Improve documentation on process::Child.std* fields
As a relative beginner, it took a while for me to figure out I could just steal the references to avoid partially moving the child and thus retain ability to call functions on it (and store it in structs etc).
As a relative beginner, it took a while for me to figure out I could just steal the references to avoid partially moving the child and thus retain ability to call functions on it (and store it in structs etc).
Expand function pointer docs
Be more explicit in the ABI section, and add a section on how to obtain a function pointer, which can be somewhat confusing.
Cc https://github.com/rust-lang/rust/issues/75239
Move to intra doc links whenever possible within std/src/lib.rs
Helps with #75080.
@rustbot modify labels: T-doc, A-intra-doc-links, T-rustdoc
There are some things like
```rust
`//! [`Option<T>`]: option::Option`
```
that will either be fixed in the future or have open issues about them.
Fix minor things in the `f32` primitive docs
All of these were review comments in #74621 that I first fixed in that PR, but later accidentally overwrote by a force push.
Thanks @the8472 for noticing.
r? @KodrAus
Fix wasi::fs::OpenOptions to imply write when append is on
This PR fixes a bug in `OpenOptions` of `wasi` platform that it currently doesn't imply write mode when only `append` is enabled.
As explained in the [doc of OpenOptions#append](https://doc.rust-lang.org/std/fs/struct.OpenOptions.html#method.append), calling `.append(true)` should imply `.write(true)` as well.
## Reproduce
Given below simple Rust program:
```rust
use std::fs::OpenOptions;
use std::io::Write;
fn main() {
let mut file = OpenOptions::new()
.write(true)
.create(true)
.open("foo.txt")
.unwrap();
writeln!(file, "abc").unwrap();
}
```
it can successfully compiled into wasm and execute by `wasmtime` runtime:
```sh
$ rustc --target wasm32-wasi write.rs
$ ~/wasmtime/target/debug/wasmtime run --dir=. write.wasm
$ cat foo.txt
abc
```
However when I change `.write(true)` to `.append(true)`, it fails to execute by the error "Capabilities insufficient":
```sh
$ ~/wasmtime/target/debug/wasmtime run --dir=. append.wasm
thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 76, kind: Other, message: "Capabilities insufficient" }', append.rs:10:5
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Error: failed to run main module `append.wasm`
...
```
This is because of lacking "rights" on the opened file:
```sh
$ RUST_LOG=trace ~/wasmtime/target/debug/wasmtime run --dir=. append.wasm 2>&1 | grep validate_rights
TRACE wasi_common::entry > | validate_rights failed: required rights = HandleRights { base: fd_write (0x40), inheriting: empty (0x0) }; actual rights = HandleRights { base: fd_seek|fd_fdstat_set_flags|fd_sync|fd_tell|fd_advise|fd_filestat_set_times|poll_fd_readwrite (0x88000bc), inheriting: empty (0x0) }
```
Add Ipv6Addr::to_ipv4_mapped
* add Ipv6Addr::to_ipv4_mapped
* ~~deprecate Ipv4Addr::to_ipv6_compatible & Ipv6Addr::to_ipv4~~ reference: #75150
According to [IETF RFC 4291](https://tools.ietf.org/html/rfc4291#page-10), the "IPv4-Compatible IPv6 address" is deprecated.
> 2.5.5.1. IPv4-Compatible IPv6 Address
>
> The "IPv4-Compatible IPv6 address" was defined to assist in the IPv6
> transition. The format of the "IPv4-Compatible IPv6 address" is as
> follows:
>
> | 80 bits | 16 | 32 bits |
> +--------------------------------------+--------------------------+
> |0000..............................0000|0000| IPv4 address |
> +--------------------------------------+----+---------------------+
>
> Note: The IPv4 address used in the "IPv4-Compatible IPv6 address"
> must be a globally-unique IPv4 unicast address.
>
> The "IPv4-Compatible IPv6 address" is now deprecated because the
> current IPv6 transition mechanisms no longer use these addresses.
> New or updated implementations are not required to support this
> address type.
And the current implementation of `Ipv4Addr::to_ipv6_compatible`is incorrect: it does not check whether the IPv4 address is a globally-unique IPv4 unicast address.
Please let me know if there are any issues with this pull request.
Improve `f32` and `f64` primitive documentation
I noticed that the docs for the primitive floats were fairly short. I first only wanted to add the IEEE specification information (compare [the reference](https://doc.rust-lang.org/reference/types/numeric.html)), but then also added some more beginner-friendly docs. Let me know what you think!
Random doc team assign:
r? @rylev
Std panicking unsafe block in unsafe fn
Partial fix of #73904.
This encloses `unsafe` operations in `unsafe fn` in `libstd/ffi/panicking.rs`.
I also made a two lines change to `libstd/thread/local.rs` to add the necessary `unsafe` block without breaking everything else.
@rustbot modify labels: F-unsafe-block-in-unsafe-fn
Unfortunately, sanitizers do not support versioned symbols[1],
so they break filesystem access via the legacy, pre-ino64 ABI.
To use sanitizers on FreeBSD >= 12, we need to build the libc
crate with LIBC_CI=1 to use the new ABI -- including the libc
used for std. But that removes the st_lspare field std was
expecting for the deprecated metadata extension.
Add a way to skip that field to allow the build to work.
[1]: https://github.com/google/sanitizers/issues/628
Move to intra-doc links in library/std/src/path.rs
Helps with #75080.
@rustbot modify labels: T-doc, A-intra-doc-links, T-rustdoc
Known issue: The following links are broken (they are inside trait impls, undocumented in this file, inheriting from the original doc):
- [`Hasher`]
- [`Self`] (referencing `../primitive.slice.html`)
- [`Ordering`]
remove_dir will error if the path doesn't exist or isn't a directory.
It's useful to clarify that this is "remove dir or fail" not "remove dir
if it exists".
I don't think this belongs in the title. "Removes an existing, empty
directory" is strangely worded-- there's no such thing as a non-existing
directory. Better to just say explicitly it will return an error.
Implement `into_keys` and `into_values` for associative maps
This PR implements `into_keys` and `into_values` for HashMap and BTreeMap types. They are implemented as unstable, under `map_into_keys_values` feature.
Fixes#55214.
r? @dtolnay
All #[cfg(unix)] platforms follow the POSIX standard and define _SC_IOV_MAX so
that we rely purely on POSIX semantics to determine the limits on I/O vector
count.
Keep the I/O vector count limit in a `SyncOnceCell` to avoid the overhead of
repeatedly calling `sysconf` as these limits are guaranteed to not change during
the lifetime of a process by POSIX.
Both Linux and MacOS enforce limits on the vector count when performing vectored
I/O via the readv and writev system calls and return EINVAL when these limits
are exceeded. This changes the standard library to handle those limits as short
reads and writes to avoid forcing its users to query these limits using
platform specific mechanisms.
Co-authored-by: Weiyi Wang <wwylele@gmail.com>
Co-authored-by: Adam Reichold <adam.reichold@t-online.de>
Co-authored-by: Josh Stone <cuviper@gmail.com>
Co-authored-by: Scott McMurray <scottmcm@users.noreply.github.com>
Co-authored-by: tmiasko <tomasz.miasko@gmail.com>
Previously `std::fs::File::metadata` on wasm32-wasi would call `fd_filestat_get`
to get metadata associated with fd, but that fd is opened without
RIGHTS_FD_FILESTAT_GET right, so it will failed on correctly implemented WASI
environment.
This change instead to add the missing rights when opening an fd.
Remove links to rejected errata 4406 for RFC 4291
Fixes#74198.
For now I simply removed the links, the docs seems clear enough to me but I'm no expert in the domain so don't hesitate to correct me if more is needed.
cc @ghanan94.
@rustbot modify labels: T-doc, T-libs
