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

70 lines
1.6 KiB
Go

// Copyright 2018 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.
// Package detrand provides deterministically random functionality.
//
// The pseudo-randomness of these functions is seeded by the program binary
// itself and guarantees that the output does not change within a program,
// while ensuring that the output is unstable across different builds.
package detrand
import (
"encoding/binary"
"hash/fnv"
"os"
)
// Disable disables detrand such that all functions returns the zero value.
// This function is not concurrent-safe and must be called during program init.
func Disable() {
randSeed = 0
}
// Bool returns a deterministically random boolean.
func Bool() bool {
return randSeed%2 == 1
}
// Intn returns a deterministically random integer between 0 and n-1, inclusive.
func Intn(n int) int {
if n <= 0 {
panic("must be positive")
}
return int(randSeed % uint64(n))
}
// randSeed is a best-effort at an approximate hash of the Go binary.
var randSeed = binaryHash()
func binaryHash() uint64 {
// Open the Go binary.
s, err := os.Executable()
if err != nil {
return 0
}
f, err := os.Open(s)
if err != nil {
return 0
}
defer f.Close()
// Hash the size and several samples of the Go binary.
const numSamples = 8
var buf [64]byte
h := fnv.New64()
fi, err := f.Stat()
if err != nil {
return 0
}
binary.LittleEndian.PutUint64(buf[:8], uint64(fi.Size()))
h.Write(buf[:8])
for i := int64(0); i < numSamples; i++ {
if _, err := f.ReadAt(buf[:], i*fi.Size()/numSamples); err != nil {
return 0
}
h.Write(buf[:])
}
return h.Sum64()
}