implement a buffer for received StreamFrames

fixes #116, ref #115

utils/byteinterval_linkedlist.go

@@ -0,0 +1,214 @@
+// Generated by: main
+// TypeWriter: linkedlist
+// Directive: +gen on ByteInterval
+
+package utils
+
+// List is a modification of http://golang.org/pkg/container/list/
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// ByteIntervalElement is an element of a linked list.
+type ByteIntervalElement struct {
+	// Next and previous pointers in the doubly-linked list of elements.
+	// To simplify the implementation, internally a list l is implemented
+	// as a ring, such that &l.root is both the next element of the last
+	// list element (l.Back()) and the previous element of the first list
+	// element (l.Front()).
+	next, prev *ByteIntervalElement
+
+	// The list to which this element belongs.
+	list *ByteIntervalList
+
+	// The value stored with this element.
+	Value ByteInterval
+}
+
+// Next returns the next list element or nil.
+func (e *ByteIntervalElement) Next() *ByteIntervalElement {
+	if p := e.next; e.list != nil && p != &e.list.root {
+		return p
+	}
+	return nil
+}
+
+// Prev returns the previous list element or nil.
+func (e *ByteIntervalElement) Prev() *ByteIntervalElement {
+	if p := e.prev; e.list != nil && p != &e.list.root {
+		return p
+	}
+	return nil
+}
+
+// ByteIntervalList represents a doubly linked list.
+// The zero value for ByteIntervalList is an empty list ready to use.
+type ByteIntervalList struct {
+	root ByteIntervalElement // sentinel list element, only &root, root.prev, and root.next are used
+	len  int                 // current list length excluding (this) sentinel element
+}
+
+// Init initializes or clears list l.
+func (l *ByteIntervalList) Init() *ByteIntervalList {
+	l.root.next = &l.root
+	l.root.prev = &l.root
+	l.len = 0
+	return l
+}
+
+// New returns an initialized list.
+func NewByteIntervalList() *ByteIntervalList { return new(ByteIntervalList).Init() }
+
+// Len returns the number of elements of list l.
+// The complexity is O(1).
+func (l *ByteIntervalList) Len() int { return l.len }
+
+// Front returns the first element of list l or nil.
+func (l *ByteIntervalList) Front() *ByteIntervalElement {
+	if l.len == 0 {
+		return nil
+	}
+	return l.root.next
+}
+
+// Back returns the last element of list l or nil.
+func (l *ByteIntervalList) Back() *ByteIntervalElement {
+	if l.len == 0 {
+		return nil
+	}
+	return l.root.prev
+}
+
+// lazyInit lazily initializes a zero ByteIntervalList value.
+func (l *ByteIntervalList) lazyInit() {
+	if l.root.next == nil {
+		l.Init()
+	}
+}
+
+// insert inserts e after at, increments l.len, and returns e.
+func (l *ByteIntervalList) insert(e, at *ByteIntervalElement) *ByteIntervalElement {
+	n := at.next
+	at.next = e
+	e.prev = at
+	e.next = n
+	n.prev = e
+	e.list = l
+	l.len++
+	return e
+}
+
+// insertValue is a convenience wrapper for insert(&ByteIntervalElement{Value: v}, at).
+func (l *ByteIntervalList) insertValue(v ByteInterval, at *ByteIntervalElement) *ByteIntervalElement {
+	return l.insert(&ByteIntervalElement{Value: v}, at)
+}
+
+// remove removes e from its list, decrements l.len, and returns e.
+func (l *ByteIntervalList) remove(e *ByteIntervalElement) *ByteIntervalElement {
+	e.prev.next = e.next
+	e.next.prev = e.prev
+	e.next = nil // avoid memory leaks
+	e.prev = nil // avoid memory leaks
+	e.list = nil
+	l.len--
+	return e
+}
+
+// Remove removes e from l if e is an element of list l.
+// It returns the element value e.Value.
+func (l *ByteIntervalList) Remove(e *ByteIntervalElement) ByteInterval {
+	if e.list == l {
+		// if e.list == l, l must have been initialized when e was inserted
+		// in l or l == nil (e is a zero ByteIntervalElement) and l.remove will crash
+		l.remove(e)
+	}
+	return e.Value
+}
+
+// PushFront inserts a new element e with value v at the front of list l and returns e.
+func (l *ByteIntervalList) PushFront(v ByteInterval) *ByteIntervalElement {
+	l.lazyInit()
+	return l.insertValue(v, &l.root)
+}
+
+// PushBack inserts a new element e with value v at the back of list l and returns e.
+func (l *ByteIntervalList) PushBack(v ByteInterval) *ByteIntervalElement {
+	l.lazyInit()
+	return l.insertValue(v, l.root.prev)
+}
+
+// InsertBefore inserts a new element e with value v immediately before mark and returns e.
+// If mark is not an element of l, the list is not modified.
+func (l *ByteIntervalList) InsertBefore(v ByteInterval, mark *ByteIntervalElement) *ByteIntervalElement {
+	if mark.list != l {
+		return nil
+	}
+	// see comment in ByteIntervalList.Remove about initialization of l
+	return l.insertValue(v, mark.prev)
+}
+
+// InsertAfter inserts a new element e with value v immediately after mark and returns e.
+// If mark is not an element of l, the list is not modified.
+func (l *ByteIntervalList) InsertAfter(v ByteInterval, mark *ByteIntervalElement) *ByteIntervalElement {
+	if mark.list != l {
+		return nil
+	}
+	// see comment in ByteIntervalList.Remove about initialization of l
+	return l.insertValue(v, mark)
+}
+
+// MoveToFront moves element e to the front of list l.
+// If e is not an element of l, the list is not modified.
+func (l *ByteIntervalList) MoveToFront(e *ByteIntervalElement) {
+	if e.list != l || l.root.next == e {
+		return
+	}
+	// see comment in ByteIntervalList.Remove about initialization of l
+	l.insert(l.remove(e), &l.root)
+}
+
+// MoveToBack moves element e to the back of list l.
+// If e is not an element of l, the list is not modified.
+func (l *ByteIntervalList) MoveToBack(e *ByteIntervalElement) {
+	if e.list != l || l.root.prev == e {
+		return
+	}
+	// see comment in ByteIntervalList.Remove about initialization of l
+	l.insert(l.remove(e), l.root.prev)
+}
+
+// MoveBefore moves element e to its new position before mark.
+// If e or mark is not an element of l, or e == mark, the list is not modified.
+func (l *ByteIntervalList) MoveBefore(e, mark *ByteIntervalElement) {
+	if e.list != l || e == mark || mark.list != l {
+		return
+	}
+	l.insert(l.remove(e), mark.prev)
+}
+
+// MoveAfter moves element e to its new position after mark.
+// If e is not an element of l, or e == mark, the list is not modified.
+func (l *ByteIntervalList) MoveAfter(e, mark *ByteIntervalElement) {
+	if e.list != l || e == mark || mark.list != l {
+		return
+	}
+	l.insert(l.remove(e), mark)
+}
+
+// PushBackList inserts a copy of an other list at the back of list l.
+// The lists l and other may be the same.
+func (l *ByteIntervalList) PushBackList(other *ByteIntervalList) {
+	l.lazyInit()
+	for i, e := other.Len(), other.Front(); i > 0; i, e = i-1, e.Next() {
+		l.insertValue(e.Value, l.root.prev)
+	}
+}
+
+// PushFrontList inserts a copy of an other list at the front of list l.
+// The lists l and other may be the same.
+func (l *ByteIntervalList) PushFrontList(other *ByteIntervalList) {
+	l.lazyInit()
+	for i, e := other.Len(), other.Back(); i > 0; i, e = i-1, e.Prev() {
+		l.insertValue(e.Value, &l.root)
+	}
+}