mirror of
https://github.com/ipfs/kubo.git
synced 2026-02-24 03:47:45 +08:00
aaf05db536
add comprehensive test suite for UnixFS CID determinism per IPIP-499: - verify exact HAMT threshold boundary for both estimation modes: - v0-2015 (links): sum(name_len + cid_len) == 262144 - v1-2025 (block): serialized block size == 262144 - verify HAMT triggers at threshold + 1 byte for both profiles - add all deterministic CIDs for cross-implementation testing also wires SizeEstimationMode through CLI/API, allowing Import.UnixFSHAMTSizeEstimation config to take effect. bumps boxo to ipfs/boxo@6707376 which aligns HAMT threshold with JS implementation (uses > instead of >=), fixing CID determinism at the exact 256 KiB boundary.
40 lines
1.5 KiB
Go
40 lines
1.5 KiB
Go
package testutils
|
|
|
|
import "math/bits"
|
|
|
|
// VarintLen returns the number of bytes needed to encode v as a protobuf varint.
|
|
func VarintLen(v uint64) int {
|
|
return int(9*uint32(bits.Len64(v))+64) / 64
|
|
}
|
|
|
|
// LinkSerializedSize calculates the serialized size of a single PBLink in a dag-pb block.
|
|
// This matches the calculation in boxo/ipld/unixfs/io/directory.go estimatedBlockSize().
|
|
//
|
|
// The protobuf wire format for a PBLink is:
|
|
//
|
|
// PBNode.Links wrapper tag (1 byte)
|
|
// + varint length of inner message
|
|
// + Hash field: tag (1) + varint(cidLen) + cidLen
|
|
// + Name field: tag (1) + varint(nameLen) + nameLen
|
|
// + Tsize field: tag (1) + varint(tsize)
|
|
func LinkSerializedSize(nameLen, cidLen int, tsize uint64) int {
|
|
// Inner link message size
|
|
linkLen := 1 + VarintLen(uint64(cidLen)) + cidLen + // Hash field
|
|
1 + VarintLen(uint64(nameLen)) + nameLen + // Name field
|
|
1 + VarintLen(tsize) // Tsize field
|
|
|
|
// Outer wrapper: tag (1 byte) + varint(linkLen) + linkLen
|
|
return 1 + VarintLen(uint64(linkLen)) + linkLen
|
|
}
|
|
|
|
// EstimateFilesForBlockThreshold estimates how many files with given name/cid lengths
|
|
// will fit under the block size threshold.
|
|
// Returns the number of files that keeps the block size just under the threshold.
|
|
func EstimateFilesForBlockThreshold(threshold, nameLen, cidLen int, tsize uint64) int {
|
|
linkSize := LinkSerializedSize(nameLen, cidLen, tsize)
|
|
// Base overhead for empty directory node (Data field + minimal structure)
|
|
// Empirically determined to be 4 bytes for dag-pb directories
|
|
baseOverhead := 4
|
|
return (threshold - baseOverhead) / linkSize
|
|
}
|