servo/components/script/dom/bindings/num.rs
Nicholas Nethercote 4506f0d30c Replace all uses of the heapsize crate with malloc_size_of.
Servo currently uses `heapsize`, but Stylo/Gecko use `malloc_size_of`.
`malloc_size_of` is better -- it handles various cases that `heapsize` does not
-- so this patch changes Servo to use `malloc_size_of`.

This patch makes the following changes to the `malloc_size_of` crate.

- Adds `MallocSizeOf` trait implementations for numerous types, some built-in
  (e.g. `VecDeque`), some external and Servo-only (e.g. `string_cache`).

- Makes `enclosing_size_of_op` optional, because vanilla jemalloc doesn't
  support that operation.

- For `HashSet`/`HashMap`, falls back to a computed estimate when
  `enclosing_size_of_op` isn't available.

- Adds an extern "C" `malloc_size_of` function that does the actual heap
  measurement; this is based on the same functions from the `heapsize` crate.

This patch makes the following changes elsewhere.

- Converts all the uses of `heapsize` to instead use `malloc_size_of`.

- Disables the "heapsize"/"heap_size" feature for the external crates that
  provide it.

- Removes the `HeapSizeOf` implementation from `hashglobe`.

- Adds `ignore` annotations to a few `Rc`/`Arc`, because `malloc_size_of`
  doesn't derive those types, unlike `heapsize`.
2017-10-18 22:20:37 +11:00

54 lines
1.4 KiB
Rust

/* 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/. */
//! The `Finite<T>` struct.
use malloc_size_of::{MallocSizeOf, MallocSizeOfOps};
use num_traits::Float;
use std::default::Default;
use std::ops::Deref;
/// Encapsulates the IDL restricted float type.
#[derive(Clone, Copy, Eq, JSTraceable, PartialEq)]
pub struct Finite<T: Float>(T);
impl<T: Float> Finite<T> {
/// Create a new `Finite<T: Float>` safely.
pub fn new(value: T) -> Option<Finite<T>> {
if value.is_finite() {
Some(Finite(value))
} else {
None
}
}
/// Create a new `Finite<T: Float>`.
#[inline]
pub fn wrap(value: T) -> Finite<T> {
assert!(value.is_finite(),
"Finite<T> doesn't encapsulate unrestricted value.");
Finite(value)
}
}
impl<T: Float> Deref for Finite<T> {
type Target = T;
fn deref(&self) -> &T {
let &Finite(ref value) = self;
value
}
}
impl<T: Float + MallocSizeOf> MallocSizeOf for Finite<T> {
fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize {
(**self).size_of(ops)
}
}
impl<T: Float + Default> Default for Finite<T> {
fn default() -> Finite<T> {
Finite::wrap(T::default())
}
}