bitar 0.14.0

bita archive utilities
Documentation 
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/*
  Note: When editing this file, delete `src/chunk_dictionary.rs`
  and run `cargo build` to have the buildscript regenerate it.
  `protoc` needs to be in your PATH.
 */

syntax = "proto3";

package chunk_dictionary;

message ChunkDescriptor {
  // Hash of (uncompressed) chunk
  bytes checksum = 1;

  // Chunk data placement in archive.
  // If the archive_size = source_size then the chunk is uncompresed.
  uint32 archive_size = 3;
  uint64 archive_offset = 4;

  // Size of uncompressed chunk data
  uint32 source_size = 5;
}

message ChunkerParameters {
  enum ChunkingAlgorithm {
    BUZHASH = 0;
    ROLLSUM = 1;
    FIXED_SIZE = 2;
  }
  uint32 chunk_filter_bits = 1;
  uint32 min_chunk_size = 2;
  // max_chunk_size is also the fixed chunk size when FIXED_SIZE is set
  uint32 max_chunk_size = 3;
  uint32 rolling_hash_window_size = 4;
  uint32 chunk_hash_length = 5;
  ChunkingAlgorithm chunking_algorithm = 6;
}

message ChunkCompression {
  enum CompressionType {
    NONE = 0;
    LZMA = 1;
    ZSTD = 2;
    BROTLI = 3;
  }
  CompressionType compression = 2;
  uint32 compression_level = 3;
}

message ChunkDictionary {
  // Dictionary was created with this version
  string application_version = 1;

  // Hash of the source file
  bytes source_checksum = 2;

  // Total size of the source file
  uint64 source_total_size = 3;

  // Chunker parameters used when building archive
  ChunkerParameters chunker_params = 4;

  // Chunk compression used for all chunks in archive
  ChunkCompression chunk_compression = 5;

  // Array of chunk descriptor indexes describing howto rebuild the source
  repeated uint32 rebuild_order = 6;

  // Chunk descriptors in order of first occurence in source file
  repeated ChunkDescriptor chunk_descriptors = 7;

  // Custom key-value-pair metadata to store with the dictionary
  map<string, bytes> metadata = 8;
}