Initial import of receiver source code

11 files changed, 1792 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..4e2021d
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+*.o
+.clang-format
+compile_commands.json
+compile_flags.txt
+receiver
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..f288702
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
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+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<https://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<https://www.gnu.org/licenses/why-not-lgpl.html>.
diff --git a/decode.c b/decode.c
new file mode 100644
index 0000000..f51fd83
--- /dev/null
+++ b/decode.c
@@ -0,0 +1,419 @@
+/*
+ * Copyright (C) 2023 Mikhail Burakov. This file is part of receiver.
+ *
+ * receiver is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * receiver is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with receiver.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "decode.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <mfxvideo.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <va/va.h>
+#include <va/va_drm.h>
+#include <va/va_drmcommon.h>
+
+#include "frame.h"
+#include "util.h"
+
+struct Surface {
+  VASurfaceID surface_id;
+  mfxFrameInfo frame_info;
+  struct Frame* frame;
+  bool locked;
+};
+
+struct DecodeContext {
+  int drm_fd;
+  VADisplay display;
+  mfxSession session;
+  mfxFrameAllocator allocator;
+  bool initialized;
+
+  uint32_t packet_size;
+  uint8_t* packet_data;
+  uint32_t packet_alloc;
+  uint32_t packet_offset;
+  struct Surface** sufaces;
+  struct Frame* decoded;
+};
+
+static void SurfaceDestroy(struct Surface*** psurfaces) {
+  if (!psurfaces || !*psurfaces) return;
+  for (struct Surface** surfaces = *psurfaces; *surfaces; surfaces++) {
+    if ((*surfaces)->frame) FrameDestroy(&(*surfaces)->frame);
+    free(*surfaces);
+  }
+  free(*psurfaces);
+  *psurfaces = NULL;
+}
+
+static struct Frame* ExportFrame(VADisplay display, VASurfaceID surface_id) {
+  VADRMPRIMESurfaceDescriptor prime;
+  VAStatus status = vaExportSurfaceHandle(
+      display, surface_id, VA_SURFACE_ATTRIB_MEM_TYPE_DRM_PRIME_2,
+      VA_EXPORT_SURFACE_WRITE_ONLY | VA_EXPORT_SURFACE_COMPOSED_LAYERS, &prime);
+  if (status != VA_STATUS_SUCCESS) {
+    LOG("Failed to export vaapi surface (%d)", status);
+    return NULL;
+  }
+
+  struct FramePlane planes[prime.layers[0].num_planes];
+  for (size_t i = 0; i < LENGTH(planes); i++) {
+    planes[i] = (struct FramePlane){
+        .dmabuf_fd = prime.objects[prime.layers[0].object_index[i]].fd,
+        .pitch = prime.layers[0].pitch[i],
+        .offset = prime.layers[0].offset[i],
+        .modifier =
+            prime.objects[prime.layers[0].object_index[i]].drm_format_modifier,
+    };
+  }
+
+  struct Frame* frame = FrameCreate(prime.width, prime.height, prime.fourcc,
+                                    prime.layers[0].num_planes, planes);
+  if (!frame) LOG("Failed to create frame");
+  for (size_t i = prime.num_objects; i; i--) close(prime.objects[i - 1].fd);
+  return frame;
+}
+
+static mfxStatus OnAllocatorAlloc(mfxHDL pthis, mfxFrameAllocRequest* request,
+                                  mfxFrameAllocResponse* response) {
+  LOG("%s(AllocId=%u, NumFrameSuggested=%u)", __func__, request->AllocId,
+      request->NumFrameSuggested);
+  if (request->Info.FourCC != MFX_FOURCC_NV12) {
+    LOG("Allocation of %.4s surfaces is not supported",
+        (const char*)&request->Info.FourCC);
+    return MFX_ERR_UNSUPPORTED;
+  }
+  if (request->Info.ChromaFormat != MFX_CHROMAFORMAT_YUV420) {
+    LOG("Chroma format %u is not supported", request->Info.ChromaFormat);
+    return MFX_ERR_UNSUPPORTED;
+  }
+
+  struct AUTO(Surface)** surfaces =
+      calloc(request->NumFrameSuggested + 1, sizeof(struct Surface*));
+  if (!surfaces) {
+    LOG("Failed to allocate surfaces storage (%s)", strerror(errno));
+    return MFX_ERR_MEMORY_ALLOC;
+  }
+  for (size_t i = 0; i < request->NumFrameSuggested; i++) {
+    surfaces[i] = calloc(1, sizeof(struct Surface));
+    if (!surfaces[i]) {
+      LOG("Failed to allocate surface (%s)", strerror(errno));
+      return MFX_ERR_MEMORY_ALLOC;
+    }
+  }
+
+  VASurfaceID surface_ids[request->NumFrameSuggested];
+  struct DecodeContext* decode_context = pthis;
+  VASurfaceAttrib attrib_list[] = {
+      {.type = VASurfaceAttribPixelFormat,
+       .value.type = VAGenericValueTypeInteger,
+       .value.value.i = VA_FOURCC_NV12},
+      {.type = VASurfaceAttribUsageHint,
+       .value.type = VAGenericValueTypeInteger,
+       .value.value.i = VA_SURFACE_ATTRIB_USAGE_HINT_DECODER |
+                        VA_SURFACE_ATTRIB_USAGE_HINT_EXPORT},
+  };
+  VAStatus status = vaCreateSurfaces(
+      decode_context->display, VA_RT_FORMAT_YUV420, request->Info.Width,
+      request->Info.Height, surface_ids, request->NumFrameSuggested,
+      attrib_list, LENGTH(attrib_list));
+  if (status != VA_STATUS_SUCCESS) {
+    LOG("Failed to allocate surfaces (%d)", status);
+    return MFX_ERR_MEMORY_ALLOC;
+  }
+
+  for (size_t i = 0; i < request->NumFrameSuggested; i++) {
+    surfaces[i]->surface_id = surface_ids[i];
+    surfaces[i]->frame_info = request->Info;
+  }
+
+  // mburakov: Separate loop for frames to ensure proper cleanup in destructor.
+  for (size_t i = 0; i < request->NumFrameSuggested; i++) {
+    surfaces[i]->frame =
+        ExportFrame(decode_context->display, surfaces[i]->surface_id);
+    if (!surfaces[i]->frame) {
+      LOG("Failed to export frame");
+      return MFX_ERR_MEMORY_ALLOC;
+    }
+  }
+
+  decode_context->sufaces = RELEASE(surfaces);
+  *response = (mfxFrameAllocResponse){
+      .AllocId = request->AllocId,
+      .mids = (void**)decode_context->sufaces,
+      .NumFrameActual = request->NumFrameSuggested,
+  };
+  return MFX_ERR_NONE;
+}
+
+static mfxStatus OnAllocatorGetHDL(mfxHDL pthis, mfxMemId mid, mfxHDL* handle) {
+  (void)pthis;
+  struct Surface* surface = mid;
+  *handle = &surface->surface_id;
+  return MFX_ERR_NONE;
+}
+
+static mfxStatus OnAllocatorFree(mfxHDL pthis,
+                                 mfxFrameAllocResponse* response) {
+  LOG("%s(AllocId=%u)", __func__, response->AllocId);
+  VASurfaceID surface_ids[response->NumFrameActual];
+  struct Surface** surfaces = (struct Surface**)response->mids;
+  for (size_t i = 0; i < response->NumFrameActual; i++)
+    surface_ids[i] = surfaces[i]->surface_id;
+  struct DecodeContext* decode_context = pthis;
+  vaDestroySurfaces(decode_context->display, surface_ids,
+                    response->NumFrameActual);
+  SurfaceDestroy(&decode_context->sufaces);
+  return MFX_ERR_NONE;
+}
+
+struct DecodeContext* DecodeContextCreate(void) {
+  struct AUTO(DecodeContext)* decode_context =
+      malloc(sizeof(struct DecodeContext));
+  if (!decode_context) {
+    LOG("Failed to allocate decode context (%s)", strerror(errno));
+    return NULL;
+  }
+  *decode_context = (struct DecodeContext){
+      .drm_fd = -1,
+      .allocator.pthis = decode_context,
+      .allocator.Alloc = OnAllocatorAlloc,
+      .allocator.GetHDL = OnAllocatorGetHDL,
+      .allocator.Free = OnAllocatorFree,
+  };
+
+  decode_context->drm_fd = open("/dev/dri/renderD128", O_RDWR);
+  if (decode_context->drm_fd == -1) {
+    LOG("Failed to open render node (%s)", strerror(errno));
+    return NULL;
+  }
+
+  decode_context->display = vaGetDisplayDRM(decode_context->drm_fd);
+  if (!decode_context->display) {
+    LOG("Failed to get vaapi display (%s)", strerror(errno));
+    return NULL;
+  }
+  int major, minor;
+  VAStatus st = vaInitialize(decode_context->display, &major, &minor);
+  if (st != VA_STATUS_SUCCESS) {
+    LOG("Failed to init vaapi (%d)", st);
+    return NULL;
+  }
+
+  LOG("Initialized vaapi %d.%d", major, minor);
+  mfxStatus status = MFXInit(MFX_IMPL_HARDWARE, NULL, &decode_context->session);
+  if (status != MFX_ERR_NONE) {
+    LOG("Failed to init mfx session (%d)", status);
+    return NULL;
+  }
+  status = MFXVideoCORE_SetHandle(
+      decode_context->session, MFX_HANDLE_VA_DISPLAY, decode_context->display);
+  if (status != MFX_ERR_NONE) {
+    LOG("Failed to set mfx session display (%d)", status);
+    return NULL;
+  }
+  status = MFXVideoCORE_SetFrameAllocator(decode_context->session,
+                                          &decode_context->allocator);
+  if (status != MFX_ERR_NONE) {
+    LOG("Failed to set frame allocator (%d)", status);
+    return NULL;
+  }
+  return RELEASE(decode_context);
+}
+
+static bool InitializeDecoder(struct DecodeContext* decode_context,
+                              mfxBitstream* bitstream) {
+  mfxVideoParam video_param = {
+      .mfx.CodecId = MFX_CODEC_AVC,
+  };
+  mfxStatus status = MFXVideoDECODE_DecodeHeader(decode_context->session,
+                                                 bitstream, &video_param);
+  switch (status) {
+    case MFX_ERR_NONE:
+      break;
+    case MFX_ERR_MORE_DATA:
+      return true;
+    default:
+      LOG("Failed to parse decode header (%d)", status);
+      return false;
+  }
+
+  video_param.AsyncDepth = 1;
+  video_param.mfx.DecodedOrder = 1;
+  video_param.IOPattern = MFX_IOPATTERN_OUT_VIDEO_MEMORY;
+  status =
+      MFXVideoDECODE_Query(decode_context->session, &video_param, &video_param);
+  if (status != MFX_ERR_NONE) {
+    LOG("Failed to query decode (%d)", status);
+    return false;
+  }
+
+  status = MFXVideoDECODE_Init(decode_context->session, &video_param);
+  if (status != MFX_ERR_NONE) {
+    LOG("Failed to init decode (%d)", status);
+    return false;
+  }
+  decode_context->initialized = true;
+  return true;
+}
+
+static bool ReadSomePacketData(struct DecodeContext* decode_context, int fd) {
+again:;
+  void* target;
+  size_t size;
+  if (!decode_context->packet_size) {
+    target = &decode_context->packet_size;
+    size = sizeof(decode_context->packet_size);
+  } else {
+    target = decode_context->packet_data + decode_context->packet_offset;
+    size = decode_context->packet_size - decode_context->packet_offset;
+  }
+  ssize_t result = read(fd, target, size);
+  switch (result) {
+    case -1:
+      if (errno == EINTR) goto again;
+      LOG("Failed to read packet data (%s)", strerror(errno));
+      return false;
+    case 0:
+      LOG("File descriptor was closed");
+      return false;
+    default:
+      break;
+  }
+  if (target != &decode_context->packet_size) {
+    decode_context->packet_offset += result;
+    return true;
+  }
+  if (result != (ssize_t)size) {
+    LOG("Failed to read complete packet size");
+    return false;
+  }
+  if (decode_context->packet_size > decode_context->packet_alloc) {
+    uint32_t packet_alloc = decode_context->packet_size;
+    uint8_t* packet_data = malloc(packet_alloc);
+    if (!packet_data) {
+      LOG("Failed to reallocate packet data (%s)", strerror(errno));
+      return false;
+    }
+    free(decode_context->packet_data);
+    decode_context->packet_data = packet_data;
+    decode_context->packet_alloc = packet_alloc;
+  }
+  return true;
+}
+
+static struct Surface* GetFreeSurface(struct DecodeContext* decode_context) {
+  struct Surface** psurface = decode_context->sufaces;
+  for (; *psurface && (*psurface)->locked; psurface++)
+    ;
+  (*psurface)->locked = true;
+  return *psurface;
+}
+
+static void UnlockAllSurfaces(struct DecodeContext* decode_context,
+                              const struct Surface* keep_locked) {
+  struct Surface** psurface = decode_context->sufaces;
+  for (; *psurface; psurface++) {
+    if (*psurface != keep_locked) (*psurface)->locked = false;
+  }
+}
+
+bool DecodeContextDecode(struct DecodeContext* decode_context, int fd) {
+  if (!ReadSomePacketData(decode_context, fd)) {
+    LOG("Failed to read some packet data");
+    return false;
+  }
+
+  if (decode_context->packet_size != decode_context->packet_offset) {
+    // mburakov: Full frame has to be available for decoding.
+    return true;
+  }
+  mfxBitstream bitstream = {
+      .DecodeTimeStamp = MFX_TIMESTAMP_UNKNOWN,
+      .TimeStamp = (mfxU64)MFX_TIMESTAMP_UNKNOWN,
+      .Data = decode_context->packet_data,
+      .DataLength = decode_context->packet_size,
+      .MaxLength = decode_context->packet_size,
+      .DataFlag = MFX_BITSTREAM_COMPLETE_FRAME,
+  };
+  decode_context->packet_size = 0;
+  decode_context->packet_offset = 0;
+
+  if (!decode_context->initialized) {
+    if (!InitializeDecoder(decode_context, &bitstream)) {
+      LOG("Failed to initialize decoder");
+      return false;
+    }
+    // mburakov: Initialization might be postponed.
+    if (!decode_context->initialized) return true;
+  }
+
+  for (;;) {
+    struct Surface* surface = GetFreeSurface(decode_context);
+    mfxFrameSurface1 surface_work = {
+        .Info = surface->frame_info,
+        .Data.MemId = surface,
+    };
+    mfxFrameSurface1* surface_out = NULL;
+    mfxSyncPoint sync = NULL;
+    mfxStatus status =
+        MFXVideoDECODE_DecodeFrameAsync(decode_context->session, &bitstream,
+                                        &surface_work, &surface_out, &sync);
+    switch (status) {
+      case MFX_ERR_MORE_SURFACE:
+        continue;
+      case MFX_ERR_NONE:
+        break;
+      case MFX_WRN_VIDEO_PARAM_CHANGED:
+        continue;
+      default:
+        LOG("Failed to decode frame (%d)", status);
+        return false;
+    }
+
+    status =
+        MFXVideoCORE_SyncOperation(decode_context->session, sync, MFX_INFINITE);
+    if (status != MFX_ERR_NONE) {
+      LOG("Failed to sync operation (%d)", status);
+      return false;
+    }
+
+    surface = surface_out->Data.MemId;
+    decode_context->decoded = surface->frame;
+    UnlockAllSurfaces(decode_context, surface);
+    return true;
+  }
+}
+
+const struct Frame* DecodeContextGetFrame(
+    struct DecodeContext* decode_context) {
+  return decode_context->decoded;
+}
+
+void DecodeContextDestroy(struct DecodeContext** decode_context) {
+  if (!decode_context || !*decode_context) return;
+  if ((*decode_context)->packet_data) free((*decode_context)->packet_data);
+  if ((*decode_context)->session) MFXClose((*decode_context)->session);
+  if ((*decode_context)->display) vaTerminate((*decode_context)->display);
+  if ((*decode_context)->drm_fd) close((*decode_context)->drm_fd);
+  free(*decode_context);
+  *decode_context = NULL;
+}
diff --git a/decode.h b/decode.h
new file mode 100644
index 0000000..6926091
--- /dev/null
+++ b/decode.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2023 Mikhail Burakov. This file is part of receiver.
+ *
+ * receiver is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * receiver is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with receiver.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef RECEIVER_DECODE_H_
+#define RECEIVER_DECODE_H_
+
+#include <stdbool.h>
+#include <stddef.h>
+
+struct DecodeContext;
+struct Frame;
+
+struct DecodeContext* DecodeContextCreate(void);
+bool DecodeContextDecode(struct DecodeContext* decode_context, int fd);
+const struct Frame* DecodeContextGetFrame(struct DecodeContext* decode_context);
+void DecodeContextDestroy(struct DecodeContext** decode_context);
+
+#endif  // RECEIVER_DECODE_H_
diff --git a/frame.c b/frame.c
new file mode 100644
index 0000000..2e008ed
--- /dev/null
+++ b/frame.c
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2023 Mikhail Burakov. This file is part of receiver.
+ *
+ * receiver is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * receiver is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with receiver.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "frame.h"
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "util.h"
+
+struct Frame* FrameCreate(uint32_t width, uint32_t height, uint32_t fourcc,
+                          size_t nplanes, const struct FramePlane* planes) {
+  struct AUTO(Frame)* frame = malloc(sizeof(struct Frame));
+  if (!frame) {
+    LOG("Failed to allocate frame (%s)", strerror(errno));
+    return NULL;
+  }
+  *frame = (struct Frame){
+      .width = width,
+      .height = height,
+      .fourcc = fourcc,
+      .nplanes = nplanes,
+      .planes[0] = {.dmabuf_fd = -1, .pitch = 0, .offset = 0, .modifier = 0},
+      .planes[1] = {.dmabuf_fd = -1, .pitch = 0, .offset = 0, .modifier = 0},
+      .planes[2] = {.dmabuf_fd = -1, .pitch = 0, .offset = 0, .modifier = 0},
+      .planes[3] = {.dmabuf_fd = -1, .pitch = 0, .offset = 0, .modifier = 0},
+  };
+
+  for (size_t i = 0; i < nplanes; i++) {
+    frame->planes[i] = (struct FramePlane){
+        .dmabuf_fd = dup(planes[i].dmabuf_fd),
+        .pitch = planes[i].pitch,
+        .offset = planes[i].offset,
+        .modifier = planes[i].modifier,
+    };
+    if (frame->planes[i].dmabuf_fd == -1) {
+      LOG("Failed to dup dmabuf fd (%s)", strerror(errno));
+      return NULL;
+    }
+  }
+
+  return RELEASE(frame);
+}
+
+void FrameDestroy(struct Frame** frame) {
+  if (!frame || !*frame) return;
+  for (size_t i = (*frame)->nplanes; i; i--) {
+    if ((*frame)->planes[i].dmabuf_fd != -1)
+      close((*frame)->planes[i].dmabuf_fd);
+  }
+}
diff --git a/frame.h b/frame.h
new file mode 100644
index 0000000..597b0f3
--- /dev/null
+++ b/frame.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2023 Mikhail Burakov. This file is part of receiver.
+ *
+ * receiver is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * receiver is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with receiver.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef RECEIVER_FRAME_H_
+#define RECEIVER_FRAME_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+struct FramePlane {
+  int dmabuf_fd;
+  uint32_t pitch;
+  uint32_t offset;
+  uint64_t modifier;
+};
+
+struct Frame {
+  uint32_t width;
+  uint32_t height;
+  uint32_t fourcc;
+  size_t nplanes;
+  struct FramePlane planes[4];
+};
+
+struct Frame* FrameCreate(uint32_t width, uint32_t height, uint32_t fourcc,
+                          size_t nplanes, const struct FramePlane* planes);
+void FrameDestroy(struct Frame** frame);
+
+#endif  // RECEIVER_FRAME_H_
diff --git a/main.c b/main.c
new file mode 100644
index 0000000..fcc7511
--- /dev/null
+++ b/main.c
@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2023 Mikhail Burakov. This file is part of receiver.
+ *
+ * receiver is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * receiver is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with receiver.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <errno.h>
+#include <poll.h>
+#include <signal.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "decode.h"
+#include "util.h"
+#include "window.h"
+
+static volatile sig_atomic_t g_signal;
+static void OnSignal(int status) { g_signal = status; }
+
+int main(int argc, char* argv[]) {
+  (void)argc;
+  (void)argv;
+
+  struct AUTO(DecodeContext)* decode_context = DecodeContextCreate();
+  if (!decode_context) {
+    LOG("Failed to create decode context");
+    return EXIT_FAILURE;
+  }
+
+  struct AUTO(Window)* window = WindowCreate();
+  if (!window) {
+    LOG("Failed to create window");
+    return EXIT_FAILURE;
+  }
+
+  int events_fd = WindowGetEventsFd(window);
+  if (events_fd == -1) {
+    LOG("Failed to get events fd");
+    return EXIT_FAILURE;
+  }
+
+  if (signal(SIGINT, OnSignal) == SIG_ERR ||
+      signal(SIGTERM, OnSignal) == SIG_ERR) {
+    LOG("Failed to set signal handlers (%s)", strerror(errno));
+    return EXIT_FAILURE;
+  }
+
+  while (!g_signal) {
+    struct pollfd pfds[] = {
+        {.fd = STDIN_FILENO, .events = POLLIN},
+        {.fd = events_fd, .events = POLLIN},
+    };
+    switch (poll(pfds, LENGTH(pfds), -1)) {
+      case -1:
+        if (errno != EINTR) {
+          LOG("Failed to poll (%s)", strerror(errno));
+          return EXIT_FAILURE;
+        }
+        __attribute__((fallthrough));
+      case 0:
+        continue;
+      default:
+        break;
+    }
+    if (pfds[0].revents && !DecodeContextDecode(decode_context, STDIN_FILENO)) {
+      LOG("Failed to decode incoming data");
+      return EXIT_FAILURE;
+    }
+    if (pfds[1].revents && !WindowProcessEvents(window)) {
+      LOG("Failed to process window events");
+      return EXIT_FAILURE;
+    }
+    const struct Frame* frame = DecodeContextGetFrame(decode_context);
+    if (frame && !WindowRenderFrame(window, frame)) {
+      LOG("Failed to render frame");
+      return EXIT_FAILURE;
+    }
+  }
+
+  return EXIT_SUCCESS;
+}
diff --git a/makefile b/makefile
new file mode 100644
index 0000000..24bc614
--- /dev/null
+++ b/makefile
@@ -0,0 +1,42 @@
+bin:=$(notdir $(shell pwd))
+src:=$(wildcard *.c)
+obj:=$(src:.c=.o)
+
+libs:=\
+	libva \
+	libva-drm \
+	mfx \
+	wayland-client
+
+protocols_dir:=\
+	/usr/share/wayland-protocols
+
+protocols:=\
+	linux-dmabuf-unstable-v1 \
+	xdg-shell
+
+obj:=$(patsubst %,%.o,$(protocols)) $(obj)
+headers:=$(patsubst %,%.h,$(protocols))
+CFLAGS+=$(shell pkg-config --cflags $(libs))
+LDFLAGS+=$(shell pkg-config --libs $(libs))
+
+all: $(bin)
+
+$(bin): $(obj)
+	$(CC) $^ $(LDFLAGS) -o $@
+
+%.o: %.c *.h $(headers)
+	$(CC) -c $< $(CFLAGS) -o $@
+
+%.h: $(protocols_dir)/*/*/%.xml
+	wayland-scanner client-header $< $@
+
+%.c: $(protocols_dir)/*/*/%.xml
+	wayland-scanner private-code $< $@
+
+clean:
+	-rm $(bin) $(obj) $(headers)
+
+.PHONY: all clean
+
+.PRECIOUS: $(headers)
diff --git a/util.h b/util.h
new file mode 100644
index 0000000..bbc858f
--- /dev/null
+++ b/util.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2023 Mikhail Burakov. This file is part of receiver.
+ *
+ * receiver is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * receiver is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with receiver.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef RECEIVER_UTIL_H_
+#define RECEIVER_UTIL_H_
+
+#define STR_IMPL(x) #x
+#define STR(x) STR_IMPL(x)
+#define LOG(fmt, ...) \
+  fprintf(stderr, __FILE__ ":" STR(__LINE__) " " fmt "\n", ##__VA_ARGS__)
+#define AUTO(x) x __attribute__((__cleanup__(x##Destroy)))
+#define SWAP(a, b) Swap((void**)&a, (void**)&b)
+#define RELEASE(x) Release((void**)&x)
+#define LENGTH(x) (sizeof(x) / sizeof *(x))
+#define MAX(a, b) ((a) > (b) ? (a) : (b))
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+
+static inline void Swap(void** a, void** b) {
+  void* temp = *a;
+  *a = *b;
+  *b = temp;
+}
+
+static inline void* Release(void** x) {
+  void* result = *x;
+  *x = 0;
+  return result;
+}
+
+#endif  // RECEIVER_UTIL_H_
diff --git a/window.c b/window.c
new file mode 100644
index 0000000..610fe85
--- /dev/null
+++ b/window.c
@@ -0,0 +1,338 @@
+/*
+ * Copyright (C) 2023 Mikhail Burakov. This file is part of receiver.
+ *
+ * receiver is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * receiver is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with receiver.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "window.h"
+
+#include <errno.h>
+#include <signal.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <wayland-client.h>
+
+#include "frame.h"
+#include "linux-dmabuf-unstable-v1.h"
+#include "util.h"
+#include "xdg-shell.h"
+
+struct Window {
+  struct wl_display* wl_display;
+  struct wl_surface* wl_surface;
+  struct xdg_wm_base* xdg_wm_base;
+  struct zwp_linux_dmabuf_v1* zwp_linux_dmabuf_v1;
+  struct xdg_surface* xdg_surface;
+  struct xdg_toplevel* xdg_toplevel;
+  struct wl_buffer* wl_buffer;
+};
+
+static void wl_registryDestroy(struct wl_registry** wl_registry) {
+  if (!wl_registry || !*wl_registry) return;
+  wl_registry_destroy(*wl_registry);
+  *wl_registry = NULL;
+}
+
+static void wl_compositorDestroy(struct wl_compositor** wl_compositor) {
+  if (!wl_compositor || !*wl_compositor) return;
+  wl_compositor_destroy(*wl_compositor);
+  *wl_compositor = NULL;
+}
+
+static void xdg_wm_baseDestroy(struct xdg_wm_base** xdg_wm_base) {
+  if (!xdg_wm_base || !*xdg_wm_base) return;
+  xdg_wm_base_destroy(*xdg_wm_base);
+  *xdg_wm_base = NULL;
+}
+
+static void zwp_linux_buffer_params_v1Destroy(
+    struct zwp_linux_buffer_params_v1** zwp_linux_buffer_params_v1) {
+  if (!zwp_linux_buffer_params_v1 || !*zwp_linux_buffer_params_v1) return;
+  zwp_linux_buffer_params_v1_destroy(*zwp_linux_buffer_params_v1);
+  *zwp_linux_buffer_params_v1 = NULL;
+}
+
+static void wl_bufferDestroy(struct wl_buffer** wl_buffer) {
+  if (!wl_buffer || !*wl_buffer) return;
+  wl_buffer_destroy(*wl_buffer);
+  *wl_buffer = NULL;
+}
+
+static void OnWmBasePing(void* data, struct xdg_wm_base* xdg_wm_base,
+                         uint32_t serial) {
+  (void)data;
+  xdg_wm_base_pong(xdg_wm_base, serial);
+}
+
+static void OnRegistryGlobal(void* data, struct wl_registry* registry,
+                             uint32_t name, const char* interface,
+                             uint32_t version) {
+  struct Window* window = data;
+  if (!strcmp(interface, wl_compositor_interface.name)) {
+    struct AUTO(wl_compositor)* compositor =
+        wl_registry_bind(registry, name, &wl_compositor_interface, version);
+    if (!compositor) {
+      LOG("Failed to bind wayland compositor (%s)", strerror(errno));
+      return;
+    }
+    window->wl_surface = wl_compositor_create_surface(compositor);
+    if (!window->wl_surface) {
+      LOG("Failed to create wayland surface (%s)", strerror(errno));
+      return;
+    }
+  } else if (!strcmp(interface, xdg_wm_base_interface.name)) {
+    struct AUTO(xdg_wm_base)* xdg_wm_base =
+        wl_registry_bind(registry, name, &xdg_wm_base_interface, version);
+    if (!xdg_wm_base) {
+      LOG("Failed to bind wayland xdg_wm_base (%s)", strerror(errno));
+      return;
+    }
+    static const struct xdg_wm_base_listener wm_base_listener = {
+        .ping = OnWmBasePing,
+    };
+    if (xdg_wm_base_add_listener(xdg_wm_base, &wm_base_listener, NULL)) {
+      LOG("Failed to add wayland wm base listener (%s)", strerror(errno));
+      return;
+    }
+    window->xdg_wm_base = RELEASE(xdg_wm_base);
+  } else if (!strcmp(interface, zwp_linux_dmabuf_v1_interface.name)) {
+    window->zwp_linux_dmabuf_v1 = wl_registry_bind(
+        registry, name, &zwp_linux_dmabuf_v1_interface, version);
+    if (!window->zwp_linux_dmabuf_v1)
+      LOG("Failed to bind wayland zwp_linux_dmabuf_v1 (%s)", strerror(errno));
+  }
+}
+
+static void OnRegistryGlobalRemove(void* data, struct wl_registry* registry,
+                                   uint32_t name) {
+  (void)data;
+  (void)registry;
+  (void)name;
+}
+
+static void OnSurfaceConfigure(void* data, struct xdg_surface* xdg_surface,
+                               uint32_t serial) {
+  (void)data;
+  xdg_surface_ack_configure(xdg_surface, serial);
+}
+
+static void OnToplevelConfigure(void* data, struct xdg_toplevel* xdg_toplevel,
+                                int32_t width, int32_t height,
+                                struct wl_array* states) {
+  (void)data;
+  (void)xdg_toplevel;
+  (void)width;
+  (void)height;
+  (void)states;
+}
+
+static void OnToplevelClose(void* data, struct xdg_toplevel* xdg_toplevel) {
+  (void)data;
+  (void)xdg_toplevel;
+  raise(SIGINT);
+}
+
+static void OnToplevelConfigureBounds(void* data,
+                                      struct xdg_toplevel* xdg_toplevel,
+                                      int32_t width, int32_t height) {
+  (void)data;
+  (void)xdg_toplevel;
+  (void)width;
+  (void)height;
+}
+
+static void OnToplevelWmCapabilities(void* data,
+                                     struct xdg_toplevel* xdg_toplevel,
+                                     struct wl_array* capabilities) {
+  (void)data;
+  (void)xdg_toplevel;
+  (void)capabilities;
+}
+
+struct Window* WindowCreate(void) {
+  struct AUTO(Window)* window = malloc(sizeof(struct Window));
+  if (!window) {
+    LOG("Failed to allocate window (%s)", strerror(errno));
+    return NULL;
+  }
+  *window = (struct Window){
+      .wl_display = NULL,
+      .wl_surface = NULL,
+      .xdg_wm_base = NULL,
+      .zwp_linux_dmabuf_v1 = NULL,
+      .xdg_surface = NULL,
+      .xdg_toplevel = NULL,
+      .wl_buffer = NULL,
+  };
+
+  window->wl_display = wl_display_connect(NULL);
+  if (!window->wl_display) {
+    LOG("Failed to connect wayland display (%s)", strerror(errno));
+    return NULL;
+  }
+
+  struct AUTO(wl_registry)* wl_registry =
+      wl_display_get_registry(window->wl_display);
+  if (!wl_registry) {
+    LOG("Failed to get wayland registry (%s)", strerror(errno));
+    return NULL;
+  }
+  static const struct wl_registry_listener wl_registry_listener = {
+      .global = OnRegistryGlobal,
+      .global_remove = OnRegistryGlobalRemove,
+  };
+  if (wl_registry_add_listener(wl_registry, &wl_registry_listener, window)) {
+    LOG("Failed to set wayland registry listener (%s)", strerror(errno));
+    return NULL;
+  }
+  if (wl_display_roundtrip(window->wl_display) == -1) {
+    LOG("Failed to roundtrip wayland display (%s)", strerror(errno));
+    return NULL;
+  }
+
+  if (!window->wl_surface || !window->xdg_wm_base ||
+      !window->zwp_linux_dmabuf_v1) {
+    LOG("Some wayland objects are missing");
+    return NULL;
+  }
+  window->xdg_surface =
+      xdg_wm_base_get_xdg_surface(window->xdg_wm_base, window->wl_surface);
+  if (!window->xdg_surface) {
+    LOG("Failed to get wayland surface (%s)", strerror(errno));
+    return NULL;
+  }
+  static const struct xdg_surface_listener xdg_surface_listener = {
+      .configure = OnSurfaceConfigure,
+  };
+  if (xdg_surface_add_listener(window->xdg_surface, &xdg_surface_listener,
+                               NULL)) {
+    LOG("Failed to add wayland surface listener (%s)", strerror(errno));
+    return NULL;
+  }
+  window->xdg_toplevel = xdg_surface_get_toplevel(window->xdg_surface);
+  if (!window->xdg_toplevel) {
+    LOG("Failed to get wayland toplevel (%s)", strerror(errno));
+    return NULL;
+  }
+  static const struct xdg_toplevel_listener xdg_toplevel_listener = {
+      .configure = OnToplevelConfigure,
+      .close = OnToplevelClose,
+      .configure_bounds = OnToplevelConfigureBounds,
+      .wm_capabilities = OnToplevelWmCapabilities,
+  };
+  if (xdg_toplevel_add_listener(window->xdg_toplevel, &xdg_toplevel_listener,
+                                NULL)) {
+    LOG("Failed to add wayland toplevel listener (%s)", strerror(errno));
+    return NULL;
+  }
+  xdg_toplevel_set_fullscreen(window->xdg_toplevel, NULL);
+  wl_surface_commit(window->wl_surface);
+  return RELEASE(window);
+}
+
+int WindowGetEventsFd(const struct Window* window) {
+  int events_fd = wl_display_get_fd(window->wl_display);
+  if (events_fd == -1)
+    LOG("Failed to get wayland display fd (%s)", strerror(errno));
+  return events_fd;
+}
+
+bool WindowProcessEvents(const struct Window* window) {
+  if (wl_display_dispatch(window->wl_display) == -1) {
+    LOG("Failed to dispatch wayland display (%s)", strerror(errno));
+    return false;
+  }
+  return true;
+}
+
+static void OnZwpLinuxBufferParamsCreated(
+    void* data, struct zwp_linux_buffer_params_v1* zwp_linux_buffer_params_v1,
+    struct wl_buffer* buffer) {
+  (void)zwp_linux_buffer_params_v1;
+  struct wl_buffer** wl_buffer = data;
+  *wl_buffer = buffer;
+}
+
+static void OnZwpLinuxBufferParamsFailed(
+    void* data, struct zwp_linux_buffer_params_v1* zwp_linux_buffer_params_v1) {
+  (void)data;
+  (void)zwp_linux_buffer_params_v1;
+}
+
+bool WindowRenderFrame(struct Window* window, const struct Frame* frame) {
+  struct AUTO(zwp_linux_buffer_params_v1)* zwp_linux_buffer_params_v1 =
+      zwp_linux_dmabuf_v1_create_params(window->zwp_linux_dmabuf_v1);
+  if (!zwp_linux_buffer_params_v1) {
+    LOG("Failed to create wayland dmabuf params (%s)", strerror(errno));
+    return false;
+  }
+
+  struct AUTO(wl_buffer)* wl_buffer = NULL;
+  static const struct zwp_linux_buffer_params_v1_listener
+      zwp_linux_buffer_params_v1_listener = {
+          .created = OnZwpLinuxBufferParamsCreated,
+          .failed = OnZwpLinuxBufferParamsFailed,
+      };
+  if (zwp_linux_buffer_params_v1_add_listener(
+          zwp_linux_buffer_params_v1, &zwp_linux_buffer_params_v1_listener,
+          &wl_buffer)) {
+    LOG("Failed to add buffer wayland dmabuf params listener (%s)",
+        strerror(errno));
+    return false;
+  }
+
+  for (size_t i = 0; i < frame->nplanes; i++) {
+    zwp_linux_buffer_params_v1_add(
+        zwp_linux_buffer_params_v1, frame->planes[i].dmabuf_fd, (uint32_t)i,
+        frame->planes[i].offset, frame->planes[i].pitch,
+        frame->planes[i].modifier >> 32,
+        frame->planes[i].modifier & UINT32_MAX);
+  }
+  zwp_linux_buffer_params_v1_create(zwp_linux_buffer_params_v1,
+                                    (int)frame->width, (int)frame->height,
+                                    frame->fourcc, 0);
+  if (wl_display_roundtrip(window->wl_display) == -1) {
+    LOG("Failed to roundtrip wayland display (%s)", strerror(errno));
+    return false;
+  }
+  if (!wl_buffer) {
+    LOG("Failed to create wl_buffer");
+    return false;
+  }
+
+  SWAP(window->wl_buffer, wl_buffer);
+  wl_surface_attach(window->wl_surface, window->wl_buffer, 0, 0);
+  wl_surface_damage(window->wl_surface, 0, 0, INT32_MAX, INT32_MAX);
+  wl_surface_commit(window->wl_surface);
+  if (wl_display_roundtrip(window->wl_display) == -1) {
+    LOG("Failed to roundtrip wayland display (%s)", strerror(errno));
+    return false;
+  }
+  return true;
+}
+
+void WindowDestroy(struct Window** window) {
+  if (!window || !*window) return;
+  if ((*window)->xdg_toplevel) xdg_toplevel_destroy((*window)->xdg_toplevel);
+  if ((*window)->xdg_surface) xdg_surface_destroy((*window)->xdg_surface);
+  if ((*window)->zwp_linux_dmabuf_v1)
+    zwp_linux_dmabuf_v1_destroy((*window)->zwp_linux_dmabuf_v1);
+  if ((*window)->xdg_wm_base) xdg_wm_base_destroy((*window)->xdg_wm_base);
+  if ((*window)->wl_surface) wl_surface_destroy((*window)->wl_surface);
+  if ((*window)->wl_display) wl_display_disconnect((*window)->wl_display);
+  free(*window);
+  *window = NULL;
+}
diff --git a/window.h b/window.h
new file mode 100644
index 0000000..7ac3dbf
--- /dev/null
+++ b/window.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2023 Mikhail Burakov. This file is part of receiver.
+ *
+ * receiver is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * receiver is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with receiver.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef RECEIVER_WINDOW_H_
+#define RECEIVER_WINDOW_H_
+
+#include <stdbool.h>
+
+struct Window;
+struct Frame;
+
+struct Window* WindowCreate(void);
+int WindowGetEventsFd(const struct Window* window);
+bool WindowProcessEvents(const struct Window* window);
+bool WindowRenderFrame(struct Window* window, const struct Frame* frame);
+void WindowDestroy(struct Window** window);
+
+#endif  // RECEIVER_WINDOW_H_