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Code Issues Projects Releases Wiki Activity

Update some broken anchor links (#1444)

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Philipp Oppermann
2025-12-08 17:31:52 +01:00
committed by GitHub
parent 86c36479cf
commit 211f460251
56 changed files with 387 additions and 387 deletions
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blog/content/edition-2/posts/07-hardware-interrupts/index.md
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@@ -274,16 +274,16 @@ pub fn _print(args: fmt::Arguments) {
It locks the `WRITER`, calls `write_fmt` on it, and implicitly unlocks it at the end of the function. Now imagine that an interrupt occurs while the `WRITER` is locked and the interrupt handler tries to print something too:
Timestep | _start | interrupt_handler
---------|------|------------------
0 | calls `println!` |  
1 | `print` locks `WRITER` |  
2 | | **interrupt occurs**, handler begins to run
3 | | calls `println!` |
4 | | `print` tries to lock `WRITER` (already locked)
5 | | `print` tries to lock `WRITER` (already locked)
… | | …
_never_ | _unlock `WRITER`_ |
| Timestep | _start | interrupt_handler |
| -------- | ---------------------- | ----------------------------------------------- |
| 0 | calls `println!` |   |
| 1 | `print` locks `WRITER` |   |
| 2 | | **interrupt occurs**, handler begins to run |
| 3 | | calls `println!` |
| 4 | | `print` tries to lock `WRITER` (already locked) |
| 5 | | `print` tries to lock `WRITER` (already locked) |
| … | | … |
| _never_ | _unlock `WRITER`_ |
The `WRITER` is locked, so the interrupt handler waits until it becomes free. But this never happens, because the `_start` function only continues to run after the interrupt handler returns. Thus, the entire system hangs.
@@ -640,7 +640,7 @@ extern "x86-interrupt" fn keyboard_interrupt_handler(
The above code translates keypresses of the number keys 0-9 and ignores all other keys. It uses a [match] statement to assign a character or `None` to each scancode. It then uses [`if let`] to destructure the optional `key`. By using the same variable name `key` in the pattern, we [shadow] the previous declaration, which is a common pattern for destructuring `Option` types in Rust.
[match]: https://doc.rust-lang.org/book/ch06-02-match.html
[`if let`]: https://doc.rust-lang.org/book/ch18-01-all-the-places-for-patterns.html#conditional-if-let-expressions
[`if let`]: https://doc.rust-lang.org/book/ch19-01-all-the-places-for-patterns.html#conditional-if-let-expressions
[shadow]: https://doc.rust-lang.org/book/ch03-01-variables-and-mutability.html#shadowing
Now we can write numbers: