char *const name; /* The equivalent symbolic value */
|
|
#ifndef HAVE_SYS_SIGLIST
|
|
const char *const msg; /* Short message about this value */
|
|
#endif
|
|
};
|
|
|
|
#ifndef HAVE_SYS_SIGLIST
|
|
# define ENTRY(value, name, msg) {value, name, msg}
|
|
#else
|
|
# define ENTRY(value, name, msg) {value, name}
|
|
#endif
|
|
|
|
static const struct signal_info signal_table[] =
|
|
{
|
|
#if defined (SIGHUP)
|
|
ENTRY(SIGHUP, "SIGHUP", "Hangup"),
|
|
#endif
|
|
#if defined (SIGINT)
|
|
ENTRY(SIGINT, "SIGINT", "Interrupt"),
|
|
#endif
|
|
#if defined (SIGQUIT)
|
|
ENTRY(SIGQUIT, "SIGQUIT", "Quit"),
|
|
#endif
|
|
#if defined (SIGILL)
|
|
ENTRY(SIGILL, "SIGILL", "Illegal instruction"),
|
|
#endif
|
|
#if defined (SIGTRAP)
|
|
ENTRY(SIGTRAP, "SIGTRAP", "Trace/breakpoint trap"),
|
|
#endif
|
|
/* Put SIGIOT before SIGABRT, so that if SIGIOT==SIGABRT then SIGABRT
|
|
overrides SIGIOT. SIGABRT is in ANSI and POSIX.1, and SIGIOT isn't. */
|
|
#if defined (SIGIOT)
|
|
ENTRY(SIGIOT, "SIGIOT", "IOT trap"),
|
|
#endif
|
|
#if defined (SIGABRT)
|
|
ENTRY(SIGABRT, "SIGABRT", "Aborted"),
|
|
#endif
|
|
#if defined (SIGEMT)
|
|
ENTRY(SIGEMT, "SIGEMT", "Emulation trap"),
|
|
#endif
|
|
#if defined (SIGFPE)
|
|
ENTRY(SIGFPE, "SIGFPE", "Arithmetic exception"),
|
|
#endif
|
|
#if defined (SIGKILL)
|
|
ENTRY(SIGKILL, "SIGKILL", "Killed"),
|
|
#endif
|
|
#if defined (SIGBUS)
|
|
ENTRY(SIGBUS, "SIGBUS", "Bus error"),
|
|
#endif
|
|
#if defined (SIGSEGV)
|
|
ENTRY(SIGSEGV, "SIGSEGV", "Segmentation fault"),
|
|
#endif
|
|
#if defined (SIGSYS)
|
|
ENTRY(SIGSYS, "SIGSYS", "Bad system call"),
|
|
#endif
|
|
#if defined (SIGPIPE)
|
|
ENTRY(SIGPIPE, "SIGPIPE", "Broken pipe"),
|
|
#endif
|
|
#if defined (SIGALRM)
|
|
ENTRY(SIGALRM, "SIGALRM", "Alarm clock"),
|
|
#endif
|
|
#if defined (SIGTERM)
|
|
ENTRY(SIGTERM, "SIGTERM", "Terminated"),
|
|
#endif
|
|
#if defined (SIGUSR1)
|
|
ENTRY(SIGUSR1, "SIGUSR1", "User defined signal 1"),
|
|
#endif
|
|
#if defined (SIGUSR2)
|
|
ENTRY(SIGUSR2, "SIGUSR2", "User defined signal 2"),
|
|
#endif
|
|
/* Put SIGCLD before SIGCHLD, so that if SIGCLD==SIGCHLD then SIGCHLD
|
|
overrides SIGCLD. SIGCHLD is in POXIX.1 */
|
|
#if defined (SIGCLD)
|
|
ENTRY(SIGCLD, "SIGCLD", "Child status changed"),
|
|
#endif
|
|
#if defined (SIGCHLD)
|
|
ENTRY(SIGCHLD, "SIGCHLD", "Child status changed"),
|
|
#endif
|
|
#if defined (SIGPWR)
|
|
ENTRY(SIGPWR, "SIGPWR", "Power fail/restart"),
|
|
#endif
|
|
#if defined (SIGWINCH)
|
|
ENTRY(SIGWINCH, "SIGWINCH", "Window size changed"),
|
|
#endif
|
|
#if defined (SIGURG)
|
|
ENTRY(SIGURG, "SIGURG", "Urgent I/O condition"),
|
|
#endif
|
|
#if defined (SIGIO)
|
|
/* "I/O pending" has also been suggested, but is misleading since the
|
|
signal only happens when the process has asked for it, not everytime
|
|
I/O is pending. */
|
|
ENTRY(SIGIO, "SIGIO", "I/O possible"),
|
|
#endif
|
|
#if defined (SIGPOLL)
|
|
ENTRY(SIGPOLL, "SIGPOLL", "Pollable event occurred"),
|
|
#endif
|
|
#if defined (SIGSTOP)
|
|
ENTRY(SIGSTOP, "SIGSTOP", "Stopped (signal)"),
|
|
#endif
|
|
#if defined (SIGTSTP)
|
|
ENTRY(SIGTSTP, "SIGTSTP", "Stopped (user)"),
|
|
#endif
|
|
#if defined (SIGCONT)
|
|
ENTRY(SIGCONT, "SIGCONT", "Continued"),
|
|
#endif
|
|
#if defined (SIGTTIN)
|
|
ENTRY(SIGTTIN, "SIGTTIN", "Stopped (tty input)"),
|
|
#endif
|
|
#if defined (SIGTTOU)
|
|
ENTRY(SIGTTOU, "SIGTTOU", "Stopped (tty output)"),
|
|
#endif
|
|
#if defined (SIGVTALRM)
|
|
ENTRY(SIGVTALRM, "SIGVTALRM", "Virtual timer expired"),
|
|
#endif
|
|
#if defined (SIGPROF)
|
|
ENTRY(SIGPROF, "SIGPROF", "Profiling timer expired"),
|
|
#endif
|
|
#if defined (SIGXCPU)
|
|
ENTRY(SIGXCPU, "SIGXCPU", "CPU time limit exceeded"),
|
|
#endif
|
|
#if defined (SIGXFSZ)
|
|
ENTRY(SIGXFSZ, "SIGXFSZ", "File size limit exceeded"),
|
|
#endif
|
|
#if defined (SIGWIND)
|
|
ENTRY(SIGWIND, "SIGWIND", "SIGWIND"),
|
|
#endif
|
|
#if defined (SIGPHONE)
|
|
ENTRY(SIGPHONE, "SIGPHONE", "SIGPHONE"),
|
|
#endif
|
|
#if defined (SIGLOST)
|
|
ENTRY(SIGLOST, "SIGLOST", "Resource lost"),
|
|
#endif
|
|
#if defined (SIGWAITING)
|
|
ENTRY(SIGWAITING, "SIGWAITING", "Process's LWPs are blocked"),
|
|
#endif
|
|
#if defined (SIGLWP)
|
|
ENTRY(SIGLWP, "SIGLWP", "Signal LWP"),
|
|
#endif
|
|
#if defined (SIGDANGER)
|
|
ENTRY(SIGDANGER, "SIGDANGER", "Swap space dangerously low"),
|
|
#endif
|
|
#if defined (SIGGRANT)
|
|
ENTRY(SIGGRANT, "SIGGRANT", "Monitor mode granted"),
|
|
#endif
|
|
#if defined (SIGRETRACT)
|
|
ENTRY(SIGRETRACT, "SIGRETRACT", "Need to relinguish monitor mode"),
|
|
#endif
|
|
#if defined (SIGMSG)
|
|
ENTRY(SIGMSG, "SIGMSG", "Monitor mode data available"),
|
|
#endif
|
|
#if defined (SIGSOUND)
|
|
ENTRY(SIGSOUND, "SIGSOUND", "Sound completed"),
|
|
#endif
|
|
#if defined (SIGSAK)
|
|
ENTRY(SIGSAK, "SIGSAK", "Secure attention"),
|
|
#endif
|
|
ENTRY(0, NULL, NULL)
|
|
};
|
|
|
|
/* Translation table allocated and initialized at runtime. Indexed by the
|
|
signal value to find the equivalent symbolic value. */
|
|
|
|
static const char **signal_names;
|
|
static int num_signal_names = 0;
|
|
|
|
/* Translation table allocated and initialized at runtime, if it does not
|
|
already exist in the host environment. Indexed by the signal value to find
|
|
the descriptive string.
|
|
|
|
We don't export it for use in other modules because even though it has the
|
|
same name, it differs from other implementations in that it is dynamically
|
|
initialized rather than statically initialized. */
|
|
|
|
#ifndef HAVE_SYS_SIGLIST
|
|
|
|
static int sys_nsig;
|
|
static const char **sys_siglist;
|
|
|
|
#else
|
|
|
|
#ifdef NSIG
|
|
static int sys_nsig = NSIG;
|
|
#else
|
|
#ifdef _NSIG
|
|
static int sys_nsig = _NSIG;
|
|
#endif
|
|
#endif
|
|
extern const char * const sys_siglist[];
|
|
|
|
#endif
|
|
|
|
|
|
/*
|
|
|
|
NAME
|
|
|
|
init_signal_tables -- initialize the name and message tables
|
|
|
|
SYNOPSIS
|
|
|
|
static void init_signal_tables ();
|
|
|
|
DESCRIPTION
|
|
|
|
Using the signal_table, which is initialized at compile time, generate
|
|
the signal_names and the sys_siglist (if needed) tables, which are
|
|
indexed at runtime by a specific signal value.
|
|
|
|
BUGS
|
|
|
|
The initialization of the tables may fail under low memory conditions,
|
|
in which case we don't do anything particularly useful, but we don't
|
|
bomb either. Who knows, it might succeed at a later point if we free
|
|
some memory in the meantime. In any case, the other routines know
|
|
how to deal with lack of a table after trying to initialize it. This
|
|
may or may not be considered to be a bug, that we don't specifically
|
|
warn about this particular failure mode.
|
|
|
|
*/
|
|
|
|
static void
|
|
init_signal_tables (void)
|
|
{
|
|
const struct signal_info *eip;
|
|
int nbytes;
|
|
|
|
/* If we haven't already scanned the signal_table once to find the maximum
|
|
signal value, then go find it now. */
|
|
|
|
if (num_signal_names == 0)
|
|
{
|
|
for (eip = signal_table; eip -> name != NULL; eip++)
|
|
{
|
|
if (eip -> value >= num_signal_names)
|
|
{
|
|
num_signal_names = eip -> value + 1;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Now attempt to allocate the signal_names table, zero it out, and then
|
|
initialize it from the statically initialized signal_table. */
|
|
|
|
if (signal_names == NULL)
|
|
{
|
|
nbytes = num_signal_names * sizeof (char *);
|
|
if ((signal_names = (const char **) malloc (nbytes)) != NULL)
|
|
{
|
|
memset (signal_names, 0, nbytes);
|
|
for (eip = signal_table; eip -> name != NULL; eip++)
|
|
{
|
|
signal_names[eip -> value] = eip -> name;
|
|
}
|
|
}
|
|
}
|
|
|
|
#ifndef HAVE_SYS_SIGLIST
|
|
|
|
/* Now attempt to allocate the sys_siglist table, zero it out, and then
|
|
initialize it from the statically initialized signal_table. */
|
|
|
|
if (sys_siglist == NULL)
|
|
{
|
|
nbytes = num_signal_names * sizeof (char *);
|
|
if ((sys_siglist = (const char **) malloc (nbytes)) != NULL)
|
|
{
|
|
memset (sys_siglist, 0, nbytes);
|
|
sys_nsig = num_signal_names;
|
|
for (eip = signal_table; eip -> name != NULL; eip++)
|
|
{
|
|
sys_siglist[eip -> value] = eip -> msg;
|
|
}
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
/*
|
|
|
|
@deftypefn Extension int signo_max (void)
|
|
|
|
Returns the maximum signal value for which a corresponding symbolic
|
|
name or message is available. Note that in the case where we use the
|
|
@code{sys_siglist} supplied by the system, it is possible for there to
|
|
be more symbolic names than messages, or vice versa. In fact, the
|
|
manual page for @code{psignal(3b)} explicitly warns that one should
|
|
check the size of the table (@code{NSIG}) before indexing it, since
|
|
new signal codes may be added to the system before they are added to
|
|
the table. Thus @code{NSIG} might be smaller than value implied by
|
|
the largest signo value defined in @code{<signal.h>}.
|
|
|
|
We return the maximum value that can be used to obtain a meaningful
|
|
symbolic name or message.
|
|
|
|
@end deftypefn
|
|
|
|
*/
|
|
|
|
int
|
|
signo_max (void)
|
|
{
|
|
int maxsize;
|
|
|
|
if (signal_names == NULL)
|
|
{
|
|
init_signal_tables ();
|
|
}
|
|
maxsize = MAX (sys_nsig, num_signal_names);
|
|
return (maxsize - 1);
|
|
}
|
|
|
|
|
|
/*
|
|
|
|
@deftypefn Supplemental {const char *} strsignal (int @var{signo})
|
|
|
|
Maps an signal number to an signal message string, the contents of
|
|
which are implementation defined. On systems which have the external
|
|
variable @code{sys_siglist}, these strings will be the same as the
|
|
ones used by @code{psignal()}.
|
|
|
|
If the supplied signal number is within the valid range of indices for
|
|
the @code{sys_siglist}, but no message is available for the particular
|
|
signal number, then returns the string @samp{Signal @var{num}}, where
|
|
@var{num} is the signal number.
|
|
|
|
If the supplied signal number is not a valid index into
|
|
@code{sys_siglist}, returns @code{NULL}.
|
|
|
|
The returned string is only guaranteed to be valid only until the next
|
|
call to @code{strsignal}.
|
|
|
|
@end deftypefn
|
|
|
|
*/
|
|
|
|
#ifndef HAVE_STRSIGNAL
|
|
|
|
const char *
|
|
strsignal (int signo)
|
|
{
|
|
const char *msg;
|
|
static char buf[32];
|
|
|
|
#ifndef HAVE_SYS_SIGLIST
|
|
|
|
if (signal_names == NULL)
|
|
{
|
|
init_signal_tables ();
|
|
}
|
|
|
|
#endif
|
|
|
|
if ((signo < 0) || (signo >= sys_nsig))
|
|
{
|
|
/* Out of range, just return NULL */
|
|
msg = NULL;
|
|
}
|
|
else if ((sys_siglist == NULL) || (sys_siglist[signo] == NULL))
|
|
{
|
|
/* In range, but no sys_siglist or no entry at this index. */
|
|
sprintf (buf, "Signal %d", signo);
|
|
msg = (const char *) buf;
|
|
}
|
|
else
|
|
{
|
|
/* In range, and a valid message. Just return the message. */
|
|
msg = (const char *) sys_siglist[signo];
|
|
}
|
|
|
|
return (msg);
|
|
}
|
|
|
|
#endif /* ! HAVE_STRSIGNAL */
|
|
|
|
/*
|
|
|
|
@deftypefn Extension {const char*} strsigno (int @var{signo})
|
|
|
|
Given an signal number, returns a pointer to a string containing the
|
|
symbolic name of that signal number, as found in @code{<signal.h>}.
|
|
|
|
If the supplied signal number is within the valid range of indices for
|
|
symbolic names, but no name is available for the particular signal
|
|
number, then returns the string @samp{Signal @var{num}}, where
|
|
@var{num} is the signal number.
|
|
|
|
If the supplied signal number is not within the range of valid
|
|
indices, then returns @code{NULL}.
|
|
|
|
The contents of the location pointed to are only guaranteed to be
|
|
valid until the next call to @code{strsigno}.
|
|
|
|
@end deftypefn
|
|
|
|
*/
|
|
|
|
const char *
|
|
strsigno (int signo)
|
|
{
|
|
const char *name;
|
|
static char buf[32];
|
|
|
|
if (signal_names == NULL)
|
|
{
|
|
init_signal_tables ();
|
|
}
|
|
|
|
if ((signo < 0) || (signo >= num_signal_names))
|
|
{
|
|
/* Out of range, just return NULL */
|
|
name = NULL;
|
|
}
|
|
else if ((signal_names == NULL) || (signal_names[signo] == NULL))
|
|
{
|
|
/* In range, but no signal_names or no entry at this index. */
|
|
sprintf (buf, "Signal %d", signo);
|
|
name = (const char *) buf;
|
|
}
|
|
else
|
|
{
|
|
/* In range, and a valid name. Just return the name. */
|
|
name = signal_names[signo];
|
|
}
|
|
|
|
return (name);
|
|
}
|
|
|
|
|
|
/*
|
|
|
|
@deftypefn Extension int strtosigno (const char *@var{name})
|
|
|
|
Given the symbolic name of a signal, map it to a signal number. If no
|
|
translation is found, returns 0.
|
|
|
|
@end deftypefn
|
|
|
|
*/
|
|
|
|
int
|
|
strtosigno (const char *name)
|
|
{
|
|
int signo = 0;
|
|
|
|
if (name != NULL)
|
|
{
|
|
if (signal_names == NULL)
|
|
{
|
|
init_signal_tables ();
|
|
}
|
|
for (signo = 0; signo < num_signal_names; signo++)
|
|
{
|
|
if ((signal_names[signo] != NULL) &&
|
|
(strcmp (name, signal_names[signo]) == 0))
|
|
{
|
|
break;
|
|
}
|
|
}
|
|
if (signo == num_signal_names)
|
|
{
|
|
signo = 0;
|
|
}
|
|
}
|
|
return (signo);
|
|
}
|
|
|
|
|
|
/*
|
|
|
|
@deftypefn Supplemental void psignal (int @var{signo}, char *@var{message})
|
|
|
|
Print @var{message} to the standard error, followed by a colon,
|
|
followed by the description of the signal specified by @var{signo},
|
|
followed by a newline.
|
|
|
|
@end deftypefn
|
|
|
|
*/
|
|
|
|
#ifndef HAVE_PSIGNAL
|
|
|
|
void
|
|
psignal (int signo, char *message)
|
|
{
|
|
if (signal_names == NULL)
|
|
{
|
|
init_signal_tables ();
|
|
}
|
|
if ((signo <= 0) || (signo >= sys_nsig))
|
|
{
|
|
fprintf (stderr, "%s: unknown signal\n", message);
|
|
}
|
|
else
|
|
{
|
|
fprintf (stderr, "%s: %s\n", message, sys_siglist[signo]);
|
|
}
|
|
}
|
|
|
|
#endif /* ! HAVE_PSIGNAL */
|
|
|
|
|
|
/* A simple little main that does nothing but print all the signal translations
|
|
if MAIN is defined and this file is compiled and linked. */
|
|
|
|
#ifdef MAIN
|
|
|
|
#include <stdio.h>
|
|
|
|
int
|
|
main (void)
|
|
{
|
|
int signo;
|
|
int maxsigno;
|
|
const char *name;
|
|
const char *msg;
|
|
|
|
maxsigno = signo_max ();
|
|
printf ("%d entries in names table.\n", num_signal_names);
|
|
printf ("%d entries in messages table.\n", sys_nsig);
|
|
printf ("%d is max useful index.\n", maxsigno);
|
|
|
|
/* Keep printing values until we get to the end of *both* tables, not
|
|
*either* table. Note that knowing the maximum useful index does *not*
|
|
relieve us of the responsibility of testing the return pointer for
|
|
NULL. */
|
|
|
|
for (signo = 0; signo <= maxsigno; signo++)
|
|
{
|
|
name = strsigno (signo);
|
|
name = (name == NULL) ? "<NULL>" : name;
|
|
msg = strsignal (signo);
|
|
msg = (msg == NULL) ? "<NULL>" : msg;
|
|
printf ("%-4d%-18s%s\n", signo, name, msg);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#endif
|