ruby/signal.c

1095 строки
21 KiB
C

/**********************************************************************
signal.c -
$Author$
$Date$
created at: Tue Dec 20 10:13:44 JST 1994
Copyright (C) 1993-2007 Yukihiro Matsumoto
Copyright (C) 2000 Network Applied Communication Laboratory, Inc.
Copyright (C) 2000 Information-technology Promotion Agency, Japan
**********************************************************************/
#include "ruby/ruby.h"
#include "ruby/signal.h"
#include "ruby/node.h"
#include "vm_core.h"
#include <signal.h>
#include <stdio.h>
#ifdef __BEOS__
#undef SIGBUS
#endif
#ifndef NSIG
# ifdef DJGPP
# define NSIG SIGMAX
# else
# define NSIG (_SIGMAX + 1) /* For QNX */
# endif
#endif
static struct signals {
const char *signm;
int signo;
} siglist [] = {
{"EXIT", 0},
#ifdef SIGHUP
{"HUP", SIGHUP},
#endif
{"INT", SIGINT},
#ifdef SIGQUIT
{"QUIT", SIGQUIT},
#endif
#ifdef SIGILL
{"ILL", SIGILL},
#endif
#ifdef SIGTRAP
{"TRAP", SIGTRAP},
#endif
#ifdef SIGIOT
{"IOT", SIGIOT},
#endif
#ifdef SIGABRT
{"ABRT", SIGABRT},
#endif
#ifdef SIGEMT
{"EMT", SIGEMT},
#endif
#ifdef SIGFPE
{"FPE", SIGFPE},
#endif
#ifdef SIGKILL
{"KILL", SIGKILL},
#endif
#ifdef SIGBUS
{"BUS", SIGBUS},
#endif
#ifdef SIGSEGV
{"SEGV", SIGSEGV},
#endif
#ifdef SIGSYS
{"SYS", SIGSYS},
#endif
#ifdef SIGPIPE
{"PIPE", SIGPIPE},
#endif
#ifdef SIGALRM
{"ALRM", SIGALRM},
#endif
#ifdef SIGTERM
{"TERM", SIGTERM},
#endif
#ifdef SIGURG
{"URG", SIGURG},
#endif
#ifdef SIGSTOP
{"STOP", SIGSTOP},
#endif
#ifdef SIGTSTP
{"TSTP", SIGTSTP},
#endif
#ifdef SIGCONT
{"CONT", SIGCONT},
#endif
#ifdef SIGCHLD
{"CHLD", SIGCHLD},
#endif
#ifdef SIGCLD
{"CLD", SIGCLD},
#else
# ifdef SIGCHLD
{"CLD", SIGCHLD},
# endif
#endif
#ifdef SIGTTIN
{"TTIN", SIGTTIN},
#endif
#ifdef SIGTTOU
{"TTOU", SIGTTOU},
#endif
#ifdef SIGIO
{"IO", SIGIO},
#endif
#ifdef SIGXCPU
{"XCPU", SIGXCPU},
#endif
#ifdef SIGXFSZ
{"XFSZ", SIGXFSZ},
#endif
#ifdef SIGVTALRM
{"VTALRM", SIGVTALRM},
#endif
#ifdef SIGPROF
{"PROF", SIGPROF},
#endif
#ifdef SIGWINCH
{"WINCH", SIGWINCH},
#endif
#ifdef SIGUSR1
{"USR1", SIGUSR1},
#endif
#ifdef SIGUSR2
{"USR2", SIGUSR2},
#endif
#ifdef SIGLOST
{"LOST", SIGLOST},
#endif
#ifdef SIGMSG
{"MSG", SIGMSG},
#endif
#ifdef SIGPWR
{"PWR", SIGPWR},
#endif
#ifdef SIGPOLL
{"POLL", SIGPOLL},
#endif
#ifdef SIGDANGER
{"DANGER", SIGDANGER},
#endif
#ifdef SIGMIGRATE
{"MIGRATE", SIGMIGRATE},
#endif
#ifdef SIGPRE
{"PRE", SIGPRE},
#endif
#ifdef SIGGRANT
{"GRANT", SIGGRANT},
#endif
#ifdef SIGRETRACT
{"RETRACT", SIGRETRACT},
#endif
#ifdef SIGSOUND
{"SOUND", SIGSOUND},
#endif
#ifdef SIGINFO
{"INFO", SIGINFO},
#endif
{NULL, 0}
};
static int
signm2signo(const char *nm)
{
struct signals *sigs;
for (sigs = siglist; sigs->signm; sigs++)
if (strcmp(sigs->signm, nm) == 0)
return sigs->signo;
return 0;
}
static const char*
signo2signm(int no)
{
struct signals *sigs;
for (sigs = siglist; sigs->signm; sigs++)
if (sigs->signo == no)
return sigs->signm;
return 0;
}
const char *
ruby_signal_name(int no)
{
return signo2signm(no);
}
/*
* call-seq:
* SignalException.new(sig) => signal_exception
*
* Construct a new SignalException object. +sig+ should be a known
* signal name, or a signal number.
*/
static VALUE
esignal_init(int argc, VALUE *argv, VALUE self)
{
int argnum = 1;
VALUE sig = Qnil;
int signo;
const char *signm;
if (argc > 0) {
sig = rb_check_to_integer(argv[0], "to_int");
if (!NIL_P(sig)) argnum = 2;
}
if (argc < 1 || argnum < argc) {
rb_raise(rb_eArgError, "wrong number of arguments (%d for %d)",
argc, argnum);
}
if (argnum == 2) {
signo = NUM2INT(sig);
if (signo < 0 || signo > NSIG) {
rb_raise(rb_eArgError, "invalid signal number (%d)", signo);
}
if (argc > 1) {
sig = argv[1];
}
else {
signm = signo2signm(signo);
if (signm) {
sig = rb_sprintf("SIG%s", signm);
}
else {
sig = rb_sprintf("SIG%u", signo);
}
}
}
else {
signm = SYMBOL_P(sig) ? rb_id2name(SYM2ID(sig)) : StringValuePtr(sig);
if (strncmp(signm, "SIG", 3) == 0) signm += 3;
signo = signm2signo(signm);
if (!signo) {
rb_raise(rb_eArgError, "unsupported name `SIG%s'", signm);
}
if (SYMBOL_P(sig)) {
sig = rb_str_new2(signm);
}
}
rb_call_super(1, &sig);
rb_iv_set(self, "signo", INT2NUM(signo));
return self;
}
static VALUE
interrupt_init(int argc, VALUE *argv, VALUE self)
{
VALUE args[2];
args[0] = INT2FIX(SIGINT);
rb_scan_args(argc, argv, "01", &args[1]);
return rb_call_super(2, args);
}
void
ruby_default_signal(int sig)
{
#ifndef MACOS_UNUSE_SIGNAL
signal(sig, SIG_DFL);
raise(sig);
#endif
}
/*
* call-seq:
* Process.kill(signal, pid, ...) => fixnum
*
* Sends the given signal to the specified process id(s), or to the
* current process if _pid_ is zero. _signal_ may be an
* integer signal number or a POSIX signal name (either with or without
* a +SIG+ prefix). If _signal_ is negative (or starts
* with a minus sign), kills process groups instead of
* processes. Not all signals are available on all platforms.
*
* pid = fork do
* Signal.trap("HUP") { puts "Ouch!"; exit }
* # ... do some work ...
* end
* # ...
* Process.kill("HUP", pid)
* Process.wait
*
* <em>produces:</em>
*
* Ouch!
*/
VALUE
rb_f_kill(int argc, VALUE *argv)
{
#ifndef HAS_KILLPG
#define killpg(pg, sig) kill(-(pg), sig)
#endif
int negative = 0;
int sig;
int i;
const char *s;
rb_secure(2);
if (argc < 2)
rb_raise(rb_eArgError, "wrong number of arguments -- kill(sig, pid...)");
switch (TYPE(argv[0])) {
case T_FIXNUM:
sig = FIX2INT(argv[0]);
break;
case T_SYMBOL:
s = rb_id2name(SYM2ID(argv[0]));
if (!s) rb_raise(rb_eArgError, "bad signal");
goto str_signal;
case T_STRING:
s = RSTRING_PTR(argv[0]);
if (s[0] == '-') {
negative++;
s++;
}
str_signal:
if (strncmp("SIG", s, 3) == 0)
s += 3;
if((sig = signm2signo(s)) == 0)
rb_raise(rb_eArgError, "unsupported name `SIG%s'", s);
if (negative)
sig = -sig;
break;
default:
{
VALUE str;
str = rb_check_string_type(argv[0]);
if (!NIL_P(str)) {
s = RSTRING_PTR(str);
goto str_signal;
}
rb_raise(rb_eArgError, "bad signal type %s",
rb_obj_classname(argv[0]));
}
break;
}
if (sig < 0) {
sig = -sig;
for (i=1; i<argc; i++) {
if (killpg(NUM2PIDT(argv[i]), sig) < 0)
rb_sys_fail(0);
}
}
else {
for (i=1; i<argc; i++) {
if (kill(NUM2PIDT(argv[i]), sig) < 0)
rb_sys_fail(0);
}
}
rb_thread_polling();
return INT2FIX(i-1);
}
static struct {
VALUE cmd;
} trap_list[NSIG];
static rb_atomic_t trap_pending_list[NSIG];
static char rb_trap_accept_nativethreads[NSIG];
rb_atomic_t rb_trap_pending;
rb_atomic_t rb_trap_immediate;
int rb_prohibit_interrupt = 1;
VALUE
rb_get_trap_cmd(int sig)
{
return trap_list[sig].cmd;
}
void
rb_gc_mark_trap_list(void)
{
#ifndef MACOS_UNUSE_SIGNAL
int i;
for (i=0; i<NSIG; i++) {
if (trap_list[i].cmd)
rb_gc_mark(trap_list[i].cmd);
}
#endif /* MACOS_UNUSE_SIGNAL */
}
#ifdef __dietlibc__
#define sighandler_t sh_t
#endif
typedef RETSIGTYPE (*sighandler_t)(int);
#ifdef POSIX_SIGNAL
static sighandler_t
ruby_signal(int signum, sighandler_t handler)
{
struct sigaction sigact, old;
rb_trap_accept_nativethreads[signum] = 0;
sigact.sa_handler = handler;
sigemptyset(&sigact.sa_mask);
sigact.sa_flags = 0;
#ifdef SA_NOCLDWAIT
if (signum == SIGCHLD && handler == SIG_IGN)
sigact.sa_flags |= SA_NOCLDWAIT;
#endif
sigaction(signum, &sigact, &old);
return old.sa_handler;
}
void
posix_signal(int signum, sighandler_t handler)
{
ruby_signal(signum, handler);
}
#else /* !POSIX_SIGNAL */
#define ruby_signal(sig,handler) (rb_trap_accept_nativethreads[sig] = 0, signal((sig),(handler)))
#ifdef HAVE_NATIVETHREAD
static sighandler_t
ruby_nativethread_signal(int signum, sighandler_t handler)
{
sighandler_t old;
old = signal(signum, handler);
rb_trap_accept_nativethreads[signum] = 1;
return old;
}
#endif
#endif
static RETSIGTYPE
sighandler(int sig)
{
rb_vm_t *vm = GET_VM(); /* fix me for Multi-VM */
ATOMIC_INC(vm->signal_buff[sig]);
ATOMIC_INC(vm->buffered_signal_size);
#if !defined(BSD_SIGNAL) && !defined(POSIX_SIGNAL)
ruby_signal(sig, sighandler);
#endif
}
# ifdef HAVE_SIGPROCMASK
static sigset_t trap_last_mask;
# else
static int trap_last_mask;
# endif
#if HAVE_PTHREAD_H
#include <pthread.h>
#endif
void
rb_disable_interrupt(void)
{
#ifndef _WIN32
sigset_t mask;
sigfillset(&mask);
sigdelset(&mask, SIGVTALRM);
sigdelset(&mask, SIGSEGV);
pthread_sigmask(SIG_SETMASK, &mask, NULL);
#endif
}
void
rb_enable_interrupt(void)
{
#ifndef _WIN32
sigset_t mask;
sigemptyset(&mask);
pthread_sigmask(SIG_SETMASK, &mask, NULL);
#endif
}
int
rb_get_next_signal(rb_vm_t *vm)
{
int i, sig = 0;
for (i=1; i<RUBY_NSIG; i++) {
if (vm->signal_buff[i] > 0) {
rb_disable_interrupt();
{
ATOMIC_DEC(vm->signal_buff[i]);
ATOMIC_DEC(vm->buffered_signal_size);
}
rb_enable_interrupt();
sig = i;
break;
}
}
return sig;
}
#ifdef SIGBUS
static RETSIGTYPE
sigbus(int sig)
{
rb_bug("Bus Error");
}
#endif
#ifdef SIGSEGV
static int segv_received = 0;
static RETSIGTYPE
sigsegv(int sig)
{
if (segv_received) {
fprintf(stderr, "SEGV recieved in SEGV handler\n");
exit(1);
}
else {
extern int ruby_gc_stress;
segv_received = 1;
ruby_gc_stress = 0;
rb_bug("Segmentation fault");
}
}
#endif
#ifdef SIGPIPE
static RETSIGTYPE
sigpipe(int sig)
{
/* do nothing */
}
#endif
static void
signal_exec(VALUE cmd, int sig)
{
rb_proc_t *proc;
VALUE signum = INT2FIX(sig);
GetProcPtr(cmd, proc);
vm_invoke_proc(GET_THREAD(), proc, proc->block.self, 1, &signum);
}
void
rb_trap_exit(void)
{
#ifndef MACOS_UNUSE_SIGNAL
if (trap_list[0].cmd) {
VALUE trap_exit = trap_list[0].cmd;
trap_list[0].cmd = 0;
signal_exec(trap_exit, 0);
}
#endif
}
void
rb_signal_exec(rb_thread_t *th, int sig)
{
VALUE cmd = rb_get_trap_cmd(sig);
if (cmd == 0) {
switch (sig) {
case SIGINT:
rb_interrupt();
break;
#ifdef SIGHUP
case SIGHUP:
#endif
#ifdef SIGQUIT
case SIGQUIT:
#endif
#ifdef SIGTERM
case SIGTERM:
#endif
#ifdef SIGALRM
case SIGALRM:
#endif
#ifdef SIGUSR1
case SIGUSR1:
#endif
#ifdef SIGUSR2
case SIGUSR2:
#endif
rb_thread_signal_raise(th, sig);
break;
}
}
else if (cmd == Qundef) {
rb_thread_signal_exit(th);
}
else {
signal_exec(cmd, sig);
}
}
void
rb_trap_exec(void)
{
#ifndef MACOS_UNUSE_SIGNAL
int i;
for (i=0; i<NSIG; i++) {
if (trap_pending_list[i]) {
trap_pending_list[i] = 0;
rb_signal_exec(GET_THREAD(), i);
}
}
#endif /* MACOS_UNUSE_SIGNAL */
rb_trap_pending = 0;
}
struct trap_arg {
#ifndef _WIN32
# ifdef HAVE_SIGPROCMASK
sigset_t mask;
# else
int mask;
# endif
#endif
int sig;
sighandler_t func;
VALUE cmd;
};
static sighandler_t
default_handler(int sig)
{
sighandler_t func;
switch (sig) {
case SIGINT:
#ifdef SIGHUP
case SIGHUP:
#endif
#ifdef SIGQUIT
case SIGQUIT:
#endif
#ifdef SIGTERM
case SIGTERM:
#endif
#ifdef SIGALRM
case SIGALRM:
#endif
#ifdef SIGUSR1
case SIGUSR1:
#endif
#ifdef SIGUSR2
case SIGUSR2:
#endif
func = sighandler;
break;
#ifdef SIGBUS
case SIGBUS:
func = sigbus;
break;
#endif
#ifdef SIGSEGV
case SIGSEGV:
func = sigsegv;
break;
#endif
#ifdef SIGPIPE
case SIGPIPE:
func = sigpipe;
break;
#endif
default:
func = SIG_DFL;
break;
}
return func;
}
static RETSIGTYPE
wrong_trap(int sig)
{
}
static sighandler_t
trap_handler(VALUE *cmd, int sig)
{
sighandler_t func = wrong_trap;
VALUE command;
if (NIL_P(*cmd)) {
func = SIG_IGN;
}
else {
command = rb_check_string_type(*cmd);
if (!NIL_P(command)) {
SafeStringValue(command); /* taint check */
switch (RSTRING_LEN(command)) {
case 0:
goto sig_ign;
break;
case 14:
if (strncmp(RSTRING_PTR(command), "SYSTEM_DEFAULT", 14) == 0) {
func = SIG_DFL;
*cmd = 0;
}
break;
case 7:
if (strncmp(RSTRING_PTR(command), "SIG_IGN", 7) == 0) {
sig_ign:
func = SIG_IGN;
*cmd = 0;
}
else if (strncmp(RSTRING_PTR(command), "SIG_DFL", 7) == 0) {
sig_dfl:
func = default_handler(sig);
*cmd = 0;
}
else if (strncmp(RSTRING_PTR(command), "DEFAULT", 7) == 0) {
goto sig_dfl;
}
break;
case 6:
if (strncmp(RSTRING_PTR(command), "IGNORE", 6) == 0) {
goto sig_ign;
}
break;
case 4:
if (strncmp(RSTRING_PTR(command), "EXIT", 4) == 0) {
func = sighandler;
*cmd = Qundef;
}
break;
}
if (func == wrong_trap) {
rb_raise(rb_eArgError, "wrong trap - %s", RSTRING_PTR(command));
}
}
else {
rb_proc_t *proc;
GetProcPtr(*cmd, proc);
func = sighandler;
}
}
return func;
}
static int
trap_signm(VALUE vsig)
{
int sig = -1;
const char *s;
switch (TYPE(vsig)) {
case T_FIXNUM:
sig = FIX2INT(vsig);
if (sig < 0 || sig >= NSIG) {
rb_raise(rb_eArgError, "invalid signal number (%d)", sig);
}
break;
case T_SYMBOL:
s = rb_id2name(SYM2ID(vsig));
if (!s) rb_raise(rb_eArgError, "bad signal");
goto str_signal;
default:
s = StringValuePtr(vsig);
str_signal:
if (strncmp("SIG", s, 3) == 0)
s += 3;
sig = signm2signo(s);
if (sig == 0 && strcmp(s, "EXIT") != 0)
rb_raise(rb_eArgError, "unsupported signal SIG%s", s);
}
#if defined(HAVE_SETITIMER)
if (sig == SIGVTALRM) {
rb_raise(rb_eArgError, "SIGVTALRM reserved for Thread; can't set handler");
}
#endif
return sig;
}
static VALUE
trap(struct trap_arg *arg)
{
sighandler_t oldfunc, func = arg->func;
VALUE oldcmd, command = arg->cmd;
int sig = arg->sig;
oldfunc = ruby_signal(sig, func);
oldcmd = trap_list[sig].cmd;
switch (oldcmd) {
case 0:
if (oldfunc == SIG_IGN) oldcmd = rb_str_new2("IGNORE");
else if (oldfunc == sighandler) oldcmd = rb_str_new2("DEFAULT");
else oldcmd = Qnil;
break;
case Qundef:
oldcmd = rb_str_new2("EXIT");
break;
}
trap_list[sig].cmd = command;
/* enable at least specified signal. */
#ifndef _WIN32
#ifdef HAVE_SIGPROCMASK
sigdelset(&arg->mask, sig);
#else
arg->mask &= ~sigmask(sig);
#endif
#endif
return oldcmd;
}
#ifndef _WIN32
static VALUE
trap_ensure(struct trap_arg *arg)
{
/* enable interrupt */
#ifdef HAVE_SIGPROCMASK
sigprocmask(SIG_SETMASK, &arg->mask, NULL);
#else
sigsetmask(arg->mask);
#endif
trap_last_mask = arg->mask;
return 0;
}
#endif
void
rb_trap_restore_mask(void)
{
#ifndef _WIN32
# ifdef HAVE_SIGPROCMASK
sigprocmask(SIG_SETMASK, &trap_last_mask, NULL);
# else
sigsetmask(trap_last_mask);
# endif
#endif
}
/*
* call-seq:
* Signal.trap( signal, command ) => obj
* Signal.trap( signal ) {| | block } => obj
*
* Specifies the handling of signals. The first parameter is a signal
* name (a string such as ``SIGALRM'', ``SIGUSR1'', and so on) or a
* signal number. The characters ``SIG'' may be omitted from the
* signal name. The command or block specifies code to be run when the
* signal is raised.
* If the command is the string ``IGNORE'' or ``SIG_IGN'', the signal
* will be ignored.
* If the command is ``DEFAULT'' or ``SIG_DFL'', the Ruby's default handler
* will be invoked.
* If the command is ``EXIT'', the script will be terminated by the signal.
* If the command is ``SYSTEM_DEFAULT'', the operating system's default
* handler will be invoked.
* Otherwise, the given command or block will be run.
* The special signal name ``EXIT'' or signal number zero will be
* invoked just prior to program termination.
* trap returns the previous handler for the given signal.
*
* Signal.trap(0, proc { puts "Terminating: #{$$}" })
* Signal.trap("CLD") { puts "Child died" }
* fork && Process.wait
*
* produces:
* Terminating: 27461
* Child died
* Terminating: 27460
*/
static VALUE
sig_trap(int argc, VALUE *argv)
{
struct trap_arg arg;
rb_secure(2);
if (argc == 0 || argc > 2) {
rb_raise(rb_eArgError, "wrong number of arguments -- trap(sig, cmd)/trap(sig){...}");
}
arg.sig = trap_signm(argv[0]);
if (argc == 1) {
arg.cmd = rb_block_proc();
arg.func = sighandler;
}
else if (argc == 2) {
arg.cmd = argv[1];
arg.func = trap_handler(&arg.cmd, arg.sig);
}
if (OBJ_TAINTED(arg.cmd)) {
rb_raise(rb_eSecurityError, "Insecure: tainted signal trap");
}
#ifndef _WIN32
/* disable interrupt */
# ifdef HAVE_SIGPROCMASK
sigfillset(&arg.mask);
sigprocmask(SIG_BLOCK, &arg.mask, &arg.mask);
# else
arg.mask = sigblock(~0);
# endif
return rb_ensure(trap, (VALUE)&arg, trap_ensure, (VALUE)&arg);
#else
return trap(&arg);
#endif
}
/*
* call-seq:
* Signal.list => a_hash
*
* Returns a list of signal names mapped to the corresponding
* underlying signal numbers.
*
* Signal.list #=> {"ABRT"=>6, "ALRM"=>14, "BUS"=>7, "CHLD"=>17, "CLD"=>17, "CONT"=>18, "FPE"=>8, "HUP"=>1, "ILL"=>4, "INT"=>2, "IO"=>29, "IOT"=>6, "KILL"=>9, "PIPE"=>13, "POLL"=>29, "PROF"=>27, "PWR"=>30, "QUIT"=>3, "SEGV"=>11, "STOP"=>19, "SYS"=>31, "TERM"=>15, "TRAP"=>5, "TSTP"=>20, "TTIN"=>21, "TTOU"=>22, "URG"=>23, "USR1"=>10, "USR2"=>12, "VTALRM"=>26, "WINCH"=>28, "XCPU"=>24, "XFSZ"=>25}
*/
static VALUE
sig_list(void)
{
VALUE h = rb_hash_new();
struct signals *sigs;
for (sigs = siglist; sigs->signm; sigs++) {
rb_hash_aset(h, rb_str_new2(sigs->signm), INT2FIX(sigs->signo));
}
return h;
}
static void
install_sighandler(int signum, sighandler_t handler)
{
sighandler_t old;
old = ruby_signal(signum, handler);
if (old != SIG_DFL) {
ruby_signal(signum, old);
}
}
static void
init_sigchld(int sig)
{
sighandler_t oldfunc;
#ifndef _WIN32
# ifdef HAVE_SIGPROCMASK
sigset_t mask;
# else
int mask;
# endif
#endif
#ifndef _WIN32
/* disable interrupt */
# ifdef HAVE_SIGPROCMASK
sigfillset(&mask);
sigprocmask(SIG_BLOCK, &mask, &mask);
# else
mask = sigblock(~0);
# endif
#endif
oldfunc = ruby_signal(sig, SIG_DFL);
if (oldfunc != SIG_DFL && oldfunc != SIG_IGN) {
ruby_signal(sig, oldfunc);
} else {
trap_list[sig].cmd = 0;
}
#ifndef _WIN32
#ifdef HAVE_SIGPROCMASK
sigdelset(&mask, sig);
sigprocmask(SIG_SETMASK, &mask, NULL);
#else
mask &= ~sigmask(sig);
sigsetmask(mask);
#endif
trap_last_mask = mask;
#endif
}
#ifdef RUBY_DEBUG_ENV
int ruby_enable_coredump = 0;
#endif
/*
* Many operating systems allow signals to be sent to running
* processes. Some signals have a defined effect on the process, while
* others may be trapped at the code level and acted upon. For
* example, your process may trap the USR1 signal and use it to toggle
* debugging, and may use TERM to initiate a controlled shutdown.
*
* pid = fork do
* Signal.trap("USR1") do
* $debug = !$debug
* puts "Debug now: #$debug"
* end
* Signal.trap("TERM") do
* puts "Terminating..."
* shutdown()
* end
* # . . . do some work . . .
* end
*
* Process.detach(pid)
*
* # Controlling program:
* Process.kill("USR1", pid)
* # ...
* Process.kill("USR1", pid)
* # ...
* Process.kill("TERM", pid)
*
* produces:
* Debug now: true
* Debug now: false
* Terminating...
*
* The list of available signal names and their interpretation is
* system dependent. Signal delivery semantics may also vary between
* systems; in particular signal delivery may not always be reliable.
*/
void
Init_signal(void)
{
#ifndef MACOS_UNUSE_SIGNAL
VALUE mSignal = rb_define_module("Signal");
rb_define_global_function("trap", sig_trap, -1);
rb_define_module_function(mSignal, "trap", sig_trap, -1);
rb_define_module_function(mSignal, "list", sig_list, 0);
rb_define_method(rb_eSignal, "initialize", esignal_init, -1);
rb_attr(rb_eSignal, rb_intern("signo"), 1, 0, 0);
rb_alias(rb_eSignal, rb_intern("signm"), rb_intern("message"));
rb_define_method(rb_eInterrupt, "initialize", interrupt_init, -1);
install_sighandler(SIGINT, sighandler);
#ifdef SIGHUP
install_sighandler(SIGHUP, sighandler);
#endif
#ifdef SIGQUIT
install_sighandler(SIGQUIT, sighandler);
#endif
#ifdef SIGTERM
install_sighandler(SIGTERM, sighandler);
#endif
#ifdef SIGALRM
install_sighandler(SIGALRM, sighandler);
#endif
#ifdef SIGUSR1
install_sighandler(SIGUSR1, sighandler);
#endif
#ifdef SIGUSR2
install_sighandler(SIGUSR2, sighandler);
#endif
#ifdef RUBY_DEBUG_ENV
if (!ruby_enable_coredump)
#endif
{
#ifdef SIGBUS
install_sighandler(SIGBUS, sigbus);
#endif
#ifdef SIGSEGV
install_sighandler(SIGSEGV, sigsegv);
#endif
}
#ifdef SIGPIPE
install_sighandler(SIGPIPE, sigpipe);
#endif
#if defined(SIGCLD)
init_sigchld(SIGCLD);
#elif defined(SIGCHLD)
init_sigchld(SIGCHLD);
#endif
#endif /* MACOS_UNUSE_SIGNAL */
}