cvsexportcommit - add -a (add author line) flag, cleanup warnings

This patch adds support for -a which will add an "Author: " line, and possibly
a "Committer: " line to the bottom of the commit message for CVS.

The commit message parser is now a little bit better, and some warnings
have been cleaned up.

Signed-off-by: Junio C Hamano <junkio@cox.net>

Documentation/git-cvsexportcommit.txt

@@ -8,7 +8,7 @@ git-cvsexportcommit - Export a commit to a CVS checkout
 
 SYNOPSIS
 --------
-'git-cvsexportcommit' [-h] [-v] [-c] [-p] [-f] [-m msgprefix] [PARENTCOMMIT] COMMITID
+'git-cvsexportcommit' [-h] [-v] [-c] [-p] [-a] [-f] [-m msgprefix] [PARENTCOMMIT] COMMITID
 
 
 DESCRIPTION
@@ -36,9 +36,13 @@ OPTIONS
 	commit if any hunks fail to apply or there were other problems.
 
 -p::
-	Be pedantic (paranoid) when applying patches. Invokes patch with 
+	Be pedantic (paranoid) when applying patches. Invokes patch with
 	--fuzz=0
 
+-a::
+	Add authorship information. Adds Author line, and Committer (if
+	different from Author) to the message.
+
 -f::
 	Force the merge even if the files are not up to date.
 

git-cvsexportcommit.perl

@@ -16,9 +16,9 @@
     die "GIT_DIR is not defined or is unreadable";
 }
 
-our ($opt_h, $opt_p, $opt_v, $opt_c, $opt_f, $opt_m );
+our ($opt_h, $opt_p, $opt_v, $opt_c, $opt_f, $opt_a, $opt_m );
 
-getopts('hpvcfm:');
+getopts('hpvcfam:');
 
 $opt_h && usage();
 
@@ -29,7 +29,6 @@
 				     TMPDIR => 1,
 				     CLEANUP => 1);
 
-print Dumper(@ARGV);
 # resolve target commit
 my $commit;
 $commit = pop @ARGV;
@@ -53,12 +52,32 @@
 # find parents from the commit itself
 my @commit  = safe_pipe_capture('git-cat-file', 'commit', $commit);
 my @parents;
-foreach my $p (@commit) {
-    if ($p =~ m/^$/) { # end of commit headers, we're done
-	last;
+my $committer;
+my $author;
+my $stage = 'headers'; # headers, msg
+my $title;
+my $msg = '';
+
+foreach my $line (@commit) {
+    chomp $line;
+    if ($stage eq 'headers' && $line eq '') {
+	$stage = 'msg';
+	next;
     }
-    if ($p =~ m/^parent (\w{40})$/) { # found a parent
-	push @parents, $1;
+
+    if ($stage eq 'headers') {
+	if ($line =~ m/^parent (\w{40})$/) { # found a parent
+	    push @parents, $1;
+	} elsif ($line =~ m/^author (.+) \d+ \+\d+$/) {
+	    $author = $1;
+	} elsif ($line =~ m/^committer (.+) \d+ \+\d+$/) {
+	    $committer = $1;
+	}
+    } else {
+	$msg .= $line . "\n";
+	unless ($title) {
+	    $title = $line;
+	}
     }
 }
 
@@ -84,12 +103,18 @@
 
 # grab the commit message
 open(MSG, ">.msg") or die "Cannot open .msg for writing";
-print MSG $opt_m;
+if ($opt_m) {
+    print MSG $opt_m;
+}
+print MSG $msg;
+if ($opt_a) {
+    print MSG "\n\nAuthor: $author\n";
+    if ($author ne $committer) {
+	print MSG "Committer: $committer\n";
+    }
+}
 close MSG;
 
-`git-cat-file commit $commit | sed -e '1,/^\$/d' >> .msg`;
-$? && die "Error extracting the commit message";
-
 my (@afiles, @dfiles, @mfiles, @dirs);
 my @files = safe_pipe_capture('git-diff-tree', '-r', $parent, $commit);
 #print @files;
@@ -233,6 +258,7 @@
 }
 
 print "Commit to CVS\n";
+print "Patch: $title\n";
 my $commitfiles = join(' ', @afiles, @mfiles, @dfiles);
 my $cmd = "cvs commit -F .msg $commitfiles";