#include <ccan/time/time.h>
#include <ccan/timer/timer.h>
-static size_t num_fds = 0, max_fds = 0, num_waiting = 0;
+static size_t num_fds = 0, max_fds = 0, num_waiting = 0, num_always = 0, max_always = 0, num_exclusive = 0;
static struct pollfd *pollfds = NULL;
static struct fd **fds = NULL;
-static LIST_HEAD(closing);
-static LIST_HEAD(always);
+static struct io_plan **always = NULL;
static struct timemono (*nowfn)(void) = time_mono;
static int (*pollfn)(struct pollfd *fds, nfds_t nfds, int timeout) = poll;
pollfds[num_fds].events = events;
/* In case it's idle. */
if (!events)
- pollfds[num_fds].fd = -fd->fd;
+ pollfds[num_fds].fd = -fd->fd - 1;
else
pollfds[num_fds].fd = fd->fd;
pollfds[num_fds].revents = 0; /* In case we're iterating now */
fds[num_fds] = fd;
fd->backend_info = num_fds;
+ fd->exclusive[0] = fd->exclusive[1] = false;
num_fds++;
if (events)
num_waiting++;
pollfds = tal_free(pollfds);
fds = NULL;
max_fds = 0;
+ if (num_always == 0) {
+ always = tal_free(always);
+ max_always = 0;
+ }
}
num_fds--;
fd->backend_info = -1;
+
+ if (fd->exclusive[IO_IN])
+ num_exclusive--;
+ if (fd->exclusive[IO_OUT])
+ num_exclusive--;
}
static void destroy_listener(struct io_listener *l)
return true;
}
-void remove_from_always(struct io_conn *conn)
+static int find_always(const struct io_plan *plan)
{
- list_del_init(&conn->always);
+ for (size_t i = 0; i < num_always; i++)
+ if (always[i] == plan)
+ return i;
+ return -1;
}
-void backend_new_always(struct io_conn *conn)
+static void remove_from_always(const struct io_plan *plan)
{
- /* In case it's already in always list. */
- list_del(&conn->always);
- list_add_tail(&always, &conn->always);
+ int pos;
+
+ if (plan->status != IO_ALWAYS)
+ return;
+
+ pos = find_always(plan);
+ assert(pos >= 0);
+
+ /* Move last one down if we made a hole */
+ if (pos != num_always-1)
+ always[pos] = always[num_always-1];
+ num_always--;
+
+ /* Only free if no fds left either. */
+ if (num_always == 0 && max_fds == 0) {
+ always = tal_free(always);
+ max_always = 0;
+ }
}
-void backend_new_plan(struct io_conn *conn)
+bool backend_new_always(struct io_plan *plan)
{
- struct pollfd *pfd = &pollfds[conn->fd.backend_info];
+ assert(find_always(plan) == -1);
- if (pfd->events)
- num_waiting--;
+ if (!max_always) {
+ assert(num_always == 0);
+ always = tal_arr(NULL, struct io_plan *, 8);
+ if (!always)
+ return false;
+ max_always = 8;
+ }
+
+ if (num_always + 1 > max_always) {
+ size_t num = max_always * 2;
+
+ if (!tal_resize(&always, num))
+ return false;
+ max_always = num;
+ }
+
+ always[num_always++] = plan;
+ return true;
+}
+
+static void setup_pfd(struct io_conn *conn, struct pollfd *pfd)
+{
+ assert(pfd == &pollfds[conn->fd.backend_info]);
pfd->events = 0;
if (conn->plan[IO_IN].status == IO_POLLING_NOTSTARTED
pfd->events |= POLLOUT;
if (pfd->events) {
- num_waiting++;
pfd->fd = conn->fd.fd;
} else {
- pfd->fd = -conn->fd.fd;
+ pfd->fd = -conn->fd.fd - 1;
}
}
+void backend_new_plan(struct io_conn *conn)
+{
+ struct pollfd *pfd = &pollfds[conn->fd.backend_info];
+
+ if (pfd->events)
+ num_waiting--;
+
+ setup_pfd(conn, pfd);
+
+ if (pfd->events)
+ num_waiting++;
+}
+
void backend_wake(const void *wait)
{
unsigned int i;
if (close_fd)
close(conn->fd.fd);
del_fd(&conn->fd);
- /* In case it's on always list, remove it. */
- list_del_init(&conn->always);
+
+ remove_from_always(&conn->plan[IO_IN]);
+ remove_from_always(&conn->plan[IO_OUT]);
/* errno saved/restored by tal_free itself. */
if (conn->finish) {
io_new_conn(l->ctx, fd, l->init, l->arg);
}
-static bool handle_always(void)
+/* Return pointer to exclusive flag for this plan. */
+static bool *exclusive(struct io_plan *plan)
{
- bool ret = false;
struct io_conn *conn;
- while ((conn = list_pop(&always, struct io_conn, always)) != NULL) {
- assert(conn->plan[IO_IN].status == IO_ALWAYS
- || conn->plan[IO_OUT].status == IO_ALWAYS);
+ conn = container_of(plan, struct io_conn, plan[plan->dir]);
+ return &conn->fd.exclusive[plan->dir];
+}
- /* Re-initialize, for next time. */
- list_node_init(&conn->always);
- io_do_always(conn);
- ret = true;
+/* For simplicity, we do one always at a time */
+static bool handle_always(void)
+{
+ /* Backwards is simple easier to remove entries */
+ for (int i = num_always - 1; i >= 0; i--) {
+ struct io_plan *plan = always[i];
+
+ if (num_exclusive && !*exclusive(plan))
+ continue;
+ /* Remove first: it might re-add */
+ if (i != num_always-1)
+ always[i] = always[num_always-1];
+ num_always--;
+ io_do_always(plan);
+ return true;
+ }
+
+ return false;
+}
+
+bool backend_set_exclusive(struct io_plan *plan, bool excl)
+{
+ bool *excl_ptr = exclusive(plan);
+
+ if (excl != *excl_ptr) {
+ *excl_ptr = excl;
+ if (!excl)
+ num_exclusive--;
+ else
+ num_exclusive++;
+ }
+
+ return num_exclusive != 0;
+}
+
+/* FIXME: We could do this once at set_exclusive time, and catch everywhere
+ * else that we manipulate events. */
+static void exclude_pollfds(void)
+{
+ if (num_exclusive == 0)
+ return;
+
+ for (size_t i = 0; i < num_fds; i++) {
+ struct pollfd *pfd = &pollfds[fds[i]->backend_info];
+
+ if (!fds[i]->exclusive[IO_IN])
+ pfd->events &= ~POLLIN;
+ if (!fds[i]->exclusive[IO_OUT])
+ pfd->events &= ~POLLOUT;
+
+ /* If we're not listening, we don't want error events
+ * either. */
+ if (!pfd->events)
+ pfd->fd = -fds[i]->fd - 1;
+ }
+}
+
+static void restore_pollfds(void)
+{
+ if (num_exclusive == 0)
+ return;
+
+ for (size_t i = 0; i < num_fds; i++) {
+ struct pollfd *pfd = &pollfds[fds[i]->backend_info];
+
+ if (fds[i]->listener) {
+ pfd->events = POLLIN;
+ pfd->fd = fds[i]->fd;
+ } else {
+ struct io_conn *conn = (void *)fds[i];
+ setup_pfd(conn, pfd);
+ }
}
- return ret;
}
/* This is the main loop. */
}
}
+ /* We do this temporarily, assuming exclusive is unusual */
+ exclude_pollfds();
r = pollfn(pollfds, num_fds, ms_timeout);
- if (r < 0)
+ restore_pollfds();
+
+ if (r < 0) {
+ /* Signals shouldn't break us, unless they set
+ * io_loop_return. */
+ if (errno == EINTR)
+ continue;
break;
+ }
for (i = 0; i < num_fds && !io_loop_return; i++) {
struct io_conn *c = (void *)fds[i];
int events = pollfds[i].revents;
+ /* Clear so we don't get confused if exclusive next time */
+ pollfds[i].revents = 0;
+
if (r == 0)
break;
projects / ccan / blobdiff