user-tools/args2stdin

   1 #!/usr/bin/env perl
   2
   3 =pod
   4
   5 =head1 NAME
   6
   7 args2stdin - Turns command arguments into input stream on STDIN
   8
   9 =head1 SYNOPSIS
  10
  11 args2stdin [I<OPTIONS>] I<COMMAND> I<ARG_1> [I<ARG_2> [...]]
  12
  13 =head1 DESCRIPTION
  14
  15 Execute I<COMMAND> command with I<ARG_n> arguments,
  16 except remove those which are specified in I<OPTIONS> and write them on the command's STDIN instead.
  17
  18 =head1 OPTIONS
  19
  20 =over 4
  21
  22 =item -a, --arg I<NUM>
  23
  24 Remove the I<NUM>th argument and write it on STDIN.
  25 Counting starts from 1.
  26 The 0th argument would be the I<COMMAND> itself.
  27 I<NUM> may be negative number, in which case it's counted from the end backwards.
  28
  29 =item -r, --right-arg I<NUM>
  30
  31 Same as B<< --arg -I<NUM> >>.
  32
  33 =item -A, --all
  34
  35 Move all arguments to STDIN.
  36
  37 =item -e, --all-after I<STRING>
  38
  39 I<STRING> marks the end of arguments.
  40 All arguments after this will be passed in STDIN.
  41 This argument won't be passed to I<COMMAND> anywhere.
  42 It's usually C<-->.
  43 args2stdin(1) does not have any default for this, so no particular argument makes the rest of them go to STDIN.
  44
  45 =item -k, --keep I<NUM>
  46
  47 Keep the first I<NUM> arguments as arguments, and move the rest of them.
  48 Don't use it with B<-A>, B<-a>, or B<-r>.
  49
  50 =item -d, --delimiter I<STRING>
  51
  52 Delimit arguments by I<STRING> string.
  53 Default is linefeed (B<\n>).
  54
  55 =item -t, --tab-delimiter
  56
  57 Delimit arguments by TAB char.
  58
  59 =item -0, --null
  60
  61 Delimit arguments by NUL char.
  62
  63 =back
  64
  65 =head1 SEE ALSO
  66
  67 args2env(1)
  68
  69 =cut
  70
  71
  72 use Data::Dumper;
  73 use Errno qw/:POSIX/;
  74 use Getopt::Long qw/:config no_ignore_case no_bundling no_getopt_compat no_auto_abbrev require_order/;
  75 use Pod::Usage;
  76 no if ($] >= 5.018), 'warnings' => 'experimental::smartmatch';
  77
  78 @args_to_move = ();
  79 $OptDelimiter = "\n";
  80 $OptKeepArgs = undef;
  81 $OptEndMark = undef;
  82
  83 GetOptions(
  84         'a|arg=i@' => \@args_to_move,
  85         'A|all' => sub { $OptKeepArgs = 0; },
  86         'k|keep=i' => \$OptKeepArgs,
  87         'r|right-arg=i@' => sub {
  88                 my ($getopt, $param) = @_;
  89                 push @args_to_move, -$param;
  90         },
  91         'e|all-after=s' => \$OptEndMark,
  92         'd|delimiter=s' => \$OptDelimiter,
  93         't|tab-delimiter' => sub { $OptDelimiter = "\t"; },
  94         '0|null' => sub { $OptDelimiter = chr 0; },
  95         'help' => sub { pod2usage(-exitval=>0, -verbose=>99); },
  96 ) or pod2usage(-exitval=>2, -verbose=>99);
  97
  98 if(defined $OptEndMark)
  99 {
 100         my $mark_arg_num = undef;
 101         for my $arg_num (1..$#ARGV)
 102         {
 103                 if(defined $mark_arg_num)
 104                 {
 105                         push @args_to_move, $arg_num-1;
 106                 }
 107                 elsif($ARGV[$arg_num] eq $OptEndMark)
 108                 {
 109                         $mark_arg_num = $arg_num;
 110                 }
 111         }
 112         if(defined $mark_arg_num)
 113         {
 114                 @ARGV = (@ARGV[0..($mark_arg_num-1)], @ARGV[($mark_arg_num+1)..$#ARGV]);
 115         }
 116 }
 117
 118 if(defined $OptKeepArgs)
 119 {
 120         @args_to_move = (($OptKeepArgs+1) .. $#ARGV);
 121 }
 122
 123 if(grep {$_ == 0} @args_to_move)
 124 {
 125         warn "The 0th argument is the command itself, better not to remove.\n";
 126         pod2usage(-exitval=>2, -verbose=>99);
 127 }
 128
 129 pipe($stdin_r, $stdin_w) or die "$0: pipe: $!\n";
 130
 131 for my $arg_num (@args_to_move)
 132 {
 133         print {$stdin_w} $ARGV[$arg_num] . $OptDelimiter;
 134 }
 135 for my $arg_num (@args_to_move)
 136 {
 137         $ARGV[$arg_num] = undef;
 138 }
 139 @ARGV = grep {defined} @ARGV;
 140
 141 close $stdin_w;
 142 open STDIN, '<&=', fileno $stdin_r or die "$0: open: $!\n";
 143
 144 exec {$ARGV[0]} @ARGV;
 145 ($errno, $errstr) = (int $!, $!);
 146 warn "$0: ${ARGV[0]}: $errstr\n";
 147 exit 125+$errno;