Implement read methods on FileReaderSync

components/script/dom/filereadersync.rs

@@ -2,17 +2,25 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use dom::bindings::codegen::Bindings::FileReaderSyncBinding;
-use dom::bindings::error::Fallible;
+use dom::bindings::codegen::Bindings::BlobBinding::BlobMethods;
+use dom::bindings::codegen::Bindings::FileReaderSyncBinding::{FileReaderSyncBinding, FileReaderSyncMethods};
+use dom::bindings::error::{Error, Fallible};
 use dom::bindings::reflector::reflect_dom_object;
 use dom::bindings::root::DomRoot;
+use dom::bindings::str::DOMString;
+use dom::blob::Blob;
 use dom::eventtarget::EventTarget;
+use dom::filereader::FileReaderSharedFunctionality;
 use dom::globalscope::GlobalScope;
 use dom_struct::dom_struct;
+use js::jsapi::{JSContext, JSObject};
+use js::typedarray::{ArrayBuffer, CreateWith};
+use std::ptr;
+use std::ptr::NonNull;
 
 #[dom_struct]
 pub struct FileReaderSync {
-    eventtarget: EventTarget
+    eventtarget: EventTarget,
 }
 
 impl FileReaderSync {
@@ -23,11 +31,79 @@ impl FileReaderSync {
     }
 
     pub fn new(global: &GlobalScope) -> DomRoot<FileReaderSync> {
-        reflect_dom_object(Box::new(FileReaderSync::new_inherited()),
-                           global, FileReaderSyncBinding::Wrap)
+        reflect_dom_object(
+            Box::new(FileReaderSync::new_inherited()),
+            global,
+            FileReaderSyncBinding::Wrap,
+        )
     }
 
     pub fn Constructor(global: &GlobalScope) -> Fallible<DomRoot<FileReaderSync>> {
         Ok(FileReaderSync::new(global))
     }
+
+    fn get_blob_bytes(blob: &Blob) -> Result<Vec<u8>, Error> {
+        blob.get_bytes().map_err(|_| Error::NotReadable)
+    }
+}
+
+impl FileReaderSyncMethods for FileReaderSync {
+    // https://w3c.github.io/FileAPI/#readAsBinaryStringSyncSection
+    fn ReadAsBinaryString(&self, blob: &Blob) -> Fallible<DOMString> {
+        // step 1
+        let blob_contents = FileReaderSync::get_blob_bytes(blob)?;
+
+        // step 2
+        Ok(DOMString::from(String::from_utf8_lossy(&blob_contents)))
+    }
+
+    // https://w3c.github.io/FileAPI/#readAsTextSync
+    fn ReadAsText(&self, blob: &Blob, label: Option<DOMString>) -> Fallible<DOMString> {
+        // step 1
+        let blob_contents = FileReaderSync::get_blob_bytes(blob)?;
+
+        // step 2
+        let blob_label = label.map(String::from);
+        let blob_type = String::from(blob.Type());
+
+        let output =
+            FileReaderSharedFunctionality::text_decode(&blob_contents, &blob_type, &blob_label);
+
+        Ok(output)
+    }
+
+    // https://w3c.github.io/FileAPI/#readAsDataURLSync-section
+    fn ReadAsDataURL(&self, blob: &Blob) -> Fallible<DOMString> {
+        // step 1
+        let blob_contents = FileReaderSync::get_blob_bytes(blob)?;
+
+        // step 2
+        let output =
+            FileReaderSharedFunctionality::dataurl_format(&blob_contents, blob.Type().to_string());
+
+        Ok(output)
+    }
+
+    #[allow(unsafe_code)]
+    // https://w3c.github.io/FileAPI/#readAsArrayBufferSyncSection
+    unsafe fn ReadAsArrayBuffer(
+        &self,
+        cx: *mut JSContext,
+        blob: &Blob,
+    ) -> Fallible<NonNull<JSObject>> {
+        // step 1
+        let blob_contents = FileReaderSync::get_blob_bytes(blob)?;
+
+        // step 2
+        rooted!(in(cx) let mut array_buffer = ptr::null_mut::<JSObject>());
+        assert!(
+            ArrayBuffer::create(
+                cx,
+                CreateWith::Slice(&blob_contents),
+                array_buffer.handle_mut()
+            ).is_ok()
+        );
+
+        Ok(NonNull::new_unchecked(array_buffer.get()))
+    }
 }