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servo/components/script/dom/htmlimageelement.rs

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/* This Source Code Form is subject to the terms of the Mozilla Public
* 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 app_units::{Au, AU_PER_PX};
use cssparser::{Parser, ParserInput};
use document_loader::{LoadType, LoadBlocker};
use dom::activation::Activatable;
use dom::attr::Attr;
use dom::bindings::cell::DomRefCell;
use dom::bindings::codegen::Bindings::DOMRectBinding::DOMRectBinding::DOMRectMethods;
use dom::bindings::codegen::Bindings::ElementBinding::ElementBinding::ElementMethods;
use dom::bindings::codegen::Bindings::HTMLImageElementBinding;
use dom::bindings::codegen::Bindings::HTMLImageElementBinding::HTMLImageElementMethods;
use dom::bindings::codegen::Bindings::MouseEventBinding::MouseEventMethods;
use dom::bindings::codegen::Bindings::NodeBinding::NodeBinding::NodeMethods;
use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
use dom::bindings::error::Fallible;
use dom::bindings::inheritance::Castable;
use dom::bindings::refcounted::Trusted;
use dom::bindings::reflector::DomObject;
use dom::bindings::root::{DomRoot, LayoutDom, MutNullableDom};
use dom::bindings::str::DOMString;
use dom::document::Document;
use dom::element::{AttributeMutation, Element, RawLayoutElementHelpers};
use dom::element::{reflect_cross_origin_attribute, set_cross_origin_attribute};
use dom::event::{Event, EventBubbles, EventCancelable};
use dom::eventtarget::EventTarget;
use dom::htmlareaelement::HTMLAreaElement;
use dom::htmlelement::HTMLElement;
use dom::htmlformelement::{FormControl, HTMLFormElement};
use dom::htmlmapelement::HTMLMapElement;
use dom::htmlpictureelement::HTMLPictureElement;
use dom::htmlsourceelement::HTMLSourceElement;
use dom::mouseevent::MouseEvent;
use dom::node::{Node, NodeDamage, document_from_node, window_from_node, UnbindContext};
use dom::progressevent::ProgressEvent;
use dom::values::UNSIGNED_LONG_MAX;
use dom::virtualmethods::VirtualMethods;
use dom::window::Window;
use dom_struct::dom_struct;
use euclid::Point2D;
use html5ever::{LocalName, Prefix};
use ipc_channel::ipc;
use ipc_channel::router::ROUTER;
use microtask::{Microtask, MicrotaskRunnable};
use mime::{Mime, TopLevel, SubLevel};
use net_traits::{FetchResponseListener, FetchMetadata, NetworkError, FetchResponseMsg};
use net_traits::image::base::{Image, ImageMetadata};
use net_traits::image_cache::{CanRequestImages, ImageCache, ImageOrMetadataAvailable};
use net_traits::image_cache::{ImageResponder, ImageResponse, ImageState, PendingImageId};
use net_traits::image_cache::UsePlaceholder;
use net_traits::request::RequestInit;
use network_listener::{NetworkListener, PreInvoke};
use num_traits::ToPrimitive;
use script_thread::ScriptThread;
use servo_url::ServoUrl;
use servo_url::origin::MutableOrigin;
use std::cell::{Cell, RefMut};
use std::char;
use std::collections::HashSet;
use std::default::Default;
use std::i32;
use std::mem;
use std::sync::{Arc, Mutex};
use style::attr::{AttrValue, LengthOrPercentageOrAuto, parse_double, parse_length, parse_unsigned_integer};
use style::context::QuirksMode;
use style::media_queries::MediaList;
use style::parser::ParserContext;
use style::str::is_ascii_digit;
use style::stylesheets::{CssRuleType, Origin};
use style::values::specified::{AbsoluteLength, source_size_list::SourceSizeList};
use style::values::specified::length::{Length, NoCalcLength};
use style_traits::ParsingMode;
use task_source::{TaskSource, TaskSourceName};
enum ParseState {
InDescriptor,
InParens,
AfterDescriptor,
}
pub struct SourceSet {
image_sources: Vec<ImageSource>,
source_size: SourceSizeList,
}
impl SourceSet {
fn new() -> SourceSet {
SourceSet {
image_sources: Vec::new(),
source_size: SourceSizeList::empty(),
}
}
}
#[derive(Clone, Debug, PartialEq)]
pub struct ImageSource {
pub url: String,
pub descriptor: Descriptor,
}
#[derive(Clone, Debug, PartialEq)]
pub struct Descriptor {
pub wid: Option<u32>,
pub den: Option<f64>,
}
#[derive(Clone, Copy, JSTraceable, MallocSizeOf)]
#[allow(dead_code)]
enum State {
Unavailable,
PartiallyAvailable,
CompletelyAvailable,
Broken,
}
#[derive(Clone, Copy, JSTraceable, MallocSizeOf)]
enum ImageRequestPhase {
Pending,
Current
}
#[derive(JSTraceable, MallocSizeOf)]
#[must_root]
struct ImageRequest {
state: State,
parsed_url: Option<ServoUrl>,
source_url: Option<DOMString>,
blocker: Option<LoadBlocker>,
#[ignore_malloc_size_of = "Arc"]
image: Option<Arc<Image>>,
metadata: Option<ImageMetadata>,
final_url: Option<ServoUrl>,
current_pixel_density: Option<f64>,
}
#[dom_struct]
pub struct HTMLImageElement {
htmlelement: HTMLElement,
image_request: Cell<ImageRequestPhase>,
current_request: DomRefCell<ImageRequest>,
pending_request: DomRefCell<ImageRequest>,
form_owner: MutNullableDom<HTMLFormElement>,
generation: Cell<u32>,
#[ignore_malloc_size_of = "SourceSet"]
source_set: DomRefCell<SourceSet>,
last_selected_source: DomRefCell<Option<DOMString>>,
}
impl HTMLImageElement {
pub fn get_url(&self) -> Option<ServoUrl> {
self.current_request.borrow().parsed_url.clone()
}
}
/// The context required for asynchronously loading an external image.
struct ImageContext {
/// Reference to the script thread image cache.
image_cache: Arc<ImageCache>,
/// Indicates whether the request failed, and why
status: Result<(), NetworkError>,
/// The cache ID for this request.
id: PendingImageId,
/// Used to mark abort
aborted: Cell<bool>,
}
impl FetchResponseListener for ImageContext {
fn process_request_body(&mut self) {}
fn process_request_eof(&mut self) {}
fn process_response(&mut self, metadata: Result<FetchMetadata, NetworkError>) {
self.image_cache.notify_pending_response(
self.id,
FetchResponseMsg::ProcessResponse(metadata.clone()));
let metadata = metadata.ok().map(|meta| {
match meta {
FetchMetadata::Unfiltered(m) => m,
FetchMetadata::Filtered { unsafe_, .. } => unsafe_
}
});
// Step 14.5 of https://html.spec.whatwg.org/multipage/#img-environment-changes
if let Some(metadata) = metadata.as_ref() {
if let Some(ref content_type) = metadata.content_type {
match content_type.clone().into_inner().0 {
Mime(TopLevel::Multipart, SubLevel::Ext(s), _) => {
if s == "x-mixed-replace" {
self.aborted.set(true);
}
},
_ => ()
}
}
}
let status_code = metadata.as_ref().and_then(|m| {
m.status.as_ref().map(|&(code, _)| code)
}).unwrap_or(0);
self.status = match status_code {
0 => Err(NetworkError::Internal("No http status code received".to_owned())),
200...299 => Ok(()), // HTTP ok status codes
_ => Err(NetworkError::Internal(format!("HTTP error code {}", status_code)))
};
}
fn process_response_chunk(&mut self, payload: Vec<u8>) {
if self.status.is_ok() {
self.image_cache.notify_pending_response(
self.id,
FetchResponseMsg::ProcessResponseChunk(payload));
}
}
fn process_response_eof(&mut self, response: Result<(), NetworkError>) {
self.image_cache.notify_pending_response(
self.id,
FetchResponseMsg::ProcessResponseEOF(response));
}
}
impl PreInvoke for ImageContext {
fn should_invoke(&self) -> bool {
!self.aborted.get()
}
}
impl HTMLImageElement {
/// Update the current image with a valid URL.
fn fetch_image(&self, img_url: &ServoUrl) {
fn add_cache_listener_for_element(image_cache: Arc<ImageCache>,
id: PendingImageId,
elem: &HTMLImageElement) {
let trusted_node = Trusted::new(elem);
let (responder_sender, responder_receiver) = ipc::channel().unwrap();
let window = window_from_node(elem);
let task_source = window.networking_task_source();
let task_canceller = window.task_canceller(TaskSourceName::Networking);
let generation = elem.generation.get();
ROUTER.add_route(responder_receiver.to_opaque(), Box::new(move |message| {
debug!("Got image {:?}", message);
// Return the image via a message to the script thread, which marks
// the element as dirty and triggers a reflow.
let element = trusted_node.clone();
let image = message.to().unwrap();
// FIXME(nox): Why are errors silenced here?
let _ = task_source.queue_with_canceller(
task!(process_image_response: move || {
let element = element.root();
// Ignore any image response for a previous request that has been discarded.
if generation == element.generation.get() {
element.process_image_response(image);
}
}),
&task_canceller,
);
}));
image_cache.add_listener(id, ImageResponder::new(responder_sender, id));
}
let window = window_from_node(self);
let image_cache = window.image_cache();
let response =
image_cache.find_image_or_metadata(img_url.clone().into(),
UsePlaceholder::Yes,
CanRequestImages::Yes);
match response {
Ok(ImageOrMetadataAvailable::ImageAvailable(image, url)) => {
self.process_image_response(ImageResponse::Loaded(image, url));
}
Ok(ImageOrMetadataAvailable::MetadataAvailable(m)) => {
self.process_image_response(ImageResponse::MetadataLoaded(m));
}
Err(ImageState::Pending(id)) => {
add_cache_listener_for_element(image_cache.clone(), id, self);
}
Err(ImageState::LoadError) => {
self.process_image_response(ImageResponse::None);
}
Err(ImageState::NotRequested(id)) => {
add_cache_listener_for_element(image_cache, id, self);
self.fetch_request(img_url, id);
}
}
}
fn fetch_request(&self, img_url: &ServoUrl, id: PendingImageId) {
let document = document_from_node(self);
let window = window_from_node(self);
let context = Arc::new(Mutex::new(ImageContext {
image_cache: window.image_cache(),
status: Ok(()),
id: id,
aborted: Cell::new(false),
}));
let (action_sender, action_receiver) = ipc::channel().unwrap();
let listener = NetworkListener {
context: context,
task_source: window.networking_task_source(),
canceller: Some(window.task_canceller(TaskSourceName::Networking)),
};
ROUTER.add_route(action_receiver.to_opaque(), Box::new(move |message| {
listener.notify_fetch(message.to().unwrap());
}));
let request = RequestInit {
url: img_url.clone(),
origin: document.origin().immutable().clone(),
pipeline_id: Some(document.global().pipeline_id()),
.. RequestInit::default()
};
// This is a background load because the load blocker already fulfills the
// purpose of delaying the document's load event.
document.loader_mut().fetch_async_background(request, action_sender);
}
// Steps common to when an image has been loaded.
fn handle_loaded_image(&self, image: Arc<Image>, url: ServoUrl) {
self.current_request.borrow_mut().metadata = Some(ImageMetadata {
height: image.height,
width: image.width
});
self.current_request.borrow_mut().final_url = Some(url);
self.current_request.borrow_mut().image = Some(image);
self.current_request.borrow_mut().state = State::CompletelyAvailable;
LoadBlocker::terminate(&mut self.current_request.borrow_mut().blocker);
// Mark the node dirty
self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
}
/// Step 24 of https://html.spec.whatwg.org/multipage/#update-the-image-data
fn process_image_response(&self, image: ImageResponse) {
// TODO: Handle multipart/x-mixed-replace
let (trigger_image_load, trigger_image_error) = match (image, self.image_request.get()) {
(ImageResponse::Loaded(image, url), ImageRequestPhase::Current) => {
self.handle_loaded_image(image, url);
(true, false)
},
(ImageResponse::PlaceholderLoaded(image, url), ImageRequestPhase::Current) => {
self.handle_loaded_image(image, url);
(false, true)
},
(ImageResponse::Loaded(image, url), ImageRequestPhase::Pending) => {
self.abort_request(State::Unavailable, ImageRequestPhase::Pending);
self.image_request.set(ImageRequestPhase::Current);
self.handle_loaded_image(image, url);
(true, false)
},
(ImageResponse::PlaceholderLoaded(image, url), ImageRequestPhase::Pending) => {
self.abort_request(State::Unavailable, ImageRequestPhase::Pending);
self.image_request.set(ImageRequestPhase::Current);
self.handle_loaded_image(image, url);
(false, true)
},
(ImageResponse::MetadataLoaded(meta), ImageRequestPhase::Current) => {
self.current_request.borrow_mut().state = State::PartiallyAvailable;
self.current_request.borrow_mut().metadata = Some(meta);
(false, false)
},
(ImageResponse::MetadataLoaded(_), ImageRequestPhase::Pending) => {
self.pending_request.borrow_mut().state = State::PartiallyAvailable;
(false, false)
},
(ImageResponse::None, ImageRequestPhase::Current) => {
self.abort_request(State::Broken, ImageRequestPhase::Current);
(false, true)
},
(ImageResponse::None, ImageRequestPhase::Pending) => {
self.abort_request(State::Broken, ImageRequestPhase::Current);
self.abort_request(State::Broken, ImageRequestPhase::Pending);
self.image_request.set(ImageRequestPhase::Current);
(false, true)
},
};
// Fire image.onload and loadend
if trigger_image_load {
// TODO: https://html.spec.whatwg.org/multipage/#fire-a-progress-event-or-event
self.upcast::<EventTarget>().fire_event(atom!("load"));
self.upcast::<EventTarget>().fire_event(atom!("loadend"));
}
// Fire image.onerror
if trigger_image_error {
self.upcast::<EventTarget>().fire_event(atom!("error"));
self.upcast::<EventTarget>().fire_event(atom!("loadend"));
}
// Trigger reflow
let window = window_from_node(self);
window.add_pending_reflow();
}
fn process_image_response_for_environment_change(&self,
image: ImageResponse,
src: DOMString,
generation: u32,
selected_pixel_density: f64) {
match image {
ImageResponse::Loaded(image, url) | ImageResponse::PlaceholderLoaded(image, url) => {
self.pending_request.borrow_mut().metadata = Some(ImageMetadata {
height: image.height,
width: image.width
});
self.pending_request.borrow_mut().final_url = Some(url);
self.pending_request.borrow_mut().image = Some(image);
self.finish_reacting_to_environment_change(src, generation, selected_pixel_density);
},
ImageResponse::MetadataLoaded(meta) => {
self.pending_request.borrow_mut().metadata = Some(meta);
},
ImageResponse::None => {
self.abort_request(State::Unavailable, ImageRequestPhase::Pending);
},
};
}
/// <https://html.spec.whatwg.org/multipage/#abort-the-image-request>
fn abort_request(&self, state: State, request: ImageRequestPhase) {
let mut request = match request {
ImageRequestPhase::Current => self.current_request.borrow_mut(),
ImageRequestPhase::Pending => self.pending_request.borrow_mut(),
};
LoadBlocker::terminate(&mut request.blocker);
request.state = state;
request.image = None;
request.metadata = None;
}
/// <https://html.spec.whatwg.org/multipage/#update-the-source-set>
fn update_source_set(&self) {
// Step 1
*self.source_set.borrow_mut() = SourceSet::new();
// Step 2
let elem = self.upcast::<Element>();
let parent = elem.upcast::<Node>().GetParentElement();
let nodes;
let elements = match parent.as_ref() {
Some(p) => {
if p.is::<HTMLPictureElement>() {
nodes = p.upcast::<Node>().children();
nodes.filter_map(DomRoot::downcast::<Element>)
.map(|n| DomRoot::from_ref(&*n)).collect()
} else {
vec![DomRoot::from_ref(&*elem)]
}
}
None => {
vec![DomRoot::from_ref(&*elem)]
}
};
// Step 3
let width = match elem.get_attribute(&ns!(), &local_name!("width")) {
Some(x) => {
match parse_length(&x.value()) {
LengthOrPercentageOrAuto::Length(x) =>{
let abs_length = AbsoluteLength::Px(x.to_f32_px());
Some(Length::NoCalc(NoCalcLength::Absolute(abs_length)))
},
_ => None
}
},
None => None
};
// Step 4
for element in &elements {
// Step 4.1
if *element == DomRoot::from_ref(&*elem) {
let mut source_set = SourceSet::new();
// Step 4.1.1
if let Some(x) = element.get_attribute(&ns!(), &local_name!("srcset")) {
source_set.image_sources = parse_a_srcset_attribute(&x.value());
}
// Step 4.1.2
if let Some(x) = element.get_attribute(&ns!(), &local_name!("sizes")) {
source_set.source_size =
parse_a_sizes_attribute(DOMString::from_string(x.value().to_string()));
}
// Step 4.1.3
let src_attribute = element.get_string_attribute(&local_name!("src"));
let is_src_empty = src_attribute.is_empty();
let no_density_source_of_1 = source_set.image_sources.iter()
.all(|source| source.descriptor.den != Some(1.));
let no_width_descriptor = source_set.image_sources.iter()
.all(|source| source.descriptor.wid.is_none());
if !is_src_empty && no_density_source_of_1 && no_width_descriptor {
source_set.image_sources.push(ImageSource {
url: src_attribute.to_string(),
descriptor: Descriptor { wid: None, den: None }
})
}
// Step 4.1.4
self.normalise_source_densities(&mut source_set, width);
// Step 4.1.5
*self.source_set.borrow_mut() = source_set;
// Step 4.1.6
return;
}
// Step 4.2
if !element.is::<HTMLSourceElement>() {
continue;
}
// Step 4.3 - 4.4
let mut source_set = SourceSet::new();
match element.get_attribute(&ns!(), &local_name!("srcset")) {
Some(x) => {
source_set.image_sources = parse_a_srcset_attribute(&x.value());
}
_ => continue
}
// Step 4.5
if source_set.image_sources.is_empty() {
continue;
}
// Step 4.6
if let Some(x) = element.get_attribute(&ns!(), &local_name!("media")) {
if !self.matches_environment(x.value().to_string()) {
continue;
}
}
// Step 4.7
if let Some(x) = element.get_attribute(&ns!(), &local_name!("sizes")) {
source_set.source_size =
parse_a_sizes_attribute(DOMString::from_string(x.value().to_string()));
}
// Step 4.8
if let Some(x) = element.get_attribute(&ns!(), &local_name!("type")) {
// TODO Handle unsupported mime type
let mime = x.value().parse::<Mime>();
match mime {
Ok(m) =>
match m {
Mime(TopLevel::Image, _, _) => (),
_ => continue
},
_ => continue
}
}
// Step 4.9
self.normalise_source_densities(&mut source_set, width);
// Step 4.10
*self.source_set.borrow_mut() = source_set;
return;
}
}
fn evaluate_source_size_list(&self, source_size_list: &mut SourceSizeList, _width: Option<Length>) -> Au {
let document = document_from_node(self);
let device = document.device();
if !device.is_some() {
return Au(1);
}
let quirks_mode = document.quirks_mode();
//FIXME https://github.com/whatwg/html/issues/3832
source_size_list.evaluate(&device.unwrap(), quirks_mode)
}
/// https://html.spec.whatwg.org/multipage/#matches-the-environment
fn matches_environment(&self, media_query: String) -> bool {
let document = document_from_node(self);
let device = match document.device() {
Some(device) => device,
None => return false,
};
let quirks_mode = document.quirks_mode();
let document_url = &document.url();
// FIXME(emilio): This should do the same that we do for other media
// lists regarding the rule type and such, though it doesn't really
// matter right now...
//
// Also, ParsingMode::all() is wrong, and should be DEFAULT.
let context = ParserContext::new(
Origin::Author,
document_url,
Some(CssRuleType::Style),
ParsingMode::all(),
quirks_mode,
None,
None,
);
let mut parserInput = ParserInput::new(&media_query);
let mut parser = Parser::new(&mut parserInput);
let media_list = MediaList::parse(&context, &mut parser);
media_list.evaluate(&device, quirks_mode)
}
/// <https://html.spec.whatwg.org/multipage/#normalise-the-source-densities>
fn normalise_source_densities(&self, source_set: &mut SourceSet, width: Option<Length>) {
// Step 1
let mut source_size = &mut source_set.source_size;
// Find source_size_length for Step 2.2
let source_size_length = self.evaluate_source_size_list(&mut source_size, width);
// Step 2
for imgsource in &mut source_set.image_sources {
// Step 2.1
if imgsource.descriptor.den.is_some() {
continue;
}
// Step 2.2
if imgsource.descriptor.wid.is_some() {
let wid = imgsource.descriptor.wid.unwrap();
imgsource.descriptor.den = Some(wid as f64 / source_size_length.to_f64_px());
} else {
//Step 2.3
imgsource.descriptor.den = Some(1 as f64);
}
};
}
/// <https://html.spec.whatwg.org/multipage/#select-an-image-source>
fn select_image_source(&self) -> Option<(DOMString, f64)> {
// Step 1, 3
self.update_source_set();
let source_set = &*self.source_set.borrow_mut();
let len = source_set.image_sources.len();
// Step 2
if len == 0 {
return None;
}
// Step 4
let mut repeat_indices = HashSet::new();
for outer_index in 0..len {
if repeat_indices.contains(&outer_index) {
continue;
}
let imgsource = &source_set.image_sources[outer_index];
let pixel_density = imgsource.descriptor.den.unwrap();
for inner_index in (outer_index + 1)..len {
let imgsource2 = &source_set.image_sources[inner_index];
if pixel_density == imgsource2.descriptor.den.unwrap() {
repeat_indices.insert(inner_index);
}
}
}
let mut max = (0f64, 0);
let img_sources = &mut vec![];
for (index, image_source) in source_set.image_sources.iter().enumerate() {
if repeat_indices.contains(&index) {
continue;
}
let den = image_source.descriptor.den.unwrap();
if max.0 < den {
max = (den, img_sources.len());
}
img_sources.push(image_source);
}
// Step 5
let mut best_candidate = max;
let device = document_from_node(self).device();
if let Some(device) = device {
let device_den = device.device_pixel_ratio().get() as f64;
for (index, image_source) in img_sources.iter().enumerate() {
let current_den = image_source.descriptor.den.unwrap();
if current_den < best_candidate.0 && current_den >= device_den {
best_candidate = (current_den, index);
}
}
}
let selected_source = img_sources.remove(best_candidate.1).clone();
Some((DOMString::from_string(selected_source.url), selected_source.descriptor.den.unwrap() as f64))
}
fn init_image_request(&self,
request: &mut RefMut<ImageRequest>,
url: &ServoUrl,
src: &DOMString) {
request.parsed_url = Some(url.clone());
request.source_url = Some(src.clone());
request.image = None;
request.metadata = None;
let document = document_from_node(self);
LoadBlocker::terminate(&mut request.blocker);
request.blocker = Some(LoadBlocker::new(&*document, LoadType::Image(url.clone())));
}
/// Step 13-17 of html.spec.whatwg.org/multipage/#update-the-image-data
fn prepare_image_request(&self, url: &ServoUrl, src: &DOMString, selected_pixel_density: f64) {
match self.image_request.get() {
ImageRequestPhase::Pending => {
if let Some(pending_url) = self.pending_request.borrow().parsed_url.clone() {
// Step 13
if pending_url == *url {
return
}
}
},
ImageRequestPhase::Current => {
let mut current_request = self.current_request.borrow_mut();
let mut pending_request = self.pending_request.borrow_mut();
// step 16, create a new "image_request"
match (current_request.parsed_url.clone(), current_request.state) {
(Some(parsed_url), State::PartiallyAvailable) => {
// Step 14
if parsed_url == *url {
// Step 15 abort pending request
pending_request.image = None;
pending_request.parsed_url = None;
LoadBlocker::terminate(&mut pending_request.blocker);
// TODO: queue a task to restart animation, if restart-animation is set
return
}
pending_request.current_pixel_density = Some(selected_pixel_density);
self.image_request.set(ImageRequestPhase::Pending);
self.init_image_request(&mut pending_request, &url, &src);
},
(_, State::Broken) | (_, State::Unavailable) => {
// Step 17
current_request.current_pixel_density = Some(selected_pixel_density);
self.init_image_request(&mut current_request, &url, &src);
},
(_, _) => {
// step 17
pending_request.current_pixel_density = Some(selected_pixel_density);
self.image_request.set(ImageRequestPhase::Pending);
self.init_image_request(&mut pending_request, &url, &src);
},
}
}
}
self.fetch_image(&url);
}
/// Step 8-12 of html.spec.whatwg.org/multipage/#update-the-image-data
fn update_the_image_data_sync_steps(&self) {
let document = document_from_node(self);
let window = document.window();
let task_source = window.dom_manipulation_task_source();
let this = Trusted::new(self);
let (src, pixel_density) = match self.select_image_source() {
// Step 8
Some(data) => data,
None => {
// Step 9.
// FIXME(nox): Why are errors silenced here?
let _ = task_source.queue(
task!(image_null_source_error: move || {
let this = this.root();
{
let mut current_request =
this.current_request.borrow_mut();
current_request.source_url = None;
current_request.parsed_url = None;
}
let elem = this.upcast::<Element>();
let src_present = elem.has_attribute(&local_name!("src"));
if src_present || Self::uses_srcset_or_picture(elem) {
this.upcast::<EventTarget>().fire_event(atom!("error"));
}
// FIXME(nox): According to the spec, setting the current
// request to the broken state is done prior to queuing a
// task, why is this here?
this.abort_request(State::Broken, ImageRequestPhase::Current);
this.abort_request(State::Broken, ImageRequestPhase::Pending);
}),
window.upcast(),
);
return;
},
};
// Step 10.
let target = Trusted::new(self.upcast::<EventTarget>());
// FIXME(nox): Why are errors silenced here?
let _ = task_source.queue(
task!(fire_progress_event: move || {
let target = target.root();
let event = ProgressEvent::new(
&target.global(),
atom!("loadstart"),
EventBubbles::DoesNotBubble,
EventCancelable::NotCancelable,
false,
0,
0,
);
event.upcast::<Event>().fire(&target);
}),
window.upcast(),
);
// Step 11
let base_url = document.base_url();
let parsed_url = base_url.join(&src);
match parsed_url {
Ok(url) => {
// Step 13-17
self.prepare_image_request(&url, &src, pixel_density);
},
Err(_) => {
// Step 12.1-12.5.
let src = String::from(src);
// FIXME(nox): Why are errors silenced here?
let _ = task_source.queue(
task!(image_selected_source_error: move || {
let this = this.root();
{
let mut current_request =
this.current_request.borrow_mut();
current_request.source_url = Some(src.into());
}
this.upcast::<EventTarget>().fire_event(atom!("error"));
this.upcast::<EventTarget>().fire_event(atom!("loadend"));
// FIXME(nox): According to the spec, setting the current
// request to the broken state is done prior to queuing a
// task, why is this here?
this.abort_request(State::Broken, ImageRequestPhase::Current);
this.abort_request(State::Broken, ImageRequestPhase::Pending);
}),
window.upcast(),
);
}
}
}
/// <https://html.spec.whatwg.org/multipage/#update-the-image-data>
fn update_the_image_data(&self) {
let document = document_from_node(self);
let window = document.window();
let elem = self.upcast::<Element>();
let src = elem.get_string_attribute(&local_name!("src"));
let base_url = document.base_url();
// https://html.spec.whatwg.org/multipage/#reacting-to-dom-mutations
// Always first set the current request to unavailable,
// ensuring img.complete is false.
{
let mut current_request = self.current_request.borrow_mut();
current_request.state = State::Unavailable;
}
if !document.is_active() {
// Step 1 (if the document is inactive)
// TODO: use GlobalScope::enqueue_microtask,
// to queue micro task to come back to this algorithm
}
// Step 2 abort if user-agent does not supports images
// NOTE: Servo only supports images, skipping this step
// Step 3, 4
let mut selected_source = None;
let mut pixel_density = None;
let src_set = elem.get_string_attribute(&local_name!("srcset"));
let is_parent_picture = elem.upcast::<Node>().GetParentElement()
.map_or(false, |p| p.is::<HTMLPictureElement>());
if src_set.is_empty() && !is_parent_picture && !src.is_empty() {
selected_source = Some(src.clone());
pixel_density = Some(1 as f64);
};
// Step 5
*self.last_selected_source.borrow_mut() = selected_source.clone();
// Step 6, check the list of available images
if !selected_source.as_ref().map_or(false, |source| source.is_empty()) {
if let Ok(img_url) = base_url.join(&src) {
let image_cache = window.image_cache();
let response = image_cache.find_image_or_metadata(img_url.clone().into(),
UsePlaceholder::No,
CanRequestImages::No);
if let Ok(ImageOrMetadataAvailable::ImageAvailable(image, url)) = response {
// Step 6.3
let metadata = ImageMetadata { height: image.height, width: image.width };
// Step 6.3.2 abort requests
self.abort_request(State::CompletelyAvailable, ImageRequestPhase::Current);
self.abort_request(State::CompletelyAvailable, ImageRequestPhase::Pending);
let mut current_request = self.current_request.borrow_mut();
current_request.final_url = Some(url);
current_request.image = Some(image.clone());
current_request.metadata = Some(metadata);
// Step 6.3.6
current_request.current_pixel_density = pixel_density;
let this = Trusted::new(self);
let src = String::from(src);
let _ = window.dom_manipulation_task_source().queue(
task!(image_load_event: move || {
let this = this.root();
{
let mut current_request =
this.current_request.borrow_mut();
current_request.parsed_url = Some(img_url);
current_request.source_url = Some(src.into());
}
// TODO: restart animation, if set.
this.upcast::<EventTarget>().fire_event(atom!("load"));
}),
window.upcast(),
);
return;
}
}
}
// step 7, await a stable state.
self.generation.set(self.generation.get() + 1);
let task = ImageElementMicrotask::StableStateUpdateImageDataTask {
elem: DomRoot::from_ref(self),
generation: self.generation.get(),
};
ScriptThread::await_stable_state(Microtask::ImageElement(task));
}
/// <https://html.spec.whatwg.org/multipage/#img-environment-changes>
pub fn react_to_environment_changes(&self) {
// Step 1
let task = ImageElementMicrotask::EnvironmentChangesTask {
elem: DomRoot::from_ref(self),
generation: self.generation.get(),
};
ScriptThread::await_stable_state(Microtask::ImageElement(task));
}
/// Step 2-12 of https://html.spec.whatwg.org/multipage/#img-environment-changes
fn react_to_environment_changes_sync_steps(&self, generation: u32) {
// TODO reduce duplicacy of this code
fn add_cache_listener_for_element(image_cache: Arc<ImageCache>,
id: PendingImageId,
elem: &HTMLImageElement,
selected_source: String,
selected_pixel_density: f64) {
let trusted_node = Trusted::new(elem);
let (responder_sender, responder_receiver) = ipc::channel().unwrap();
let window = window_from_node(elem);
let task_source = window.networking_task_source();
let task_canceller = window.task_canceller(TaskSourceName::Networking);
let generation = elem.generation.get();
ROUTER.add_route(responder_receiver.to_opaque(), Box::new(move |message| {
debug!("Got image {:?}", message);
// Return the image via a message to the script thread, which marks
// the element as dirty and triggers a reflow.
let element = trusted_node.clone();
let image = message.to().unwrap();
let selected_source_clone = selected_source.clone();
let _ = task_source.queue_with_canceller(
task!(process_image_response_for_environment_change: move || {
let element = element.root();
// Ignore any image response for a previous request that has been discarded.
if generation == element.generation.get() {
element.process_image_response_for_environment_change(image,
DOMString::from_string(selected_source_clone), generation, selected_pixel_density);
}
}),
&task_canceller,
);
}));
image_cache.add_listener(id, ImageResponder::new(responder_sender, id));
}
let elem = self.upcast::<Element>();
let document = document_from_node(elem);
let has_pending_request = match self.image_request.get() {
ImageRequestPhase::Pending => true,
_ => false
};
// Step 2
if !document.is_active() || !Self::uses_srcset_or_picture(elem) || has_pending_request {
return;
}
// Steps 3-4
let (selected_source, selected_pixel_density) = match self.select_image_source() {
Some(selected) => selected,
None => return,
};
// Step 5
let same_source = match *self.last_selected_source.borrow() {
Some(ref last_src) => *last_src == selected_source,
_ => false,
};
let same_selected_pixel_density = match self.current_request.borrow().current_pixel_density {
Some(den) => selected_pixel_density == den,
_ => false,
};
if same_source && same_selected_pixel_density {
return;
}
let base_url = document.base_url();
// Step 6
let img_url = match base_url.join(&selected_source) {
Ok(url) => url,
Err(_) => return,
};
// Step 12
self.image_request.set(ImageRequestPhase::Pending);
self.init_image_request(&mut self.pending_request.borrow_mut(), &img_url, &selected_source);
let window = window_from_node(self);
let image_cache = window.image_cache();
// Step 14
let response =
image_cache.find_image_or_metadata(img_url.clone().into(),
UsePlaceholder::No,
CanRequestImages::Yes);
match response {
Ok(ImageOrMetadataAvailable::ImageAvailable(_image, _url)) => {
// Step 15
self.finish_reacting_to_environment_change(selected_source, generation, selected_pixel_density);
}
Ok(ImageOrMetadataAvailable::MetadataAvailable(m)) => {
self.process_image_response_for_environment_change(ImageResponse::MetadataLoaded(m),
selected_source, generation, selected_pixel_density);
}
Err(ImageState::Pending(id)) => {
add_cache_listener_for_element(image_cache.clone(), id, self,
selected_source.to_string(), selected_pixel_density);
}
Err(ImageState::LoadError) => {
self.process_image_response_for_environment_change(ImageResponse::None,
selected_source, generation, selected_pixel_density);
}
Err(ImageState::NotRequested(id)) => {
add_cache_listener_for_element(image_cache, id, self, selected_source.to_string(),
selected_pixel_density);
self.fetch_request(&img_url, id);
}
}
}
/// Step 15 for <https://html.spec.whatwg.org/multipage/#img-environment-changes>
fn finish_reacting_to_environment_change(&self, src: DOMString, generation: u32, selected_pixel_density: f64) {
let this = Trusted::new(self);
let window = window_from_node(self);
let src = src.to_string();
let _ = window.dom_manipulation_task_source().queue(
task!(image_load_event: move || {
let this = this.root();
let relevant_mutation = this.generation.get() != generation;
// Step 15.1
if relevant_mutation {
this.abort_request(State::Unavailable, ImageRequestPhase::Pending);
return;
}
// Step 15.2
*this.last_selected_source.borrow_mut() = Some(DOMString::from_string(src));
{
let mut pending_request = this.pending_request.borrow_mut();
pending_request.current_pixel_density = Some(selected_pixel_density);
// Step 15.3
pending_request.state = State::CompletelyAvailable;
// Step 15.4
// Already a part of the list of available images due to Step 14
// Step 15.5
mem::swap(&mut this.current_request.borrow_mut(), &mut pending_request);
this.abort_request(State::Unavailable, ImageRequestPhase::Pending);
}
// Step 15.6
this.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
// Step 15.7
this.upcast::<EventTarget>().fire_event(atom!("load"));
}),
window.upcast(),
);
}
fn uses_srcset_or_picture(elem: &Element) -> bool {
let has_src = elem.has_attribute(&local_name!("srcset"));
let is_parent_picture = elem.upcast::<Node>().GetParentElement()
.map_or(false, |p| p.is::<HTMLPictureElement>());
has_src || is_parent_picture
}
fn new_inherited(local_name: LocalName, prefix: Option<Prefix>, document: &Document) -> HTMLImageElement {
HTMLImageElement {
htmlelement: HTMLElement::new_inherited(local_name, prefix, document),
image_request: Cell::new(ImageRequestPhase::Current),
current_request: DomRefCell::new(ImageRequest {
state: State::Unavailable,
parsed_url: None,
source_url: None,
image: None,
metadata: None,
blocker: None,
final_url: None,
current_pixel_density: None,
}),
pending_request: DomRefCell::new(ImageRequest {
state: State::Unavailable,
parsed_url: None,
source_url: None,
image: None,
metadata: None,
blocker: None,
final_url: None,
current_pixel_density: None,
}),
form_owner: Default::default(),
generation: Default::default(),
source_set: DomRefCell::new(SourceSet::new()),
last_selected_source: DomRefCell::new(None),
}
}
#[allow(unrooted_must_root)]
pub fn new(local_name: LocalName,
prefix: Option<Prefix>,
document: &Document) -> DomRoot<HTMLImageElement> {
Node::reflect_node(Box::new(HTMLImageElement::new_inherited(local_name, prefix, document)),
document,
HTMLImageElementBinding::Wrap)
}
pub fn Image(window: &Window,
width: Option<u32>,
height: Option<u32>) -> Fallible<DomRoot<HTMLImageElement>> {
let document = window.Document();
let image = HTMLImageElement::new(local_name!("img"), None, &document);
if let Some(w) = width {
image.SetWidth(w);
}
if let Some(h) = height {
image.SetHeight(h);
}
Ok(image)
}
pub fn areas(&self) -> Option<Vec<DomRoot<HTMLAreaElement>>> {
let elem = self.upcast::<Element>();
let usemap_attr = elem.get_attribute(&ns!(), &local_name!("usemap"))?;
let value = usemap_attr.value();
if value.len() == 0 || !value.is_char_boundary(1) {
return None
}
let (first, last) = value.split_at(1);
if first != "#" || last.len() == 0 {
return None
}
let useMapElements = document_from_node(self).upcast::<Node>()
.traverse_preorder()
.filter_map(DomRoot::downcast::<HTMLMapElement>)
.find(|n| n.upcast::<Element>().get_string_attribute(&LocalName::from("name")) == last);
useMapElements.map(|mapElem| mapElem.get_area_elements())
}
pub fn same_origin(&self, origin: &MutableOrigin) -> bool {
self.current_request.borrow_mut().final_url.as_ref().map_or(false, |url| {
url.scheme() == "data" || url.origin().same_origin(origin)
})
}
}
#[derive(JSTraceable, MallocSizeOf)]
pub enum ImageElementMicrotask {
StableStateUpdateImageDataTask {
elem: DomRoot<HTMLImageElement>,
generation: u32,
},
EnvironmentChangesTask {
elem: DomRoot<HTMLImageElement>,
generation: u32,
}
}
impl MicrotaskRunnable for ImageElementMicrotask {
fn handler(&self) {
match self {
&ImageElementMicrotask::StableStateUpdateImageDataTask { ref elem, ref generation } => {
// Step 7 of https://html.spec.whatwg.org/multipage/#update-the-image-data,
// stop here if other instances of this algorithm have been scheduled
if elem.generation.get() == *generation {
elem.update_the_image_data_sync_steps();
}
},
&ImageElementMicrotask::EnvironmentChangesTask { ref elem, ref generation } => {
elem.react_to_environment_changes_sync_steps(*generation);
},
}
}
}
pub trait LayoutHTMLImageElementHelpers {
#[allow(unsafe_code)]
unsafe fn image(&self) -> Option<Arc<Image>>;
#[allow(unsafe_code)]
unsafe fn image_url(&self) -> Option<ServoUrl>;
#[allow(unsafe_code)]
unsafe fn image_density(&self) -> Option<f64>;
fn get_width(&self) -> LengthOrPercentageOrAuto;
fn get_height(&self) -> LengthOrPercentageOrAuto;
}
impl LayoutHTMLImageElementHelpers for LayoutDom<HTMLImageElement> {
#[allow(unsafe_code)]
unsafe fn image(&self) -> Option<Arc<Image>> {
(*self.unsafe_get()).current_request.borrow_for_layout().image.clone()
}
#[allow(unsafe_code)]
unsafe fn image_url(&self) -> Option<ServoUrl> {
(*self.unsafe_get()).current_request.borrow_for_layout().parsed_url.clone()
}
#[allow(unsafe_code)]
unsafe fn image_density(&self) -> Option<f64> {
(*self.unsafe_get()).current_request.borrow_for_layout().current_pixel_density.clone()
}
#[allow(unsafe_code)]
fn get_width(&self) -> LengthOrPercentageOrAuto {
unsafe {
(*self.upcast::<Element>().unsafe_get())
.get_attr_for_layout(&ns!(), &local_name!("width"))
.map(AttrValue::as_dimension)
.cloned()
.unwrap_or(LengthOrPercentageOrAuto::Auto)
}
}
#[allow(unsafe_code)]
fn get_height(&self) -> LengthOrPercentageOrAuto {
unsafe {
(*self.upcast::<Element>().unsafe_get())
.get_attr_for_layout(&ns!(), &local_name!("height"))
.map(AttrValue::as_dimension)
.cloned()
.unwrap_or(LengthOrPercentageOrAuto::Auto)
}
}
}
//https://html.spec.whatwg.org/multipage/#parse-a-sizes-attribute
pub fn parse_a_sizes_attribute(value: DOMString) -> SourceSizeList {
let mut input = ParserInput::new(&value);
let mut parser = Parser::new(&mut input);
let url = ServoUrl::parse("about:blank").unwrap();
let context = ParserContext::new(
Origin::Author,
&url,
Some(CssRuleType::Style),
// FIXME(emilio): why ::empty() instead of ::DEFAULT? Also, what do
// browsers do regarding quirks-mode in a media list?
ParsingMode::empty(),
QuirksMode::NoQuirks,
None,
None,
);
SourceSizeList::parse(&context, &mut parser)
}
impl HTMLImageElementMethods for HTMLImageElement {
// https://html.spec.whatwg.org/multipage/#dom-img-alt
make_getter!(Alt, "alt");
// https://html.spec.whatwg.org/multipage/#dom-img-alt
make_setter!(SetAlt, "alt");
// https://html.spec.whatwg.org/multipage/#dom-img-src
make_url_getter!(Src, "src");
// https://html.spec.whatwg.org/multipage/#dom-img-src
make_setter!(SetSrc, "src");
// https://html.spec.whatwg.org/multipage/#dom-img-crossOrigin
fn GetCrossOrigin(&self) -> Option<DOMString> {
reflect_cross_origin_attribute(self.upcast::<Element>())
}
// https://html.spec.whatwg.org/multipage/#dom-img-crossOrigin
fn SetCrossOrigin(&self, value: Option<DOMString>) {
set_cross_origin_attribute(self.upcast::<Element>(), value);
}
// https://html.spec.whatwg.org/multipage/#dom-img-usemap
make_getter!(UseMap, "usemap");
// https://html.spec.whatwg.org/multipage/#dom-img-usemap
make_setter!(SetUseMap, "usemap");
// https://html.spec.whatwg.org/multipage/#dom-img-ismap
make_bool_getter!(IsMap, "ismap");
// https://html.spec.whatwg.org/multipage/#dom-img-ismap
make_bool_setter!(SetIsMap, "ismap");
// https://html.spec.whatwg.org/multipage/#dom-img-width
fn Width(&self) -> u32 {
let node = self.upcast::<Node>();
match node.bounding_content_box() {
Some(rect) => rect.size.width.to_px() as u32,
None => self.NaturalWidth(),
}
}
// https://html.spec.whatwg.org/multipage/#dom-img-width
fn SetWidth(&self, value: u32) {
image_dimension_setter(self.upcast(), local_name!("width"), value);
}
// https://html.spec.whatwg.org/multipage/#dom-img-height
fn Height(&self) -> u32 {
let node = self.upcast::<Node>();
match node.bounding_content_box() {
Some(rect) => rect.size.height.to_px() as u32,
None => self.NaturalHeight(),
}
}
// https://html.spec.whatwg.org/multipage/#dom-img-height
fn SetHeight(&self, value: u32) {
image_dimension_setter(self.upcast(), local_name!("height"), value);
}
// https://html.spec.whatwg.org/multipage/#dom-img-naturalwidth
fn NaturalWidth(&self) -> u32 {
let request = self.current_request.borrow();
let pixel_density = request.current_pixel_density.unwrap_or(1f64);
match request.metadata {
Some(ref metadata) => (metadata.width as f64 / pixel_density) as u32,
None => 0,
}
}
// https://html.spec.whatwg.org/multipage/#dom-img-naturalheight
fn NaturalHeight(&self) -> u32 {
let request = self.current_request.borrow();
let pixel_density = request.current_pixel_density.unwrap_or(1f64);
match request.metadata {
Some(ref metadata) => (metadata.height as f64 / pixel_density) as u32,
None => 0,
}
}
// https://html.spec.whatwg.org/multipage/#dom-img-complete
fn Complete(&self) -> bool {
let elem = self.upcast::<Element>();
// TODO: take srcset into account
if !elem.has_attribute(&local_name!("src")) {
return true
}
let src = elem.get_string_attribute(&local_name!("src"));
if src.is_empty() {
return true
}
let request = self.current_request.borrow();
let request_state = request.state;
match request_state {
State::CompletelyAvailable | State::Broken => return true,
State::PartiallyAvailable | State::Unavailable => return false,
}
}
// https://html.spec.whatwg.org/multipage/#dom-img-currentsrc
fn CurrentSrc(&self) -> DOMString {
let current_request = self.current_request.borrow();
let ref url = current_request.parsed_url;
match *url {
Some(ref url) => DOMString::from_string(url.clone().into_string()),
None => {
let ref unparsed_url = current_request.source_url;
match *unparsed_url {
Some(ref url) => url.clone(),
None => DOMString::from("")
}
},
}
}
// https://html.spec.whatwg.org/multipage/#dom-img-name
make_getter!(Name, "name");
// https://html.spec.whatwg.org/multipage/#dom-img-name
make_atomic_setter!(SetName, "name");
// https://html.spec.whatwg.org/multipage/#dom-img-align
make_getter!(Align, "align");
// https://html.spec.whatwg.org/multipage/#dom-img-align
make_setter!(SetAlign, "align");
// https://html.spec.whatwg.org/multipage/#dom-img-hspace
make_uint_getter!(Hspace, "hspace");
// https://html.spec.whatwg.org/multipage/#dom-img-hspace
make_uint_setter!(SetHspace, "hspace");
// https://html.spec.whatwg.org/multipage/#dom-img-vspace
make_uint_getter!(Vspace, "vspace");
// https://html.spec.whatwg.org/multipage/#dom-img-vspace
make_uint_setter!(SetVspace, "vspace");
// https://html.spec.whatwg.org/multipage/#dom-img-longdesc
make_getter!(LongDesc, "longdesc");
// https://html.spec.whatwg.org/multipage/#dom-img-longdesc
make_setter!(SetLongDesc, "longdesc");
// https://html.spec.whatwg.org/multipage/#dom-img-border
make_getter!(Border, "border");
// https://html.spec.whatwg.org/multipage/#dom-img-border
make_setter!(SetBorder, "border");
}
impl VirtualMethods for HTMLImageElement {
fn super_type(&self) -> Option<&VirtualMethods> {
Some(self.upcast::<HTMLElement>() as &VirtualMethods)
}
fn adopting_steps(&self, old_doc: &Document) {
self.super_type().unwrap().adopting_steps(old_doc);
self.update_the_image_data();
}
fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
self.super_type().unwrap().attribute_mutated(attr, mutation);
match attr.local_name() {
&local_name!("src") => self.update_the_image_data(),
&local_name!("srcset") => self.update_the_image_data(),
_ => {},
}
if let Some(parent) = self.upcast::<Node>().GetParentElement() {
if parent.is::<HTMLPictureElement>() {
self.update_the_image_data();
}
}
}
fn parse_plain_attribute(&self, name: &LocalName, value: DOMString) -> AttrValue {
match name {
&local_name!("name") => AttrValue::from_atomic(value.into()),
&local_name!("width") | &local_name!("height") => AttrValue::from_dimension(value.into()),
&local_name!("hspace") | &local_name!("vspace") => AttrValue::from_u32(value.into(), 0),
_ => self.super_type().unwrap().parse_plain_attribute(name, value),
}
}
fn handle_event(&self, event: &Event) {
if event.type_() != atom!("click") {
return
}
let area_elements = self.areas();
let elements = match area_elements {
Some(x) => x,
None => return,
};
// Fetch click coordinates
let mouse_event = match event.downcast::<MouseEvent>() {
Some(x) => x,
None => return,
};
let point = Point2D::new(mouse_event.ClientX().to_f32().unwrap(),
mouse_event.ClientY().to_f32().unwrap());
let bcr = self.upcast::<Element>().GetBoundingClientRect();
let bcr_p = Point2D::new(bcr.X() as f32, bcr.Y() as f32);
// Walk HTMLAreaElements
for element in elements {
let shape = element.get_shape_from_coords();
let shp = match shape {
Some(x) => x.absolute_coords(bcr_p),
None => return,
};
if shp.hit_test(&point) {
element.activation_behavior(event, self.upcast());
return
}
}
}
fn bind_to_tree(&self, tree_in_doc: bool) {
if let Some(ref s) = self.super_type() {
s.bind_to_tree(tree_in_doc);
}
let document = document_from_node(self);
if tree_in_doc {
document.register_responsive_image(self);
}
if let Some(parent) = self.upcast::<Node>().GetParentElement() {
if parent.is::<HTMLPictureElement>() {
self.update_the_image_data();
}
}
}
fn unbind_from_tree(&self, context: &UnbindContext) {
self.super_type().unwrap().unbind_from_tree(context);
let document = document_from_node(self);
document.unregister_responsive_image(self);
}
}
impl FormControl for HTMLImageElement {
fn form_owner(&self) -> Option<DomRoot<HTMLFormElement>> {
self.form_owner.get()
}
fn set_form_owner(&self, form: Option<&HTMLFormElement>) {
self.form_owner.set(form);
}
fn to_element<'a>(&'a self) -> &'a Element {
self.upcast::<Element>()
}
fn is_listed(&self) -> bool {
false
}
}
fn image_dimension_setter(element: &Element, attr: LocalName, value: u32) {
// This setter is a bit weird: the IDL type is unsigned long, but it's parsed as
// a dimension for rendering.
let value = if value > UNSIGNED_LONG_MAX {
0
} else {
value
};
// FIXME: There are probably quite a few more cases of this. This is the
// only overflow that was hitting on automation, but we should consider what
// to do in the general case case.
//
// See <https://github.com/servo/app_units/issues/22>
let pixel_value = if value > (i32::MAX / AU_PER_PX) as u32 {
0
} else {
value
};
let dim = LengthOrPercentageOrAuto::Length(Au::from_px(pixel_value as i32));
let value = AttrValue::Dimension(value.to_string(), dim);
element.set_attribute(&attr, value);
}
/// Collect sequence of code points
pub fn collect_sequence_characters<F>(s: &str, predicate: F) -> (&str, &str)
where F: Fn(&char) -> bool
{
for (i, ch) in s.chars().enumerate() {
if !predicate(&ch) {
return (&s[0..i], &s[i..])
}
}
return (s, "");
}
/// Parse an `srcset` attribute - https://html.spec.whatwg.org/multipage/#parsing-a-srcset-attribute.
pub fn parse_a_srcset_attribute(input: &str) -> Vec<ImageSource> {
let mut url_len = 0;
let mut candidates: Vec<ImageSource> = vec![];
while url_len < input.len() {
let position = &input[url_len..];
let (spaces, position) = collect_sequence_characters(position, |c| *c == ',' || char::is_whitespace(*c));
// add the length of the url that we parse to advance the start index
let space_len = spaces.char_indices().count();
url_len += space_len;
if position.is_empty() {
return candidates;
}
let (url, spaces) = collect_sequence_characters(position, |c| !char::is_whitespace(*c));
// add the counts of urls that we parse to advance the start index
url_len += url.chars().count();
let comma_count = url.chars().rev().take_while(|c| *c == ',').count();
let url: String = url.chars().take(url.chars().count() - comma_count).collect();
// add 1 to start index, for the comma
url_len += comma_count + 1;
let (space, position) = collect_sequence_characters(spaces, |c| char::is_whitespace(*c));
let space_len = space.len();
url_len += space_len;
let mut descriptors = Vec::new();
let mut current_descriptor = String::new();
let mut state = ParseState::InDescriptor;
let mut char_stream = position.chars().enumerate();
let mut buffered: Option<(usize, char)> = None;
loop {
let next_char = buffered.take().or_else(|| char_stream.next());
if next_char.is_some() {
url_len += 1;
}
match state {
ParseState::InDescriptor => {
match next_char {
Some((_, ' ')) => {
if !current_descriptor.is_empty() {
descriptors.push(current_descriptor.clone());
current_descriptor = String::new();
state = ParseState::AfterDescriptor;
}
continue;
}
Some((_, ',')) => {
if !current_descriptor.is_empty() {
descriptors.push(current_descriptor.clone());
}
break;
}
Some((_, c @ '(')) => {
current_descriptor.push(c);
state = ParseState::InParens;
continue;
}
Some((_, c)) => {
current_descriptor.push(c);
}
None => {
if !current_descriptor.is_empty() {
descriptors.push(current_descriptor.clone());
}
break;
}
}
}
ParseState::InParens => {
match next_char {
Some((_, c @ ')')) => {
current_descriptor.push(c);
state = ParseState::InDescriptor;
continue;
}
Some((_, c)) => {
current_descriptor.push(c);
continue;
}
None => {
if !current_descriptor.is_empty() {
descriptors.push(current_descriptor.clone());
}
break;
}
}
}
ParseState::AfterDescriptor => {
match next_char {
Some((_, ' ')) => {
state = ParseState::AfterDescriptor;
continue;
}
Some((idx, c)) => {
state = ParseState::InDescriptor;
buffered = Some((idx, c));
continue;
}
None => {
if !current_descriptor.is_empty() {
descriptors.push(current_descriptor.clone());
}
break;
}
}
}
}
}
let mut error = false;
let mut width: Option<u32> = None;
let mut density: Option<f64> = None;
let mut future_compat_h: Option<u32> = None;
for descriptor in descriptors {
let (digits, remaining) = collect_sequence_characters(&descriptor, |c| is_ascii_digit(c) || *c == '.');
let valid_non_negative_integer = parse_unsigned_integer(digits.chars());
let has_w = remaining == "w";
let valid_floating_point = parse_double(digits);
let has_x = remaining == "x";
let has_h = remaining == "h";
if valid_non_negative_integer.is_ok() && has_w {
let result = valid_non_negative_integer;
error = result.is_err();
if width.is_some() || density.is_some() {
error = true;
}
if let Ok(w) = result {
width = Some(w);
}
} else if valid_floating_point.is_ok() && has_x {
let result = valid_floating_point;
error = result.is_err();
if width.is_some() || density.is_some() || future_compat_h.is_some() {
error = true;
}
if let Ok(x) = result {
density = Some(x);
}
} else if valid_non_negative_integer.is_ok() && has_h {
let result = valid_non_negative_integer;
error = result.is_err();
if density.is_some() || future_compat_h.is_some() {
error = true;
}
if let Ok(h) = result {
future_compat_h = Some(h);
}
} else {
error = true;
}
}
if future_compat_h.is_some() && width.is_none() {
error = true;
}
if !error {
let descriptor = Descriptor { wid: width, den: density };
let image_source = ImageSource { url: url, descriptor: descriptor };
candidates.push(image_source);
}
}
candidates
}
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