rpush-continue

   1 #!/bin/bash
   2
   3 # Usage:
   4 #   rpush-continue SRC [--android|--unix] DEST ssh SSH_args..
   5 # or
   6 #   rpush-continue SRC [--android|--unix] DEST eval
   7 #
   8 # Warning:
   9 # DEST on the remote side will be appended to without questions!
  10 #
  11 # If DEST on the remote side doesn't exist, we'll probably exit immediately.
  12 #
  13 # "ssh" and "eval" are just examples; any valid bash command
  14 # which interpretes arguments in the same way as "eval" will do.
  15 #
  16 # --android or --unix switches the pattern for reading the size from
  17 # the output of "ls -l" (either on Android 2.2 or usual Unix, GNU/Linux).
  18 # By default, we assume you are connecting to an Android (with DroidSSHd).
  19
  20 # Licensed to all under AGPL as published by FSF.
  21 # Copyright (C) 2012 by Ivan Zakharyaschev imz at altlinux.org
  22
  23 readonly SRC="$1"
  24 shift
  25
  26 case "$1" in
  27     --unix)
  28         shift
  29         readonly readSizeRemote=readSizeUnixls
  30         ;;
  31     --android)
  32         shift
  33         readonly readSizeRemote=readSizeAndroidls
  34         ;;
  35     *)
  36         readonly readSizeRemote=readSizeAndroidls
  37         ;;
  38 esac
  39
  40 readonly DEST="$1"
  41 shift
  42
  43 readonly RSH="$1"
  44 shift
  45 case "$RSH" in
  46     ssh)
  47         RSH() {
  48             ssh -e none "$@"
  49         }
  50         ;;
  51     *)
  52         RSH() {
  53             "$RSH" "$@"
  54         }
  55         ;;
  56 esac
  57
  58 readSizeUnixls() {
  59     # The columns of "ls -l" output on GNU/Linux:
  60     local perms links user group size rest
  61     read perms links user group size rest \
  62         && echo "$size"
  63 }
  64
  65 readSizeAndroidls() {
  66     # "ls -l" output on Android 2.2 (Galaxy S) misses one column:
  67     local perms user group size rest
  68     read perms user group size rest \
  69         && echo "$size"
  70 }
  71
  72 # Other (non)possibilities to get the size of a file:
  73 # * "ls -s" is in blocks, but I want bytes;
  74 # * "stat" is missing on Android (2.2).
  75
  76 # If SRC doesn't exist, we'll exit before doing anything else.
  77 SRCsize="$(ls -l "$SRC" | readSizeUnixls)" || exit $?
  78
  79 datapipe="$(mktemp --dry-run)"
  80 rm_datapipe() {
  81     rm -f "$datapipe"
  82 }
  83 trap rm_datapipe EXIT
  84 mkfifo "$datapipe"
  85
  86 # TODO: the problem here: the value $DEST should be protected from an expansion by the remote shell.
  87 RSH "$@" "ls -l $DEST && cat >> $DEST" < "$datapipe" | \
  88 {
  89     DESTsize="$($readSizeRemote)" || exit $?
  90     tail -c +$((DESTsize+1)) "$SRC" | pv --wait --size $((SRCsize-DESTsize))
  91 } > "$datapipe"