Commit Graph

16 Commits

Author SHA1 Message Date
Stephen Heumann
656769d136 Work around GNO libc's buggy sigprocmask implementation by defining our own version of it. This should fix issues where hush could hang in wait() calls.
The sigprocmask implementation in GNO 2.0.6 libc has bugs that cause it to never actually unblock signals that have been blocked. This was causing many signals to remain blocked when they shouldn't be, particularly after running signal handlers.

This problem combined with a kernel issue (wait() calls won't recognize that a child has finished if SIGCHLD is blocked) to cause hangs in certain conditions.

This patch works around these issues by defining our own non-buggy version of sigprocmask in place of libc's.
2015-01-15 18:02:33 -06:00
Stephen Heumann
334678c6e9 Change various uses of signal masks to use 32-bit values (previously half the signals were essentially cut off). 2014-11-25 17:43:14 -06:00
Stephen Heumann
c37475dcbc Change vfork_and_run implementation to inspect the kernel's process tables to determine whether the child has really exec'd or exited.
This should avoid strange behavior due to races when the parent has resumed but the child is still running the exec* code in libc, which mainly manifests itself when running at low speed.

We also change to signaling the child's completion with SIGALRM, and setting an extra alarm in the parent in case the child doesn't actually do it.
2014-11-10 16:08:24 -06:00
Stephen Heumann
cbdfea4c97 Revise signal handling to work with GNO.
This involved using signal() rather than sigaction(), which GNO doesn't have. signal() doesn't have the signal-blocking feature of sigaction(), but I've tried to emulate it.
2014-11-04 10:45:28 -06:00
Denys Vlasenko
c4f2d997a4 libbb: correctness/size tweaks in signal-related helpers
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2012-09-27 13:20:34 +02:00
Denys Vlasenko
0ef64bdb40 *: make GNU licensing statement forms more regular
This change retains "or later" state! No licensing _changes_ here,
only form is adjusted (article, space between "GPL" and "v2" and so on).

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2010-08-16 20:14:46 +02:00
Denis Vlasenko
cab28aa7de init: preparatory patch, no code changes 2009-01-31 01:02:07 +00:00
Denis Vlasenko
08ea11ab07 runsvd: shrink by Vladimir
*: use unified trivial signal handler

function                                             old     new   delta
record_signo                                           -      10     +10
process_stdin                                        433     443     +10
bbunpack                                             383     391      +8
wc_main                                              598     605      +7
conescape                                            293     296      +3
nmeter_main                                          670     672      +2
fallbackSort                                        1717    1719      +2
bb_got_signal                                          -       1      +1
microcom_main                                        713     712      -1
signalled                                              2       -      -2
pack_gzip                                           1661    1659      -2
evalvar                                             1376    1374      -2
compare_keys                                         737     735      -2
parse_command                                       1460    1456      -4
expand                                              1748    1744      -4
s_term                                                37      29      -8
s_hangup                                               8       -      -8
fgotsig                                               10       -     -10
find_pair                                            187     169     -18
signal_handler                                       190     170     -20
runsvdir_main                                       1701    1583    -118
------------------------------------------------------------------------------
(add/remove: 2/3 grow/shrink: 6/10 up/down: 43/-199)         Total: -156 bytes
2008-09-11 19:51:11 +00:00
Denis Vlasenko
defc1ea340 *: introduce and use FAST_FUNC: regparm on i386, otherwise no-on
text    data     bss     dec     hex filename
 808035     611    6868  815514   c719a busybox_old
 804472     611    6868  811951   c63af busybox_unstripped
2008-06-27 02:52:20 +00:00
Bernhard Reutner-Fischer
636a1f85e8 - use EXIT_{SUCCESS,FAILURE}. No object-code changes 2008-05-19 09:29:47 +00:00
Denis Vlasenko
3f165fa5b3 libbb: introduce and use sigprocmask_allsigs and sigaction_set.
libbb: rename sig_pause to wait_for_any_sig.
2008-03-17 08:29:08 +00:00
Denis Vlasenko
8e2cfec1cd libbb: introduse and use signal_[no_]SA_RESTART_empty_mask and sigaction_set
signal_SA_RESTART_empty_mask                           -      65     +65
signal_no_SA_RESTART_empty_mask                        -      54     +54
dd_main                                             1325    1369     +44
sigaction_set                                          -      19     +19
dname_enc                                            373     377      +4
UNSPEC_print                                          64      66      +2
setsignal                                            296     294      -2
bb_signals_recursive                                  95      92      -3
bb_askpass                                           367     361      -6
inetd_main                                          1810    1797     -13
rx_main                                              912     883     -29
sigdelset                                             32       -     -32
__sigdelset                                           32       -     -32
__GI_sigdelset                                        32       -     -32
sighup_handler                                        84      37     -47
arping_main                                         1844    1797     -47
fsck_main                                           1869    1807     -62
run_list                                            1917    1844     -73
vlock_main                                           492     409     -83
progressmeter                                        883     798     -85
handle_incoming_and_exit                            2737    2651     -86
------------------------------------------------------------------------------
(add/remove: 3/3 grow/shrink: 3/12 up/down: 188/-632)        Total: -444 bytes
2008-03-12 23:19:35 +00:00
Denis Vlasenko
4cf1d08fc2 nc: remove a bit of bloat
inetd: more NOMMU fixes
rx: shrink
devfsd: minor shrink
vlock: shrink
tcpudp: narrow down window where we have no wildcard socket

parse_one_line                                      1015    1102     +87
init_ring                                              -      53     +53
xzalloc_lsa                                            -      48     +48
read_byte                                             51      50      -1
rearm_alarm                                           28      25      -3
nc_main                                             1028    1000     -28
initring                                              53       -     -53
vlock_main                                           583     496     -87
reread_config_file                                  1089     991     -98
rx_main                                             1046     912    -134
------------------------------------------------------------------------------
(add/remove: 2/1 grow/shrink: 1/6 up/down: 188/-404)         Total: -216 bytes
   text    data     bss     dec     hex filename
 800120     661    7428  808209   c5511 busybox_old
 799796     661    7428  807885   c53cd busybox_unstripped
2008-03-12 23:13:50 +00:00
Denis Vlasenko
d18f52bd18 actually add bb_qsort.c
*: s/Denis/Denys/
2008-03-02 12:53:15 +00:00
Denis Vlasenko
400d8bb45e less,klogd,syslogd,nc,tcpudp: exit on signal by killing itself, not exit(1)
*: minor shrink
2008-02-24 13:36:01 +00:00
Denis Vlasenko
25591c322c 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
2008-02-16 22:58:56 +00:00