sig is checked for < 0 or > MAX_SIGNAL, but the signal array is
MAX_SIGNAL in size. At the moment, MAX_SIGNAL is 256. If a system supports
more than MAX_SIGNAL signals, then sending signal MAX_SIGNAL to the process
will corrupt one integer in its memory and might also crash the process.
This bug is also present in 1.4 and 1.3, and the fix must be backported.
Reported-by: Dinko Korunic <dkorunic@reflected.net>
SIGPROF is blocked then restored to default settings, which sometimes
makes profiling harder. Let's not block it by default nor restore it,
it doesn't serve any purpose anyway.
Until now, signals configured with no handler were still enabled and
ignored upon signal reception. Until now it was not an issue but with
SSL causing many EPIPE all the time, it becomes obvious that signal
processing comes with a cost. So set the handler to SIG_IGN when the
function is NULL.
Signal zero is never delivered by the system. However having a signal to
which functions and tasks can subscribe to be notified of a stopping event
is useful. So this patch does two things :
1) allow signal zero to be delivered from any function of signal handler
2) make soft_stop() deliver this signal so that tasks can be notified of
a stopping condition.
The two new functions below make it possible to register any number
of functions or tasks to a system signal. They will be called in the
registration order when the signal is received.
struct sig_handler *signal_register_fct(int sig, void (*fct)(struct sig_handler *), int arg);
struct sig_handler *signal_register_task(int sig, struct task *task, int reason);
AIX wants string.h in signal.c (and is right to do so) :
gcc -Iinclude -Wall -O2 -g -DTPROXY -DENABLE_POLL -DCONFIG_HAPROXY_VERSION=\"1.3.18\" -DCONFIG_HAPROXY_DATE=\"2009/05/10\" -c -o src/signal.o src/signal.c
src/signal.c: In function 'signal_init':
src/signal.c:32: warning: implicit declaration of function 'memset'
src/signal.c:32: warning: incompatible implicit declaration of built-in function 'memset'
These functions will be used to deliver asynchronous signals in order
to make the signal handling functions more robust. The goal is to keep
the same interface to signal handlers.
