mdw@git.distorted.org.uk Git - distorted-backup/blob - bkpfunc.sh

   1 ### -*-sh-*-
   2 ###
   3 ### Functions for backup clients.
   4 ###
   5 ### (c) 2011 Mark Wooding
   6 ###
   7
   8 ###----- Licensing notice ---------------------------------------------------
   9 ###
  10 ### This program is free software; you can redistribute it and/or modify
  11 ### it under the terms of the GNU General Public License as published by
  12 ### the Free Software Foundation; either version 2 of the License, or
  13 ### (at your option) any later version.
  14 ###
  15 ### This program is distributed in the hope that it will be useful,
  16 ### but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ### GNU General Public License for more details.
  19 ###
  20 ### You should have received a copy of the GNU General Public License
  21 ### along with this program; if not, write to the Free Software Foundation,
  22 ### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23
  24 set -e
  25
  26 ###--------------------------------------------------------------------------
  27 ### Utilities.
  28
  29 QUIS=${0##*/}
  30 fail () { echo >&2 "$QUIS: $*"; exit 1; }
  31
  32 preflight () {
  33   for i in TMPDIR HOST RMT LEVEL LASTDATE ASSET TARGET; do
  34     eval "p=\${BKP_$i+t}"
  35     case "$p" in t) ;; *) fail "environment not correctly configured" ;; esac
  36   done
  37 }
  38
  39 run () {
  40   echo "$*"
  41   "$@"
  42 }
  43
  44 bkpadmin () {
  45   ## bkpadmin COMMAND ARGUMENT ...
  46   ssh $BKP_HOST userv root bkpadmin "$@"
  47 }
  48
  49 datefmt () {
  50   fmt=$1 date=$2
  51   ## Convert the DATE (in ISO8601-ish format, with an optional numeric
  52   ## timezone offset) according to the strftime(3) format FMT.
  53
  54   ## We have Perl available, so you'd think this would be fairly easy.  Alas,
  55   ## not.  The obvious thing to do would be use the Date::Format module, but
  56   ## that's unusably broken.  Consider:
  57   ##
  58   ##   $t0 = 1319934600; $t1 = $t0 + 3600;      # obviously different
  59   ##   for my $i ($t0, $t1)                     # print identically
  60   ##     { print time2str "%a %b %e %H:%M:%S %Y %z\n", $i; }
  61   ##
  62   ## The Date::Parse module seems to work correctly, but isn't installed by
  63   ## default on some of our target platforms.  So we end up doing a lot of
  64   ## the work by hand.
  65
  66   perl -e '
  67     use POSIX;
  68
  69     my ($fmt, $date) = @ARGV;
  70
  71     ## Parse the input date.
  72     my ($yr, $mo, $dy, $hr, $mi, $s, $tz) = $date =~
  73       /^\s*(\d+)-(\d+)-(\d+)\s+(\d+):(\d+):(\d+)(?:\s+)?([-+]\d+)?\s*$/
  74       or die "bad input date `$date'\''";
  75
  76     ## Convert the input date into a time_t.  This is annoyingly fiddly.  If
  77     ## an explicit timezone offset is supplied, do the conversion as UTC, and
  78     ## then apply the timezone correction.  This means that we must hack
  79     ## about with the awful BCD timezone offset.
  80     my $t;
  81     if (!defined $tz) {
  82       $t = mktime $s, $mi, $hr, $dy, $mo - 1, $yr - 1900, undef, undef, -1;
  83     } else {
  84       use integer;
  85       my ($tzsign, $tzabs) = $tz < 0 ? (-1, -$tz) : (+1, $tz);
  86       my $tzoff = $tzsign*(60*($tzabs/100) + ($tzabs%100));
  87       local $ENV{TZ} = "UTC0"; tzset;
  88       $t = mktime $s, $mi, $hr, $dy, $mo - 1, $yr - 1900, undef, undef, 0;
  89       $t -= 60*$tzoff;
  90     }
  91
  92     ## Now format this as requested.
  93     tzset; my @tm = localtime $t;
  94     print strftime $fmt, @tm;
  95     print "\n";
  96   ' "$fmt" "$date"
  97 }
  98
  99 ###----- That's all, folks --------------------------------------------------