Implement `ByteStr` and `ByteString` types
Approved ACP: https://github.com/rust-lang/libs-team/issues/502
Tracking issue: https://github.com/rust-lang/rust/issues/134915
These types represent human-readable strings that are conventionally,
but not always, UTF-8. The `Debug` impl prints non-UTF-8 bytes using
escape sequences, and the `Display` impl uses the Unicode replacement
character.
This is a minimal implementation of these types and associated trait
impls. It does not add any helper methods to other types such as `[u8]`
or `Vec<u8>`.
I've omitted a few implementations of `AsRef`, `AsMut`, and `Borrow`,
when those would be the second implementation for a type (counting the
`T` impl), to avoid potential inference failures. We can attempt to add
more impls later in standalone commits, and run them through crater.
In addition to the `bstr` feature, I've added a `bstr_internals` feature
for APIs provided by `core` for use by `alloc` but not currently
intended for stabilization.
This API and its implementation are based *heavily* on the `bstr` crate
by Andrew Gallant (`@BurntSushi).`
r? `@BurntSushi`
doc: Point to methods on `Command` as alternatives to `set/remove_var`
Make these methods more discoverable, as configuring a child process is a common reason for manipulating the environment.
Remove dead rustc_allowed_through_unstable_modules for std::os::fd contents
As far as I was able to reconstruct, the history here is roughly as follows:
- https://github.com/rust-lang/rust/pull/99723 added some `rustc_allowed_through_unstable_modules` to the types in `std::os::fd::raw` since they were accessible on stable via the unstable `std::os::wasi::io::AsRawFd` path. (This was needed to fix https://github.com/rust-lang/rust/issues/99502.)
- Shortly thereafter, https://github.com/rust-lang/rust/pull/98368 re-organized things so that instead of re-exporting from an internal `std::os::wasi::io::raw`, `std::os::wasi::io::AsRawFd` is now directly re-exported from `std::os::fd`. This also made `library/std/src/os/wasi/io/raw.rs` entirely dead code as far as I can tell, it's not imported by anything any more.
- Shortly thereafter, https://github.com/rust-lang/rust/pull/103308 stabilizes `std::os::wasi::io`, so `rustc_allowed_through_unstable_modules` is not needed any more to access `std::os::wasi::io::AsRawFd`. There is even a comment in `library/std/src/os/wasi/io/raw.rs` saying the attribute can be removed now, but that file is dead code so it is not touched as part of the stabilization.
I did a grep for `pub use crate::os::fd` and all the re-exports I could find are in stable modules. So given all that, we can remove the `rustc_allowed_through_unstable_modules` (hoping they are not also re-exported somewhere else, it's really hard to be sure about this).
I have checked that std still builds after this PR on the wasm32-wasip2 target.
Clarify note in `std::sync::LazyLock` example
I doubt most people know what it means, as I did not until a week ago. In the current form, it seems like a `TODO:`.
std: lazily allocate the main thread handle
https://github.com/rust-lang/rust/pull/123550 eliminated the allocation of the main thread handle, but at the cost of greatly increased complexity. This PR proposes another approach: Instead of creating the main thread handle itself, the runtime simply remembers the thread ID of the main thread. The main thread handle is then only allocated when it is used, using the same lazy-initialization mechanism as for non-runtime use of `thread::current`, and the `name` method uses the thread ID to identify the main thread handle and return the correct name ("main") for it.
Thereby, we also allow accessing `thread::current` before main: as the runtime no longer tries to install its own handle, this will no longer trigger an abort. Rather, the name returned from `name` will only be "main" after the runtime initialization code has run, but I think that is acceptable.
This new approach also requires some changes to the signal handling code, as calling `thread::current` would now allocate when called on the main thread, which is not acceptable. I fixed this by adding a new function (`with_current_name`) that performs all the naming logic without allocation or without initializing the thread ID (which could allocate on some platforms).
Reverts #123550, CC ``@GnomedDev``
Also, the macro is only called three times, and all with the same local variable entry_ptr, so just use the local variable directly,
and rename the macro to entry_field_ptr.
Thereby, we also allow accessing thread::current before main: as the runtime no longer tries to install its own handle, this will no longer trigger an abort. Rather, the name returned from name will only be "main" after the runtime initialization code has run, but I think that is acceptable.
This new approach also requires some changes to the signal handling code, as calling `thread::current` would now allocate when called on the main thread, which is not acceptable. I fixed this by adding a new function (`with_current_name`) that performs all the naming logic without allocation or without initializing the thread ID (which could allocate on some platforms).
use a single large catch_unwind in lang_start
I originally planned to use `abort_unwind` but reading the comment in `thread_cleanup` it seems we are deliberately going for slightly nicer error messages here, so this preserves that. It still seems nice to not repeat `catch_unwind` so often.
uefi: helpers: Introduce OwnedDevicePath
This PR is split off from #135368 to reduce noise.
No real functionality changes, just some quality of life improvements.
Also implement Debug for OwnedDevicePath for some quality of life
improvements.
This PR is split off from #135368 to reduce noise.
Rename DevicePath to OwnedDevicePath. This is to allow a non-owning
version of DevicePath in the future to work with UEFI shell APIs which
provide const pointers to device paths for UEFI shell fs mapping.
Also implement Debug for OwnedDevicePath for some quality of life
improvements.
Signed-off-by: Ayush Singh <ayush@beagleboard.org>
path: Move is_absolute check to sys::path
I am working on fs support for UEFI [0], which similar to windows has prefix components, but is not quite same as Windows. It also seems that Prefix is tied closely to Windows and cannot really be extended [1].
This PR just tries to remove coupling between Prefix and absolute path checking to allow platforms to provide there own implementation to check if a path is absolute or not.
I am not sure if any platform other than windows currently uses Prefix, so I have kept the path.prefix().is_some() check in most cases.
[0]: https://github.com/rust-lang/rust/pull/135368
[1]: https://github.com/rust-lang/rust/issues/52331#issuecomment-2492796137
I am working on fs support for UEFI [0], which similar to windows has prefix
components, but is not quite same as Windows. It also seems that Prefix
is tied closely to Windows and cannot really be extended [1].
This PR just tries to remove coupling between Prefix and absolute path
checking to allow platforms to provide there own implementation to check
if a path is absolute or not.
I am not sure if any platform other than windows currently uses Prefix,
so I have kept the path.prefix().is_some() check in most cases.
[0]: https://github.com/rust-lang/rust/pull/135368
[1]: https://github.com/rust-lang/rust/issues/52331#issuecomment-2492796137
Signed-off-by: Ayush Singh <ayush@beagleboard.org>
Use `NonNull::without_provenance` within the standard library
This API removes the need for several `unsafe` blocks, and leads to clearer code. It uses feature `nonnull_provenance` (#135243).
Close#135343
Initial fs module for uefi
- Just a copy of unsupported fs right now to reduce the noise from future PRs to allow for easier review.
- For the full working version of fs on uefi, see [0]
- This is an effort to break the original PR (#129700) into much smaller chunks for faster upstreaming.
[0]: https://github.com/Ayush1325/rust/tree/uefi-file-full
Update a bunch of library types for MCP807
This greatly reduces the number of places that actually use the `rustc_layout_scalar_valid_range_*` attributes down to just 3:
```
library/core\src\ptr\non_null.rs
68:#[rustc_layout_scalar_valid_range_start(1)]
library/core\src\num\niche_types.rs
19: #[rustc_layout_scalar_valid_range_start($low)]
20: #[rustc_layout_scalar_valid_range_end($high)]
```
Everything else -- PAL Nanoseconds, alloc's `Cap`, niched FDs, etc -- all just wrap those `niche_types` types.
r? ghost
Approved ACP: https://github.com/rust-lang/libs-team/issues/502
Tracking issue: https://github.com/rust-lang/rust/issues/134915
These types represent human-readable strings that are conventionally,
but not always, UTF-8. The `Debug` impl prints non-UTF-8 bytes using
escape sequences, and the `Display` impl uses the Unicode replacement
character.
This is a minimal implementation of these types and associated trait
impls. It does not add any helper methods to other types such as `[u8]`
or `Vec<u8>`.
I've omitted a few implementations of `AsRef`, `AsMut`, `Borrow`,
`From`, and `PartialOrd`, when those would be the second implementation
for a type (counting the `T` impl) or otherwise may cause inference
failures. These impls are important, but we can attempt to add them
later in standalone commits, and run them through crater.
In addition to the `bstr` feature, I've added a `bstr_internals` feature
for APIs provided by `core` for use by `alloc` but not currently
intended for stabilization.
This API and its implementation are based *heavily* on the `bstr` crate
by Andrew Gallant (@BurntSushi).
Used pthread name functions returning result for FreeBSD and DragonFly
`pthread_getname_np` and `pthread_setname_np` received a wider adoption in past years and was added to:
* FreeBSD by June 11 2020 via [`2ef84b7da9a6c3e23b4a135e6e863581f16d46e1`](2ef84b7da9),
* DargonFly by March 8 2021 via [`ab5dc9aceb34419d1c4b6006739e61acee8ee999`](https://gitweb.dragonflybsd.org/dragonfly.git/commitdiff/ab5dc9aceb34419d1c4b6006739e61acee8ee999).
There's not so much advantage except that the result can be checked in debug builds. Ideally it should be unified with Linux' implementation, but it trims the input.
This greatly reduces the number of places that actually use the `rustc_layout_scalar_valid_range_*` attributes down to just 3:
```
library/core\src\ptr\non_null.rs
68:#[rustc_layout_scalar_valid_range_start(1)]
library/core\src\num\niche_types.rs
19: #[rustc_layout_scalar_valid_range_start($low)]
20: #[rustc_layout_scalar_valid_range_end($high)]
```
Everything else -- PAL Nanoseconds, alloc's `Cap`, niched FDs, etc -- all just wrap those `niche_types` types.
- Just a copy of unsupported fs right now to reduce the noise from
future PRs to allow for easier review.
- For the full working version of fs on uefi, see [0]
[0]: https://github.com/Ayush1325/rust/tree/uefi-file-full
Signed-off-by: Ayush Singh <ayush@beagleboard.org>
