script: Make the resource task communication use IPC channels.
This change makes Servo use serialized messages over IPC channels for resource loading. The goal is to make it easier to make Servo multiprocess in the future. This patch does not make Servo multiprocess now; there are many other channels that need to be changed to IPC before that can happen. It does introduce a dependency on https://github.com/serde-rs/serde and https://github.com/pcwalton/ipc-channel for the first time.
At the moment, `ipc-channel` uses JSON for serialization. This is because serde does not yet have official support for bincode. When serde gains support for bincode, I'll switch to that. For now, however, the JSON encoding and decoding will constitute a significant performance regression in resource loading.
To avoid having to send boxed `AsyncResponseTarget` trait objects across process boundaries, this series of commits changes `AsyncResponseTarget` to wrap a sender only. It is then the client's responsibility to spawn a thread to proxy calls from that sender to the consumer of the resource data. This only had to be done in a few places. In the future, we may want to collapse those threads into one per process to reduce overhead. (It is impossible to continue to use `AsyncResponseTarget` as a boxed trait object across processes, regardless of how much work is done on `ipc-channel`. Vtables are fundamentally incompatible with IPC across mutually untrusting processes.)
In general, I was pretty pleased with how this turned out. The main changes are adding serialization functionality to various objects that `serde` does not know how to serialize natively—the most complicated being Hyper objects—and reworking `AsyncResponseTarget`. The overall structure of the code is unchanged, and other than `AsyncResponseTarget` no functionality was lost in moving to serialization and IPC.
r? @jdm
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Use local slice_chars
StrExt::slice_chars is deprecated and will be removed in Rust. This
lifts the implementation from Rust libstd and puts it in util::str.
This fixes a bunch of deprecation warnings in Servo.
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StrExt::slice_chars is deprecated and will be removed in Rust. This
lifts the implementation from Rust libstd and puts it in util::str.
This fixes a bunch of deprecation warnings in Servo.
Implement Msg::Status with serialized url upon mouseover
Credits for Mike Blumenkrantz (@zmike), I just rebased against trunk and
fixed the url serialization.
Fixes#6178.
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Implement ChildNode::before & ChildNode::after
Continued from #6536
The current implementations of `ChildNode::before` and
`ChildNode::after` do not match the WHATWG spec. This commit updates the
implementations to match the spec.
Our current implementation of `ChildNode::after` passes all the WPT
tests. So I made sure to add a regression test that failed with the
current implementation. There are a few other unit tests I added
to exhaust other corner cases I encountered.
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script: Squash duplicate animation tick events in the queue.
This prevents them from piling up endlessly if the JS
`requestAnimationFrame()` callback takes a long time to complete.
r? @jdm
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Add a `kind` field to memory reports.
This is used for two memory reporting improvements.
- It's used to distinguish "explicit" memory reports from others. This
mirrors the same categorization that is used in Firefox, and gives a single
tree that's the best place to look. It replaces the "pages" tree which
was always intended to be a temporary stand-in for "explicit".
- It's used to computed "heap-unclassified" values for both the jemalloc
and system heaps, both of which are placed into the "explicit" tree.
Example output:
```
| 114.99 MiB -- explicit
| 52.34 MiB -- jemalloc-heap-unclassified
| 46.14 MiB -- system-heap-unclassified
| 14.95 MiB -- url(file:///home/njn/moz/servo2/../servo-static-suite/wikipe
dia/Guardians%20of%20the%20Galaxy%20(film)%20-%20Wikipedia,%20the%20free%20encyc
lopedia.html)
| 7.32 MiB -- js
| 3.07 MiB -- malloc-heap
| 3.00 MiB -- gc-heap
| 2.49 MiB -- used
| 0.34 MiB -- decommitted
| 0.09 MiB -- unused
| 0.09 MiB -- admin
| 1.25 MiB -- non-heap
| 1.36 MiB -- layout-worker-3-local-context
| 1.34 MiB -- layout-worker-0-local-context
| 1.24 MiB -- layout-worker-1-local-context
| 1.24 MiB -- layout-worker-4-local-context
| 1.16 MiB -- layout-worker-2-local-context
| 0.89 MiB -- layout-worker-5-local-context
| 0.38 MiB -- layout-task
| 0.31 MiB -- display-list
| 0.07 MiB -- local-context
| 1.56 MiB -- compositor-task
| 0.78 MiB -- surface-map
| 0.78 MiB -- layer-tree
```
The heap-unclassified values dominate the "explicit" tree because reporter
coverage is still quite poor.
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Implement getComputedStyle
It's not quite done but can probably be reviewed anyway.
I still need to finish up a few of the ToCss impls, I just got lazy and wanted to make sure things worked.
The computation of the used values is definitely not right, I'm going to investigate that.
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This is used for two memory reporting improvements.
- It's used to distinguish "explicit" memory reports from others. This
mirrors the same categorization that is used in Firefox, and gives a single
tree that's the best place to look. It replaces the "pages" tree which
was always intended to be a temporary stand-in for "explicit".
- It's used to computed "heap-unclassified" values for both the jemalloc
and system heaps, both of which are placed into the "explicit" tree.
Example output:
```
| 114.99 MiB -- explicit
| 52.34 MiB -- jemalloc-heap-unclassified
| 46.14 MiB -- system-heap-unclassified
| 14.95 MiB -- url(file:///home/njn/moz/servo2/../servo-static-suite/wikipe
dia/Guardians%20of%20the%20Galaxy%20(film)%20-%20Wikipedia,%20the%20free%20encyc
lopedia.html)
| 7.32 MiB -- js
| 3.07 MiB -- malloc-heap
| 3.00 MiB -- gc-heap
| 2.49 MiB -- used
| 0.34 MiB -- decommitted
| 0.09 MiB -- unused
| 0.09 MiB -- admin
| 1.25 MiB -- non-heap
| 1.36 MiB -- layout-worker-3-local-context
| 1.34 MiB -- layout-worker-0-local-context
| 1.24 MiB -- layout-worker-1-local-context
| 1.24 MiB -- layout-worker-4-local-context
| 1.16 MiB -- layout-worker-2-local-context
| 0.89 MiB -- layout-worker-5-local-context
| 0.38 MiB -- layout-task
| 0.31 MiB -- display-list
| 0.07 MiB -- local-context
| 1.56 MiB -- compositor-task
| 0.78 MiB -- surface-map
| 0.78 MiB -- layer-tree
```
The heap-unclassified values dominate the "explicit" tree because reporter
coverage is still quite poor.
Dispose layout data for every node removed from the tree
Fix for #6754.
cc @jdm – I believe this is all that's required for the fix, but until I get a better sense of #6813, I'm unsure of the best way to test this.
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Continued from #6536
The current implementations of `ChildNode::before` and
`ChildNode::after` do not match the WHATWG spec. This commit updates the
implementations to match the spec.
Our current implementation of `ChildNode::after` passes all the WPT
tests. So I made sure to add a regression test that failed with the
current implementation. There are a few other unit tests I added
to exhaust other corner cases I encountered.
