Added in an option to specify ebml size byte length; bump to version …

…0.6.0; realized I also had some updates to the async side... probably need to test those more since they were just sitting here uncommitted for awhile

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ebml-iterable"
-version = "0.5.0"
+version = "0.6.0"
 authors = ["Austin Blake <austinl3roy@gmail.com>"]
 edition = "2018"
 description = "This crate provides an iterator over EBML encoded data.  The items provided by the iterator are Tags as defined in EBML.  The iterator is spec-agnostic and requires a specification implementing specific traits to read files.  Typically, you would only use this crate to implement a custom specification - most often you would prefer a crate providing an existing specification, like `webm-iterable`."
@@ -16,7 +16,7 @@ repository = "https://github.com/austinleroy/ebml-iterable"
 [dependencies]
 ebml-iterable-specification = { version = "=0.4.0", path = "specification" }
 ebml-iterable-specification-derive = { version = "=0.4.0", path = "specification-derive", optional = true }
-futures = "0.3.21"
+futures = { version = "0.3.28", optional = true }
 
 [features]
 derive-spec = ["ebml-iterable-specification-derive"]

README.md

@@ -6,7 +6,7 @@ binary version of XML. It's used for container formats like [WebM][webm] or
 
 ```Cargo.toml
 [dependencies]
-ebml-iterable = "0.5.0"
+ebml-iterable = "0.6.0"
 ```
 
 # Usage

src/lib.rs

@@ -25,16 +25,17 @@
 
 mod errors;
 mod tag_iterator;
-mod tag_iterator_async;
 mod tag_writer;
 pub mod tools;
 pub mod specs;
 mod tag_iterator_util;
 mod spec_util;
 
+#[cfg(feature = "futures")]
+pub mod nonblocking;
+
 pub use self::tag_iterator::TagIterator;
-pub use self::tag_iterator_async::TagIteratorAsync;
-pub use self::tag_writer::TagWriter;
+pub use self::tag_writer::{TagWriter, WriteOptions};
 
 pub mod iterator {
     pub use super::tag_iterator_util::AllowableErrors;

src/nonblocking.rs

@@ -0,0 +1,53 @@
+use std::io::Cursor;
+use ebml_iterable_specification::{EbmlSpecification, EbmlTag};
+use futures::{AsyncRead, AsyncReadExt, Stream};
+use crate::error::TagIteratorError;
+use crate::TagIterator;
+
+///
+/// This can be transformed into a [`Stream`] using [`into_stream`][TagIteratorAsync::into_stream], or consumed directly by calling [`.next().await`] in a loop.
+///
+/// The struct can be created with the [`new()`][TagIteratorAsync::new] function on any source that implements the [`futures::AsyncRead`] trait.
+///
+pub struct TagIteratorAsync<R: AsyncRead + Unpin, TSpec>
+    where
+        TSpec: EbmlSpecification<TSpec> + EbmlTag<TSpec> + Clone
+{
+    source: R,
+    buffer: Box<[u8]>,
+    iterator: TagIterator<Cursor<Vec<u8>>, TSpec>
+}
+
+impl<R: AsyncRead + Unpin, TSpec> TagIteratorAsync<R, TSpec>
+    where
+        TSpec: EbmlSpecification<TSpec> + EbmlTag<TSpec> + Clone
+{
+
+    pub fn new(source: R, tags_to_buffer: &[TSpec]) -> Self {
+        let buffer = vec![0u8; 1024 * 64];
+        Self {
+            source,
+            buffer: buffer.into_boxed_slice(), 
+            iterator: TagIterator::new(Cursor::new(Vec::new()), tags_to_buffer)
+        }
+    }
+
+    pub async fn next(&mut self) -> Option<Result<TSpec, TagIteratorError>> {
+        match self.source.read(&mut self.buffer).await {
+            Ok(len) => {
+                self.iterator.get_mut().get_mut().append(&mut self.buffer[..len].to_vec());
+                self.iterator.next()
+            },
+            Err(e) => {
+                Some(Err(TagIteratorError::ReadError { source: e }))
+            }
+        } 
+    }
+
+    pub fn into_stream(self) -> impl Stream<Item=Result<TSpec, TagIteratorError>> {
+        futures::stream::unfold(self, |mut read| async {
+            let next = read.next().await;
+            next.map(move |it| (it, read))
+        })
+    }
+}

src/spec_util.rs

@@ -39,7 +39,7 @@ pub fn is_ended_by<T: EbmlSpecification<T> + EbmlTag<T> + Clone>(current_id: u64
 }
 
 #[inline(always)]
-pub fn validate_tag_path<T: EbmlSpecification<T> + EbmlTag<T> + Clone>(tag_id: u64, doc_path: impl Iterator<Item = (u64, EBMLSize)>) -> bool {
+pub fn validate_tag_path<T: EbmlSpecification<T> + EbmlTag<T> + Clone>(tag_id: u64, doc_path: impl Iterator<Item = (u64, EBMLSize, usize)>) -> bool {
     let path = <T>::get_path_by_id(tag_id);
     let mut path_marker = 0;
     let mut global_counter = 0;

src/tag_iterator.rs

@@ -506,7 +506,7 @@ impl<R: Read, TSpec> TagIterator<R, TSpec>
 
     #[inline(always)]
     fn validate_tag_path(&self, tag_id: u64) -> bool {
-        validate_tag_path::<TSpec>(tag_id, self.tag_stack.iter().map(|p| (p.tag.get_id(), p.size)))
+        validate_tag_path::<TSpec>(tag_id, self.tag_stack.iter().map(|p| (p.tag.get_id(), p.size, 0)))
     }
 
     #[inline(always)]