tools/install.sh

   1 #!/bin/sh
   2 #
   3 # This is an actually-safe install command which installs the new
   4 # file atomically in the new location, rather than overwriting
   5 # existing files.
   6 #
   7
   8 usage() {
   9 printf "usage: %s [-D] [-l] [-m mode] src dest\n" "$0" 1>&2
  10 exit 1
  11 }
  12
  13 mkdirp=
  14 symlink=
  15 mode=755
  16
  17 while getopts Dlm: name ; do
  18 case "$name" in
  19 D) mkdirp=yes ;;
  20 l) symlink=yes ;;
  21 m) mode=$OPTARG ;;
  22 ?) usage ;;
  23 esac
  24 done
  25 shift $(($OPTIND - 1))
  26
  27 test "$#" -eq 2 || usage
  28 src=$1
  29 dst=$2
  30 tmp="$dst.tmp.$$"
  31
  32 case "$dst" in
  33 */) printf "%s: %s ends in /\n", "$0" "$dst" 1>&2 ; exit 1 ;;
  34 esac
  35
  36 set -C
  37 set -e
  38
  39 if test "$mkdirp" ; then
  40 umask 022
  41 case "$2" in
  42 */*) mkdir -p "${dst%/*}" ;;
  43 esac
  44 fi
  45
  46 trap 'rm -f "$tmp"' EXIT INT QUIT TERM HUP
  47
  48 umask 077
  49
  50 if test "$symlink" ; then
  51 ln -s "$1" "$tmp"
  52 else
  53 cat < "$1" > "$tmp"
  54 chmod "$mode" "$tmp"
  55 fi
  56
  57 mv -f "$tmp" "$2"
  58 test -d "$2" && {
  59 rm -f "$2/$tmp"
  60 printf "%s: %s is a directory\n" "$0" "$dst" 1>&2
  61 exit 1
  62 }
  63
  64 exit 0