[WIP 09/15] transport: store protocol version

[Brandon Williams]

Once protocol_v2 is introduced requesting a fetch or a push will need to
be handled differently depending on the protocol version.  Store the
protocol version the serving is speaking in 'struct git_transport_data'
and use it to determine what to do in the case of a fetch or a push.

Signed-off-by: Brandon Williams <bmw...@google.com>
---
 transport.c | 35 ++++++++++++++++++++++++++---------
 1 file changed, 26 insertions(+), 9 deletions(-)

diff --git a/transport.c b/transport.c
index 28b744ec2..4160c4167 100644
--- a/transport.c
+++ b/transport.c
@@ -118,6 +118,7 @@ struct git_transport_data {
        struct child_process *conn;
        int fd[2];
        unsigned got_remote_heads : 1;
+       enum protocol_version version;
        struct oid_array extra_have;
        struct oid_array shallow;
 };
@@ -198,7 +199,8 @@ static struct ref *get_refs_via_connect(struct transport 
*transport, int for_pus
 
        packet_reader_init(&reader, data->fd[0], NULL, 0);
 
-       switch (discover_version(&reader)) {
+       data->version = discover_version(&reader);
+       switch (data->version) {
        case protocol_v1:
        case protocol_v0:
                get_remote_heads(&reader, &refs,
@@ -219,7 +221,7 @@ static int fetch_refs_via_pack(struct transport *transport,
 {
        int ret = 0;
        struct git_transport_data *data = transport->data;
-       struct ref *refs;
+       struct ref *refs = NULL;
        char *dest = xstrdup(transport->url);
        struct fetch_pack_args args;
        struct ref *refs_tmp = NULL;
@@ -245,10 +247,18 @@ static int fetch_refs_via_pack(struct transport 
*transport,
        if (!data->got_remote_heads)
                refs_tmp = get_refs_via_connect(transport, 0);
 
-       refs = fetch_pack(&args, data->fd, data->conn,
-                         refs_tmp ? refs_tmp : transport->remote_refs,
-                         dest, to_fetch, nr_heads, &data->shallow,
-                         &transport->pack_lockfile);
+       switch (data->version) {
+       case protocol_v1:
+       case protocol_v0:
+               refs = fetch_pack(&args, data->fd, data->conn,
+                                 refs_tmp ? refs_tmp : transport->remote_refs,
+                                 dest, to_fetch, nr_heads, &data->shallow,
+                                 &transport->pack_lockfile);
+               break;
+       case protocol_unknown_version:
+               BUG("unknown protocol version");
+       }
+
        close(data->fd[0]);
        close(data->fd[1]);
        if (finish_connect(data->conn))
@@ -548,7 +558,7 @@ static int git_transport_push(struct transport *transport, 
struct ref *remote_re
 {
        struct git_transport_data *data = transport->data;
        struct send_pack_args args;
-       int ret;
+       int ret = 0;
 
        if (!data->got_remote_heads)
                get_refs_via_connect(transport, 1);
@@ -573,8 +583,15 @@ static int git_transport_push(struct transport *transport, 
struct ref *remote_re
        else
                args.push_cert = SEND_PACK_PUSH_CERT_NEVER;
 
-       ret = send_pack(&args, data->fd, data->conn, remote_refs,
-                       &data->extra_have);
+       switch (data->version) {
+       case protocol_v1:
+       case protocol_v0:
+               ret = send_pack(&args, data->fd, data->conn, remote_refs,
+                               &data->extra_have);
+               break;
+       case protocol_unknown_version:
+               BUG("unknown protocol version");
+       }
 
        close(data->fd[1]);
        close(data->fd[0]);
-- 
2.15.1.424.g9478a66081-goog