diff options
Diffstat (limited to 'scripts/cleanpatch')
-rwxr-xr-x | scripts/cleanpatch | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/scripts/cleanpatch b/scripts/cleanpatch new file mode 100755 index 0000000000..9f17552715 --- /dev/null +++ b/scripts/cleanpatch @@ -0,0 +1,260 @@ +#!/usr/bin/env perl +# SPDX-License-Identifier: GPL-2.0 +# +# Clean a patch file -- or directory of patch files -- of stealth whitespace. +# WARNING: this can be a highly destructive operation. Use with caution. +# + +use warnings; +use bytes; +use File::Basename; + +# Default options +$max_width = 79; + +# Clean up space-tab sequences, either by removing spaces or +# replacing them with tabs. +sub clean_space_tabs($) +{ + 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 $lo; +} + +# Compute the visual width of a string +sub strwidth($) { + no bytes; # Tab alignment depends on characters + + my($li) = @_; + my($c, $i); + my $pos = 0; + my $mlen = 0; + + for ($i = 0; $i < length($li); $i++) { + $c = substr($li,$i,1); + if ($c eq "\t") { + $pos = ($pos+8) & ~7; + } elsif ($c eq "\n") { + $mlen = $pos if ($pos > $mlen); + $pos = 0; + } else { + $pos++; + } + } + + $mlen = $pos if ($pos > $mlen); + return $mlen; +} + +$name = basename($0); + +@files = (); + +while (defined($a = shift(@ARGV))) { + if ($a =~ /^-/) { + if ($a eq '-width' || $a eq '-w') { + $max_width = shift(@ARGV)+0; + } else { + print STDERR "Usage: $name [-width #] files...\n"; + exit 1; + } + } else { + push(@files, $a); + } +} + +foreach $f ( @files ) { + print STDERR "$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; + $lineno = 0; + + @lines = (); + + $in_hunk = 0; + $err = 0; + + while ( defined($line = <FILE>) ) { + $lineno++; + $in_bytes += length($line); + + if (!$in_hunk) { + if ($line =~ + /^\@\@\s+\-([0-9]+),([0-9]+)\s+\+([0-9]+),([0-9]+)\s\@\@/) { + $minus_lines = $2; + $plus_lines = $4; + if ($minus_lines || $plus_lines) { + $in_hunk = 1; + @hunk_lines = ($line); + } + } else { + push(@lines, $line); + $out_bytes += length($line); + } + } else { + # We're in a hunk + + if ($line =~ /^\+/) { + $plus_lines--; + + $text = substr($line, 1); + $text =~ s/[ \t\r]*$//; # Remove trailing spaces + $text = clean_space_tabs($text); + + $l_width = strwidth($text); + if ($max_width && $l_width > $max_width) { + print STDERR + "$f:$lineno: adds line exceeds $max_width ", + "characters ($l_width)\n"; + } + + push(@hunk_lines, '+'.$text); + } elsif ($line =~ /^\-/) { + $minus_lines--; + push(@hunk_lines, $line); + } elsif ($line =~ /^ /) { + $plus_lines--; + $minus_lines--; + push(@hunk_lines, $line); + } else { + print STDERR "$name: $f: malformed patch\n"; + $err = 1; + last; + } + + if ($plus_lines < 0 || $minus_lines < 0) { + print STDERR "$name: $f: malformed patch\n"; + $err = 1; + last; + } elsif ($plus_lines == 0 && $minus_lines == 0) { + # End of a hunk. Process this hunk. + my $i; + my $l; + my @h = (); + my $adj = 0; + my $done = 0; + + for ($i = scalar(@hunk_lines)-1; $i > 0; $i--) { + $l = $hunk_lines[$i]; + if (!$done && $l eq "+\n") { + $adj++; # Skip this line + } elsif ($l =~ /^[ +]/) { + $done = 1; + unshift(@h, $l); + } else { + unshift(@h, $l); + } + } + + $l = $hunk_lines[0]; # Hunk header + undef @hunk_lines; # Free memory + + if ($adj) { + die unless + ($l =~ /^\@\@\s+\-([0-9]+),([0-9]+)\s+\+([0-9]+),([0-9]+)\s\@\@(.*)$/); + my $mstart = $1; + my $mlin = $2; + my $pstart = $3; + my $plin = $4; + my $tail = $5; # doesn't include the final newline + + $l = sprintf("@@ -%d,%d +%d,%d @@%s\n", + $mstart, $mlin, $pstart, $plin-$adj, + $tail); + } + unshift(@h, $l); + + # Transfer to the output array + foreach $l (@h) { + $out_bytes += length($l); + push(@lines, $l); + } + + $in_hunk = 0; + } + } + } + + if ($in_hunk) { + print STDERR "$name: $f: malformed patch\n"; + $err = 1; + } + + if (!$err) { + 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); +} |