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Fix lot of dead links in both the 2nd and 1st edition

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Philipp Oppermann
2019-07-07 10:33:12 +02:00
parent 265f9f9bd5
commit bc5631d9a8
30 changed files with 146 additions and 153 deletions
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blog/content/first-edition/posts/08-kernel-heap/index.md
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@@ -24,9 +24,9 @@ As always, you can find the complete source code on [GitHub]. Please file [issue
## Introduction
The _heap_ is the memory area for long-lived allocations. The programmer can access it by using types like [Box][Box rustbyexample] or [Vec]. Behind the scenes, the compiler manages that memory by inserting calls to some memory allocator. By default, Rust links to the [jemalloc] allocator (for binaries) or the system allocator (for libraries). However, both rely on [system calls] such as [sbrk] and are thus unusable in our kernel. So we need to create and link our own allocator.
[Box rustbyexample]: http://rustbyexample.com/std/box.html
[Box rustbyexample]: https://doc.rust-lang.org/rust-by-example/std/box.html
[Vec]: https://doc.rust-lang.org/book/vectors.html
[jemalloc]: http://www.canonware.com/jemalloc/
[jemalloc]: http://jemalloc.net/
[system calls]: https://en.wikipedia.org/wiki/System_call
[sbrk]: https://en.wikipedia.org/wiki/Sbrk
@@ -42,7 +42,7 @@ These requirements make good allocators pretty complex. For example, [jemalloc]
The allocator interface in Rust is defined through the [`Alloc` trait], which looks like this:
[`Alloc` trait]: https://doc.rust-lang.org/nightly/alloc/allocator/trait.Alloc.html
[`Alloc` trait]: https://doc.rust-lang.org/1.20.0/alloc/allocator/trait.Alloc.html
```rust
pub unsafe trait Alloc {
@@ -87,8 +87,8 @@ extern crate alloc;
We don't need to add anything to our Cargo.toml, since the `alloc` crate is part of the standard library and shipped with the Rust compiler. The `alloc` crate provides the [format!] and [vec!] macros, so we use `#[macro_use]` to import them.
[format!]: //doc.rust-lang.org/nightly/collections/macro.format!.html
[vec!]: https://doc.rust-lang.org/nightly/collections/macro.vec!.html
[format!]: https://doc.rust-lang.org/1.10.0/collections/macro.format!.html
[vec!]: https://doc.rust-lang.org/1.10.0/collections/macro.vec!.html
When we try to compile our crate now, the following error occurs:
@@ -573,14 +573,14 @@ We can also use all other types of the `alloc` crate, including:
- [BinaryHeap]
- [BTreeMap] and [BTreeSet]
[Rc]: https://doc.rust-lang.org/nightly/alloc/rc/
[Arc]: https://doc.rust-lang.org/nightly/alloc/arc/
[String]: https://doc.rust-lang.org/nightly/collections/string/struct.String.html
[Linked List]: https://doc.rust-lang.org/nightly/collections/linked_list/struct.LinkedList.html
[VecDeque]: https://doc.rust-lang.org/nightly/collections/vec_deque/struct.VecDeque.html
[BinaryHeap]: https://doc.rust-lang.org/nightly/collections/binary_heap/struct.BinaryHeap.html
[BTreeMap]: https://doc.rust-lang.org/nightly/collections/btree_map/struct.BTreeMap.html
[BTreeSet]: https://doc.rust-lang.org/nightly/collections/btree_set/struct.BTreeSet.html
[Rc]: https://doc.rust-lang.org/1.10.0/alloc/rc/
[Arc]: https://doc.rust-lang.org/1.10.0/alloc/arc/
[String]: https://doc.rust-lang.org/1.10.0/collections/string/struct.String.html
[Linked List]: https://doc.rust-lang.org/1.10.0/collections/linked_list/struct.LinkedList.html
[VecDeque]: https://doc.rust-lang.org/1.10.0/collections/vec_deque/struct.VecDeque.html
[BinaryHeap]: https://doc.rust-lang.org/1.10.0/collections/binary_heap/struct.BinaryHeap.html
[BTreeMap]: https://doc.rust-lang.org/1.10.0/collections/btree_map/struct.BTreeMap.html
[BTreeSet]: https://doc.rust-lang.org/1.10.0/collections/btree_set/struct.BTreeSet.html
## A better Allocator
Right now, we leak every freed memory block. Thus, we run out of memory quickly, for example, by creating a new `String` in each iteration of a loop: