int
libwebsocket_service_timeout_check(struct libwebsocket_context *context,
struct libwebsocket *wsi, unsigned int sec)
{
/*
* if extensions want in on it (eg, we are a mux parent)
* give them a chance to service child timeouts
*/
if (lws_ext_callback_for_each_active(wsi, LWS_EXT_CALLBACK_1HZ, NULL, sec) < 0)
return 0;
if (!wsi->pending_timeout)
return 0;
/*
* if we went beyond the allowed time, kill the
* connection
*/
if (sec > wsi->pending_timeout_limit) {
lwsl_info("TIMEDOUT WAITING on %d\n", wsi->pending_timeout);
libwebsocket_close_and_free_session(context,
wsi, LWS_CLOSE_STATUS_NOSTATUS);
return 1;
}
return 0;
}
int
libwebsocket_service_timeout_check(struct libwebsocket_context *context,
struct libwebsocket *wsi, unsigned int sec)
{
/*
* if extensions want in on it (eg, we are a mux parent)
* give them a chance to service child timeouts
*/
if (lws_ext_callback_for_each_active(wsi, LWS_EXT_CALLBACK_1HZ, NULL, sec) < 0)
return 0;
if (!wsi->pending_timeout)
return 0;
/*
* if we went beyond the allowed time, kill the
* connection
*/
if (sec > wsi->pending_timeout_limit) {
lwsl_info("TIMEDOUT WAITING on %d\n", wsi->pending_timeout);
/*
* Since he failed a timeout, he already had a chance to do
* something and was unable to... that includes situations like
* half closed connections. So process this "failed timeout"
* close as a violent death and don't try to do protocol
* cleanup like flush partials.
*/
wsi->socket_is_permanently_unusable = 1;
libwebsocket_close_and_free_session(context,
wsi, LWS_CLOSE_STATUS_NOSTATUS);
return 1;
}
return 0;
}
LWS_VISIBLE int
libwebsocket_callback_on_writable(struct libwebsocket_context *context,
struct libwebsocket *wsi)
{
#ifdef LWS_USE_HTTP2
struct libwebsocket *network_wsi, *wsi2;
int already;
lwsl_info("%s: %p\n", __func__, wsi);
if (wsi->mode != LWS_CONNMODE_HTTP2_SERVING)
goto network_sock;
if (wsi->u.http2.requested_POLLOUT) {
lwsl_info("already pending writable\n");
return 1;
}
if (wsi->u.http2.tx_credit <= 0) {
/*
* other side is not able to cope with us sending
* anything so no matter if we have POLLOUT on our side.
*
* Delay waiting for our POLLOUT until peer indicates he has
* space for more using tx window command in http2 layer
*/
lwsl_info("%s: %p: waiting_tx_credit (%d)\n", __func__, wsi, wsi->u.http2.tx_credit);
wsi->u.http2.waiting_tx_credit = 1;
return 0;
}
network_wsi = lws_http2_get_network_wsi(wsi);
already = network_wsi->u.http2.requested_POLLOUT;
/* mark everybody above him as requesting pollout */
wsi2 = wsi;
while (wsi2) {
wsi2->u.http2.requested_POLLOUT = 1;
lwsl_info("mark %p pending writable\n", wsi2);
wsi2 = wsi2->u.http2.parent_wsi;
}
/* for network action, act only on the network wsi */
wsi = network_wsi;
if (already)
return 1;
network_sock:
#endif
(void)context;
if (lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_REQUEST_ON_WRITEABLE, NULL, 0))
return 1;
if (wsi->position_in_fds_table < 0) {
lwsl_err("%s: failed to find socket %d\n", __func__, wsi->sock);
return -1;
}
if (lws_change_pollfd(wsi, 0, LWS_POLLOUT))
return -1;
lws_libev_io(context, wsi, LWS_EV_START | LWS_EV_WRITE);
return 1;
}
void
libwebsocket_close_and_free_session(struct libwebsocket_context *context,
struct libwebsocket *wsi, enum lws_close_status reason)
{
int n, m, ret;
int old_state;
unsigned char buf[LWS_SEND_BUFFER_PRE_PADDING + 2 +
LWS_SEND_BUFFER_POST_PADDING];
struct lws_tokens eff_buf;
if (!wsi)
return;
old_state = wsi->state;
if (wsi->socket_is_permanently_unusable ||
reason == LWS_CLOSE_STATUS_NOSTATUS_CONTEXT_DESTROY)
goto just_kill_connection;
switch (old_state) {
case WSI_STATE_DEAD_SOCKET:
return;
/* we tried the polite way... */
case WSI_STATE_AWAITING_CLOSE_ACK:
goto just_kill_connection;
case WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE:
if (wsi->truncated_send_len) {
libwebsocket_callback_on_writable(context, wsi);
return;
}
lwsl_info("wsi %p completed WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE\n", wsi);
goto just_kill_connection;
default:
if (wsi->truncated_send_len) {
lwsl_info("wsi %p entering WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE\n", wsi);
wsi->state = WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE;
libwebsocket_set_timeout(wsi, PENDING_FLUSH_STORED_SEND_BEFORE_CLOSE, 5);
return;
}
break;
}
wsi->u.ws.close_reason = reason;
if (wsi->mode == LWS_CONNMODE_WS_CLIENT_WAITING_CONNECT ||
wsi->mode == LWS_CONNMODE_WS_CLIENT_ISSUE_HANDSHAKE) {
context->protocols[0].callback(context, wsi,
LWS_CALLBACK_CLIENT_CONNECTION_ERROR, wsi->user_space, NULL, 0);
goto just_kill_connection;
}
if (wsi->mode == LWS_CONNMODE_HTTP_SERVING)
context->protocols[0].callback(context, wsi,
LWS_CALLBACK_CLOSED_HTTP, wsi->user_space, NULL, 0);
if (wsi->mode == LWS_CONNMODE_HTTP_SERVING_ACCEPTED) {
if (wsi->u.http.fd != LWS_INVALID_FILE) {
// TODO: If we're just closing with LWS_CLOSE_STATUS_NOSTATUS_CONTEXT_DESTROY this file descriptor might leak?
lwsl_debug("closing http file\n");
compatible_file_close(wsi->u.http.fd);
wsi->u.http.fd = LWS_INVALID_FILE;
context->protocols[0].callback(context, wsi,
LWS_CALLBACK_CLOSED_HTTP, wsi->user_space, NULL, 0);
}
}
/*
* are his extensions okay with him closing? Eg he might be a mux
* parent and just his ch1 aspect is closing?
*/
if (lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_CHECK_OK_TO_REALLY_CLOSE, NULL, 0) > 0) {
lwsl_ext("extension vetoed close\n");
return;
}
/*
* flush any tx pending from extensions, since we may send close packet
* if there are problems with send, just nuke the connection
*/
do {
ret = 0;
eff_buf.token = NULL;
eff_buf.token_len = 0;
/* show every extension the new incoming data */
m = lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_FLUSH_PENDING_TX, &eff_buf, 0);
if (m < 0) {
lwsl_ext("Extension reports fatal error\n");
goto just_kill_connection;
}
if (m)
/*
* at least one extension told us he has more
* to spill, so we will go around again after
*/
ret = 1;
/* assuming they left us something to send, send it */
if (eff_buf.token_len)
if (lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
eff_buf.token_len) != eff_buf.token_len) {
lwsl_debug("close: ext spill failed\n");
goto just_kill_connection;
}
} while (ret);
/*
* signal we are closing, libwebsocket_write will
* add any necessary version-specific stuff. If the write fails,
* no worries we are closing anyway. If we didn't initiate this
* close, then our state has been changed to
* WSI_STATE_RETURNED_CLOSE_ALREADY and we will skip this.
*
* Likewise if it's a second call to close this connection after we
* sent the close indication to the peer already, we are in state
* WSI_STATE_AWAITING_CLOSE_ACK and will skip doing this a second time.
*/
if (old_state == WSI_STATE_ESTABLISHED &&
reason != LWS_CLOSE_STATUS_NOSTATUS &&
reason != LWS_CLOSE_STATUS_NOSTATUS_CONTEXT_DESTROY) {
lwsl_debug("sending close indication...\n");
/* make valgrind happy */
memset(buf, 0, sizeof(buf));
n = libwebsocket_write(wsi,
&buf[LWS_SEND_BUFFER_PRE_PADDING + 2],
0, LWS_WRITE_CLOSE);
if (n >= 0) {
/*
* we have sent a nice protocol level indication we
* now wish to close, we should not send anything more
*/
wsi->state = WSI_STATE_AWAITING_CLOSE_ACK;
/*
* ...and we should wait for a reply for a bit
* out of politeness
*/
libwebsocket_set_timeout(wsi,
PENDING_TIMEOUT_CLOSE_ACK, 1);
lwsl_debug("sent close indication, awaiting ack\n");
return;
}
lwsl_info("close: sending close packet failed, hanging up\n");
/* else, the send failed and we should just hang up */
}
just_kill_connection:
lwsl_debug("close: just_kill_connection\n");
/*
* we won't be servicing or receiving anything further from this guy
* delete socket from the internal poll list if still present
*/
lws_ssl_remove_wsi_from_buffered_list(context, wsi);
// checking return redundant since we anyway close
remove_wsi_socket_from_fds(context, wsi);
wsi->state = WSI_STATE_DEAD_SOCKET;
lws_free2(wsi->rxflow_buffer);
lws_free_header_table(wsi);
if ((old_state == WSI_STATE_ESTABLISHED ||
wsi->mode == LWS_CONNMODE_WS_SERVING ||
wsi->mode == LWS_CONNMODE_WS_CLIENT)) {
lws_free2(wsi->u.ws.rx_user_buffer);
if (wsi->truncated_send_malloc) {
/* not going to be completed... nuke it */
lws_free2(wsi->truncated_send_malloc);
wsi->truncated_send_len = 0;
}
if (wsi->u.ws.ping_payload_buf) {
lws_free2(wsi->u.ws.ping_payload_buf);
wsi->u.ws.ping_payload_alloc = 0;
wsi->u.ws.ping_payload_len = 0;
wsi->u.ws.ping_pending_flag = 0;
}
}
/* tell the user it's all over for this guy */
if (wsi->protocol && wsi->protocol->callback &&
((old_state == WSI_STATE_ESTABLISHED) ||
(old_state == WSI_STATE_RETURNED_CLOSE_ALREADY) ||
(old_state == WSI_STATE_AWAITING_CLOSE_ACK) ||
(old_state == WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE))) {
lwsl_debug("calling back CLOSED\n");
wsi->protocol->callback(context, wsi, LWS_CALLBACK_CLOSED,
wsi->user_space, NULL, 0);
} else if (wsi->mode == LWS_CONNMODE_HTTP_SERVING_ACCEPTED) {
lwsl_debug("calling back CLOSED_HTTP\n");
context->protocols[0].callback(context, wsi,
LWS_CALLBACK_CLOSED_HTTP, wsi->user_space, NULL, 0 );
} else if (wsi->mode == LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY ||
wsi->mode == LWS_CONNMODE_WS_CLIENT_WAITING_CONNECT) {
lwsl_debug("Connection closed before server reply\n");
context->protocols[0].callback(context, wsi,
LWS_CALLBACK_CLIENT_CONNECTION_ERROR,
wsi->user_space, NULL, 0 );
} else
lwsl_debug("not calling back closed mode=%d state=%d\n",
wsi->mode, old_state);
/* deallocate any active extension contexts */
if (lws_ext_callback_for_each_active(wsi, LWS_EXT_CALLBACK_DESTROY, NULL, 0) < 0)
lwsl_warn("extension destruction failed\n");
#ifndef LWS_NO_EXTENSIONS
for (n = 0; n < wsi->count_active_extensions; n++)
lws_free(wsi->active_extensions_user[n]);
#endif
/*
* inform all extensions in case they tracked this guy out of band
* even though not active on him specifically
*/
if (lws_ext_callback_for_each_extension_type(context, wsi,
LWS_EXT_CALLBACK_DESTROY_ANY_WSI_CLOSING, NULL, 0) < 0)
lwsl_warn("ext destroy wsi failed\n");
/* lwsl_info("closing fd=%d\n", wsi->sock); */
if (!lws_ssl_close(wsi) && wsi->sock >= 0) {
n = shutdown(wsi->sock, SHUT_RDWR);
if (n)
lwsl_debug("closing: shutdown ret %d\n", LWS_ERRNO);
n = compatible_close(wsi->sock);
if (n)
lwsl_debug("closing: close ret %d\n", LWS_ERRNO);
}
/* outermost destroy notification for wsi (user_space still intact) */
context->protocols[0].callback(context, wsi,
LWS_CALLBACK_WSI_DESTROY, wsi->user_space, NULL, 0);
lws_free_wsi(wsi);
}
int lws_issue_raw(struct libwebsocket *wsi, unsigned char *buf, size_t len)
{
struct libwebsocket_context *context = wsi->protocol->owning_server;
int n;
size_t real_len = len;
int m;
if (!len)
return 0;
/* just ignore sends after we cleared the truncation buffer */
if (wsi->state == WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE &&
!wsi->truncated_send_len)
return len;
if (wsi->truncated_send_len && (buf < wsi->truncated_send_malloc ||
buf > (wsi->truncated_send_malloc +
wsi->truncated_send_len +
wsi->truncated_send_offset))) {
lwsl_err("****** %x Sending new, pending truncated ...\n", wsi);
assert(0);
}
m = lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_PACKET_TX_DO_SEND, &buf, len);
if (m < 0)
return -1;
if (m) /* handled */ {
n = m;
goto handle_truncated_send;
}
if (wsi->sock < 0)
lwsl_warn("** error invalid sock but expected to send\n");
/*
* nope, send it on the socket directly
*/
lws_latency_pre(context, wsi);
n = lws_ssl_capable_write(wsi, buf, len);
lws_latency(context, wsi, "send lws_issue_raw", n, n == len);
switch (n) {
case LWS_SSL_CAPABLE_ERROR:
/* we're going to close, let close know sends aren't possible */
wsi->socket_is_permanently_unusable = 1;
return -1;
case LWS_SSL_CAPABLE_MORE_SERVICE:
/* nothing got sent, not fatal, retry the whole thing later */
n = 0;
break;
}
handle_truncated_send:
/*
* we were already handling a truncated send?
*/
if (wsi->truncated_send_len) {
lwsl_info("***** %x partial send moved on by %d (vs %d)\n",
wsi, n, real_len);
wsi->truncated_send_offset += n;
wsi->truncated_send_len -= n;
if (!wsi->truncated_send_len) {
lwsl_info("***** %x partial send completed\n", wsi);
/* done with it, but don't free it */
n = real_len;
if (wsi->state == WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
lwsl_info("***** %x signalling to close now\n", wsi);
return -1; /* retry closing now */
}
}
/* always callback on writeable */
libwebsocket_callback_on_writable(
wsi->protocol->owning_server, wsi);
return n;
}
if (n == real_len)
/* what we just sent went out cleanly */
return n;
if (n && wsi->u.ws.clean_buffer)
/*
* This buffer unaffected by extension rewriting.
* It means the user code is expected to deal with
* partial sends. (lws knows the header was already
* sent, so on next send will just resume sending
* payload)
*/
return n;
/*
* Newly truncated send. Buffer the remainder (it will get
* first priority next time the socket is writable)
*/
lwsl_info("***** %x new partial sent %d from %d total\n",
wsi, n, real_len);
/*
* - if we still have a suitable malloc lying around, use it
* - or, if too small, reallocate it
* - or, if no buffer, create it
*/
if (!wsi->truncated_send_malloc ||
real_len - n > wsi->truncated_send_allocation) {
lws_free(wsi->truncated_send_malloc);
wsi->truncated_send_allocation = real_len - n;
wsi->truncated_send_malloc = lws_malloc(real_len - n);
if (!wsi->truncated_send_malloc) {
lwsl_err("truncated send: unable to malloc %d\n",
real_len - n);
return -1;
}
}
wsi->truncated_send_offset = 0;
wsi->truncated_send_len = real_len - n;
memcpy(wsi->truncated_send_malloc, buf + n, real_len - n);
/* since something buffered, force it to get another chance to send */
libwebsocket_callback_on_writable(wsi->protocol->owning_server, wsi);
return real_len;
}
LWS_VISIBLE int libwebsocket_write(struct libwebsocket *wsi, unsigned char *buf,
size_t len, enum libwebsocket_write_protocol protocol)
{
int n;
int pre = 0;
int post = 0;
int masked7 = wsi->mode == LWS_CONNMODE_WS_CLIENT;
unsigned char *dropmask = NULL;
unsigned char is_masked_bit = 0;
size_t orig_len = len;
struct lws_tokens eff_buf;
if (len == 0 && protocol != LWS_WRITE_CLOSE &&
protocol != LWS_WRITE_PING && protocol != LWS_WRITE_PONG) {
lwsl_warn("zero length libwebsocket_write attempt\n");
return 0;
}
if (protocol == LWS_WRITE_HTTP ||
protocol == LWS_WRITE_HTTP_FINAL ||
protocol == LWS_WRITE_HTTP_HEADERS)
goto send_raw;
/* websocket protocol, either binary or text */
if (wsi->state != WSI_STATE_ESTABLISHED)
return -1;
/* if we are continuing a frame that already had its header done */
if (wsi->u.ws.inside_frame)
goto do_more_inside_frame;
wsi->u.ws.clean_buffer = 1;
/*
* give a chance to the extensions to modify payload
* pre-TX mangling is not allowed to truncate
*/
eff_buf.token = (char *)buf;
eff_buf.token_len = len;
switch (protocol) {
case LWS_WRITE_PING:
case LWS_WRITE_PONG:
case LWS_WRITE_CLOSE:
break;
default:
if (lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_PAYLOAD_TX, &eff_buf, 0) < 0)
return -1;
}
/*
* an extension did something we need to keep... for example, if
* compression extension, it has already updated its state according
* to this being issued
*/
if ((char *)buf != eff_buf.token)
/*
* extension recreated it:
* need to buffer this if not all sent
*/
wsi->u.ws.clean_buffer = 0;
buf = (unsigned char *)eff_buf.token;
len = eff_buf.token_len;
switch (wsi->ietf_spec_revision) {
case 13:
if (masked7) {
pre += 4;
dropmask = &buf[0 - pre];
is_masked_bit = 0x80;
}
switch (protocol & 0xf) {
case LWS_WRITE_TEXT:
n = LWS_WS_OPCODE_07__TEXT_FRAME;
break;
case LWS_WRITE_BINARY:
n = LWS_WS_OPCODE_07__BINARY_FRAME;
break;
case LWS_WRITE_CONTINUATION:
n = LWS_WS_OPCODE_07__CONTINUATION;
break;
case LWS_WRITE_CLOSE:
n = LWS_WS_OPCODE_07__CLOSE;
/*
* 06+ has a 2-byte status code in network order
* we can do this because we demand post-buf
*/
if (wsi->u.ws.close_reason) {
/* reason codes count as data bytes */
buf -= 2;
buf[0] = wsi->u.ws.close_reason >> 8;
buf[1] = wsi->u.ws.close_reason;
len += 2;
}
break;
case LWS_WRITE_PING:
n = LWS_WS_OPCODE_07__PING;
break;
case LWS_WRITE_PONG:
n = LWS_WS_OPCODE_07__PONG;
break;
default:
lwsl_warn("lws_write: unknown write opc / protocol\n");
return -1;
}
if (!(protocol & LWS_WRITE_NO_FIN))
n |= 1 << 7;
if (len < 126) {
pre += 2;
buf[-pre] = n;
buf[-pre + 1] = len | is_masked_bit;
} else {
if (len < 65536) {
pre += 4;
buf[-pre] = n;
buf[-pre + 1] = 126 | is_masked_bit;
buf[-pre + 2] = len >> 8;
buf[-pre + 3] = len;
} else {
int
lws_handle_POLLOUT_event(struct libwebsocket_context *context,
struct libwebsocket *wsi, struct libwebsocket_pollfd *pollfd)
{
int n;
struct lws_tokens eff_buf;
#ifdef LWS_USE_HTTP2
struct libwebsocket *wsi2;
#endif
int ret;
int m;
int handled = 0;
/* pending truncated sends have uber priority */
if (wsi->truncated_send_len) {
if (lws_issue_raw(wsi, wsi->truncated_send_malloc +
wsi->truncated_send_offset,
wsi->truncated_send_len) < 0) {
lwsl_info("lws_handle_POLLOUT_event signalling to close\n");
return -1;
}
/* leave POLLOUT active either way */
return 0;
} else
if (wsi->state == WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE) {
lwsl_info("***** %x signalling to close in POLLOUT handler\n", wsi);
return -1; /* retry closing now */
}
#ifdef LWS_USE_HTTP2
/* protocol packets are next */
if (wsi->pps) {
lwsl_info("servicing pps %d\n", wsi->pps);
switch (wsi->pps) {
case LWS_PPS_HTTP2_MY_SETTINGS:
case LWS_PPS_HTTP2_ACK_SETTINGS:
lws_http2_do_pps_send(context, wsi);
break;
default:
break;
}
wsi->pps = LWS_PPS_NONE;
libwebsocket_rx_flow_control(wsi, 1);
return 0; /* leave POLLOUT active */
}
#endif
/* pending control packets have next priority */
if (wsi->state == WSI_STATE_ESTABLISHED && wsi->u.ws.ping_payload_len) {
n = libwebsocket_write(wsi,
&wsi->u.ws.ping_payload_buf[
LWS_SEND_BUFFER_PRE_PADDING],
wsi->u.ws.ping_payload_len,
LWS_WRITE_PONG);
if (n < 0)
return -1;
/* well he is sent, mark him done */
wsi->u.ws.ping_payload_len = 0;
/* leave POLLOUT active either way */
return 0;
}
/* if nothing critical, user can get the callback */
m = lws_ext_callback_for_each_active(wsi, LWS_EXT_CALLBACK_IS_WRITEABLE,
NULL, 0);
#ifndef LWS_NO_EXTENSIONS
if (!wsi->extension_data_pending || handled == 2)
goto user_service;
#endif
/*
* check in on the active extensions, see if they
* had pending stuff to spill... they need to get the
* first look-in otherwise sequence will be disordered
*
* NULL, zero-length eff_buf means just spill pending
*/
ret = 1;
while (ret == 1) {
/* default to nobody has more to spill */
ret = 0;
eff_buf.token = NULL;
eff_buf.token_len = 0;
/* give every extension a chance to spill */
m = lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_PACKET_TX_PRESEND,
&eff_buf, 0);
if (m < 0) {
lwsl_err("ext reports fatal error\n");
return -1;
}
if (m)
/*
* at least one extension told us he has more
* to spill, so we will go around again after
*/
ret = 1;
/* assuming they gave us something to send, send it */
if (eff_buf.token_len) {
n = lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
eff_buf.token_len);
if (n < 0) {
lwsl_info("closing from POLLOUT spill\n");
return -1;
}
/*
* Keep amount spilled small to minimize chance of this
*/
if (n != eff_buf.token_len) {
lwsl_err("Unable to spill ext %d vs %s\n",
eff_buf.token_len, n);
return -1;
}
} else
continue;
/* no extension has more to spill */
if (!ret)
continue;
/*
* There's more to spill from an extension, but we just sent
* something... did that leave the pipe choked?
*/
if (!lws_send_pipe_choked(wsi))
/* no we could add more */
continue;
lwsl_info("choked in POLLOUT service\n");
/*
* Yes, he's choked. Leave the POLLOUT masked on so we will
* come back here when he is unchoked. Don't call the user
* callback to enforce ordering of spilling, he'll get called
* when we come back here and there's nothing more to spill.
*/
return 0;
}
#ifndef LWS_NO_EXTENSIONS
wsi->extension_data_pending = 0;
user_service:
#endif
/* one shot */
if (pollfd) {
if (lws_change_pollfd(wsi, LWS_POLLOUT, 0)) {
lwsl_info("failled at set pollfd\n");
return 1;
}
lws_libev_io(context, wsi, LWS_EV_STOP | LWS_EV_WRITE);
}
#ifdef LWS_USE_HTTP2
/*
* we are the 'network wsi' for potentially many muxed child wsi with
* no network connection of their own, who have to use us for all their
* network actions. So we use a round-robin scheme to share out the
* POLLOUT notifications to our children.
*
* But because any child could exhaust the socket's ability to take
* writes, we can only let one child get notified each time.
*
* In addition children may be closed / deleted / added between POLLOUT
* notifications, so we can't hold pointers
*/
if (wsi->mode != LWS_CONNMODE_HTTP2_SERVING) {
lwsl_info("%s: non http2\n", __func__);
goto notify;
}
wsi->u.http2.requested_POLLOUT = 0;
if (!wsi->u.http2.initialized) {
lwsl_info("pollout on uninitialized http2 conn\n");
return 0;
}
lwsl_info("%s: doing children\n", __func__);
wsi2 = wsi;
do {
wsi2 = wsi2->u.http2.next_child_wsi;
lwsl_info("%s: child %p\n", __func__, wsi2);
if (!wsi2)
continue;
if (!wsi2->u.http2.requested_POLLOUT)
continue;
wsi2->u.http2.requested_POLLOUT = 0;
if (lws_calllback_as_writeable(context, wsi2)) {
lwsl_debug("Closing POLLOUT child\n");
libwebsocket_close_and_free_session(context, wsi2,
LWS_CLOSE_STATUS_NOSTATUS);
}
wsi2 = wsi;
} while (wsi2 != NULL && !lws_send_pipe_choked(wsi));
lwsl_info("%s: completed\n", __func__);
return 0;
notify:
#endif
return lws_calllback_as_writeable(context, wsi);
}
LWS_VISIBLE int
libwebsocket_service_fd(struct libwebsocket_context *context,
struct libwebsocket_pollfd *pollfd)
{
struct libwebsocket *wsi;
int n;
int m;
int listen_socket_fds_index = 0;
time_t now;
int timed_out = 0;
int our_fd = 0;
char draining_flow = 0;
int more;
struct lws_tokens eff_buf;
if (context->listen_service_fd)
listen_socket_fds_index = context->lws_lookup[
context->listen_service_fd]->position_in_fds_table;
/*
* you can call us with pollfd = NULL to just allow the once-per-second
* global timeout checks; if less than a second since the last check
* it returns immediately then.
*/
time(&now);
/* TODO: if using libev, we should probably use timeout watchers... */
if (context->last_timeout_check_s != now) {
context->last_timeout_check_s = now;
lws_plat_service_periodic(context);
/* global timeout check once per second */
if (pollfd)
our_fd = pollfd->fd;
for (n = 0; n < context->fds_count; n++) {
m = context->fds[n].fd;
wsi = context->lws_lookup[m];
if (!wsi)
continue;
if (libwebsocket_service_timeout_check(context, wsi, now))
/* he did time out... */
if (m == our_fd) {
/* it was the guy we came to service! */
timed_out = 1;
/* mark as handled */
if (pollfd)
pollfd->revents = 0;
}
}
}
/* the socket we came to service timed out, nothing to do */
if (timed_out)
return 0;
/* just here for timeout management? */
if (pollfd == NULL)
return 0;
/* no, here to service a socket descriptor */
wsi = context->lws_lookup[pollfd->fd];
if (wsi == NULL)
/* not lws connection ... leave revents alone and return */
return 0;
/*
* so that caller can tell we handled, past here we need to
* zero down pollfd->revents after handling
*/
/*
* deal with listen service piggybacking
* every listen_service_modulo services of other fds, we
* sneak one in to service the listen socket if there's anything waiting
*
* To handle connection storms, as found in ab, if we previously saw a
* pending connection here, it causes us to check again next time.
*/
if (context->listen_service_fd && pollfd !=
&context->fds[listen_socket_fds_index]) {
context->listen_service_count++;
if (context->listen_service_extraseen ||
context->listen_service_count ==
context->listen_service_modulo) {
context->listen_service_count = 0;
m = 1;
if (context->listen_service_extraseen > 5)
m = 2;
while (m--) {
/*
* even with extpoll, we prepared this
* internal fds for listen
*/
n = lws_poll_listen_fd(&context->fds[listen_socket_fds_index]);
if (n > 0) { /* there's a conn waiting for us */
libwebsocket_service_fd(context,
&context->
fds[listen_socket_fds_index]);
context->listen_service_extraseen++;
} else {
if (context->listen_service_extraseen)
context->
listen_service_extraseen--;
break;
}
}
}
}
/* handle session socket closed */
if ((!(pollfd->revents & LWS_POLLIN)) &&
(pollfd->revents & LWS_POLLHUP)) {
lwsl_debug("Session Socket %p (fd=%d) dead\n",
(void *)wsi, pollfd->fd);
goto close_and_handled;
}
/* okay, what we came here to do... */
switch (wsi->mode) {
case LWS_CONNMODE_HTTP_SERVING:
case LWS_CONNMODE_HTTP_SERVING_ACCEPTED:
case LWS_CONNMODE_SERVER_LISTENER:
case LWS_CONNMODE_SSL_ACK_PENDING:
n = lws_server_socket_service(context, wsi, pollfd);
if (n < 0)
goto close_and_handled;
goto handled;
case LWS_CONNMODE_WS_SERVING:
case LWS_CONNMODE_WS_CLIENT:
case LWS_CONNMODE_HTTP2_SERVING:
/* the guy requested a callback when it was OK to write */
if ((pollfd->revents & LWS_POLLOUT) &&
(wsi->state == WSI_STATE_ESTABLISHED || wsi->state == WSI_STATE_HTTP2_ESTABLISHED || wsi->state == WSI_STATE_HTTP2_ESTABLISHED_PRE_SETTINGS ||
wsi->state == WSI_STATE_FLUSHING_STORED_SEND_BEFORE_CLOSE) &&
lws_handle_POLLOUT_event(context, wsi, pollfd)) {
lwsl_info("libwebsocket_service_fd: closing\n");
goto close_and_handled;
}
if (wsi->rxflow_buffer &&
(wsi->rxflow_change_to & LWS_RXFLOW_ALLOW)) {
lwsl_info("draining rxflow\n");
/* well, drain it */
eff_buf.token = (char *)wsi->rxflow_buffer +
wsi->rxflow_pos;
eff_buf.token_len = wsi->rxflow_len - wsi->rxflow_pos;
draining_flow = 1;
goto drain;
}
/* any incoming data ready? */
if (!(pollfd->revents & LWS_POLLIN))
break;
eff_buf.token_len = lws_ssl_capable_read(context, wsi,
context->service_buffer,
sizeof(context->service_buffer));
switch (eff_buf.token_len) {
case 0:
lwsl_info("service_fd: closing due to 0 length read\n");
goto close_and_handled;
case LWS_SSL_CAPABLE_MORE_SERVICE:
lwsl_info("SSL Capable more service\n");
n = 0;
goto handled;
case LWS_SSL_CAPABLE_ERROR:
lwsl_info("Closing when error\n");
goto close_and_handled;
}
/*
* give any active extensions a chance to munge the buffer
* before parse. We pass in a pointer to an lws_tokens struct
* prepared with the default buffer and content length that's in
* there. Rather than rewrite the default buffer, extensions
* that expect to grow the buffer can adapt .token to
* point to their own per-connection buffer in the extension
* user allocation. By default with no extensions or no
* extension callback handling, just the normal input buffer is
* used then so it is efficient.
*/
eff_buf.token = (char *)context->service_buffer;
drain:
do {
more = 0;
m = lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_PACKET_RX_PREPARSE, &eff_buf, 0);
if (m < 0)
goto close_and_handled;
if (m)
more = 1;
/* service incoming data */
if (eff_buf.token_len) {
n = libwebsocket_read(context, wsi,
(unsigned char *)eff_buf.token,
eff_buf.token_len);
if (n < 0) {
/* we closed wsi */
n = 0;
goto handled;
}
}
eff_buf.token = NULL;
eff_buf.token_len = 0;
} while (more);
if (draining_flow && wsi->rxflow_buffer &&
wsi->rxflow_pos == wsi->rxflow_len) {
lwsl_info("flow buffer: drained\n");
lws_free2(wsi->rxflow_buffer);
/* having drained the rxflow buffer, can rearm POLLIN */
_libwebsocket_rx_flow_control(wsi); /* n ignored, needed for NO_SERVER case */
}
break;
default:
#ifdef LWS_NO_CLIENT
break;
#else
n = lws_client_socket_service(context, wsi, pollfd);
goto handled;
#endif
}
n = 0;
goto handled;
close_and_handled:
lwsl_debug("Close and handled\n");
libwebsocket_close_and_free_session(context, wsi,
LWS_CLOSE_STATUS_NOSTATUS);
n = 1;
handled:
pollfd->revents = 0;
return n;
}
int
lws_issue_raw_ext_access(struct libwebsocket *wsi,
unsigned char *buf, size_t len)
{
int ret;
struct lws_tokens eff_buf;
int m;
int n = 0;
eff_buf.token = (char *)buf;
eff_buf.token_len = len;
/*
* while we have original buf to spill ourselves, or extensions report
* more in their pipeline
*/
ret = 1;
while (ret == 1) {
/* default to nobody has more to spill */
ret = 0;
/* show every extension the new incoming data */
m = lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_PACKET_TX_PRESEND, &eff_buf, 0);
if (m < 0)
return -1;
if (m) /* handled */
ret = 1;
if ((char *)buf != eff_buf.token)
/*
* extension recreated it:
* need to buffer this if not all sent
*/
wsi->u.ws.clean_buffer = 0;
/* assuming they left us something to send, send it */
if (eff_buf.token_len) {
n = lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
eff_buf.token_len);
if (n < 0) {
lwsl_info("closing from ext access\n");
return -1;
}
/* always either sent it all or privately buffered */
if (wsi->u.ws.clean_buffer)
len = n;
}
lwsl_parser("written %d bytes to client\n", n);
/* no extension has more to spill? Then we can go */
if (!ret)
break;
/* we used up what we had */
eff_buf.token = NULL;
eff_buf.token_len = 0;
/*
* Did that leave the pipe choked?
* Or we had to hold on to some of it?
*/
if (!lws_send_pipe_choked(wsi) && !wsi->truncated_send_len)
/* no we could add more, lets's do that */
continue;
lwsl_debug("choked\n");
/*
* Yes, he's choked. Don't spill the rest now get a callback
* when he is ready to send and take care of it there
*/
libwebsocket_callback_on_writable(
wsi->protocol->owning_server, wsi);
wsi->extension_data_pending = 1;
ret = 0;
}
return len;
}
int
lws_handle_POLLOUT_event(struct libwebsocket_context *context,
struct libwebsocket *wsi, struct libwebsocket_pollfd *pollfd)
{
int n;
struct lws_tokens eff_buf;
int ret;
int m;
int handled = 0;
/* pending truncated sends have uber priority */
if (wsi->truncated_send_len) {
lws_issue_raw(wsi, wsi->truncated_send_malloc +
wsi->truncated_send_offset,
wsi->truncated_send_len);
/* leave POLLOUT active either way */
return 0;
}
m = lws_ext_callback_for_each_active(wsi, LWS_EXT_CALLBACK_IS_WRITEABLE,
NULL, 0);
if (handled == 1)
goto notify_action;
#ifndef LWS_NO_EXTENSIONS
if (!wsi->extension_data_pending || handled == 2)
goto user_service;
#endif
/*
* check in on the active extensions, see if they
* had pending stuff to spill... they need to get the
* first look-in otherwise sequence will be disordered
*
* NULL, zero-length eff_buf means just spill pending
*/
ret = 1;
while (ret == 1) {
/* default to nobody has more to spill */
ret = 0;
eff_buf.token = NULL;
eff_buf.token_len = 0;
/* give every extension a chance to spill */
m = lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_PACKET_TX_PRESEND,
&eff_buf, 0);
if (m < 0) {
lwsl_err("ext reports fatal error\n");
return -1;
}
if (m)
/*
* at least one extension told us he has more
* to spill, so we will go around again after
*/
ret = 1;
/* assuming they gave us something to send, send it */
if (eff_buf.token_len) {
n = lws_issue_raw(wsi, (unsigned char *)eff_buf.token,
eff_buf.token_len);
if (n < 0)
return -1;
/*
* Keep amount spilled small to minimize chance of this
*/
if (n != eff_buf.token_len) {
lwsl_err("Unable to spill ext %d vs %s\n",
eff_buf.token_len, n);
return -1;
}
} else
continue;
/* no extension has more to spill */
if (!ret)
continue;
/*
* There's more to spill from an extension, but we just sent
* something... did that leave the pipe choked?
*/
if (!lws_send_pipe_choked(wsi))
/* no we could add more */
continue;
lwsl_info("choked in POLLOUT service\n");
/*
* Yes, he's choked. Leave the POLLOUT masked on so we will
* come back here when he is unchoked. Don't call the user
* callback to enforce ordering of spilling, he'll get called
* when we come back here and there's nothing more to spill.
*/
return 0;
}
#ifndef LWS_NO_EXTENSIONS
wsi->extension_data_pending = 0;
user_service:
#endif
/* one shot */
if (pollfd) {
if (lws_change_pollfd(wsi, LWS_POLLOUT, 0))
return 1;
#ifdef LWS_USE_LIBEV
if (LWS_LIBEV_ENABLED(context))
ev_io_stop(context->io_loop,
(struct ev_io *)&wsi->w_write);
#endif /* LWS_USE_LIBEV */
}
notify_action:
if (wsi->mode == LWS_CONNMODE_WS_CLIENT)
n = LWS_CALLBACK_CLIENT_WRITEABLE;
else
n = LWS_CALLBACK_SERVER_WRITEABLE;
return user_callback_handle_rxflow(wsi->protocol->callback, context,
wsi, (enum libwebsocket_callback_reasons) n,
wsi->user_space, NULL, 0);
}
int lws_issue_raw(struct libwebsocket *wsi, unsigned char *buf, size_t len)
{
struct libwebsocket_context *context = wsi->protocol->owning_server;
int n;
size_t real_len = len;
int m;
if (!len)
return 0;
if (wsi->truncated_send_len && (buf < wsi->truncated_send_malloc ||
buf > (wsi->truncated_send_malloc +
wsi->truncated_send_len +
wsi->truncated_send_offset))) {
lwsl_err("****** %x Sending new, pending truncated ...\n", wsi);
assert(0);
}
m = lws_ext_callback_for_each_active(wsi,
LWS_EXT_CALLBACK_PACKET_TX_DO_SEND, &buf, len);
if (m < 0)
return -1;
if (m) /* handled */ {
n = m;
goto handle_truncated_send;
}
if (wsi->sock < 0)
lwsl_warn("** error invalid sock but expected to send\n");
/*
* nope, send it on the socket directly
*/
lws_latency_pre(context, wsi);
n = lws_ssl_capable_write(wsi, buf, len);
lws_latency(context, wsi, "send lws_issue_raw", n, n == len);
switch (n) {
case LWS_SSL_CAPABLE_ERROR:
return -1;
case LWS_SSL_CAPABLE_MORE_SERVICE:
n = 0;
goto handle_truncated_send;
}
handle_truncated_send:
/*
* already handling a truncated send?
*/
if (wsi->truncated_send_len) {
lwsl_info("***** %x partial send moved on by %d (vs %d)\n",
wsi, n, real_len);
wsi->truncated_send_offset += n;
wsi->truncated_send_len -= n;
if (!wsi->truncated_send_len) {
lwsl_info("***** %x partial send completed\n", wsi);
/* done with it, but don't free it */
n = real_len;
} else
libwebsocket_callback_on_writable(
wsi->protocol->owning_server, wsi);
return n;
}
if (n < real_len) {
if (n && wsi->u.ws.clean_buffer)
/*
* This buffer unaffected by extension rewriting.
* It means the user code is expected to deal with
* partial sends. (lws knows the header was already
* sent, so on next send will just resume sending
* payload)
*/
return n;
/*
* Newly truncated send. Buffer the remainder (it will get
* first priority next time the socket is writable)
*/
lwsl_info("***** %x new partial sent %d from %d total\n",
wsi, n, real_len);
/*
* - if we still have a suitable malloc lying around, use it
* - or, if too small, reallocate it
* - or, if no buffer, create it
*/
if (!wsi->truncated_send_malloc ||
real_len - n > wsi->truncated_send_allocation) {
if (wsi->truncated_send_malloc)
free(wsi->truncated_send_malloc);
wsi->truncated_send_allocation = real_len - n;
wsi->truncated_send_malloc = malloc(real_len - n);
if (!wsi->truncated_send_malloc) {
lwsl_err(
"truncated send: unable to malloc %d\n",
real_len - n);
return -1;
}
}
wsi->truncated_send_offset = 0;
wsi->truncated_send_len = real_len - n;
memcpy(wsi->truncated_send_malloc, buf + n, real_len - n);
libwebsocket_callback_on_writable(
wsi->protocol->owning_server, wsi);
return real_len;
}
return n;
}
