[PATCH 08/10] upload-pack, serve: log received client trace2 SID

[Josh Steadmon <steadmon@google.com>]

When upload-pack (protocol v0/v1) or a protocol v2 server receives a
trace2-sid capability from a client, log the received session ID via a
trace2 data event.

Signed-off-by: Josh Steadmon <steadmon@google.com>
---
 serve.c                               |  4 ++++
 t/t5705-trace2-sid-in-capabilities.sh | 19 +++++++++++++------
 upload-pack.c                         |  7 +++++++
 3 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/serve.c b/serve.c
index 6ad73d69ab..6a4f0c64a9 100644
--- a/serve.c
+++ b/serve.c
@@ -202,6 +202,7 @@ static int process_request(void)
 	struct packet_reader reader;
 	struct strvec keys = STRVEC_INIT;
 	struct protocol_capability *command = NULL;
+	const char *client_sid;
 
 	packet_reader_init(&reader, 0, NULL, 0,
 			   PACKET_READ_CHOMP_NEWLINE |
@@ -265,6 +266,9 @@ static int process_request(void)
 
 	check_algorithm(the_repository, &keys);
 
+	if (has_capability(&keys, "trace2-sid", &client_sid))
+		trace2_data_string("trace2", NULL, "client-sid", client_sid);
+
 	command->command(the_repository, &keys, &reader);
 
 	strvec_clear(&keys);
diff --git a/t/t5705-trace2-sid-in-capabilities.sh b/t/t5705-trace2-sid-in-capabilities.sh
index 0870e78f7c..3fad9462d3 100755
--- a/t/t5705-trace2-sid-in-capabilities.sh
+++ b/t/t5705-trace2-sid-in-capabilities.sh
@@ -17,11 +17,14 @@ test_expect_success 'setup repos for trace2 SID capability tests' '
 for PROTO in 0 1 2
 do
 	test_expect_success "trace2 session IDs not advertised by default (fetch v${PROTO})" '
-		test_when_finished "rm -rf local tr2-client-events" &&
+		test_when_finished "rm -rf local tr2-client-events tr2-server-events" &&
 		cp -r "$LOCAL_PRISTINE" local &&
 		GIT_TRACE2_EVENT="$(pwd)/tr2-client-events" \
-		git -c protocol.version=$PROTO -C local fetch origin &&
-		test -z "$(grep \"key\":\"server-sid\" tr2-client-events)"
+		git -c protocol.version=$PROTO -C local fetch \
+			--upload-pack "GIT_TRACE2_EVENT=\"$(pwd)/tr2-server-events\" git-upload-pack" \
+			origin &&
+		test -z "$(grep \"key\":\"server-sid\" tr2-client-events)" &&
+		test -z "$(grep \"key\":\"client-sid\" tr2-server-events)"
 	'
 
 	test_expect_success "trace2 session IDs not advertised by default (push v${PROTO})" '
@@ -43,11 +46,15 @@ test_expect_success 'enable SID advertisement' '
 for PROTO in 0 1 2
 do
 	test_expect_success "trace2 session IDs advertised (fetch v${PROTO})" '
-		test_when_finished "rm -rf local tr2-client-events" &&
+		test_when_finished "rm -rf local tr2-client-events tr2-server-events" &&
 		cp -r "$LOCAL_PRISTINE" local &&
+		git -C local config trace2.advertiseSID true &&
 		GIT_TRACE2_EVENT="$(pwd)/tr2-client-events" \
-		git -c protocol.version=$PROTO -C local fetch origin &&
-		grep \"key\":\"server-sid\" tr2-client-events
+		git -c protocol.version=$PROTO -C local fetch \
+			--upload-pack "GIT_TRACE2_EVENT=\"$(pwd)/tr2-server-events\" git-upload-pack" \
+			origin &&
+		grep \"key\":\"server-sid\" tr2-client-events &&
+		grep \"key\":\"client-sid\" tr2-server-events
 	'
 
 	test_expect_success "trace2 session IDs advertised (push v${PROTO})" '
diff --git a/upload-pack.c b/upload-pack.c
index 862656010c..4238e06510 100644
--- a/upload-pack.c
+++ b/upload-pack.c
@@ -1059,6 +1059,7 @@ static void receive_needs(struct upload_pack_data *data,
 		const char *features;
 		struct object_id oid_buf;
 		const char *arg;
+		int feature_len;
 
 		reset_timeout(data->timeout);
 		if (packet_reader_read(reader) != PACKET_READ_NORMAL)
@@ -1110,6 +1111,12 @@ static void receive_needs(struct upload_pack_data *data,
 		if (data->allow_filter &&
 		    parse_feature_request(features, "filter"))
 			data->filter_capability_requested = 1;
+		if ((arg = parse_feature_value(features, "trace2-sid", &feature_len, 0)))
+		{
+			char *client_sid = xstrndup(arg, feature_len);
+			trace2_data_string("trace2", NULL, "client-sid", client_sid);
+			free(client_sid);
+		}
 
 		o = parse_object(the_repository, &oid_buf);
 		if (!o) {
-- 
2.29.1.341.ge80a0c044ae-goog