Mbed OS Reference | NetworkInterface.h Source File

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 /*
  * Copyright (c) 2015 ARM Limited
  *
  * 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.
  */
 
 /** @file NetworkInterface.h Network Interface base class */
 /** @addtogroup netinterface
  * Network Interface classes
  * @{ */
 
 
 #ifndef NETWORK_INTERFACE_H
 #define NETWORK_INTERFACE_H
 
 #include "netsocket/nsapi_types.h"
 #include "netsocket/SocketAddress.h"
 #include "Callback.h"
 #include "DNS.h"
 
 
 // Predeclared classes
 class NetworkStack;
 class EthInterface;
 class WiFiInterface;
 class MeshInterface;
 class CellularInterface;
 class EMACInterface;
 class PPPInterface;
 
 /** Common interface that is shared between network devices.
  *
  */
 class NetworkInterface: public DNS {
 public:
 
     virtual ~NetworkInterface();
 
     /** Return the default network interface.
      *
      * Returns the default network interface, as determined by JSON option
      * target.network-default-interface-type or other overrides.
      *
      * The type of the interface returned can be tested by calling ethInterface(),
      * wifiInterface(), meshInterface(), cellularInterface(), emacInterface() and checking
      * for NULL pointers.
      *
      * The default behavior is to return the default interface for the
      * interface type specified by target.network-default-interface-type. Targets
      * should set this in their targets.json to guide default selection,
      * and applications may override.
      *
      * The interface returned should be already configured for use such that its
      * connect() method works with no parameters. For connection types needing
      * configuration, settings should normally be obtained from JSON - the
      * settings for the core types are under the "nsapi" JSON config tree.
      *
      * The list of possible settings for default interface type is open-ended,
      * as is the number of possible providers. Core providers are:
      *
      * * ETHERNET: EthernetInterface, using default EMAC and OnboardNetworkStack
      * * MESH: ThreadInterface or LoWPANNDInterface, using default NanostackRfPhy
      * * CELLULAR: OnboardModemInterface
      * * WIFI: None - always provided by a specific class
      *
      * Specific drivers may be activated by other settings of the
      * default-network-interface-type configuration.  This will depend on the
      * target and the driver. For example a board may have its default setting
      * as "AUTO" which causes it to autodetect an Ethernet cable. This should
      * be described in the target's documentation.
      *
      * An application can override all target settings by implementing
      * NetworkInterface::get_default_instance() themselves - the default
      * definition is weak, and calls get_target_default_instance().
      */
     static NetworkInterface *get_default_instance();
 
     /** Set network interface as default one.
      */
     virtual void set_as_default();
 
     /** Get the local MAC address.
      *
      *  Provided MAC address is intended for info or debug purposes and
      *  may be not provided if the underlying network interface does not
      *  provide a MAC address.
      *
      *  @return         Null-terminated representation of the local MAC address
      *                  or null if no MAC address is available.
      */
     virtual const char *get_mac_address();
 
     /** Get the local IP address
      *
      *  @return         Null-terminated representation of the local IP address
      *                  or null if not yet connected
      */
     virtual const char *get_ip_address();
 
     /** Get the local network mask.
      *
      *  @return         Null-terminated representation of the local network mask
      *                  or null if no network mask has been received.
      */
     virtual const char *get_netmask();
 
     /** Get the local gateway.
      *
      *  @return         Null-terminated representation of the local gateway
      *                  or null if no network mask has been received.
      */
     virtual const char *get_gateway();
 
     /** Get the network interface name
      *
      *  @return         Null-terminated representation of the network interface name
      *                  or null if  interface not exists
      */
     virtual char *get_interface_name(char *interface_name);
 
     /** Configure this network interface to use a static IP address.
      *  Implicitly disables DHCP, which can be enabled in set_dhcp.
      *  Requires that the network is disconnected.
      *
      *  @param ip_address Null-terminated representation of the local IP address
      *  @param netmask    Null-terminated representation of the local network mask
      *  @param gateway    Null-terminated representation of the local gateway
      *  @return           NSAPI_ERROR_OK on success, negative error code on failure
      */
     virtual nsapi_error_t set_network(const char *ip_address, const char *netmask, const char *gateway);
 
     /** Enable or disable DHCP on connecting the network.
      *
      *  Enabled by default unless a static IP address has been assigned. Requires
      *  that the network is disconnected.
      *
      *  @param dhcp     True to enable DHCP.
      *  @return         NSAPI_ERROR_OK on success, negative error code on failure.
      */
     virtual nsapi_error_t set_dhcp(bool dhcp);
 
     /** Connect to a network.
      *
      * This blocks until connection is established, but asynchronous operation can be enabled
      * by calling NetworkInterface::set_blocking(false).
      *
      * In asynchronous mode this starts the connection sequence and returns immediately.
      * Status of the connection can then checked from NetworkInterface::get_connection_status()
      * or from status callbacks.
      *
      * NetworkInterface internally handles reconnections until disconnect() is called.
      *
      * @return NSAPI_ERROR_OK if connection established in blocking mode.
      * @return NSAPI_ERROR_OK if asynchronous operation started.
      * @return NSAPI_ERROR_BUSY if asynchronous operation cannot be started.
                                 Implementation guarantees event generation, which can be used as an
                                 trigger to reissue the rejected request.
      * @return NSAPI_ERROR_IS_CONNECTED if already connected.
      * @return negative error code on failure.
      */
     virtual nsapi_error_t connect() = 0;
 
     /** Disconnect from the network
      *
      *  This blocks until interface is disconnected, unless interface is set to
      *  asynchronous (non-blocking) mode by calling NetworkInterface::set_blocking(false).
      *
      * @return NSAPI_ERROR_OK on successfully disconnected in blocking mode.
      * @return NSAPI_ERROR_OK if asynchronous operation started.
      * @return NSAPI_ERROR_BUSY if asynchronous operation cannot be started.
                                 Implementation guarantees event generation, which can be used as an
                                 trigger to reissue the rejected request.
      * @return NSAPI_ERROR_NO_CONNECTION if already disconnected.
      * @return negative error code on failure.
      */
     virtual nsapi_error_t disconnect() = 0;
 
     /** Translate a hostname to an IP address with specific version using network interface name.
      *
      *  The hostname may be either a domain name or an IP address. If the
      *  hostname is an IP address, no network transactions will be performed.
      *
      *  If no stack-specific DNS resolution is provided, the hostname
      *  will be resolve using a UDP socket on the stack.
      *
      *  @param host     Hostname to resolve.
      *  @param address  Pointer to a SocketAddress to store the result.
      *  @param version  IP version of address to resolve, NSAPI_UNSPEC indicates
      *                  version is chosen by the stack (defaults to NSAPI_UNSPEC).
      *  @param interface_name  Network interface name
      *  @return         NSAPI_ERROR_OK on success, negative error code on failure.
      */
     virtual nsapi_error_t gethostbyname(const char *host,
                                         SocketAddress *address, nsapi_version_t version = NSAPI_UNSPEC, const char *interface_name = NULL);
 
     /** Hostname translation callback (for use with gethostbyname_async()).
      *
      *  Callback will be called after DNS resolution completes or a failure occurs.
      *
      *  @note Callback should not take more than 10ms to execute, otherwise it might
      *  prevent underlying thread processing. A portable user of the callback
      *  should not make calls to network operations due to stack size limitations.
      *  The callback should not perform expensive operations such as socket recv/send
      *  calls or blocking operations.
      *
      *  @param result  NSAPI_ERROR_OK on success, negative error code on failure.
      *  @param address On success, destination for the host SocketAddress.
      */
     typedef mbed::Callback<void (nsapi_error_t result, SocketAddress *address)> hostbyname_cb_t;
 
     /** Translate a hostname to an IP address (asynchronous) using network interface name.
      *
      *  The hostname may be either a domain name or a dotted IP address. If the
      *  hostname is an IP address, no network transactions will be performed.
      *
      *  If no stack-specific DNS resolution is provided, the hostname
      *  will be resolve using a UDP socket on the stack.
      *
      *  Call is non-blocking. Result of the DNS operation is returned by the callback.
      *  If this function returns failure, callback will not be called. In case result
      *  is success (IP address was found from DNS cache), callback will be called
      *  before function returns.
      *
      *  @param host     Hostname to resolve.
      *  @param callback Callback that is called for result.
      *  @param version  IP version of address to resolve, NSAPI_UNSPEC indicates
      *                  version is chosen by the stack (defaults to NSAPI_UNSPEC).
      *  @param interface_name  Network interface name
      *  @return         0 on immediate success,
      *                  negative error code on immediate failure or
      *                  a positive unique id that represents the hostname translation operation
      *                  and can be passed to cancel.
      */
     virtual nsapi_value_or_error_t gethostbyname_async(const char *host, hostbyname_cb_t callback, nsapi_version_t version = NSAPI_UNSPEC,
                                                        const char *interface_name = NULL);
 
     /** Cancel asynchronous hostname translation.
      *
      *  When translation is cancelled, callback will not be called.
      *
      *  @param id       Unique id of the hostname translation operation (returned
      *                  by gethostbyname_async)
      *  @return         NSAPI_ERROR_OK on success, negative error code on failure.
      */
     virtual nsapi_error_t gethostbyname_async_cancel(int id);
 
     /** Add a domain name server to list of servers to query
      *
      *  @param address  Address for the dns host.
      *  @return         NSAPI_ERROR_OK on success, negative error code on failure.
      */
     virtual nsapi_error_t add_dns_server(const SocketAddress &address, const char *interface_name);
 
     /** Register callback for status reporting.
      *
      *  The specified status callback function will be called on status changes
      *  on the network. The parameters on the callback are the event type and
      *  event-type dependent reason parameter. Only one callback can be registered at a time.
      *
      *  To unregister a callback call with status_cb parameter as a zero.
      *
      *  *NOTE:* Any callbacks registered with this function will be overwritten if
      *          add_event_listener() API is used.
      *
      *  @param status_cb The callback for status changes.
      */
     virtual void attach(mbed::Callback<void(nsapi_event_t, intptr_t)> status_cb);
 
     /** Add event listener for interface.
      *
      * This API allows multiple callback to be registered for a single interface.
      * When first called, internal list of event handlers are created and registered to
      * interface through attach() API.
      *
      * Application may only use attach() or add_event_listener() interface. Mixing usage
      * of both leads to undefined behavior.
      *
      *  @param status_cb The callback for status changes.
      */
     void add_event_listener(mbed::Callback<void(nsapi_event_t, intptr_t)> status_cb);
 
     /** Remove event listener from interface.
      *
      * Remove previously added callback from the handler list.
      *
      *  @param status_cb The callback to unregister.
      */
     void remove_event_listener(mbed::Callback<void(nsapi_event_t, intptr_t)> status_cb);
 
     /** Get the connection status.
      *
      *  @return The connection status (@see nsapi_types.h).
      */
     virtual nsapi_connection_status_t get_connection_status() const;
 
     /** Set asynchronous operation of connect() and disconnect() calls.
      *
      * By default, interfaces are in synchronous mode which means that
      * connect() or disconnect() blocks until it reach the target state or requested operation fails.
      *
      * @param blocking Use false to set NetworkInterface in asynchronous mode.
      * @return NSAPI_ERROR_OK on success
      * @return NSAPI_ERROR_UNSUPPORTED if driver does not support asynchronous mode.
      * @return negative error code on failure.
      */
     virtual nsapi_error_t set_blocking(bool blocking);
 
     /** Return pointer to an EthInterface.
      * @return Pointer to requested interface type or NULL if this class doesn't implement the interface.
      */
     virtual EthInterface *ethInterface()
     {
         return 0;
     }
 
     /** Return pointer to a WiFiInterface.
      * @return Pointer to requested interface type or NULL if this class doesn't implement the interface.
      */
     virtual WiFiInterface *wifiInterface()
     {
         return 0;
     }
 
     /** Return pointer to a MeshInterface.
      * @return Pointer to requested interface type or NULL if this class doesn't implement the interface.
      */
     virtual MeshInterface *meshInterface()
     {
         return 0;
     }
 
     /** Return pointer to a CellularInterface.
      * @return Pointer to requested interface type or NULL if this class doesn't implement the interface.
      * @deprecated CellularBase migrated to CellularInterface - use cellularInterface()
      */
     MBED_DEPRECATED_SINCE("mbed-os-5.12", "CellularBase migrated to CellularInterface - use cellularInterface()")
     virtual CellularInterface *cellularBase() // virtual retained for binary compatibility
     {
         return 0;
     }
 
     /** Return pointer to an EMACInterface.
      * @return Pointer to requested interface type or NULL if this class doesn't implement the interface.
      */
     virtual EMACInterface *emacInterface()
     {
         return 0;
     }
 
 #if !defined(DOXYGEN_ONLY)
 
 protected:
     friend class InternetSocket;
     friend class UDPSocket;
     friend class TCPSocket;
     friend class TCPServer;
     friend class SocketAddress;
     template <typename IF>
     friend NetworkStack *nsapi_create_stack(IF *iface);
 
     /** Provide access to the NetworkStack object
      *
      *  @return The underlying NetworkStack object
      */
     virtual NetworkStack *get_stack() = 0;
 
     /** Get the target's default network instance.
      *
      * This method can be overridden by the target. Default implementations
      * are provided weakly by various subsystems as described in
      * NetworkInterface::get_default_instance(), so targets should not
      * need to override in simple cases.
      *
      * If a target has more elaborate interface selection, it can completely
      * override this behavior by implementing
      * NetworkInterface::get_target_default_instance() themselves, either
      * unconditionally, or for a specific network-default-interface-type setting
      *
      * For example, a device with both Ethernet and Wi-fi could be set up its
      * target so that:
      *    * DEVICE_EMAC is set, and it provides EMAC::get_default_instance(),
      *      which means EthernetInterface provides EthInterface::get_target_instance()
      *      based on that EMAC.
      *    * It provides WifiInterface::get_target_default_instance().
      *    * The core will route NetworkInterface::get_default_instance() to
      *      either of those if network-default-interface-type is set to
      *      ETHERNET or WIFI.
      *    * The board overrides NetworkInterface::get_target_default_instance()
      *      if network-default-interface-type is set to AUTO. This returns
      *      either EthInterface::get_default_instance() or WiFIInterface::get_default_instance()
      *      depending on a cable detection.
      *
      *
      * performs the search described by get_default_instance.
      */
     static NetworkInterface *get_target_default_instance();
 #endif //!defined(DOXYGEN_ONLY)
 
 public:
     /** Set default parameters on an interface.
      *
      * A network interface instantiated directly or using calls such as
      * WiFiInterface::get_default_instance() is initially unconfigured.
      * This call can be used to set the default parameters that would
      * have been set if the interface had been requested using
      * NetworkInterface::get_default_instance() (see nsapi JSON
      * configuration).
      */
     virtual void set_default_parameters();
 
     /** Return pointer to a CellularInterface.
      * @return Pointer to requested interface type or NULL if this class doesn't implement the interface.
      */
     virtual CellularInterface *cellularInterface()
     {
         return 0;
     }
 };
 
 #endif
 
 /** @}*/
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