aboutsummaryrefslogtreecommitdiffstats
path: root/plumbing/format/idxfile
diff options
context:
space:
mode:
authorMáximo Cuadros <mcuadros@gmail.com>2019-04-27 00:20:19 +0200
committerGitHub <noreply@github.com>2019-04-27 00:20:19 +0200
commitf22c6b9dd07d6f4f2d578250c65b4572916488f9 (patch)
tree46eae69d79e0c99e56cf50efc686e1c61fbc7d60 /plumbing/format/idxfile
parentca5d7bb1a790303d2ca245cb6225850bcf5d12a6 (diff)
parent5943b4548d43cd5ed7975e29fa057a4b0cb180cf (diff)
downloadgo-git-f22c6b9dd07d6f4f2d578250c65b4572916488f9.tar.gz
Merge pull request #1136 from filipnavara/idxfile-nobuf
plumbing: format/idxfile, avoid creating temporary buffers to decode integers
Diffstat (limited to 'plumbing/format/idxfile')
-rw-r--r--plumbing/format/idxfile/idxfile.go79
1 files changed, 28 insertions, 51 deletions
diff --git a/plumbing/format/idxfile/idxfile.go b/plumbing/format/idxfile/idxfile.go
index 26cca59..14b5860 100644
--- a/plumbing/format/idxfile/idxfile.go
+++ b/plumbing/format/idxfile/idxfile.go
@@ -5,8 +5,9 @@ import (
"io"
"sort"
+ encbin "encoding/binary"
+
"gopkg.in/src-d/go-git.v4/plumbing"
- "gopkg.in/src-d/go-git.v4/utils/binary"
)
const (
@@ -122,41 +123,32 @@ func (idx *MemoryIndex) FindOffset(h plumbing.Hash) (int64, error) {
return 0, plumbing.ErrObjectNotFound
}
- offset, err := idx.getOffset(k, i)
+ offset := idx.getOffset(k, i)
if !idx.offsetHashIsFull {
// Save the offset for reverse lookup
if idx.offsetHash == nil {
idx.offsetHash = make(map[int64]plumbing.Hash)
}
- idx.offsetHash[offset] = h
+ idx.offsetHash[int64(offset)] = h
}
- return offset, err
+ return int64(offset), nil
}
const isO64Mask = uint64(1) << 31
-func (idx *MemoryIndex) getOffset(firstLevel, secondLevel int) (int64, error) {
+func (idx *MemoryIndex) getOffset(firstLevel, secondLevel int) uint64 {
offset := secondLevel << 2
- buf := bytes.NewBuffer(idx.Offset32[firstLevel][offset : offset+4])
- ofs, err := binary.ReadUint32(buf)
- if err != nil {
- return -1, err
- }
+ ofs := encbin.BigEndian.Uint32(idx.Offset32[firstLevel][offset : offset+4])
if (uint64(ofs) & isO64Mask) != 0 {
offset := 8 * (uint64(ofs) & ^isO64Mask)
- buf := bytes.NewBuffer(idx.Offset64[offset : offset+8])
- n, err := binary.ReadUint64(buf)
- if err != nil {
- return -1, err
- }
-
- return int64(n), nil
+ n := encbin.BigEndian.Uint64(idx.Offset64[offset : offset+8])
+ return n
}
- return int64(ofs), nil
+ return uint64(ofs)
}
// FindCRC32 implements the Index interface.
@@ -167,13 +159,12 @@ func (idx *MemoryIndex) FindCRC32(h plumbing.Hash) (uint32, error) {
return 0, plumbing.ErrObjectNotFound
}
- return idx.getCRC32(k, i)
+ return idx.getCRC32(k, i), nil
}
-func (idx *MemoryIndex) getCRC32(firstLevel, secondLevel int) (uint32, error) {
+func (idx *MemoryIndex) getCRC32(firstLevel, secondLevel int) uint32 {
offset := secondLevel << 2
- buf := bytes.NewBuffer(idx.CRC32[firstLevel][offset : offset+4])
- return binary.ReadUint32(buf)
+ return encbin.BigEndian.Uint32(idx.CRC32[firstLevel][offset : offset+4])
}
// FindHash implements the Index interface.
@@ -213,22 +204,19 @@ func (idx *MemoryIndex) genOffsetHash() error {
idx.offsetHash = make(map[int64]plumbing.Hash, count)
idx.offsetHashIsFull = true
- iter, err := idx.Entries()
- if err != nil {
- return err
- }
-
- for {
- entry, err := iter.Next()
- if err != nil {
- if err == io.EOF {
- return nil
- }
- return err
+ var hash plumbing.Hash
+ i := uint32(0)
+ for firstLevel, fanoutValue := range idx.Fanout {
+ mappedFirstLevel := idx.FanoutMapping[firstLevel]
+ for secondLevel := uint32(0); i < fanoutValue; i++ {
+ copy(hash[:], idx.Names[mappedFirstLevel][secondLevel*objectIDLength:])
+ offset := int64(idx.getOffset(mappedFirstLevel, int(secondLevel)))
+ idx.offsetHash[offset] = hash
+ secondLevel++
}
-
- idx.offsetHash[int64(entry.Offset)] = entry.Hash
}
+
+ return nil
}
// Count implements the Index interface.
@@ -297,22 +285,11 @@ func (i *idxfileEntryIter) Next() (*Entry, error) {
continue
}
+ mappedFirstLevel := i.idx.FanoutMapping[i.firstLevel]
entry := new(Entry)
- ofs := i.secondLevel * objectIDLength
- copy(entry.Hash[:], i.idx.Names[i.idx.FanoutMapping[i.firstLevel]][ofs:])
-
- pos := i.idx.FanoutMapping[entry.Hash[0]]
-
- offset, err := i.idx.getOffset(pos, i.secondLevel)
- if err != nil {
- return nil, err
- }
- entry.Offset = uint64(offset)
-
- entry.CRC32, err = i.idx.getCRC32(pos, i.secondLevel)
- if err != nil {
- return nil, err
- }
+ copy(entry.Hash[:], i.idx.Names[mappedFirstLevel][i.secondLevel*objectIDLength:])
+ entry.Offset = i.idx.getOffset(mappedFirstLevel, i.secondLevel)
+ entry.CRC32 = i.idx.getCRC32(mappedFirstLevel, i.secondLevel)
i.secondLevel++
i.total++