compressutil

func DecompressStream ¶

func DecompressStream(r io.Reader) (compression.DecompressReadCloser, error)

DecompressStream is containerd's compression.DecompressStream: it detects whether r is uncompressed, gzip or zstd and returns its decompressed bytes, and the same for every stream. A zstd stream is decoded by a decoder reused from an earlier stream, which Close returns for the next one. Unlike containerd's, the decoder sizes its buffers to what the streams it decodes need: containerd's options allocate each of its block decoders' sequence buffer at the most a block can hold, 2.3 MB, for every stream, and a kept decoder holds all of them.