pkg/osutil: add arguments to RestartProcess

use it to restart server with -reindex

Fixes #753

Change-Id: Iff4a8c725820f8204d9539b9bafe5f4d3b65780c

pkg/osutil/restart_unix.go

@@ -56,13 +56,25 @@ func SelfPath() (string, error) {
 	return "", errors.New("SelfPath not implemented for " + runtime.GOOS)
 }
 
-// RestartProcess returns an error if things couldn't be
-// restarted.  On success, this function never returns
-// because the process becomes the new process.
-func RestartProcess() error {
+// RestartProcess restarts the process with the given arguments, if any,
+// replacing the original process's arguments. It defaults to os.Args otherwise. It
+// returns an error if things couldn't be restarted. On success, this function
+// never returns because the process becomes the new process.
+func RestartProcess(arg ...string) error {
 	path, err := SelfPath()
 	if err != nil {
 		return fmt.Errorf("RestartProcess failed: %v", err)
 	}
-	return syscall.Exec(path, os.Args, os.Environ())
+
+	var args []string
+	if len(arg) > 0 {
+		args = append(args, os.Args[0])
+		for _, v := range arg {
+			args = append(args, v)
+		}
+	} else {
+		args = os.Args
+	}
+
+	return syscall.Exec(path, args, os.Environ())
 }

pkg/server/status.go

@@ -243,7 +243,8 @@ func (sh *StatusHandler) serveStatusHTML(rw http.ResponseWriter, req *http.Reque
 	f("</ul>")
 
 	f("<h2>Admin</h2>")
-	f("<form method='post' action='restart' onsubmit='return confirm(\"Really restart now?\")'><button>restart server</button></form>")
+	f("<form method='post' action='restart' onsubmit='return confirm(\"Really restart now?\")'><button>restart server</button>")
+	f("<input type='checkbox' name='reindex'> reindex<br></form>")
 
 	f("<h2>Handlers</h2>")
 	f("<p>As JSON: <a href='status.json'>status.json</a>; and the <a href='%s?camli.mode=config'>discovery JSON</a>.</p>", st.rootPrefix)
@@ -285,13 +286,15 @@ func (sh *StatusHandler) serveRestart(rw http.ResponseWriter, req *http.Request)
 		}
 	}
 
+	reindex := (req.FormValue("reindex") == "on")
+
 	log.Println("Restarting camlistored")
 	rw.Header().Set("Connection", "close")
 	http.Redirect(rw, req, sh.prefix, http.StatusFound)
 	if f, ok := rw.(http.Flusher); ok {
 		f.Flush()
 	}
-	osutil.RestartProcess()
+	osutil.RestartProcess(fmt.Sprintf("-reindex=%t", reindex))
 }
 
 var cgoEnabled bool