#!/usr/bin/perl
#
# Display ascii table
# (Some unix systems have an 'ascii' man page which displays
#  an ascii table; mine doesn't, so I cooked this up)
# takes optional format string
# Usage: ascii [D|a|k|d|b|h]...
# D=Description a=abbreviation k=Keyboard d=Decimal b=Binary h=Hex
# e.g.: ascii hD
# (Default is "ha")
#


use strict;
use warnings;

my $display = @ARGV ? join('', @ARGV) : "ha";
$display =~ tr/-//d;

my @names = qw(Description Abbr Keybd Dec Binary Hex);
my @lengths=qw(-21           -3    -7   3      8   2);
my %lengths; @lengths{@names} = @lengths;
my %show;
my @show = qw(D a k d b h);
@show{@show} = @names;
my $show_str = join("|", @show);

my $usage_str = <<EOT;
Usage: ascii [$show_str]...
D = description
a = abbreviation
k = keybd
d = decimal
b = binary
h = hex
(Default: ha)
EOT

my @display = map { $show{$_} || die "Bad field $_\n$usage_str"
                  } split '', $display;
die "No fields to display\n" unless @display;

my @ascii;
while (<DATA>) {
 chomp;
 next if /^#/ or /^\s*$/;
 my @fields;
 # Read in pipe delimited file (pipes are escaped)
 push @fields, $1 while /((?:\\.|[^|])+)/g;
 s/\\(.)/$1/g for @fields;
 my %fields; @fields{@names} = @fields;
 push @ascii, \%fields;
}

my $max = 70;
my $spaces = 3;
my $hdr = ' ' x $spaces;
my $hdr_txt = sprintf
  join('',
       map { "%-" . (abs($lengths{$_})+$spaces) ."s" } @display
      ),
  @display;
$hdr .= $hdr_txt while length($hdr.$hdr_txt)-$spaces <= $max;
print "$hdr\n";

my $line = '';
for my $asc (@ascii) {
  my $tmp_line = '';
  for my $fld (@display) {
    $tmp_line .= " - " if $tmp_line;
    $tmp_line .= sprintf("%$lengths{$fld}s", $asc->{$fld});
  }
  if ((length($line) + length($tmp_line) + 3) > $max) {
    print "$line\n";
    $line = "   $tmp_line";
  } else {
    $line .= "   $tmp_line";
  }
}
print "$line\n" if $line;
__DATA__
# Description|Abbrev|Keybd|Decimal|Binary|Hex
Null|NUL|Ctrl @|0|00000000|00
Start of Heading|SOH|Ctrl A|1|00000001|01
Start of Text|STX|Ctrl B|2|00000010|02
End of Text|ETX|Ctrl C|3|00000011|03
End of Transmit|EOT|Ctrl D|4|00000100|04
Enquiry|ENQ|Ctrl E|5|00000101|05
Acknowledge|ACK|Ctrl F|6|00000110|06
Bell|BEL|Ctrl G|7|00000111|07
Back Space|BS|Ctrl H|8|00001000|08
Horizontal Tab|TAB|Ctrl I|9|00001001|09
Line Feed|LF|Ctrl J|10|00001010|0A
Vertical Tab|VT|Ctrl K|11|00001011|0B
Form Feed|FF|Ctrl L|12|00001100|0C
Carriage Return|CR|Ctrl M|13|00001101|0D
Shift Out|SO|Ctrl N|14|00001110|0E
Shift In|SI|Ctrl O|15|00001111|0F
Data Line Escape|DLE|Ctrl P|16|00010000|10
Device Control 1|DC1|Ctrl Q|17|00010001|11
Device Control 2|DC2|Ctrl R|18|00010010|12
Device Control 3|DC3|Ctrl S|19|00010011|13
Device Control 4|DC4|Ctrl T|20|00010100|14
Negative Acknowledge|NAK|Ctrl U|21|00010101|15
Synchronous Idle|SYN|Ctrl V|22|00010110|16
End of Transmit Block|ETB|Ctrl W|23|00010111|17
Cancel|CAN|Ctrl X|24|00011000|18
End of Medium|EM|Ctrl Y|25|00011001|19
Substitute|SUB|Ctrl Z|26|00011010|1A
Escape|ESC|Ctrl [|27|00011011|1B
File Separator|FS|Ctrl \\|28|00011100|1C
Group Separator|GS|Ctrl ]|29|00011101|1D
Record Separator|RS|Ctrl ^|30|00011110|1E
Unit Separator|US|Ctrl _|31|00011111|1F
Space| | |32|00100000|20
Exclamation Point|!|Shift 1|33|00100001|21
Double Quote|"|Shift `|34|00100010|22
Pound/Number Sign|#|Shift 3|35|00100011|23
Dollar Sign|$|Shift 4|36|00100100|24
Percent Sign|%|Shift 5|37|00100101|25
Ampersand|&|Shift 7|38|00100110|26
Single Quote|'|'|39|00100111|27
Left Parenthesis|(|(|40|00101000|28
Right Parenthesis|)|)|41|00101001|29
Asterisk|*|*|42|00101010|2A
Plus|+|+|43|00101011|2B
Comma|,|,|44|00101100|2C
Hyphen / Minus Sign|-|-|45|00101101|2D
Period|.|.|46|00101110|2E
Forward Slash|/|/|47|00101111|2F
Zero Digit|0|0|48|00110000|30
One Digit|1|1|49|00110001|31
Two Digit|2|2|50|00110010|32
Three Digit|3|3|51|00110011|33
Four Digit|4|4|52|00110100|34
Five Digit|5|5|53|00110101|35
Six Digit|6|6|54|00110110|36
Seven Digit|7|7|55|00110111|37
Eight Digit|8|8|56|00111000|38
Nine Digit|9|9|57|00111001|39
Colon|:|Shift ;|58|00111010|3A
Semicolon|;|;|59|00111011|3B
Less-Than Sign|<|Shift ,|60|00111100|3C
Equals Sign|=|=|61|00111101|3D
Greater-Than Sign|>|Shift .|62|00111110|3E
Question Mark|?|Shift /|63|00111111|3F
At Sign|@|Shift 2|64|01000000|40
Capital A|A|Shift A|65|01000001|41
Capital B|B|Shift B|66|01000010|42
Capital C|C|Shift C|67|01000011|43
Capital D|D|Shift D|68|01000100|44
Capital E|E|Shift E|69|01000101|45
Capital F|F|Shift F|70|01000110|46
Capital G|G|Shift G|71|01000111|47
Capital H|H|Shift H|72|01001000|48
Capital I|I|Shift I|73|01001001|49
Capital J|J|Shift J|74|01001010|4A
Capital K|K|Shift K|75|01001011|4B
Capital L|L|Shift L|76|01001100|4C
Capital M|M|Shift M|77|01001101|4D
Capital N|N|Shift N|78|01001110|4E
Capital O|O|Shift O|79|01001111|4F
Capital P|P|Shift P|80|01010000|50
Capital Q|Q|Shift Q|81|01010001|51
Capital R|R|Shift R|82|01010010|52
Capital S|S|Shift S|83|01010011|53
Capital T|T|Shift T|84|01010100|54
Capital U|U|Shift U|85|01010101|55
Capital V|V|Shift V|86|01010110|56
Capital W|W|Shift W|87|01010111|57
Capital X|X|Shift X|88|01011000|58
Capital Y|Y|Shift Y|89|01011001|59
Capital Z|Z|Shift Z|90|01011010|5A
Left Bracket|[|[|91|01011011|5B
Backward Slash|\\|\\|92|01011100|5C
Right Bracket|]|]|93|01011101|5D
Caret|^|Shift 6|94|01011110|5E
Underscore|_|Shift -|95|01011111|5F
Back Quote|`|`|96|01100000|60
Lower-case A|a|A|97|01100001|61
Lower-case B|b|B|98|01100010|62
Lower-case C|c|C|99|01100011|63
Lower-case D|d|D|100|01100100|64
Lower-case E|e|E|101|01100101|65
Lower-case F|f|F|102|01100110|66
Lower-case G|g|G|103|01100111|67
Lower-case H|h|H|104|01101000|68
Lower-case I|I|I|105|01101001|69
Lower-case J|j|J|106|01101010|6A
Lower-case K|k|K|107|01101011|6B
Lower-case L|l|L|108|01101100|6C
Lower-case M|m|M|109|01101101|6D
Lower-case N|n|N|110|01101110|6E
Lower-case O|o|O|111|01101111|6F
Lower-case P|p|P|112|01110000|70
Lower-case Q|q|Q|113|01110001|71
Lower-case R|r|R|114|01110010|72
Lower-case S|s|S|115|01110011|73
Lower-case T|t|T|116|01110100|74
Lower-case U|u|U|117|01110101|75
Lower-case V|v|V|118|01110110|76
Lower-case W|w|W|119|01110111|77
Lower-case X|x|X|120|01111000|78
Lower-case Y|y|Y|121|01111001|79
Lower-case Z|z|Z|122|01111010|7A
Left Brace|{|Shift [|123|01111011|7B
Vertical Bar|\||Shift \\|124|01111100|7C
Right Brace|}|Shift ]|125|01111101|7D
Tilde|~|Shift `|126|01111110|7E
Delete|Del|Del|127|01111111|7F