From: H. Peter Anvin Date: Mon, 12 Mar 2007 19:16:30 +0000 (-0700) Subject: cleanfile: a script to clean up stealth whitespace X-Git-Tag: v2.6.22-rc1~1007^2~31 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=12b315603a1eb95b4e4ea3389ba44bd7ded0aa35;p=linux-2.6 cleanfile: a script to clean up stealth whitespace This script cleans up various classes of stealth whitespace. In particular, it cleans up: - Whitespace (spaces or tabs)before newline; - DOS line endings (CR before LF); - Space before tab (spaces are deleted or converted to tabs); - Empty lines at end of file. Signed-off-by: H. Peter Anvin Signed-off-by: Sam Ravnborg --- diff --git a/scripts/cleanfile b/scripts/cleanfile new file mode 100755 index 0000000000..f1ba8aa58a --- /dev/null +++ b/scripts/cleanfile @@ -0,0 +1,126 @@ +#!/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 = ) ) { + $in_bytes += length($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); +}