net: lwm2m: adds LwM2M specific shell command

First available subcommand is for doing a send operation. Send operation
is supported by the LwM2M version 1.1.

Signed-off-by: Veijo Pesonen <veijo.pesonen@nordicsemi.no>

include/zephyr/net/lwm2m.h

@@ -1218,5 +1218,13 @@ char *lwm2m_path_log_strdup(char *buf, struct lwm2m_obj_path *path);
 int lwm2m_engine_send(struct lwm2m_ctx *ctx, char const *path_list[], uint8_t path_list_size,
 		      bool confirmation_request);
 
+/** 
+ * @brief Returns LwM2M client context
+ *
+ * @return ctx LwM2M context
+ *
+ */
+struct lwm2m_ctx *lwm2m_rd_client_ctx(void);
+
 #endif	/* ZEPHYR_INCLUDE_NET_LWM2M_H_ */
 /**@}  */

subsys/net/lib/lwm2m/CMakeLists.txt

@@ -94,4 +94,9 @@ zephyr_library_sources_ifdef(CONFIG_LWM2M_UCIFI_BATTERY
     ucifi_battery.c
     )
 
+# Shell commands
+zephyr_library_sources_ifdef(CONFIG_LWM2M_SHELL
+    lwm2m_shell.c
+)
+
 zephyr_library_link_libraries_ifdef(CONFIG_MBEDTLS mbedTLS)

subsys/net/lib/lwm2m/Kconfig

@@ -32,6 +32,13 @@ config LWM2M_VERSION_1_1
 
 endchoice
 
+config LWM2M_SHELL
+	bool "LwM2M shell utilities"
+	select SHELL
+	help
+	  Activate shell module that provides LwM2M commands like
+	  send to the console.
+
 config LWM2M_DTLS_SUPPORT
 	bool "DTLS support in the LwM2M client"
 	select TLS_CREDENTIALS

subsys/net/lib/lwm2m/lwm2m_rd_client.c

@@ -1149,6 +1149,11 @@ void lwm2m_rd_client_update(void)
 	engine_trigger_update(false);
 }
 
+struct lwm2m_ctx *lwm2m_rd_client_ctx(void)
+{
+	return client.ctx;
+}
+
 static int lwm2m_rd_client_init(const struct device *dev)
 {
 	k_mutex_init(&client.mutex);

subsys/net/lib/lwm2m/lwm2m_shell.c

@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2022 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#define LOG_MODULE_NAME net_lwm2m_shell
+#define LOG_LEVEL CONFIG_LWM2M_LOG_LEVEL
+
+#include <logging/log.h>
+LOG_MODULE_REGISTER(LOG_MODULE_NAME);
+
+#include <stddef.h>
+#include <stdlib.h>
+
+#include <kernel.h>
+#include <net/lwm2m.h>
+#include <shell/shell.h>
+
+#define LWM2M_HELP_CMD "LwM2M commands"
+#define LWM2M_HELP_SEND "LwM2M SEND operation\nsend [OPTION]... [PATH]...\n" \
+	"-n\tSend as non-confirmable\n" \
+	"Paths are inserted without leading '/'\n" \
+	"Root-level operation is unsupported"
+
+static int cmd_send(const struct shell *sh, size_t argc, char **argv)
+{
+	int ret = 0;
+	struct lwm2m_ctx *ctx = lwm2m_rd_client_ctx();
+	int path_cnt = argc - 1;
+	bool confirmable = true;
+	int ignore_cnt = 1; /* Subcmd + arguments preceding the path list */
+
+	if (!ctx) {
+		shell_error(sh, "no lwm2m context yet\n");
+		return -ENOEXEC;
+	}
+
+	if (argc < 2) {
+		shell_error(sh, "no arguments or path(s)\n");
+		shell_help(sh);
+		return -EINVAL;
+	}
+
+	if (strcmp(argv[1], "-n") == 0) {
+		confirmable = false;
+		path_cnt--;
+		ignore_cnt++;
+	}
+
+	if ((argc - ignore_cnt) == 0) {
+		shell_error(sh, "no path(s)\n");
+		shell_help(sh);
+		return -EINVAL;
+	}
+
+	for (int idx = ignore_cnt; idx < argc; idx++) {
+		if (argv[idx][0] < '0' || argv[idx][0] > '9') {
+			shell_error(sh, "invalid path: %s\n", argv[idx]);
+			shell_help(sh);
+			return -EINVAL;
+		}
+	}
+
+	ret = lwm2m_engine_send(ctx, (const char **)&(argv[ignore_cnt]),
+			path_cnt, confirmable);
+	if (ret < 0) {
+		shell_error(sh, "can't do send operation, request failed\n");
+		return -ENOEXEC;
+	}
+
+	return 0;
+}
+
+SHELL_STATIC_SUBCMD_SET_CREATE(sub_lwm2m,
+			       SHELL_COND_CMD_ARG(CONFIG_LWM2M_VERSION_1_1, send, NULL,
+						  LWM2M_HELP_SEND, cmd_send, 1, 9),
+			       SHELL_SUBCMD_SET_END);
+
+SHELL_COND_CMD_ARG_REGISTER(CONFIG_LWM2M_SHELL, lwm2m, &sub_lwm2m, LWM2M_HELP_CMD, NULL, 1, 0);