Crate btlib

This crate contains the core structs and traits used by Blocktree. The crypto module contains all of the cryptographic primitives used to implement this system. Most of the functionality for accessing blocks is defined by the Block trait. The BlockMeta struct is the type which implements block metadata.

Re-exports

• pub use error::Error;
• pub use error::Result;

Modules

• accessor
  This module contains the Accessor type.
• atomic_file
  This module exports the AtomicFile struct, which is used to synchronize access to a file.
• buf_reader
  This module contains the BufReader type.
• collections
  A collection of collection types.
• config_helpers
  This module contains functions which are useful for configuring applications.
• crypto
  This module contains types providing the cryptographic primitives necessary to implement Blocktree.
• drop_trigger
  Contains the DropTrigger type.
• error
  This module defines the Error and Result types used in this crate. It also defines macros, bterr! and btensure!. The first accepts either a type which is StdError + Send + Sync + 'static or the same arguments as format!, allowing you to create one-off string errors. btensure takes a boolean expression as its first argument, and its remaining arguments are the same as those to bterr.
• log
  Helpers for configuring logging.
• sectored_buf
  Contains the SectoredBuf type.

Macros

• btensure
  Ensures that an expression evaluates to true, and if it does’nt, returns an error.
• bterr
  Creates a new Error, which contains a stacktrace captured at the point where this macro was evaluated.
• suppress_err_if_non_zero
  Attempts to unwrap the given result. If the result is an error and the given count is positive, then the error is logged and Ok($count) is returned. If the result is an error and count is zero, then the Err variant is returned containing it.

Structs

• AuthzAttrs
  Attributes associated with a principal which are used for authorization decisions.
• BlockId
  A unique identifier for a block.
• BlockMeta
  Signed metadata associated with a block.
• BlockMetaBody
  This struct contains all of the metadata fields associated with a block, except for its signature. Since this struct implements Serialize, this allows for convenient signature calculations.
• BlockMetaSecrets
  Metadata that is encrypted.
• BlockOpenOptions
  Describes how to open a block, including the inner stream from which the block can be read and the credentials to use to open it.
• BlockPath
  An owned identifier for a block in a tree.
• BlockPathGen
  A generic block path.
• BlockPathRef
  A reference to a block path.
• BlockStream
  A stream which is responsible for managing the metadata associated with a block, including validating and authenticating it. This type shouldn’t be instantiated direction, instead a BlockOpenOptions struct is used.
• Cursor
  A wrapper around positioned_io::SizeCursor which implements Split.
• Directory
  This is the body contained in directory blocks.
• Epoch
  An instant in time represented by the number of seconds since January 1st 1970, 00:00:00 UTC.
• Fragment
  Fragments are created from blocks using Erasure Encoding and stored with other nodes in the network to provide availability and redundancy of data.
• FragmentRecord
  Keeps track of which principal is storing a fragment.
• FragmentSerial
  The serial number of a block fragment.
• IssuedProcRec
  A record which stores the authorization attributes, credentials, writecap, and IP address of a process.
• Principal
  An identifier for a security principal, which is any entity that can be authenticated.
• Readcap
  An envelopment of a key, which is tagged with the principal who the key is meant for.
• RelBlockPath
  Represents a relative block path.
• ServerRecord
  Structure for keeping track of server information in a directory.
• Writecap
  Verifies that a principal is authorized to write blocks in a tree.
• WritecapBody

Enums

• BlockError
• BlockPathError
  Errors which can occur when converting a string to a Path.
• DirEntry
• DirEntryKind
  Auto-generated discriminant enum variants
• ProcRec
  Structure stored in process blocks for keeping track of process credentials and location.

Constants

• EMPTY_SLICE
  A zero length slice of bytes.
• EXPECTED_IO_BLOCK
  The expected size of the IO blocks for the file system. This is used to calculate SECTOR_SZ_DEFAULT.
• IO_BLOCKS_PER_SECTOR
  The number of IO blocks in each sector.
• SECTOR_SZ_DEFAULT
  The default sector size to use for new blocks.
• SECTOR_U64_DEFAULT
  SECTOR_SZ_DEFAULT converted to a u64.

Traits

• Block
  THE BLOCK TRAIT
• BlockAccessor
• BlockReader
• Decompose
• FlushMeta
• MetaAccess
  Trait for accessing the metadata associated with a block.
• MetaReader
• Positioned
  Trait for streams which can efficiently and infallibly return their current position.
• Principaled
  Trait for types which are owned by a Principal.
• ReadDual
  The Read trait requires the caller to supply the buffer to be read into. This trait is its dual in the sense that the trait implementor is expected to supply its own buffer, which a Write instance is given. This can be used to avoid copying in cases where the trait implementor is already buffering data, so it can give a reference to this buffer to the caller (for example in SectoredBuf)
• Sectored
• SeekFromExt
• SizeExt
• Split
• TryCompose
• TrySeek
• WriteDual
• WriteInteg
  A version of the WriteAt trait, which allows integrity information to be supplied when flushing.
• ZeroExtendable
  Trait for types which can be extended with zero byes.

Type Definitions

• ConcreteBlock
  The composition of a BlockStream in a MerkleStream.
• FileBlock
  A ConcreteBlock which stores its data in a file in the filesystem.
• Inode
  The type used to identify blocks.