More arithmetic operations (and tests) for PrefixSize #687
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We based our implementation on the addition of a PrefixSize and a u128, making all other cases return a PrefixSize::Overflow, but the addition between two PrefixSize objects needs to take another corner case into account: for PrefixSize::U128(0) + PrefixSize::Ipv6MaxAddrs, the result is not an overflow but PrefixSize::Ipv6MaxAddrs. Found while working on fuzzing tests for another component. Signed-off-by: Quentin Monnet <[email protected]>
Signed-off-by: Quentin Monnet <[email protected]>
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Implement trait SubAssign for PrefixSize, given that we already suppot the Sub trait. Speaking of, we also adjust our implementation of the Sub trait for PrefixSize - PrefixSize, so that subtracting Overflow from something triggers an overflow panic (instead of returning Overflow). Also make sure that we panic and never wrap in case of subtaction overflow (it doesn't make sense to wrap around in case of PrefixSize objects). Signed-off-by: Quentin Monnet <[email protected]>
We have Add, Sub, and their -Assign variants. Let's support multiplication for prefix sizes. This can be handy when growing or splitting prefixes and comparing their sizes. Signed-off-by: Quentin Monnet <[email protected]>
This is useful when manipulating prefixes, to easily obtain the size of a half-prefix, for example. Signed-off-by: Quentin Monnet <[email protected]>
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Signed-off-by: Quentin Monnet <[email protected]>
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mvachhar
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Jul 11, 2025
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Improve implementations for
AddandSub, add implementations forMul,Div, and the -Assignvariants forPrefixSize. This should help with future work with prefix size manipulation.First commit is a fix.