#include <sys/types.h>
#include <sys/socket.h>
#include <limits.h>
+#include <errno.h>
-static size_t num_fds = 0, max_fds = 0, num_next = 0, num_finished = 0, num_waiting = 0;
+static size_t num_fds = 0, max_fds = 0, num_closing = 0, num_waiting = 0;
+static bool some_always = false;
static struct pollfd *pollfds = NULL;
static struct fd **fds = NULL;
static struct timers timeouts;
+#ifdef DEBUG
+static unsigned int io_loop_level;
+static struct io_conn *free_later;
+static void io_loop_enter(void)
+{
+ io_loop_level++;
+}
+static void io_loop_exit(void)
+{
+ io_loop_level--;
+ if (io_loop_level == 0) {
+ /* Delayed free. */
+ while (free_later) {
+ struct io_conn *c = free_later;
+ free_later = c->finish_arg;
+ io_alloc.free(c);
+ }
+ }
+}
+static void free_conn(struct io_conn *conn)
+{
+ /* Only free on final exit: chain via finish. */
+ if (io_loop_level > 1) {
+ struct io_conn *c;
+ for (c = free_later; c; c = c->finish_arg)
+ assert(c != conn);
+ conn->finish_arg = free_later;
+ free_later = conn;
+ } else
+ io_alloc.free(conn);
+}
+#else
+static void io_loop_enter(void)
+{
+}
+static void io_loop_exit(void)
+{
+}
+static void free_conn(struct io_conn *conn)
+{
+ io_alloc.free(conn);
+}
+#endif
static bool add_fd(struct fd *fd, short events)
{
struct fd **newfds;
size_t num = max_fds ? max_fds * 2 : 8;
- newpollfds = realloc(pollfds, sizeof(*newpollfds) * num);
+ newpollfds = io_alloc.realloc(pollfds, sizeof(*newpollfds)*num);
if (!newpollfds)
return false;
pollfds = newpollfds;
- newfds = realloc(fds, sizeof(*newfds) * num);
+ newfds = io_alloc.realloc(fds, sizeof(*newfds) * num);
if (!newfds)
return false;
fds = newfds;
max_fds = num;
}
- pollfds[num_fds].fd = fd->fd;
pollfds[num_fds].events = events;
+ /* In case it's idle. */
+ if (!events)
+ pollfds[num_fds].fd = -fd->fd;
+ 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;
num_fds++;
+ if (events)
+ num_waiting++;
+
return true;
}
assert(n != -1);
assert(n < num_fds);
+ if (pollfds[n].events)
+ num_waiting--;
if (n != num_fds - 1) {
/* Move last one over us. */
pollfds[n] = pollfds[num_fds-1];
fds[n] = fds[num_fds-1];
assert(fds[n]->backend_info == num_fds-1);
fds[n]->backend_info = n;
+ /* If that happens to be a duplex, move that too. */
+ if (!fds[n]->listener) {
+ struct io_conn *c = (void *)fds[n];
+ if (c->duplex) {
+ assert(c->duplex->fd.backend_info == num_fds-1);
+ c->duplex->fd.backend_info = n;
+ }
+ }
} else if (num_fds == 1) {
/* Free everything when no more fds. */
- free(pollfds);
- free(fds);
+ io_alloc.free(pollfds);
+ io_alloc.free(fds);
pollfds = NULL;
fds = NULL;
max_fds = 0;
{
if (!add_fd(&l->fd, POLLIN))
return false;
- num_waiting++;
return true;
}
+void backend_plan_changed(struct io_conn *conn)
+{
+ struct pollfd *pfd;
+
+ /* This can happen with debugging and delayed free... */
+ if (conn->fd.backend_info == -1)
+ return;
+
+ pfd = &pollfds[conn->fd.backend_info];
+
+ if (pfd->events)
+ num_waiting--;
+
+ pfd->events = conn->plan.pollflag & (POLLIN|POLLOUT);
+ if (conn->duplex) {
+ int mask = conn->duplex->plan.pollflag & (POLLIN|POLLOUT);
+ /* You can't *both* read/write. */
+ assert(!mask || pfd->events != mask);
+ pfd->events |= mask;
+ }
+ if (pfd->events) {
+ num_waiting++;
+ pfd->fd = conn->fd.fd;
+ } else
+ pfd->fd = -conn->fd.fd;
+
+ if (!conn->plan.next)
+ num_closing++;
+
+ if (conn->plan.pollflag == POLLALWAYS)
+ some_always = true;
+}
+
bool add_conn(struct io_conn *c)
{
- if (!add_fd(&c->fd, 0))
+ if (!add_fd(&c->fd, c->plan.pollflag & (POLLIN|POLLOUT)))
return false;
- num_next++;
+ /* Immediate close is allowed. */
+ if (!c->plan.next)
+ num_closing++;
+ if (c->plan.pollflag == POLLALWAYS)
+ some_always = true;
return true;
}
bool add_duplex(struct io_conn *c)
{
c->fd.backend_info = c->duplex->fd.backend_info;
- num_next++;
+ backend_plan_changed(c);
return true;
}
-static void del_conn(struct io_conn *conn)
+void backend_del_conn(struct io_conn *conn)
{
- if (conn->finish)
+ if (conn->finish) {
+ /* Saved by io_close */
+ errno = conn->plan.u1.s;
conn->finish(conn, conn->finish_arg);
+ }
if (timeout_active(conn))
backend_del_timeout(conn);
- free(conn->timeout);
+ io_alloc.free(conn->timeout);
if (conn->duplex) {
/* In case fds[] pointed to the other one. */
+ assert(conn->duplex->fd.backend_info == conn->fd.backend_info);
fds[conn->fd.backend_info] = &conn->duplex->fd;
conn->duplex->duplex = NULL;
+ conn->fd.backend_info = -1;
} else
del_fd(&conn->fd);
- if (conn->state == FINISHED)
- num_finished--;
- else if (conn->state == NEXT)
- num_next--;
+ num_closing--;
+ free_conn(conn);
}
void del_listener(struct io_listener *l)
del_fd(&l->fd);
}
-void backend_set_state(struct io_conn *conn, struct io_plan *plan)
+static void set_plan(struct io_conn *conn, struct io_plan plan)
{
- enum io_state state = from_ioplan(plan);
- struct pollfd *pfd = &pollfds[conn->fd.backend_info];
-
- if (pfd->events)
- num_waiting--;
-
- pfd->events = conn->pollflag;
- if (conn->duplex) {
- int mask = conn->duplex->pollflag;
- /* You can't *both* read/write. */
- assert(!mask || pfd->events != mask);
- pfd->events |= mask;
- }
- if (pfd->events)
- num_waiting++;
-
- if (state == NEXT)
- num_next++;
- else if (state == FINISHED)
- num_finished++;
-
- conn->state = state;
+ conn->plan = plan;
+ backend_plan_changed(conn);
}
static void accept_conn(struct io_listener *l)
{
- struct io_conn *c;
int fd = accept(l->fd.fd, NULL, NULL);
/* FIXME: What to do here? */
if (fd < 0)
return;
- c = io_new_conn(fd, l->next, l->finish, l->conn_arg);
- if (!c) {
- close(fd);
- return;
- }
+ l->init(fd, l->arg);
}
/* It's OK to miss some, as long as we make progress. */
-static void finish_and_next(bool finished_only)
+static bool finish_conns(struct io_conn **ready)
{
unsigned int i;
for (i = 0; !io_loop_return && i < num_fds; i++) {
struct io_conn *c, *duplex;
- if (!num_finished) {
- if (finished_only || num_next == 0)
- break;
- }
+ if (!num_closing)
+ break;
+
if (fds[i]->listener)
continue;
c = (void *)fds[i];
for (duplex = c->duplex; c; c = duplex, duplex = NULL) {
- if (c->state == FINISHED) {
- del_conn(c);
- free(c);
+ if (!c->plan.next) {
+ if (doing_debug_on(c) && ready) {
+ *ready = c;
+ return true;
+ }
+ backend_del_conn(c);
i--;
- } else if (!finished_only && c->state == NEXT) {
- backend_set_state(c, c->next(c, c->next_arg));
- num_next--;
}
}
}
-}
-
-static void ready(struct io_conn *c)
-{
- backend_set_state(c, do_ready(c));
+ return false;
}
void backend_add_timeout(struct io_conn *conn, struct timespec duration)
conn->timeout->conn = NULL;
}
+static void handle_always(void)
+{
+ int i;
+
+ some_always = false;
+
+ for (i = 0; i < num_fds && !io_loop_return; i++) {
+ struct io_conn *c = (void *)fds[i];
+
+ if (fds[i]->listener)
+ continue;
+
+ if (c->plan.pollflag == POLLALWAYS)
+ io_ready(c);
+
+ if (c->duplex && c->duplex->plan.pollflag == POLLALWAYS)
+ io_ready(c->duplex);
+ }
+}
+
/* This is the main loop. */
-void *io_loop(void)
+void *do_io_loop(struct io_conn **ready)
{
void *ret;
+ io_loop_enter();
+
while (!io_loop_return) {
int i, r, timeout = INT_MAX;
struct timespec now;
+ bool some_timeouts = false;
if (timeouts.base) {
struct timespec first;
struct io_conn *conn = t->conn;
/* Clear, in case timer re-adds */
t->conn = NULL;
- backend_set_state(conn, t->next(conn, t->next_arg));
+ set_current(conn);
+ set_plan(conn, t->next(conn, t->next_arg));
+ some_timeouts = true;
}
/* Now figure out how long to wait for the next one. */
}
}
- if (num_finished || num_next) {
- finish_and_next(false);
+ if (num_closing) {
+ /* If this finishes a debugging con, return now. */
+ if (finish_conns(ready))
+ return NULL;
/* Could have started/finished more. */
continue;
}
+ /* debug can recurse on io_loop; anything can change. */
+ if (doing_debug() && some_timeouts)
+ continue;
+
+ if (some_always) {
+ handle_always();
+ continue;
+ }
+
if (num_fds == 0)
break;
} else if (events & (POLLIN|POLLOUT)) {
r--;
if (c->duplex) {
- int mask = c->duplex->pollflag;
+ int mask = c->duplex->plan.pollflag;
if (events & mask) {
- ready(c->duplex);
+ if (doing_debug_on(c->duplex)
+ && ready) {
+ *ready = c->duplex;
+ return NULL;
+ }
+ io_ready(c->duplex);
events &= ~mask;
- if (!(events&(POLLIN|POLLOUT)))
+ /* debug can recurse;
+ * anything can change. */
+ if (doing_debug())
+ break;
+
+ /* If no events, or it closed
+ * the duplex, continue. */
+ if (!(events&(POLLIN|POLLOUT))
+ || !c->plan.next)
continue;
}
}
- ready(c);
- } else if (events & POLLHUP) {
+ if (doing_debug_on(c) && ready) {
+ *ready = c;
+ return NULL;
+ }
+ io_ready(c);
+ /* debug can recurse; anything can change. */
+ if (doing_debug())
+ break;
+ } else if (events & (POLLHUP|POLLNVAL|POLLERR)) {
r--;
- backend_set_state(c, io_close(c, NULL));
- if (c->duplex)
- backend_set_state(c->duplex,
- io_close(c->duplex,
- NULL));
+ set_current(c);
+ errno = EBADF;
+ set_plan(c, io_close());
+ if (c->duplex) {
+ set_current(c->duplex);
+ set_plan(c->duplex, io_close());
+ }
}
}
}
- while (num_finished)
- finish_and_next(true);
+ while (num_closing && !io_loop_return) {
+ if (finish_conns(ready))
+ return NULL;
+ }
ret = io_loop_return;
io_loop_return = NULL;
+
+ io_loop_exit();
return ret;
}
+
+void *io_loop(void)
+{
+ return do_io_loop(NULL);
+}
projects / ccan / blobdiff