Method book

nocopy_linkbuffer.go:702–714

book will grow and malloc buffer to hold data. bookSize: The size of data that can be read at once. maxSize: The maximum size of data between two Release(). In some cases, this can guarantee all data allocated in one node to reduce copy.

(bookSize, maxSize int)

//
//	guarantee all data allocated in one node to reduce copy.
func (b *UnsafeLinkBuffer) book(bookSize, maxSize int) (p []byte) {
	l := cap(b.write.buf) - b.write.malloc
	// grow linkBuffer
	if l == 0 {
		l = maxSize
		b.write.next = newLinkBufferNode(maxSize)
		b.write = b.write.next
	}
	if l > bookSize {
		l = bookSize
	}
	return b.write.Malloc(l)
}

// bookAck will ack the first n malloc bytes and discard the rest.
//