Changed blob to use DataSlice with Arc in order to limit wasteful copying of byte vector

This commit is contained in:
David Raifaizen 2016-01-06 19:41:52 -05:00
parent 238a8786de
commit 76f689cd06
7 changed files with 190 additions and 132 deletions

View file

@ -12,7 +12,7 @@ use dom::bindings::inheritance::Castable;
use dom::bindings::js::{JS, MutNullableHeap, Root};
use dom::bindings::refcounted::Trusted;
use dom::bindings::reflector::{Reflectable, reflect_dom_object};
use dom::blob::Blob;
use dom::blob::{Blob, DataSlice};
use dom::domexception::{DOMErrorName, DOMException};
use dom::event::{Event, EventBubbles, EventCancelable};
use dom::eventtarget::EventTarget;
@ -23,10 +23,8 @@ use encoding::types::{DecoderTrap, EncodingRef};
use hyper::mime::{Attr, Mime};
use rustc_serialize::base64::{CharacterSet, Config, Newline, ToBase64};
use script_task::ScriptTaskEventCategory::FileRead;
use script_task::{CommonScriptMsg, Runnable, ScriptChan, ScriptPort};
use script_task::{CommonScriptMsg, Runnable, ScriptChan};
use std::cell::Cell;
use std::sync::mpsc;
use std::sync::mpsc::Receiver;
use string_cache::Atom;
use util::str::DOMString;
use util::task::spawn_named;
@ -163,7 +161,7 @@ impl FileReader {
// https://w3c.github.io/FileAPI/#dfn-readAsText
pub fn process_read_eof(filereader: TrustedFileReader, gen_id: GenerationId,
data: ReadMetaData, blob_contents: Vec<u8>) {
data: ReadMetaData, blob_contents: DataSlice) {
let fr = filereader.root();
macro_rules! return_on_abort(
@ -178,11 +176,13 @@ impl FileReader {
// Step 8.1
fr.change_ready_state(FileReaderReadyState::Done);
// Step 8.2
let bytes = blob_contents.get_bytes();
let output = match data.function {
FileReaderFunction::ReadAsDataUrl =>
FileReader::perform_readasdataurl(data, blob_contents),
FileReader::perform_readasdataurl(data, bytes),
FileReaderFunction::ReadAsText =>
FileReader::perform_readastext(data, blob_contents),
FileReader::perform_readastext(data, bytes),
};
*fr.result.borrow_mut() = Some(output);
@ -200,12 +200,11 @@ impl FileReader {
}
// https://w3c.github.io/FileAPI/#dfn-readAsText
fn perform_readastext(data: ReadMetaData, blob_contents: Vec<u8>)
fn perform_readastext(data: ReadMetaData, blob_bytes: &[u8])
-> DOMString {
let blob_label = &data.label;
let blob_type = &data.blobtype;
let blob_bytes = &blob_contents[..];
//https://w3c.github.io/FileAPI/#encoding-determination
// Steps 1 & 2 & 3
@ -233,7 +232,7 @@ impl FileReader {
}
//https://w3c.github.io/FileAPI/#dfn-readAsDataURL
fn perform_readasdataurl(data: ReadMetaData, blob_contents: Vec<u8>)
fn perform_readasdataurl(data: ReadMetaData, bytes: &[u8])
-> DOMString {
let config = Config {
char_set: CharacterSet::UrlSafe,
@ -241,7 +240,7 @@ impl FileReader {
pad: true,
line_length: None
};
let base64 = blob_contents.to_base64(config);
let base64 = bytes.to_base64(config);
let output = if data.blobtype.is_empty() {
format!("data:base64,{}", base64)
@ -355,8 +354,8 @@ impl FileReader {
self.change_ready_state(FileReaderReadyState::Loading);
// Step 4
let (send, bytes) = mpsc::channel();
blob.read_out_buffer(send);
let blob_contents = blob.get_data().clone();
let type_ = blob.Type();
let load_data = ReadMetaData::new(String::from(type_), label.map(String::from), function);
@ -367,7 +366,7 @@ impl FileReader {
let script_chan = global.file_reading_task_source();
spawn_named("file reader async operation".to_owned(), move || {
perform_annotated_read_operation(gen_id, load_data, bytes, fr, script_chan)
perform_annotated_read_operation(gen_id, load_data, blob_contents, fr, script_chan)
});
Ok(())
}
@ -382,7 +381,7 @@ pub enum FileReaderEvent {
ProcessRead(TrustedFileReader, GenerationId),
ProcessReadData(TrustedFileReader, GenerationId),
ProcessReadError(TrustedFileReader, GenerationId, DOMErrorName),
ProcessReadEOF(TrustedFileReader, GenerationId, ReadMetaData, Vec<u8>)
ProcessReadEOF(TrustedFileReader, GenerationId, ReadMetaData, DataSlice)
}
impl Runnable for FileReaderEvent {
@ -406,7 +405,7 @@ impl Runnable for FileReaderEvent {
}
// https://w3c.github.io/FileAPI/#task-read-operation
fn perform_annotated_read_operation(gen_id: GenerationId, data: ReadMetaData, blob_contents: Receiver<Vec<u8>>,
fn perform_annotated_read_operation(gen_id: GenerationId, data: ReadMetaData, blob_contents: DataSlice,
filereader: TrustedFileReader, script_chan: Box<ScriptChan + Send>) {
let chan = &script_chan;
// Step 4
@ -416,16 +415,6 @@ fn perform_annotated_read_operation(gen_id: GenerationId, data: ReadMetaData, bl
let task = box FileReaderEvent::ProcessReadData(filereader.clone(), gen_id);
chan.send(CommonScriptMsg::RunnableMsg(FileRead, task)).unwrap();
let bytes = match blob_contents.recv() {
Ok(bytes) => bytes,
Err(_) => {
let task = box FileReaderEvent::ProcessReadError(filereader,
gen_id, DOMErrorName::NotFoundError);
chan.send(CommonScriptMsg::RunnableMsg(FileRead, task)).unwrap();
return;
}
};
let task = box FileReaderEvent::ProcessReadEOF(filereader, gen_id, data, bytes);
let task = box FileReaderEvent::ProcessReadEOF(filereader, gen_id, data, blob_contents);
chan.send(CommonScriptMsg::RunnableMsg(FileRead, task)).unwrap();
}