std::net: Ipv4Addr and Ipv6Addr improvements
Picking this up again from my previous PR: https://github.com/rust-lang/rust/pull/56050
Related to: https://github.com/rust-lang/rust/issues/27709
Fixes: https://github.com/rust-lang/rust/issues/57558
- add `add Ipv4Addr::is_reserved()`
- [X] implementation
- [X] tests
- add `Ipv6Addr::is_unicast_link_local_strict()` and update `Ipv6Addr::is_unicast_link_local()` documentation
- [X] implementation
- [X] test
- add `Ipv4Addr::is_benchmarking()`
- [X] implementation
- [X] test
- add `Ipv4Addr::is_ietf_protocol_assignment()`
- [X] implementation
- [X] test
- add `Ipv4Addr::is_shared()`
- [X] implementation
- [x] test
- fix `Ipv4Addr:is_global()`
- [X] implementation
- [x] test
- [X] refactor the tests for IP properties. This makes the tests more verbose, but using macros have two advantages:
- it will now be easier to add tests for all the new methods
- we get clear error messages when a test is failing. For instance:
```
---- net::ip::tests::ip_properties stdout ----
thread '<unnamed>' panicked at 'assertion failed: !ip!("fec0::").is_global()', src/libstd/net/ip.rs:2036:9
```
Whereas previously it was something like
```
thread '<unnamed>' panicked at 'assertion failed: `(left == right)`
left: `true`,
right: `false`', libstd/net/ip.rs:1948:13
```
-----------------------
# Ongoing discussions:
## Should `Ipv4Addr::is_global()` return `true` or `false` for reserved addresses?
Reserved addresses are addresses that are matched by `Ipv4Addr::is_reserved()`.
@the8472 [pointed out](https://github.com/rust-lang/rust/pull/60145#issuecomment-485458319) that [RFC 4291](https://tools.ietf.org/html/rfc4291#section-2.4) says IPv6 reserved addresses should be considered global:
```
Future specifications may redefine one or more sub-ranges of the
Global Unicast space for other purposes, but unless and until that
happens, implementations must treat all addresses that do not start
with any of the above-listed prefixes as Global Unicast addresses.
```
We could extrapolate that this should also be the case for IPv4. However, it seems that [IANA considers them non global](https://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xhtml) (see [my comment](https://github.com/rust-lang/rust/pull/60145#issuecomment-485713270))
### Final decision
There seems to be a consensus that reserved addresses have a different meaning for IPv4 and IPv6 ([comment1](https://github.com/rust-lang/rust/pull/60145#issuecomment-485963789) [comment2](https://github.com/rust-lang/rust/pull/60145#issuecomment-485944582), so we can consider that RFC4291 does not apply to IPv4, and that reserved IPv4 addresses are _not_ global.
## Should `Ipv6Addr::is_unicast_site_local()` exist?
@pusateri [noted](https://github.com/rust-lang/rust/pull/60145#issuecomment-485507515) that site-local addresses have been deprecated for a while by [RFC 3879](https://tools.ietf.org/html/rfc3879) and new implementations _must not_ support them. However, since this method is stable, removing does not seem possible. This kind of situation is covered by the RFC which stated that existing implementation _may_ continue supporting site-local addresses.
### Final decision
Let's keep this method. It is stable already, and the RFC explicitly states that existing implementation may remain.
---------
Note: I'll be AFK from April 27th to May 11th. Anyone should feel free to pick this up if the PR hasn't been merged by then. Sorry for dragging that for so long already.
Fix intra-doc link resolution failure on re-exporting libstd
Currently, re-exporting libstd items as below will [occur a lot of failures](https://gist.github.com/taiki-e/e33e0e8631ef47f65a74a3b69f456366).
```rust
pub use std::*;
```
Until the underlying issue (#56922) fixed, we can fix that so they don't propagate to downstream crates.
Related: https://github.com/rust-lang/rust/pull/56941 (That PR fixed failures that occur when re-exporting from libcore to libstd.)
r? @QuietMisdreavus
This renames `std::io::IoVec` to `std::io::IoSlice` and
`std::io::IoVecMut` to `std::io::IoSliceMut`, and stabilizes
`std::io::IoSlice`, `std::io::IoSliceMut`,
`std::io::Read::read_vectored`, and `std::io::Write::write_vectored`.
Closes#58452
See @the8472 comment's on Github:
https://github.com/rust-lang/rust/pull/60145#issuecomment-485424229
> I don't think is_reserved including ranges marked for future use is
> a good idea since those future uses may be realized at at some point
> and then old software with is_reserved filters may have false
> positives. This is not a hypothetical concern, such issues have been
> encountered before when IANA assigned previously reserved /8 address
> blocks.
As per @therealbstern's comment[0]:
The implementation of Ipv4::is_global is not complete, according to the
IANA IPv4 Special-Purpose Address Registry.
- It compares the address to 0.0.0.0, but anything in 0.0.0.0/8
should not be considered global.
- 0/8 is not global and is currently forbidden because
some systems used to treat it as the local network.
- The implementation of Ipv4::is_unspecified is correct.
0.0.0.0 is the unspecified address.
- It does not examine 100.64.0.0/10, which is "Shared Address
Space" and not global.
- Ditto 192.0.0.0/24 (IETF Protocol Assignments), except for
192.0.0.9/32 and 192.0.0.10/32, which are carved out as
globally reachable.
- 198.18.0.0/15 is for "Benchmarking" and should not be globally
reachable.
- 240.0.0.0/4 is reserved and not currently reachable
RFC 4291 is a little unclear about what is a unicast link local address.
According to section 2.4, the entire fe80::/10 range is reserved for
these addresses, but section 2.5.3 defines a stricter format for such
addresses.
After a discussion[0] is has been decided to add a different method for
each definition, so this commit:
- renames is_unicast_link_local() into is_unicast_link_local_strict()
- relaxed the check in is_unicast_link_local()
[0]: https://github.com/rust-lang/rust/issues/27709#issuecomment-400370706
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.
This commit deletes the `connect_timeout_unbound` test from the standard
library which, unfortunately, is by definition eventually going to be a
spuriously failing test. There's no way to reserve a port as unbound so
we can rely on ecosystem testing for this feature for now.
Closes#52590
Add vectored read and write support
This functionality has lived for a while in the tokio ecosystem, where
it can improve performance by minimizing copies.
r? @alexcrichton
Explain a panic in test case net::tcp::tests::double_bind
Those who try to build libstd on the Windows Subsystem for Linux experience a single failing test, where the point of failure is an explicit but anonymous panic, as reported in https://github.com/rust-lang/rust/issues/49367
This commit somewhat explains why and allows diagnosing a little.
There are two big categories of changes in here
- Removing lifetimes from common traits that can essentially never user a lifetime from an input (particularly `Drop` & `Debug`)
- Forwarding impls that are only possible because the lifetime doesn't matter (like `impl<R: Read + ?Sized> Read for &mut R`)
I omitted things that seemed like they could be more controversial, like the handful of iterators that have a `Item: 'static` despite the iterator having a lifetime or the `PartialEq` implementations where the flipped one cannot elide the lifetime.
