[PATCH 12/19] gitweb: Parse two-line from-file/to-file diff header in git_patchset_body

[Jakub Narebski <jnareb@gmail.com>]

Parse two-line from-file/to-file unified diff header in
git_patchset_body directly, instead of leaving pretty-printing to
format_diff_line function.  Hashes as from-file/to-file are replaced
by proper from-file and to-file names (from $diffinfo); in the future
we can put hyperlinks there.  This makes possible to do blobdiff with
only blobs hashes.

The lines in two-line unified diff header have now class "from_file"
and "to_file"; the style is chosen to match previous output (classes
"rem" and "add" because of '-' and '+' as first character of patch
line).

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
---
 gitweb/gitweb.css  |    2 ++
 gitweb/gitweb.perl |   18 +++++++++++++++++-
 2 files changed, 19 insertions(+), 1 deletions(-)

diff --git a/gitweb/gitweb.css b/gitweb/gitweb.css
index 5eaa24f..0912361 100644
--- a/gitweb/gitweb.css
+++ b/gitweb/gitweb.css
@@ -273,10 +273,12 @@ td.mode {
 	font-family: monospace;
 }
 
+div.diff.to_file,
 div.diff.add {
 	color: #008800;
 }
 
+div.diff.from_file,
 div.diff.rem {
 	color: #cc0000;
 }
diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 461ebcd..9222e30 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -1706,8 +1706,24 @@ sub git_patchset_body {
 
 
 		if ($in_header && $patch_line =~ m/^---/) {
-			#print "</div>\n"
+			#print "</div>\n"; # class="diff extended_header"
 			$in_header = 0;
+
+			my $file = $diffinfo->{'from_file'};
+			$file  ||= $diffinfo->{'file'};
+			$patch_line =~ s|a/[0-9a-fA-F]{40}|a/$file|g;
+			print "<div class=\"diff from_file\">" . esc_html($patch_line) . "</div>\n";
+
+			$patch_line = <$fd>;
+			chomp $patch_line;
+
+			#$patch_line =~ m/^+++/;
+			$file    = $diffinfo->{'to_file'};
+			$file  ||= $diffinfo->{'file'};
+			$patch_line =~ s|b/[0-9a-fA-F]{40}|b/$file|g;
+			print "<div class=\"diff to_file\">" . esc_html($patch_line) . "</div>\n";
+
+			next LINE;
 		}
 		next LINE if $in_header;
 
-- 
1.4.1.1