libbb: introduce bb_signals and bb_signals_recursive,

which sets same handler for many signals. sig_catch is nuked
(bb_signals_recursive is more descriptive name).
*: use them as appropriate. 

function                                             old     new   delta
bb_signals_recursive                                   -      95     +95
bb_signals                                             -      52     +52
run_command                                          258     273     +15
svlogd_main                                         1368    1377      +9
runsv_main                                          1746    1752      +6
runsvdir_main                                       1643    1646      +3
UNSPEC_print                                          64      66      +2
time_main                                           1128    1127      -1
...
resize_main                                          246     210     -36
sig_catch                                             63       -     -63
set_fatal_sighandler                                  85      14     -71
------------------------------------------------------------------------------
(add/remove: 2/1 grow/shrink: 5/24 up/down: 182/-548)        Total: -366 bytes

console-tools/resize.c

@@ -37,10 +37,12 @@ int resize_main(int argc, char **argv)
 	new = old_termios;
 	new.c_cflag |= (CLOCAL | CREAD);
 	new.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG);
-	signal(SIGINT, onintr);
-	signal(SIGQUIT, onintr);
-	signal(SIGTERM, onintr);
-	signal(SIGALRM, onintr);
+	bb_signals(0
+		+ (1 << SIGINT)
+		+ (1 << SIGQUIT)
+		+ (1 << SIGTERM)
+		+ (1 << SIGALRM)
+		, onintr);
 	tcsetattr(STDERR_FILENO, TCSANOW, &new);
 
 	/* save_cursor_pos 7

coreutils/tee.c

@@ -36,12 +36,12 @@ int tee_main(int argc, char **argv)
 	mode += (retval & 2);	/* Since 'a' is the 2nd option... */
 
 	if (retval & 1) {
-		signal(SIGINT, SIG_IGN); /* TODO - switch to sigaction. */
+		signal(SIGINT, SIG_IGN); /* TODO - switch to sigaction. (why?) */
 	}
 	retval = EXIT_SUCCESS;
 	/* gnu tee ignores SIGPIPE in case one of the output files is a pipe
 	 * that doesn't consume all its input.  Good idea... */
-	signal(SIGPIPE, SIG_IGN);	/* TODO - switch to sigaction. */
+	signal(SIGPIPE, SIG_IGN);
 
 	/* Allocate an array of FILE *'s, with one extra for a sentinal. */
 	fp = files = xzalloc(sizeof(FILE *) * (argc + 2));

include/libbb.h

@@ -274,14 +274,18 @@ char *xrealloc_getcwd_or_warn(char *cwd);
 
 char *xmalloc_follow_symlinks(const char *path);
 
-//TODO: signal(sid, f) is the same? then why?
-extern void sig_catch(int,void (*)(int));
-//#define sig_ignore(s) (sig_catch((s), SIG_IGN))
-//#define sig_uncatch(s) (sig_catch((s), SIG_DFL))
-extern void sig_block(int);
-extern void sig_unblock(int);
-/* UNUSED: extern void sig_blocknone(void); */
-extern void sig_pause(void);
+//enum {
+//	BB_SIGS_FATAL = ,
+//};
+void bb_signals(int sigs, void (*f)(int));
+/* Unlike signal() and bb_signals, sets handler with sigaction()
+ * and in a way that while signal handler is run, no other signals
+ * will be blocked: */
+void bb_signals_recursive(int sigs, void (*f)(int));
+void sig_block(int);
+void sig_unblock(int);
+/* UNUSED: void sig_blocknone(void); */
+void sig_pause(void);
 
 
 void xsetgid(gid_t gid);

init/init.c

@@ -319,15 +319,17 @@ static pid_t run(const struct init_action *a)
 	/* Child */
 
 	/* Reset signal handlers that were set by the parent process */
-	signal(SIGUSR1, SIG_DFL);
-	signal(SIGUSR2, SIG_DFL);
-	signal(SIGINT, SIG_DFL);
-	signal(SIGTERM, SIG_DFL);
-	signal(SIGHUP, SIG_DFL);
-	signal(SIGQUIT, SIG_DFL);
-	signal(SIGCONT, SIG_DFL);
-	signal(SIGSTOP, SIG_DFL);
-	signal(SIGTSTP, SIG_DFL);
+	bb_signals(0
+		+ (1 << SIGUSR1)
+		+ (1 << SIGUSR2)
+		+ (1 << SIGINT)
+		+ (1 << SIGTERM)
+		+ (1 << SIGHUP)
+		+ (1 << SIGQUIT)
+		+ (1 << SIGCONT)
+		+ (1 << SIGSTOP)
+		+ (1 << SIGTSTP)
+		, SIG_DFL);
 
 	/* Create a new session and make ourself the process
 	 * group leader */
@@ -349,9 +351,11 @@ static pid_t run(const struct init_action *a)
 
 		if (pid > 0) {
 			/* Parent - wait till the child is done */
-			signal(SIGINT, SIG_IGN);
-			signal(SIGTSTP, SIG_IGN);
-			signal(SIGQUIT, SIG_IGN);
+			bb_signals(0
+				+ (1 << SIGINT)
+				+ (1 << SIGTSTP)
+				+ (1 << SIGQUIT)
+				, SIG_IGN);
 			signal(SIGCHLD, SIG_DFL);
 
 			waitfor(pid);
@@ -864,15 +868,21 @@ int init_main(int argc, char **argv)
 		}
 		/* Set up sig handlers  -- be sure to
 		 * clear all of these in run() */
-		signal(SIGHUP, exec_restart_action);
-		signal(SIGQUIT, exec_restart_action);
-		signal(SIGUSR1, halt_reboot_pwoff); /* halt */
-		signal(SIGUSR2, halt_reboot_pwoff); /* poweroff */
-		signal(SIGTERM, halt_reboot_pwoff); /* reboot */
+		bb_signals(0
+			+ (1 << SIGHUP)
+			+ (1 << SIGQUIT)
+			, exec_restart_action);
+		bb_signals(0
+			+ (1 << SIGUSR1)  /* halt */
+			+ (1 << SIGUSR2)  /* poweroff */
+			+ (1 << SIGTERM)  /* reboot */
+			, halt_reboot_pwoff);
 		signal(SIGINT, ctrlaltdel_signal);
 		signal(SIGCONT, cont_handler);
-		signal(SIGSTOP, stop_handler);
-		signal(SIGTSTP, stop_handler);
+		bb_signals(0
+			+ (1 << SIGSTOP)
+			+ (1 << SIGTSTP)
+			, stop_handler);
 
 		/* Turn off rebooting via CTL-ALT-DEL -- we get a
 		 * SIGINT on CAD so we can shut things down gracefully... */

libbb/Kbuild

@@ -78,6 +78,7 @@ lib-y += safe_strncpy.o
 lib-y += safe_write.o
 lib-y += setup_environment.o
 lib-y += sha1.o
+lib-y += signals.o
 lib-y += simplify_path.o
 lib-y += skip_whitespace.o
 lib-y += speed_table.o

libbb/signals.c

@@ -0,0 +1,80 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ * Copyright (C) 2006 Rob Landley
+ * Copyright (C) 2006 Denis Vlasenko
+ *
+ * Licensed under GPL version 2, see file LICENSE in this tarball for details.
+ */
+
+#include "libbb.h"
+
+void bb_signals(int sigs, void (*f)(int))
+{
+	int sig_no = 0;
+	int bit = 1;
+
+	while (sigs) {
+		if (sigs & bit) {
+			sigs &= ~bit;
+			signal(sig_no, f);
+		}
+		sig_no++;
+		bit <<= 1;
+	}
+}
+
+void bb_signals_recursive(int sigs, void (*f)(int))
+{
+	int sig_no = 0;
+	int bit = 1;
+	struct sigaction sa;
+
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = f;
+	/*sa.sa_flags = 0;*/
+	/*sigemptyset(&sa.sa_mask); - hope memset did it*/
+
+	while (sigs) {
+		if (sigs & bit) {
+			sigs &= ~bit;
+			sigaction(sig_no, &sa, NULL);
+		}
+		sig_no++;
+		bit <<= 1;
+	}
+}
+
+void sig_block(int sig)
+{
+	sigset_t ss;
+	sigemptyset(&ss);
+	sigaddset(&ss, sig);
+	sigprocmask(SIG_BLOCK, &ss, NULL);
+}
+
+void sig_unblock(int sig)
+{
+	sigset_t ss;
+	sigemptyset(&ss);
+	sigaddset(&ss, sig);
+	sigprocmask(SIG_UNBLOCK, &ss, NULL);
+}
+
+#if 0
+void sig_blocknone(void)
+{
+	sigset_t ss;
+	sigemptyset(&ss);
+	sigprocmask(SIG_SETMASK, &ss, NULL);
+}
+#endif
+
+void sig_pause(void)
+{
+	sigset_t ss;
+	sigemptyset(&ss);
+	sigsuspend(&ss);
+}

libbb/xfuncs.c

@@ -234,48 +234,6 @@ void xfflush_stdout(void)
 	}
 }
 
-void sig_block(int sig)
-{
-	sigset_t ss;
-	sigemptyset(&ss);
-	sigaddset(&ss, sig);
-	sigprocmask(SIG_BLOCK, &ss, NULL);
-}
-
-void sig_unblock(int sig)
-{
-	sigset_t ss;
-	sigemptyset(&ss);
-	sigaddset(&ss, sig);
-	sigprocmask(SIG_UNBLOCK, &ss, NULL);
-}
-
-#if 0
-void sig_blocknone(void)
-{
-	sigset_t ss;
-	sigemptyset(&ss);
-	sigprocmask(SIG_SETMASK, &ss, NULL);
-}
-#endif
-
-void sig_catch(int sig, void (*f)(int))
-{
-	struct sigaction sa;
-	sa.sa_handler = f;
-	sa.sa_flags = 0;
-	sigemptyset(&sa.sa_mask);
-	sigaction(sig, &sa, NULL);
-}
-
-void sig_pause(void)
-{
-	sigset_t ss;
-	sigemptyset(&ss);
-	sigsuspend(&ss);
-}
-
-
 void xsetenv(const char *key, const char *value)
 {
 	if (setenv(key, value, 1))

loginutils/passwd.c

@@ -171,9 +171,11 @@ int passwd_main(int argc, char **argv)
 
 	rlimit_fsize.rlim_cur = rlimit_fsize.rlim_max = 512L * 30000;
 	setrlimit(RLIMIT_FSIZE, &rlimit_fsize);
-	signal(SIGHUP, SIG_IGN);
-	signal(SIGINT, SIG_IGN);
-	signal(SIGQUIT, SIG_IGN);
+	bb_signals(0
+		+ (1 << SIGHUP)
+		+ (1 << SIGINT)
+		+ (1 << SIGQUIT)
+		, SIG_IGN);
 	umask(077);
 	xsetuid(0);
 

miscutils/less.c

@@ -1355,8 +1355,10 @@ int less_main(int argc, char **argv)
 		empty_line_marker = "";
 
 	tcgetattr(kbd_fd, &term_orig);
-	signal(SIGTERM, sig_catcher);
-	signal(SIGINT, sig_catcher);
+	bb_signals(0
+		+ (1 << SIGTERM)
+		+ (1 << SIGINT)
+		, sig_catcher);
 	term_less = term_orig;
 	term_less.c_lflag &= ~(ICANON | ECHO);
 	term_less.c_iflag &= ~(IXON | ICRNL);

miscutils/microcom.c

@@ -99,10 +99,12 @@ int microcom_main(int argc, char **argv)
 	}
 
 	// setup signals
-	sig_catch(SIGHUP,  signal_handler);
-	sig_catch(SIGINT,  signal_handler);
-	sig_catch(SIGTERM, signal_handler);
-	sig_catch(SIGPIPE, signal_handler);
+	bb_signals_recursive(0
+			+ (1 << SIGHUP)
+			+ (1 << SIGINT)
+			+ (1 << SIGTERM)
+			+ (1 << SIGPIPE)
+			, signal_handler);
 
 	// error exit code if we fail to open the device
 	signalled = 1;

miscutils/time.c

@@ -61,7 +61,7 @@ static const char long_format[] ALIGN1 =
    Return 0 on error, 1 if ok.  */
 
 /* pid_t is short on BSDI, so don't try to promote it.  */
-static int resuse_end(pid_t pid, resource_t * resp)
+static int resuse_end(pid_t pid, resource_t *resp)
 {
 	int status;
 	pid_t caught;
@@ -69,7 +69,7 @@ static int resuse_end(pid_t pid, resource_t * resp)
 	/* Ignore signals, but don't ignore the children.  When wait3
 	   returns the child process, set the time the command finished. */
 	while ((caught = wait3(&status, 0, &resp->ru)) != pid) {
-		if (caught == -1)
+		if (caught == -1 && errno != EINTR)
 			return 0;
 	}
 	resp->elapsed_ms = (monotonic_us() / 1000) - resp->elapsed_ms;
@@ -373,24 +373,26 @@ static void summarize(const char *fmt, char **command, resource_t * resp)
 
 /* Run command CMD and return statistics on it.
    Put the statistics in *RESP.  */
-static void run_command(char *const *cmd, resource_t * resp)
+static void run_command(char *const *cmd, resource_t *resp)
 {
 	pid_t pid;			/* Pid of child.  */
-	__sighandler_t interrupt_signal, quit_signal;
+	void (*interrupt_signal)(int);
+	void (*quit_signal)(int);
 
 	resp->elapsed_ms = monotonic_us() / 1000;
 	pid = vfork();		/* Run CMD as child process.  */
 	if (pid < 0)
 		bb_error_msg_and_die("cannot fork");
-	else if (pid == 0) {	/* If child.  */
+	if (pid == 0) {	/* If child.  */
 		/* Don't cast execvp arguments; that causes errors on some systems,
 		   versus merely warnings if the cast is left off.  */
 		BB_EXECVP(cmd[0], cmd);
-		bb_error_msg("cannot run %s", cmd[0]);
-		_exit(errno == ENOENT ? 127 : 126);
+		xfunc_error_retval = (errno == ENOENT ? 127 : 126);
+		bb_error_msg_and_die("cannot run %s", cmd[0]);
 	}
 
 	/* Have signals kill the child but not self (if possible).  */
+//TODO: just block all sigs? and reenable them in the very end in main?
 	interrupt_signal = signal(SIGINT, SIG_IGN);
 	quit_signal = signal(SIGQUIT, SIG_IGN);
 

miscutils/watchdog.c

@@ -47,8 +47,10 @@ int watchdog_main(int argc, char **argv)
 		bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv);
 	}
 
-	signal(SIGHUP, watchdog_shutdown);
-	signal(SIGINT, watchdog_shutdown);
+	bb_signals(0
+		+ (1 << SIGHUP)
+		+ (1 << SIGINT)
+		, watchdog_shutdown);
 
 	/* Use known fd # - avoid needing global 'int fd' */
 	xmove_fd(xopen(argv[argc - 1], O_WRONLY), 3);

networking/dnsd.c

@@ -361,14 +361,16 @@ int dnsd_main(int argc, char **argv)
 	dnsentryinit();
 
 	signal(SIGINT, interrupt);
-	/* why? signal(SIGPIPE, SIG_IGN); */
-	signal(SIGHUP, SIG_IGN);
+	bb_signals(0
+		/* why? + (1 << SIGPIPE) */
+		+ (1 << SIGHUP)
 #ifdef SIGTSTP
-	signal(SIGTSTP, SIG_IGN);
+		+ (1 << SIGTSTP)
 #endif
 #ifdef SIGURG
-	signal(SIGURG, SIG_IGN);
+		+ (1 << SIGURG)
 #endif
+		, SIG_IGN);
 
 	lsa = xdotted2sockaddr(listen_interface, port);
 	udps = xsocket(lsa->u.sa.sa_family, SOCK_DGRAM, 0);

networking/nc_bloaty.c

@@ -683,14 +683,18 @@ int nc_main(int argc, char **argv)
 	PTR_TO_GLOBALS = xzalloc(sizeof(G));
 
 	/* catch a signal or two for cleanup */
-	signal(SIGINT, catch);
-	signal(SIGQUIT, catch);
-	signal(SIGTERM, catch);
+	bb_signals(0
+		+ (1 << SIGINT)
+		+ (1 << SIGQUIT)
+		+ (1 << SIGTERM)
+		, catch);
 	/* and suppress others... */
+	bb_signals(0
 #ifdef SIGURG
-	signal(SIGURG, SIG_IGN);
+		+ (1 << SIGURG)
 #endif
-	signal(SIGPIPE, SIG_IGN); /* important! */
+		+ (1 << SIGPIPE) /* important! */
+		, SIG_IGN);
 
 	proggie = argv;
 	while (*++proggie) {

networking/sendmail.c

@@ -111,8 +111,10 @@ static void launch_helper(const char **argv)
 		_exit(127);
 	}
 	// parent - check whether child is alive
-	sig_catch(SIGCHLD, signal_handler);
-	sig_catch(SIGALRM, signal_handler);
+	bb_signals_recursive(0
+			+ (1 << SIGCHLD)
+			+ (1 << SIGALRM)
+			, signal_handler);
 	signal_handler(SIGCHLD);
 	// child seems OK -> parent goes on
 }

networking/slattach.c

@@ -175,10 +175,12 @@ int slattach_main(int argc, char **argv)
 
 	/* Trap signals in order to restore tty states upon exit */
 	if (!(opt & OPT_e_quit)) {
-		signal(SIGHUP, sig_handler);
-		signal(SIGINT, sig_handler);
-		signal(SIGQUIT, sig_handler);
-		signal(SIGTERM, sig_handler);
+		bb_signals(0
+			+ (1 << SIGHUP)
+			+ (1 << SIGINT)
+			+ (1 << SIGQUIT)
+			+ (1 << SIGTERM)
+			, sig_handler);
 	}
 
 	/* Open tty */

networking/telnetd.c

@@ -279,8 +279,7 @@ make_new_session(
 	setsid();
 
 	/* Restore default signal handling */
-	signal(SIGCHLD, SIG_DFL);
-	signal(SIGPIPE, SIG_DFL);
+	bb_signals((1 << SIGCHLD) + (1 << SIGPIPE), SIG_DFL);
 
 	/* open the child's side of the tty. */
 	/* NB: setsid() disconnects from any previous ctty's. Therefore

networking/udhcp/signalpipe.c

@@ -42,9 +42,11 @@ void udhcp_sp_setup(void)
 	close_on_exec_on(signal_pipe.rd);
 	close_on_exec_on(signal_pipe.wr);
 	ndelay_on(signal_pipe.wr);
-	signal(SIGUSR1, signal_handler);
-	signal(SIGUSR2, signal_handler);
-	signal(SIGTERM, signal_handler);
+	bb_signals(0
+		+ (1 << SIGUSR1)
+		+ (1 << SIGUSR2)
+		+ (1 << SIGTERM)
+		, signal_handler);
 }
 
 

procps/top.c

@@ -772,8 +772,10 @@ int top_main(int argc, char **argv)
 	/* unbuffered input, turn off echo */
 	new_settings.c_lflag &= ~(ISIG | ICANON | ECHO | ECHONL);
 
-	signal(SIGTERM, sig_catcher);
-	signal(SIGINT, sig_catcher);
+	bb_signals(0
+		+ (1 << SIGTERM)
+		+ (1 << SIGINT)
+		, sig_catcher);
 	tcsetattr(0, TCSANOW, (void *) &new_settings);
 	atexit(reset_term);
 #endif /* FEATURE_USE_TERMIOS */

runit/runsv.c

@@ -345,8 +345,10 @@ static void startservice(struct svdir *s)
 				xdup2(logpipe.wr, 1);
 			}
 		}
-		signal(SIGCHLD, SIG_DFL);
-		signal(SIGTERM, SIG_DFL);
+		bb_signals(0
+			+ (1 << SIGCHLD)
+			+ (1 << SIGTERM)
+			, SIG_DFL);
 		sig_unblock(SIGCHLD);
 		sig_unblock(SIGTERM);
 		execvp(*run, run);
@@ -460,9 +462,9 @@ int runsv_main(int argc, char **argv)
 	ndelay_on(selfpipe.wr);
 
 	sig_block(SIGCHLD);
-	sig_catch(SIGCHLD, s_child);
+	bb_signals_recursive(1 << SIGCHLD, s_child);
 	sig_block(SIGTERM);
-	sig_catch(SIGTERM, s_term);
+	bb_signals_recursive(1 << SIGTERM, s_term);
 
 	xchdir(dir);
 	/* bss: svd[0].pid = 0; */

runit/runsvdir.c

@@ -100,8 +100,10 @@ static void runsv(int no, const char *name)
 		/* child */
 		if (set_pgrp)
 			setsid();
-		signal(SIGHUP, SIG_DFL);
-		signal(SIGTERM, SIG_DFL);
+		bb_signals(0
+			+ (1 << SIGHUP)
+			+ (1 << SIGTERM)
+			, SIG_DFL);
 		execvp(prog[0], prog);
 		fatal2_cannot("start runsv ", name);
 	}
@@ -232,8 +234,8 @@ int runsvdir_main(int argc, char **argv)
 			bb_show_usage();
 	}
 
-	sig_catch(SIGTERM, s_term);
-	sig_catch(SIGHUP, s_hangup);
+	bb_signals_recursive(1 << SIGTERM, s_term);
+	bb_signals_recursive(1 << SIGHUP, s_hangup);
 	svdir = *argv++;
 	if (argv && *argv) {
 		rplog = *argv;

runit/svlogd.c

@@ -222,9 +222,11 @@ static unsigned processorstart(struct logdir *ld)
 		int fd;
 
 		/* child */
-		signal(SIGTERM, SIG_DFL);
-		signal(SIGALRM, SIG_DFL);
-		signal(SIGHUP, SIG_DFL);
+		bb_signals(0
+			+ (1 << SIGTERM)
+			+ (1 << SIGALRM)
+			+ (1 << SIGHUP)
+			, SIG_DFL);
 		sig_unblock(SIGTERM);
 		sig_unblock(SIGALRM);
 		sig_unblock(SIGHUP);
@@ -903,10 +905,10 @@ int svlogd_main(int argc, char **argv)
 	sigaddset(&blocked_sigset, SIGALRM);
 	sigaddset(&blocked_sigset, SIGHUP);
 	sigprocmask(SIG_BLOCK, &blocked_sigset, NULL);
-	sig_catch(SIGTERM, sig_term_handler);
-	sig_catch(SIGCHLD, sig_child_handler);
-	sig_catch(SIGALRM, sig_alarm_handler);
-	sig_catch(SIGHUP, sig_hangup_handler);
+	bb_signals_recursive(1 << SIGTERM, sig_term_handler);
+	bb_signals_recursive(1 << SIGCHLD, sig_child_handler);
+	bb_signals_recursive(1 << SIGALRM, sig_alarm_handler);
+	bb_signals_recursive(1 << SIGHUP, sig_hangup_handler);
 
 	logdirs_reopen();
 

shell/hush.c

@@ -709,28 +709,34 @@ static void signal_SA_RESTART(int sig, void (*handler)(int))
 /* Signals are grouped, we handle them in batches */
 static void set_fatal_sighandler(void (*handler)(int))
 {
-	signal(SIGILL , handler);
-	signal(SIGTRAP, handler);
-	signal(SIGABRT, handler);
-	signal(SIGFPE , handler);
-	signal(SIGBUS , handler);
-	signal(SIGSEGV, handler);
+	bb_signals(0
+		+ (1 << SIGILL)
+		+ (1 << SIGTRAP)
+		+ (1 << SIGABRT)
+		+ (1 << SIGFPE)
+		+ (1 << SIGBUS)
+		+ (1 << SIGSEGV)
 	/* bash 3.2 seems to handle these just like 'fatal' ones */
-	signal(SIGHUP , handler);
-	signal(SIGPIPE, handler);
-	signal(SIGALRM, handler);
+		+ (1 << SIGHUP)
+		+ (1 << SIGPIPE)
+		+ (1 << SIGALRM)
+		, handler);
 }
 static void set_jobctrl_sighandler(void (*handler)(int))
 {
-	signal(SIGTSTP, handler);
-	signal(SIGTTIN, handler);
-	signal(SIGTTOU, handler);
+	bb_signals(0
+		+ (1 << SIGTSTP)
+		+ (1 << SIGTTIN)
+		+ (1 << SIGTTOU)
+		, handler);
 }
 static void set_misc_sighandler(void (*handler)(int))
 {
-	signal(SIGINT , handler);
-	signal(SIGQUIT, handler);
-	signal(SIGTERM, handler);
+	bb_signals(0
+		+ (1 << SIGINT)
+		+ (1 << SIGQUIT)
+		+ (1 << SIGTERM)
+		, handler);
 }
 /* SIGCHLD is special and handled separately */
 

sysklogd/klogd.c

@@ -57,9 +57,10 @@ int klogd_main(int argc, char **argv)
 	openlog("kernel", 0, LOG_KERN);
 
 	/* Set up sig handlers */
-	signal(SIGINT, klogd_signal);
-	signal(SIGKILL, klogd_signal);
-	signal(SIGTERM, klogd_signal);
+	bb_signals(0
+		+ (1 << SIGINT)
+		+ (1 << SIGTERM)
+		, klogd_signal);
 	signal(SIGHUP, SIG_IGN);
 
 	/* "Open the log. Currently a NOP." */

sysklogd/syslogd.c

@@ -540,9 +540,11 @@ static void do_syslogd(void)
 	int sock_fd;
 
 	/* Set up signal handlers */
-	signal(SIGINT, quit_signal);
-	signal(SIGTERM, quit_signal);
-	signal(SIGQUIT, quit_signal);
+	bb_signals(0
+		+ (1 << SIGINT)
+		+ (1 << SIGTERM)
+		+ (1 << SIGQUIT)
+		, quit_signal);
 	signal(SIGHUP, SIG_IGN);
 	/* signal(SIGCHLD, SIG_IGN); - why? */
 #ifdef SYSLOGD_MARK

util-linux/more.c

@@ -87,9 +87,11 @@ int more_main(int argc, char **argv)
 	new_settings.c_cc[VMIN] = 1;
 	new_settings.c_cc[VTIME] = 0;
 	setTermSettings(cin_fileno, &new_settings);
-	signal(SIGINT, gotsig);
-	signal(SIGQUIT, gotsig);
-	signal(SIGTERM, gotsig);
+	bb_signals(0
+		+ (1 << SIGINT)
+		+ (1 << SIGQUIT)
+		+ (1 << SIGTERM)
+		, gotsig);
 #endif
 
 	do {