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| author | Andrew Tridgell <tridge@samba.org> | 2007-01-21 23:37:32 +0000 |
|---|---|---|
| committer | Gerald (Jerry) Carter <jerry@samba.org> | 2007-10-10 14:43:56 -0500 |
| commit | fa5e920a7b4a2eba450189af35e0b5eeab80cdbc (patch) | |
| tree | 4203765d0b953d7a65948e6545e3ae9f5e2cd2c4 /source4/lib | |
| parent | 0c846b1b2db4054914a7275f9bff6155b68720b6 (diff) | |
| download | samba-fa5e920a7b4a2eba450189af35e0b5eeab80cdbc.tar.gz samba-fa5e920a7b4a2eba450189af35e0b5eeab80cdbc.tar.bz2 samba-fa5e920a7b4a2eba450189af35e0b5eeab80cdbc.zip | |
r20941: avoid races in the block/unblock code
(This used to be commit 83353ec0cd05464abb581f51d8c26ade7f0876fe)
Diffstat (limited to 'source4/lib')
| -rw-r--r-- | source4/lib/events/events_signal.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/source4/lib/events/events_signal.c b/source4/lib/events/events_signal.c index 28702cecc9..21542d863b 100644 --- a/source4/lib/events/events_signal.c +++ b/source4/lib/events/events_signal.c @@ -54,6 +54,7 @@ static struct { #ifdef SA_SIGINFO /* with SA_SIGINFO we get quite a lot of info per signal */ siginfo_t *sig_info[NUM_SIGNALS]; + struct sigcounter sig_blocked[NUM_SIGNALS]; #endif } sig_state; @@ -99,6 +100,7 @@ static void signal_handler_info(int signum, siginfo_t *info, void *uctx) sigemptyset(&set); sigaddset(&set, signum); sigprocmask(SIG_BLOCK, &set, NULL); + SIG_INCREMENT(sig_state.sig_blocked[signum]); } } #endif @@ -226,7 +228,8 @@ int common_event_check_signal(struct event_context *ev) for (i=0;i<NUM_SIGNALS+1;i++) { struct signal_event *se, *next; - uint32_t count = sig_count(sig_state.signal_count[i]); + struct sigcounter counter = sig_state.signal_count[i]; + uint32_t count = sig_count(counter); if (count == 0) { continue; @@ -237,16 +240,21 @@ int common_event_check_signal(struct event_context *ev) if (se->sa_flags & SA_SIGINFO) { int j; for (j=0;j<count;j++) { + /* note the use of the sig_info array as a + ring buffer */ + int ofs = (counter.count + j) % SA_INFO_QUEUE_COUNT; se->handler(ev, se, i, 1, - (void*)&sig_state.sig_info[i][j], + (void*)&sig_state.sig_info[i][ofs], se->private_data); } - if (count == SA_INFO_QUEUE_COUNT) { + if (SIG_PENDING(sig_state.sig_blocked[i])) { /* we'd filled the queue, unblock the signal now */ sigset_t set; sigemptyset(&set); sigaddset(&set, i); + SIG_SEEN(sig_state.sig_blocked[i], + sig_count(sig_state.sig_blocked[i])); sigprocmask(SIG_UNBLOCK, &set, NULL); } if (se->sa_flags & SA_RESETHAND) { |