# findEmptyFiles.pl reports all files in a folder with a size of 0 bytes.
# Original code written 24-sep-1999 by Frank Brown.

require "ctime.pl";

### global variables: ###

$bDebug = 0;
$sAppName = "findEmptyFiles";
$sDefRptFile = $sAppName . ".rpt";
$nDirsRead = 0;
$nEmptyFiles = 0;
$nFilesRead = 0;
$sNow = &ctime(time); chop $sNow;
$bRecurse = 0;
$sRoot = "";
$sTmpDir = $ENV{'TEMP'};
$sRptFile = "";
$sVersion = "1.0";

### let's go:

MAIN:

unless ($#ARGV + 1) {
  die "No directory on command line.\n";	# somebody give me an arg!
  }

&ParseCmdArgs();

if ($sRoot eq "") { die "Root folder missing from command line"; }

print "$sAppName $sVersion starting on $sNow...\n";

&ProcessDir($sRoot);

$sNow = &ctime(time);
print "\n$sAppName $sVersion finished at $sNow";

if ($nEmptyFiles == 0) { print "No empty files found.\n"; goto _noEmpty; }

$sMsg = "$sAppName: $nEmptyFiles empty file";
if ($nEmptyFiles > 1) { $sMsg .= "s"; }
$sMsg .= " found.\n";
print $sMsg;

if ($sRptFile ne "") { &WriteReport(); }

_noEmpty:
$sFword = "file";
if ($nFilesRead > 1) { $sFword .= "s"; }
$sDirWord = "folder";
if ($nDirsRead > 1) { $sDirWord .= "s"; }
print "Processed $nFilesRead $sFword in $nDirsRead $sDirWord.\n";

exit;

######## subroutines start here: #########

sub Help {
  print "\n$sAppName $sVersion lists files with size of 0 bytes.\n\n";
  print "usage: $sAppName [/s] [/out=reportFile] dir\n\n";
  print "/s\trecurse through subdirectories\n";
  print "/out\twrite report file\n";
  }

sub ParseCmdArgs {
  while (@ARGV) {
    $_ = shift @ARGV;
    if ($bDebug) {
      print "debug: parsing cmdline arg $_\n";
      }
    if (/^[\/\-]/) {				# is arg a switch?
      $arg = substr($_,1,3);
      $arg =~ tr/A-Z/a-z/;			# lowercase arg
      if ($arg eq "deb") { $bDebug = 1; }
      if ($bDebug) { print "dbg: arg=$arg\n"; }
      if ($arg eq "hel" || substr($arg,0,1) eq '?') { &Help(); exit; }
      if (substr($arg,0,1) eq 's') { $bRecurse = 1; }
      if ($arg eq "out") {
        $i = index($_,"=");
        $i++;
        $sRptFile = substr($_,$i);
        if ($sRptFile eq "") { $sRptFile = $sDefRptFile; }
        }
      }
    else {
      $sRoot = $_;
      }
    }
  if ($bDebug) {
    print "dbg: bDebug = $bDebug\n";
    print "dbg: sRoot = $sRoot\n";
    print "dbg: recurse = $bRecurse\n";
    if ($sRptFile ne "") { print "dbg: sRptFile = $sRptFile\n"; }
    }
  }

sub ProcessDir {
  local $sDir = $_[0];
  if (!length($sDir)) { return; }
  if ($sDir eq "." || $sDir eq "..") { return; }

  print "processing dir $sDir...\n";

  if (!opendir(FLDR,$sDir)) { print "Can't open folder $sDir\n"; return; }
  ++$nDirsRead;
  local @filenames = readdir(FLDR);				# get list of files
  closedir(FLDR);
  foreach (@filenames) {
    if ($_ eq "." || $_ eq "..") { next; }
    $sFile = $sDir;
    if ($sDir !~ m/\\+$/) { $sFile .= "\\"; }			# if no \\ then add one
    $sFile .= $_;
    if ( -f $sFile) { &ProcessFile($sFile); } 
    else { if ($bRecurse) { &ProcessDir($sFile); } }
    }

  }

sub ProcessFile {
  local $sChkFile = $_[0];
  local $nSize;
  ++$nFilesRead;

  $nSize = (stat($sChkFile))[7];
  if ($nSize == 0) {
    print " $sChkFile\n";		# prepend a space so it's easier to see on screen
    push(@files,$sChkFile);
    ++$nEmptyFiles;
    }
  }

sub WriteReport {
  local $sLine = "";
  local $sFile = ">" . $sRptFile;
  if (!open(RPT,$sFile)) { print "Can't open report file $sRptFile: $!"; return; }
  local $nTotal = @files;
  @sortedFiles = sort @files;
  $sNow = &ctime(time);
  print RPT "$sAppName $sVersion empty file report $sNow\n";
  print RPT "Found $nTotal empty files in $sRoot:\n\n";
  foreach (@sortedFiles) {
    print RPT "$_\n";
    }
  print RPT "\n*** end of report ***\n";
  close RPT;

  print "Created report $sRptFile\n";
  }