Improve docs on bip158 module

Make an effort to improve the rustdocs throughout the `bip158` module.
This commit is contained in:
Tobin C. Harding 2022-08-09 16:33:58 +10:00
parent 5cfe9169f5
commit 167ee8e72c
1 changed files with 48 additions and 38 deletions

View File

@ -60,12 +60,12 @@ use crate::internal_macros::write_err;
const P: u8 = 19;
const M: u64 = 784931;
/// Errors for blockfilter
/// Errors for blockfilter.
#[derive(Debug)]
pub enum Error {
/// missing UTXO, can not calculate script filter
/// Missing UTXO, cannot calculate script filter.
UtxoMissing(OutPoint),
/// some IO error reading or writing binary serialization of the filter
/// IO error reading or writing binary serialization of the filter.
Io(io::Error),
}
@ -97,7 +97,7 @@ impl From<io::Error> for Error {
}
}
/// a computed or read block filter
/// A block filter, as described by BIP 158.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct BlockFilter {
/// Golomb encoded filter
@ -105,7 +105,7 @@ pub struct BlockFilter {
}
impl FilterHash {
/// compute the filter header from a filter hash and previous filter header
/// Computes the filter header from a filter hash and previous filter header.
pub fn filter_header(&self, previous_filter_header: &FilterHeader) -> FilterHeader {
let mut header_data = [0u8; 64];
header_data[0..32].copy_from_slice(&self[..]);
@ -143,7 +143,7 @@ impl BlockFilter {
filter_hash.filter_header(previous_filter_header)
}
/// match any query pattern
/// Returns true if any query matches against this [`BlockFilter`].
pub fn match_any<'a, I>(&self, block_hash: &BlockHash, query: I) -> Result<bool, Error>
where
I: Iterator<Item = &'a [u8]>,
@ -152,7 +152,7 @@ impl BlockFilter {
filter_reader.match_any(&mut self.content.as_slice(), query)
}
/// match all query pattern
/// Returns true if all queries match against this [`BlockFilter`].
pub fn match_all<'a, I>(&self, block_hash: &BlockHash, query: I) -> Result<bool, Error>
where
I: Iterator<Item = &'a [u8]>,
@ -162,14 +162,14 @@ impl BlockFilter {
}
}
/// Compiles and writes a block filter
/// Compiles and writes a block filter.
pub struct BlockFilterWriter<'a, W> {
block: &'a Block,
writer: GcsFilterWriter<'a, W>,
}
impl<'a, W: io::Write> BlockFilterWriter<'a, W> {
/// Create a block filter writer
/// Creates a new [`BlockFilterWriter`] from `block`.
pub fn new(writer: &'a mut W, block: &'a Block) -> BlockFilterWriter<'a, W> {
let block_hash_as_int = block.block_hash().into_inner();
let k0 = endian::slice_to_u64_le(&block_hash_as_int[0..8]);
@ -178,7 +178,7 @@ impl<'a, W: io::Write> BlockFilterWriter<'a, W> {
BlockFilterWriter { block, writer }
}
/// Add output scripts of the block - excluding OP_RETURN scripts
/// Adds output scripts of the block to filter (excluding OP_RETURN scripts).
pub fn add_output_scripts(&mut self) {
for transaction in &self.block.txdata {
for output in &transaction.output {
@ -189,7 +189,7 @@ impl<'a, W: io::Write> BlockFilterWriter<'a, W> {
}
}
/// Add consumed output scripts of a block to filter
/// Adds consumed output scripts of a block to filter.
pub fn add_input_scripts<M>(&mut self, script_for_coin: M) -> Result<(), Error>
where M: Fn(&OutPoint) -> Result<Script, Error> {
for script in self.block.txdata.iter()
@ -204,24 +204,24 @@ impl<'a, W: io::Write> BlockFilterWriter<'a, W> {
Ok(())
}
/// Add arbitrary element to a filter
/// Adds an arbitrary element to filter.
pub fn add_element(&mut self, data: &[u8]) {
self.writer.add_element(data);
}
/// Write block filter
/// Writes the block filter.
pub fn finish(&mut self) -> Result<usize, io::Error> {
self.writer.finish()
}
}
/// Reads and interpret a block filter
/// Reads and interprets a block filter.
pub struct BlockFilterReader {
reader: GcsFilterReader
}
impl BlockFilterReader {
/// Create a block filter reader
/// Creates a new [`BlockFilterReader`] from `block_hash`.
pub fn new(block_hash: &BlockHash) -> BlockFilterReader {
let block_hash_as_int = block_hash.into_inner();
let k0 = endian::slice_to_u64_le(&block_hash_as_int[0..8]);
@ -229,7 +229,7 @@ impl BlockFilterReader {
BlockFilterReader { reader: GcsFilterReader::new(k0, k1, M, P) }
}
/// match any query pattern
/// Returns true if any query matches against this [`BlockFilterReader`].
pub fn match_any<'a, I, R>(&self, reader: &mut R, query: I) -> Result<bool, Error>
where
I: Iterator<Item = &'a [u8]>,
@ -238,7 +238,7 @@ impl BlockFilterReader {
self.reader.match_any(reader, query)
}
/// match all query pattern
/// Returns true if all queries match against this [`BlockFilterReader`].
pub fn match_all<'a, I, R>(&self, reader: &mut R, query: I) -> Result<bool, Error>
where
I: Iterator<Item = &'a [u8]>,
@ -248,19 +248,19 @@ impl BlockFilterReader {
}
}
/// Golomb-Rice encoded filter reader
/// Golomb-Rice encoded filter reader.
pub struct GcsFilterReader {
filter: GcsFilter,
m: u64
}
impl GcsFilterReader {
/// Create a new filter reader with specific seed to siphash
/// Creates a new [`GcsFilterReader`] with specific seed to siphash.
pub fn new(k0: u64, k1: u64, m: u64, p: u8) -> GcsFilterReader {
GcsFilterReader { filter: GcsFilter::new(k0, k1, p), m }
}
/// match any query pattern
/// Returns true if any query matches against this [`GcsFilterReader`].
pub fn match_any<'a, I, R>(&self, reader: &mut R, query: I) -> Result<bool, Error>
where
I: Iterator<Item = &'a [u8]>,
@ -304,7 +304,7 @@ impl GcsFilterReader {
Ok(false)
}
/// match all query pattern
/// Returns true if all queries match against this [`GcsFilterReader`].
pub fn match_all<'a, I, R>(&self, reader: &mut R, query: I) -> Result<bool, Error>
where
I: Iterator<Item = &'a [u8]>,
@ -350,12 +350,12 @@ impl GcsFilterReader {
}
}
// fast reduction of hash to [0, nm) range
/// Fast reduction of hash to [0, nm) range.
fn map_to_range(hash: u64, nm: u64) -> u64 {
((hash as u128 * nm as u128) >> 64) as u64
}
/// Colomb-Rice encoded filter writer
/// Golomb-Rice encoded filter writer.
pub struct GcsFilterWriter<'a, W> {
filter: GcsFilter,
writer: &'a mut W,
@ -364,7 +364,7 @@ pub struct GcsFilterWriter<'a, W> {
}
impl<'a, W: io::Write> GcsFilterWriter<'a, W> {
/// Create a new Gcs writer wrapping a generic writer, with specific seed to siphash
/// Creates a new [`GcsFilterWriter`] wrapping a generic writer, with specific seed to siphash.
pub fn new(writer: &'a mut W, k0: u64, k1: u64, m: u64, p: u8) -> GcsFilterWriter<'a, W> {
GcsFilterWriter {
filter: GcsFilter::new(k0, k1, p),
@ -374,14 +374,14 @@ impl<'a, W: io::Write> GcsFilterWriter<'a, W> {
}
}
/// Add some data to the filter
/// Adds data to the filter.
pub fn add_element(&mut self, element: &[u8]) {
if !element.is_empty() {
self.elements.insert(element.to_vec());
}
}
/// write the filter to the wrapped writer
/// Writes the filter to the wrapped writer.
pub fn finish(&mut self) -> Result<usize, io::Error> {
let nm = self.elements.len() as u64 * self.m;
@ -405,7 +405,7 @@ impl<'a, W: io::Write> GcsFilterWriter<'a, W> {
}
}
/// Golomb Coded Set Filter
/// Golomb Coded Set Filter.
struct GcsFilter {
k0: u64, // sip hash key
k1: u64, // sip hash key
@ -413,12 +413,12 @@ struct GcsFilter {
}
impl GcsFilter {
/// Create a new filter
/// Creates a new [`GcsFilter`].
fn new(k0: u64, k1: u64, p: u8) -> GcsFilter {
GcsFilter { k0, k1, p }
}
/// Golomb-Rice encode a number n to a bit stream (Parameter 2^k)
/// Golomb-Rice encodes a number `n` to a bit stream (parameter 2^k).
fn golomb_rice_encode<'a, W>(&self, writer: &mut BitStreamWriter<'a, W>, n: u64) -> Result<usize, io::Error>
where
W: io::Write,
@ -435,7 +435,7 @@ impl GcsFilter {
Ok(wrote)
}
/// Golomb-Rice decode a number from a bit stream (Parameter 2^k)
/// Golomb-Rice decodes a number from a bit stream (parameter 2^k).
fn golomb_rice_decode<R>(&self, reader: &mut BitStreamReader<R>) -> Result<u64, io::Error>
where
R: io::Read
@ -448,13 +448,13 @@ impl GcsFilter {
Ok((q << self.p) + r)
}
/// Hash an arbitrary slice with siphash using parameters of this filter
/// Hashes an arbitrary slice with siphash using parameters of this filter.
fn hash(&self, element: &[u8]) -> u64 {
siphash24::Hash::hash_to_u64_with_keys(self.k0, self.k1, element)
}
}
/// Bitwise stream reader
/// Bitwise stream reader.
pub struct BitStreamReader<'a, R> {
buffer: [u8; 1],
offset: u8,
@ -462,7 +462,7 @@ pub struct BitStreamReader<'a, R> {
}
impl<'a, R: io::Read> BitStreamReader<'a, R> {
/// Create a new BitStreamReader that reads bitwise from a given reader
/// Creates a new [`BitStreamReader`] that reads bitwise from a given `reader`.
pub fn new(reader: &'a mut R) -> BitStreamReader<'a, R> {
BitStreamReader {
buffer: [0u8],
@ -471,7 +471,17 @@ impl<'a, R: io::Read> BitStreamReader<'a, R> {
}
}
/// Read nbit bits
/// Reads nbit bits, returning the bits in a `u64` starting with the rightmost bit.
///
/// # Examples
/// ```
/// # use bitcoin::util::bip158::BitStreamReader;
/// # let data = vec![0xff];
/// # let mut input = data.as_slice();
/// let mut reader = BitStreamReader::new(&mut input); // input contains all 1's
/// let res = reader.read(1).expect("read failed");
/// assert_eq!(res, 1_u64);
/// ```
pub fn read(&mut self, mut nbits: u8) -> Result<u64, io::Error> {
if nbits > 64 {
return Err(io::Error::new(io::ErrorKind::Other, "can not read more than 64 bits at once"));
@ -492,7 +502,7 @@ impl<'a, R: io::Read> BitStreamReader<'a, R> {
}
}
/// Bitwise stream writer
/// Bitwise stream writer.
pub struct BitStreamWriter<'a, W> {
buffer: [u8; 1],
offset: u8,
@ -500,7 +510,7 @@ pub struct BitStreamWriter<'a, W> {
}
impl<'a, W: io::Write> BitStreamWriter<'a, W> {
/// Create a new BitStreamWriter that writes bitwise to a given writer
/// Creates a new [`BitStreamWriter`] that writes bitwise to a given `writer`.
pub fn new(writer: &'a mut W) -> BitStreamWriter<'a, W> {
BitStreamWriter {
buffer: [0u8],
@ -509,7 +519,7 @@ impl<'a, W: io::Write> BitStreamWriter<'a, W> {
}
}
/// Write nbits bits from data
/// Writes nbits bits from data.
pub fn write(&mut self, data: u64, mut nbits: u8) -> Result<usize, io::Error> {
if nbits > 64 {
return Err(io::Error::new(io::ErrorKind::Other, "can not write more than 64 bits at once"));
@ -527,7 +537,7 @@ impl<'a, W: io::Write> BitStreamWriter<'a, W> {
Ok(wrote)
}
/// flush bits not yet written
/// flush bits not yet written.
pub fn flush(&mut self) -> Result<usize, io::Error> {
if self.offset > 0 {
self.writer.write_all(&self.buffer)?;