1 files changed, 206 insertions, 0 deletions

diff --git a/scripts/cleanpatch b/scripts/cleanpatch
new file mode 100755
index 000000000000..a53f987708f5
--- /dev/null
+++ b/scripts/cleanpatch
@@ -0,0 +1,206 @@
+#!/usr/bin/perl -w
+#
+# Clean a patch file -- or directory of patch 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;
+
+    @lines  = ();
+
+    $in_hunk = 0;
+    $err = 0;
+
+    while ( defined($line = <FILE>) ) {
+        $in_bytes += length($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);
+
+                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);
+}