+struct timeval now;
+
+static fd_set readfds;
+static fd_set writefds;
+static volatile bool running;
+
+static int io_compare(const io_t *a, const io_t *b) {
+ return a->fd - b->fd;
+}
+
+static int timeout_compare(const timeout_t *a, const timeout_t *b) {
+ struct timeval diff;
+ timersub(&a->tv, &b->tv, &diff);
+ return diff.tv_sec ?: diff.tv_usec ?: a < b ? -1 : a > b ? 1 : 0;
+}
+
+static int signal_compare(const signal_t *a, const signal_t *b) {
+ return a->signum - b->signum;
+}
+
+static splay_tree_t io_tree = {.compare = (splay_compare_t)io_compare};
+static splay_tree_t timeout_tree = {.compare = (splay_compare_t)timeout_compare};
+static splay_tree_t signal_tree = {.compare = (splay_compare_t)signal_compare};
+
+void io_add(io_t *io, io_cb_t cb, void *data, int fd, int flags) {
+ if(io->cb)
+ return;
+
+ io->fd = fd;
+ io->cb = cb;
+ io->data = data;
+ io->node.data = io;
+
+ io_set(io, flags);
+
+ splay_insert_node(&io_tree, &io->node);
+}
+
+void io_set(io_t *io, int flags) {
+ io->flags = flags;
+
+ if(flags & IO_READ)
+ FD_SET(io->fd, &readfds);
+ else
+ FD_CLR(io->fd, &readfds);
+
+ if(flags & IO_WRITE)
+ FD_SET(io->fd, &writefds);
+ else
+ FD_CLR(io->fd, &writefds);
+}
+
+void io_del(io_t *io) {
+ if(!io->cb)
+ return;
+
+ io_set(io, 0);
+
+ splay_unlink_node(&io_tree, &io->node);
+ io->cb = NULL;
+}
+
+void timeout_add(timeout_t *timeout, timeout_cb_t cb, void *data, struct timeval *tv) {
+ if(timeout->cb)
+ return;
+
+ timeout->cb = cb;
+ timeout->data = data;
+ timeout->node.data = timeout;
+
+ timeout_set(timeout, tv);
+}
+
+void timeout_set(timeout_t *timeout, struct timeval *tv) {
+ if(timeout->tv.tv_sec)
+ splay_unlink_node(&timeout_tree, &timeout->node);
+
+ if(!now.tv_sec)
+ gettimeofday(&now, NULL);
+
+ timeradd(&now, tv, &timeout->tv);
+
+ splay_insert_node(&timeout_tree, &timeout->node);
+}
+
+void timeout_del(timeout_t *timeout) {
+ if(!timeout->cb)
+ return;
+
+ splay_unlink_node(&timeout_tree, &timeout->node);
+ timeout->cb = NULL;
+}
+
+#ifndef HAVE_MINGW
+static io_t signalio;
+static int pipefd[2] = {-1, -1};
+
+static void signal_handler(int signum) {
+ unsigned char num = signum;
+ write(pipefd[1], &num, 1);
+}
+
+static void signalio_handler(void *data, int flags) {
+ unsigned char signum;
+ if(read(pipefd[0], &signum, 1) != 1)
+ return;
+
+ signal_t *sig = splay_search(&signal_tree, &((signal_t){.signum = signum}));
+ if(sig)
+ sig->cb(sig->data);
+}
+
+static void pipe_init(void) {
+ if(!pipe(pipefd))
+ io_add(&signalio, signalio_handler, NULL, pipefd[0], IO_READ);
+}
+
+void signal_add(signal_t *sig, signal_cb_t cb, void *data, int signum) {
+ if(sig->cb)
+ return;
+
+ sig->cb = cb;
+ sig->data = data;
+ sig->signum = signum;
+ sig->node.data = sig;
+
+ if(pipefd[0] == -1)
+ pipe_init();
+
+ signal(sig->signum, signal_handler);
+
+ splay_insert_node(&signal_tree, &sig->node);
+}
+
+void signal_del(signal_t *sig) {
+ if(!sig->cb)
+ return;
+
+ signal(sig->signum, SIG_DFL);
+
+ splay_unlink_node(&signal_tree, &sig->node);
+ sig->cb = NULL;
+}
+#endif
+
+bool event_loop(void) {
+ running = true;
+
+ fd_set readable;
+ fd_set writable;
+
+ while(running) {
+ gettimeofday(&now, NULL);
+ struct timeval diff, *tv = NULL;
+
+ while(timeout_tree.head) {
+ timeout_t *timeout = timeout_tree.head->data;
+ timersub(&timeout->tv, &now, &diff);
+
+ if(diff.tv_sec < 0) {
+ timeout->cb(timeout->data);
+ if(timercmp(&timeout->tv, &now, <))
+ timeout_del(timeout);
+ } else {
+ tv = &diff;
+ break;
+ }
+ }
+
+ memcpy(&readable, &readfds, sizeof readable);
+ memcpy(&writable, &writefds, sizeof writable);
+
+ int fds = 0;
+
+ if(io_tree.tail) {
+ io_t *last = io_tree.tail->data;
+ fds = last->fd + 1;
+ }
+
+#ifdef HAVE_MINGW
+ LeaveCriticalSection(&mutex);
+#endif
+ int n = select(fds, &readable, &writable, NULL, tv);
+#ifdef HAVE_MINGW
+ EnterCriticalSection(&mutex);
+#endif
+
+ if(n < 0) {
+ if(sockwouldblock(errno))
+ continue;
+ else
+ return false;
+ }
+
+ if(!n)
+ continue;
+
+ for splay_each(io_t, io, &io_tree) {
+ if(FD_ISSET(io->fd, &writable))
+ io->cb(io->data, IO_WRITE);
+ else if(FD_ISSET(io->fd, &readable))
+ io->cb(io->data, IO_READ);
+ }
+ }
+
+ return true;
+}