The interaction between the environment variable methods can be confusing. Specifically `env_clear` and `remove_env` have a side effects not mentioned: they disable inheriting environment variables from the parent process. I wanted to fully document this behavior as well as explain relevant edge cases in each of the `Command` env methods.
This is further confused by the return of `get_envs` which will return key/None if `remove_env` has been used, but an empty iterator if `env_clear` has been called. Or a non-empty iterator if `env_clear` was called and later explicit mappings are added. Currently there is no way (that I'm able to find) of observing whether or not the internal `env_clear=true` been toggled on the `Command` struct via its public API.
Ultimately environment variable mappings can be in one of several states:
- Explicitly set value (via `envs` / `env`) will take precedence over parent mapping
- Not explicitly set, will inherit mapping from parent
- Explicitly removed via `remove_env`, this single mapping will not inherit from parent
- Implicitly removed via `env_clear`, no mappings will inherit from parent
I tried to represent this in the relevant sections of the docs.
This is my second ever doc PR (whoop!). I'm happy to take specific or general doc feedback. Also happy to explain the logic behind any changes or additions I made.
use `as_ptr` to determine the address of atomics
The PR #107736 renamed atomic `as_mut_ptr` to `as_ptr`. Consequently, the futex implementation of the tier-3 platform `RutyHermit` has to use this new interface. In addition, this PR removes also an unused import.
Stabilize `atomic_as_ptr`
Fixes#66893
This stabilizes the `as_ptr` methods for atomics. The stabilization feature gate used here is `atomic_as_ptr` which supersedes `atomic_mut_ptr` to match the change in https://github.com/rust-lang/rust/pull/107736.
This needs FCP.
New stable API:
```rust
impl AtomicBool {
pub const fn as_ptr(&self) -> *mut bool;
}
impl AtomicI32 {
pub const fn as_ptr(&self) -> *mut i32;
}
// Includes all other atomic types
impl<T> AtomicPtr<T> {
pub const fn as_ptr(&self) -> *mut *mut T;
}
```
r? libs-api
``@rustbot`` label +needs-fcp
Move __thread_local_inner to sys
Move `__thread_local_inner` macro in `crate:🧵:local` to `crate::sys`. Initially, I was thinking about removing this macro completely, but I could not find a way to create the generic statics without macros, so in the end, I just moved to code around.
This probably will need a rebase once https://github.com/rust-lang/rust/pull/108917 is merged
r? ``@workingjubilee``
This allows removing all the platform-dependent code from `library/std/src/thread/local.rs` and `library/std/src/thread/mod.rs`
Signed-off-by: Ayush Singh <ayushsingh1325@gmail.com>
Split the __thread_local_inner macro to make it more readable. Also move
everything to crate::sys::common::thread_local.
Signed-off-by: Ayush Singh <ayushsingh1325@gmail.com>
Move __thread_local_inner macro in crate:🧵:local to crate::sys.
Currently, the tidy check does not fail for `library/std/src/thread/local.rs` even though it contains platform specific code. This is beacause target_family did not exist at the time the tidy checks were written [1].
[1]: https://github.com/rust-lang/rust/pull/105861#discussion_r1125841678
Signed-off-by: Ayush Singh <ayushsingh1325@gmail.com>
Add `round_ties_even` to `f32` and `f64`
Tracking issue: #96710
Redux of #82273. See also #55107
Adds a new method, `round_ties_even`, to `f32` and `f64`, that rounds the float to the nearest integer , rounding halfway cases to the number with an even least significant bit. Uses the `roundeven` LLVM intrinsic to do this.
Of the five IEEE 754 rounding modes, this is the only one that doesn't already have a round-to-integer function exposed by Rust (others are `round`, `floor`, `ceil`, and `trunc`). Ties-to-even is also the rounding mode used for int-to-float and float-to-float `as` casts, as well as float arithmentic operations. So not having an explicit rounding method for it seems like an oversight.
Bikeshed: this PR currently uses `round_ties_even` for the name of the method. But maybe `round_ties_to_even` is better, or `round_even`, or `round_to_even`?
Add vectored positioned I/O on Unix
Add methods for vectored I/O with an offset on `File` for `unix` under `#![feature(unix_file_vectored_at)]`.
The new methods are wrappers around `preadv` and `pwritev`.
Tracking issue: #89517
Add support for QNX Neutrino to standard library
This change:
- adds standard library support for QNX Neutrino (7.1).
- upgrades `libc` to version `0.2.139` which supports QNX Neutrino
`@gh-tr`
⚠️ Backtraces on QNX require https://github.com/rust-lang/backtrace-rs/pull/507 which is not yet merged! (But everything else works without these changes) ⚠️
Tested mainly with a x86_64 virtual machine (see qnx-nto.md) and partially with an aarch64 hardware (some tests fail due to constrained resources).
[stdio][windows] Use MBTWC and WCTMB
`MultiByteToWideChar` and `WideCharToMultiByte` are extremely well optimized, and therefore should probably be used when we know we can (specifically in the Windows stdio stuff).
Fixes#107092
add support of RustyHermit's BSD socket layer
RustyHermit is a tier 3 platform and publishes a new kernel interface. The new version supports a common BSD socket layer. By supporting this interface, the implementation of `std` can be harmonized to other operating systems. In `sys_common/mod.rs` we remove only a special case for RustyHermit. All changes are done in the RustyHermit specific directories.
To realize this socket layer, the handling of file descriptors is also harmonized to other operating systems.
Move some std tests from `tests/ui-fulldeps` into `library/std`
This allows them to be tested normally along with other `./x test std` tests. Moving `rename_directory` is simple enough but `create_dir_all_bare` needed to be an std integration test.
Additionally, some tests that I couldn't move atm have instead been placed in an `std` subdirectory. These tests include ones that do fun things with processes or that intentionally abort the test process.
r? libs
RustHermit publishs a new kernel interface and supports
a common BSD socket layer. By supporting this interface,
the implementation can be harmonized to other operating systems.
To realize this socket layer, the handling of file descriptors
is also harmonized to other operating systems.
Fix `is_terminal`'s handling of long paths on Windows.
As reported in sunfishcode/is-terminal#18, there are situations where `GetFileInformationByHandleEx` can write a file name length that is longer than the provided buffer. To avoid deferencing memory past the end of the buffer, use a bounds-checked function to form a slice to the buffer and handle the out-of-bounds case.
This ports the fix from sunfishcode/is-terminal#19 to std's `is_terminal` implementation.
std: time: Avoid to use "was created" in elapsed() description
".. since this instant was created" is inaccurate and misleading, consider the following case:
```rust
let i1 = Instant::now(); // i1 is created at T1
let i2 = i1 + Duration::from_nanos(0); // i2 is "created" at T2
i2.elapsed(); // at T3
```
Per the current description, `elapsed()` at T3 should return T3 - T2?
To avoid the inaccuracy, removes the "was created" in the description of {Instant,SystemTime}::elapsed().
And since these types represent times, it's OK to use prepostions with them, e.g. "since this instant".
As reported in sunfishcode/is-terminal#18, there are situations where
`GetFileInformationByHandleEx` can write a file name length that is
longer than the provided buffer. To avoid deferencing memory past the
end of the buffer, use a bounds-checked function to form a slice to
the buffer and handle the out-of-bounds case.
This ports the fix from sunfishcode/is-terminal#19 to std's `is_terminal`
implementation.
Windows: Quote more batch file arguments
Make sure to always quote batch file arguments that contain command prompt special characters.
Additionally add `/d` command line parameter to disable any autorun scripts that may change the way variable expansion works. This makes it more consistent across systems and may help avoid surprises.
## Background Info
[`CreateProcess`](https://learn.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-createprocessw) with the `lpApplicationName` set can only be used to run `.exe` files and not script files such as `.bat`. However, for historical reasons, we do have special handling so that `.bat` files will be correctly run with `cmd.exe` as the application.
In Windows, command line arguments are passed as a single string (not an array). Applications can parse this string however they like but most follow the standard MSVC C/C++ convention. But `cmd.exe` uses different argument parsing rules to other Windows programs (because it emulates old DOS). This PR aims to help smooth over some of the differences.
r? libs
".. since this instant was created" is inaccurate and misleading,
consider the following case:
let i1 = Instant::now(); // i1 is created at T1
let i2 = i1 + Duration::from_nanos(0); // i2 is "created" at T2
i2.elapsed(); // at T3
Per the current description, `elapsed()` at T3 should return T3 - T2?
Therefore removes the "was created" in the description of
{Instant,SystemTime}::elapsed(). And since these types represent times,
it's OK to use prepostions with them, e.g. "since this instant".
Rename atomic 'as_mut_ptr' to 'as_ptr' to match Cell (ref #66893)
Originally discussed in https://github.com/rust-lang/rust/issues/66893#issuecomment-1419198623
~~This uses #107706 as a base to avoid a merge conflict once that gets rolled up (so disregard const changes in the diff until it does)~~ all merged & rebased
`@rustbot` label +T-libs-api
r? m-ou-se
Make sure to quote batch file arguments that contain command prompt special characters.
Additionally add `/d` command line parameter to disable any commands that may change the way variable expansion works.
Moving `create_dir_all` out of `ui-fulldeps` is complicated by the fact it sets the current directory. This means it can't be a unit test. Instead, move it to its own integration test.
docs: wrong naming convention in struct keyword doc
Noticed that the naming convention mentioned is not the right one.
As far as I know, PacalCase is the naming convention used for structs names. PacalCase is not the same as camelCase
Explain the default panic hook better
This changes the documentation of `std::panic::set_hook` and `take_hook` to explain how the default panic hook works. In particular the fact that `take_hook` registers the default hook, rather than no hook at all, was missing from the docs.
I also reworded a few things for clarity.
