Add SetPosition into WmediumdService

Bug: 273384914
Test: cvd env cvd-1 call WmediumdService SetPosition
"mac_address:'42:00:00:00:01:00' x_pos:100.0 y_pos:100.0" &&
wmediumd_control list_stations

Change-Id: I4229047e125191a051a7fbd629530a0beac224c1

3 files changed, 92 insertions, 3 deletions

diff --git a/wmediumd/grpc.h b/wmediumd/grpc.h
new file mode 100644
index 0000000..69084f2
--- /dev/null
+++ b/wmediumd/grpc.h
@@ -0,0 +1,42 @@
+/*
+ *
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+
+#define GRPC_MSG_BUF_MAX 1024
+
+// Do not use_zero, the type of the message queue should be positive value.
+enum wmediumd_grpc_type {
+    GRPC_REQUEST = 1,
+    GRPC_RESPONSE,
+};
+
+// Do not use zero, writing zero to eventfd doesn't throw an event.
+enum wmediumd_grpc_request_type {
+    REQUEST_SET_POSITION = 1,
+};
+
+// Do not use zero, writing zero to eventfd doesn't throw an event.
+enum wmediumd_grpc_response_type {
+    RESPONSE_INVALID = 1,
+    RESPONSE_ACK,
+};
+
+struct wmediumd_grpc_message {
+    long type;
+    char data[GRPC_MSG_BUF_MAX];
+};
\ No newline at end of file
diff --git a/wmediumd/wmediumd.c b/wmediumd/wmediumd.c
index 2b1e9a4..0f4f050 100644
--- a/wmediumd/wmediumd.c
+++ b/wmediumd/wmediumd.c
@@ -39,6 +39,7 @@
 #include <unistd.h>
 #include <stdarg.h>
 #include <endian.h>
+#include <sys/msg.h>
 #include <usfstl/loop.h>
 #include <usfstl/sched.h>
 #include <usfstl/schedctrl.h>
@@ -50,6 +51,7 @@
 #include "config.h"
 #include "api.h"
 #include "pmsr.h"
+#include "grpc.h"
 
 USFSTL_SCHEDULER(scheduler);
 
@@ -1518,6 +1520,43 @@ static void close_pcapng(struct wmediumd *ctx) {
 
 static void init_pcapng(struct wmediumd *ctx, const char *filename);
 
+static void wmediumd_grpc_service_handler(struct usfstl_loop_entry *entry) {
+	struct wmediumd *ctx = entry->data;
+
+	// Receive request type from WmediumdService
+	uint64_t request_type;
+	read(entry->fd, &request_type, sizeof(uint64_t));
+
+	struct wmediumd_grpc_message request_body;
+	uint64_t response_type;
+
+	// Receive request body from WmediumdService and do the task.
+	// TODO(273384914): Support more request types.
+	switch (request_type) {
+	case REQUEST_SET_POSITION:
+		if (msgrcv(ctx->msq_id, &request_body, sizeof(struct wmediumd_set_position), GRPC_REQUEST, 0) != sizeof(struct wmediumd_set_position)) {
+			w_logf(ctx, LOG_ERR, "%s: failed to get set_position request body\n", __func__);
+		}
+
+		if (process_set_position_message(ctx, (struct wmediumd_set_position *)(request_body.data)) < 0) {
+			w_logf(ctx, LOG_ERR, "%s: failed to execute set_position\n", __func__);
+			response_type = RESPONSE_INVALID;
+		}
+		response_type = RESPONSE_ACK;
+		break;
+	default:
+		w_logf(ctx, LOG_ERR, "%s: unknown request type\n", __func__);
+		response_type = RESPONSE_INVALID;
+		break;
+	}
+
+	// TODO(273384914): Send response with response_type
+	return;
+}
+
+// TODO(273384914): Deprecate messages used in wmediumd_control after
+// implementing in wmediumd_grpc_service_handler to be used in the command
+// 'cvd env'.
 static void wmediumd_api_handler(struct usfstl_loop_entry *entry)
 {
 	struct client *client = container_of(entry, struct client, loop);
@@ -1871,7 +1910,7 @@ static void init_pcapng(struct wmediumd *ctx, const char *filename)
 #define VIRTIO_F_VERSION_1 32
 #endif
 
-int wmediumd_main(int argc, char *argv[])
+int wmediumd_main(int argc, char *argv[], int event_fd, int msq_id)
 {
 	int opt;
 	struct wmediumd ctx = {};
@@ -2022,6 +2061,13 @@ int wmediumd_main(int argc, char *argv[])
 		usfstl_sched_wallclock_init(&scheduler, 1000);
 	}
 
+	// Control event_fd to communicate WmediumdService.
+	ctx.grpc_loop.handler = wmediumd_grpc_service_handler;
+	ctx.grpc_loop.data = &ctx;
+	ctx.grpc_loop.fd = event_fd;
+	usfstl_loop_register(&ctx.grpc_loop);
+	ctx.msq_id = msq_id;
+
 	while (1) {
 		if (time_socket) {
 			usfstl_sched_next(&scheduler);
diff --git a/wmediumd/wmediumd.h b/wmediumd/wmediumd.h
index c40f111..695f871 100644
--- a/wmediumd/wmediumd.h
+++ b/wmediumd/wmediumd.h
@@ -214,9 +214,10 @@ struct client {
 
 struct wmediumd {
 	int timerfd;
+	int msq_id;
 
 	struct nl_sock *sock;
-	struct usfstl_loop_entry nl_loop;
+	struct usfstl_loop_entry nl_loop, grpc_loop;
 
 	struct usfstl_sched_ctrl *ctrl;
 
@@ -310,7 +311,7 @@ int get_max_index(void);
 extern "C" {
 #endif
 
-int wmediumd_main(int argc, char *argv[]);
+int wmediumd_main(int argc, char *argv[], int event_fd, int msq_id);
 
 #ifdef __cplusplus
 }