Calling `Read::read` or `Write::write` without checking the returned
`usize` value is almost always an error. Example code in the
documentation should demonstrate how to use the return value correctly.
Otherwise, people might copy the example code thinking that it is okay
to "fire and forget" these methods.
fs::copy() unix: set file mode early
A convenience method like fs::copy() should try to prevent pitfalls a
normal user doesn't think about.
In case of an empty umask, setting the file mode early prevents
temporarily world readable or even writeable files,
because the default mode is 0o666.
In case the target is a named pipe or special device node, setting the
file mode can lead to unwanted side effects, like setting permissons on
`/dev/stdout` or for root setting permissions on `/dev/null`.
copy_file_range() returns EINVAL, if the destination is a FIFO/pipe or
a device like "/dev/null", so fallback to io::copy, too.
Fixes: https://github.com/rust-lang/rust/issues/26933
Fixed: https://github.com/rust-lang/rust/issues/37885
Include id in Thread's Debug implementation
Since Rust 1.19.0, `id` is a stable method, so there is no reason to not include it in Debug implementation.
Add `Default` to `std::alloc::System`
`System` is a unit struct, thus, it can be constructed without any additional information. Therefore `Default` is a noop. However, in generic code, a `T: Default` may happen as in
```rust
#[derive(Default)]
struct Foo<A> {
allocator: A
}
```
Does this need a feature gate?
Should I also add `PartialEq/Eq/PartialOrd/Ord/Hash`?
Simplify checked_duration_since
This follows the same design as we updated to in #56490. Internally, all the system specific time implementations are checked, no panics. Then the panicking publicly exported API can just call the checked version of itself and make do with a single panic (`expect`) at the top.
Since the internal sys implementations are now checked, this gets rid of the extra `if self >= &earlier` check in `checked_duration_since`. Except likely making the generated machine code simpler, it also reduces the algorithm from "Check panic condition -> call possibly panicking method" to just "call non panicking method".
Added two test cases:
* Edge case: Make sure `checked_duration_since` on two equal `Instant`s produce a zero duration, not a `None`.
* Most common/intended usage: Make sure `later.checked_duration_since(earlier)`, returns an expected value.
SGX target: fix std unit tests
This fixes some tests and some code in the SGX sys implementation to make the `std` unit test suite pass.
#59009 must be merged first.
A convenience method like fs::copy() should try to prevent pitfalls a
normal user doesn't think about.
In case of an empty umask, setting the file mode early prevents
temporarily world readable or even writeable files,
because the default mode is 0o666.
In case the target is a named pipe or special device node, setting the
file mode can lead to unwanted side effects, like setting permissons on
`/dev/stdout` or for root setting permissions on `/dev/null`.
copy_file_range() returns EINVAL, if the destination is a FIFO/pipe or
a device like "/dev/null", so fallback to io::copy, too.
Use `fcopyfile` on MacOS instead of `copyfile`.
Fixes: https://github.com/rust-lang/rust/issues/26933
Fixed: https://github.com/rust-lang/rust/issues/37885
Rollup of 18 pull requests
Successful merges:
- #59106 (Add peer_addr function to UdpSocket)
- #59170 (Add const generics to rustdoc)
- #59172 (Update and clean up several parts of CONTRIBUTING.md)
- #59190 (consistent naming for Rhs type parameter in libcore/ops)
- #59236 (Rename miri component to miri-preview)
- #59266 (Do not complain about non-existing fields after parse recovery)
- #59273 (some small HIR doc improvements)
- #59291 (Make Option<ThreadId> no larger than ThreadId, with NonZeroU64)
- #59297 (convert field/method confusion help to suggestions)
- #59304 (Move some bench tests back from libtest)
- #59309 (Add messages for different verbosity levels. Output copy actions.)
- #59321 (Unify E0109, E0110 and E0111)
- #59322 (Tweak incorrect escaped char diagnostic)
- #59323 (use suggestions for "enum instead of variant" error)
- #59327 (Add NAN test to docs)
- #59329 (cleanup: Remove compile-fail-fulldeps directory again)
- #59347 (Move one test from run-make-fulldeps to ui)
- #59360 (Add tracking issue number for `seek_convenience`)
Failed merges:
r? @ghost
Add peer_addr function to UdpSocket
Fixes#59104
This is my first pull request to Rust, so opening early for some feedback.
My biggest question is: where do I add tests?
Any comments very much appreciated!
Add provided methods `Seek::{stream_len, stream_position}`
This adds two new, provided methods to the `io::Seek` trait:
- `fn stream_len(&mut self) -> Result<u64>`
- `fn stream_position(&mut self) -> Result<u64>`
Both are added for convenience and to improve readability in user code. Reading `file.stream_len()` is much better than to manually seek two or three times. Similarly, `file.stream_position()` is much more clear than `file.seek(SeekFrom::Current(0))`.
You can find prior discussions [in this internals thread](https://internals.rust-lang.org/t/pre-rfc-idea-extend-io-seek-with-convenience-methods-with-e-g-stream-len/9262). I think I addressed all concerns in that thread.
I already wrote three RFCs to add a small new API to libstd but I noticed that many public changes to libstd happen without an RFC. So I figured I can try opening a PR directly without going through RFCs first. After all, we do have rfcbot here too. If you think this change is too big to merge without an RFC, I can still close this PR and write an RFC.
Add new test case for possible bug in BufReader
When reading a large chunk from a BufReader, if all the bytes from the buffer have been already consumed, the internal buffer is bypassed entirely. However, it is not invalidated, and it's possible to access its contents using the `seek_relative` method, because it tries to reuse the existing buffer.
