switch to fork of go-git

vendor/github.com/jesseduffield/go-git/v5/plumbing/cache/buffer_lru.go

@@ -0,0 +1,98 @@
+package cache
+
+import (
+	"container/list"
+	"sync"
+)
+
+// BufferLRU implements an object cache with an LRU eviction policy and a
+// maximum size (measured in object size).
+type BufferLRU struct {
+	MaxSize FileSize
+
+	actualSize FileSize
+	ll         *list.List
+	cache      map[int64]*list.Element
+	mut        sync.Mutex
+}
+
+// NewBufferLRU creates a new BufferLRU with the given maximum size. The maximum
+// size will never be exceeded.
+func NewBufferLRU(maxSize FileSize) *BufferLRU {
+	return &BufferLRU{MaxSize: maxSize}
+}
+
+// NewBufferLRUDefault creates a new BufferLRU with the default cache size.
+func NewBufferLRUDefault() *BufferLRU {
+	return &BufferLRU{MaxSize: DefaultMaxSize}
+}
+
+type buffer struct {
+	Key   int64
+	Slice []byte
+}
+
+// Put puts a buffer into the cache. If the buffer is already in the cache, it
+// will be marked as used. Otherwise, it will be inserted. A buffers might
+// be evicted to make room for the new one.
+func (c *BufferLRU) Put(key int64, slice []byte) {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	if c.cache == nil {
+		c.actualSize = 0
+		c.cache = make(map[int64]*list.Element, 1000)
+		c.ll = list.New()
+	}
+
+	bufSize := FileSize(len(slice))
+	if ee, ok := c.cache[key]; ok {
+		oldBuf := ee.Value.(buffer)
+		// in this case bufSize is a delta: new size - old size
+		bufSize -= FileSize(len(oldBuf.Slice))
+		c.ll.MoveToFront(ee)
+		ee.Value = buffer{key, slice}
+	} else {
+		if bufSize > c.MaxSize {
+			return
+		}
+		ee := c.ll.PushFront(buffer{key, slice})
+		c.cache[key] = ee
+	}
+
+	c.actualSize += bufSize
+	for c.actualSize > c.MaxSize {
+		last := c.ll.Back()
+		lastObj := last.Value.(buffer)
+		lastSize := FileSize(len(lastObj.Slice))
+
+		c.ll.Remove(last)
+		delete(c.cache, lastObj.Key)
+		c.actualSize -= lastSize
+	}
+}
+
+// Get returns a buffer by its key. It marks the buffer as used. If the buffer
+// is not in the cache, (nil, false) will be returned.
+func (c *BufferLRU) Get(key int64) ([]byte, bool) {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	ee, ok := c.cache[key]
+	if !ok {
+		return nil, false
+	}
+
+	c.ll.MoveToFront(ee)
+	return ee.Value.(buffer).Slice, true
+}
+
+// Clear the content of this buffer cache.
+func (c *BufferLRU) Clear() {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	c.ll = nil
+	c.cache = nil
+	c.actualSize = 0
+}

vendor/github.com/jesseduffield/go-git/v5/plumbing/cache/common.go

@@ -0,0 +1,39 @@
+package cache
+
+import "github.com/jesseduffield/go-git/v5/plumbing"
+
+const (
+	Byte FileSize = 1 << (iota * 10)
+	KiByte
+	MiByte
+	GiByte
+)
+
+type FileSize int64
+
+const DefaultMaxSize FileSize = 96 * MiByte
+
+// Object is an interface to a object cache.
+type Object interface {
+	// Put puts the given object into the cache. Whether this object will
+	// actually be put into the cache or not is implementation specific.
+	Put(o plumbing.EncodedObject)
+	// Get gets an object from the cache given its hash. The second return value
+	// is true if the object was returned, and false otherwise.
+	Get(k plumbing.Hash) (plumbing.EncodedObject, bool)
+	// Clear clears every object from the cache.
+	Clear()
+}
+
+// Buffer is an interface to a buffer cache.
+type Buffer interface {
+	// Put puts a buffer into the cache. If the buffer is already in the cache,
+	// it will be marked as used. Otherwise, it will be inserted. Buffer might
+	// be evicted to make room for the new one.
+	Put(key int64, slice []byte)
+	// Get returns a buffer by its key. It marks the buffer as used. If the
+	// buffer is not in the cache, (nil, false) will be returned.
+	Get(key int64) ([]byte, bool)
+	// Clear clears every object from the cache.
+	Clear()
+}

vendor/github.com/jesseduffield/go-git/v5/plumbing/cache/object_lru.go

@@ -0,0 +1,101 @@
+package cache
+
+import (
+	"container/list"
+	"sync"
+
+	"github.com/jesseduffield/go-git/v5/plumbing"
+)
+
+// ObjectLRU implements an object cache with an LRU eviction policy and a
+// maximum size (measured in object size).
+type ObjectLRU struct {
+	MaxSize FileSize
+
+	actualSize FileSize
+	ll         *list.List
+	cache      map[interface{}]*list.Element
+	mut        sync.Mutex
+}
+
+// NewObjectLRU creates a new ObjectLRU with the given maximum size. The maximum
+// size will never be exceeded.
+func NewObjectLRU(maxSize FileSize) *ObjectLRU {
+	return &ObjectLRU{MaxSize: maxSize}
+}
+
+// NewObjectLRUDefault creates a new ObjectLRU with the default cache size.
+func NewObjectLRUDefault() *ObjectLRU {
+	return &ObjectLRU{MaxSize: DefaultMaxSize}
+}
+
+// Put puts an object into the cache. If the object is already in the cache, it
+// will be marked as used. Otherwise, it will be inserted. A single object might
+// be evicted to make room for the new object.
+func (c *ObjectLRU) Put(obj plumbing.EncodedObject) {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	if c.cache == nil {
+		c.actualSize = 0
+		c.cache = make(map[interface{}]*list.Element, 1000)
+		c.ll = list.New()
+	}
+
+	objSize := FileSize(obj.Size())
+	key := obj.Hash()
+	if ee, ok := c.cache[key]; ok {
+		oldObj := ee.Value.(plumbing.EncodedObject)
+		// in this case objSize is a delta: new size - old size
+		objSize -= FileSize(oldObj.Size())
+		c.ll.MoveToFront(ee)
+		ee.Value = obj
+	} else {
+		if objSize > c.MaxSize {
+			return
+		}
+		ee := c.ll.PushFront(obj)
+		c.cache[key] = ee
+	}
+
+	c.actualSize += objSize
+	for c.actualSize > c.MaxSize {
+		last := c.ll.Back()
+		if last == nil {
+			c.actualSize = 0
+			break
+		}
+
+		lastObj := last.Value.(plumbing.EncodedObject)
+		lastSize := FileSize(lastObj.Size())
+
+		c.ll.Remove(last)
+		delete(c.cache, lastObj.Hash())
+		c.actualSize -= lastSize
+	}
+}
+
+// Get returns an object by its hash. It marks the object as used. If the object
+// is not in the cache, (nil, false) will be returned.
+func (c *ObjectLRU) Get(k plumbing.Hash) (plumbing.EncodedObject, bool) {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	ee, ok := c.cache[k]
+	if !ok {
+		return nil, false
+	}
+
+	c.ll.MoveToFront(ee)
+	return ee.Value.(plumbing.EncodedObject), true
+}
+
+// Clear the content of this object cache.
+func (c *ObjectLRU) Clear() {
+	c.mut.Lock()
+	defer c.mut.Unlock()
+
+	c.ll = nil
+	c.cache = nil
+	c.actualSize = 0
+}