net: lib: aws_iot: Allow to bind with specific network interface

Allow the aws_iot library to bind with a specific network interface
so that the application can control which interface is used for
communication in an environment with multiple network interfaces.

Signed-off-by: Robert Lubos <[email protected]>

Author: rlubos

include/net/aws_iot.h

@@ -272,6 +272,11 @@ struct aws_iot_config {
 	 *  If not set (NULL), CONFIG_AWS_IOT_BROKER_HOST_NAME will be used.
 	 */
 	char *host_name;
+
+	/** Name of the interface that the AWS library should be bound to.
+	 *  Leave as NULL if not specified.
+	 */
+	const char *if_name;
 };
 
 /** @brief Initialize the library.

subsys/net/lib/aws_iot/src/aws_iot.c

@@ -656,6 +656,7 @@ int aws_iot_connect(const struct aws_iot_config *const config)
 		.hostname.size = (config && config->host_name) ? strlen(config->host_name) : 0,
 		.device_id.ptr = (config && config->client_id) ? config->client_id : NULL,
 		.device_id.size = (config && config->client_id) ? strlen(config->client_id) : 0,
+		.if_name = (config && config->if_name) ? config->if_name : NULL,
 	};
 
 	/* Set the hostname to CONFIG_AWS_IOT_BROKER_HOST_NAME if it was not provided