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Allow WebSockets to micromanage shutdowns

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They have their reasons, mostly event-related.
This commit is contained in:
Přemysl Eric Janouch
2018-10-17 23:26:11 +02:00
parent a3ec0942f8
commit cf56921c4e
1 changed files with 35 additions and 24 deletions
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59
demo-json-rpc-server.c
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@@ -1854,10 +1854,11 @@ struct client
int socket_fd; ///< The network socket
bool received_eof; ///< Whether EOF has been received yet
bool closing; ///< Whether we're just flushing buffers
bool half_closed; ///< Transport half-closed while closing
bool flushing; ///< No more data to write, send FIN
bool closing; ///< No more data to read or write
bool half_closed; ///< Conn. half-closed while flushing
struct write_queue write_queue; ///< Write queue
ev_timer flush_timeout_watcher; ///< Write queue flush timer
ev_timer close_timeout_watcher; ///< Write queue flush timer
ev_io read_watcher; ///< The socket can be read from
ev_io write_watcher; ///< The socket can be written to
@@ -1881,17 +1882,6 @@ struct client_vtable
void (*finalize) (struct client *client);
};
static void
client_write (struct client *self, const void *data, size_t len)
{
struct write_req *req = xcalloc (1, sizeof *req);
req->data.iov_base = memcpy (xmalloc (len), data, len);
req->data.iov_len = len;
write_queue_add (&self->write_queue, req);
ev_io_start (EV_DEFAULT_ &self->write_watcher);
}
static void
client_destroy (struct client *self)
{
@@ -1907,12 +1897,36 @@ client_destroy (struct client *self)
ev_io_stop (EV_DEFAULT_ &self->write_watcher);
xclose (self->socket_fd);
write_queue_free (&self->write_queue);
ev_timer_stop (EV_DEFAULT_ &self->flush_timeout_watcher);
ev_timer_stop (EV_DEFAULT_ &self->close_timeout_watcher);
free (self);
try_finish_quit (ctx);
}
static void
client_write (struct client *self, const void *data, size_t len)
{
if (!soft_assert (!self->flushing))
return;
struct write_req *req = xcalloc (1, sizeof *req);
req->data.iov_base = memcpy (xmalloc (len), data, len);
req->data.iov_len = len;
write_queue_add (&self->write_queue, req);
ev_io_start (EV_DEFAULT_ &self->write_watcher);
}
/// Half-close the connection from our side once the write_queue is flushed.
/// It is the caller's responsibility to destroy the connection upon EOF.
// XXX: or we might change on_client_readable to do it anyway, seems safe
static void
client_shutdown (struct client *self)
{
self->flushing = true;
ev_feed_event (EV_DEFAULT_ &self->write_watcher, EV_WRITE);
}
/// Try to cleanly close the connection, waiting for the remote client to close
/// its own side of the connection as a sign that it has processed all the data
/// it wanted to. The client implementation will not receive any further data.
@@ -1924,8 +1938,8 @@ client_close (struct client *self)
return;
self->closing = true;
ev_timer_start (EV_DEFAULT_ &self->flush_timeout_watcher);
ev_feed_event (EV_DEFAULT_ &self->write_watcher, EV_WRITE);
ev_timer_start (EV_DEFAULT_ &self->close_timeout_watcher);
client_shutdown (self);
// We assume the remote client doesn't want our data if it half-closes
if (self->received_eof)
@@ -1996,7 +2010,7 @@ on_client_writable (EV_P_ ev_io *watcher, int revents)
return;
ev_io_stop (EV_A_ watcher);
if (client->closing && !client->half_closed)
if (client->flushing && !client->half_closed)
{
if (!shutdown (client->socket_fd, SHUT_WR))
client->half_closed = true;
@@ -2023,8 +2037,8 @@ client_new (EV_P_ size_t size, int sock_fd)
struct client *self = xcalloc (1, size);
self->write_queue = write_queue_make ();
ev_timer_init (&self->flush_timeout_watcher, on_client_timeout, 5., 0.);
self->flush_timeout_watcher.data = self;
ev_timer_init (&self->close_timeout_watcher, on_client_timeout, 5., 0.);
self->close_timeout_watcher.data = self;
set_blocking (sock_fd, false);
self->socket_fd = sock_fd;
@@ -2305,10 +2319,7 @@ static void
client_ws_close_cb (struct ws_handler *handler, bool half_close)
{
FIND_CONTAINER (self, handler, struct client_ws, handler);
if (half_close)
; // FIXME: we should probably call something like client_shutdown()
else
client_destroy (&self->client);
(half_close ? client_shutdown : client_destroy) (&self->client);
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -