hush: replace signal handling machinery

With new version of signal handling, read builtin should be less buggy
wrt signals.

function                                             old     new   delta
install_sighandlers                                    -     121    +121
switch_off_special_sigs                                -      84     +84
pick_sighandler                                        -      58     +58
install_special_sighandlers                            -      47     +47
builtin_wait                                         284     319     +35
record_pending_signo                                   -      21     +21
execvp_or_die                                         43      48      +5
file_get                                             290     288      -2
run_list                                            1004     998      -6
static.zero_timespec                                   8       -      -8
sigprocmask_set                                       14       -     -14
sigwaitinfo                                           23       -     -23
record_signal                                         23       -     -23
__GI_sigwaitinfo                                      23       -     -23
sigtimedwait                                          25       -     -25
builtin_trap                                         417     392     -25
__GI_sigtimedwait                                     25       -     -25
hush_main                                           1003     965     -38
check_and_run_traps                                  263     217     -46
__rt_sigtimedwait                                     52       -     -52
reset_traps_to_defaults                              213     126     -87
init_sigmasks                                        198       -    -198
builtin_read                                         536     197    -339
------------------------------------------------------------------------------
(add/remove: 5/10 grow/shrink: 2/7 up/down: 371/-934)        Total: -563 bytes
   text	   data	    bss	    dec	    hex	filename
 903075	    936	  17736	 921747	  e1093	busybox_old
 902547	    936	  17736	 921219	  e0e83	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
1 file changed