clients/dnd.c

   1 /*
   2  * Copyright © 2010 Kristian Høgsberg
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and its
   5  * documentation for any purpose is hereby granted without fee, provided that
   6  * the above copyright notice appear in all copies and that both that copyright
   7  * notice and this permission notice appear in supporting documentation, and
   8  * that the name of the copyright holders not be used in advertising or
   9  * publicity pertaining to distribution of the software without specific,
  10  * written prior permission.  The copyright holders make no representations
  11  * about the suitability of this software for any purpose.  It is provided "as
  12  * is" without express or implied warranty.
  13  *
  14  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  15  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  16  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  17  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  18  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  19  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  20  * OF THIS SOFTWARE.
  21  */
  22
  23 #include <stdint.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <fcntl.h>
  28 #include <unistd.h>
  29 #include <math.h>
  30 #include <sys/time.h>
  31 #include <cairo.h>
  32 #include <glib.h>
  33 #include <gdk-pixbuf/gdk-pixbuf.h>
  34
  35 #include "wayland-client.h"
  36 #include "wayland-glib.h"
  37
  38 #include "window.h"
  39
  40 struct dnd {
  41         struct window *window;
  42         struct display *display;
  43         uint32_t key;
  44         struct item *items[16];
  45 };
  46
  47 struct dnd_drag {
  48         cairo_surface_t *translucent;
  49         cairo_surface_t *opaque;
  50         int hotspot_x, hotspot_y;
  51         struct dnd *dnd;
  52         struct input *input;
  53         uint32_t time;
  54         struct item *item;
  55         int x_offset, y_offset;
  56         const char *mime_type;
  57 };
  58
  59 struct dnd_offer {
  60         int refcount;
  61         struct dnd *dnd;
  62         struct wl_array types;
  63         const char *drag_type;
  64         uint32_t tag;
  65         int x, y;
  66 };
  67
  68 struct item {
  69         cairo_surface_t *surface;
  70         int seed;
  71         int x, y;
  72 };
  73
  74 struct dnd_flower_message {
  75         int seed, x_offset, y_offset;
  76 };
  77
  78
  79 static const int item_width = 64;
  80 static const int item_height = 64;
  81 static const int item_padding = 16;
  82
  83 static struct item *
  84 item_create(struct display *display, int x, int y, int seed)
  85 {
  86         struct item *item;
  87         struct timeval tv;
  88
  89         item = malloc(sizeof *item);
  90         if (item == NULL)
  91                 return NULL;
  92
  93
  94         gettimeofday(&tv, NULL);
  95         item->seed = seed ? seed : tv.tv_usec;
  96         srandom(item->seed);
  97
  98         const int petal_count = 3 + random() % 5;
  99         const double r1 = 20 + random() % 10;
 100         const double r2 = 5 + random() % 12;
 101         const double u = (10 + random() % 90) / 100.0;
 102         const double v = (random() % 90) / 100.0;
 103
 104         cairo_t *cr;
 105         int i;
 106         double t, dt = 2 * M_PI / (petal_count * 2);
 107         double x1, y1, x2, y2, x3, y3;
 108         struct rectangle rect;
 109
 110
 111         rect.width = item_width;
 112         rect.height = item_height;
 113         item->surface = display_create_surface(display, NULL, &rect);
 114
 115         item->x = x;
 116         item->y = y;
 117
 118         cr = cairo_create(item->surface);
 119         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 120         cairo_set_source_rgba(cr, 0, 0, 0, 0);
 121         cairo_paint(cr);
 122
 123         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 124         cairo_translate(cr, item_width / 2, item_height / 2);
 125         t = random();
 126         cairo_move_to(cr, cos(t) * r1, sin(t) * r1);
 127         for (i = 0; i < petal_count; i++, t += dt * 2) {
 128                 x1 = cos(t) * r1;
 129                 y1 = sin(t) * r1;
 130                 x2 = cos(t + dt) * r2;
 131                 y2 = sin(t + dt) * r2;
 132                 x3 = cos(t + 2 * dt) * r1;
 133                 y3 = sin(t + 2 * dt) * r1;
 134
 135                 cairo_curve_to(cr,
 136                                x1 - y1 * u, y1 + x1 * u,
 137                                x2 + y2 * v, y2 - x2 * v,
 138                                x2, y2);
 139
 140                 cairo_curve_to(cr,
 141                                x2 - y2 * v, y2 + x2 * v,
 142                                x3 + y3 * u, y3 - x3 * u,
 143                                x3, y3);
 144         }
 145
 146         cairo_close_path(cr);
 147
 148         cairo_set_source_rgba(cr,
 149                               0.5 + (random() % 50) / 49.0,
 150                               0.5 + (random() % 50) / 49.0,
 151                               0.5 + (random() % 50) / 49.0,
 152                               0.5 + (random() % 100) / 99.0);
 153
 154         cairo_fill_preserve(cr);
 155
 156         cairo_set_line_width(cr, 1);
 157         cairo_set_source_rgba(cr,
 158                               0.5 + (random() % 50) / 49.0,
 159                               0.5 + (random() % 50) / 49.0,
 160                               0.5 + (random() % 50) / 49.0,
 161                               0.5 + (random() % 100) / 99.0);
 162         cairo_stroke(cr);
 163
 164         cairo_destroy(cr);
 165
 166         return item;
 167 }
 168
 169 static void
 170 dnd_draw(struct dnd *dnd)
 171 {
 172         struct rectangle allocation;
 173         cairo_t *cr;
 174         cairo_surface_t *surface;
 175         int i;
 176
 177         window_draw(dnd->window);
 178
 179         surface = window_get_surface(dnd->window);
 180         cr = cairo_create(surface);
 181         window_get_child_allocation(dnd->window, &allocation);
 182         cairo_rectangle(cr, allocation.x, allocation.y,
 183                         allocation.width, allocation.height);
 184         cairo_clip(cr);
 185         cairo_push_group(cr);
 186
 187         cairo_translate(cr, allocation.x, allocation.y);
 188         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 189         cairo_set_source_rgba(cr, 0, 0, 0, 0.8);
 190         cairo_paint(cr);
 191
 192         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 193         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 194                 if (!dnd->items[i])
 195                         continue;
 196                 cairo_set_source_surface(cr, dnd->items[i]->surface,
 197                                          dnd->items[i]->x, dnd->items[i]->y);
 198                 cairo_paint(cr);
 199         }
 200
 201         cairo_pop_group_to_source(cr);
 202         cairo_paint(cr);
 203         cairo_destroy(cr);
 204         cairo_surface_destroy(surface);
 205         window_flush(dnd->window);
 206 }
 207
 208 static void
 209 redraw_handler(struct window *window, void *data)
 210 {
 211         struct dnd *dnd = data;
 212
 213         dnd_draw(dnd);
 214 }
 215
 216 static void
 217 keyboard_focus_handler(struct window *window,
 218                        struct input *device, void *data)
 219 {
 220         struct dnd *dnd = data;
 221
 222         window_schedule_redraw(dnd->window);
 223 }
 224
 225 static void
 226 dnd_offer_destroy(struct dnd_offer *dnd_offer)
 227 {
 228         dnd_offer->refcount--;
 229         if (dnd_offer->refcount == 0) {
 230                 wl_array_release(&dnd_offer->types);
 231                 free(dnd_offer);
 232         }
 233 }
 234
 235 static int
 236 dnd_add_item(struct dnd *dnd, struct item *item)
 237 {
 238         int i;
 239
 240         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 241                 if (dnd->items[i] == 0) {
 242                         dnd->items[i] = item;
 243                         return i;
 244                 }
 245         }
 246         return -1;
 247 }
 248
 249 static struct item *
 250 dnd_get_item(struct dnd *dnd, int32_t x, int32_t y)
 251 {
 252         struct item *item;
 253         struct rectangle allocation;
 254         int i;
 255
 256         window_get_child_allocation(dnd->window, &allocation);
 257
 258         x -= allocation.x;
 259         y -= allocation.y;
 260
 261         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 262                 item = dnd->items[i];
 263                 if (item &&
 264                     item->x <= x && x < item->x + item_width &&
 265                     item->y <= y && y < item->y + item_height)
 266                         return item;
 267         }
 268
 269         return NULL;
 270 }
 271
 272 static void
 273 drag_target(void *data,
 274             struct wl_drag *drag, const char *mime_type)
 275 {
 276         struct dnd_drag *dnd_drag = data;
 277         struct dnd *dnd = dnd_drag->dnd;
 278         struct wl_input_device *device;
 279         cairo_surface_t *surface;
 280         struct wl_buffer *buffer;
 281
 282         fprintf(stderr, "target %s\n", mime_type);
 283         device = input_get_input_device(dnd_drag->input);
 284         dnd_drag->mime_type = mime_type;
 285         if (mime_type)
 286                 surface = dnd_drag->opaque;
 287         else
 288                 surface = dnd_drag->translucent;
 289
 290         buffer = display_get_buffer_for_surface(dnd->display, surface);
 291         wl_input_device_attach(device, dnd_drag->time, buffer,
 292                                dnd_drag->hotspot_x, dnd_drag->hotspot_y);
 293 }
 294
 295 static void
 296 drag_finish(void *data, struct wl_drag *drag, int fd)
 297 {
 298         struct dnd_drag *dnd_drag = data;
 299
 300         if (!dnd_drag->mime_type) {
 301                 dnd_add_item(dnd_drag->dnd, dnd_drag->item);
 302                 window_schedule_redraw(dnd_drag->dnd->window);
 303                 return;
 304         }
 305
 306         struct dnd_flower_message dnd_flower_message;
 307
 308
 309         dnd_flower_message.seed = dnd_drag->item->seed;
 310
 311         dnd_flower_message.x_offset = dnd_drag->x_offset;
 312         dnd_flower_message.y_offset = dnd_drag->y_offset;
 313
 314         fprintf(stderr, "got 'finish', fd %d, sending dnd_flower_message\n", fd);
 315
 316         write(fd, &dnd_flower_message, sizeof dnd_flower_message);
 317         close(fd);
 318
 319         /* The 'finish' event marks the end of the session on the drag
 320          * source side and we need to clean up the drag object created
 321          * and the local state. */
 322         wl_drag_destroy(drag);
 323
 324         /* Destroy the item that has been dragged out */
 325         cairo_surface_destroy(dnd_drag->item->surface);
 326         free(dnd_drag->item);
 327
 328         cairo_surface_destroy(dnd_drag->translucent);
 329         cairo_surface_destroy(dnd_drag->opaque);
 330         free(dnd_drag);
 331 }
 332
 333 static void
 334 drag_reject(void *data, struct wl_drag *drag)
 335 {
 336         struct dnd_drag *dnd_drag = data;
 337
 338         dnd_add_item(dnd_drag->dnd, dnd_drag->item);
 339         window_schedule_redraw(dnd_drag->dnd->window);
 340 }
 341
 342 static const struct wl_drag_listener drag_listener = {
 343         drag_target,
 344         drag_finish,
 345         drag_reject
 346 };
 347
 348 static void
 349 drag_offer_offer(void *data,
 350                  struct wl_drag_offer *offer, const char *type)
 351 {
 352         struct dnd_offer *dnd_offer = data;
 353         char **p;
 354
 355         p = wl_array_add(&dnd_offer->types, sizeof *p);
 356         if (p)
 357                 *p = strdup(type);
 358 }
 359
 360 static void
 361 drag_offer_pointer_focus(void *data,
 362                          struct wl_drag_offer *offer,
 363                          uint32_t time, struct wl_surface *surface,
 364                          int32_t x, int32_t y,
 365                          int32_t surface_x, int32_t surface_y)
 366 {
 367         struct dnd_offer *dnd_offer = data;
 368         struct window *window;
 369         char **p, **end;
 370
 371         /* The last event in a dnd session is pointer_focus with a
 372          * NULL surface, whether or not we get the drop event.  We
 373          * need to clean up the dnd_offer proxy and whatever state we
 374          * allocated. */
 375         if (!surface) {
 376                 fprintf(stderr, "pointer focus NULL, session over\n");
 377                 wl_drag_offer_destroy(offer);
 378                 dnd_offer_destroy(dnd_offer);
 379                 return;
 380         }
 381
 382         fprintf(stderr, "drag pointer focus %p\n", surface);
 383         fprintf(stderr, "offered types:\n");
 384         end = dnd_offer->types.data + dnd_offer->types.size;
 385         for (p = dnd_offer->types.data; p < end; p++)
 386                 fprintf(stderr, "\%s\n", *p);
 387
 388         window = wl_surface_get_user_data(surface);
 389         dnd_offer->dnd = window_get_user_data(window);
 390
 391         if (!dnd_get_item(dnd_offer->dnd, surface_x, surface_y)) {
 392                 wl_drag_offer_accept(offer, time, "application/x-wayland-dnd-flower");
 393                 dnd_offer->drag_type = "application/x-wayland-dnd-flower";
 394                 dnd_offer->x = surface_x;
 395                 dnd_offer->y = surface_y;
 396         } else {
 397                 wl_drag_offer_accept(offer, time, NULL);
 398                 dnd_offer->drag_type = NULL;
 399         }
 400 }
 401
 402 static void
 403 drag_offer_motion(void *data,
 404                   struct wl_drag_offer *offer, uint32_t time,
 405                   int32_t x, int32_t y, int32_t surface_x, int32_t surface_y)
 406 {
 407         struct dnd_offer *dnd_offer = data;
 408
 409         if (!dnd_get_item(dnd_offer->dnd, surface_x, surface_y)) {
 410                 fprintf(stderr, "drag offer motion %d, %d, accepting\n",
 411                         surface_x, surface_y);
 412                 wl_drag_offer_accept(offer, time, "application/x-wayland-dnd-flower");
 413                 dnd_offer->drag_type = "application/x-wayland-dnd-flower";
 414                 dnd_offer->x = surface_x;
 415                 dnd_offer->y = surface_y;
 416         } else {
 417                 fprintf(stderr, "drag offer motion %d, %d, declining\n",
 418                         surface_x, surface_y);
 419                 wl_drag_offer_accept(offer, time, NULL);
 420                 dnd_offer->drag_type = NULL;
 421         }
 422 }
 423
 424 static gboolean
 425 drop_io_func(GIOChannel *source, GIOCondition condition, gpointer data)
 426 {
 427         struct dnd_offer *dnd_offer = data;
 428         struct dnd *dnd = dnd_offer->dnd;
 429         struct dnd_flower_message dnd_flower_message;
 430         int fd;
 431         unsigned int len;
 432         struct item *item;
 433
 434         fd = g_io_channel_unix_get_fd(source);
 435         len = read(fd, &dnd_flower_message, sizeof dnd_flower_message);
 436         fprintf(stderr, "read %d bytes\n", len);
 437
 438         close(fd);
 439         g_source_remove(dnd_offer->tag);
 440
 441         g_io_channel_unref(source);
 442
 443         item = item_create(dnd->display,
 444                            dnd_offer->x - dnd_flower_message.x_offset - 26,
 445                            dnd_offer->y - dnd_flower_message.y_offset - 66,
 446                            dnd_flower_message.seed);
 447
 448         dnd_add_item(dnd, item);
 449         window_schedule_redraw(dnd->window);
 450
 451         dnd_offer_destroy(dnd_offer);
 452
 453         return TRUE;
 454 }
 455
 456 static void
 457 drag_offer_drop(void *data, struct wl_drag_offer *offer)
 458 {
 459         struct dnd_offer *dnd_offer = data;
 460         GIOChannel *channel;
 461         int p[2];
 462
 463         if (!dnd_offer->drag_type) {
 464                 fprintf(stderr, "got 'drop', but no target\n");
 465                 wl_drag_offer_reject(offer);
 466                 return;
 467         }
 468
 469         fprintf(stderr, "got 'drop', sending write end of pipe\n");
 470
 471         dnd_offer->refcount++;
 472         pipe(p);
 473         wl_drag_offer_receive(offer, p[1]);
 474         close(p[1]);
 475
 476         channel = g_io_channel_unix_new(p[0]);
 477         dnd_offer->tag = g_io_add_watch(channel, G_IO_IN,
 478                                         drop_io_func, dnd_offer);
 479 }
 480
 481 static const struct wl_drag_offer_listener drag_offer_listener = {
 482         drag_offer_offer,
 483         drag_offer_pointer_focus,
 484         drag_offer_motion,
 485         drag_offer_drop,
 486 };
 487
 488 static void
 489 global_handler(struct display *display,
 490                const char *interface, uint32_t id, uint32_t version)
 491 {
 492         struct wl_drag_offer *offer;
 493         struct dnd_offer *dnd_offer;
 494
 495         if (strcmp(interface, "drag_offer") != 0)
 496                 return;
 497
 498         offer = wl_drag_offer_create(display_get_display(display), id);
 499
 500         dnd_offer = malloc(sizeof *dnd_offer);
 501         if (dnd_offer == NULL)
 502                 return;
 503
 504         dnd_offer->refcount = 1;
 505
 506         wl_drag_offer_add_listener(offer, &drag_offer_listener, dnd_offer);
 507         wl_array_init(&dnd_offer->types);
 508 }
 509
 510 static cairo_surface_t *
 511 create_drag_cursor(struct dnd_drag *dnd_drag,
 512                    struct item *item, int32_t x, int32_t y, double opacity)
 513 {
 514         struct dnd *dnd = dnd_drag->dnd;
 515         cairo_surface_t *surface, *pointer;
 516         int32_t pointer_width, pointer_height, hotspot_x, hotspot_y;
 517         struct rectangle rectangle;
 518         cairo_pattern_t *pattern;
 519         cairo_t *cr;
 520
 521         pointer = display_get_pointer_surface(dnd->display,
 522                                               POINTER_DRAGGING,
 523                                               &pointer_width,
 524                                               &pointer_height,
 525                                               &hotspot_x,
 526                                               &hotspot_y);
 527
 528         rectangle.width = item_width + 2 * pointer_width;
 529         rectangle.height = item_height + 2 * pointer_height;
 530         surface = display_create_surface(dnd->display, NULL, &rectangle);
 531
 532         cr = cairo_create(surface);
 533         cairo_translate(cr, pointer_width, pointer_height);
 534
 535         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 536         cairo_set_source_rgba(cr, 0, 0, 0, 0);
 537         cairo_paint(cr);
 538
 539         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 540         cairo_set_source_surface(cr, item->surface, 0, 0);
 541         pattern = cairo_pattern_create_rgba(0, 0, 0, opacity);
 542         cairo_mask(cr, pattern);
 543         cairo_pattern_destroy(pattern);
 544
 545         cairo_set_source_surface(cr, pointer,
 546                                  x - item->x - hotspot_x,
 547                                  y - item->y - hotspot_y);
 548         cairo_surface_destroy(pointer);
 549         cairo_paint(cr);
 550         /* FIXME: more cairo-gl brokeness */
 551         display_flush_cairo_device(dnd->display);
 552         cairo_destroy(cr);
 553
 554         dnd_drag->hotspot_x = pointer_width + x - item->x;
 555         dnd_drag->hotspot_y = pointer_height + y - item->y;
 556
 557         return surface;
 558 }
 559
 560 static void
 561 dnd_button_handler(struct window *window,
 562                    struct input *input, uint32_t time,
 563                    int button, int state, void *data)
 564 {
 565         struct dnd *dnd = data;
 566         int32_t x, y;
 567         struct item *item;
 568         struct rectangle allocation;
 569         struct dnd_drag *dnd_drag;
 570         struct wl_drag *drag;
 571         int i;
 572
 573         window_get_child_allocation(dnd->window, &allocation);
 574         input_get_position(input, &x, &y);
 575         item = dnd_get_item(dnd, x, y);
 576         x -= allocation.x;
 577         y -= allocation.y;
 578
 579         if (item && state == 1) {
 580                 fprintf(stderr, "start drag, item %p\n", item);
 581
 582                 dnd_drag = malloc(sizeof *dnd_drag);
 583                 dnd_drag->dnd = dnd;
 584                 dnd_drag->input = input;
 585                 dnd_drag->time = time;
 586                 dnd_drag->item = item;
 587                 dnd_drag->x_offset = x - item->x;
 588                 dnd_drag->y_offset = y - item->y;
 589
 590                 for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 591                         if (item == dnd->items[i]){
 592                                 dnd->items[i] = 0;
 593                                 break;
 594                         }
 595                 }
 596
 597                 dnd_drag->opaque =
 598                         create_drag_cursor(dnd_drag, item, x, y, 1);
 599                 dnd_drag->translucent =
 600                         create_drag_cursor(dnd_drag, item, x, y, 0.2);
 601
 602                 drag = window_create_drag(window);
 603                 wl_drag_offer(drag, "application/x-wayland-dnd-flower");
 604                 window_activate_drag(drag, window, input, time);
 605                 wl_drag_add_listener(drag, &drag_listener, dnd_drag);
 606                 window_schedule_redraw(dnd->window);
 607         }
 608 }
 609
 610 static int
 611 dnd_motion_handler(struct window *window,
 612                    struct input *input, uint32_t time,
 613                    int32_t x, int32_t y,
 614                    int32_t sx, int32_t sy, void *data)
 615 {
 616         struct dnd *dnd = data;
 617         struct item *item;
 618
 619         item = dnd_get_item(dnd, sx, sy);
 620
 621         if (item)
 622                 return POINTER_HAND1;
 623         else
 624                 return POINTER_LEFT_PTR;
 625 }
 626
 627 static struct dnd *
 628 dnd_create(struct display *display)
 629 {
 630         struct dnd *dnd;
 631         int i, x, y;
 632         int32_t width, height;
 633
 634         dnd = malloc(sizeof *dnd);
 635         if (dnd == NULL)
 636                 return dnd;
 637         memset(dnd, 0, sizeof *dnd);
 638
 639         dnd->window = window_create(display, 400, 400);
 640         window_set_title(dnd->window, "Wayland Drag and Drop Demo");
 641
 642         dnd->display = display;
 643         dnd->key = 100;
 644
 645         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 646                 x = (i % 4) * (item_width + item_padding) + item_padding;
 647                 y = (i / 4) * (item_height + item_padding) + item_padding;
 648                 if ((i ^ (i >> 2)) & 1)
 649                         dnd->items[i] = item_create(display, x, y, 0);
 650                 else
 651                         dnd->items[i] = NULL;
 652         }
 653
 654         window_set_user_data(dnd->window, dnd);
 655         window_set_redraw_handler(dnd->window, redraw_handler);
 656         window_set_keyboard_focus_handler(dnd->window,
 657                                           keyboard_focus_handler);
 658         window_set_button_handler(dnd->window,
 659                                   dnd_button_handler);
 660
 661         window_set_motion_handler(dnd->window,
 662                                   dnd_motion_handler);
 663
 664         width = 4 * (item_width + item_padding) + item_padding;
 665         height = 4 * (item_height + item_padding) + item_padding;
 666         window_set_child_size(dnd->window, width, height);
 667
 668         dnd_draw(dnd);
 669
 670         return dnd;
 671 }
 672
 673 static const GOptionEntry option_entries[] = {
 674         { NULL }
 675 };
 676
 677 int
 678 main(int argc, char *argv[])
 679 {
 680         struct display *d;
 681
 682         d = display_create(&argc, &argv, option_entries, global_handler);
 683         if (d == NULL) {
 684                 fprintf(stderr, "failed to create display: %m\n");
 685                 return -1;
 686         }
 687
 688         dnd_create(d);
 689
 690         display_run(d);
 691
 692         return 0;
 693 }