user-tools/multicmd

   1 #!/usr/bin/env perl
   2
   3 =pod
   4
   5 =head1 NAME
   6
   7 multicmd - Run multiple commands in series
   8
   9 =head1 SYNOPSIS
  10
  11 multicmd [I<OPTIONS>] [--] I<COMMAND-1> I<ARGS-1> ";" I<COMMAND-2> I<ARGS-2> ";" ...
  12
  13 Run I<COMMAND-1>, I<COMMAND-2>, ... I<COMMAND-n> after each other,
  14 similarly like shells would do, except not involving any shell.
  15
  16 =head1 OPTIONS
  17
  18 =over 4
  19
  20 =item -d, --delimiter I<STRING>
  21
  22 Set command delimiter to I<STRING>.
  23 Default is a literal C<;> semicolon.
  24 Probably need to shell-escape.
  25 If you want C<--> (double dash) for delimiter, to avoid confusion, put it as:
  26 C<--delimiter=-->.
  27
  28 =item -e, --errexit
  29
  30 Exit if a command did not run successfully (ie. non-zero exit status or signaled)
  31 and do not run further commands.
  32 Similar to bash(1)'s errexit (set -e) mode.
  33 multicmd(1)'s exit code will be the failed command exit code
  34 (128+B<n> if terminated by a signal B<n>).
  35
  36 =back
  37
  38 =head1 CAVEATS
  39
  40 Note, that C<;> (or the non-default delimiter set by B<--delimiter>) is a shell meta-char
  41 in your shell, so you need to escape/quote it, but it's a separate literal argument
  42 when you call multicmd(1) in other layers (eg. execve(2)),
  43 so don't just stick to the preceding word. Ie:
  44
  45 B<WRONG>: multicmd date\; ls
  46
  47 B<WRONG>: multicmd 'date; ls'
  48
  49 B<WRONG>: multicmd 'date ; ls'
  50
  51 B<CORRECT>: multicmd date \; ls
  52
  53 B<CORRECT>: multicmd date ';' ls
  54
  55 =head1 EXIT STATUS
  56
  57 multicmd(1) exit with the exit code of the last command.
  58
  59 =cut
  60
  61
  62 use Getopt::Long qw/:config no_ignore_case no_bundling no_getopt_compat no_auto_abbrev require_order pass_through/;
  63 use Pod::Usage;
  64 use Data::Dumper;
  65 use POSIX;
  66
  67 $Delimiter = ';';
  68 $Errexit = 0;
  69
  70 GetOptions(
  71         'd|delimiter=s' => \$Delimiter,
  72         'e|errexit!' => \$Errexit,
  73         'help' => sub { pod2usage(-exitval=>0, -verbose=>99); },
  74 ) or pod2usage(-exitval=>2, -verbose=>99);
  75
  76 # Getopt's pass_through mode leaves "--" there
  77 shift @ARGV if $ARGV[0] eq '--';
  78
  79 if(not @ARGV)
  80 {
  81         pod2usage(-exitval=>2, -verbose=>99);
  82 }
  83
  84 @cmd_args = ([]);
  85 $cmd_idx = 0;
  86
  87 for my $arg (@ARGV)
  88 {
  89         if($arg eq $Delimiter)
  90         {
  91                 $cmd_idx++;
  92                 $cmd_args[$cmd_idx] = [];
  93         }
  94         else
  95         {
  96                 push @{$cmd_args[$cmd_idx]}, $arg;
  97         }
  98 }
  99
 100 # filter out empty commands
 101 @cmd_args = grep {@$_} @cmd_args;
 102
 103 $last_cmd_ref = pop @cmd_args;
 104
 105 for my $cmd_ref (@cmd_args)
 106 {
 107         system @$cmd_ref;
 108         my $error_code = ${^CHILD_ERROR_NATIVE};
 109         my $sys_errmsg = $!;
 110         my $sys_errno = int $!;
 111         my $exit_status = 0;
 112
 113         if($error_code == -1)
 114         {
 115                 warn "$0: $cmd_ref->[0]: $sys_errmsg\n";
 116                 $exit_status = 125 + $sys_errno;  # "file not found" becomes 127.
 117         }
 118         else
 119         {
 120                 if(WIFSIGNALED($error_code)) { $exit_status = 128 + WTERMSIG($error_code); }
 121                 else { $exit_status = WEXITSTATUS($error_code); }
 122         }
 123
 124         if($Errexit and $exit_status != 0)
 125         {
 126                 exit $exit_status;
 127         }
 128 }
 129
 130 exec {$last_cmd_ref->[0]} @$last_cmd_ref;
 131 # if last command not found:
 132 ($errno, $errstr) = (int $!, $!);
 133 warn "$0: $last_cmd_ref->[0]: $errstr\n";
 134 exit 125+$errno;