From ff33e649bd6fec535e6b9bf43a55242f9d210e8a Mon Sep 17 00:00:00 2001
From: Urban Wallasch <urban.wallasch@freenet.de>
Date: Sat, 6 Apr 2019 20:36:19 +0200
Subject: [PATCH] * Added -I directory index file command line option; default:
 index.goph. * Dropped -M message command line option. * Refactored send file
 and send index logic.

---
 config.go    | 17 +++++++-----
 gogopherd.go | 73 +++++++++++++++++++++++++++++++++++++---------------
 2 files changed, 62 insertions(+), 28 deletions(-)

diff --git a/config.go b/config.go
index 8b0564d..2928658 100644
--- a/config.go
+++ b/config.go
@@ -12,6 +12,8 @@ import (
 	"flag"
 	"fmt"
 	"os"
+	"path/filepath"
+	"strings"
 )
 
 var cfg = struct {
@@ -19,7 +21,7 @@ var cfg = struct {
 	port    string
 	fqdn    string
 	docRoot string
-	message string
+	dirIdx  string
 	fsymln  bool
 	showdot bool
 	noidx   bool
@@ -29,7 +31,7 @@ var cfg = struct {
 	port:    "7070",
 	fqdn:    "localhost",
 	docRoot: ".",
-	message: "",
+	dirIdx:  "index.goph",
 	fsymln:  false,
 	showdot: false,
 	noidx:   false,
@@ -42,7 +44,7 @@ func initialize() {
 	flag.StringVar(&cfg.port, "p", cfg.port, "TCP port to listen on")
 	flag.StringVar(&cfg.fqdn, "f", cfg.fqdn, "fully qualified domain name")
 	flag.StringVar(&cfg.docRoot, "r", cfg.docRoot, "document root directory")
-	flag.StringVar(&cfg.message, "M", cfg.message, "index greeter message")
+	flag.StringVar(&cfg.dirIdx, "I", cfg.dirIdx, "directory index page")
 	flag.BoolVar(&help, "h", help, "show this help page")
 	flag.BoolVar(&cfg.fsymln, "s", cfg.fsymln, "follow symbolic links")
 	flag.BoolVar(&cfg.showdot, "d", cfg.showdot, "allow access to dotfiles")
@@ -67,19 +69,20 @@ func initialize() {
 	cfg.docRoot, err = canonicalizePath(cfg.docRoot)
 	checkFatal(err, "canonicalizePath "+cfg.docRoot)
 
-	if cfg.message != "" {
-		cfg.message = fmt.Sprintf("i%s\t\t\t\r\n", cfg.message)
+	cfg.dirIdx = filepath.Base(strings.TrimSpace(cfg.dirIdx))
+	if cfg.dirIdx == "." || cfg.dirIdx == pathSep {
+		cfg.dirIdx = ""
 	}
 
 	tracer.Print("Version ", version)
+	tracer.Print("fqdn:      ", cfg.fqdn)
 	tracer.Print("interface: ", cfg.iface)
 	tracer.Print("TCP port:  ", cfg.port)
 	tracer.Print("doc root:  ", cfg.docRoot)
+	tracer.Print("dir index: ", cfg.dirIdx)
 	tracer.Print("fsymlinks: ", cfg.fsymln)
 	tracer.Print("showdot:   ", cfg.showdot)
 	tracer.Print("noidx:     ", cfg.noidx)
-	tracer.Print("fqdn:      ", cfg.fqdn)
-	tracer.Print("message:   ", cfg.message)
 	tracer.Print("verbose:   ", cfg.verbose)
 }
 
diff --git a/gogopherd.go b/gogopherd.go
index 1e6bfe7..bc31d17 100644
--- a/gogopherd.go
+++ b/gogopherd.go
@@ -24,8 +24,7 @@ import (
 	"strings"
 )
 
-func createIndex(selector string) (string, error) {
-	dirname := cfg.docRoot + selector
+func createIndex(dirname string, selector string) (string, error) {
 	fi, err := ioutil.ReadDir(dirname)
 	if check(err, "Readdir "+dirname) != nil {
 		return "", err
@@ -84,6 +83,35 @@ func createIndex(selector string) (string, error) {
 	return list, error(nil)
 }
 
+func sendIndex(conn net.Conn, path string, selector string) (int64, error) {
+	var nbytes int
+	nbytes = 0
+	diridx, err := createIndex(path, selector)
+	if err == nil {
+		if selector == "" {
+			selector = pathSep
+		}
+		page := ""
+		// TODO append banner
+		page += "iIndex of " + selector + "\tErr\t" + cfg.fqdn + "\t" + cfg.port + "\r\n"
+		page += diridx
+		// TODO append footer
+		nbytes, err = conn.Write([]byte(page))
+	}
+	return int64(nbytes), err
+}
+
+func sendFile(conn net.Conn, path string) (int64, error) {
+	var nbytes int64
+	nbytes = 0
+	file, err := os.Open(path)
+	if err == nil {
+		defer file.Close()
+		nbytes, err = io.Copy(conn, file)
+	}
+	return nbytes, err
+}
+
 func replyErr(conn net.Conn, msg string) {
 	tracer.Print("sending error reply: " + msg)
 	s := "3Gopher Meditation: " + msg + "\tErr\t" + cfg.fqdn + "\t" + cfg.port + "\r\n"
@@ -140,31 +168,34 @@ func handleRequest(conn net.Conn) {
 	tracer.Print("selector: '", selector, "'")
 	var nbytes int64
 	if fmode.IsDir() {
-		if cfg.noidx {
-			replyErr(conn, "403")
-			return
-		}
-		diridx, err := createIndex(selector)
-		if check(err, "makeIndex "+path) != nil {
-			replyErr(conn, "404")
-			return
+		err = nil
+		if cfg.dirIdx != "" {
+			// send directory index file
+			idxpath := path + pathSep + cfg.dirIdx
+			nbytes, err = sendFile(conn, idxpath)
+			if err != nil {
+				tracer.Print("no index file in " + path)
+			}
 		}
-		nb, err := conn.Write([]byte(cfg.message + diridx))
-		if check(err, "Write") != nil {
-			return
+		if err != nil {
+			// failed to send directory index file
+			if cfg.noidx {
+				replyErr(conn, "403")
+				return
+			}
+			// generate and send directory listing
+			nbytes, err = sendIndex(conn, path, selector)
+			if check(err, "sendIndex ") != nil {
+				replyErr(conn, "403")
+				return
+			}
 		}
-		nbytes = int64(nb)
 	} else if fmode.IsRegular() {
-		file, err := os.Open(path)
-		if check(err, "Open "+path) != nil {
+		nbytes, err = sendFile(conn, path)
+		if check(err, "sendFile "+path) != nil {
 			replyErr(conn, "404")
 			return
 		}
-		defer file.Close()
-		nbytes, err = io.Copy(conn, file)
-		if check(err, "Copy "+path) != nil {
-			return
-		}
 	} else {
 		replyErr(conn, "404")
 		return
-- 
2.30.2