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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 12:36:04 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 12:36:04 +0000
commitb09c6d56832eb1718c07d74abf3bc6ae3fe4e030 (patch)
treed2caec2610d4ea887803ec9e9c3cd77136c448ba /dependencies/pkg/mod/github.com/dgryski
parentInitial commit. (diff)
downloadicingadb-b09c6d56832eb1718c07d74abf3bc6ae3fe4e030.tar.xz
icingadb-b09c6d56832eb1718c07d74abf3bc6ae3fe4e030.zip
Adding upstream version 1.1.0.upstream/1.1.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/LICENSE21
-rw-r--r--dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/rdv.go79
-rw-r--r--dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/rdv_test.go18
3 files changed, 118 insertions, 0 deletions
diff --git a/dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/LICENSE b/dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/LICENSE
new file mode 100644
index 0000000..22080f7
--- /dev/null
+++ b/dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/LICENSE
@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2017-2020 Damian Gryski <damian@gryski.com>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/rdv.go b/dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/rdv.go
new file mode 100644
index 0000000..7a6f820
--- /dev/null
+++ b/dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/rdv.go
@@ -0,0 +1,79 @@
+package rendezvous
+
+type Rendezvous struct {
+ nodes map[string]int
+ nstr []string
+ nhash []uint64
+ hash Hasher
+}
+
+type Hasher func(s string) uint64
+
+func New(nodes []string, hash Hasher) *Rendezvous {
+ r := &Rendezvous{
+ nodes: make(map[string]int, len(nodes)),
+ nstr: make([]string, len(nodes)),
+ nhash: make([]uint64, len(nodes)),
+ hash: hash,
+ }
+
+ for i, n := range nodes {
+ r.nodes[n] = i
+ r.nstr[i] = n
+ r.nhash[i] = hash(n)
+ }
+
+ return r
+}
+
+func (r *Rendezvous) Lookup(k string) string {
+ // short-circuit if we're empty
+ if len(r.nodes) == 0 {
+ return ""
+ }
+
+ khash := r.hash(k)
+
+ var midx int
+ var mhash = xorshiftMult64(khash ^ r.nhash[0])
+
+ for i, nhash := range r.nhash[1:] {
+ if h := xorshiftMult64(khash ^ nhash); h > mhash {
+ midx = i + 1
+ mhash = h
+ }
+ }
+
+ return r.nstr[midx]
+}
+
+func (r *Rendezvous) Add(node string) {
+ r.nodes[node] = len(r.nstr)
+ r.nstr = append(r.nstr, node)
+ r.nhash = append(r.nhash, r.hash(node))
+}
+
+func (r *Rendezvous) Remove(node string) {
+ // find index of node to remove
+ nidx := r.nodes[node]
+
+ // remove from the slices
+ l := len(r.nstr)
+ r.nstr[nidx] = r.nstr[l]
+ r.nstr = r.nstr[:l]
+
+ r.nhash[nidx] = r.nhash[l]
+ r.nhash = r.nhash[:l]
+
+ // update the map
+ delete(r.nodes, node)
+ moved := r.nstr[nidx]
+ r.nodes[moved] = nidx
+}
+
+func xorshiftMult64(x uint64) uint64 {
+ x ^= x >> 12 // a
+ x ^= x << 25 // b
+ x ^= x >> 27 // c
+ return x * 2685821657736338717
+}
diff --git a/dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/rdv_test.go b/dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/rdv_test.go
new file mode 100644
index 0000000..f9c5583
--- /dev/null
+++ b/dependencies/pkg/mod/github.com/dgryski/go-rendezvous@v0.0.0-20200823014737-9f7001d12a5f/rdv_test.go
@@ -0,0 +1,18 @@
+package rendezvous
+
+import (
+ "hash/fnv"
+ "testing"
+)
+
+func hashString(s string) uint64 {
+ h := fnv.New64a()
+ h.Write([]byte(s))
+ return h.Sum64()
+}
+
+func TestEmpty(t *testing.T) {
+ r := New([]string{}, hashString)
+ r.Lookup("hello")
+
+}