Class: Event::Backend::EPoll

Inherits:

Object

• Object
• Event::Backend::EPoll

Defined in:

ext/event/backend/epoll.c

Instance Method Summary

• #initialize(loop) ⇒ Object constructor
• #io_wait(fiber, io, events) ⇒ Object
• #select(duration) ⇒ Object

Constructor Details

#initialize(loop) ⇒ Object

# File 'ext/event/backend/epoll.c', line 81

VALUE Event_Backend_EPoll_initialize(VALUE self, VALUE loop) {
	struct Event_Backend_EPoll *data = NULL;
	TypedData_Get_Struct(self, struct Event_Backend_EPoll, &Event_Backend_EPoll_Type, data);
	
	data->loop = loop;
	int result = epoll_create1(EPOLL_CLOEXEC);
	
	if (result == -1) {
		rb_sys_fail("epoll_create");
	} else {
		data->descriptor = result;
		
		rb_update_max_fd(data->descriptor);
	}
	
	return self;
}

Instance Method Details

#io_wait(fiber, io, events) ⇒ Object

# File 'ext/event/backend/epoll.c', line 154

VALUE Event_Backend_EPoll_io_wait(VALUE self, VALUE fiber, VALUE io, VALUE events) {
	struct Event_Backend_EPoll *data = NULL;
	TypedData_Get_Struct(self, struct Event_Backend_EPoll, &Event_Backend_EPoll_Type, data);
	
	struct epoll_event event = {0};
	
	int descriptor = NUM2INT(rb_funcall(io, id_fileno, 0));
	int duplicate = -1;
	
	event.events = epoll_flags_from_events(NUM2INT(events));
	event.data.ptr = (void*)fiber;
	
	// fprintf(stderr, "<- fiber=%p descriptor=%d\n", (void*)fiber, descriptor);
	
	// A better approach is to batch all changes:
	int result = epoll_ctl(data->descriptor, EPOLL_CTL_ADD, descriptor, &event);
	
	if (result == -1 && errno == EEXIST) {
		// The file descriptor was already inserted into epoll.
		duplicate = descriptor = dup(descriptor);
		
		rb_update_max_fd(duplicate);
		
		if (descriptor == -1)
			rb_sys_fail("dup");
		
		result = epoll_ctl(data->descriptor, EPOLL_CTL_ADD, descriptor, &event);
	}
	
	if (result == -1) {
		rb_sys_fail("epoll_ctl");
	}
	
	struct io_wait_arguments io_wait_arguments = {
		.data = data,
		.descriptor = descriptor,
		.duplicate = duplicate
	};
	
	return rb_ensure(io_wait_transfer, (VALUE)&io_wait_arguments, io_wait_ensure, (VALUE)&io_wait_arguments);
}

#select(duration) ⇒ Object

# File 'ext/event/backend/epoll.c', line 215

VALUE Event_Backend_EPoll_select(VALUE self, VALUE duration) {
	struct Event_Backend_EPoll *data = NULL;
	TypedData_Get_Struct(self, struct Event_Backend_EPoll, &Event_Backend_EPoll_Type, data);
	
	struct epoll_event events[EPOLL_MAX_EVENTS];
	
	int count = epoll_wait(data->descriptor, events, EPOLL_MAX_EVENTS, make_timeout(duration));
	
	if (count == -1) {
		rb_sys_fail("epoll_wait");
	}
	
	for (int i = 0; i < count; i += 1) {
		VALUE fiber = (VALUE)events[i].data.ptr;
		VALUE result = INT2NUM(events[i].events);
		
		// fprintf(stderr, "-> fiber=%p descriptor=%d\n", (void*)fiber, events[i].data.fd);
		
		rb_funcall(fiber, id_transfer, 1, result);
	}
	
	return INT2NUM(count);
}