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https://github.com/go-gitea/gitea
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35 lines
1.4 KiB
Go
35 lines
1.4 KiB
Go
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/*
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Package merkletrie provides support for n-ary trees that are at the same
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time Merkle trees and Radix trees (tries).
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Git trees are Radix n-ary trees in virtue of the names of their
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tree entries. At the same time, git trees are Merkle trees thanks to
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their hashes.
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This package defines Merkle tries as nodes that should have:
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- a hash: the Merkle part of the Merkle trie
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- a key: the Radix part of the Merkle trie
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The Merkle hash condition is not enforced by this package though. This
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means that the hash of a node doesn't have to take into account the hashes of
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their children, which is good for testing purposes.
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Nodes in the Merkle trie are abstracted by the Noder interface. The
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intended use is that git trees implements this interface, either
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directly or using a simple wrapper.
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This package provides an iterator for merkletries that can skip whole
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directory-like noders and an efficient merkletrie comparison algorithm.
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When comparing git trees, the simple approach of alphabetically sorting
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their elements and comparing the resulting lists is too slow as it
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depends linearly on the number of files in the trees: When a directory
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has lots of files but none of them has been modified, this approach is
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very expensive. We can do better by prunning whole directories that
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have not change, just by looking at their hashes. This package provides
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the tools to do exactly that.
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*/
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package merkletrie
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