Added BaudRate enum for termios #518
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src/sys/termios.rs
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| 10014 => BaudRate::B2500000, | ||
| 10015 => BaudRate::B3000000, | ||
| 10016 => BaudRate::B3500000, | ||
| 10017 => BaudRate::B4000000, |
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I'm pretty sure this and many of the other constants you define here are completely incorrect as, looking at the linux kernel source (https://github.com/torvalds/linux/blob/master/include/uapi/asm-generic/termbits.h#L128), the constants there are in octal. These numbers are decimal and, as such, every constant you reference here greater than 7 is wrong.
Since there is better testing infrastructure for all libc variants in the libc crate, I believe we should introduce the constants there and add the type-safe enumeration providing access to this constants in nix. That has been our basic approach. Since libc uses ctest, it will verify the correctness of the constants.
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Yup, my mistake on the octals. Good catch, thanks.
I will make the correction and push again while looking into libc
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Could we push the constants up to libc? Can happen after this PR. |
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Working on it (see rust-lang/libc#530). Just need to fixup a few more issues before it'll be merged. I'll rework the |
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Oh awesome. I was hoping to help but just found confusing facts. :/ |
New baud constants landed in rust-lang/libc#530, we'll use them.
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Updated to use the newly-landed baud constants from libc (rust-lang/libc#530). Any thoughts on adding tests to |
No, as with many things testing some of this stuff is a little tricky as there are not great devices in the kernel for doing all sorts of things. It might be possible to set/get the baud rate on a PTY, but I'm OK with merging this change without that. |
| B460800 => BaudRate::B460800, | ||
| #[cfg(any(target_os = "netbsd", target_os = "freebsd"))] | ||
| B921600 => BaudRate::B921600, | ||
| b @ _ => unreachable!("Invalid baud constant: {}", b), |
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I don't think this arm is necessary. The compiler should be able to reason about this branch not being reachable and generate a compile error if something is off (which is better than this runtime error).
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I think it needs to be there to cover all branch cases. speed_t is just an alias to something like c_uint so you need a catch-all case at the end to cover all possible values of c_uint.
For example, if you remove the similar case for the linux group of constants at line 452 you'll get the compile error:
Compiling nix v0.8.0 (file:///home/zac/repos/rust/nix)
error[E0004]: non-exhaustive patterns: `_` not covered
--> /home/zac/repos/rust/nix/src/sys/termios.rs:420:23
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419 | match s {
| ^ pattern `_` not covered
error: aborting due to previous error
error: Could not compile `nix`.
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@homu r+ |
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📌 Commit 8b6242e has been approved by |
Added BaudRate enum for termios Issue #514 Does not provide `BaudRate::EXTA` or `BaudRate::EXTB` constants. These seem to alias to `B19200` and `B38400` respectively and so break the 1:1 mapping needed by `From`. I don't know their historic use.
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💔 Test failed - status |
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@homu retry |
Added BaudRate enum for termios Issue #514 Does not provide `BaudRate::EXTA` or `BaudRate::EXTB` constants. These seem to alias to `B19200` and `B38400` respectively and so break the 1:1 mapping needed by `From`. I don't know their historic use.
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☀️ Test successful - status |
Issue #514
Does not provide
BaudRate::EXTAorBaudRate::EXTBconstants. These seem to alias toB19200andB38400respectively and so break the 1:1 mapping needed byFrom. I don't know their historic use.