Unseal the Sync- and AsyncInput traits (#1315)

Author: ia0

rust/lib/CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Minor
 
+- Unseal `SyncInput` and `AsyncInput` for custom file-like objects
 - Support files larger than 4GB on 32-bits architectures
 
 ## 1.0.2

rust/lib/src/future.rs

@@ -23,8 +23,7 @@ use ndarray::Array2;
 use ort::session::{NoSelectedOutputs, RunOptions};
 use ort::value::Tensor;
 
-use crate::input::AsyncInputApi;
-use crate::Result;
+use crate::{AsyncInput, Result};
 
 pub(crate) fn exec<T>(mut future: impl Future<Output = T>) -> T {
     let future = unsafe { Pin::new_unchecked(&mut future) };
@@ -37,7 +36,7 @@ pub(crate) fn exec<T>(mut future: impl Future<Output = T>) -> T {
 }
 
 pub(crate) trait Env {
-    type File: AsyncInputApi;
+    type File: AsyncInput;
     async fn symlink_metadata(path: &Path) -> Result<Metadata>;
     async fn open(path: &Path) -> Result<Self::File>;
     async fn ort_session_run(

rust/lib/src/input.rs

@@ -25,20 +25,16 @@ use crate::{ContentType, Result};
 pub struct Features(pub(crate) Vec<i32>);
 
 /// Synchronous abstraction over file content.
-pub trait SyncInput: SyncInputApi {}
-
-/// Asynchronous abstraction over file content.
-pub trait AsyncInput: AsyncInputApi {}
-
-pub trait SyncInputApi {
+pub trait SyncInput {
     /// Returns the size of the input.
     fn length(&self) -> Result<u64>;
 
     /// Reads from the input at the given offset to fill the buffer.
     fn read_at(&mut self, buffer: &mut [u8], offset: u64) -> Result<()>;
 }
 
-pub trait AsyncInputApi {
+/// Asynchronous abstraction over file content.
+pub trait AsyncInput {
     /// Returns the size of the input.
     fn length(&self) -> impl Future<Output = Result<u64>>;
 
@@ -51,8 +47,7 @@ const _: () = const {
     assert!(std::mem::size_of::<usize>() <= std::mem::size_of::<u64>());
 };
 
-impl SyncInput for &[u8] {}
-impl SyncInputApi for &[u8] {
+impl SyncInput for &[u8] {
     fn length(&self) -> Result<u64> {
         Ok(self.len() as u64)
     }
@@ -64,8 +59,7 @@ impl SyncInputApi for &[u8] {
     }
 }
 
-impl SyncInput for std::fs::File {}
-impl SyncInputApi for std::fs::File {
+impl SyncInput for std::fs::File {
     fn length(&self) -> Result<u64> {
         Ok(self.metadata()?.len())
     }
@@ -76,18 +70,17 @@ impl SyncInputApi for std::fs::File {
     }
 }
 
-impl<T: SyncInputApi> SyncInput for &mut T {}
-impl<T: SyncInputApi> SyncInputApi for &mut T {
+impl<T: SyncInput> SyncInput for &mut T {
     fn length(&self) -> Result<u64> {
-        <T as SyncInputApi>::length(self)
+        <T as SyncInput>::length(self)
     }
 
     fn read_at(&mut self, buffer: &mut [u8], offset: u64) -> Result<()> {
-        <T as SyncInputApi>::read_at(self, buffer, offset)
+        <T as SyncInput>::read_at(self, buffer, offset)
     }
 }
 
-impl<T: SyncInputApi> AsyncInputApi for T {
+impl<T: SyncInput> AsyncInput for T {
     fn length(&self) -> impl Future<Output = Result<u64>> {
         std::future::ready(self.length())
     }
@@ -97,8 +90,7 @@ impl<T: SyncInputApi> AsyncInputApi for T {
     }
 }
 
-impl AsyncInput for tokio::fs::File {}
-impl AsyncInputApi for tokio::fs::File {
+impl AsyncInput for tokio::fs::File {
     async fn length(&self) -> Result<u64> {
         Ok(self.metadata().await?.len())
     }
@@ -134,7 +126,7 @@ impl FeaturesOrRuled {
         Self::extract(file).await
     }
 
-    pub(crate) async fn extract(file: impl AsyncInputApi) -> Result<Self> {
+    pub(crate) async fn extract(file: impl AsyncInput) -> Result<Self> {
         let config = &crate::model::CONFIG;
         let file_len = file.length().await?;
         if file_len == 0 {
@@ -154,7 +146,7 @@ impl FeaturesOrRuled {
 }
 
 async fn extract_features_async(
-    config: &ModelConfig, mut file: impl AsyncInputApi, file_len: u64,
+    config: &ModelConfig, mut file: impl AsyncInput, file_len: u64,
 ) -> Result<(Vec<u8>, Vec<i32>)> {
     debug_assert!(config.beg_size < config.block_size);
     debug_assert!(config.end_size < config.block_size);

rust/lib/src/session.rs

@@ -17,7 +17,6 @@ use std::path::Path;
 use ndarray::Array2;
 
 use crate::future::{exec, AsyncEnv, Env, SyncEnv};
-use crate::input::AsyncInputApi;
 use crate::{AsyncInput, Builder, Features, FeaturesOrRuled, FileType, Result, SyncInput};
 
 /// A Magika session to identify files.
@@ -69,7 +68,7 @@ impl Session {
         self.identify_content::<AsyncEnv>(file).await
     }
 
-    async fn identify_content<E: Env>(&mut self, file: impl AsyncInputApi) -> Result<FileType> {
+    async fn identify_content<E: Env>(&mut self, file: impl AsyncInput) -> Result<FileType> {
         match FeaturesOrRuled::extract(file).await? {
             FeaturesOrRuled::Ruled(content_type) => Ok(FileType::Ruled(content_type)),
             FeaturesOrRuled::Features(features) => self.identify_features::<E>(&features).await,