[fuchsia] Propagate the userspace UTC clock
On Fuchsia, spawning a subprocess does not automatically
clone all of the parent process' capabilities. UTC time on
Fuchsia is managed by a top-level userspace clock capability
that is cloned and passed to subprocesses.
This change ensures that any Rust subprocess gets access to the
UTC clock, if the parent had access to it. This is critical for
tests, which on Fuchsia, use panic=abort and spawn subprocesses
per test.
Consolidate some duplicate code in the sys modules.
This consolidates some modules which were duplicated throughout the sys module. The intent is to make it easier to update and maintain this code. This mainly affects the wasi, sgx, and "unsupported" targets.
I explicitly skipped hermit, cloudabi, and vxworks. These tier-3 targets have copied large sections of the sys tree. I don't think they should have, but I don't want to put effort into changing them. It also doesn't help that there aren't any scripts or instructions for building them.
There are still sections of duplicate code here and there, but this PR covers the easy parts where entire modules are the same.
On Fuchsia, spawning a subprocess does not automatically
clone all of the parent process' capabilities. UTC time on
Fuchsia is managed by a top-level userspace clock capability
that is cloned and passed to subprocesses.
This change ensures that any Rust subprocess gets access to the
UTC clock, if the parent had access to it. This is critical for
tests, which on Fuchsia, use panic=abort and spawn subprocesses
per test.
Implementation of peer credentials for Unix sockets
The code in `ucred.rs` is based on the work done in [PR 13](https://github.com/tokio-rs/tokio-uds/pull/13) in the tokio-uds repository on GitHub.
This commit is effectively a port to the stdlib, so credit to Martin Habovštiak (`@Kixunil)` and contributors for the meat of this work. 🥇
Happy to make changes as needed. 🙂
The code in `ucred.rs` is based on the work done in PR 13 in the
tokio-uds repository on GitHub. Link below for reference:
https://github.com/tokio-rs/tokio-uds/pull/13
Credit to Martin Habovštiak (GitHub username Kixunil) and contributors
for this work!
Use IOV_MAX and UIO_MAXIOV constants in limit vectored I/O
Also updates the libc dependency to 0.2.77 (from 0.2.74) as the
constants were only recently added.
Related #68042, #75005
r? `@Amanieu` (also reviewed #75005)
Update `std::os` module documentation.
Adds missing descriptions for the modules `std::os::linux::fs` and `std::os::windows::io`.
Also adds punctuation for consistency with other descriptions.
The calling convention of pthread_getattr_np() is to initialize the
pthread_attr_t, so _destroy() is only necessary on success (and _init()
isn't necessary beforehand). On the other hand, FreeBSD wants the
attr_t to be initialized before pthread_attr_get_np(), and therefore it
should always be destroyed afterwards.
- Use intra-doc links for `std::io` in `std::fs`
- Use intra-doc links for File::read in unix/ext/fs.rs
- Remove explicit intra-doc links for `true` in `net/addr.rs`
- Use intra-doc links in alloc/src/sync.rs
- Use intra-doc links in src/ascii.rs
- Switch to intra-doc links in alloc/rc.rs
- Use intra-doc links in core/pin.rs
- Use intra-doc links in std/prelude
- Use shorter links in `std/fs.rs`
`io` is already in scope.
This solves several problems
- race conditions where a file is truncated while copying from it. if we blindly trusted
the file size this would lead to an infinite loop
- proc files appearing empty to copy_file_range but not to read/write
https://github.com/coreutils/coreutils/commit/4b04a0c
- copy_file_range returning 0 for some filesystems (overlay? bind mounts?)
inside docker, again leading to an infinite loop
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.
