Delete everything, I'm redesigning this.

I'll stop using a flat package and make things much more modular.
And also experiment with streaming APIs so large blobs don't OOM us.

2 files changed, 0 insertions, 241 deletions

diff --git a/internal/bloom/bloom.go b/internal/bloom/bloom.go
deleted file mode 100644
index c1a116d6..00000000
--- a/internal/bloom/bloom.go
+++ /dev/null
@@ -1,236 +0,0 @@
-// Package bloom provides a bloom filter implementation used for changed-path
-// filters in Git commit graphs.
-package bloom
-
-import "encoding/binary"
-
-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
-)
-
-// 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
-}
-
-// 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
-	Version 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,
-	}
-	return settings, nil
-}
-
-// 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, settings *Settings) bool {
-	if f == nil || settings == nil {
-		return false
-	}
-	if len(f.Data) == 0 {
-		return false
-	}
-	keys := keyvec(path, settings)
-	for i := range keys {
-		if filterContainsKey(f, &keys[i], settings) {
-			return true
-		}
-	}
-	return false
-}
-
-type key struct {
-	hashes []uint32
-}
-
-func keyvec(path []byte, settings *Settings) []key {
-	if len(path) == 0 {
-		return nil
-	}
-	count := 1
-	for _, b := range path {
-		if b == '/' {
-			count++
-		}
-	}
-	keys := make([]key, 0, count)
-	keys = append(keys, keyFill(path, settings))
-	for i := len(path) - 1; i >= 0; i-- {
-		if path[i] == '/' {
-			keys = append(keys, keyFill(path[:i], settings))
-		}
-	}
-	return keys
-}
-
-func keyFill(path []byte, settings *Settings) key {
-	const seed0 = 0x293ae76f
-	const seed1 = 0x7e646e2c
-	var h0, h1 uint32
-	if settings.HashVersion == 2 {
-		h0 = murmur3SeededV2(seed0, path)
-		h1 = murmur3SeededV2(seed1, path)
-	} else {
-		h0 = murmur3SeededV1(seed0, path)
-		h1 = murmur3SeededV1(seed1, path)
-	}
-	hashes := make([]uint32, settings.NumHashes)
-	for i := uint32(0); i < settings.NumHashes; i++ {
-		hashes[i] = h0 + i*h1
-	}
-	return key{hashes: hashes}
-}
-
-func filterContainsKey(filter *Filter, key *key, settings *Settings) bool {
-	if filter == nil || key == nil || settings == nil {
-		return false
-	}
-	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
-}
-
-func murmur3SeededV2(seed uint32, data []byte) uint32 {
-	const (
-		c1 = 0xcc9e2d51
-		c2 = 0x1b873593
-		r1 = 15
-		r2 = 13
-		m  = 5
-		n  = 0xe6546b64
-	)
-	h := seed
-	nblocks := len(data) / 4
-	for i := 0; i < nblocks; i++ {
-		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
-	}
-
-	h ^= uint32(len(data))
-	h ^= h >> 16
-	h *= 0x85ebca6b
-	h ^= h >> 13
-	h *= 0xc2b2ae35
-	h ^= h >> 16
-	return h
-}
-
-func murmur3SeededV1(seed uint32, data []byte) uint32 {
-	const (
-		c1 = 0xcc9e2d51
-		c2 = 0x1b873593
-		r1 = 15
-		r2 = 13
-		m  = 5
-		n  = 0xe6546b64
-	)
-	h := seed
-	nblocks := len(data) / 4
-	for i := 0; i < nblocks; i++ {
-		b0 := int8(data[4*i])
-		b1 := int8(data[4*i+1])
-		b2 := int8(data[4*i+2])
-		b3 := int8(data[4*i+3])
-		k := uint32(b0) |
-			(uint32(b1) << 8) |
-			(uint32(b2) << 16) |
-			(uint32(b3) << 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(int8(tail[2])) << 16
-		fallthrough
-	case 2:
-		k1 ^= uint32(int8(tail[1])) << 8
-		fallthrough
-	case 1:
-		k1 ^= uint32(int8(tail[0]))
-		k1 *= c1
-		k1 = (k1 << r1) | (k1 >> (32 - r1))
-		k1 *= c2
-		h ^= k1
-	}
-
-	h ^= uint32(len(data))
-	h ^= h >> 16
-	h *= 0x85ebca6b
-	h ^= h >> 13
-	h *= 0xc2b2ae35
-	h ^= h >> 16
-	return h
-}
diff --git a/internal/bloom/errors.go b/internal/bloom/errors.go
deleted file mode 100644
index fe38d1bc..00000000
--- a/internal/bloom/errors.go
+++ /dev/null
@@ -1,5 +0,0 @@
-package bloom
-
-import "errors"
-
-var ErrInvalid = errors.New("bloom: invalid data")