Stop copying Strings into Arrays for SHA1 (#1413)
Stop copying Strings into Arrays for SHA1 (#1413)

Motivation:

Resolve #1409

Modifications:

Using withContiguousStorageIfAvailable if string.utf8 supports an internal representation in a form. Otherwise, fall back to use withUnsafeBufferPointer.

Result:

Save an allocation for each hash function update

apple/swift-nio,apple/swift-nio,apple/swift-nio,apple/swift-nio,apple/swift-nio