Implement default methods for `io::Empty` and `io::Sink`
Implements default methods of `io::Read`, `io::BufRead`, and `io::Write` for `io::Empty` and `io::Sink`. These implementations are equivalent to the defaults, except in doing less unnecessary work.
`Read::read_to_string` and `BufRead::read_line` both have a redundant call to `str::from_utf8` which can't be inlined from `core` and `Write::write_all_vectored` has slicing logic which can't be simplified (See on [Compiler Explorer](https://rust.godbolt.org/z/KK6xcrWr4)). The rest are optimized to the minimal with `-C opt-level=3`, but this PR gives that benefit to unoptimized builds.
This includes an implementation of `Write::write_fmt` which just ignores the `fmt::Arguments<'_>`. This could be problematic whenever a user formatting impl is impure, but the docs do not guarantee that the args will be expanded.
Tracked in https://github.com/rust-lang/rust/issues/136756.
r? `@m-ou-se`
`MaybeUninit` inherent slice methods part 2
These were moved out of #129259 since they require additional libs-api approval. Tracking issue: #117428.
New API surface:
```rust
impl<T> [MaybeUninit<T>] {
// replacing fill; renamed to avoid conflict
pub fn write_filled(&mut self, value: T) -> &mut [T] where T: Clone;
// replacing fill_with; renamed to avoid conflict
pub fn write_with<F>(&mut self, value: F) -> &mut [T] where F: FnMut() -> T;
// renamed to remove "fill" terminology, since this is closer to the write_*_of_slice methods
pub fn write_iter<I>(&mut self, iter: I) -> (&mut [T], &mut Self) where I: Iterator<Item = T>;
}
```
Relevant motivation for these methods; see #129259 for earlier methods' motiviations.
* I chose `write_filled` since `filled` is being used as an object here, whereas it's being used as an action in `fill`.
* I chose `write_with` instead of `write_filled_with` since it's shorter and still matches well.
* I chose `write_iter` because it feels completely different from the fill methods, and still has the intent clear.
In all of the methods, it felt appropriate to ensure that they contained `write` to clarify that they are effectively just special ways of doing `MaybeUninit::write` for each element of a slice.
Tracking issue: https://github.com/rust-lang/rust/issues/117428
r? libs-api
- Since there is no direct mkdir in UEFI, first check if a file/dir with
same path exists and then create the directory.
Signed-off-by: Ayush Singh <ayush@beagleboard.org>
Implement `read_buf` for Hermit
Following https://github.com/hermit-os/kernel/pull/1606, it is now safe to implement `Read::read_buf` for file descriptors on Hermit.
cc ```@mkroening```
uefi: fs: Implement exists
Also adds the initial file abstractions.
The file opening algorithm is inspired from UEFI shell. It starts by classifying if the Path is Shell mapping, text representation of device path protocol, or a relative path and converts into an absolute text representation of device path protocol.
After that, it queries all handles supporting
EFI_SIMPLE_FILE_SYSTEM_PROTOCOL and opens the volume that matches the device path protocol prefix (similar to Windows drive). After that, it opens the file in the volume using the remaining pat.
It also introduces OwnedDevicePath and BorrowedDevicePath abstractions to allow working with the base UEFI and Shell device paths efficiently.
DevicePath in UEFI behaves like an a group of nodes laied out in the memory contiguously and thus can be modeled using iterators.
This is an effort to break the original PR (https://github.com/rust-lang/rust/pull/129700) into much smaller chunks for faster upstreaming.
When the formatting args to `fmt::Write::write_fmt` are a statically
known string, it simplifies to only calling `write_str` without a
runtime branch. Do the same in `io::Write::write_fmt` with `write_all`.
Also, match the convention of `fmt::Write` for the name of `args`.
Also adds the initial file abstractions.
The file opening algorithm is inspired from UEFI shell. It starts by
classifying if the Path is Shell mapping, text representation of device
path protocol, or a relative path and converts into an absolute text
representation of device path protocol.
After that, it queries all handles supporting
EFI_SIMPLE_FILE_SYSTEM_PROTOCOL and opens the volume that matches the
device path protocol prefix (similar to Windows drive). After that, it
opens the file in the volume using the remaining pat.
It also introduces OwnedDevicePath and BorrowedDevicePath abstractions
to allow working with the base UEFI and Shell device paths efficiently.
DevicePath in UEFI behaves like an a group of nodes laied out in the
memory contiguously and thus can be modeled using iterators.
Signed-off-by: Ayush Singh <ayush@beagleboard.org>
In #108326, `read_buf` was implemented for a variety of types, but SGX
was saved for later. Update a test from then, now that #137355
implemented it for SGX types.
Make `_Unwind_Action` a type alias, not enum
It's bitflags in practice, so an enum is unsound, as an enum must only have the described values. The x86_64 psABI declares it as a `typedef int _Unwind_Action`, which seems reasonable. I made a newtype first but that was more annoying than just a typedef. We don't really use this value for much other than a short check.
I ran `x check library --target aarch64-unknown-linux-gnu,x86_64-pc-windows-gnu,x86_64-fortanix-unknown-sgx,x86_64-unknown-haiku,x86_64-unknown-fuchsi
a,x86_64-unknown-freebsd,x86_64-unknown-dragonfly,x86_64-unknown-netbsd,x86_64-unknown-openbsd,x86_64-unknown-redox,riscv64-linux-android,armv7-unknown-freebsd` (and some more but they failed to build for other reasons :D)
fixes#138558
r? workingjubilee have fun
It's bitflags in practice, so an enum is unsound, as an enum must only
have the described values. The x86_64 psABI declares it as a `typedef
int _Unwind_Action`, which seems reasonable. I made a newtype first but
that was more annoying than just a typedef. We don't really use this
value for much other than a short check.
- Events are going to become quite important for Networking, so needed
owned abstractions.
- Switch to OwnedEvent abstraction for Exit boot services event.
Signed-off-by: Ayush Singh <ayush@beagleboard.org>
uefi: helpers: Add DevicePathNode abstractions
- UEFI device path is a series of nodes layed out in a contiguous memory region. So it makes sense to use Iterator abstraction for modeling DevicePaths
- This PR has been split off from #135368 for easier review. The allow dead_code will be removed in #135368
cc `@nicholasbishop`
Remove usage of legacy scheme paths on RedoxOS
The `name:/path` path syntax is getting phased out[^1] in favor of `/scheme/name/path`. Also using `null:` is no longer necessary as `/dev/null` is available on Redox OS too.
[^1]: https://gitlab.redox-os.org/redox-os/rfcs/-/blob/master/text/0006-scheme-path.md
cc `@jackpot51`
Improve HashMap docs for const and static initializers
Closes#137566.
I clarified the HashMap usage in const and static initializers.
I also added examples of how to construct such HashMaps wrapped in LazyLock.
The name:/path path syntax is getting phased out in favor of
/scheme/name/path. Also using null: is no longer necessary as /dev/null
is available on Redox OS too.
Simulate OOM for the `try_oom_error` test
We can create the expected error manually, rather than trying to produce
a real one, so the error conversion test can run on all targets. Before,
it was only running on 64-bit and not miri.
In Fedora, we also found that s390x was not getting the expected error,
"successfully" allocating the huge size because it was optimizing the
real `malloc` call away. It's possible to counter that by looking at the
pointer in any way, like a debug print, but it's more robust to just
deal with errors directly, since this test is only about conversion.
Related: #133806
Implement `read_buf` and vectored read/write for SGX stdio
Implement `read_buf`, `read_vectored`, and `write_vectored` for the SGX stdio types.
Additionally, extend `User<T>::copy_to_enclave` to work for copying to uninitialized values and fix unsoundness in `UserRef<[T]>::copy_to_enclave_vec`.
cc ``@jethrogb``
Tracked in https://github.com/rust-lang/rust/issues/136756
uefi: fs: Implement FileType, FilePermissions and FileAttr
- In UEFI, both FileType and FilePermissions are represented by the attr bitfield.
- Using simple bools here since both are represented by a single bit.
- Add `FILE_PERMISSION` mask for constructing attribute while change permissions.
cc ````@nicholasbishop````
