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-rw-r--r--commitgraph/bloom/bloom.go3
-rw-r--r--commitgraph/bloom/constants.go8
-rw-r--r--commitgraph/bloom/contain.go25
-rw-r--r--commitgraph/bloom/errors.go5
-rw-r--r--commitgraph/bloom/filter.go26
-rw-r--r--commitgraph/bloom/key.go117
-rw-r--r--commitgraph/bloom/murmur.go127
-rw-r--r--commitgraph/bloom/settings.go50
8 files changed, 0 insertions, 361 deletions
diff --git a/commitgraph/bloom/bloom.go b/commitgraph/bloom/bloom.go
deleted file mode 100644
index 9653d595..00000000
--- a/commitgraph/bloom/bloom.go
+++ /dev/null
@@ -1,3 +0,0 @@
-// Package bloom provides a bloom filter implementation used for changed-path
-// filters in Git commit graphs.
-package bloom
diff --git a/commitgraph/bloom/constants.go b/commitgraph/bloom/constants.go
deleted file mode 100644
index 958e551e..00000000
--- a/commitgraph/bloom/constants.go
+++ /dev/null
@@ -1,8 +0,0 @@
-package bloom
-
-const (
- // DataHeaderSize is the size of the BDAT header in commit-graph files.
- DataHeaderSize = 3 * 4
- // DefaultMaxChange matches Git's default max-changed-paths behavior.
- DefaultMaxChange = 512
-)
diff --git a/commitgraph/bloom/contain.go b/commitgraph/bloom/contain.go
deleted file mode 100644
index 331b7687..00000000
--- a/commitgraph/bloom/contain.go
+++ /dev/null
@@ -1,25 +0,0 @@
-package bloom
-
-// MightContain reports whether the Bloom filter may contain the given path.
-//
-// Evaluated against the full path and each of its directory prefixes. A true
-// result indicates a possible match; false means the path definitely did not
-// change.
-func (f *Filter) MightContain(path []byte) (bool, error) {
- if len(f.Data) == 0 {
- return false, nil
- }
-
- keys, err := keyvec(path, f)
- if err != nil {
- return false, err
- }
-
- for i := range keys {
- if filterContainsKey(f, keys[i]) {
- return true, nil
- }
- }
-
- return false, nil
-}
diff --git a/commitgraph/bloom/errors.go b/commitgraph/bloom/errors.go
deleted file mode 100644
index fe38d1bc..00000000
--- a/commitgraph/bloom/errors.go
+++ /dev/null
@@ -1,5 +0,0 @@
-package bloom
-
-import "errors"
-
-var ErrInvalid = errors.New("bloom: invalid data")
diff --git a/commitgraph/bloom/filter.go b/commitgraph/bloom/filter.go
deleted file mode 100644
index 395dd5ce..00000000
--- a/commitgraph/bloom/filter.go
+++ /dev/null
@@ -1,26 +0,0 @@
-package bloom
-
-// Filter represents a changed-paths Bloom filter associated with a commit.
-//
-// The filter encodes which paths changed between a commit and its first
-// parent. Paths are expected to be in Git's slash-separated form and
-// are queried using a path and its prefixes (e.g. "a/b/c", "a/b", "a").
-type Filter struct {
- Data []byte
-
- HashVersion uint32
- NumHashes uint32
- BitsPerEntry uint32
- MaxChangePaths uint32
-}
-
-// NewFilter constructs one query-ready bloom filter from raw data/settings.
-func NewFilter(data []byte, settings Settings) Filter {
- return Filter{
- Data: data,
- HashVersion: settings.HashVersion,
- NumHashes: settings.NumHashes,
- BitsPerEntry: settings.BitsPerEntry,
- MaxChangePaths: settings.MaxChangePaths,
- }
-}
diff --git a/commitgraph/bloom/key.go b/commitgraph/bloom/key.go
deleted file mode 100644
index a15df904..00000000
--- a/commitgraph/bloom/key.go
+++ /dev/null
@@ -1,117 +0,0 @@
-package bloom
-
-import "codeberg.org/lindenii/furgit/internal/intconv"
-
-type key struct {
- hashes []uint32
-}
-
-func keyvec(path []byte, filter *Filter) ([]key, error) {
- if len(path) == 0 {
- return nil, nil
- }
-
- count := 1
-
- for _, b := range path {
- if b == '/' {
- count++
- }
- }
-
- keys := make([]key, 0, count)
-
- full, err := keyFill(path, filter)
- if err != nil {
- return nil, err
- }
-
- keys = append(keys, full)
-
- for i := len(path) - 1; i >= 0; i-- {
- if path[i] == '/' {
- k, err := keyFill(path[:i], filter)
- if err != nil {
- return nil, err
- }
-
- keys = append(keys, k)
- }
- }
-
- return keys, nil
-}
-
-func keyFill(path []byte, filter *Filter) (key, error) {
- const (
- seed0 = 0x293ae76f
- seed1 = 0x7e646e2c
- )
-
- var (
- h0 uint32
- h1 uint32
- err error
- )
-
- switch filter.HashVersion {
- case 2:
- h0, err = murmur3SeededV2(seed0, path)
- if err != nil {
- return key{}, err
- }
-
- h1, err = murmur3SeededV2(seed1, path)
- if err != nil {
- return key{}, err
- }
- case 1:
- h0, err = murmur3SeededV1(seed0, path)
- if err != nil {
- return key{}, err
- }
-
- h1, err = murmur3SeededV1(seed1, path)
- if err != nil {
- return key{}, err
- }
- default:
- return key{}, ErrInvalid
- }
-
- hashCount, err := intconv.Uint32ToInt(filter.NumHashes)
- if err != nil {
- return key{}, ErrInvalid
- }
-
- hashes := make([]uint32, hashCount)
- for i := range hashCount {
- iU32, err := intconv.IntToUint32(i)
- if err != nil {
- return key{}, ErrInvalid
- }
-
- hashes[i] = h0 + iU32*h1
- }
-
- return key{hashes: hashes}, nil
-}
-
-func filterContainsKey(filter *Filter, key key) bool {
- if len(filter.Data) == 0 {
- return false
- }
-
- mod := uint64(len(filter.Data)) * 8
- for _, h := range key.hashes {
- idx := uint64(h) % mod
- bytePos := idx / 8
-
- bit := byte(1 << (idx & 7))
- if filter.Data[bytePos]&bit == 0 {
- return false
- }
- }
-
- return true
-}
diff --git a/commitgraph/bloom/murmur.go b/commitgraph/bloom/murmur.go
deleted file mode 100644
index 363b63ae..00000000
--- a/commitgraph/bloom/murmur.go
+++ /dev/null
@@ -1,127 +0,0 @@
-package bloom
-
-import "codeberg.org/lindenii/furgit/internal/intconv"
-
-func murmur3SeededV2(seed uint32, data []byte) (uint32, error) {
- const (
- c1 = 0xcc9e2d51
- c2 = 0x1b873593
- r1 = 15
- r2 = 13
- m = 5
- n = 0xe6546b64
- )
-
- h := seed
-
- nblocks := len(data) / 4
- for i := range nblocks {
- k := uint32(data[4*i]) |
- (uint32(data[4*i+1]) << 8) |
- (uint32(data[4*i+2]) << 16) |
- (uint32(data[4*i+3]) << 24)
- k *= c1
- k = (k << r1) | (k >> (32 - r1))
- k *= c2
-
- h ^= k
- h = (h << r2) | (h >> (32 - r2))
- h = h*m + n
- }
-
- var k1 uint32
-
- tail := data[nblocks*4:]
- switch len(tail) & 3 {
- case 3:
- k1 ^= uint32(tail[2]) << 16
-
- fallthrough
- case 2:
- k1 ^= uint32(tail[1]) << 8
-
- fallthrough
- case 1:
- k1 ^= uint32(tail[0])
- k1 *= c1
- k1 = (k1 << r1) | (k1 >> (32 - r1))
- k1 *= c2
- h ^= k1
- }
-
- dataLen, err := intconv.IntToUint32(len(data))
- if err != nil {
- return 0, err
- }
-
- h ^= dataLen
- h ^= h >> 16
- h *= 0x85ebca6b
- h ^= h >> 13
- h *= 0xc2b2ae35
- h ^= h >> 16
-
- return h, nil
-}
-
-func murmur3SeededV1(seed uint32, data []byte) (uint32, error) {
- const (
- c1 = 0xcc9e2d51
- c2 = 0x1b873593
- r1 = 15
- r2 = 13
- m = 5
- n = 0xe6546b64
- )
-
- h := seed
-
- nblocks := len(data) / 4
- for i := range nblocks {
- k := intconv.SignExtendByteToUint32(data[4*i]) |
- (intconv.SignExtendByteToUint32(data[4*i+1]) << 8) |
- (intconv.SignExtendByteToUint32(data[4*i+2]) << 16) |
- (intconv.SignExtendByteToUint32(data[4*i+3]) << 24)
- k *= c1
- k = (k << r1) | (k >> (32 - r1))
- k *= c2
-
- h ^= k
- h = (h << r2) | (h >> (32 - r2))
- h = h*m + n
- }
-
- var k1 uint32
-
- tail := data[nblocks*4:]
- switch len(tail) & 3 {
- case 3:
- k1 ^= intconv.SignExtendByteToUint32(tail[2]) << 16
-
- fallthrough
- case 2:
- k1 ^= intconv.SignExtendByteToUint32(tail[1]) << 8
-
- fallthrough
- case 1:
- k1 ^= intconv.SignExtendByteToUint32(tail[0])
- k1 *= c1
- k1 = (k1 << r1) | (k1 >> (32 - r1))
- k1 *= c2
- h ^= k1
- }
-
- dataLen, err := intconv.IntToUint32(len(data))
- if err != nil {
- return 0, err
- }
-
- h ^= dataLen
- h ^= h >> 16
- h *= 0x85ebca6b
- h ^= h >> 13
- h *= 0xc2b2ae35
- h ^= h >> 16
-
- return h, nil
-}
diff --git a/commitgraph/bloom/settings.go b/commitgraph/bloom/settings.go
deleted file mode 100644
index 764653bd..00000000
--- a/commitgraph/bloom/settings.go
+++ /dev/null
@@ -1,50 +0,0 @@
-package bloom
-
-import (
- "encoding/binary"
-
- "codeberg.org/lindenii/furgit/internal/intconv"
-)
-
-// Settings describe the changed-paths Bloom filter parameters stored in
-// commit-graph BDAT chunks.
-//
-// Obviously, they must match the repository's commit-graph settings to
-// interpret filters correctly.
-type Settings struct {
- HashVersion uint32
- NumHashes uint32
- BitsPerEntry uint32
- MaxChangePaths uint32
-}
-
-// ParseSettings reads Bloom filter settings from a BDAT chunk header.
-func ParseSettings(bdat []byte) (*Settings, error) {
- if len(bdat) < DataHeaderSize {
- return nil, ErrInvalid
- }
-
- settings := &Settings{
- HashVersion: binary.BigEndian.Uint32(bdat[0:4]),
- NumHashes: binary.BigEndian.Uint32(bdat[4:8]),
- BitsPerEntry: binary.BigEndian.Uint32(bdat[8:12]),
- MaxChangePaths: DefaultMaxChange,
- }
-
- switch settings.HashVersion {
- case 1, 2:
- default:
- return nil, ErrInvalid
- }
-
- if settings.NumHashes == 0 {
- return nil, ErrInvalid
- }
-
- _, err := intconv.Uint32ToInt(settings.NumHashes)
- if err != nil {
- return nil, ErrInvalid
- }
-
- return settings, nil
-}