deps: Added golang-lru

Godeps/Godeps.json

 {
 	"ImportPath": "github.com/ethereum/go-ethereum",
-	"GoVersion": "go1.4.2",
+	"GoVersion": "go1.4",
 	"Packages": [
 		"./..."
 	],
@@ -28,6 +28,11 @@
 			"ImportPath": "github.com/gizak/termui",
 			"Rev": "bab8dce01c193d82bc04888a0a9a7814d505f532"
 		},
+		{
+			"ImportPath": "github.com/howeyc/fsnotify",
+			"Comment": "v0.9.0-11-g6b1ef89",
+			"Rev": "6b1ef893dc11e0447abda6da20a5203481878dda"
+		},
 		{
 			"ImportPath": "github.com/huin/goupnp",
 			"Rev": "5cff77a69fb22f5f1774c4451ea2aab63d4d2f20"

Godeps/_workspace/src/github.com/hashicorp/golang-lru/.gitignore

+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
+*.test

Godeps/_workspace/src/github.com/hashicorp/golang-lru/README.md

+golang-lru
+==========
+
+This provides the `lru` package which implements a fixed-size
+thread safe LRU cache. It is based on the cache in Groupcache.
+
+Documentation
+=============
+
+Full docs are available on [Godoc](http://godoc.org/github.com/hashicorp/golang-lru)
+
+Example
+=======
+
+Using the LRU is very simple:
+
+```go
+l, _ := New(128)
+for i := 0; i < 256; i++ {
+    l.Add(i, nil)
+}
+if l.Len() != 128 {
+    panic(fmt.Sprintf("bad len: %v", l.Len()))
+}
+```

Godeps/_workspace/src/github.com/hashicorp/golang-lru/lru.go

+// This package provides a simple LRU cache. It is based on the
+// LRU implementation in groupcache:
+// https://github.com/golang/groupcache/tree/master/lru
+package lru
+
+import (
+	"container/list"
+	"errors"
+	"sync"
+)
+
+// Cache is a thread-safe fixed size LRU cache.
+type Cache struct {
+	size      int
+	evictList *list.List
+	items     map[interface{}]*list.Element
+	lock      sync.RWMutex
+	onEvicted func(key interface{}, value interface{})
+}
+
+// entry is used to hold a value in the evictList
+type entry struct {
+	key   interface{}
+	value interface{}
+}
+
+// New creates an LRU of the given size
+func New(size int) (*Cache, error) {
+	return NewWithEvict(size, nil)
+}
+
+func NewWithEvict(size int, onEvicted func(key interface{}, value interface{})) (*Cache, error) {
+	if size <= 0 {
+		return nil, errors.New("Must provide a positive size")
+	}
+	c := &Cache{
+		size:      size,
+		evictList: list.New(),
+		items:     make(map[interface{}]*list.Element, size),
+		onEvicted: onEvicted,
+	}
+	return c, nil
+}
+
+// Purge is used to completely clear the cache
+func (c *Cache) Purge() {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
+	if c.onEvicted != nil {
+		for k, v := range c.items {
+			c.onEvicted(k, v.Value.(*entry).value)
+		}
+	}
+
+	c.evictList = list.New()
+	c.items = make(map[interface{}]*list.Element, c.size)
+}
+
+// Add adds a value to the cache.  Returns true if an eviction occured.
+func (c *Cache) Add(key, value interface{}) bool {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
+	// Check for existing item
+	if ent, ok := c.items[key]; ok {
+		c.evictList.MoveToFront(ent)
+		ent.Value.(*entry).value = value
+		return false
+	}
+
+	// Add new item
+	ent := &entry{key, value}
+	entry := c.evictList.PushFront(ent)
+	c.items[key] = entry
+
+	evict := c.evictList.Len() > c.size
+	// Verify size not exceeded
+	if evict {
+		c.removeOldest()
+	}
+	return evict
+}
+
+// Get looks up a key's value from the cache.
+func (c *Cache) Get(key interface{}) (value interface{}, ok bool) {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
+	if ent, ok := c.items[key]; ok {
+		c.evictList.MoveToFront(ent)
+		return ent.Value.(*entry).value, true
+	}
+	return
+}
+
+// Check if a key is in the cache, without updating the recent-ness or deleting it for being stale.
+func (c *Cache) Contains(key interface{}) (ok bool) {
+	c.lock.RLock()
+	defer c.lock.RUnlock()
+
+	_, ok = c.items[key]
+	return ok
+}
+
+// Returns the key value (or undefined if not found) without updating the "recently used"-ness of the key.
+// (If you find yourself using this a lot, you might be using the wrong sort of data structure, but there are some use cases where it's handy.)
+func (c *Cache) Peek(key interface{}) (value interface{}, ok bool) {
+	c.lock.RLock()
+	defer c.lock.RUnlock()
+
+	if ent, ok := c.items[key]; ok {
+		return ent.Value.(*entry).value, true
+	}
+	return nil, ok
+}
+
+// Remove removes the provided key from the cache.
+func (c *Cache) Remove(key interface{}) {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+
+	if ent, ok := c.items[key]; ok {
+		c.removeElement(ent)
+	}
+}
+
+// RemoveOldest removes the oldest item from the cache.
+func (c *Cache) RemoveOldest() {
+	c.lock.Lock()
+	defer c.lock.Unlock()
+	c.removeOldest()
+}
+
+// Keys returns a slice of the keys in the cache, from oldest to newest.
+func (c *Cache) Keys() []interface{} {
+	c.lock.RLock()
+	defer c.lock.RUnlock()
+
+	keys := make([]interface{}, len(c.items))
+	ent := c.evictList.Back()
+	i := 0
+	for ent != nil {
+		keys[i] = ent.Value.(*entry).key
+		ent = ent.Prev()
+		i++
+	}
+
+	return keys
+}
+
+// Len returns the number of items in the cache.
+func (c *Cache) Len() int {
+	c.lock.RLock()
+	defer c.lock.RUnlock()
+	return c.evictList.Len()
+}
+
+// removeOldest removes the oldest item from the cache.
+func (c *Cache) removeOldest() {
+	ent := c.evictList.Back()
+	if ent != nil {
+		c.removeElement(ent)
+	}
+}
+
+// removeElement is used to remove a given list element from the cache
+func (c *Cache) removeElement(e *list.Element) {
+	c.evictList.Remove(e)
+	kv := e.Value.(*entry)
+	delete(c.items, kv.key)
+	if c.onEvicted != nil {
+		c.onEvicted(kv.key, kv.value)
+	}
+}

Godeps/_workspace/src/github.com/hashicorp/golang-lru/lru_test.go

+package lru
+
+import "testing"
+
+func TestLRU(t *testing.T) {
+	evictCounter := 0
+	onEvicted := func(k interface{}, v interface{}) {
+		if k != v {
+			t.Fatalf("Evict values not equal (%v!=%v)", k, v)
+		}
+		evictCounter += 1
+	}
+	l, err := NewWithEvict(128, onEvicted)
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	for i := 0; i < 256; i++ {
+		l.Add(i, i)
+	}
+	if l.Len() != 128 {
+		t.Fatalf("bad len: %v", l.Len())
+	}
+
+	if evictCounter != 128 {
+		t.Fatalf("bad evict count: %v", evictCounter)
+	}
+
+	for i, k := range l.Keys() {
+		if v, ok := l.Get(k); !ok || v != k || v != i+128 {
+			t.Fatalf("bad key: %v", k)
+		}
+	}
+	for i := 0; i < 128; i++ {
+		_, ok := l.Get(i)
+		if ok {
+			t.Fatalf("should be evicted")
+		}
+	}
+	for i := 128; i < 256; i++ {
+		_, ok := l.Get(i)
+		if !ok {
+			t.Fatalf("should not be evicted")
+		}
+	}
+	for i := 128; i < 192; i++ {
+		l.Remove(i)
+		_, ok := l.Get(i)
+		if ok {
+			t.Fatalf("should be deleted")
+		}
+	}
+
+	l.Get(192) // expect 192 to be last key in l.Keys()
+
+	for i, k := range l.Keys() {
+		if (i < 63 && k != i+193) || (i == 63 && k != 192) {
+			t.Fatalf("out of order key: %v", k)
+		}
+	}
+
+	l.Purge()
+	if l.Len() != 0 {
+		t.Fatalf("bad len: %v", l.Len())
+	}
+	if _, ok := l.Get(200); ok {
+		t.Fatalf("should contain nothing")
+	}
+}
+
+// test that Add returns true/false if an eviction occured
+func TestLRUAdd(t *testing.T) {
+	evictCounter := 0
+	onEvicted := func(k interface{}, v interface{}) {
+		evictCounter += 1
+	}
+
+	l, err := NewWithEvict(1, onEvicted)
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	if l.Add(1, 1) == true || evictCounter != 0 {
+		t.Errorf("should not have an eviction")
+	}
+	if l.Add(2, 2) == false || evictCounter != 1 {
+		t.Errorf("should have an eviction")
+	}
+}
+
+// test that Contains doesn't update recent-ness
+func TestLRUContains(t *testing.T) {
+	l, err := New(2)
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	l.Add(1, 1)
+	l.Add(2, 2)
+	if !l.Contains(1) {
+		t.Errorf("1 should be contained")
+	}
+
+	l.Add(3, 3)
+	if l.Contains(1) {
+		t.Errorf("Contains should not have updated recent-ness of 1")
+	}
+}
+
+// test that Peek doesn't update recent-ness
+func TestLRUPeek(t *testing.T) {
+	l, err := New(2)
+	if err != nil {
+		t.Fatalf("err: %v", err)
+	}
+
+	l.Add(1, 1)
+	l.Add(2, 2)
+	if v, ok := l.Peek(1); !ok || v != 1 {
+		t.Errorf("1 should be set to 1: %v, %v", v, ok)
+	}
+
+	l.Add(3, 3)
+	if l.Contains(1) {
+		t.Errorf("should not have updated recent-ness of 1")
+	}
+}