Port _CShims UUID to Swift #129
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| } | ||
| if res != 0 { | ||
| return nil | ||
| public init?(version: Version = .v4, uuidString string: __shared String) { |
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This would be an ABI breakage, since we're removing the previous initializer.
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That makes sense, thanks for letting me know Tony.
I restored the original initializers in c3cc89c, however I also understand that the changes in this PR are something that the team aren't ready to look at yet.
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One interesting security feature of our UUID implementation is that it is designed to do its work in constant time regardless of the content of the UUID. e.g., for equality checking. This is done in order to defeat timing attacks. We would need to verify we keep that behavior with a new implementation. |
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| static func v4_parse(uuidString string: __shared String) -> uuid_t? { | ||
| let components = string |
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Based on #129 (comment), one obvious optimization we can do here is to guard against string.count. However, both String.count and String.UTF8View.count is not O(1), so I guess we should parse the string manually and throw if it’s malformed, including too short or too long?
This is a spike for my own learning to see what's involved in removing the C-backed UUID implementation in favour of a Swift version.
I'm happy to revise this, as I realise that the implementation of some of this isn't ideal.