server_unix.go

// +build darwin dragonfly freebsd !android,linux netbsd openbsd solaris aix
// +build cgo

package sftp

import (
	"fmt"
	"os"
	"syscall"
	"time"
)

// ls -l style output for a file, which is in the 'long output' section of a readdir response packet
// this is a very simple (lazy) implementation, just enough to look almost like openssh in a few basic cases
func runLs(dirname string, dirent os.FileInfo) string {
	// example from openssh sftp server:
	// crw-rw-rw-    1 root     wheel           0 Jul 31 20:52 ttyvd
	// format:
	// {directory / char device / etc}{rwxrwxrwx}  {number of links} owner group size month day [time (this year) | year (otherwise)] name

	typeword := runLsTypeWord(dirent)

	var numLinks uint64 = 1
	if dirent.IsDir() {
		numLinks = 0
	}

	var uid, gid uint32

	if statt, ok := dirent.Sys().(*syscall.Stat_t); ok {
		// The type of Nlink varies form int16 (aix-ppc64) to uint64 (linux-amd64),
		// we cast up to uint64 to make all OS/ARCH combos source compatible.
		numLinks = uint64(statt.Nlink)
		uid = statt.Uid
		gid = statt.Gid
	}

	username := fmt.Sprintf("%d", uid)
	groupname := fmt.Sprintf("%d", gid)
	// TODO FIXME: uid -> username, gid -> groupname lookup for ls -l format output

	mtime := dirent.ModTime()
	monthStr := mtime.Month().String()[0:3]
	day := mtime.Day()
	year := mtime.Year()
	now := time.Now()
	isOld := mtime.Before(now.Add(-time.Hour * 24 * 365 / 2))

	yearOrTime := fmt.Sprintf("%02d:%02d", mtime.Hour(), mtime.Minute())
	if isOld {
		yearOrTime = fmt.Sprintf("%d", year)
	}

	return fmt.Sprintf("%s %4d %-8s %-8s %8d %s %2d %5s %s", typeword, numLinks, username, groupname, dirent.Size(), monthStr, day, yearOrTime, dirent.Name())
}