user-tools/args2env

   1 #!/usr/bin/env perl
   2
   3 =pod
   4
   5 =head1 NAME
   6
   7 args2env - Turns command arguments into environment variables and executes command with the remained arguments
   8
   9 =head1 SYNOPSIS
  10
  11 args2env [I<OPTIONS>] I<COMMAND> I<ARG_1> I<ARG_2> ... I<ARG_R2> I<ARG_R1>
  12
  13 =head1 DESCRIPTION
  14
  15 =head1 OPTIONS
  16
  17 =over 4
  18
  19 =item -a, --arg I<NUM>
  20
  21 Move the I<NUM>th argument to the environment by the name B<< ARG_I<NUM> >>
  22 (may be overridden by B<--template> option).
  23 Counting starts from 1.
  24 The 0th argument would be the I<COMMAND> itself.
  25 I<NUM> may be negative number, in which case it's counted from the end backwards.
  26
  27 =item -r, --right-arg I<NUM>
  28
  29 Same as B<< --arg -I<NUM> >>.
  30
  31 =item -A, --all
  32
  33 Move all arguments to environment.
  34
  35 =item -k, --keep I<NUM>
  36
  37 Keep the first I<NUM> arguments as arguments, and move the rest of them to environment.
  38 Don't use it with B<-A>, B<-a>, or B<-r>.
  39
  40 =item -t, --template I<TEMPLATE>
  41
  42 How to name environment variables?
  43 Must contain a B<%d> macro.
  44 Default is B<ARG_%d>.
  45 So the value of argument given by B<--arg 1> goes to B<ARG_1> variable.
  46
  47 =item -nt, --negative-template I<TEMPLATE>
  48
  49 How to name environment variables for arguments specified by negative number?
  50 Must contain a B<%d> macro.
  51 Default is B<ARG_R%d>, B<R> is for "right", because this arg is counted from the right.
  52 So the value of argument given by B<--arg -1> goes to B<ARG_R1> variable.
  53
  54 =item -s, --set I<NAME>=I<NUM>
  55
  56 Set I<NAME> variable to the I<NUM>th argument (negative numbers also may be given)
  57 and remove the argument from the argument list (keeping the numbering of remaining arguments unchanged).
  58 Number-based variables (B<< ARG_I<n> >> and B<< ARG_RI<n> >>) are still available.
  59
  60 =back
  61
  62 =head1 SEE ALSO
  63
  64 args2stdin(1)
  65
  66 =cut
  67
  68
  69 use Data::Dumper;
  70 use Errno qw/:POSIX/;
  71 use Getopt::Long qw/:config no_ignore_case no_bundling no_getopt_compat no_auto_abbrev require_order/;
  72 use Pod::Usage;
  73 no if ($] >= 5.018), 'warnings' => 'experimental::smartmatch';
  74
  75 @args_to_move = ();
  76 @OptSetenv = ();
  77 $OptKeepArgs = undef;
  78 %env_names = ();
  79 $envname_template = 'ARG_%d';
  80 $negative_envname_template = 'ARG_R%d';
  81
  82 GetOptions(
  83         'a|arg=i@' => \@args_to_move,
  84         'A|all' => sub { $OptKeepArgs = 0; },
  85         'k|keep=i' => \$OptKeepArgs,
  86         'r|right-arg=i@' => sub {
  87                 my ($getopt, $param) = @_;
  88                 push @args_to_move, -$param;
  89         },
  90         's|set=s@' => \@OptSetenv,
  91         't|template=s' => \$envname_template,
  92         'nt|negative-template=s' => \$negative_envname_template,
  93         'help' => sub { pod2usage(-exitval=>0, -verbose=>99); },
  94 ) or pod2usage(-exitval=>2, -verbose=>99);
  95
  96 if(defined $OptKeepArgs)
  97 {
  98         @args_to_move = (($OptKeepArgs+1) .. $#ARGV);
  99 }
 100
 101 for my $setenv (@OptSetenv)
 102 {
 103         if(my ($name, $num) = $setenv =~ /^([^=]+)=(-?\d+)$/)
 104         {
 105                 push @args_to_move, $num;
 106                 $env_names{$num} = $name;
 107         }
 108         else
 109         {
 110                 die "$0: wrong --set option: $setenv\n";
 111         }
 112 }
 113
 114 if(grep {$_ == 0} @args_to_move)
 115 {
 116         warn "The 0th argument is the command itself, better not to remove.\n";
 117         pod2usage(-exitval=>2, -verbose=>99);
 118 }
 119
 120 for my $arg_num (1..$#ARGV)
 121 {
 122         if(grep {$_ > 0 ? ($arg_num == $_) : ($arg_num == scalar(@ARGV)+$_)} @args_to_move)
 123         {
 124                 my $arg_num_neg = $arg_num - scalar(@ARGV);
 125                 for my $n ($arg_num, $arg_num_neg)
 126                 {
 127                         $ENV{$env_names{$n}} = $ARGV[$arg_num] if defined $env_names{$n};
 128                 }
 129                 my $envname_pos = sprintf $envname_template, $arg_num;
 130                 my $envname_neg = sprintf $negative_envname_template, abs $arg_num_neg;
 131                 $ENV{$envname_pos} = $ARGV[$arg_num];
 132                 $ENV{$envname_neg} = $ARGV[$arg_num];
 133                 $ARGV[$arg_num] = undef;
 134         }
 135 }
 136 @ARGV = grep {defined} @ARGV;
 137
 138 exec {$ARGV[0]} @ARGV;
 139 ($errno, $errstr) = (int $!, $!);
 140 warn "$0: ${ARGV[0]}: $errstr\n";
 141 exit 125+$errno;