| // 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. |
| |
| package vcweb |
| |
| import ( |
| "log" |
| "net/http" |
| "net/http/cgi" |
| "os/exec" |
| "runtime" |
| "slices" |
| "sync" |
| ) |
| |
| type gitHandler struct { |
| once sync.Once |
| gitPath string |
| gitPathErr error |
| } |
| |
| func (h *gitHandler) Available() bool { |
| if runtime.GOOS == "plan9" { |
| // The Git command is usually not the real Git on Plan 9. |
| // See https://golang.org/issues/29640. |
| return false |
| } |
| h.once.Do(func() { |
| h.gitPath, h.gitPathErr = exec.LookPath("git") |
| }) |
| return h.gitPathErr == nil |
| } |
| |
| func (h *gitHandler) Handler(dir string, env []string, logger *log.Logger) (http.Handler, error) { |
| if !h.Available() { |
| return nil, ServerNotInstalledError{name: "git"} |
| } |
| |
| baseEnv := append(slices.Clip(env), |
| "GIT_PROJECT_ROOT="+dir, |
| "GIT_HTTP_EXPORT_ALL=1", |
| ) |
| |
| handler := http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) { |
| // The Git client sends the requested Git protocol version as a |
| // "Git-Protocol" HTTP request header, which the CGI host then converts |
| // to an environment variable (HTTP_GIT_PROTOCOL). |
| // |
| // However, versions of Git older that 2.34.0 don't recognize the |
| // HTTP_GIT_PROTOCOL variable, and instead need that value to be set in the |
| // GIT_PROTOCOL variable. We do so here so that vcweb can work reliably |
| // with older Git releases. (As of the time of writing, the Go project's |
| // builders were on Git version 2.30.2.) |
| env := slices.Clip(baseEnv) |
| if p := req.Header.Get("Git-Protocol"); p != "" { |
| env = append(env, "GIT_PROTOCOL="+p) |
| } |
| |
| h := &cgi.Handler{ |
| Path: h.gitPath, |
| Logger: logger, |
| Args: []string{"http-backend"}, |
| Dir: dir, |
| Env: env, |
| } |
| h.ServeHTTP(w, req) |
| }) |
| |
| return handler, nil |
| } |