Add lease request and release protocol

Explicitly request / release leases instead of implicitly
by opening and closing the connection.  This will allow the
lease manager to take different action when a client
shuts down gracefully vs when it crashes, holding a lease.

Bug-AGL: SPEC-3862

Signed-off-by: Damian Hobson-Garcia <dhobsong@igel.co.jp>
Change-Id: Ibc68bee855ce18e56eb6f57e5ad1743248320013

2 files changed, 41 insertions, 7 deletions

diff --git a/libdlmclient/dlmclient.c b/libdlmclient/dlmclient.c
index 32493d3..03c08a8 100644
--- a/libdlmclient/dlmclient.c
+++ b/libdlmclient/dlmclient.c
@@ -14,6 +14,8 @@
  */
 
 #include "dlmclient.h"
+
+#include "dlm-protocol.h"
 #include "log.h"
 #include "socket-path.h"
 
@@ -46,7 +48,7 @@ static bool lease_connect(struct dlm_lease *lease, const char *name)
 	if (!sockaddr_set_lease_server_path(&sa, name))
 		return false;
 
-	int dlm_server_sock = socket(AF_UNIX, SOCK_STREAM, 0);
+	int dlm_server_sock = socket(AF_UNIX, SOCK_SEQPACKET, 0);
 	if (dlm_server_sock < 0) {
 		DEBUG_LOG("Socket creation failed: %s\n", strerror(errno));
 		return false;
@@ -65,6 +67,19 @@ static bool lease_connect(struct dlm_lease *lease, const char *name)
 	return true;
 }
 
+static bool lease_send_request(struct dlm_lease *lease, enum dlm_opcode opcode)
+{
+	struct dlm_client_request request = {
+	    .opcode = opcode,
+	};
+
+	if (!send_dlm_client_request(lease->dlm_server_sock, &request)) {
+		DEBUG_LOG("Socket data send error: %s\n", strerror(errno));
+		return false;
+	}
+	return true;
+}
+
 static bool lease_recv_fd(struct dlm_lease *lease)
 {
 	char ctrl_buf[CMSG_SPACE(sizeof(int))] = {0};
@@ -131,6 +146,7 @@ static bool lease_recv_fd(struct dlm_lease *lease)
 
 struct dlm_lease *dlm_get_lease(const char *name)
 {
+	int saved_errno;
 	struct dlm_lease *lease = calloc(1, sizeof(struct dlm_lease));
 	if (!lease) {
 		DEBUG_LOG("can't allocate memory : %s\n", strerror(errno));
@@ -142,13 +158,19 @@ struct dlm_lease *dlm_get_lease(const char *name)
 		return NULL;
 	}
 
-	if (!lease_recv_fd(lease)) {
-		close(lease->dlm_server_sock);
-		free(lease);
-		return NULL;
-	}
+	if (!lease_send_request(lease, DLM_GET_LEASE))
+		goto err;
+
+	if (!lease_recv_fd(lease))
+		goto err;
 
 	return lease;
+
+err:
+	saved_errno = errno;
+	dlm_release_lease(lease);
+	errno = saved_errno;
+	return NULL;
 }
 
 void dlm_release_lease(struct dlm_lease *lease)
@@ -156,6 +178,7 @@ void dlm_release_lease(struct dlm_lease *lease)
 	if (!lease)
 		return;
 
+	lease_send_request(lease, DLM_RELEASE_LEASE);
 	close(lease->lease_fd);
 	close(lease->dlm_server_sock);
 	free(lease);
diff --git a/libdlmclient/test/test-socket-server.c b/libdlmclient/test/test-socket-server.c
index 281aaf7..6aaa4e4 100644
--- a/libdlmclient/test/test-socket-server.c
+++ b/libdlmclient/test/test-socket-server.c
@@ -25,6 +25,7 @@
 #include <sys/un.h>
 #include <unistd.h>
 
+#include "dlm-protocol.h"
 #include "socket-path.h"
 #include "test-helpers.h"
 
@@ -56,6 +57,13 @@ static void send_fd_list_over_socket(int socket, int nfds, int *fds)
 	free(buf);
 }
 
+static void expect_client_command(int socket, enum dlm_opcode opcode)
+{
+	struct dlm_client_request req;
+	ck_assert_int_eq(receive_dlm_client_request(socket, &req), true);
+	ck_assert_int_eq(req.opcode, opcode);
+}
+
 struct server_state {
 	pthread_t tid;
 	pthread_mutex_t lock;
@@ -77,7 +85,7 @@ static void *test_server_thread(void *arg)
 	ck_assert_int_eq(
 	    sockaddr_set_lease_server_path(&address, config->lease_name), true);
 
-	int server = socket(PF_UNIX, SOCK_STREAM, 0);
+	int server = socket(PF_UNIX, SOCK_SEQPACKET, 0);
 	ck_assert_int_ge(server, 0);
 
 	unlink(address.sun_path);
@@ -102,6 +110,8 @@ static void *test_server_thread(void *arg)
 		return NULL;
 	}
 
+	expect_client_command(client, DLM_GET_LEASE);
+
 	if (config->send_no_data)
 		goto done;
 
@@ -120,6 +130,7 @@ static void *test_server_thread(void *arg)
 		config->fds[i] = get_dummy_fd();
 
 	send_fd_list_over_socket(client, config->nfds, config->fds);
+	expect_client_command(client, DLM_RELEASE_LEASE);
 done:
 	close(client);
 	close(server);