Files
zeekay b61441f7d7 Volume: node-local persistent volumes, under our own name
A fork of Rancher's local-path-provisioner at v0.0.36. The behaviour is
unchanged and deliberately so — a directory on the node a pod lands on is
the right thing for a disk. What changes is identity.

The provisioner answers to hanzo.ai/volume rather than rancher.io/local-path.
That is not branding: two provisioners sharing one name race for the same
claims, and a stock k3s carries the upstream one, so a cluster running both
would settle our storage by chance. Data lives at /var/lib/hanzo/volume, so
reading a Hanzo cluster does not mean learning another vendor's directory.

Apache-2.0 as published, unaltered, with Rancher's attribution in NOTICE.

The README says what this is not: durability. A volume here dies with its
node. That is hanzoai/replicate's question, one layer up, and keeping the
two apart is what lets the disk stay this simple.
2026-09-07 17:30:01 -07:00

73 lines
1.9 KiB
Go

/*
Copyright 2017 The Kubernetes Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package buffer
// RingGrowing is a growing ring buffer.
// Not thread safe.
type RingGrowing struct {
data []interface{}
n int // Size of Data
beg int // First available element
readable int // Number of data items available
}
// NewRingGrowing constructs a new RingGrowing instance with provided parameters.
func NewRingGrowing(initialSize int) *RingGrowing {
return &RingGrowing{
data: make([]interface{}, initialSize),
n: initialSize,
}
}
// ReadOne reads (consumes) first item from the buffer if it is available, otherwise returns false.
func (r *RingGrowing) ReadOne() (data interface{}, ok bool) {
if r.readable == 0 {
return nil, false
}
r.readable--
element := r.data[r.beg]
r.data[r.beg] = nil // Remove reference to the object to help GC
if r.beg == r.n-1 {
// Was the last element
r.beg = 0
} else {
r.beg++
}
return element, true
}
// WriteOne adds an item to the end of the buffer, growing it if it is full.
func (r *RingGrowing) WriteOne(data interface{}) {
if r.readable == r.n {
// Time to grow
newN := r.n * 2
newData := make([]interface{}, newN)
to := r.beg + r.readable
if to <= r.n {
copy(newData, r.data[r.beg:to])
} else {
copied := copy(newData, r.data[r.beg:])
copy(newData[copied:], r.data[:(to%r.n)])
}
r.beg = 0
r.data = newData
r.n = newN
}
r.data[(r.readable+r.beg)%r.n] = data
r.readable++
}