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authorLibravatar tobi <31960611+tsmethurst@users.noreply.github.com>2022-06-11 11:09:31 +0200
committerLibravatar GitHub <noreply@github.com>2022-06-11 11:09:31 +0200
commitcf5c6d724d381a867a7ff5d82fb9432e26c395e8 (patch)
tree859bb6fa4a3de2fdcb218b24bb33ab7219e80ce7 /vendor/golang.org/x/net/internal/socket/mmsghdr_unix.go
parent[chore] Webfinger rework (#627) (diff)
downloadgotosocial-cf5c6d724d381a867a7ff5d82fb9432e26c395e8.tar.xz
[chore] Validate/set account domain (#619)
* add miekg/dns dependency * set/validate accountDomain
Diffstat (limited to 'vendor/golang.org/x/net/internal/socket/mmsghdr_unix.go')
-rw-r--r--vendor/golang.org/x/net/internal/socket/mmsghdr_unix.go180
1 files changed, 180 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/internal/socket/mmsghdr_unix.go b/vendor/golang.org/x/net/internal/socket/mmsghdr_unix.go
new file mode 100644
index 000000000..0bfcf7afc
--- /dev/null
+++ b/vendor/golang.org/x/net/internal/socket/mmsghdr_unix.go
@@ -0,0 +1,180 @@
+// Copyright 2017 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.
+
+//go:build aix || linux || netbsd
+// +build aix linux netbsd
+
+package socket
+
+import (
+ "net"
+ "os"
+ "sync"
+ "syscall"
+)
+
+type mmsghdrs []mmsghdr
+
+func (hs mmsghdrs) unpack(ms []Message, parseFn func([]byte, string) (net.Addr, error), hint string) error {
+ for i := range hs {
+ ms[i].N = int(hs[i].Len)
+ ms[i].NN = hs[i].Hdr.controllen()
+ ms[i].Flags = hs[i].Hdr.flags()
+ if parseFn != nil {
+ var err error
+ ms[i].Addr, err = parseFn(hs[i].Hdr.name(), hint)
+ if err != nil {
+ return err
+ }
+ }
+ }
+ return nil
+}
+
+// mmsghdrsPacker packs Message-slices into mmsghdrs (re-)using pre-allocated buffers.
+type mmsghdrsPacker struct {
+ // hs are the pre-allocated mmsghdrs.
+ hs mmsghdrs
+ // sockaddrs is the pre-allocated buffer for the Hdr.Name buffers.
+ // We use one large buffer for all messages and slice it up.
+ sockaddrs []byte
+ // vs are the pre-allocated iovecs.
+ // We allocate one large buffer for all messages and slice it up. This allows to reuse the buffer
+ // if the number of buffers per message is distributed differently between calls.
+ vs []iovec
+}
+
+func (p *mmsghdrsPacker) prepare(ms []Message) {
+ n := len(ms)
+ if n <= cap(p.hs) {
+ p.hs = p.hs[:n]
+ } else {
+ p.hs = make(mmsghdrs, n)
+ }
+ if n*sizeofSockaddrInet6 <= cap(p.sockaddrs) {
+ p.sockaddrs = p.sockaddrs[:n*sizeofSockaddrInet6]
+ } else {
+ p.sockaddrs = make([]byte, n*sizeofSockaddrInet6)
+ }
+
+ nb := 0
+ for _, m := range ms {
+ nb += len(m.Buffers)
+ }
+ if nb <= cap(p.vs) {
+ p.vs = p.vs[:nb]
+ } else {
+ p.vs = make([]iovec, nb)
+ }
+}
+
+func (p *mmsghdrsPacker) pack(ms []Message, parseFn func([]byte, string) (net.Addr, error), marshalFn func(net.Addr, []byte) int) mmsghdrs {
+ p.prepare(ms)
+ hs := p.hs
+ vsRest := p.vs
+ saRest := p.sockaddrs
+ for i := range hs {
+ nvs := len(ms[i].Buffers)
+ vs := vsRest[:nvs]
+ vsRest = vsRest[nvs:]
+
+ var sa []byte
+ if parseFn != nil {
+ sa = saRest[:sizeofSockaddrInet6]
+ saRest = saRest[sizeofSockaddrInet6:]
+ } else if marshalFn != nil {
+ n := marshalFn(ms[i].Addr, saRest)
+ if n > 0 {
+ sa = saRest[:n]
+ saRest = saRest[n:]
+ }
+ }
+ hs[i].Hdr.pack(vs, ms[i].Buffers, ms[i].OOB, sa)
+ }
+ return hs
+}
+
+// syscaller is a helper to invoke recvmmsg and sendmmsg via the RawConn.Read/Write interface.
+// It is reusable, to amortize the overhead of allocating a closure for the function passed to
+// RawConn.Read/Write.
+type syscaller struct {
+ n int
+ operr error
+ hs mmsghdrs
+ flags int
+
+ boundRecvmmsgF func(uintptr) bool
+ boundSendmmsgF func(uintptr) bool
+}
+
+func (r *syscaller) init() {
+ r.boundRecvmmsgF = r.recvmmsgF
+ r.boundSendmmsgF = r.sendmmsgF
+}
+
+func (r *syscaller) recvmmsg(c syscall.RawConn, hs mmsghdrs, flags int) (int, error) {
+ r.n = 0
+ r.operr = nil
+ r.hs = hs
+ r.flags = flags
+ if err := c.Read(r.boundRecvmmsgF); err != nil {
+ return r.n, err
+ }
+ if r.operr != nil {
+ return r.n, os.NewSyscallError("recvmmsg", r.operr)
+ }
+ return r.n, nil
+}
+
+func (r *syscaller) recvmmsgF(s uintptr) bool {
+ r.n, r.operr = recvmmsg(s, r.hs, r.flags)
+ return ioComplete(r.flags, r.operr)
+}
+
+func (r *syscaller) sendmmsg(c syscall.RawConn, hs mmsghdrs, flags int) (int, error) {
+ r.n = 0
+ r.operr = nil
+ r.hs = hs
+ r.flags = flags
+ if err := c.Write(r.boundSendmmsgF); err != nil {
+ return r.n, err
+ }
+ if r.operr != nil {
+ return r.n, os.NewSyscallError("sendmmsg", r.operr)
+ }
+ return r.n, nil
+}
+
+func (r *syscaller) sendmmsgF(s uintptr) bool {
+ r.n, r.operr = sendmmsg(s, r.hs, r.flags)
+ return ioComplete(r.flags, r.operr)
+}
+
+// mmsgTmps holds reusable temporary helpers for recvmmsg and sendmmsg.
+type mmsgTmps struct {
+ packer mmsghdrsPacker
+ syscaller syscaller
+}
+
+var defaultMmsgTmpsPool = mmsgTmpsPool{
+ p: sync.Pool{
+ New: func() interface{} {
+ tmps := new(mmsgTmps)
+ tmps.syscaller.init()
+ return tmps
+ },
+ },
+}
+
+type mmsgTmpsPool struct {
+ p sync.Pool
+}
+
+func (p *mmsgTmpsPool) Get() *mmsgTmps {
+ return p.p.Get().(*mmsgTmps)
+}
+
+func (p *mmsgTmpsPool) Put(tmps *mmsgTmps) {
+ p.p.Put(tmps)
+}