plumbing: idxfile, Crc32 to CRC32 and return ok from findHashIndex

Signed-off-by: Miguel Molina <miguel@erizocosmi.co>

Author: erizocosmico

plumbing/format/idxfile/decoder.go

@@ -124,7 +124,7 @@ func readObjectNames(idx *MemoryIndex, r io.Reader) error {
 
 		idx.Names = append(idx.Names, bin)
 		idx.Offset32 = append(idx.Offset32, make([]byte, buckets*4))
-		idx.Crc32 = append(idx.Crc32, make([]byte, buckets*4))
+		idx.CRC32 = append(idx.CRC32, make([]byte, buckets*4))
 	}
 
 	return nil
@@ -133,7 +133,7 @@ func readObjectNames(idx *MemoryIndex, r io.Reader) error {
 func readCRC32(idx *MemoryIndex, r io.Reader) error {
 	for k := 0; k < fanout; k++ {
 		if pos := idx.FanoutMapping[k]; pos != noMapping {
-			if _, err := io.ReadFull(r, idx.Crc32[pos]); err != nil {
+			if _, err := io.ReadFull(r, idx.CRC32[pos]); err != nil {
 				return err
 			}
 		}

plumbing/format/idxfile/encoder.go

@@ -89,7 +89,7 @@ func (e *Encoder) encodeCRC32(idx *MemoryIndex) (int, error) {
 			continue
 		}
 
-		n, err := e.Write(idx.Crc32[pos])
+		n, err := e.Write(idx.CRC32[pos])
 		if err != nil {
 			return size, err
 		}

plumbing/format/idxfile/idxfile.go

@@ -41,12 +41,12 @@ type MemoryIndex struct {
 	Version uint32
 	Fanout  [256]uint32
 	// FanoutMapping maps the position in the fanout table to the position
-	// in the Names, Offset32 and Crc32 slices. This improves the memory
+	// in the Names, Offset32 and CRC32 slices. This improves the memory
 	// usage by not needing an array with unnecessary empty slots.
 	FanoutMapping    [256]int
 	Names            [][]byte
 	Offset32         [][]byte
-	Crc32            [][]byte
+	CRC32            [][]byte
 	Offset64         []byte
 	PackfileChecksum [20]byte
 	IdxChecksum      [20]byte
@@ -61,20 +61,20 @@ func NewMemoryIndex() *MemoryIndex {
 	return &MemoryIndex{}
 }
 
-func (idx *MemoryIndex) findHashIndex(h plumbing.Hash) int {
+func (idx *MemoryIndex) findHashIndex(h plumbing.Hash) (int, bool) {
 	k := idx.FanoutMapping[h[0]]
 	if k == noMapping {
-		return -1
+		return 0, false
 	}
 
 	if len(idx.Names) <= k {
-		return -1
+		return 0, false
 	}
 
 	data := idx.Names[k]
 	high := uint64(len(idx.Offset32[k])) >> 2
 	if high == 0 {
-		return -1
+		return 0, false
 	}
 
 	low := uint64(0)
@@ -86,7 +86,7 @@ func (idx *MemoryIndex) findHashIndex(h plumbing.Hash) int {
 		if cmp < 0 {
 			high = mid
 		} else if cmp == 0 {
-			return int(mid)
+			return int(mid), true
 		} else {
 			low = mid + 1
 		}
@@ -96,13 +96,13 @@ func (idx *MemoryIndex) findHashIndex(h plumbing.Hash) int {
 		}
 	}
 
-	return -1
+	return 0, false
 }
 
 // Contains implements the Index interface.
 func (idx *MemoryIndex) Contains(h plumbing.Hash) (bool, error) {
-	i := idx.findHashIndex(h)
-	return i >= 0, nil
+	_, ok := idx.findHashIndex(h)
+	return ok, nil
 }
 
 // FindOffset implements the Index interface.
@@ -112,8 +112,8 @@ func (idx *MemoryIndex) FindOffset(h plumbing.Hash) (int64, error) {
 	}
 
 	k := idx.FanoutMapping[h[0]]
-	i := idx.findHashIndex(h)
-	if i < 0 {
+	i, ok := idx.findHashIndex(h)
+	if !ok {
 		return 0, plumbing.ErrObjectNotFound
 	}
 
@@ -147,17 +147,17 @@ func (idx *MemoryIndex) getOffset(firstLevel, secondLevel int) (int64, error) {
 // FindCRC32 implements the Index interface.
 func (idx *MemoryIndex) FindCRC32(h plumbing.Hash) (uint32, error) {
 	k := idx.FanoutMapping[h[0]]
-	i := idx.findHashIndex(h)
-	if i < 0 {
+	i, ok := idx.findHashIndex(h)
+	if !ok {
 		return 0, plumbing.ErrObjectNotFound
 	}
 
-	return idx.getCrc32(k, i)
+	return idx.getCRC32(k, i)
 }
 
-func (idx *MemoryIndex) getCrc32(firstLevel, secondLevel int) (uint32, error) {
+func (idx *MemoryIndex) getCRC32(firstLevel, secondLevel int) (uint32, error) {
 	offset := secondLevel << 2
-	buf := bytes.NewBuffer(idx.Crc32[firstLevel][offset : offset+4])
+	buf := bytes.NewBuffer(idx.CRC32[firstLevel][offset : offset+4])
 	return binary.ReadUint32(buf)
 }
 
@@ -253,7 +253,7 @@ func (i *idxfileEntryIter) Next() (*Entry, error) {
 		}
 		entry.Offset = uint64(offset)
 
-		entry.CRC32, err = i.idx.getCrc32(pos, i.secondLevel)
+		entry.CRC32, err = i.idx.getCRC32(pos, i.secondLevel)
 		if err != nil {
 			return nil, err
 		}

plumbing/format/idxfile/writer.go

@@ -132,7 +132,7 @@ func (w *Writer) createIndex() (*MemoryIndex, error) {
 
 			idx.Names = append(idx.Names, make([]byte, 0))
 			idx.Offset32 = append(idx.Offset32, make([]byte, 0))
-			idx.Crc32 = append(idx.Crc32, make([]byte, 0))
+			idx.CRC32 = append(idx.CRC32, make([]byte, 0))
 		}
 
 		idx.Names[bucket] = append(idx.Names[bucket], o.Hash[:]...)
@@ -148,7 +148,7 @@ func (w *Writer) createIndex() (*MemoryIndex, error) {
 
 		buf.Truncate(0)
 		binary.WriteUint32(buf, uint32(o.CRC32))
-		idx.Crc32[bucket] = append(idx.Crc32[bucket], buf.Bytes()...)
+		idx.CRC32[bucket] = append(idx.CRC32[bucket], buf.Bytes()...)
 	}
 
 	for j := last + 1; j < 256; j++ {