1 files changed, 51 insertions, 0 deletions
diff --git a/src/cmd/go/internal/vcweb/git.go b/src/cmd/go/internal/vcweb/git.go
new file mode 100644
index 0000000..5f9864e
--- /dev/null
+++ b/src/cmd/go/internal/vcweb/git.go
@@ -0,0 +1,51 @@
+// 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"
+	"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"}
+	}
+
+	handler := &cgi.Handler{
+		Path:   h.gitPath,
+		Logger: logger,
+		Args:   []string{"http-backend"},
+		Dir:    dir,
+		Env: append(env[:len(env):len(env)],
+			"GIT_PROJECT_ROOT="+dir,
+			"GIT_HTTP_EXPORT_ALL=1",
+		),
+	}
+
+	return handler, nil
+}