add diskFilesWorldReadable option to control 0644/0600 choice for new files

Server.go

@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"log"
 	"net/http"
+	"os"
 	"regexp"
 	"strings"
 	"time"
@@ -23,12 +24,21 @@ type ServerPublicProperties struct {
 type ServerOptions struct {
 	DataDirectory          string
 	DBPath                 string
+	DiskFilesWorldReadable bool
 	BandwidthLimit         int64
 	TrustXForwardedFor     bool
 	EnableHomepage         bool
 	ServerPublicProperties
 }
 
+func (this *ServerOptions) FileMode() os.FileMode {
+	if this.DiskFilesWorldReadable {
+		return 0644
+	} else {
+		return 0600
+	}
+}
+
 type Server struct {
 	opts           ServerOptions
 	db             *bolt.DB

cmd/contented/main.go

@@ -20,6 +20,7 @@ func main() {
 	maxUploadSpeed := flag.Int("speed", 0, "Maximum upload speed in bytes/sec (set zero for unlimited)")
 	trustXForwardedFor := flag.Bool("trustXForwardedFor", false, "Trust X-Forwarded-For reverse proxy headers")
 	enableHomepage := flag.Bool("enableHomepage", true, "Enable homepage (disable for embedded use only)")
+	diskFilesWorldReadable := flag.Bool("diskFilesWorldReadable", false, "Save files as 0644 instead of 0600")
 
 	flag.Parse()
 
@@ -29,6 +30,7 @@ func main() {
 		BandwidthLimit:         int64(*maxUploadSpeed),
 		TrustXForwardedFor:     *trustXForwardedFor,
 		EnableHomepage:         *enableHomepage,
+		DiskFilesWorldReadable: *diskFilesWorldReadable,
 		ServerPublicProperties: contented.ServerPublicProperties{
 			AppTitle:       *appTitle,
 			MaxUploadBytes: int64(*maxUploadMb) * 1024 * 1024,

upload.go

@@ -91,7 +91,7 @@ func (this *Server) handleUploadFile(src multipart.File, hdr *multipart.FileHead
 
 	// Save file to disk
 	fileHash := hex.EncodeToString(hasher.Sum(nil))
-	dest, err := os.OpenFile(filepath.Join(this.opts.DataDirectory, fileHash), os.O_CREATE|os.O_WRONLY, 0600)
+	dest, err := os.OpenFile(filepath.Join(this.opts.DataDirectory, fileHash), os.O_CREATE|os.O_WRONLY, this.opts.FileMode())
 	shouldSave := true
 	if err != nil && os.IsExist(err) {
 		// hash matches existing upload