Hello Harald Welte, Jenkins Builder,
I'd like you to reexamine a change. Please visit
https://gerrit.osmocom.org/5881
to look at the new patch set (#12).
client: add an optional FSM interface
the client API is not very intuitive and requires a lot of extra
care when it is used from an osmo-fsm.
- Add an FSM that permits comfortable handling of an MGCP
connection.
Change-Id: I887ce0c15a831dffeb6251a975337b83942af566
---
M include/Makefile.am
A include/osmocom/mgcp_client/mgcp_client_fsm.h
M src/libosmo-mgcp-client/Makefile.am
A src/libosmo-mgcp-client/mgcp_client_fsm.c
4 files changed, 693 insertions(+), 0 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/osmo-mgw refs/changes/81/5881/12
diff --git a/include/Makefile.am b/include/Makefile.am
index b52e5ea..e8fc211 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -7,6 +7,7 @@
osmocom/legacy_mgcp/mgcp_internal.h \
osmocom/legacy_mgcp/osmux.h \
osmocom/mgcp_client/mgcp_client.h \
+ osmocom/mgcp_client/mgcp_client_fsm.h \
osmocom/mgcp_client/mgcp_common.h \
osmocom/mgcp/mgcp.h \
osmocom/mgcp/mgcp_common.h \
diff --git a/include/osmocom/mgcp_client/mgcp_client_fsm.h
b/include/osmocom/mgcp_client/mgcp_client_fsm.h
new file mode 100644
index 0000000..7d06178
--- /dev/null
+++ b/include/osmocom/mgcp_client/mgcp_client_fsm.h
@@ -0,0 +1,33 @@
+#pragma once
+
+#include <osmocom/mgcp_client/mgcp_common.h>
+#include <osmocom/mgcp_client/mgcp_client.h>
+#include <osmocom/gsm/protocol/gsm_04_08.h>
+
+/*! This struct organizes the connection infromation one connection side
+ * (either remote or local). It is used to pass parameters (local) to the FSM
+ * and get responses (remote) from the FSM as pointer attached to the FSM
+ * event.
+ *
+ * When modifiying a connection, the endpoint and call_id members may be left
+ * unpopulated. The call_id field is ignored in this case. If an endpoint
+ * identifier is supplied it is checked against the internal state to make
+ * sure it is correct. */
+struct mgcp_conn_peer {
+ /*!< RTP connection IP-Address (optional, string e.g. "127.0.0.1") */
+ char addr[INET_ADDRSTRLEN];
+
+ /*!< RTP connection IP-Port (optional) */
+ uint16_t port;
+
+ /*!< RTP endpoint */
+ char endpoint[MGCP_ENDPOINT_MAXLEN];
+
+ /*!< CALL ID (unique per connection) */
+ unsigned int call_id;
+};
+
+struct osmo_fsm_inst *mgcp_conn_create(struct mgcp_client *mgcp, struct
osmo_fsm_inst *parent_fi, uint32_t parent_term_evt,
+ uint32_t parent_evt, struct
mgcp_conn_peer *conn_peer);
+int mgcp_conn_modify(struct osmo_fsm_inst *fi, uint32_t parent_evt, struct
mgcp_conn_peer *conn_peer);
+void mgcp_conn_delete(struct osmo_fsm_inst *fi);
diff --git a/src/libosmo-mgcp-client/Makefile.am
b/src/libosmo-mgcp-client/Makefile.am
index 1e4e764..a3a920b 100644
--- a/src/libosmo-mgcp-client/Makefile.am
+++ b/src/libosmo-mgcp-client/Makefile.am
@@ -29,6 +29,7 @@
libosmo_mgcp_client_la_SOURCES = \
mgcp_client.c \
mgcp_client_vty.c \
+ mgcp_client_fsm.c \
$(NULL)
libosmo_mgcp_client_la_LDFLAGS = $(AM_LDFLAGS) -version-info
$(MGCP_CLIENT_LIBVERSION)
diff --git a/src/libosmo-mgcp-client/mgcp_client_fsm.c
b/src/libosmo-mgcp-client/mgcp_client_fsm.c
new file mode 100644
index 0000000..a2565e7
--- /dev/null
+++ b/src/libosmo-mgcp-client/mgcp_client_fsm.c
@@ -0,0 +1,658 @@
+/* (C) 2018 by sysmocom s.f.m.c. GmbH <i...@sysmocom.de>
+ * All Rights Reserved
+ *
+ * Author: Philipp Maier
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <osmocom/mgcp_client/mgcp_client.h>
+#include <osmocom/mgcp_client/mgcp_client_fsm.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/fsm.h>
+#include <osmocom/core/byteswap.h>
+#include <arpa/inet.h>
+#include <osmocom/core/logging.h>
+
+/* Context information, this is attached to the priv pointer of the FSM and
+ * is also handed back when dispatcheing events to the parent FSM. This is
+ * purly intened and not meant to be accessible for the API user */
+struct mgcp_ctx {
+ /* MGCP client instance that is used to interact with the MGW */
+ struct mgcp_client *mgcp;
+
+ /* The ID of the last pending transaction. This is used internally
+ * to cancel the transaction in case of an error */
+ mgcp_trans_id_t mgw_pending_trans;
+
+ /* Flag to mark that there is a pending transaction */
+ bool mgw_trans_pending;
+
+ /* Connection ID which has been assigned by he MGW */
+ char conn_id[MGCP_CONN_ID_LENGTH];
+
+ /* Local RTP connection info, the MGW will send outgoing traffic to the
+ * ip/port specified here. The Address does not have to be choosen right
+ * on the creation of a connection. It can always be modified later by
+ * the user. */
+ struct mgcp_conn_peer conn_peer_local;
+
+ /* Remote RTP connection info, the ip/port specified here is the address
+ * where the MGW expects the RTP data to be sent. This address is
+ * defined by soly by the MGW and can not be influenced by the user. */
+ struct mgcp_conn_peer conn_peer_remote;
+
+ /* The terminate flag is a way to handle cornercase sitations that
+ * might occur when the user runs into an error situation and sends
+ * a DLCX command while the FSM is waiting for a response. In this
+ * case the DLCX command is not executed immediately. Instead the
+ * terminate flag is set. When the response to from the previous
+ * operation is received, we know that there is a DLCX event is
+ * pending. The FSM then generates the EV_DLCX by itsself before
+ * it enters ST_READY to cause the immediate execution of the
+ * DLCX procedure. (If normal operations are executed too fast,
+ * the API functions will return an error. In general, the user
+ * should synchronize using the callback events) */
+ bool terminate;
+
+ /* Event that is sent when the current operation is completed (except
+ * for DLCX, there the specified parent_term_evt is sent instead) */
+ uint32_t parent_evt;
+};
+
+#define S(x) (1 << (x))
+
+#define MGCP_MGW_TIMEOUT 4 /* in seconds */
+#define MGCP_MGW_TIMEOUT_TIMER_NR 1
+
+enum fsm_bsc_mgcp_states {
+ ST_CRCX,
+ ST_CRCX_RESP,
+ ST_READY,
+ ST_MDCX_RESP,
+ ST_DLCX_RESP,
+};
+
+enum bsc_mgcp_fsm_evt {
+ EV_CRCX,
+ EV_CRCX_RESP,
+ EV_MDCX,
+ EV_MDCX_RESP,
+ EV_DLCX,
+ EV_DLCX_RESP,
+};
+
+static struct msgb *make_crcx_msg_bind(struct mgcp_ctx *mgcp_ctx)
+{
+ struct mgcp_msg mgcp_msg;
+
+ mgcp_msg = (struct mgcp_msg) {
+ .verb = MGCP_VERB_CRCX,
+ .presence = (MGCP_MSG_PRESENCE_ENDPOINT |
MGCP_MSG_PRESENCE_CALL_ID | MGCP_MSG_PRESENCE_CONN_MODE),
+ .call_id = mgcp_ctx->conn_peer_local.call_id,
+ .conn_mode = MGCP_CONN_LOOPBACK,
+ };
+ osmo_strlcpy(mgcp_msg.endpoint, mgcp_ctx->conn_peer_local.endpoint,
MGCP_ENDPOINT_MAXLEN);
+
+ return mgcp_msg_gen(mgcp_ctx->mgcp, &mgcp_msg);
+}
+
+static struct msgb *make_crcx_msg_bind_connect(struct mgcp_ctx *mgcp_ctx)
+{
+ struct mgcp_msg mgcp_msg;
+
+ mgcp_msg = (struct mgcp_msg) {
+ .verb = MGCP_VERB_CRCX,.presence = (MGCP_MSG_PRESENCE_ENDPOINT
| MGCP_MSG_PRESENCE_CALL_ID |
+ MGCP_MSG_PRESENCE_CONN_MODE
| MGCP_MSG_PRESENCE_AUDIO_IP |
+
MGCP_MSG_PRESENCE_AUDIO_PORT),
+ .call_id = mgcp_ctx->conn_peer_local.call_id,
+ .conn_mode = MGCP_CONN_RECV_SEND,
+ .audio_ip = mgcp_ctx->conn_peer_local.addr,
+ .audio_port = mgcp_ctx->conn_peer_local.port,
+ };
+ osmo_strlcpy(mgcp_msg.endpoint, mgcp_ctx->conn_peer_local.endpoint,
MGCP_ENDPOINT_MAXLEN);
+
+ return mgcp_msg_gen(mgcp_ctx->mgcp, &mgcp_msg);
+}
+
+static struct msgb *make_mdcx_msg(struct mgcp_ctx *mgcp_ctx)
+{
+ struct mgcp_msg mgcp_msg;
+
+ mgcp_msg = (struct mgcp_msg) {
+ .verb = MGCP_VERB_MDCX,
+ .presence = (MGCP_MSG_PRESENCE_ENDPOINT |
MGCP_MSG_PRESENCE_CALL_ID | MGCP_MSG_PRESENCE_CONN_ID |
+ MGCP_MSG_PRESENCE_CONN_MODE |
MGCP_MSG_PRESENCE_AUDIO_IP | MGCP_MSG_PRESENCE_AUDIO_PORT),
+ .call_id = mgcp_ctx->conn_peer_remote.call_id,
+ .conn_id = mgcp_ctx->conn_id,
+ .conn_mode = MGCP_CONN_RECV_SEND,
+ .audio_ip = mgcp_ctx->conn_peer_local.addr,
+ .audio_port = mgcp_ctx->conn_peer_local.port,
+ };
+ osmo_strlcpy(mgcp_msg.endpoint, mgcp_ctx->conn_peer_remote.endpoint,
MGCP_ENDPOINT_MAXLEN);
+
+ /* Note: We take the endpoint and the call_id from the remote
+ * connection info, because we can be confident that the
+ * information there is valid. For the local info, we explicitly
+ * allow endpoint and call_id to be optional */
+ return mgcp_msg_gen(mgcp_ctx->mgcp, &mgcp_msg);
+}
+
+struct msgb *make_dlcx_msg(struct mgcp_ctx *mgcp_ctx)
+{
+ struct mgcp_msg mgcp_msg;
+
+ mgcp_msg = (struct mgcp_msg) {
+ .verb = MGCP_VERB_DLCX,
+ .presence = (MGCP_MSG_PRESENCE_ENDPOINT |
MGCP_MSG_PRESENCE_CALL_ID | MGCP_MSG_PRESENCE_CONN_ID),
+ .call_id = mgcp_ctx->conn_peer_remote.call_id,
+ .conn_id = mgcp_ctx->conn_id,
+ };
+ osmo_strlcpy(mgcp_msg.endpoint, mgcp_ctx->conn_peer_remote.endpoint,
MGCP_ENDPOINT_MAXLEN);
+
+ return mgcp_msg_gen(mgcp_ctx->mgcp, &mgcp_msg);
+}
+
+static void mgw_crcx_resp_cb(struct mgcp_response *r, void *priv);
+
+static void fsm_crcx_cb(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+ struct mgcp_ctx *mgcp_ctx = data;
+ struct mgcp_client *mgcp;
+ struct msgb *msg;
+ int rc;
+
+ OSMO_ASSERT(mgcp_ctx);
+ mgcp = mgcp_ctx->mgcp;
+ OSMO_ASSERT(mgcp);
+
+ switch (event) {
+ case EV_CRCX:
+ LOGPFSML(fi, LOGL_DEBUG, "MGW/CRCX: creating connection on MGW
endpoint:%s...\n",
+ mgcp_ctx->conn_peer_local.endpoint);
+
+ if (mgcp_ctx->conn_peer_local.port)
+ msg = make_crcx_msg_bind_connect(mgcp_ctx);
+ else
+ msg = make_crcx_msg_bind(mgcp_ctx);
+ OSMO_ASSERT(msg);
+
+ mgcp_ctx->mgw_pending_trans = mgcp_msg_trans_id(msg);
+ mgcp_ctx->mgw_trans_pending = true;
+ rc = mgcp_client_tx(mgcp, msg, mgw_crcx_resp_cb, fi);
+ if (rc < 0) {
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+ return;
+ }
+
+ osmo_fsm_inst_state_chg(fi, ST_CRCX_RESP, MGCP_MGW_TIMEOUT,
MGCP_MGW_TIMEOUT_TIMER_NR);
+ break;
+ default:
+ OSMO_ASSERT(false);
+ break;
+ }
+}
+
+static void mgw_crcx_resp_cb(struct mgcp_response *r, void *priv)
+{
+ struct osmo_fsm_inst *fi = priv;
+ struct mgcp_ctx *mgcp_ctx;
+ int rc;
+
+ OSMO_ASSERT(fi);
+ mgcp_ctx = fi->priv;
+ OSMO_ASSERT(mgcp_ctx);
+
+ mgcp_ctx->mgw_trans_pending = false;
+
+ if (r->head.response_code != 200) {
+ LOGPFSML(fi, LOGL_ERROR,
+ "MGW/CRCX: response yields error: %d %s\n",
r->head.response_code, r->head.comment);
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+ return;
+ }
+
+ osmo_strlcpy(mgcp_ctx->conn_id, r->head.conn_id,
sizeof(mgcp_ctx->conn_id));
+ LOGPFSML(fi, LOGL_DEBUG, "MGW/CRCX: MGW responded with CI: %s\n",
mgcp_ctx->conn_id);
+
+ rc = mgcp_response_parse_params(r);
+ if (rc) {
+ LOGPFSML(fi, LOGL_ERROR, "MGW/CRCX: Cannot parse CRCX
response\n");
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+ return;
+ }
+ LOGPFSML(fi, LOGL_DEBUG, "MGW/CRCX: MGW responded with address
%s:%u\n", r->audio_ip, r->audio_port);
+
+ osmo_strlcpy(mgcp_ctx->conn_peer_remote.addr, r->audio_ip,
sizeof(mgcp_ctx->conn_peer_remote.addr));
+ mgcp_ctx->conn_peer_remote.port = r->audio_port;
+
+ if (strlen(r->head.endpoint) > 0) {
+ /* If we get an endpoint identifier back from the MGW, take it
*/
+ osmo_strlcpy(mgcp_ctx->conn_peer_remote.endpoint,
r->head.endpoint,
+ sizeof(mgcp_ctx->conn_peer_remote.endpoint));
+ } else if (strstr(mgcp_ctx->conn_peer_local.endpoint, "*") == NULL) {
+ /* If we do not get an endpoint identifier back and the
+ * identifier we used to create the connection is not a
+ * wildcarded one, we take the local endpoint identifier
+ * instead */
+ osmo_strlcpy(mgcp_ctx->conn_peer_remote.endpoint,
mgcp_ctx->conn_peer_local.endpoint,
+ sizeof(mgcp_ctx->conn_peer_local.endpoint));
+ } else {
+ LOGPFSML(fi, LOGL_ERROR, "MGW/CRCX: CRCX yielded not suitable
endpoint identifier\n");
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+ return;
+ }
+
+ mgcp_ctx->conn_peer_remote.call_id = mgcp_ctx->conn_peer_local.call_id;
+
+ osmo_fsm_inst_dispatch(fi, EV_CRCX_RESP, mgcp_ctx);
+}
+
+static void fsm_crcx_resp_cb(struct osmo_fsm_inst *fi, uint32_t event, void
*data)
+{
+ struct mgcp_ctx *mgcp_ctx = data;
+ OSMO_ASSERT(mgcp_ctx);
+
+ switch (event) {
+ case EV_CRCX_RESP:
+ osmo_fsm_inst_state_chg(fi, ST_READY, 0, 0);
+ if (mgcp_ctx->terminate) {
+ /* Trigger immediate DLCX if DLCX was requested while
the FSM was
+ * busy with the previous operation */
+ LOGPFSML(fi, LOGL_ERROR, "MGW/CRCX: FSM was busy while
DLCX was requested, executing now...\n");
+ osmo_fsm_inst_dispatch(fi, EV_DLCX, mgcp_ctx);
+ } else
+ osmo_fsm_inst_dispatch(fi->proc.parent,
mgcp_ctx->parent_evt, &mgcp_ctx->conn_peer_remote);
+ break;
+ default:
+ OSMO_ASSERT(false);
+ break;
+ }
+}
+
+static void mgw_mdcx_resp_cb(struct mgcp_response *r, void *priv);
+static void mgw_dlcx_resp_cb(struct mgcp_response *r, void *priv);
+
+static void fsm_ready_cb(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+ struct mgcp_ctx *mgcp_ctx = data;
+ struct msgb *msg;
+ struct mgcp_client *mgcp;
+ uint32_t new_state;
+ int rc;
+
+ OSMO_ASSERT(mgcp_ctx);
+ mgcp = mgcp_ctx->mgcp;
+ OSMO_ASSERT(mgcp);
+
+ switch (event) {
+ case EV_MDCX:
+ msg = make_mdcx_msg(mgcp_ctx);
+ OSMO_ASSERT(msg);
+ rc = mgcp_client_tx(mgcp, msg, mgw_mdcx_resp_cb, fi);
+ new_state = ST_MDCX_RESP;
+ break;
+ case EV_DLCX:
+ msg = make_dlcx_msg(mgcp_ctx);
+ OSMO_ASSERT(msg);
+ rc = mgcp_client_tx(mgcp, msg, mgw_dlcx_resp_cb, fi);
+ new_state = ST_DLCX_RESP;
+ break;
+ default:
+ OSMO_ASSERT(false);
+ break;
+ }
+
+ mgcp_ctx->mgw_pending_trans = mgcp_msg_trans_id(msg);
+ mgcp_ctx->mgw_trans_pending = true;
+
+ if (rc < 0) {
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+ return;
+ }
+
+ osmo_fsm_inst_state_chg(fi, new_state, MGCP_MGW_TIMEOUT,
MGCP_MGW_TIMEOUT_TIMER_NR);
+}
+
+static void mgw_mdcx_resp_cb(struct mgcp_response *r, void *priv)
+{
+ struct osmo_fsm_inst *fi = priv;
+ struct mgcp_ctx *mgcp_ctx;
+ int rc;
+
+ OSMO_ASSERT(fi);
+ mgcp_ctx = fi->priv;
+ OSMO_ASSERT(mgcp_ctx);
+
+ mgcp_ctx->mgw_trans_pending = false;
+
+ if (r->head.response_code != 200) {
+ LOGPFSML(fi, LOGL_ERROR, "MGW/MDCX: response yields error: %d
%s\n", r->head.response_code,
+ r->head.comment);
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+ return;
+ }
+
+ rc = mgcp_response_parse_params(r);
+ if (rc) {
+ LOGPFSML(fi, LOGL_ERROR, "MGW/MDCX: Cannot parse MDCX
response\n");
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+ return;
+ }
+ LOGPFSML(fi, LOGL_DEBUG, "MGW/MDCX: MGW responded with address
%s:%u\n", r->audio_ip, r->audio_port);
+
+ osmo_strlcpy(mgcp_ctx->conn_peer_remote.addr, r->audio_ip,
sizeof(mgcp_ctx->conn_peer_remote.addr));
+ mgcp_ctx->conn_peer_remote.port = r->audio_port;
+
+ osmo_fsm_inst_dispatch(fi, EV_MDCX_RESP, mgcp_ctx);
+}
+
+static void fsm_mdcx_resp_cb(struct osmo_fsm_inst *fi, uint32_t event, void
*data)
+{
+ struct mgcp_ctx *mgcp_ctx = data;
+ OSMO_ASSERT(mgcp_ctx);
+
+ switch (event) {
+ case EV_MDCX_RESP:
+ osmo_fsm_inst_state_chg(fi, ST_READY, 0, 0);
+ if (mgcp_ctx->terminate) {
+ /* Trigger immediate DLCX if DLCX was requested while
the FSM was
+ * busy with the previous operation */
+ LOGPFSML(fi, LOGL_ERROR, "MGW/MDCX: FSM was busy while
DLCX was requested, executing now...\n");
+ osmo_fsm_inst_dispatch(fi, EV_DLCX, mgcp_ctx);
+ } else
+ osmo_fsm_inst_dispatch(fi->proc.parent,
mgcp_ctx->parent_evt, &mgcp_ctx->conn_peer_remote);
+ break;
+ default:
+ OSMO_ASSERT(false);
+ break;
+ }
+}
+
+static void mgw_dlcx_resp_cb(struct mgcp_response *r, void *priv)
+{
+ struct osmo_fsm_inst *fi = priv;
+ struct mgcp_ctx *mgcp_ctx;
+
+ OSMO_ASSERT(fi);
+ mgcp_ctx = fi->priv;
+ OSMO_ASSERT(mgcp_ctx);
+
+ mgcp_ctx->mgw_trans_pending = false;
+
+ if (r->head.response_code != 250) {
+ LOGPFSML(fi, LOGL_ERROR,
+ "MGW/DLCX: response yields error: %d %s\n",
r->head.response_code, r->head.comment);
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_ERROR, NULL);
+ return;
+ }
+
+ osmo_fsm_inst_dispatch(fi, EV_DLCX_RESP, mgcp_ctx);
+}
+
+static void fsm_dlcx_resp_cb(struct osmo_fsm_inst *fi, uint32_t event, void
*data)
+{
+ struct mgcp_ctx *mgcp_ctx = data;
+ OSMO_ASSERT(mgcp_ctx);
+
+ switch (event) {
+ case EV_DLCX_RESP:
+ /* Rub out the connection identifier, since the connection
+ * is no longer present and we will use the connection id
+ * to know in error cases if the connection is still present
+ * or not */
+ memset(mgcp_ctx->conn_id, 0, sizeof(mgcp_ctx->conn_id));
+
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL);
+ break;
+ default:
+ OSMO_ASSERT(false);
+ break;
+ }
+}
+
+static int fsm_timeout_cb(struct osmo_fsm_inst *fi)
+{
+ struct mgcp_ctx *mgcp_ctx = fi->priv;
+ struct mgcp_client *mgcp;
+
+ OSMO_ASSERT(mgcp_ctx);
+ mgcp = mgcp_ctx->mgcp;
+ OSMO_ASSERT(mgcp);
+
+ if (fi->T == MGCP_MGW_TIMEOUT_TIMER_NR) {
+ /* Note: We were unable to communicate with the MGW,
+ * unfortunately there is no meaningful action we can take
+ * now other than giving up. */
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL);
+ } else {
+ /* Note: Ther must not be any unsolicited timers
+ * in this FSM. If so, we have serious problem. */
+ OSMO_ASSERT(false);
+ }
+
+ return 0;
+}
+
+static void fsm_cleanup_cb(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause
cause)
+{
+ struct mgcp_ctx *mgcp_ctx = fi->priv;
+ struct mgcp_client *mgcp;
+ struct msgb *msg;
+
+ OSMO_ASSERT(mgcp_ctx);
+ mgcp = mgcp_ctx->mgcp;
+ OSMO_ASSERT(mgcp);
+
+ /* If there is still a transaction pending, cancel it now. */
+ if (mgcp_ctx->mgw_trans_pending)
+ mgcp_client_cancel(mgcp, mgcp_ctx->mgw_pending_trans);
+
+ /* Should the FSM be terminated while there are still open connections
+ * on the MGW, we send an unconditional DLCX to terminate the
+ * connection. This is not the normal case. The user should always use
+ * mgcp_conn_delete() to instruct the FSM to perform a graceful exit */
+ if (strlen(mgcp_ctx->conn_id)) {
+ LOGPFSML(fi, LOGL_ERROR,
+ "MGW/DLCX: aprupt FSM termination with connections
still present, sending unconditional DLCX...\n");
+ msg = make_dlcx_msg(mgcp_ctx);
+ OSMO_ASSERT(msg);
+ mgcp_client_tx(mgcp, msg, NULL, NULL);
+ }
+
+ talloc_free(mgcp_ctx);
+}
+
+static struct osmo_fsm_state fsm_mgcp_client_states[] = {
+
+ /* Initial CRCX state. This state is immediately entered and executed
+ * when the FSM is started. The rationale is that we first have to
+ * create a connectin before we can execute other operations on that
+ * connection. */
+ [ST_CRCX] = {
+ .in_event_mask = S(EV_CRCX),
+ .out_state_mask = S(ST_CRCX_RESP),
+ .name = OSMO_STRINGIFY(ST_CRCX),
+ .action = fsm_crcx_cb,
+ },
+
+ /* Wait for the response to a CRCX operation, check and process the
+ * results, change to ST_READY afterwards. */
+ [ST_CRCX_RESP] = {
+ .in_event_mask = S(EV_CRCX_RESP),
+ .out_state_mask = S(ST_READY),
+ .name = OSMO_STRINGIFY(ST_CRCX_RESP),
+ .action = fsm_crcx_resp_cb,
+ },
+
+ /* In this idle state we wait for further operations (e.g. MDCX) that
+ * can be executed by the user using the API. There is no timeout in
+ * this state. The connection lives on until the user decides to
+ * terminate it (DLCX). */
+ [ST_READY] = {
+ .in_event_mask = S(EV_MDCX) | S(EV_DLCX),
+ .out_state_mask = S(ST_MDCX_RESP) | S(ST_DLCX_RESP),
+ .name = OSMO_STRINGIFY(ST_READY),
+ .action = fsm_ready_cb,
+ },
+
+ /* Wait for the response of a MDCX operation, check and process the
+ * results, change to ST_READY afterwards. */
+ [ST_MDCX_RESP] = {
+ .in_event_mask = S(EV_MDCX_RESP),
+ .out_state_mask = S(ST_READY),
+ .name = OSMO_STRINGIFY(ST_MDCX_RESP),
+ .action = fsm_mdcx_resp_cb,
+ },
+
+ /* Wait for the response of a DLCX operation and terminate the FSM
+ * normally. */
+ [ST_DLCX_RESP] = {
+ .in_event_mask = S(EV_DLCX_RESP),
+ .out_state_mask = 0,
+ .name = OSMO_STRINGIFY(ST_DLCX_RESP),
+ .action = fsm_dlcx_resp_cb,
+ },
+};
+
+static struct osmo_fsm fsm_mgcp_client = {
+ .name = "MGCP_CONN",
+ .states = fsm_mgcp_client_states,
+ .num_states = ARRAY_SIZE(fsm_mgcp_client_states),
+ .timer_cb = fsm_timeout_cb,
+ .cleanup = fsm_cleanup_cb,
+};
+
+/*! allocate FSM, and create a new connection on the MGW.
+ * \param[in] mgcp MGCP client descriptor.
+ * \param[in] mgcpparent_fi Parent FSM instance.
+ * \param[in] parent_term_evt Event to be sent to parent when terminating.
+ * \param[in] parent_evt Event to be sent to parent when operation is done.
+ * \param[in] conn_peer Connection parameters (ip, port...).
+ * \returns newly-allocated, initialized and registered FSM instance, NULL on
error. */
+struct osmo_fsm_inst *mgcp_conn_create(struct mgcp_client *mgcp, struct
osmo_fsm_inst *parent_fi,
+ uint32_t parent_term_evt, uint32_t
parent_evt, struct mgcp_conn_peer *conn_peer)
+{
+ struct mgcp_ctx *mgcp_ctx;
+ static bool fsm_registered = false;
+ struct osmo_fsm_inst *fi;
+ struct in_addr ip_test;
+
+ OSMO_ASSERT(parent_fi);
+ OSMO_ASSERT(mgcp);
+ OSMO_ASSERT(conn_peer);
+
+ /* Check if IP/Port informstaion in conn info makes sense */
+ if (conn_peer->port && inet_aton(conn_peer->addr, &ip_test) == 0)
+ return NULL;
+
+ /* Register the fsm description (if not already done) */
+ if (fsm_registered == false) {
+ osmo_fsm_register(&fsm_mgcp_client);
+ fsm_registered = true;
+ }
+
+ /* Allocate and configure a new fsm instance */
+ fi = osmo_fsm_inst_alloc_child(&fsm_mgcp_client, parent_fi,
parent_term_evt);
+ OSMO_ASSERT(fi);
+ mgcp_ctx = talloc_zero(fi, struct mgcp_ctx);
+ OSMO_ASSERT(mgcp_ctx);
+ mgcp_ctx->mgcp = mgcp;
+ mgcp_ctx->parent_evt = parent_evt;
+
+ memcpy(&mgcp_ctx->conn_peer_local, conn_peer,
sizeof(mgcp_ctx->conn_peer_local));
+ fi->priv = mgcp_ctx;
+
+ /* start state machine */
+ OSMO_ASSERT(fi->state == ST_CRCX);
+ osmo_fsm_inst_dispatch(fi, EV_CRCX, mgcp_ctx);
+
+ return fi;
+}
+
+/*! modify an existing connection on the MGW.
+ * \param[in] fi FSM instance.
+ * \param[in] parent_evt Event to be sent to parent when operation is done.
+ * \param[in] conn_peer New connection information (ip, port...).
+ * \returns 0 on success, -EINVAL on error. */
+int mgcp_conn_modify(struct osmo_fsm_inst *fi, uint32_t parent_evt, struct
mgcp_conn_peer *conn_peer)
+{
+ OSMO_ASSERT(fi);
+ struct mgcp_ctx *mgcp_ctx = fi->priv;
+ struct in_addr ip_test;
+
+ OSMO_ASSERT(mgcp_ctx);
+ OSMO_ASSERT(conn_peer);
+
+ /* The user must not issue an MDCX before the CRCX has completed,
+ * if this happens, it means that the parent FSM has overhead the
+ * parent_evt (mandatory!) and executed the MDCX without even
+ * waiting for the results. Another reason could be that the
+ * parent FSM got messed up */
+ OSMO_ASSERT(fi->state != ST_CRCX_RESP);
+
+ /* If the user tries to issue an MDCX while an DLCX operation is
+ * pending, there must be a serious problem with the paren FSM.
+ * Eeither the parent_term_evt (mandatory!) has been overheard,
+ * or the parant FSM got messed so badly that it still assumes
+ * a live connection although it as killed it. */
+ OSMO_ASSERT(fi->state != ST_DLCX_RESP);
+
+ /* Check if IP/Port parameters make sense */
+ if (conn_peer->port == 0)
+ return -EINVAL;
+ if (inet_aton(conn_peer->addr, &ip_test) == 0)
+ return -EINVAL;
+
+ /*! The user may supply an endpoint identifier in conn_peer. The
+ * identifier is then checked. This check is optional. Later steps do
+ * not depend on the endpoint identifier supplied here because it is
+ * already implicitly known from the CRCX phase. */
+ if (strlen(conn_peer->endpoint) && strcmp(conn_peer->endpoint,
mgcp_ctx->conn_peer_remote.endpoint))
+ return -EINVAL;
+
+ /*! Note: The call-id is implicitly known from the previous CRCX and
+ * will not be checked even when it is set in conn_peer. */
+
+ mgcp_ctx->parent_evt = parent_evt;
+ memcpy(&mgcp_ctx->conn_peer_local, conn_peer,
sizeof(mgcp_ctx->conn_peer_local));
+ osmo_fsm_inst_dispatch(fi, EV_MDCX, mgcp_ctx);
+ return 0;
+}
+
+/*! delete existing connection on the MGW, destroy FSM afterwards.
+ * \param[in] fi FSM instance. */
+void mgcp_conn_delete(struct osmo_fsm_inst *fi)
+{
+ OSMO_ASSERT(fi);
+ struct mgcp_ctx *mgcp_ctx = fi->priv;
+
+ OSMO_ASSERT(mgcp_ctx);
+
+ /* Unlink FSM from parent */
+ osmo_fsm_inst_unlink_parent(fi, NULL);
+
+ /* An error situation where the parent FSM must be killed immediately
+ * may lead into a situation where the DLCX can not be executed right
+ * at that moment because the FSM is still busy with another operation.
+ * In those cases we postpone the DLCX so that the FSM and the
+ * connections on the MGW get cleaned up gracefully. */
+ if (fi->state != ST_READY) {
+ LOGPFSML(fi, LOGL_ERROR, "MGW: operation still pending, DLCX
will be postponed.\n");
+ mgcp_ctx->terminate = true;
+ return;
+ }
+ osmo_fsm_inst_dispatch(fi, EV_DLCX, mgcp_ctx);
+}
--
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Gerrit-MessageType: newpatchset
Gerrit-Change-Id: I887ce0c15a831dffeb6251a975337b83942af566
Gerrit-PatchSet: 12
Gerrit-Project: osmo-mgw
Gerrit-Branch: master
Gerrit-Owner: dexter <pma...@sysmocom.de>
Gerrit-Reviewer: Harald Welte <lafo...@gnumonks.org>
Gerrit-Reviewer: Jenkins Builder
Gerrit-Reviewer: dexter <pma...@sysmocom.de>
