Add the following trait impls:
- `impl Extend<OsString> for OsString`
- `impl<'a> Extend<&'a OsStr> for OsString`
- `impl FromIterator<OsString> for OsString`
- `impl<'a> FromIterator<&'a OsStr> for OsString`
Because `OsString` is a platform string with no particular semantics,
concatenating them together seems acceptable.
use RWlock when accessing os::env
Multiple threads modifying the current process environment is fairly uncommon. Optimize for the more common read case.
r? ````@m-ou-se````
Upgrade wasm32 image to Ubuntu 20.04
This switches the wasm32 image, which is used to test
wasm32-unknown-emscripten, to Ubuntu 20.04. While at it, enable
most of the excluded tests, as they seem to work fine with some
minor fixes.
This switches the wasm32 image, which is used to test
wasm32-unknown-emscripten to Ubuntu 20.04. While at it, enable
most of the excluded tests, as they seem to work fine with some
minor fixes.
Expose correct symlink API on WASI
As described in https://github.com/rust-lang/rust/issues/68574, the currently exposed API for symlinks is, in fact, a thin wrapper around the corresponding syscall, and not suitable for public usage.
The reason is that the 2nd param in the call is expected to be a handle of a "preopened directory" (a WASI concept for exposing dirs), and the only way to retrieve such handle right now is by tinkering with a private `__wasilibc_find_relpath` API, which is an implementation detail and definitely not something we want users to call directly.
Making matters worse, the semantics of this param aren't obvious from its name (`fd`), and easy to misinterpret, resulting in people trying to pass a handle of the target file itself (as in https://github.com/vitiral/path_abs/pull/50), which doesn't work as expected.
I did a [codesearch among open-source repos](https://sourcegraph.com/search?q=std%3A%3Aos%3A%3Awasi%3A%3Afs%3A%3Asymlink&patternType=literal), and the usage above is so far the only usage of this API at all, but we should fix it before more people start using it incorrectly.
While this is technically a breaking API change, I believe it's a justified one, as 1) it's OS-specific and 2) there was strictly no way to correctly use the previous form of the API, and if someone does use it, they're likely doing it wrong like in the example above.
The new API does not lead to the same confusion, as it mirrors `std::os::unix::fs::symlink` and `std::os::windows::fs::symlink_{file,dir}` variants by accepting source/target paths.
Fixes#68574.
r? ``@alexcrichton``
Stabilize poison API of Once, rename poisoned()
This stabilizes:
* `OnceState`
* `OnceState::is_poisoned()` (previously named `poisoned()`)
* `Once::call_once_force()`
`poisoned()` was renamed because the new name is more clear as a few
people agreed and nobody objected.
Closes#33577
Notes:
* I'm not entirely sure it's supposed to be 1.51, LMK if I did it wrong
* I failed to run tests locally, so we will have to leave it to bors or someone else can try
OsStr eq_ignore_ascii_case takes arg by value
Per a comment on #70516 this changes `eq_ignore_ascii_case` to take the generic parameter `S: AsRef<OsStr>` by value instead of by reference.
This is technically a breaking change to an unstable method. I think the only way it would break is if you called this method with an explicit type parameter, ie `my_os_str.eq_ignore_ascii_case::<str>("foo")` becomes `my_os_str.eq_ignore_ascii_case::<&str>("foo")`.
Besides that, I believe it is overall more flexible since it can now take an owned `OsString` for example.
If this change should be made in some other PR (like #80193) then please just close this.
This stabilizes:
* `OnceState`
* `OnceState::is_poisoned()` (previously named `poisoned()`)
* `Once::call_once_force()`
`poisoned()` was renamed because the new name is more clear as a few
people agreed and nobody objected.
Closes#33577
Per a comment on #70516 this changes `eq_ignore_ascii_case` to take the generic parameter `S: AsRef<OsStr>` by value instead of by reference.
This is technically a breaking change to an unstable method. I think the only way it would break is if you called this method with an explicit type parameter, ie `my_os_str.eq_ignore_ascii_case::<str>("foo")` becomes `my_os_str.eq_ignore_ascii_case::<&str>("foo")`.
Besides that, I believe it is overall more flexible since it can now take an owned `OsString` for example.
If this change should be made in some other PR (like #80193) then please just close this.
Add doc aliases for "delete"
This patch adds doc aliases for "delete". The added aliases are supposed to reference usages `delete` in other programming languages.
- `HashMap::remove`, `BTreeMap::remove` -> `Map#delete` and `delete` keyword in JavaScript.
- `HashSet::remove`, `BTreeSet::remove` -> `Set#delete` in JavaScript.
- `mem::drop` -> `delete` keyword in C++.
- `fs::remove_file`, `fs::remove_dir`, `fs::remove_dir_all`-> `File#delete` in Java, `File#delete` and `Dir#delete` in Ruby.
Before this change, searching for "delete" in documentation returned no results.
sys: use `process::abort()` instead of `arch::wasm32::unreachable()`
Rationale:
- `abort()` lowers to `wasm32::unreachable()` anyway.
- `abort()` isn't `unsafe`.
- `abort()` matches the comment better.
- `abort()` avoids confusion by future readers (e.g. https://github.com/rust-lang/rust/pull/81527): the naming of wasm's `unreachable` instruction is a bit unfortunate because it is not related to the `unreachable()` intrinsic (intended to trigger UB).
Codegen is likely to be different since `unreachable()` is `inline` while `abort()` is `cold`. Since it doesn't look like we are expecting here to trigger this case, the latter seems better anyway.
Add AArch64 big-endian and ILP32 targets
This PR adds 3 new AArch64 targets:
- `aarch64_be-unknown-linux-gnu`
- `aarch64-unknown-linux-gnu_ilp32`
- `aarch64_be-unknown-linux-gnu_ilp32`
It also fixes some ABI issues on big-endian ARM and AArch64.
Fix calling convention for CRT startup
My PR #81478 used the wrong calling convention for a set of
functions that are called by the CRT. These functions need to use
`extern "C"`.
This would only affect x86, which is the only target (that I know of)
that has multiple calling conventions.
```@bors``` r? ```@m-ou-se```
Let io::copy reuse BufWriter buffers
This optimization will allow users to implicitly set the buffer size for io::copy by wrapping the writer into a `BufWriter` if the default block size is insufficient, which should fix#49921
Due to min_specialization limitations this approach only works with `BufWriter` but not for `BufReader<R>` since `R` is unconstrained and thus the necessary specialization on `R: Read` is not always applicable. Once specialization becomes more powerful this optimization could be extended to look at the reader and writer side and use whichever buffer is larger.
Implement Rust 2021 panic
This implements the Rust 2021 versions of `panic!()`. See https://github.com/rust-lang/rust/issues/80162 and https://github.com/rust-lang/rfcs/pull/3007.
It does so by replacing `{std, core}::panic!()` by a bulitin macro that expands to either `$crate::panic::panic_2015!(..)` or `$crate::panic::panic_2021!(..)` depending on the edition of the caller.
This does not yet make std's panic an alias for core's panic on Rust 2021 as the RFC proposes. That will be a separate change: c5273bdfb2 That change is blocked on figuring out what to do with https://github.com/rust-lang/rust/issues/80846 first.
My PR #81478 used the wrong calling convention for a set of
functions that are called by the CRT. These functions need to use
`extern "C"`.
This would only affect x86, which is the only target (that I know of)
that has multiple calling conventions.
This patch adds doc aliases for "delete". The added aliases are
supposed to reference usages `delete` in other programming
languages.
- `HashMap::remove`, `BTreeMap::remove` -> `Map#delete` and `delete`
keyword in JavaScript.
- `HashSet::remove`, `BTreeSet::remove` -> `Set#delete` in JavaScript.
- `mem::drop` -> `delete` keyword in C++.
- `fs::remove_file`, `fs::remove_dir`, `fs::remove_dir_all`
-> `File#delete` in Java, `File#delete` and `Dir#delete` in Ruby.
Before this change, searching for "delete" in documentation
returned no results.
Resolve DLL imports at CRT startup, not on demand
On Windows, libstd uses GetProcAddress to locate some DLL imports, so
that libstd can run on older versions of Windows. If a given DLL import
is not present, then libstd uses other behavior (such as fallback
implementations).
This commit uses a feature of the Windows CRT to do these DLL imports
during module initialization, before main() (or DllMain()) is called.
This is the ideal time to resolve imports, because the module is
effectively single-threaded at that point; no other threads can
touch the data or code of the module that is being initialized.
This avoids several problems. First, it makes the cost of performing
the DLL import lookups deterministic. Right now, the DLL imports are
done on demand, which means that application threads _might_ have to
do the DLL import during some time-sensitive operation. This is a
small source of unpredictability. Since threads can race, it's even
possible to have more than one thread running the same redundant
DLL lookup.
This commit also removes using the heap to allocate strings, during
the DLL lookups.
Stabilize raw ref macros
This stabilizes `raw_ref_macros` (https://github.com/rust-lang/rust/issues/73394), which is possible now that https://github.com/rust-lang/rust/issues/74355 is fixed.
However, as I already said in https://github.com/rust-lang/rust/issues/73394#issuecomment-751342185, I am not particularly happy with the current names of the macros. So I propose we also change them, which means I am proposing to stabilize the following in `core::ptr`:
```rust
pub macro const_addr_of($e:expr) {
&raw const $e
}
pub macro mut_addr_of($e:expr) {
&raw mut $e
}
```
The macro name change means we need another round of FCP. Cc `````@rust-lang/libs`````
Fixes#73394
Add `core::stream::Stream`
[[Tracking issue: #79024](https://github.com/rust-lang/rust/issues/79024)]
This patch adds the `core::stream` submodule and implements `core::stream::Stream` in accordance with [RFC2996](https://github.com/rust-lang/rfcs/pull/2996). The RFC hasn't been merged yet, but as requested by the libs team in https://github.com/rust-lang/rfcs/pull/2996#issuecomment-725696389 I'm filing this PR to get the ball rolling.
## Documentatation
The docs in this PR have been adapted from [`std::iter`](https://doc.rust-lang.org/std/iter/index.html), [`async_std::stream`](https://docs.rs/async-std/1.7.0/async_std/stream/index.html), and [`futures::stream::Stream`](https://docs.rs/futures/0.3.8/futures/stream/trait.Stream.html). Once this PR lands my plan is to follow this up with PRs to add helper methods such as `stream::repeat` which can be used to document more of the concepts that are currently missing. That will allow us to cover concepts such as "infinite streams" and "laziness" in more depth.
## Feature gate
The feature gate for `Stream` is `stream_trait`. This matches the `#[lang = "future_trait"]` attribute name. The intention is that only the APIs defined in RFC2996 will use this feature gate, with future additions such as `stream::repeat` using their own feature gates. This is so we can ensure a smooth path towards stabilizing the `Stream` trait without needing to stabilize all the APIs in `core::stream` at once. But also don't start expanding the API until _after_ stabilization, as was the case with `std::future`.
__edit:__ the feature gate has been changed to `async_stream` to match the feature gate proposed in the RFC.
## Conclusion
This PR introduces `core::stream::{Stream, Next}` and re-exports it from `std` as `std::stream::{Stream, Next}`. Landing `Stream` in the stdlib has been a mult-year process; and it's incredibly exciting for this to finally happen!
---
r? `````@KodrAus`````
cc/ `````@rust-lang/wg-async-foundations````` `````@rust-lang/libs`````
As described in https://github.com/rust-lang/rust/issues/68574, the currently exposed API for symlinks is, in fact, a thin wrapper around the corresponding syscall, and not suitable for public usage.
The reason is that the 2nd param in the call is expected to be a handle of a "preopened directory" (a WASI concept for exposing dirs), and the only way to retrieve such handle right now is by tinkering with a private `__wasilibc_find_relpath` API, which is an implementation detail and definitely not something we want users to call directly.
Making matters worse, the semantics of this param aren't obvious from its name (`fd`), and easy to misinterpret, resulting in people trying to pass a handle of the target file itself (as in https://github.com/vitiral/path_abs/pull/50), which doesn't work as expected.
I did a codesearch among open-source repos, and the usage above is so far the only usage of this API at all, but we should fix it before more people start using it incorrectly.
While this is technically a breaking API change, I believe it's a justified one, as 1) it's OS-specific and 2) there was strictly no way to correctly use the previous form of the API, and if someone does use it, they're likely doing it wrong like in the example above.
The new API does not lead to the same confusion, as it mirrors `std::os::unix::fs::symlink` and `std::os::windows::fs::symlink_{file,dir}` variants by accepting source/target paths.
Fixes#68574.
Rationale:
- `abort()` lowers to `wasm32::unreachable()` anyway.
- `abort()` isn't `unsafe`.
- `abort()` matches the comment better.
- `abort()` avoids confusion by future readers (e.g.
https://github.com/rust-lang/rust/pull/81527): the naming of wasm's
`unreachable' instruction is a bit unfortunate because it is not
related to the `unreachable()` intrinsic (intended to trigger UB).
Codegen is likely to be different since `unreachable()` is `inline`
while `abort()` is `cold`. Since it doesn't look like we are expecting
here to trigger this case, the latter seems better anyway.
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
On Windows, libstd uses GetProcAddress to locate some DLL imports, so
that libstd can run on older versions of Windows. If a given DLL import
is not present, then libstd uses other behavior (such as fallback
implementations).
This commit uses a feature of the Windows CRT to do these DLL imports
during module initialization, before main() (or DllMain()) is called.
This is the ideal time to resolve imports, because the module is
effectively single-threaded at that point; no other threads can
touch the data or code of the module that is being initialized.
This avoids several problems. First, it makes the cost of performing
the DLL import lookups deterministic. Right now, the DLL imports are
done on demand, which means that application threads _might_ have to
do the DLL import during some time-sensitive operation. This is a
small source of unpredictability. Since threads can race, it's even
possible to have more than one thread running the same redundant
DLL lookup.
This commit also removes using the heap to allocate strings, during
the DLL lookups.
Stabilize `Seek::stream_position` (feature `seek_convenience`)
Tracking issue: #59359
Unresolved questions from tracking issue:
- "Override `stream_len` for `File`?" → we can do that in the future, this does not block stabilization.
- "Rename to `len` and `position`?" → as noted in the tracking issue, both of these shorter names have problems (`len` is usually a cheap getter, `position` clashes with `Cursor`). I do think the current names are perfectly fine.
- "Rename `stream_position` to `tell`?" → as mentioned in [the comment bringing this up](https://github.com/rust-lang/rust/issues/59359#issuecomment-559541545), `stream_position` is more descriptive. I don't think `tell` would be a good name.
What remains to decide, is whether or not adding these methods is worth it.
Trying to shrink_to greater than capacity should be no-op
Per the discussion in https://github.com/rust-lang/rust/issues/56431, `shrink_to` shouldn't panic if you try to make a vector shrink to a capacity greater than its current capacity.