mdw@git.distorted.org.uk Git - zx-fizzbuzz/blob - gluep

   1 #! /usr/bin/perl
   2
   3 use autodie;
   4
   5 sub intify ($) {
   6   my ($n) = @_;
   7   if ($n =~ /^0/) { $n = oct $n; }
   8   return $n;
   9 }
  10
  11 my $MEM = "";
  12 my $BASE = 0x4009;
  13 my $LIMIT = 0x8000;
  14
  15 for my $a (@ARGV) {
  16   $a =~ /^(\w+):(.*)$/ or die "bad spec ADDR:FILE";
  17   my $addr = intify $1;
  18   my $file = $2;
  19
  20   my $body = "";
  21   open my $fh, "<", $file;
  22   READ: for (;;) {
  23     sysread $fh, my $buf, 4096;
  24     last READ unless length $buf;
  25     $body .= $buf;
  26   }
  27   close $fh;
  28
  29   $addr >= $BASE && $LIMIT >= $addr + length $body
  30     or die "out of bounds";
  31
  32   $addr -= $BASE;
  33   my $end = $addr + length $body;
  34   my $before = $addr > length $MEM
  35     ? $MEM . "\0" x ($addr - length $MEM)
  36     : substr $MEM, 0, $addr;
  37   my $after = $end <= length $MEM
  38     ? ""
  39     : substr $MEM, $end;
  40   $MEM = $before . $body . $after;
  41 }
  42
  43 syswrite STDOUT, $MEM;