[PATCH 05/14] transport: add infrastructure to support a protocol version number

[Stefan Beller <sbeller@google.com>]

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 fetch-pack.h       |  1 +
 remote.c           |  2 ++
 remote.h           |  2 ++
 transport-helper.c |  1 +
 transport.c        | 20 ++++++++++++++++++--
 transport.h        |  8 ++++++++
 6 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/fetch-pack.h b/fetch-pack.h
index bb7fd76..3314362 100644
--- a/fetch-pack.h
+++ b/fetch-pack.h
@@ -8,6 +8,7 @@ struct sha1_array;
 
 struct fetch_pack_args {
 	const char *uploadpack;
+	int transport_version;
 	int unpacklimit;
 	int depth;
 	unsigned quiet:1;
diff --git a/remote.c b/remote.c
index 28fd676..760611d 100644
--- a/remote.c
+++ b/remote.c
@@ -9,6 +9,7 @@
 #include "string-list.h"
 #include "mergesort.h"
 #include "argv-array.h"
+#include "transport.h"
 
 enum map_direction { FROM_SRC, FROM_DST };
 
@@ -164,6 +165,7 @@ static struct remote *make_remote(const char *name, int len)
 		return ret;
 
 	ret = xcalloc(1, sizeof(struct remote));
+	ret->transport_version = DEFAULT_TRANSPORT_VERSION;
 	ret->prune = -1;  /* unspecified */
 	ALLOC_GROW(remotes, remotes_nr + 1, remotes_alloc);
 	remotes[remotes_nr++] = ret;
diff --git a/remote.h b/remote.h
index c21fd37..cdb25d0 100644
--- a/remote.h
+++ b/remote.h
@@ -51,6 +51,8 @@ struct remote {
 	const char *receivepack;
 	const char *uploadpack;
 
+	int transport_version;
+
 	/*
 	 * for curl remotes only
 	 */
diff --git a/transport-helper.c b/transport-helper.c
index b934183..3cb386f 100644
--- a/transport-helper.c
+++ b/transport-helper.c
@@ -248,6 +248,7 @@ static int disconnect_helper(struct transport *transport)
 }
 
 static const char *unsupported_options[] = {
+	TRANS_OPT_TRANSPORTVERSION,
 	TRANS_OPT_UPLOADPACK,
 	TRANS_OPT_RECEIVEPACK,
 	TRANS_OPT_THIN,
diff --git a/transport.c b/transport.c
index 095e61f..608b92c 100644
--- a/transport.c
+++ b/transport.c
@@ -151,6 +151,16 @@ static int set_git_option(struct git_transport_options *opts,
 				die("transport: invalid depth option '%s'", value);
 		}
 		return 0;
+	} else if (!strcmp(name, TRANS_OPT_TRANSPORTVERSION)) {
+		if (!value)
+			opts->transport_version = DEFAULT_TRANSPORT_VERSION;
+		else {
+			char *end;
+			opts->transport_version = strtol(value, &end, 0);
+			if (*end)
+				die("transport: invalid transport version option '%s'", value);
+		}
+		return 0;
 	}
 	return 1;
 }
@@ -203,6 +213,7 @@ static int fetch_refs_via_pack(struct transport *transport,
 
 	memset(&args, 0, sizeof(args));
 	args.uploadpack = data->options.uploadpack;
+	args.transport_version = data->options.transport_version;
 	args.keep_pack = data->options.keep;
 	args.lock_pack = 1;
 	args.use_thin_pack = data->options.thin;
@@ -694,6 +705,8 @@ struct transport *transport_get(struct remote *remote, const char *url)
 		ret->connect = connect_git;
 		ret->disconnect = disconnect_git;
 		ret->smart_options = &(data->options);
+		ret->smart_options->transport_version =
+			DEFAULT_TRANSPORT_VERSION;
 
 		data->conn = NULL;
 		data->got_remote_heads = 0;
@@ -706,12 +719,15 @@ struct transport *transport_get(struct remote *remote, const char *url)
 
 	if (ret->smart_options) {
 		ret->smart_options->thin = 1;
-		ret->smart_options->uploadpack = "git-upload-pack";
+		ret->smart_options->uploadpack = DEFAULT_TRANSPORT_UPLOAD_PACK;
 		if (remote->uploadpack)
 			ret->smart_options->uploadpack = remote->uploadpack;
-		ret->smart_options->receivepack = "git-receive-pack";
+		ret->smart_options->receivepack = DEFAULT_TRANSPORT_RECEIVE_PACK;
 		if (remote->receivepack)
 			ret->smart_options->receivepack = remote->receivepack;
+		if (remote->transport_version)
+			ret->smart_options->transport_version =
+				remote->transport_version;
 	}
 
 	return ret;
diff --git a/transport.h b/transport.h
index c681408..af90529 100644
--- a/transport.h
+++ b/transport.h
@@ -13,6 +13,7 @@ struct git_transport_options {
 	unsigned self_contained_and_connected : 1;
 	unsigned update_shallow : 1;
 	int depth;
+	int transport_version;
 	const char *uploadpack;
 	const char *receivepack;
 	struct push_cas_option *cas;
@@ -188,6 +189,13 @@ int transport_restrict_protocols(void);
 /* Send push certificates */
 #define TRANS_OPT_PUSH_CERT "pushcert"
 
+/* Use a new version of the git protocol */
+#define TRANS_OPT_TRANSPORTVERSION "transportversion"
+
+#define DEFAULT_TRANSPORT_VERSION 1
+#define DEFAULT_TRANSPORT_UPLOAD_PACK "git-upload-pack"
+#define DEFAULT_TRANSPORT_RECEIVE_PACK "git-receive-pack"
+
 /**
  * Returns 0 if the option was used, non-zero otherwise. Prints a
  * message to stderr if the option is not used.
-- 
2.8.0.32.g71f8beb.dirty