This adds both a test specific to #108453 as well as an exhaustive test
that goes through all possible combinations of head index, length and target capacity
for a deque with capacity 16.
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
Optimize break patterns
Use `wyrand` instead of calling `XORSHIFT` 2 times in break patterns for the 64-bit platform. The new PRNG is 2x faster than the previous one.
Bench result(via https://gist.github.com/zhangyunhao116/11ef41a150f5c23bb47d86255fbeba89):
```
old time: [1.3258 ns 1.3262 ns 1.3266 ns]
change: [+0.5901% +0.6731% +0.7791%] (p = 0.00 < 0.05)
Change within noise threshold.
Found 13 outliers among 100 measurements (13.00%)
7 (7.00%) high mild
6 (6.00%) high severe
new time: [657.65 ps 657.89 ps 658.18 ps]
change: [-1.6910% -1.6110% -1.5256%] (p = 0.00 < 0.05)
Performance has improved.
Found 6 outliers among 100 measurements (6.00%)
2 (2.00%) high mild
4 (4.00%) high severe
```
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".
implement const iterator using `rustc_do_not_const_check`
Previous experiment: #102225.
Explanation: rather than making all default methods work under `const` all at once, this uses `rustc_do_not_const_check` as a workaround to "trick" the compiler to not run any checks on those other default methods. Any const implementations are only required to implement the `next` method. Any actual calls to the trait methods other than `next` will either error in compile time (at CTFE runs), or run the methods correctly if they do not have any non-const operations. This is extremely easy to maintain, remove, or improve.
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.
This changes the documentation of `std::panic::set_hook` and `take_hook` to better 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.
Document that CStr::as_ptr returns a type alias
Rustdoc resolves type aliases too eagerly #15823 which makes the [std re-export](https://doc.rust-lang.org/stable/std/ffi/struct.CStr.html#method.as_ptr) of `CStr::as_ptr` show `i8` instead of `c_char`. To work around this I've added info about `c_char` in the method's description.
BTW, I've also added a comment to what-not-to-do example in case someone copypasted it without reading the surrounding text.
Implement more methods for `vec_deque::IntoIter`
This implements a couple `Iterator` methods on `vec_deque::IntoIter` (`(try_)fold`, `(try_)rfold` `advance_(back_)by`, `next_chunk`, `count` and `last`) to allow these to be more efficient than their default implementations, also allowing many other `Iterator` methods that use these under the hood to take advantage of these manual implementations. `vec::IntoIter` has similar implementations for many of these methods. This PR does not yet implement `TrustedRandomAccess` and friends, as I'm not very familiar with the required safety guarantees.
r? `@the8472` (since you also took over my last PR)
Optimize `LazyLock` size
The initialization function was unnecessarily stored separately from the data to be initialized. Since both cannot exist at the same time, a `union` can be used, with the `Once` acting as discriminant. This unfortunately requires some extra methods on `Once` so that `Drop` can be implemented correctly and efficiently.
`@rustbot` label +T-libs +A-atomic
Demonstrate I/O in File examples
I've noticed that some Rust novices unnecessarily reinvent `std::fs::{read,write}`, presumably because they search for equivalents of `fopen` + `fwrite`. I've added links to `std::fs::{read,write}` in the docs.
The `File` examples were only showing how to open a file, but not how to use the opened handle, unnecessarily leaving out the next step. I've added a variety of different uses of file handles to their examples in docs.
