filehound(filespec)

function  filelist =  filehound(filespec)
%============================================================================
% syntax: 
%         filelist =  filehound(filespec)
% or:     filelist =  filehound   
%         for default search for *.m files
%
% description   : recursively examines directories for presence of files 
% 		  matching the filter defined by input parameter 'filespec'
%
% parameters in : filespec = (optional) filter for filenames default = '*.m'
%
% parameters out: filelist = cell array with paths for specified files
%
% filename      : filehound.m
%      
%============================================================================

%============================================================================
% author          : Ronald Ouwerkerk, Johns Hopkins Univ, dept Radiology
%			[e-mail]
%
% started writing : 2001 last update     : 20-02-2001
%
%============================================================================
global fout

%============================================================================
% set default
%============================================================================
if nargin == 0
  filespec = '*.m'
end; 

%============================================================================
% set directory separator for computer type
%============================================================================
comp = computer;
comp = comp(1:2);
switch(comp)
case 'SU',
  usep = '/';
case 'SO',
  usep = '/';
case 'SG',
  usep = '/';
case 'AL',
  usep = '/';
case 'DE',
  usep = '/';
case 'HP',
  usep = '/';
case 'IB',
  usep = '/';
case 'VA',
  usep = '.';
case 'PC',
  usep = '\';
case 'MA',
  usep = ':';
otherwise,
  usep = 'xx';
end


olddir = pwd;
%============================================================================
% Get parent directory to search and filename for collected files
%============================================================================
fileuititle = 'Select directory and filename for report'; 
[filename, pathname] = uiputfile('*.txt', fileuititle)
if isempty(filename)
  filename = 'report.txt'
  pathname = pwd
else
  eval(['cd 'pathname]);
end; 

%============================================================================
% create filename for collected files delete old copies
%============================================================================
topdir = pwd;
outfilename = [topdir, usep, filename]
if exist(outfilename, 'file')
  eval(['delete ',outfilename]);
end;  

%============================================================================
% recursively scan all subdirectories
%============================================================================
filelist = [];
fout = fopen(outfilename,'a');
filelist = scandir(filelist, filespec);
fclose(fout);
eval(['cd 'olddir]);

%============================================================================
% END main
%============================================================================

%============================================================================
% local function scandir
% Scans the present directory and recursively scans all directories below 
%============================================================================
function filelist = scandir(filelist, filespec)
%============================================================================
% define the global file ID
%============================================================================
global fout

%============================================================================
% define set of leagl chars for dirnames
%============================================================================
legalchar = '-_abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890';

%============================================================================
% get dir list
%============================================================================
thisdir = pwd;
thisdirlist = dir(thisdir);

%============================================================================
% find files (not isdir)
%============================================================================
kdir = [thisdirlist(:).isdir];
allfilelist = thisdirlist(~kdir);
nfiles = length(allfilelist);

%============================================================================
% files matching the pattern of filespec
%============================================================================
wildcardpos = findstr(filespec, '*');
k= 1:length(filespec);
k = k(k~=wildcardpos);
filefilter = filespec(k);
listpos = length(filelist);
count = 0;

for filei= 1:nfiles
  fname = allfilelist(filei).name;
  if findstr(filefilter, fname) &  (length(fname) > length(filefilter))        
    filestr = sprintf('%s/%s', thisdir, fname);
    count = count+1;
    filelist{listpos + count} = filestr;
    fprintf(fout,'%s\n', filestr);
  end  
end;

%============================================================================
% find subdirectories
%============================================================================
kdir = [thisdirlist(:).isdir];
thisdirlist = thisdirlist(kdir);
ndirs = length(thisdirlist);

%============================================================================
% scan all subdirectories recursively
%============================================================================
for diri= 1:ndirs
  subdirname = thisdirlist(diri).name;
  if ~strcmp(subdirname, '.') & ~strcmp(subdirname, '..')
     ipos =  ismember(subdirname, legalchar);     
     if length(subdirname(ipos)) < length(subdirname)
       msgstr = sprintf('Skipped directory %s because its name', subdirname);
       msgstr = sprintf('%s contains illegal characters\n',msgstr);
       disp(msgstr) 
     else
       cmdstr = ['cd ', subdirname];
       disp(cmdstr);
       eval(cmdstr);
       filelist = scandir(filelist, filespec);
       cmdstr = ['cd ', thisdir];
       disp(cmdstr);
       eval(cmdstr);
    end;   
  end
end; 
%============================================================================
%END local function scandir
%============================================================================