contrib: remove "persistent-https" remote helper

The "persistent-https" remote helper supposedly speeds up SSL operations
by running a daemon that keeps a connection open to a remote server. It
is effectively unmaintained nowadays: the last time it received an
update was in accb613afd2 (contrib/persistent-https: use Git version for
build label, 2016-07-20) and its parent commits to make it compile with
Go 1.7+.

This Go toolchain is somewhat dated by now though and unsupported. The
oldest still-supported toolchain is Go 1.23, which was released in
August 2024. It is not possible to compile the remote helper with that
Go version anymore:

    $ go version
    go version go1.23.8 linux/amd64
    $ make
    case $(go version) in \
    "go version go"1.[0-5].*) EQ=" " ;; *) EQ="=" ;; esac && \
    go build -o git-remote-persistent-https \
            -ldflags "-X main._BUILD_EMBED_LABEL${EQ}GIT_VERSION=2.49.0.943.g965a70ebf62"
    go: cannot find main module, but found .git/config in /home/pks/Development/git
            to create a module there, run:
            cd ../.. && go mod init
    make: *** [Makefile:31: git-remote-persistent-https] Error 1

The problem is that modern Go toolchains require a "go.mod" file, but we
don't have any such files. This requirement exists since quite a while
already, so it's clear that nobody has tried to use this remote helper
anytime recent.

Remove the remote helper.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 0 insertions, 190 deletions

diff --git a/contrib/persistent-https/proxy.go b/contrib/persistent-https/proxy.go
deleted file mode 100644
index bb0cdba386..0000000000
--- a/contrib/persistent-https/proxy.go
+++ /dev/null
@@ -1,190 +0,0 @@
-// Copyright 2012 Google Inc. All Rights Reserved.
-//
-// 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 main
-
-import (
-	"fmt"
-	"log"
-	"net"
-	"net/http"
-	"net/http/httputil"
-	"os"
-	"os/exec"
-	"os/signal"
-	"sync"
-	"syscall"
-	"time"
-)
-
-type Proxy struct {
-	BuildLabel         string
-	MaxIdleDuration    time.Duration
-	PollUpdateInterval time.Duration
-
-	ul        net.Listener
-	httpAddr  string
-	httpsAddr string
-}
-
-func (p *Proxy) Run() error {
-	hl, err := net.Listen("tcp", "127.0.0.1:0")
-	if err != nil {
-		return fmt.Errorf("http listen failed: %v", err)
-	}
-	defer hl.Close()
-
-	hsl, err := net.Listen("tcp", "127.0.0.1:0")
-	if err != nil {
-		return fmt.Errorf("https listen failed: %v", err)
-	}
-	defer hsl.Close()
-
-	p.ul, err = DefaultSocket.Listen()
-	if err != nil {
-		c, derr := DefaultSocket.Dial()
-		if derr == nil {
-			c.Close()
-			fmt.Println("OK\nA proxy is already running... exiting")
-			return nil
-		} else if e, ok := derr.(*net.OpError); ok && e.Err == syscall.ECONNREFUSED {
-			// Nothing is listening on the socket, unlink it and try again.
-			syscall.Unlink(DefaultSocket.Path())
-			p.ul, err = DefaultSocket.Listen()
-		}
-		if err != nil {
-			return fmt.Errorf("unix listen failed on %v: %v", DefaultSocket.Path(), err)
-		}
-	}
-	defer p.ul.Close()
-	go p.closeOnSignal()
-	go p.closeOnUpdate()
-
-	p.httpAddr = hl.Addr().String()
-	p.httpsAddr = hsl.Addr().String()
-	fmt.Printf("OK\nListening on unix socket=%v http=%v https=%v\n",
-		p.ul.Addr(), p.httpAddr, p.httpsAddr)
-
-	result := make(chan error, 2)
-	go p.serveUnix(result)
-	go func() {
-		result <- http.Serve(hl, &httputil.ReverseProxy{
-			FlushInterval: 500 * time.Millisecond,
-			Director:      func(r *http.Request) {},
-		})
-	}()
-	go func() {
-		result <- http.Serve(hsl, &httputil.ReverseProxy{
-			FlushInterval: 500 * time.Millisecond,
-			Director: func(r *http.Request) {
-				r.URL.Scheme = "https"
-			},
-		})
-	}()
-	return <-result
-}
-
-type socketContext struct {
-	sync.WaitGroup
-	mutex sync.Mutex
-	last  time.Time
-}
-
-func (sc *socketContext) Done() {
-	sc.mutex.Lock()
-	defer sc.mutex.Unlock()
-	sc.last = time.Now()
-	sc.WaitGroup.Done()
-}
-
-func (p *Proxy) serveUnix(result chan<- error) {
-	sockCtx := &socketContext{}
-	go p.closeOnIdle(sockCtx)
-
-	var err error
-	for {
-		var uconn net.Conn
-		uconn, err = p.ul.Accept()
-		if err != nil {
-			err = fmt.Errorf("accept failed: %v", err)
-			break
-		}
-		sockCtx.Add(1)
-		go p.handleUnixConn(sockCtx, uconn)
-	}
-	sockCtx.Wait()
-	result <- err
-}
-
-func (p *Proxy) handleUnixConn(sockCtx *socketContext, uconn net.Conn) {
-	defer sockCtx.Done()
-	defer uconn.Close()
-	data := []byte(fmt.Sprintf("%v\n%v", p.httpsAddr, p.httpAddr))
-	uconn.SetDeadline(time.Now().Add(5 * time.Second))
-	for i := 0; i < 2; i++ {
-		if n, err := uconn.Write(data); err != nil {
-			log.Printf("error sending http addresses: %+v\n", err)
-			return
-		} else if n != len(data) {
-			log.Printf("sent %d data bytes, wanted %d\n", n, len(data))
-			return
-		}
-		if _, err := uconn.Read([]byte{0, 0, 0, 0}); err != nil {
-			log.Printf("error waiting for Ack: %+v\n", err)
-			return
-		}
-	}
-	// Wait without a deadline for the client to finish via EOF
-	uconn.SetDeadline(time.Time{})
-	uconn.Read([]byte{0, 0, 0, 0})
-}
-
-func (p *Proxy) closeOnIdle(sockCtx *socketContext) {
-	for d := p.MaxIdleDuration; d > 0; {
-		time.Sleep(d)
-		sockCtx.Wait()
-		sockCtx.mutex.Lock()
-		if d = sockCtx.last.Add(p.MaxIdleDuration).Sub(time.Now()); d <= 0 {
-			log.Println("graceful shutdown from idle timeout")
-			p.ul.Close()
-		}
-		sockCtx.mutex.Unlock()
-	}
-}
-
-func (p *Proxy) closeOnUpdate() {
-	for {
-		time.Sleep(p.PollUpdateInterval)
-		if out, err := exec.Command(os.Args[0], "--print_label").Output(); err != nil {
-			log.Printf("error polling for updated binary: %v\n", err)
-		} else if s := string(out[:len(out)-1]); p.BuildLabel != s {
-			log.Printf("graceful shutdown from updated binary: %q --> %q\n", p.BuildLabel, s)
-			p.ul.Close()
-			break
-		}
-	}
-}
-
-func (p *Proxy) closeOnSignal() {
-	ch := make(chan os.Signal, 10)
-	signal.Notify(ch, os.Interrupt, os.Kill, os.Signal(syscall.SIGTERM), os.Signal(syscall.SIGHUP))
-	sig := <-ch
-	p.ul.Close()
-	switch sig {
-	case os.Signal(syscall.SIGHUP):
-		log.Printf("graceful shutdown from signal: %v\n", sig)
-	default:
-		log.Fatalf("exiting from signal: %v\n", sig)
-	}
-}