[PATCH v4 10/35] protocol: introduce enum protocol_version value protocol_v2

[Brandon Williams <bmwill@google.com>]

Introduce protocol_v2, a new value for 'enum protocol_version'.
Subsequent patches will fill in the implementation of protocol_v2.

Signed-off-by: Brandon Williams <bmwill@google.com>
---
 builtin/fetch-pack.c   | 2 ++
 builtin/receive-pack.c | 6 ++++++
 builtin/send-pack.c    | 3 +++
 builtin/upload-pack.c  | 7 +++++++
 connect.c              | 3 +++
 protocol.c             | 2 ++
 protocol.h             | 1 +
 remote-curl.c          | 3 +++
 transport.c            | 9 +++++++++
 9 files changed, 36 insertions(+)

diff --git a/builtin/fetch-pack.c b/builtin/fetch-pack.c
index 85d4faf76..b2374ddbb 100644
--- a/builtin/fetch-pack.c
+++ b/builtin/fetch-pack.c
@@ -201,6 +201,8 @@ int cmd_fetch_pack(int argc, const char **argv, const char *prefix)
 			   PACKET_READ_GENTLE_ON_EOF);
 
 	switch (discover_version(&reader)) {
+	case protocol_v2:
+		die("support for protocol v2 not implemented yet");
 	case protocol_v1:
 	case protocol_v0:
 		get_remote_heads(&reader, &ref, 0, NULL, &shallow);
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index b7ce7c7f5..3656e94fd 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -1963,6 +1963,12 @@ int cmd_receive_pack(int argc, const char **argv, const char *prefix)
 		unpack_limit = receive_unpack_limit;
 
 	switch (determine_protocol_version_server()) {
+	case protocol_v2:
+		/*
+		 * push support for protocol v2 has not been implemented yet,
+		 * so ignore the request to use v2 and fallback to using v0.
+		 */
+		break;
 	case protocol_v1:
 		/*
 		 * v1 is just the original protocol with a version string,
diff --git a/builtin/send-pack.c b/builtin/send-pack.c
index 83cb125a6..b5427f75e 100644
--- a/builtin/send-pack.c
+++ b/builtin/send-pack.c
@@ -263,6 +263,9 @@ int cmd_send_pack(int argc, const char **argv, const char *prefix)
 			   PACKET_READ_GENTLE_ON_EOF);
 
 	switch (discover_version(&reader)) {
+	case protocol_v2:
+		die("support for protocol v2 not implemented yet");
+		break;
 	case protocol_v1:
 	case protocol_v0:
 		get_remote_heads(&reader, &remote_refs, REF_NORMAL,
diff --git a/builtin/upload-pack.c b/builtin/upload-pack.c
index 2cb5cb35b..8d53e9794 100644
--- a/builtin/upload-pack.c
+++ b/builtin/upload-pack.c
@@ -47,6 +47,13 @@ int cmd_upload_pack(int argc, const char **argv, const char *prefix)
 		die("'%s' does not appear to be a git repository", dir);
 
 	switch (determine_protocol_version_server()) {
+	case protocol_v2:
+		/*
+		 * fetch support for protocol v2 has not been implemented yet,
+		 * so ignore the request to use v2 and fallback to using v0.
+		 */
+		upload_pack(&opts);
+		break;
 	case protocol_v1:
 		/*
 		 * v1 is just the original protocol with a version string,
diff --git a/connect.c b/connect.c
index 0b111e62d..4b89b984c 100644
--- a/connect.c
+++ b/connect.c
@@ -83,6 +83,9 @@ enum protocol_version discover_version(struct packet_reader *reader)
 	}
 
 	switch (version) {
+	case protocol_v2:
+		die("support for protocol v2 not implemented yet");
+		break;
 	case protocol_v1:
 		/* Read the peeked version line */
 		packet_reader_read(reader);
diff --git a/protocol.c b/protocol.c
index 43012b7eb..5e636785d 100644
--- a/protocol.c
+++ b/protocol.c
@@ -8,6 +8,8 @@ static enum protocol_version parse_protocol_version(const char *value)
 		return protocol_v0;
 	else if (!strcmp(value, "1"))
 		return protocol_v1;
+	else if (!strcmp(value, "2"))
+		return protocol_v2;
 	else
 		return protocol_unknown_version;
 }
diff --git a/protocol.h b/protocol.h
index 1b2bc94a8..2ad35e433 100644
--- a/protocol.h
+++ b/protocol.h
@@ -5,6 +5,7 @@ enum protocol_version {
 	protocol_unknown_version = -1,
 	protocol_v0 = 0,
 	protocol_v1 = 1,
+	protocol_v2 = 2,
 };
 
 /*
diff --git a/remote-curl.c b/remote-curl.c
index 9f6d07683..dae8a4a48 100644
--- a/remote-curl.c
+++ b/remote-curl.c
@@ -185,6 +185,9 @@ static struct ref *parse_git_refs(struct discovery *heads, int for_push)
 			   PACKET_READ_GENTLE_ON_EOF);
 
 	switch (discover_version(&reader)) {
+	case protocol_v2:
+		die("support for protocol v2 not implemented yet");
+		break;
 	case protocol_v1:
 	case protocol_v0:
 		get_remote_heads(&reader, &list, for_push ? REF_NORMAL : 0,
diff --git a/transport.c b/transport.c
index 2378dcb38..83d9dd1df 100644
--- a/transport.c
+++ b/transport.c
@@ -203,6 +203,9 @@ static struct ref *get_refs_via_connect(struct transport *transport, int for_pus
 
 	data->version = discover_version(&reader);
 	switch (data->version) {
+	case protocol_v2:
+		die("support for protocol v2 not implemented yet");
+		break;
 	case protocol_v1:
 	case protocol_v0:
 		get_remote_heads(&reader, &refs,
@@ -250,6 +253,9 @@ static int fetch_refs_via_pack(struct transport *transport,
 		refs_tmp = get_refs_via_connect(transport, 0);
 
 	switch (data->version) {
+	case protocol_v2:
+		die("support for protocol v2 not implemented yet");
+		break;
 	case protocol_v1:
 	case protocol_v0:
 		refs = fetch_pack(&args, data->fd, data->conn,
@@ -585,6 +591,9 @@ static int git_transport_push(struct transport *transport, struct ref *remote_re
 		args.push_cert = SEND_PACK_PUSH_CERT_NEVER;
 
 	switch (data->version) {
+	case protocol_v2:
+		die("support for protocol v2 not implemented yet");
+		break;
 	case protocol_v1:
 	case protocol_v0:
 		ret = send_pack(&args, data->fd, data->conn, remote_refs,
-- 
2.16.2.395.g2e18187dfd-goog