3 files changed, 41 insertions, 9 deletions

diff --git a/decode.c b/decode.c
index 7686e9e..89f7f34 100644
--- a/decode.c
+++ b/decode.c
@@ -43,6 +43,7 @@ struct Surface {
 struct DecodeContext {
   struct Window* window;
   mfxFrameAllocator allocator;
+  int dump_fd;
 
   int drm_fd;
   VADisplay va_display;
@@ -285,7 +286,8 @@ static const char* MfxStatusString(mfxStatus status) {
              : "???";
 }
 
-struct DecodeContext* DecodeContextCreate(struct Window* window) {
+struct DecodeContext* DecodeContextCreate(struct Window* window,
+                                          const char* dump_fname) {
   struct DecodeContext* decode_context = malloc(sizeof(struct DecodeContext));
   if (!decode_context) {
     LOG("Failed to allocate decode context (%s)", strerror(errno));
@@ -297,12 +299,22 @@ struct DecodeContext* DecodeContextCreate(struct Window* window) {
       .allocator.Alloc = OnAllocatorAlloc,
       .allocator.GetHDL = OnAllocatorGetHDL,
       .allocator.Free = OnAllocatorFree,
+      .dump_fd = -1,
   };
 
+  if (dump_fname) {
+    decode_context->dump_fd =
+        open(dump_fname, O_CREAT | O_TRUNC | O_WRONLY, 0644);
+    if (decode_context->dump_fd == -1) {
+      LOG("Failed to open video dump file (%s)", strerror(errno));
+      goto rollback_decode_context;
+    }
+  }
+
   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));
-    goto rollback_decode_context;
+    goto rollback_dump_fd;
   }
 
   decode_context->va_display = vaGetDisplayDRM(decode_context->drm_fd);
@@ -345,6 +357,8 @@ rollback_display:
   vaTerminate(decode_context->va_display);
 rollback_drm_fd:
   close(decode_context->drm_fd);
+rollback_dump_fd:
+  if (decode_context->dump_fd != -1) close(decode_context->dump_fd);
 rollback_decode_context:
   free(decode_context);
   return NULL;
@@ -387,8 +401,7 @@ static bool InitializeDecoder(struct DecodeContext* decode_context,
 
 static struct Surface* GetFreeSurface(struct DecodeContext* decode_context) {
   struct Surface** psurface = decode_context->surfaces;
-  for (; *psurface && (*psurface)->locked; psurface++)
-    ;
+  for (; *psurface && (*psurface)->locked; psurface++);
   (*psurface)->locked = true;
   return *psurface;
 }
@@ -408,6 +421,13 @@ static size_t UnlockAllSurfaces(struct DecodeContext* decode_context,
 
 bool DecodeContextDecode(struct DecodeContext* decode_context,
                          const void* buffer, size_t size) {
+  if (decode_context->dump_fd != -1) {
+    if (write(decode_context->dump_fd, buffer, size) != (ssize_t)size) {
+      LOG("Failed to write video dump file (%s)", strerror(errno));
+      return false;
+    }
+  }
+
   mfxBitstream bitstream = {
       .DecodeTimeStamp = MFX_TIMESTAMP_UNKNOWN,
       .TimeStamp = (mfxU64)MFX_TIMESTAMP_UNKNOWN,
@@ -477,5 +497,6 @@ void DecodeContextDestroy(struct DecodeContext* decode_context) {
   MFXClose(decode_context->mfx_session);
   vaTerminate(decode_context->va_display);
   close(decode_context->drm_fd);
+  if (decode_context->dump_fd != -1) close(decode_context->dump_fd);
   free(decode_context);
 }
diff --git a/decode.h b/decode.h
index e2ea3ba..c243316 100644
--- a/decode.h
+++ b/decode.h
@@ -24,7 +24,8 @@
 struct DecodeContext;
 struct Window;
 
-struct DecodeContext* DecodeContextCreate(struct Window* window);
+struct DecodeContext* DecodeContextCreate(struct Window* window,
+                                          const char* dump_fname);
 bool DecodeContextDecode(struct DecodeContext* decode_context,
                          const void* buffer, size_t size);
 void DecodeContextDestroy(struct DecodeContext* decode_context);
diff --git a/main.c b/main.c
index 4d6fdc6..04f7fbb 100644
--- a/main.c
+++ b/main.c
@@ -150,7 +150,8 @@ static void GetMaxOverlaySize(size_t* width, size_t* height) {
 }
 
 static struct Context* ContextCreate(int sock, bool no_input, bool stats,
-                                     const char* audio_buffer) {
+                                     const char* audio_buffer,
+                                     const char* dump_fname) {
   int audio_buffer_size = 0;
   if (audio_buffer) {
     audio_buffer_size = atoi(audio_buffer);
@@ -203,7 +204,7 @@ static struct Context* ContextCreate(int sock, bool no_input, bool stats,
     }
   }
 
-  context->decode_context = DecodeContextCreate(context->window);
+  context->decode_context = DecodeContextCreate(context->window, dump_fname);
   if (!context->decode_context) {
     LOG("Failed to create decode context");
     goto rollback_overlay;
@@ -456,7 +457,8 @@ static void ContextDestroy(struct Context* context) {
 
 int main(int argc, char* argv[]) {
   if (argc < 2) {
-    LOG("Usage: %s <ip>:<port> [--no-input] [--stats] [--audio <buffer_size>]",
+    LOG("Usage: %s <ip>:<port> [--no-input] [--stats] "
+        "[--audio <buffer_size>] [--dump-video <file_name>]",
         argv[0]);
     return EXIT_FAILURE;
   }
@@ -470,6 +472,7 @@ int main(int argc, char* argv[]) {
   bool no_input = false;
   bool stats = false;
   const char* audio_buffer = NULL;
+  const char* dump_fname = NULL;
   for (int i = 2; i < argc; i++) {
     if (!strcmp(argv[i], "--no-input")) {
       no_input = true;
@@ -481,10 +484,17 @@ int main(int argc, char* argv[]) {
         LOG("Audio argument requires a value");
         return EXIT_FAILURE;
       }
+    } else if (!strcmp(argv[i], "--dump-video")) {
+      dump_fname = argv[++i];
+      if (i == argc) {
+        LOG("Dump video argument requires a value");
+        return EXIT_FAILURE;
+      }
     }
   }
 
-  struct Context* context = ContextCreate(sock, no_input, stats, audio_buffer);
+  struct Context* context =
+      ContextCreate(sock, no_input, stats, audio_buffer, dump_fname);
   if (!context) {
     LOG("Failed to create context");
     goto rollback_socket;