1#!/usr/local/bin/perl 2 3use CGI; 4$query = new CGI; 5 6print $query->header; 7print $query->start_html("Save and Restore Example"); 8print "<H1>Save and Restore Example</H1>\n"; 9 10# Here's where we take action on the previous request 11&save_parameters($query) if $query->param('action') eq 'SAVE'; 12$query = &restore_parameters($query) if $query->param('action') eq 'RESTORE'; 13 14# Here's where we create the form 15print $query->start_multipart_form; 16print "Popup 1: ",$query->popup_menu('popup1',[qw{red green purple magenta orange chartreuse brown}]),"\n"; 17print "Popup 2: ",$query->popup_menu('popup2',[qw{lion tiger bear zebra potto wildebeest frog emu gazelle}]),"\n"; 18print "<P>"; 19$default_name = $query->remote_addr . '.sav'; 20print "Save/restore state from file: ",$query->textfield('savefile',$default_name),"\n"; 21print "<P>"; 22print $query->submit('action','SAVE'),$query->submit('action','RESTORE'); 23print "<P>",$query->defaults; 24print $query->endform; 25 26# Here we print out a bit at the end 27print $query->end_html; 28 29sub save_parameters { 30 local($query) = @_; 31 local($filename) = &clean_name($query->param('savefile')); 32 if (open(FILE,">$filename")) { 33 $query->save(FILE); 34 close FILE; 35 print "<STRONG>State has been saved to file $filename</STRONG>\n"; 36 print "<P>If you remember this name you can restore the state later.\n"; 37 } else { 38 print "<STRONG>Error:</STRONG> couldn't write to file $filename: $!\n"; 39 } 40} 41 42sub restore_parameters { 43 local($query) = @_; 44 local($filename) = &clean_name($query->param('savefile')); 45 if (open(FILE,$filename)) { 46 $query = new CGI(FILE); # Throw out the old query, replace it with a new one 47 close FILE; 48 print "<STRONG>State has been restored from file $filename</STRONG>\n"; 49 } else { 50 print "<STRONG>Error:</STRONG> couldn't restore file $filename: $!\n"; 51 } 52 return $query; 53} 54 55 56# Very important subroutine -- get rid of all the naughty 57# metacharacters from the file name. If there are, we 58# complain bitterly and die. 59sub clean_name { 60 local($name) = @_; 61 unless ($name=~/^[\w\._\-]+$/) { 62 print "<STRONG>$name has naughty characters. Only "; 63 print "alphanumerics are allowed. You can't use absolute names.</STRONG>"; 64 die "Attempt to use naughty characters"; 65 } 66 return "WORLD_WRITABLE/$name"; 67} 68