Json Misbehaving

[ofirshe]

Hey, I have an array of board_discovery_temp_sensor_device which utilizes the following structures:

typedef struct board_discovery_device_handle
{
    const char *device_description;
    uint32_t device_id;
    uintptr_t device;
} board_discovery_device_handle_t;

typedef struct health_monitor_configurations_temp_sensor
{
	int32_t over_temperature_limit;
	int32_t under_temperature_limit;
} health_monitor_configurations_temp_sensor_t;

typedef struct board_discovery_temp_sensor_channel
{
    const char *channel_name;
    uint32_t channel_id;
    health_monitor_configurations_temp_sensor_t channel_monitoring_params;
} board_discovery_temp_sensor_channel_t;

typedef struct board_discovery_temp_sensor_device
{
    board_discovery_device_handle_t device_handle;

    /* In case temp_sensor has channels, temp_sensor_monitoring_params will be unused because we should have controling params per channel. */
    health_monitor_configurations_temp_sensor_t temp_sensor_monitoring_params;

    /* In case temp_sensor has no channels, channels_arr_len will be assigned to 0 and channels_arr will be unused. */
    board_discovery_temp_sensor_channel_t channels_arr[BOARD_DISCOVERY_TEMP_SENSOR_MAX_CHANNELS];
    uint32_t channels_arr_len;
} board_discovery_temp_sensor_device_t;

Here are the coresponding json descriptions:
static const struct json_obj_descr g_board_discovery_device_handle_json_description[] = 
{
	JSON_OBJ_DESCR_PRIM(struct board_discovery_device_handle, device_description, JSON_TOK_STRING),
	JSON_OBJ_DESCR_PRIM(struct board_discovery_device_handle, device_id, JSON_TOK_NUMBER),
    JSON_OBJ_DESCR_PRIM(struct board_discovery_device_handle, device, JSON_TOK_NUMBER),
};

static const struct json_obj_descr g_board_discovery_temp_sensor_health_monitor_json_description[] =
{
	JSON_OBJ_DESCR_PRIM(struct health_monitor_configurations_temp_sensor, over_temperature_limit, JSON_TOK_NUMBER),
    JSON_OBJ_DESCR_PRIM(struct health_monitor_configurations_temp_sensor, under_temperature_limit, JSON_TOK_NUMBER),
};

static const struct json_obj_descr g_board_discovery_temp_sensor_channel_json_description[] =
{
    JSON_OBJ_DESCR_PRIM(struct board_discovery_temp_sensor_channel, channel_name, JSON_TOK_STRING),
    JSON_OBJ_DESCR_PRIM(struct board_discovery_temp_sensor_channel, channel_id, JSON_TOK_NUMBER),
    JSON_OBJ_DESCR_OBJECT(struct board_discovery_temp_sensor_channel, channel_monitoring_params, g_board_discovery_temp_sensor_health_monitor_json_description),
};

static const struct json_obj_descr g_board_discovery_temp_sensor_device_json_description[] =
{
	JSON_OBJ_DESCR_OBJECT(struct board_discovery_temp_sensor_device, device_handle, g_board_discovery_device_handle_json_description),
    JSON_OBJ_DESCR_OBJECT(struct board_discovery_temp_sensor_device, temp_sensor_monitoring_params, g_board_discovery_temp_sensor_health_monitor_json_description),
    JSON_OBJ_DESCR_OBJ_ARRAY(struct board_discovery_temp_sensor_device, channels_arr, BOARD_DISCOVERY_TEMP_SENSOR_MAX_CHANNELS, channels_arr_len,
				 g_board_discovery_temp_sensor_channel_json_description, ARRAY_SIZE(g_board_discovery_temp_sensor_channel_json_description)),
};

The board_discovery_temp_sensor_device array is a part of a larger structure, and here is its declaration:

board_discovery_temp_sensor_device_t temp_sensor_devices_arr[BOARD_DISCOVERY_TEMP_SENSOR_NUM_DEVICES];
 uint32_t temp_sensor_devices_arr_len;

and it's correspond json description:
/* Temperature Sensor Devices */

JSON_OBJ_DESCR_OBJ_ARRAY(struct board_discovery_devices_arr, temp_sensor_devices_arr, BOARD_DISCOVERY_TEMP_SENSOR_NUM_DEVICES,
                temp_sensor_devices_arr_len, g_board_discovery_temp_sensor_device_json_description,
                ARRAY_SIZE(g_board_discovery_temp_sensor_device_json_description)),

The array initialization (I have only two devices):
.temp_sensor_devices_arr = {
[0] = {
.device_handle = {
.device_description = "MAX31730 Temperature Sensor",
.device_id = 25,
//.device = (uint32_t)DEVICE_DT_GET(DT_ALIAS(temp_sensor_0)),
.device = (uint32_t)NULL,
},
/* temp_sensor_monitoring_params variable is unused for this device because it has channels. */

        /* Channels */
        .channels_arr = {
            [0] = {
                .channel_name = "Temperature Sensor Channel 0",
                .channel_id = 0,
                .channel_monitoring_params = {
                    .over_temperature_limit = 70,
                    .under_temperature_limit = 50,
                },
            },
            [1] = {
                .channel_name = "Temperature Sensor Channel 1",
                .channel_id = 1,
                .channel_monitoring_params = {
                    .over_temperature_limit = 70,
                    .under_temperature_limit = 50,
                },
            },
            [2] = {
                .channel_name = "Temperature Sensor Channel 2",
                .channel_id = 2,
                .channel_monitoring_params = {
                    .over_temperature_limit = 70,
                    .under_temperature_limit = 50,
                },
            },
        },
        .channels_arr_len = 3,
        /* End Of Channels */
    },
    [1] = {
        .device_handle = {
            .device_description = "Protean-tech Temperature Sensor",
            .device_id = 26,
            //.device = (uint32_t)DEVICE_DT_GET(DT_ALIAS(temp_sensor_1)), 
            .device = (uint32_t)NULL,
        },
        .temp_sensor_monitoring_params = {
            .over_temperature_limit = 70,
            .under_temperature_limit = 50,
        },
        /* channels_arr variable is unused for this device because it has no channels. */
        .channels_arr_len = 0,
    },
},
.temp_sensor_devices_arr_len = 0,

When I print the output json of this array it looks like this:

"temp_sensor_devices_arr":[{"device_handle":{"device_description":"MAX31730 Temperature Sensor","device_id":9,"device":0},"temp_sensor_monitoring_params":{"over_temperature_limit":0,"under_temperature_limit":0},"channels_arr":[{"channel_name":"Temperature Sensor Channel 0","channel_id":0,"channel_monitoring_params":{"over_temperature_limit":70,"under_temperature_limit":50}},{"channel_name":"Temperature Sensor Channel 1","channel_id":1,"channel_monitoring_params":{"over_temperature_limit":70,"under_temperature_limit":50}},{"channel_name":"Temperature Sensor Channel 2","channel_id":2,"channel_monitoring_params":{"over_temperature_limit":70,"under_temperature_limit":50}}]},
                           {"device_handle":{"device_description":"O\\fF\x16F\x07i\\nFD\xea\x06\\b\x87\xb0\x05F\x97\xf8$\x10\xc8\xf3\x0b\\b8h","device_id":1610754939,"device":10},"temp_sensor_monitoring_params":{"over_temperature_limit":0,"under_temperature_limit":70},"channels_arr":[]}], 

While debugging, I observed that after finishing the encoding of temp_sensor_devices_arr[0], the val pointer in the encode function advanced to the offset of the channels_arr_len field. This explains why, when inspecting the json_escape_internal() function in the debugger, the value of the str pointer is 0x3. I also verified against the actual array, and it corresponds to the address of channels_arr_len from element 0. However, it should actually be the start address of temp_sensor_devices_arr[1]. The channels_arr_len field should be encapsulated within the call to JSON_OBJ_DESCR_OBJ_ARRAY, and it should be taken into account when calculating the offset of each object.

I would greatly appreciate any assistance that can be provided.

Thanks,
Ofir.