[Wip]Tentative add alloc::io module.

[lygstate]

At the current stage, just copy std::io into alloca::io and

• Remove the os related things such as std::io::stdio.
• Also convert all Error to string
• Add core:ctypes
• Use core::ctypes::iovec instead.

Get std::io to be an core::io component so that can be used by runtime implemenation.

Especially for posix libc implemenation in rust with

• syscall(Linux)
• win32 api (windows)
• syscall(osx)
• syscall(redox)
• ? (fedora)
  and so on.

This is for https://github.com/redox-os/relibc

Also for
https://github.com/rulibc/rulibc
The fork of relibc that act as an msvcrt/mingw/cygwin/msys2 alternative on win32

glibc/musl alternative on linux world.

redox support will alomost unchanged with the upstream Thttps://github.com/redox-os/relibc

And makes platform dependent IoSliceMut can be customized by the user
And give the default impl for windows/posix.

#36193
related

Depends on
rust-lang/project-error-handling#3
#77384

[rust-highfive]

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[jyn514]

This looks like a copy/paste of std::io to alloc::io. Unfortunately, this won't work because alloc is meant to work on platforms without an operating system and io depends on the operating system.

I recommend going through an RFC process or https://internals.rust-lang.org/ if you're interested in this change, but it will need a lot of design and a rationale for why it's useful. This PR as-is is unlikely to be merged.

[lygstate]

This looks like a copy/paste of std::io to alloc::io. Unfortunately, this won't work because alloc is meant to work on platforms without an operating system and io depends on the operating system.

I recommend going through an RFC process or https://internals.rust-lang.org/ if you're interested in this change, but it will need a lot of design and a rationale for why it's useful. This PR as-is is unlikely to be merged.

Thanks, this tentative, I have already removed the operating system part from alloc::io, I placed it under io because std::io depends on alloc, so I didn't place it under core::io.
The only part of alloc::io that are special are the iovec struct and I place it in the core::ctypes, it's seems other than windows platform, all other platform are the same, never mind what iovec it is, it's just a structure need to passed into operating system, so we just need to compatiable with the corresponding operating system

[bors]

☔ The latest upstream changes (presumably #76885) made this pull request unmergeable. Please resolve the merge conflicts.

Note that reviewers usually do not review pull requests until merge conflicts are resolved! Once you resolve the conflicts, you should change the labels applied by bors to indicate that your PR is ready for review. Post this as a comment to change the labels:

@rustbot modify labels: +S-waiting-on-review -S-waiting-on-author

[rust-log-analyzer]

The job mingw-check failed! Check out the build log: (web) (plain)

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Caused by:
  failed to open: /checkout/src/bootstrap/Cargo.lock

Caused by:
  Read-only file system (os error 30)
Build completed unsuccessfully in 0:00:37

[bors]

☔ The latest upstream changes (presumably #82249) made this pull request unmergeable. Please resolve the merge conflicts.

[Dylan-DPC-zz]

@lygstate can you resolve the conflicts?

[lygstate]

@Dylan-DPC Currently it's depends on #77384
after that merged, then this can be working on

[Dylan-DPC-zz]

closing this as this depends on a draft, which is going to take some time to get merged and it would probably be easier to open a fresh pr instead of solving all the conflicts that will accumulate by then.