Git/Packet: clarify that packet_required_key_val_read allows EOF

The function calls itself "required", but it does not die when it
sees an unexpected EOF.

Let's rename it to "packet_key_val_read()".

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

perl/Git/Packet.pm

@@ -17,7 +17,7 @@ our @EXPORT = qw(
 			packet_compare_lists
 			packet_bin_read
 			packet_txt_read
-			packet_required_key_val_read
+			packet_key_val_read
 			packet_bin_write
 			packet_txt_write
 			packet_flush
@@ -83,7 +83,12 @@ sub packet_txt_read {
 	return ( $res, $buf );
 }
 
-sub packet_required_key_val_read {
+# Read a text packet, expecting that it is in the form "key=value" for
+# the given $key.  An EOF does not trigger any error and is reported
+# back to the caller (like packet_txt_read() does).  Die if the "key"
+# part of "key=value" does not match the given $key, or the value part
+# is empty.
+sub packet_key_val_read {
 	my ( $key ) = @_;
 	my ( $res, $buf ) = packet_txt_read();
 	unless ( $res == -1 or ( $buf =~ s/^$key=// and $buf ne '' ) ) {

t/t0021/rot13-filter.pl

@@ -70,7 +70,7 @@ print $debug "init handshake complete\n";
 $debug->flush();
 
 while (1) {
-	my ( $res, $command ) = packet_required_key_val_read("command");
+	my ( $res, $command ) = packet_key_val_read("command");
 	if ( $res == -1 ) {
 		print $debug "STOP\n";
 		exit();
@@ -106,7 +106,7 @@ while (1) {
 		packet_txt_write("status=success");
 		packet_flush();
 	} else {
-		my ( $res, $pathname ) = packet_required_key_val_read("pathname");
+		my ( $res, $pathname ) = packet_key_val_read("pathname");
 		if ( $res == -1 ) {
 			die "unexpected EOF while expecting pathname";
 		}