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

1 files changed, 9 insertions, 7 deletions

diff --git a/runit/svlogd.c b/runit/svlogd.c
index 9c169da1f..73570dad0 100644
--- a/runit/svlogd.c
+++ b/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();