app/main.cpp

   1 #define GST_USE_UNSTABLE_API
   2 #define HAVE_MEMFD_CREATE
   3
   4 #include <string>
   5 #include <iostream>
   6 #include <cstring>
   7 #include <cstdio>
   8 #include <cstdlib>
   9
  10 #include <signal.h>
  11 #include <wayland-client.h>
  12 #include <sys/mman.h>
  13 #include <unistd.h>
  14 #include <fcntl.h>
  15 #include <assert.h>
  16
  17 #include "xdg-shell-client-protocol.h"
  18 #include "agl-shell-desktop-client-protocol.h"
  19 #include "utils.h"
  20
  21 #include <gst/gst.h>
  22
  23 #include <gst/video/videooverlay.h>
  24 #include <gst/wayland/wayland.h>
  25
  26 #if !GST_CHECK_VERSION(1, 22, 0)
  27 #define gst_is_wl_display_handle_need_context_message gst_is_wayland_display_handle_need_context_message
  28 #define gst_wl_display_handle_context_new gst_wayland_display_handle_context_new
  29 #endif
  30
  31 // these only applies if the window is a dialog/pop-up one
  32 // by default the compositor make the window maximized
  33 #define WINDOW_WIDTH_SIZE       640
  34 #define WINDOW_HEIGHT_SIZE      720
  35
  36 #define WINDOW_WIDTH_POS_X      640
  37 #define WINDOW_WIDTH_POS_Y      180
  38
  39 #define MAX_BUFFER_ALLOC        2
  40
  41 // C++ requires a cast and we in wayland we do the cast implictly
  42 #define WL_ARRAY_FOR_EACH(pos, array, type) \
  43         for (pos = (type)(array)->data; \
  44              (const char *) pos < ((const char *) (array)->data + (array)->size); \
  45              (pos)++)
  46
  47 struct display {
  48         struct wl_display *wl_display;
  49         struct wl_registry *wl_registry;
  50         struct wl_compositor *wl_compositor;
  51         struct wl_output *wl_output;
  52         struct wl_shm *shm;
  53
  54         struct {
  55                 int width;
  56                 int height;
  57         } output_data;
  58
  59         struct xdg_wm_base *wm_base;
  60         struct agl_shell_desktop *agl_shell_desktop;
  61
  62         int has_xrgb;
  63 };
  64
  65 struct buffer {
  66         struct wl_buffer *buffer;
  67         void *shm_data;
  68         int busy;
  69         int width, height;
  70         size_t size;    /* width * 4 * height */
  71         struct wl_list buffer_link; /** window::buffer_list */
  72 };
  73
  74 struct window {
  75         struct display *display;
  76
  77         int x, y;
  78         int width, height;
  79         int init_width;
  80         int init_height;
  81
  82         struct wl_surface *surface;
  83
  84         struct xdg_surface *xdg_surface;
  85         struct xdg_toplevel *xdg_toplevel;
  86         bool wait_for_configure;
  87
  88         int fullscreen, maximized;
  89
  90         struct wl_list buffer_list;
  91         struct wl_callback *callback;
  92         bool needs_update_buffer;
  93 };
  94
  95
  96 struct receiver_data {
  97         struct window *window;
  98
  99         GstElement *pipeline;
 100         GstVideoOverlay *overlay;
 101 };
 102
 103 static int running = 1;
 104 static bool gst_pipeline_failed = FALSE;
 105 static bool fallback_gst_pipeline_tried = FALSE;
 106
 107 static void
 108 redraw(void *data, struct wl_callback *callback, uint32_t time);
 109
 110 static struct buffer *
 111 alloc_buffer(struct window *window, int width, int height)
 112 {
 113         struct buffer *buffer = static_cast<struct buffer *>(calloc(1, sizeof(*buffer)));
 114
 115         buffer->width = width;
 116         buffer->height = height;
 117         wl_list_insert(&window->buffer_list, &buffer->buffer_link);
 118
 119         return buffer;
 120 }
 121
 122 static void
 123 destroy_buffer(struct buffer *buffer)
 124 {
 125         if (buffer->buffer)
 126                 wl_buffer_destroy(buffer->buffer);
 127
 128         munmap(buffer->shm_data, buffer->size);
 129         wl_list_remove(&buffer->buffer_link);
 130         free(buffer);
 131 }
 132
 133 static struct buffer *
 134 pick_free_buffer(struct window *window)
 135 {
 136         struct buffer *b;
 137         struct buffer *buffer = NULL;
 138
 139         wl_list_for_each(b, &window->buffer_list, buffer_link) {
 140                 if (!b->busy) {
 141                         buffer = b;
 142                         break;
 143                 }
 144         }
 145
 146         return buffer;
 147 }
 148
 149 static void
 150 prune_old_released_buffers(struct window *window)
 151 {
 152         struct buffer *b, *b_next;
 153
 154         wl_list_for_each_safe(b, b_next,
 155                               &window->buffer_list, buffer_link) {
 156                 if (!b->busy && (b->width != window->width ||
 157                                  b->height != window->height))
 158                         destroy_buffer(b);
 159         }
 160 }
 161
 162 static void
 163 paint_pixels(void *image, int padding, int width, int height, uint32_t time)
 164 {
 165         memset(image, 0x00, width * height * 4);
 166 }
 167
 168 static void
 169 buffer_release(void *data, struct wl_buffer *buffer)
 170 {
 171         struct buffer *mybuf = static_cast<struct buffer *>(data);
 172         mybuf->busy = 0;
 173 }
 174
 175 static const struct wl_buffer_listener buffer_listener = {
 176         buffer_release
 177 };
 178
 179
 180 static int
 181 create_shm_buffer(struct display *display, struct buffer *buffer,
 182                   int width, int height, uint32_t format)
 183 {
 184         struct wl_shm_pool *pool;
 185         int fd, size, stride;
 186         void *data;
 187
 188         stride = width * 4;
 189         size = stride * height;
 190
 191         fd = os_create_anonymous_file(size);
 192         if (fd < 0) {
 193                 fprintf(stderr, "creating a buffer file for %d B failed: %s\n",
 194                                 size, strerror(errno));
 195                 return -1;
 196         }
 197
 198         data = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
 199         if (data == MAP_FAILED) {
 200                 fprintf(stderr, "mmap failed: %s\n", strerror(errno));
 201                 close(fd);
 202                 return -1;
 203         }
 204
 205         pool = wl_shm_create_pool(display->shm, fd, size);
 206         buffer->buffer = wl_shm_pool_create_buffer(pool, 0, width,
 207                                                    height, stride, format);
 208         wl_buffer_add_listener(buffer->buffer, &buffer_listener, buffer);
 209         wl_shm_pool_destroy(pool);
 210         close(fd);
 211
 212         buffer->shm_data = data;
 213         buffer->size = size;
 214         buffer->width = width;
 215         buffer->height = height;
 216
 217         fprintf(stdout, "Created shm buffer with width %d, height %d\n", width, height);
 218         return 0;
 219 }
 220
 221 static struct buffer *
 222 get_next_buffer(struct window *window)
 223 {
 224         struct buffer *buffer = NULL;
 225         int ret = 0;
 226
 227         if (window->needs_update_buffer) {
 228                 int i;
 229
 230                 for (i = 0; i < MAX_BUFFER_ALLOC; i++)
 231                         alloc_buffer(window, window->width, window->height);
 232
 233                 window->needs_update_buffer = false;
 234         }
 235
 236         buffer = pick_free_buffer(window);
 237         if (!buffer)
 238                 return NULL;
 239
 240
 241         if (!buffer->buffer) {
 242                 ret = create_shm_buffer(window->display, buffer, window->width,
 243                                         window->height, WL_SHM_FORMAT_XRGB8888);
 244
 245                 if (ret < 0)
 246                         return NULL;
 247
 248                 /* paint the padding */
 249                 memset(buffer->shm_data, 0x00, window->width * window->height * 4);
 250         }
 251
 252         return buffer;
 253 }
 254
 255
 256 static const struct wl_callback_listener frame_listener = {
 257         redraw
 258 };
 259
 260 static void
 261 redraw(void *data, struct wl_callback *callback, uint32_t time)
 262 {
 263         struct window *window = static_cast<struct window *>(data);
 264         struct buffer *buffer;
 265
 266         prune_old_released_buffers(window);
 267
 268         buffer = get_next_buffer(window);
 269         if (!buffer) {
 270                 fprintf(stderr,
 271                                 !callback ? "Failed to create the first buffer.\n" :
 272                                 "Both buffers busy at redraw(). Server bug?\n");
 273                 abort();
 274         }
 275
 276         // do the actual painting
 277         paint_pixels(buffer->shm_data, 0x0, window->width, window->height, time);
 278
 279         wl_surface_attach(window->surface, buffer->buffer, 0, 0);
 280         wl_surface_damage(window->surface, 0, 0, window->width, window->height);
 281
 282         if (callback)
 283                 wl_callback_destroy(callback);
 284
 285         window->callback = wl_surface_frame(window->surface);
 286         wl_callback_add_listener(window->callback, &frame_listener, window);
 287         wl_surface_commit(window->surface);
 288
 289         buffer->busy = 1;
 290 }
 291
 292 static void
 293 shm_format(void *data, struct wl_shm *wl_shm, uint32_t format)
 294 {
 295         struct display *d = static_cast<struct display *>(data);
 296
 297         if (format == WL_SHM_FORMAT_XRGB8888)
 298                 d->has_xrgb = true;
 299 }
 300
 301 static const struct wl_shm_listener shm_listener = {
 302         shm_format
 303 };
 304
 305 static void
 306 xdg_wm_base_ping(void *data, struct xdg_wm_base *shell, uint32_t serial)
 307 {
 308         xdg_wm_base_pong(shell, serial);
 309 }
 310
 311 static const struct xdg_wm_base_listener xdg_wm_base_listener = {
 312         xdg_wm_base_ping,
 313 };
 314
 315 static void
 316 display_handle_geometry(void *data, struct wl_output *wl_output,
 317                         int x, int y, int physical_width, int physical_height,
 318                         int subpixel, const char *make, const char *model, int transform)
 319 {
 320         (void) data;
 321         (void) wl_output;
 322         (void) x;
 323         (void) y;
 324         (void) physical_width;
 325         (void) physical_height;
 326         (void) subpixel;
 327         (void) make;
 328         (void) model;
 329         (void) transform;
 330 }
 331
 332 static void
 333 display_handle_mode(void *data, struct wl_output *wl_output, uint32_t flags,
 334                     int width, int height, int refresh)
 335 {
 336         struct display *d = static_cast<struct display *>(data);
 337
 338         if (wl_output == d->wl_output && (flags & WL_OUTPUT_MODE_CURRENT)) {
 339                 d->output_data.width = width;
 340                 d->output_data.height = height;
 341
 342                 fprintf(stdout, "Found output with width %d and height %d\n",
 343                                 d->output_data.width, d->output_data.height);
 344         }
 345 }
 346
 347 static void
 348 display_handle_scale(void *data, struct wl_output *wl_output, int scale)
 349 {
 350         (void) data;
 351         (void) wl_output;
 352         (void) scale;
 353 }
 354
 355 static void
 356 display_handle_done(void *data, struct wl_output *wl_output)
 357 {
 358         (void) data;
 359         (void) wl_output;
 360 }
 361
 362 static const struct wl_output_listener output_listener = {
 363         display_handle_geometry,
 364         display_handle_mode,
 365         display_handle_done,
 366         display_handle_scale
 367 };
 368
 369 static void
 370 application_id(void *data, struct agl_shell_desktop *agl_shell_desktop,
 371                 const char *app_id)
 372 {
 373         (void) data;
 374         (void) agl_shell_desktop;
 375         (void) app_id;
 376 }
 377
 378 static void
 379 application_id_state(void *data, struct agl_shell_desktop *agl_shell_desktop,
 380                      const char *app_id, const char *app_data,
 381                      uint32_t app_state, uint32_t app_role)
 382 {
 383         (void) data;
 384         (void) app_data;
 385         (void) agl_shell_desktop;
 386         (void) app_id;
 387         (void) app_state;
 388         (void) app_role;
 389 }
 390
 391 static const struct agl_shell_desktop_listener agl_shell_desktop_listener = {
 392         application_id,
 393         application_id_state,
 394 };
 395
 396 static void
 397 registry_handle_global(void *data, struct wl_registry *registry, uint32_t id,
 398                        const char *interface, uint32_t version)
 399 {
 400         struct display *d = static_cast<struct display *>(data);
 401
 402         if (strcmp(interface, "wl_compositor") == 0) {
 403                 d->wl_compositor =
 404                         static_cast<struct wl_compositor *>(wl_registry_bind(registry, id,
 405                                                     &wl_compositor_interface, 1));
 406         } else if (strcmp(interface, "xdg_wm_base") == 0) {
 407                 d->wm_base = static_cast<struct xdg_wm_base *>(wl_registry_bind(registry,
 408                                 id, &xdg_wm_base_interface, 1));
 409                 xdg_wm_base_add_listener(d->wm_base, &xdg_wm_base_listener, d);
 410         } else if (strcmp(interface, "wl_shm") == 0) {
 411                 d->shm = static_cast<struct wl_shm *>(wl_registry_bind(registry,
 412                                 id, &wl_shm_interface, 1));
 413                 wl_shm_add_listener(d->shm, &shm_listener, d);
 414         } else if (strcmp(interface, "agl_shell_desktop") == 0) {
 415                 d->agl_shell_desktop = static_cast<struct agl_shell_desktop *>(wl_registry_bind(registry, id,
 416                                                         &agl_shell_desktop_interface, 1));
 417                 /* as an example, show how to register for events from the compositor */
 418                 agl_shell_desktop_add_listener(d->agl_shell_desktop,
 419                                                &agl_shell_desktop_listener, d);
 420         } else if (strcmp(interface, "wl_output") == 0) {
 421                 d->wl_output = static_cast<struct wl_output *>(wl_registry_bind(registry, id,
 422                                              &wl_output_interface, 1));
 423                 wl_output_add_listener(d->wl_output, &output_listener, d);
 424         }
 425 }
 426
 427 static void
 428 registry_handle_global_remove(void *data, struct wl_registry *reg, uint32_t id)
 429 {
 430         (void) data;
 431         (void) reg;
 432         (void) id;
 433 }
 434
 435 static const struct wl_registry_listener registry_listener = {
 436         registry_handle_global,
 437         registry_handle_global_remove,
 438 };
 439
 440
 441 static void
 442 error_cb(GstBus *bus, GstMessage *msg, gpointer user_data)
 443 {
 444         struct receiver_data *d =
 445                 static_cast<struct receiver_data *>(user_data);
 446
 447         gchar *debug = NULL;
 448         GError *err = NULL;
 449
 450         gst_message_parse_error(msg, &err, &debug);
 451
 452         g_print("Error: %s\n", err->message);
 453         g_error_free(err);
 454
 455         if (debug) {
 456                 g_print("Debug details: %s\n", debug);
 457                 g_free(debug);
 458         }
 459
 460         gst_element_set_state(d->pipeline, GST_STATE_NULL);
 461 }
 462
 463 static GstBusSyncReply
 464 bus_sync_handler(GstBus *bus, GstMessage *message, gpointer user_data)
 465 {
 466         struct receiver_data *d =
 467                 static_cast<struct receiver_data *>(user_data);
 468
 469         if (gst_is_wl_display_handle_need_context_message(message)) {
 470                 GstContext *context;
 471                 struct wl_display *display_handle = d->window->display->wl_display;
 472
 473                 context = gst_wl_display_handle_context_new(display_handle);
 474                 gst_element_set_context(GST_ELEMENT(GST_MESSAGE_SRC(message)), context);
 475
 476                 goto drop;
 477         } else if (gst_is_video_overlay_prepare_window_handle_message(message)) {
 478                 struct wl_surface *window_handle = d->window->surface;
 479
 480                 /* GST_MESSAGE_SRC(message) will be the overlay object that we
 481                  * have to use. This may be waylandsink, but it may also be
 482                  * playbin. In the latter case, we must make sure to use
 483                  * playbin instead of waylandsink, because playbin resets the
 484                  * window handle and render_rectangle after restarting playback
 485                  * and the actual window size is lost */
 486                 d->overlay = GST_VIDEO_OVERLAY(GST_MESSAGE_SRC(message));
 487
 488                 g_print("setting window handle and size (%d x %d) w %d, h %d\n",
 489                                 d->window->x, d->window->y,
 490                                 d->window->width, d->window->height);
 491
 492                 gst_video_overlay_set_window_handle(d->overlay, (guintptr) window_handle);
 493                 gst_video_overlay_set_render_rectangle(d->overlay,
 494                                                        d->window->x, d->window->y,
 495                                                        d->window->width, d->window->height);
 496
 497                 goto drop;
 498         }
 499         else if (GST_MESSAGE_TYPE(message) == GST_MESSAGE_ERROR) {
 500                 GError* err = NULL;
 501                 gchar* dbg_info = NULL;
 502
 503                 gst_message_parse_error(message, &err, &dbg_info);
 504                 g_printerr("ERROR from element %s: %s code %d\n",
 505                         GST_OBJECT_NAME(message->src), err->message, err->code);
 506                 g_printerr("Debugging info: %s\n", (dbg_info) ? dbg_info : "none");
 507                 gst_pipeline_failed = TRUE;
 508                 g_error_free(err);
 509                 g_free(dbg_info);
 510                 goto drop;
 511         }
 512
 513         return GST_BUS_PASS;
 514
 515 drop:
 516         gst_message_unref(message);
 517         return GST_BUS_DROP;
 518 }
 519
 520 static void
 521 handle_xdg_surface_configure(void *data, struct xdg_surface *surface, uint32_t serial)
 522 {
 523         struct window *window = static_cast<struct window *>(data);
 524
 525         xdg_surface_ack_configure(surface, serial);
 526
 527         if (window->wait_for_configure) {
 528                 redraw(window, NULL, 0);
 529                 window->wait_for_configure = false;
 530         }
 531 }
 532
 533 static const struct xdg_surface_listener xdg_surface_listener = {
 534         handle_xdg_surface_configure,
 535 };
 536
 537 static void
 538 handle_xdg_toplevel_configure(void *data, struct xdg_toplevel *xdg_toplevel,
 539                               int32_t width, int32_t height,
 540                               struct wl_array *states)
 541 {
 542         struct window *window = static_cast<struct window *>(data);
 543         uint32_t *p;
 544
 545         window->fullscreen = 0;
 546         window->maximized = 0;
 547
 548         // use our own macro as C++ can't typecast from (void *) directly
 549         WL_ARRAY_FOR_EACH(p, states, uint32_t *) {
 550                 uint32_t state = *p;
 551                 switch (state) {
 552                 case XDG_TOPLEVEL_STATE_FULLSCREEN:
 553                         window->fullscreen = 1;
 554                         break;
 555                 case XDG_TOPLEVEL_STATE_MAXIMIZED:
 556                         window->maximized = 1;
 557                         break;
 558                 }
 559         }
 560
 561         if (width > 0 && height > 0) {
 562                 if (!window->fullscreen && !window->maximized) {
 563                         window->init_width = width;
 564                         window->init_height = height;
 565                 }
 566                 window->width = width;
 567                 window->height = height;
 568         } else if (!window->fullscreen && !window->maximized) {
 569                 window->width = window->init_width;
 570                 window->height = window->init_height;
 571         }
 572
 573         window->needs_update_buffer = true;
 574
 575 }
 576
 577 static void
 578 handle_xdg_toplevel_close(void *data, struct xdg_toplevel *xdg_toplevel)
 579 {
 580         running = 0;
 581 }
 582
 583 static const struct xdg_toplevel_listener xdg_toplevel_listener = {
 584         handle_xdg_toplevel_configure,
 585         handle_xdg_toplevel_close,
 586 };
 587
 588 static struct window *
 589 create_window(struct display *display, int width, int height, const char *app_id)
 590 {
 591         struct window *window;
 592         int i;
 593
 594         assert(display->wm_base != NULL);
 595
 596         window = static_cast<struct window *>(calloc(1, sizeof(*window)));
 597         if (!window)
 598                 return NULL;
 599
 600         wl_list_init(&window->buffer_list);
 601         window->callback = NULL;
 602         window->display = display;
 603         window->width = width;
 604         window->height = height;
 605         window->surface = wl_compositor_create_surface(display->wl_compositor);
 606
 607         if (display->wm_base) {
 608                 window->xdg_surface =
 609                         xdg_wm_base_get_xdg_surface(display->wm_base, window->surface);
 610                 assert(window->xdg_surface);
 611
 612                 xdg_surface_add_listener(window->xdg_surface,
 613                                          &xdg_surface_listener, window);
 614                 window->xdg_toplevel = xdg_surface_get_toplevel(window->xdg_surface);
 615                 assert(window->xdg_toplevel);
 616
 617                 xdg_toplevel_add_listener(window->xdg_toplevel,
 618                                           &xdg_toplevel_listener, window);
 619
 620                 xdg_toplevel_set_app_id(window->xdg_toplevel, app_id);
 621
 622                 wl_surface_commit(window->surface);
 623                 window->wait_for_configure = true;
 624         }
 625
 626         for (i = 0; i < MAX_BUFFER_ALLOC; i++)
 627                 alloc_buffer(window, window->width, window->height);
 628
 629         return window;
 630 }
 631
 632
 633 static void
 634 destroy_window(struct window *window)
 635 {
 636         struct buffer *buffer, *buffer_next;
 637
 638         if (window->callback)
 639                 wl_callback_destroy(window->callback);
 640
 641         wl_list_for_each_safe(buffer, buffer_next,
 642                               &window->buffer_list, buffer_link)
 643                 destroy_buffer(buffer);
 644
 645         if (window->xdg_toplevel)
 646                 xdg_toplevel_destroy(window->xdg_toplevel);
 647
 648         if (window->xdg_surface)
 649                 xdg_surface_destroy(window->xdg_surface);
 650
 651         wl_surface_destroy(window->surface);
 652         free(window);
 653 }
 654
 655 static void
 656 signal_int(int sig, siginfo_t *si, void *_unused)
 657 {
 658         running = 0;
 659 }
 660
 661 static struct display *
 662 create_display(int argc, char *argv[])
 663 {
 664         struct display *display;
 665
 666         display = static_cast<struct display *>(calloc(1, sizeof(*display)));
 667         if (display == NULL) {
 668                 fprintf(stderr, "out of memory\n");
 669                 exit(1);
 670         }
 671         display->wl_display = wl_display_connect(NULL);
 672         assert(display->wl_display);
 673
 674         display->has_xrgb = false;
 675         display->wl_registry = wl_display_get_registry(display->wl_display);
 676
 677         wl_registry_add_listener(display->wl_registry, &registry_listener, display);
 678         wl_display_roundtrip(display->wl_display);
 679
 680         if (display->shm == NULL) {
 681                 fprintf(stderr, "No wl_shm global\n");
 682                 return NULL;
 683         }
 684
 685         if (display->agl_shell_desktop == NULL) {
 686                 fprintf(stderr, "No agl_shell extension present\n");
 687                 return NULL;
 688         }
 689
 690         wl_display_roundtrip(display->wl_display);
 691
 692         if (!display->has_xrgb) {
 693                 fprintf(stderr, "WL_SHM_FORMAT_XRGB32 not available\n");
 694                 return NULL;
 695         }
 696
 697         return display;
 698 }
 699
 700 static void
 701 destroy_display(struct display *display)
 702 {
 703         if (display->shm)
 704                 wl_shm_destroy(display->shm);
 705
 706         if (display->wm_base)
 707                 xdg_wm_base_destroy(display->wm_base);
 708
 709         if (display->agl_shell_desktop)
 710                 agl_shell_desktop_destroy(display->agl_shell_desktop);
 711
 712         if (display->wl_compositor)
 713                 wl_compositor_destroy(display->wl_compositor);
 714
 715         wl_registry_destroy(display->wl_registry);
 716         wl_display_flush(display->wl_display);
 717         wl_display_disconnect(display->wl_display);
 718         free(display);
 719 }
 720
 721 // stringify the un-quoted string to quoted C string
 722 #define xstr(a) str(a)
 723 #define str(a) #a
 724
 725 GstElement* create_pipeline(int* argc, char** argv[])
 726 {
 727         GError *error = NULL;
 728         const char *camera_device = NULL;
 729         const char *width_str = NULL;
 730         const char *height_str = NULL;
 731         int width;
 732         int height;
 733
 734         // pipewire is default.
 735         char *v4l2_path = getenv("ENABLE_V4L2_PATH");
 736         bool v4l2 = false;
 737
 738         char pipeline_str[1024];
 739
 740         camera_device = getenv("DEFAULT_V4L2_DEVICE");
 741         if (!camera_device)
 742                 camera_device = get_first_camera_device();
 743
 744         width_str = getenv("DEFAULT_DEVICE_WIDTH");
 745         if (!width_str)
 746                 width = WINDOW_WIDTH_SIZE;
 747         else
 748                 width = atoi(width_str);
 749
 750         height_str = getenv("DEFAULT_DEVICE_HEIGHT");
 751         if (!height_str)
 752                 height = WINDOW_HEIGHT_SIZE;
 753         else
 754                 height = atoi(height_str);
 755
 756         if (v4l2_path == NULL)
 757                 v4l2 = false;
 758         else if (g_str_equal(v4l2_path, "yes") || g_str_equal(v4l2_path, "true"))
 759                 v4l2 = true;
 760
 761         memset(pipeline_str, 0, sizeof(pipeline_str));
 762
 763         if (v4l2)
 764                 snprintf(pipeline_str, sizeof(pipeline_str), "v4l2src device=%s ! video/x-raw,width=%d,height=%d ! waylandsink",
 765                         camera_device, width, height);
 766         else if (gst_pipeline_failed == TRUE) {
 767                 snprintf(pipeline_str, sizeof(pipeline_str), "filesrc location=%s/still-image.jpg ! decodebin ! videoconvert ! imagefreeze ! waylandsink fullscreen=true",
 768                         xstr(APP_DATA_PATH), width, height);
 769                 fallback_gst_pipeline_tried = TRUE;
 770         }
 771         else {
 772                 snprintf(pipeline_str, sizeof(pipeline_str), "pipewiresrc ! video/x-raw,width=%d,height=%d ! waylandsink", width,
 773                         height);
 774         }
 775
 776         fprintf(stdout, "Using pipeline: %s\n", pipeline_str);
 777
 778         GstElement *pipeline = gst_parse_launch(pipeline_str, &error);
 779
 780         if (error || !pipeline) {
 781                 fprintf(stderr, "gstreamer pipeline construction failed!\n");
 782                 free(argv);
 783                 return NULL;
 784         }
 785
 786         return pipeline;
 787 }
 788
 789 int main(int argc, char* argv[])
 790 {
 791         int ret = 0;
 792         struct sigaction sa;
 793         struct receiver_data receiver_data = {};
 794         struct display* display;
 795         struct window* window;
 796         const char* app_id = "camera-gstreamer";
 797
 798         sa.sa_sigaction = signal_int;
 799         sigemptyset(&sa.sa_mask);
 800         sa.sa_flags = SA_RESETHAND | SA_SIGINFO;
 801         sigaction(SIGINT, &sa, NULL);
 802
 803         int gargc = 2;
 804         char** gargv = static_cast<char**>(calloc(2, sizeof(char*)));
 805
 806         gargv[0] = strdup(argv[0]);
 807         gargv[1] = strdup("--gst-debug-level=2");
 808
 809         setbuf(stdout, NULL);
 810
 811         gst_init(&gargc, &gargv);
 812
 813         receiver_data.pipeline = create_pipeline(&gargc, &gargv);
 814
 815         if (!receiver_data.pipeline)
 816                 return EXIT_FAILURE;
 817
 818         display = create_display(argc, argv);
 819         if (!display)
 820                 return -1;
 821
 822         // if you'd want to place the video in a pop-up/dialog type of window:
 823         // agl_shell_desktop_set_app_property(display->agl_shell_desktop, app_id,
 824         //                                 AGL_SHELL_DESKTOP_APP_ROLE_POPUP,
 825         //                                 WINDOW_WIDTH_POS_X, WINDOW_WIDTH_POS_Y,
 826         //                                 0, 0, WINDOW_WIDTH_SIZE, WINDOW_HEIGHT_SIZE,
 827         //                                 display->wl_output);
 828
 829         // we use the role to set a correspondence between the top level
 830         // surface and our application, with the previous call letting the
 831         // compositor know that we're one and the same
 832         window = create_window(display, WINDOW_WIDTH_SIZE, WINDOW_HEIGHT_SIZE, app_id);
 833
 834         if (!window) {
 835                 free(gargv);
 836                 return EXIT_FAILURE;
 837         }
 838
 839         window->display = display;
 840         receiver_data.window = window;
 841
 842         /* Initialise damage to full surface, so the padding gets painted */
 843         wl_surface_damage(window->surface, 0, 0,
 844                           window->width, window->height);
 845
 846         if (!window->wait_for_configure) {
 847                 redraw(window, NULL, 0);
 848         }
 849
 850         GstBus *bus = gst_element_get_bus(receiver_data.pipeline);
 851         gst_bus_add_signal_watch(bus);
 852
 853         g_signal_connect(bus, "message::error", G_CALLBACK(error_cb), &receiver_data);
 854         gst_bus_set_sync_handler(bus, bus_sync_handler, &receiver_data, NULL);
 855         gst_object_unref(bus);
 856
 857         gst_element_set_state(receiver_data.pipeline, GST_STATE_PLAYING);
 858         fprintf(stdout, "gstreamer pipeline running\n");
 859
 860         // run the application
 861         while (running && ret != -1) {
 862                 ret = wl_display_dispatch(display->wl_display);
 863                 if (gst_pipeline_failed && fallback_gst_pipeline_tried == FALSE) {
 864                         gst_element_set_state(receiver_data.pipeline, GST_STATE_NULL);
 865                         gst_object_unref(receiver_data.pipeline);
 866                         /* retry with fallback pipeline */
 867                         receiver_data.pipeline = create_pipeline(&gargc, &gargv);
 868                         GstBus *bus = gst_element_get_bus(receiver_data.pipeline);
 869                         gst_bus_add_signal_watch(bus);
 870                         g_signal_connect(bus, "message::error", G_CALLBACK(error_cb), &receiver_data);
 871                         gst_bus_set_sync_handler(bus, bus_sync_handler, &receiver_data, NULL);
 872                         gst_object_unref(bus);
 873                         gst_element_set_state(receiver_data.pipeline, GST_STATE_PLAYING);
 874                 }
 875         }
 876         gst_element_set_state(receiver_data.pipeline, GST_STATE_NULL);
 877         gst_object_unref(receiver_data.pipeline);
 878
 879         destroy_window(window);
 880         destroy_display(display);
 881         free(gargv);
 882
 883         return ret;
 884 }