install: implement copying from streams

[DaringCuteSeal]

This PR resolves #5080 and #4387 by copying cat's logic to copy from stream to a file.

However, I'm not sure about testing the cases for each stream type (other than standard input which I had provided in the test). I think it's better to be done in a future refactor where the logic for copying files (and streams) are combined into a single common utility.

[DaringCuteSeal]

yikes, seems like it's failing on Android. i'll look into that

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/tail/inotify-dir-recreate (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/timeout/timeout (fails in this run but passes in the 'main' branch)

[github-actions]

GNU testsuite comparison:

Skipping an intermittent issue tests/timeout/timeout (passes in this run but fails in the 'main' branch)

[github-actions]

GNU testsuite comparison:

Skipping an intermittent issue tests/timeout/timeout (passes in this run but fails in the 'main' branch)

[DaringCuteSeal]

okay fixed the unit test, the Android emulator seem to have /dev/stdin missing so I used /dev/fd/0 instead. should be good now

[DaringCuteSeal]

oh yeah forgot to ask again. are there anything else i need to add or remove?

[sylvestre]

looks good to me :)
Could we refactor this code to share it with cat?

[DaringCuteSeal]

Could we refactor this code to share it with cat?

Maybe we put splice.rs inside uucore. That good?

[DaringCuteSeal]

@sylvestre hey i'd love this to get merged since this bug is literally making my kernel disappear after every kernel upgrade 🤣

the pattern install /dev/stdin seem to be a lot more common than i thought--it's also part of Arch Linux's pacman hook for the Linux kernel packages.

I will look into squashing stream-copying functions into uucore--maybe also using it for cp since as of now it doesn't support copying special files (differs from GNU's coreutils).

[sylvestre]

Yeah
Sorry, I was waiting for this :) thanks

[sylvestre]

i guess you noticed that a few jobs are failing :)

[DaringCuteSeal]

i guess you noticed that a few jobs are failing :)

sorry, dont have like 10 virtual machines yet to check my code :} are CI checks discouraged here?

also for the gazillion commits, i will squash them together

[sylvestre]

nope, this is fine :)

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/timeout/timeout (fails in this run but passes in the 'main' branch)

[sylvestre]

once it will be ready to be merged, it would be nice to separate the uucore changes into a separate PR to make the change more atomic
thanks :)

[DaringCuteSeal]

once it will be ready to be merged, it would be nice to separate the uucore changes into a separate PR to make the change more atomic

Sure

[DaringCuteSeal]

@sylvestre the newly made splice module depends on the pipes module from uucore, how do i add to its dependency??

[sylvestre]

in the feature - features = ["splice"] } ?

[DaringCuteSeal]

uh, i'm assuming you mean for each of the utilities? or am i misunderstanding something? i did have that but for some reason i can't pass the FreeBSD tests

[sylvestre]

what is the error message ?

[DaringCuteSeal]

     Compiling uucore v0.0.28 (/home/runner/work/coreutils/coreutils/src/uucore)
  error[E0432]: unresolved imports `crate::pipes::splice`, `crate::pipes::splice_exact`
    --> src/uucore/src/lib/features/splice.rs:18:26
     |
  18 | use crate::pipes::{pipe, splice, splice_exact};
     |                          ^^^^^^  ^^^^^^^^^^^^ no `splice_exact` in `features::pipes`
     |                          |
     |                          no `splice` in `features::pipes`
     |
     = help: consider importing this module instead:
             crate::features::splice
  note: found an item that was configured out
    --> src/uucore/src/lib/features/pipes.rs:38:8
     |
  38 | pub fn splice(source: &impl AsFd, target: &impl AsFd, len: usize) -> Result<usize> {
     |        ^^^^^^
  note: the item is gated here
    --> src/uucore/src/lib/features/pipes.rs:37:1
     |
  37 | #[cfg(any(target_os = "linux", target_os = "android"))]
     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  note: found an item that was configured out
    --> src/uucore/src/lib/features/pipes.rs:48:8
     |
  48 | pub fn splice_exact(source: &impl AsFd, target: &impl AsFd, len: usize) -> Result<()> {
     |        ^^^^^^^^^^^^
  note: the item is gated here
    --> src/uucore/src/lib/features/pipes.rs:47:1
     |
  47 | #[cfg(any(target_os = "linux", target_os = "android"))]
     | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  
  For more information about this error, try `rustc --explain E0432`.

this help is also misleading since that's just itself :p

     = help: consider importing this module instead:
             crate::features::splice

i dont think i understand how rust crates work lol

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/timeout/timeout (fails in this run but passes in the 'main' branch)

[DaringCuteSeal]

nvm works now. my bad, i wrote unix instead of linux & android

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/timeout/timeout (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/tail/inotify-dir-recreate (passes in this run but fails in the 'main' branch)

[DaringCuteSeal]

i'm opening separate PRs i guess

[sylvestre]

yeah, it will help with the review, thanks :)