core: Made SwfSlice::to_subslice return an empty slice in case of errors

core/src/backend/audio/decoders.rs

@@ -306,7 +306,7 @@ impl Iterator for StreamTagReader {
                             self.mp3_samples_buffered += i32::from(num_samples);
                             audio_block = &audio_block[4..];
                         }
-                        *audio_data = swf_data.to_subslice(audio_block).unwrap();
+                        *audio_data = swf_data.to_subslice(audio_block);
                         Ok(())
                     }
                     TagCode::ShowFrame if compression == AudioCompression::Mp3 => {

core/src/binary_data.rs

@@ -5,6 +5,6 @@ pub type BinaryData = SwfSlice;
 
 impl BinaryData {
     pub fn from_swf_tag(movie: Arc<SwfMovie>, tag: &swf::DefineBinaryData) -> Self {
-        SwfSlice::from(movie).to_subslice(tag.data).unwrap()
+        SwfSlice::from(movie).to_subslice(tag.data)
     }
 }

core/src/tag_utils.rs

@@ -205,18 +205,18 @@ impl SwfSlice {
     ///
     /// This function returns None if the given slice is not a subslice of the
     /// current slice.
-    pub fn to_subslice(&self, slice: &[u8]) -> Option<Self> {
+    pub fn to_subslice(&self, slice: &[u8]) -> Self {
         let self_pval = self.movie.data().as_ptr() as usize;
         let slice_pval = slice.as_ptr() as usize;
 
         if (self_pval + self.start) <= slice_pval && slice_pval < (self_pval + self.end) {
-            Some(Self {
+            Self {
                 movie: self.movie.clone(),
                 start: slice_pval - self_pval,
                 end: (slice_pval - self_pval) + slice.len(),
-            })
+            }
         } else {
-            None
+            self.copy_empty()
         }
     }
 
@@ -289,7 +289,6 @@ impl SwfSlice {
         if new_start <= new_end {
             if let Some(result) = self.movie.data().get(new_start..new_end) {
                 self.to_subslice(result)
-                    .unwrap_or_else(|| self.copy_empty())
             } else {
                 self.copy_empty()
             }