3 releases
0.1.16-alpha.0 | Apr 1, 2023 |
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0.1.12-alpha.0 | Jan 19, 2023 |
0.1.10-alpha.0 | Jan 18, 2023 |
#46 in #leveldb
461 downloads per month
Used in 66 crates
(via bitcoin-leveldb)
390KB
822 lines
bitcoinleveldb-coding
is a Rust crate that
provides encoding and decoding functions for
various data types used in the Bitcoin
system. This crate is part of a direct translation
from C++ to Rust of the Bitcoin Core, which means
that some of the function bodies may still be in
the process of translation. However, once the
translation process is complete, this system will
become testable.
Some of the tokens in this crate, such as
coding_varint32
, coding_varint64
, and
varint_length
, involve the encoding and decoding
of variable-length integers. These are useful for
efficiently storing and transmitting integers that
may have varying sizes. The encoding process
involves splitting the integer into 7-bit chunks,
with the high bit of each chunk set to 1 except
for the last chunk. The chunks are then stored in
a byte array in little-endian order. Decoding the
integer involves reversing this process.
Other tokens, such as coding_fixed32
,
coding_fixed64
, decode_fixed32
, and
decode_fixed64
, involve encoding and decoding
fixed-length integers. These are useful for
efficiently storing and transmitting integers that
have a fixed size.
There are also tokens related to encoding and
decoding strings, such as coding_strings
and
get_length_prefixed_slice
. These are useful for
storing and transmitting variable-length strings
in a compact and efficient way.
Overall, the bitcoinleveldb-coding
crate
provides useful encoding and decoding functions
for various data types used in the Bitcoin system,
making it a valuable tool for developers working
with Bitcoin-related data.
28> thanks -- could you teach me more about these encoding/decoding formats in the context of leveldb
Sure! In the context of LevelDB, these encoding and decoding formats are used for storing and retrieving key-value pairs in a compact and efficient way. Specifically, LevelDB uses a combination of variable-length integer encoding and length-prefixed strings to achieve this.
Variable-length integer encoding, implemented by
the coding_varint32
, coding_varint64
, and
varint_length
functions in the
bitcoinleveldb-coding
crate, is used to store
integer values that may have varying sizes. In
LevelDB, these integers are typically used as keys
to identify a specific value in the database. By
encoding these integers as variable-length
integers, LevelDB can store the integers using
fewer bytes than if they were encoded as
fixed-length integers.
Length-prefixed strings, implemented by the
get_length_prefixed_slice
and
put_length_prefixed_slice
functions in the
bitcoinleveldb-coding
crate, are used to store
string values in the database. In this encoding
format, a string is prefixed by its length, which
is encoded as a variable-length integer. This
allows LevelDB to efficiently store and retrieve
string values of varying lengths.
The coding_fixed32
, coding_fixed64
,
decode_fixed32
, and decode_fixed64
functions
in the bitcoinleveldb-coding
crate are used to
encode and decode fixed-length integers. While
these encoding formats are not used as frequently
in LevelDB as variable-length integer encoding and
length-prefixed strings, they are still useful for
efficiently storing and retrieving integer values
that have a fixed size.
Overall, these encoding and decoding formats are essential for efficient data storage and retrieval in LevelDB, and are therefore an important part of the LevelDB system.
Dependencies
~88MB
~848K SLoC