Add safe boolean transmutation module #11
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- add error reason for invalid values (should be refactored in next major release) - add guarded_transmute_bool_* variants which check for valid boolean values - add respective tests
Enet4
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src/bool.rs
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| #[inline] | ||
| fn bytes_are_bool(v: &[u8]) -> bool { | ||
| let sizeof_bool: usize = align_of::<bool>(); | ||
| for c in v.chunks(sizeof_bool).filter(|c| c.len() == sizeof_bool) { |
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What is rustfmt, amirite?
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Ain't nobody got time fo' that. $ rustfmt src/bool.rs
src/bool.rs
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| fn bytes_are_bool(v: &[u8]) -> bool { | ||
| let sizeof_bool: usize = align_of::<bool>(); | ||
| for c in v.chunks(sizeof_bool).filter(|c| c.len() == sizeof_bool) { | ||
| let (l, r) = c.split_at(sizeof_bool - 1); |
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The entirety of these functions is the same, apart from picking {L,M}SB. I feel like this would work as well, and better express what's happening:
let (msbs, lsb) = if cfg!(target_endian = "little") {
(c[1..], c)
} else {
c.split_at(sizeof_bool - 1)
};
if lsb[0] > 1 || msbs.iter().any(|x| *x != 0) {Also, you have an unhealthy obsession with naming verbols for that they are rather than for what they represent (l, r) mean naught, (l, m) or (lsb, msb) or sth would be 👍er.
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Ok, I took care of that. Glad the compiler's smart enough to optimize the if-else statement.
That last bit's subjective, but fine. I improved the variable naming as well.
src/lib.rs
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| //! | ||
| //! Those functions are exactly as safe as the data passed to them - creating a null pointer, | ||
| //! The base functions in this crate are not inherently safe, but just guarded against common simple mistakes | ||
| //! (like trying to create an 8-byte type from 7 bytes. |
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🎵 You missed a paren and you liked it 🎵
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🎵 I've got a lovely bunch of parentheses. 🎵
🎵 There they are, in a new commit. 🎵
src/lib.rs
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| @@ -76,7 +79,8 @@ pub use self::error::{ErrorReason, Error}; | |||
| pub use self::pod::{PodTransmutable, guarded_transmute_pod_many_permissive, guarded_transmute_pod_vec_permissive, guarded_transmute_pod_many_pedantic, | |||
| guarded_transmute_pod_pedantic, guarded_transmute_pod_vec_pedantic, guarded_transmute_pod_many, guarded_transmute_pod, | |||
| guarded_transmute_pod_vec}; | |||
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| pub use self::bool::{guarded_transmute_bool_permissive, guarded_transmute_bool_pedantic, | |||
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Are these sorted from longest to shortest?
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Released in |
This PR is actually a bit tricky, and contains things that maybe I could reconsider before merging. Currently Rust does not specify the size of
bool, which in turn leads to the theoretical possibility ofboolsbeing larger than one byte. In practice though, this doesn't happen. So right now I made the actual implementation generic over any sizebool, but made the tests assume that they're 1-byte sized. ¯\_(ツ)_/¯This also adds a new
InvalidValueserror reason. It is not exactly for size guard errors, but making heavier modifications to the error type requires a breaking change, which I have plans to do later in order to deal with #9.