127 lines
		
	
	
	
		
			2.5 KiB
			
		
	
	
	
		
			Text
		
	
	
	
	
	
		
		
			
		
	
	
			127 lines
		
	
	
	
		
			2.5 KiB
			
		
	
	
	
		
			Text
		
	
	
	
	
	
|   | #!/usr/bin/perl -w | ||
|  | # | ||
|  | # Clean a text file -- or directory of text files -- of stealth whitespace. | ||
|  | # WARNING: this can be a highly destructive operation.  Use with caution. | ||
|  | # | ||
|  | 
 | ||
|  | use bytes; | ||
|  | use File::Basename; | ||
|  | 
 | ||
|  | # | ||
|  | # Clean up space-tab sequences, either by removing spaces or | ||
|  | # replacing them with tabs. | ||
|  | sub clean_space_tabs($) | ||
|  | { | ||
|  |     no bytes;			# Tab alignment depends on characters | ||
|  | 
 | ||
|  |     my($li) = @_; | ||
|  |     my($lo) = ''; | ||
|  |     my $pos = 0; | ||
|  |     my $nsp = 0; | ||
|  |     my($i, $c); | ||
|  | 
 | ||
|  |     for ($i = 0; $i < length($li); $i++) { | ||
|  | 	$c = substr($li, $i, 1); | ||
|  | 	if ($c eq "\t") { | ||
|  | 	    my $npos = ($pos+$nsp+8) & ~7; | ||
|  | 	    my $ntab = ($npos >> 3) - ($pos >> 3); | ||
|  | 	    $lo .= "\t" x $ntab; | ||
|  | 	    $pos = $npos; | ||
|  | 	    $nsp = 0; | ||
|  | 	} elsif ($c eq "\n" || $c eq "\r") { | ||
|  | 	    $lo .= " " x $nsp; | ||
|  | 	    $pos += $nsp; | ||
|  | 	    $nsp = 0; | ||
|  | 	    $lo .= $c; | ||
|  | 	    $pos = 0; | ||
|  | 	} elsif ($c eq " ") { | ||
|  | 	    $nsp++; | ||
|  | 	} else { | ||
|  | 	    $lo .= " " x $nsp; | ||
|  | 	    $pos += $nsp; | ||
|  | 	    $nsp = 0; | ||
|  | 	    $lo .= $c; | ||
|  | 	    $pos++; | ||
|  | 	} | ||
|  |     } | ||
|  |     $lo .= " " x $nsp; | ||
|  |     return $lo; | ||
|  | } | ||
|  | 
 | ||
|  | $name = basename($0); | ||
|  | 
 | ||
|  | foreach $f ( @ARGV ) { | ||
|  |     print STDERR "$name: $f\n"; | ||
|  | 
 | ||
|  |     if (! -f $f) { | ||
|  | 	print STDERR "$f: not a file\n"; | ||
|  | 	next; | ||
|  |     } | ||
|  | 
 | ||
|  |     if (!open(FILE, '+<', $f)) { | ||
|  | 	print STDERR "$name: Cannot open file: $f: $!\n"; | ||
|  | 	next; | ||
|  |     } | ||
|  | 
 | ||
|  |     binmode FILE; | ||
|  | 
 | ||
|  |     # First, verify that it is not a binary file; consider any file | ||
|  |     # with a zero byte to be a binary file.  Is there any better, or | ||
|  |     # additional, heuristic that should be applied? | ||
|  |     $is_binary = 0; | ||
|  | 
 | ||
|  |     while (read(FILE, $data, 65536) > 0) { | ||
|  | 	if ($data =~ /\0/) { | ||
|  | 	    $is_binary = 1; | ||
|  | 	    last; | ||
|  | 	} | ||
|  |     } | ||
|  | 
 | ||
|  |     if ($is_binary) { | ||
|  | 	print STDERR "$name: $f: binary file\n"; | ||
|  | 	next; | ||
|  |     } | ||
|  | 
 | ||
|  |     seek(FILE, 0, 0); | ||
|  | 
 | ||
|  |     $in_bytes = 0; | ||
|  |     $out_bytes = 0; | ||
|  |     $blank_bytes = 0; | ||
|  | 
 | ||
|  |     @blanks = (); | ||
|  |     @lines  = (); | ||
|  | 
 | ||
|  |     while ( defined($line = <FILE>) ) { | ||
|  | 	$in_bytes += length($line); | ||
|  | 	$line =~ s/[ \t\r]*$//;		# Remove trailing spaces | ||
|  | 	$line = clean_space_tabs($line); | ||
|  | 
 | ||
|  | 	if ( $line eq "\n" ) { | ||
|  | 	    push(@blanks, $line); | ||
|  | 	    $blank_bytes += length($line); | ||
|  | 	} else { | ||
|  | 	    push(@lines, @blanks); | ||
|  | 	    $out_bytes += $blank_bytes; | ||
|  | 	    push(@lines, $line); | ||
|  | 	    $out_bytes += length($line); | ||
|  | 	    @blanks = (); | ||
|  | 	    $blank_bytes = 0; | ||
|  | 	} | ||
|  |     } | ||
|  | 
 | ||
|  |     # Any blanks at the end of the file are discarded | ||
|  | 
 | ||
|  |     if ($in_bytes != $out_bytes) { | ||
|  | 	# Only write to the file if changed | ||
|  | 	seek(FILE, 0, 0); | ||
|  | 	print FILE @lines; | ||
|  | 
 | ||
|  | 	if ( !defined($where = tell(FILE)) || | ||
|  | 	     !truncate(FILE, $where) ) { | ||
|  | 	    die "$name: Failed to truncate modified file: $f: $!\n"; | ||
|  | 	} | ||
|  |     } | ||
|  | 
 | ||
|  |     close(FILE); | ||
|  | } |