int
evsig_init_(struct event_base *base)
{
/*
* Our signal handler is going to write to one end of the socket
* pair to wake up our event loop. The event loop then scans for
* signals that got delivered.
*/
if (evutil_make_internal_pipe_(base->sig.ev_signal_pair) == -1) {
#ifdef _WIN32
/* Make this nonfatal on win32, where sometimes people
have localhost firewalled. */
event_sock_warn(-1, "%s: socketpair", __func__);
#else
event_sock_err(1, -1, "%s: socketpair", __func__);
#endif
return -1;
}
if (base->sig.sh_old) {
mm_free(base->sig.sh_old);
}
base->sig.sh_old = NULL;
base->sig.sh_old_max = 0;
event_assign(&base->sig.ev_signal, base, base->sig.ev_signal_pair[0],
EV_READ | EV_PERSIST, evsig_cb, base);
base->sig.ev_signal.ev_flags |= EVLIST_INTERNAL;
event_priority_set(&base->sig.ev_signal, 0);
base->evsigsel = &evsigops;
return 0;
}
static void
sock_err_fn(void)
{
evutil_socket_t fd = socket(AF_INET, SOCK_STREAM, 0);
#ifdef _WIN32
EVUTIL_SET_SOCKET_ERROR(WSAEWOULDBLOCK);
#else
errno = EAGAIN;
#endif
event_sock_err(20, fd, "Unhappy socket");
}
/* Callback for when the signal handler write a byte to our signaling socket */
static void
evsig_cb(evutil_socket_t fd, short what, void *arg)
{
static char signals[1];
ev_ssize_t n;
(void)arg; /* Suppress "unused variable" warning. */
n = recv(fd, signals, sizeof(signals), 0);
if (n == -1)
event_sock_err(1, fd, "%s: read", __func__);
}
/* Callback for when the signal handler write a byte to our signaling socket */
static void
evsig_cb(evutil_socket_t fd, short what, void *arg)
{
static char signals[1024];
ev_ssize_t n;
int i;
int ncaught[NSIG];
struct event_base *base;
base = arg;
memset(&ncaught, 0, sizeof(ncaught));
while (1) {
#ifdef _WIN32
n = recv(fd, signals, sizeof(signals), 0);
#else
n = read(fd, signals, sizeof(signals));
#endif
if (n == -1) {
int err = evutil_socket_geterror(fd);
if (! EVUTIL_ERR_RW_RETRIABLE(err))
event_sock_err(1, fd, "%s: recv", __func__);
break;
} else if (n == 0) {
/* XXX warn? */
break;
}
for (i = 0; i < n; ++i) {
ev_uint8_t sig = signals[i];
if (sig < NSIG)
ncaught[sig]++;
}
}
EVBASE_ACQUIRE_LOCK(base, th_base_lock);
for (i = 0; i < NSIG; ++i) {
if (ncaught[i])
evmap_signal_active_(base, i, ncaught[i]);
}
EVBASE_RELEASE_LOCK(base, th_base_lock);
}
int
evsig_init(struct event_base *base)
{
/*
* Our signal handler is going to write to one end of the socket
* pair to wake up our event loop. The event loop then scans for
* signals that got delivered.
*/
if (evutil_socketpair(
AF_UNIX, SOCK_STREAM, 0, base->sig.ev_signal_pair) == -1) {
#ifdef WIN32
/* Make this nonfatal on win32, where sometimes people
have localhost firewalled. */
event_sock_warn(-1, "%s: socketpair", __func__);
#else
event_sock_err(1, -1, "%s: socketpair", __func__);
#endif
return -1;
}
evutil_make_socket_closeonexec(base->sig.ev_signal_pair[0]);
evutil_make_socket_closeonexec(base->sig.ev_signal_pair[1]);
base->sig.sh_old = NULL;
base->sig.sh_old_max = 0;
base->sig.evsig_caught = 0;
memset(&base->sig.evsigcaught, 0, sizeof(sig_atomic_t)*NSIG);
evutil_make_socket_nonblocking(base->sig.ev_signal_pair[0]);
event_assign(&base->sig.ev_signal, base, base->sig.ev_signal_pair[1],
EV_READ | EV_PERSIST, evsig_cb, &base->sig.ev_signal);
base->sig.ev_signal.ev_flags |= EVLIST_INTERNAL;
base->evsigsel = &evsigops;
base->evsigbase = &base->sig;
return 0;
}
//初始化base->sig成员
int
evsig_init(struct event_base *base)
{
/*
* Our signal handler is going to write to one end of the socket
* pair to wake up our event loop. The event loop then scans for
* signals that got delivered. //这感觉就是上一个函数的功能
*/
if (evutil_socketpair(
AF_UNIX, SOCK_STREAM, 0, base->sig.ev_signal_pair) == -1) {
#ifdef WIN32
/* Make this nonfatal on win32, where sometimes people
have localhost firewalled. */
event_sock_warn(-1, "%s: socketpair", __func__);
#else
event_sock_err(1, -1, "%s: socketpair", __func__);
#endif
return -1;
}
evutil_make_socket_closeonexec(base->sig.ev_signal_pair[0]);//两个都设置执行时关闭
evutil_make_socket_closeonexec(base->sig.ev_signal_pair[1]);
base->sig.sh_old = NULL; //？
base->sig.sh_old_max = 0;
evutil_make_socket_nonblocking(base->sig.ev_signal_pair[0]);//设置为非阻塞
evutil_make_socket_nonblocking(base->sig.ev_signal_pair[1]);
event_assign(&base->sig.ev_signal, base, base->sig.ev_signal_pair[1],//注册了上一个函数evsig_cb为回调函数
EV_READ | EV_PERSIST, evsig_cb, base);
base->sig.ev_signal.ev_flags |= EVLIST_INTERNAL;//sig为evsig_info类型，ev_signal为event类型。设置为内部，一直没搞懂是啥
event_priority_set(&base->sig.ev_signal, 0);//初始优先级为0
base->evsigsel = &evsigops;//设置信号处理的后端
return 0;
}
/* Callback for when the signal handler write a byte to our signaling socket */
static void
evsig_cb(evutil_socket_t fd, short what, void *arg)
{
static char signals[1024];//用来存放信号处理函数传过来的的信号？
ev_ssize_t n;
int i;
int ncaught[NSIG];//NSIG在哪定义？
struct event_base *base;
base = arg;
memset(&ncaught, 0, sizeof(ncaught));
while (1) {
n = recv(fd, signals, sizeof(signals), 0);
if (n == -1) {
int err = evutil_socket_geterror(fd);//windows平台这是函数，而linux平台这是宏函数
if (! EVUTIL_ERR_RW_RETRIABLE(err)) //判断是否可重读写，即检查EINTR和EAGAIN
event_sock_err(1, fd, "%s: recv", __func__);
break;
} else if (n == 0) {
/* XXX warn? */
break;
}
for (i = 0; i < n; ++i) {
ev_uint8_t sig = signals[i];
if (sig < NSIG)
ncaught[sig]++;//记录传进来的信号
}
}
EVBASE_ACQUIRE_LOCK(base, th_base_lock);//base虽然是在本函数中定义的，貌似在栈上，但是他指向的地址是从外部传过来的，所以需要加锁
for (i = 0; i < NSIG; ++i) {
if (ncaught[i])
evmap_signal_active(base, i, ncaught[i]);//激活base中等待的信号
}
EVBASE_RELEASE_LOCK(base, th_base_lock);
}
static void
test_evutil_log(void *ptr)
{
evutil_socket_t fd = -1;
char buf[128];
event_set_log_callback(logfn);
event_set_fatal_callback(fatalfn);
#define RESET() do { \
logsev = exited = exitcode = 0; \
if (logmsg) free(logmsg); \
logmsg = NULL; \
} while (0)
#define LOGEQ(sev,msg) do { \
tt_int_op(logsev,==,sev); \
tt_assert(logmsg != NULL); \
tt_str_op(logmsg,==,msg); \
} while (0)
event_errx(2, "Fatal error; too many kumquats (%d)", 5);
LOGEQ(_EVENT_LOG_ERR, "Fatal error; too many kumquats (5)");
tt_int_op(exitcode,==,2);
RESET();
event_warnx("Far too many %s (%d)", "wombats", 99);
LOGEQ(_EVENT_LOG_WARN, "Far too many wombats (99)");
tt_int_op(exited,==,0);
RESET();
event_msgx("Connecting lime to coconut");
LOGEQ(_EVENT_LOG_MSG, "Connecting lime to coconut");
tt_int_op(exited,==,0);
RESET();
event_debug(("A millisecond passed! We should log that!"));
#ifdef USE_DEBUG
LOGEQ(_EVENT_LOG_DEBUG, "A millisecond passed! We should log that!");
#else
tt_int_op(logsev,==,0);
tt_ptr_op(logmsg,==,NULL);
#endif
RESET();
/* Try with an errno. */
errno = ENOENT;
event_warn("Couldn't open %s", "/bad/file");
evutil_snprintf(buf, sizeof(buf),
"Couldn't open /bad/file: %s",strerror(ENOENT));
LOGEQ(_EVENT_LOG_WARN,buf);
tt_int_op(exited, ==, 0);
RESET();
errno = ENOENT;
event_err(5,"Couldn't open %s", "/very/bad/file");
evutil_snprintf(buf, sizeof(buf),
"Couldn't open /very/bad/file: %s",strerror(ENOENT));
LOGEQ(_EVENT_LOG_ERR,buf);
tt_int_op(exitcode, ==, 5);
RESET();
/* Try with a socket errno. */
fd = socket(AF_INET, SOCK_STREAM, 0);
#ifdef WIN32
evutil_snprintf(buf, sizeof(buf),
"Unhappy socket: %s",
evutil_socket_error_to_string(WSAEWOULDBLOCK));
EVUTIL_SET_SOCKET_ERROR(WSAEWOULDBLOCK);
#else
evutil_snprintf(buf, sizeof(buf),
"Unhappy socket: %s", strerror(EAGAIN));
errno = EAGAIN;
#endif
event_sock_warn(fd, "Unhappy socket");
LOGEQ(_EVENT_LOG_WARN, buf);
tt_int_op(exited,==,0);
RESET();
#ifdef WIN32
EVUTIL_SET_SOCKET_ERROR(WSAEWOULDBLOCK);
#else
errno = EAGAIN;
#endif
event_sock_err(200, fd, "Unhappy socket");
LOGEQ(_EVENT_LOG_ERR, buf);
tt_int_op(exitcode,==,200);
RESET();
#undef RESET
#undef LOGEQ
end:
if (logmsg)
free(logmsg);
if (fd >= 0)
EVUTIL_CLOSESOCKET(fd);
}
