[RFC/PATCH v4 08/49] Git/Packet: add capability functions

[Christian Couder <christian.couder@xxxxxxxxx>]

Add functions to help read and write capabilities.
Use these functions in 't/t0021/rot13-filter.pl'.

Signed-off-by: Christian Couder <chriscool@xxxxxxxxxxxxx>
---
 perl/Git/Packet.pm      | 33 +++++++++++++++++++++++++++++++++
 t/t0021/rot13-filter.pl |  9 ++-------
 2 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/perl/Git/Packet.pm b/perl/Git/Packet.pm
index b0233caf37..4443b67724 100644
--- a/perl/Git/Packet.pm
+++ b/perl/Git/Packet.pm
@@ -20,6 +20,9 @@ our @EXPORT = qw(
 			packet_txt_write
 			packet_flush
 			packet_initialize
+			packet_read_capabilities
+			packet_write_capabilities
+			packet_read_and_check_capabilities
 		);
 our @EXPORT_OK = @EXPORT;
 
@@ -83,3 +86,33 @@ sub packet_initialize {
 	packet_txt_write( "version=" . $version );
 	packet_flush();
 }
+
+sub packet_read_capabilities {
+	my @cap;
+	while (1) {
+		my ( $res, $buf ) = packet_bin_read();
+		return ( $res, @cap ) if ( $res != 0 );
+		unless ( $buf =~ s/\n$// ) {
+			die "A non-binary line MUST be terminated by an LF.\n"
+			    . "Received: '$buf'";
+		}
+		die "bad capability buf: '$buf'" unless ( $buf =~ s/capability=// );
+		push @cap, $buf;
+	}
+}
+
+sub packet_read_and_check_capabilities {
+	my @local_caps = @_;
+	my @remote_res_caps = packet_read_capabilities();
+	my $res = shift @remote_res_caps;
+	my %remote_caps = map { $_ => 1 } @remote_res_caps;
+	foreach (@local_caps) {
+	    die "'$_' capability not available" unless (exists($remote_caps{$_}));
+	}
+	return $res;
+}
+
+sub packet_write_capabilities {
+	packet_txt_write( "capability=" . $_ ) foreach (@_);
+	packet_flush();
+}
diff --git a/t/t0021/rot13-filter.pl b/t/t0021/rot13-filter.pl
index 5b05518640..bbfd52619d 100644
--- a/t/t0021/rot13-filter.pl
+++ b/t/t0021/rot13-filter.pl
@@ -42,14 +42,9 @@ $debug->flush();
 
 packet_initialize("git-filter", 2);
 
-( packet_txt_read() eq ( 0, "capability=clean" ) )  || die "bad capability";
-( packet_txt_read() eq ( 0, "capability=smudge" ) ) || die "bad capability";
-( packet_bin_read() eq ( 1, "" ) )                  || die "bad capability end";
+packet_read_and_check_capabilities("clean", "smudge");
+packet_write_capabilities(@capabilities);
 
-foreach (@capabilities) {
-	packet_txt_write( "capability=" . $_ );
-}
-packet_flush();
 print $debug "init handshake complete\n";
 $debug->flush();
 
-- 
2.13.1.565.gbfcd7a9048