xwayland/selection: use one X11 window per incoming transfer

This commit introduces logic for using a new X11 window for each
incoming transfer, rather than having a global window for each selection
source.

This eliminates a whole class of bugs involving multiple concurrent
incoming transfers.

For now, we retain the outgoing transfer queue, and the selection
source-specific windows to support it. Source-specific windows are no
longer used in the incoming path, and will be removed in a future PR.

Refs #1497.
This commit is contained in:
Tudor Brindus 2021-01-30 23:43:25 -05:00 committed by Simon Ser
parent 0977633457
commit 7964a313e8
5 changed files with 158 additions and 91 deletions

View file

@ -20,37 +20,43 @@ struct wlr_xwm_selection_transfer {
struct wl_array source_data;
int wl_client_fd;
struct wl_event_source *event_source;
struct wl_list link;
// when sending to x11
xcb_selection_request_event_t request;
struct wl_list outgoing_link;
// when receiving from x11
int property_start;
xcb_get_property_reply_t *property_reply;
xcb_window_t incoming_window;
};
struct wlr_xwm_selection {
struct wlr_xwm *xwm;
xcb_atom_t atom;
xcb_window_t window;
xcb_window_t owner;
xcb_timestamp_t timestamp;
struct wlr_xwm_selection_transfer incoming;
struct wl_list incoming;
struct wl_list outgoing;
};
struct wlr_xwm_selection_transfer *
xwm_selection_find_incoming_transfer_by_window(
struct wlr_xwm_selection *selection, xcb_window_t window);
void xwm_selection_transfer_remove_event_source(
struct wlr_xwm_selection_transfer *transfer);
void xwm_selection_transfer_close_wl_client_fd(
struct wlr_xwm_selection_transfer *transfer);
void xwm_selection_transfer_destroy_property_reply(
struct wlr_xwm_selection_transfer *transfer);
void xwm_selection_transfer_init(struct wlr_xwm_selection_transfer *transfer);
void xwm_selection_transfer_finish(struct wlr_xwm_selection_transfer *transfer);
bool xwm_selection_transfer_get_selection_property(
struct wlr_xwm_selection_transfer *transfer, bool delete);
void xwm_selection_transfer_init(struct wlr_xwm_selection_transfer *transfer,
struct wlr_xwm_selection *selection);
void xwm_selection_transfer_destroy(
struct wlr_xwm_selection_transfer *transfer);
void xwm_selection_transfer_destroy_outgoing(
struct wlr_xwm_selection_transfer *transfer);

View file

@ -103,6 +103,8 @@ struct wlr_xwm {
xcb_render_pictformat_t render_format_id;
xcb_cursor_t cursor;
// FIXME: need one per selection to simultaneously request both mimetypes,
// I think.
xcb_window_t selection_window;
struct wlr_xwm_selection clipboard_selection;
struct wlr_xwm_selection primary_selection;

View file

@ -11,13 +11,84 @@
#include "xwayland/selection.h"
#include "xwayland/xwm.h"
static struct wlr_xwm_selection_transfer *
xwm_selection_transfer_create_incoming(struct wlr_xwm_selection *selection) {
struct wlr_xwm_selection_transfer *transfer = calloc(1, sizeof(*transfer));
if (!transfer) {
return NULL;
}
xwm_selection_transfer_init(transfer, selection);
wl_list_insert(&selection->incoming, &transfer->link);
struct wlr_xwm *xwm = selection->xwm;
transfer->incoming_window = xcb_generate_id(xwm->xcb_conn);
xcb_create_window(
xwm->xcb_conn,
XCB_COPY_FROM_PARENT,
transfer->incoming_window,
xwm->screen->root,
0, 0,
10, 10,
0,
XCB_WINDOW_CLASS_INPUT_OUTPUT,
xwm->screen->root_visual,
XCB_CW_EVENT_MASK, (uint32_t[]){
XCB_EVENT_MASK_SUBSTRUCTURE_NOTIFY | XCB_EVENT_MASK_PROPERTY_CHANGE
}
);
xcb_flush(xwm->xcb_conn);
return transfer;
}
struct wlr_xwm_selection_transfer *
xwm_selection_find_incoming_transfer_by_window(
struct wlr_xwm_selection *selection, xcb_window_t window) {
struct wlr_xwm_selection_transfer *transfer;
wl_list_for_each(transfer, &selection->incoming, link) {
if (transfer->incoming_window == window) {
return transfer;
}
}
return NULL;
}
static bool xwm_selection_transfer_get_incoming_selection_property(
struct wlr_xwm_selection_transfer *transfer, bool delete) {
struct wlr_xwm *xwm = transfer->selection->xwm;
xcb_get_property_cookie_t cookie = xcb_get_property(
xwm->xcb_conn,
delete,
transfer->incoming_window,
xwm->atoms[WL_SELECTION],
XCB_GET_PROPERTY_TYPE_ANY,
0, // offset
0x1fffffff // length
);
transfer->property_start = 0;
transfer->property_reply =
xcb_get_property_reply(xwm->xcb_conn, cookie, NULL);
if (!transfer->property_reply) {
wlr_log(WLR_ERROR, "cannot get selection property");
return false;
}
return true;
}
static void xwm_notify_ready_for_next_incr_chunk(
struct wlr_xwm_selection_transfer *transfer) {
struct wlr_xwm *xwm = transfer->selection->xwm;
assert(transfer->incr);
wlr_log(WLR_DEBUG, "deleting property");
xcb_delete_property(xwm->xcb_conn, transfer->selection->window,
xcb_delete_property(xwm->xcb_conn, transfer->incoming_window,
xwm->atoms[WL_SELECTION]);
xcb_flush(xwm->xcb_conn);
@ -40,7 +111,7 @@ static int write_selection_property_to_wl_client(int fd, uint32_t mask,
ssize_t len = write(fd, property + transfer->property_start, remainder);
if (len == -1) {
wlr_log_errno(WLR_ERROR, "write error to target fd %d", fd);
xwm_selection_transfer_finish(transfer);
xwm_selection_transfer_destroy(transfer);
return 0;
}
@ -56,7 +127,7 @@ static int write_selection_property_to_wl_client(int fd, uint32_t mask,
xwm_notify_ready_for_next_incr_chunk(transfer);
} else {
wlr_log(WLR_DEBUG, "transfer complete");
xwm_selection_transfer_finish(transfer);
xwm_selection_transfer_destroy(transfer);
}
return 0;
@ -93,7 +164,7 @@ void xwm_get_incr_chunk(struct wlr_xwm_selection_transfer *transfer) {
return;
}
if (!xwm_selection_transfer_get_selection_property(transfer, false)) {
if (!xwm_selection_transfer_get_incoming_selection_property(transfer, false)) {
return;
}
@ -101,15 +172,15 @@ void xwm_get_incr_chunk(struct wlr_xwm_selection_transfer *transfer) {
xwm_write_selection_property_to_wl_client(transfer);
} else {
wlr_log(WLR_DEBUG, "incremental transfer complete");
xwm_selection_transfer_finish(transfer);
xwm_selection_transfer_destroy(transfer);
}
}
static void xwm_selection_get_data(struct wlr_xwm_selection *selection) {
struct wlr_xwm *xwm = selection->xwm;
struct wlr_xwm_selection_transfer *transfer = &selection->incoming;
static void xwm_selection_transfer_get_data(
struct wlr_xwm_selection_transfer *transfer) {
struct wlr_xwm *xwm = transfer->selection->xwm;
if (!xwm_selection_transfer_get_selection_property(transfer, true)) {
if (!xwm_selection_transfer_get_incoming_selection_property(transfer, true)) {
return;
}
@ -127,7 +198,6 @@ static void source_send(struct wlr_xwm_selection *selection,
struct wl_array *mime_types, struct wl_array *mime_types_atoms,
const char *requested_mime_type, int fd) {
struct wlr_xwm *xwm = selection->xwm;
struct wlr_xwm_selection_transfer *transfer = &selection->incoming;
xcb_atom_t *atoms = mime_types_atoms->data;
bool found = false;
@ -150,23 +220,16 @@ static void source_send(struct wlr_xwm_selection *selection,
return;
}
// FIXME: we currently can't handle two X11-to-Wayland transfers at once due
// to reusing the same X11 window. Proceeding further here would lead us to
// lose track of the current `transfer->wl_client_fd` and use-after-free
// during cleanup. This doesn't happen often, but bail now to avoid a
// compositor crash later.
if (transfer->wl_client_fd >= 0) {
wlr_log(WLR_ERROR, "source_send fd %d, but %d already in progress", fd,
transfer->wl_client_fd);
if (transfer->wl_client_fd != fd) {
close(fd);
}
struct wlr_xwm_selection_transfer *transfer =
xwm_selection_transfer_create_incoming(selection);
if (!transfer) {
wlr_log(WLR_ERROR, "Cannot create transfer");
close(fd);
return;
}
xcb_convert_selection(xwm->xcb_conn,
selection->window,
transfer->incoming_window,
selection->atom,
mime_type_atom,
xwm->atoms[WL_SELECTION],
@ -269,7 +332,7 @@ static bool source_get_targets(struct wlr_xwm_selection *selection,
XCB_GET_PROPERTY_TYPE_ANY,
0, // offset
4096 // length
);
);
xcb_get_property_reply_t *reply =
xcb_get_property_reply(xwm->xcb_conn, cookie, NULL);
@ -395,23 +458,26 @@ void xwm_handle_selection_notify(struct wlr_xwm *xwm,
return;
}
struct wlr_xwm_selection_transfer *transfer =
xwm_selection_find_incoming_transfer_by_window(selection, event->requestor);
if (event->property == XCB_ATOM_NONE) {
wlr_log(WLR_ERROR, "convert selection failed");
xwm_selection_transfer_finish(&selection->incoming);
if (transfer) {
wlr_log(WLR_ERROR, "convert selection failed");
xwm_selection_transfer_destroy(transfer);
}
} else if (event->target == xwm->atoms[TARGETS]) {
// No xwayland surface focused, deny access to clipboard
if (xwm->focus_surface == NULL) {
wlr_log(WLR_DEBUG, "denying write access to clipboard: "
"no xwayland surface focused");
// Would leak this transfer otherwise. Should never happen.
assert(selection->incoming.wl_client_fd < 0);
return;
}
// This sets the Wayland clipboard (by calling wlr_seat_set_selection)
xwm_selection_get_targets(selection);
} else {
xwm_selection_get_data(selection);
} else if (transfer) {
xwm_selection_transfer_get_data(transfer);
}
}
@ -428,8 +494,7 @@ int xwm_handle_xfixes_selection_notify(struct wlr_xwm *xwm,
if (event->owner == XCB_WINDOW_NONE) {
if (selection->owner != selection->window) {
// A real X client selection went away, not our
// proxy selection
// A real X client selection went away, not our proxy selection
if (selection == &xwm->clipboard_selection) {
wlr_seat_request_set_selection(xwm->seat, NULL, NULL,
wl_display_next_serial(xwm->xwayland->wl_display));
@ -450,22 +515,23 @@ int xwm_handle_xfixes_selection_notify(struct wlr_xwm *xwm,
selection->owner = event->owner;
// We have to use XCB_TIME_CURRENT_TIME when we claim the
// selection, so grab the actual timestamp here so we can
// answer TIMESTAMP conversion requests correctly.
if (event->owner == selection->window) {
// We have to use XCB_TIME_CURRENT_TIME when we claim the selection, so
// grab the actual timestamp here so we can answer TIMESTAMP conversion
// requests correctly.
selection->timestamp = event->timestamp;
return 1;
}
struct wlr_xwm_selection_transfer *transfer = &selection->incoming;
transfer->incr = false;
// doing this will give a selection notify where we actually handle the sync
xcb_convert_selection(xwm->xcb_conn, selection->window,
xcb_convert_selection(
xwm->xcb_conn,
selection->window,
selection->atom,
xwm->atoms[TARGETS],
xwm->atoms[WL_SELECTION],
event->timestamp);
event->timestamp
);
xcb_flush(xwm->xcb_conn);
return 1;

View file

@ -59,8 +59,7 @@ static struct wlr_xwm_selection_transfer *xwm_selection_transfer_get_first(
struct wlr_xwm_selection *selection) {
struct wlr_xwm_selection_transfer *first = NULL;
if (!wl_list_empty(&selection->outgoing)) {
first = wl_container_of(selection->outgoing.prev, first,
outgoing_link);
first = wl_container_of(selection->outgoing.prev, first, link);
}
return first;
@ -70,7 +69,7 @@ void xwm_selection_transfer_destroy_outgoing(
struct wlr_xwm_selection_transfer *transfer) {
struct wlr_xwm_selection *selection = transfer->selection;
bool was_first = transfer == xwm_selection_transfer_get_first(selection);
wl_list_remove(&transfer->outgoing_link);
wl_list_remove(&transfer->link);
wlr_log(WLR_DEBUG, "Destroying transfer %p", transfer);
// Start next queued transfer if we just removed the active one.
@ -297,8 +296,7 @@ static bool xwm_selection_send_data(struct wlr_xwm_selection *selection,
return false;
}
xwm_selection_transfer_init(transfer);
transfer->selection = selection;
xwm_selection_transfer_init(transfer, selection);
transfer->request = *req;
wl_array_init(&transfer->source_data);
@ -325,7 +323,7 @@ static bool xwm_selection_send_data(struct wlr_xwm_selection *selection,
// from it. It appears to only ever read from the latest, so purge stale
// transfers to prevent clipboard hangs.
struct wlr_xwm_selection_transfer *outgoing, *tmp;
wl_list_for_each_safe(outgoing, tmp, &selection->outgoing, outgoing_link) {
wl_list_for_each_safe(outgoing, tmp, &selection->outgoing, link) {
if (transfer->request.requestor == outgoing->request.requestor) {
wlr_log(WLR_DEBUG, "Destroying stale transfer %p", outgoing);
xwm_selection_send_notify(selection->xwm, &outgoing->request, false);
@ -333,7 +331,7 @@ static bool xwm_selection_send_data(struct wlr_xwm_selection *selection,
}
}
wl_list_insert(&selection->outgoing, &transfer->outgoing_link);
wl_list_insert(&selection->outgoing, &transfer->link);
// We can only handle one transfer at a time
if (wl_list_length(&selection->outgoing) == 1) {
@ -341,7 +339,7 @@ static bool xwm_selection_send_data(struct wlr_xwm_selection *selection,
xwm_selection_transfer_start_outgoing(transfer);
} else {
struct wlr_xwm_selection_transfer *outgoing;
wl_list_for_each(outgoing, &selection->outgoing, outgoing_link) {
wl_list_for_each(outgoing, &selection->outgoing, link) {
wlr_log(WLR_DEBUG, "Transfer %p still queued", outgoing);
}
}
@ -477,7 +475,7 @@ void xwm_handle_selection_destroy_notify(struct wlr_xwm *xwm,
struct wlr_xwm_selection *selection = selections[i];
struct wlr_xwm_selection_transfer *outgoing, *tmp;
wl_list_for_each_safe(outgoing, tmp, &selection->outgoing, outgoing_link) {
wl_list_for_each_safe(outgoing, tmp, &selection->outgoing, link) {
if (event->window == outgoing->request.requestor) {
xwm_selection_transfer_destroy_outgoing(outgoing);
}

View file

@ -32,42 +32,30 @@ void xwm_selection_transfer_destroy_property_reply(
transfer->property_reply = NULL;
}
void xwm_selection_transfer_init(struct wlr_xwm_selection_transfer *transfer) {
void xwm_selection_transfer_init(struct wlr_xwm_selection_transfer *transfer,
struct wlr_xwm_selection *selection) {
transfer->selection = selection;
transfer->wl_client_fd = -1;
}
void xwm_selection_transfer_finish(
void xwm_selection_transfer_destroy(
struct wlr_xwm_selection_transfer *transfer) {
transfer->incr = false;
if (!transfer) {
return;
}
xwm_selection_transfer_destroy_property_reply(transfer);
xwm_selection_transfer_remove_event_source(transfer);
xwm_selection_transfer_close_wl_client_fd(transfer);
}
bool xwm_selection_transfer_get_selection_property(
struct wlr_xwm_selection_transfer *transfer, bool delete) {
struct wlr_xwm *xwm = transfer->selection->xwm;
xcb_get_property_cookie_t cookie = xcb_get_property(
xwm->xcb_conn,
delete,
transfer->selection->window,
xwm->atoms[WL_SELECTION],
XCB_GET_PROPERTY_TYPE_ANY,
0, // offset
0x1fffffff // length
);
transfer->property_start = 0;
transfer->property_reply =
xcb_get_property_reply(xwm->xcb_conn, cookie, NULL);
if (!transfer->property_reply) {
wlr_log(WLR_ERROR, "cannot get selection property");
return false;
if (transfer->incoming_window) {
struct wlr_xwm *xwm = transfer->selection->xwm;
xcb_destroy_window(xwm->xcb_conn, transfer->incoming_window);
xcb_flush(xwm->xcb_conn);
}
return true;
wl_list_remove(&transfer->link);
free(transfer);
}
xcb_atom_t xwm_mime_type_to_atom(struct wlr_xwm *xwm, char *mime_type) {
@ -123,17 +111,22 @@ static int xwm_handle_selection_property_notify(struct wlr_xwm *xwm,
for (size_t i = 0; i < sizeof(selections)/sizeof(selections[0]); ++i) {
struct wlr_xwm_selection *selection = selections[i];
if (event->window == selection->window) {
if (event->state == XCB_PROPERTY_NEW_VALUE &&
event->atom == xwm->atoms[WL_SELECTION] &&
selection->incoming.incr) {
xwm_get_incr_chunk(&selection->incoming);
if (event->state == XCB_PROPERTY_NEW_VALUE &&
event->atom == xwm->atoms[WL_SELECTION]) {
struct wlr_xwm_selection_transfer *transfer =
xwm_selection_find_incoming_transfer_by_window(selection,
event->window);
if (transfer) {
if (transfer->incr) {
xwm_get_incr_chunk(transfer);
}
return 1;
}
return 1;
}
struct wlr_xwm_selection_transfer *outgoing;
wl_list_for_each(outgoing, &selection->outgoing, outgoing_link) {
wl_list_for_each(outgoing, &selection->outgoing, link) {
if (event->window == outgoing->request.requestor) {
if (event->state == XCB_PROPERTY_DELETE &&
event->atom == outgoing->request.property &&
@ -184,9 +177,8 @@ void xwm_selection_init(struct wlr_xwm_selection *selection,
selection->xwm = xwm;
selection->atom = atom;
selection->window = xwm->selection_window;
selection->incoming.selection = selection;
wl_list_init(&selection->incoming);
wl_list_init(&selection->outgoing);
xwm_selection_transfer_init(&selection->incoming);
uint32_t mask =
XCB_XFIXES_SELECTION_EVENT_MASK_SET_SELECTION_OWNER |
@ -202,12 +194,15 @@ void xwm_selection_finish(struct wlr_xwm_selection *selection) {
}
struct wlr_xwm_selection_transfer *outgoing, *tmp;
wl_list_for_each_safe(outgoing, tmp, &selection->outgoing, outgoing_link) {
wl_list_for_each_safe(outgoing, tmp, &selection->outgoing, link) {
wlr_log(WLR_INFO, "destroyed pending transfer %p", outgoing);
xwm_selection_transfer_destroy_outgoing(outgoing);
}
xwm_selection_transfer_finish(&selection->incoming);
struct wlr_xwm_selection_transfer *incoming;
wl_list_for_each_safe(incoming, tmp, &selection->incoming, link) {
xwm_selection_transfer_destroy(incoming);
}
}
static void xwm_selection_set_owner(struct wlr_xwm_selection *selection,