File content as of revision 44:33dd78697616:

// Copyright (c) Microsoft. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.

/** @file iothub_client_ll.h
*	@brief	 APIs that allow a user (usually a device) to communicate
*		     with an Azure IoTHub.
*
*	@details IoTHubClient_LL is a module that allows a user (usually a
*			 device) to communicate with an Azure IoTHub. It can send events
*			 and receive messages. At any given moment in time there can only
*			 be at most 1 message callback function.
*
*			 This API surface contains a set of APIs that allows the user to
*			 interact with the lower layer portion of the IoTHubClient. These APIs
*			 contain @c _LL_ in their name, but retain the same functionality like the
*			 @c IoTHubClient_... APIs, with one difference. If the @c _LL_ APIs are
*			 used then the user is responsible for scheduling when the actual work done
*			 by the IoTHubClient happens (when the data is sent/received on/from the wire).
*			 This is useful for constrained devices where spinning a separate thread is
*			 often not desired.
*/

#ifndef IOTHUB_CLIENT_LL_H
#define IOTHUB_CLIENT_LL_H

#include "azure_c_shared_utility/macro_utils.h"

#define IOTHUB_CLIENT_RESULT_VALUES       \
    IOTHUB_CLIENT_OK,                     \
    IOTHUB_CLIENT_INVALID_ARG,            \
    IOTHUB_CLIENT_ERROR,                  \
    IOTHUB_CLIENT_INVALID_SIZE,           \
    IOTHUB_CLIENT_INDEFINITE_TIME         \

/** @brief Enumeration specifying the status of calls to various APIs in this module.
*/

DEFINE_ENUM(IOTHUB_CLIENT_RESULT, IOTHUB_CLIENT_RESULT_VALUES);

typedef struct IOTHUBTRANSPORT_CONFIG_TAG IOTHUBTRANSPORT_CONFIG;

typedef struct IOTHUB_CLIENT_LL_HANDLE_DATA_TAG* IOTHUB_CLIENT_LL_HANDLE;

#define IOTHUB_CLIENT_STATUS_VALUES       \
    IOTHUB_CLIENT_SEND_STATUS_IDLE,       \
    IOTHUB_CLIENT_SEND_STATUS_BUSY        \

/** @brief Enumeration returned by the ::IoTHubClient_LL_GetSendStatus
*		   API to indicate the current sending status of the IoT Hub client.
*/
DEFINE_ENUM(IOTHUB_CLIENT_STATUS, IOTHUB_CLIENT_STATUS_VALUES);

#include "azure_c_shared_utility/agenttime.h"
#include "azure_c_shared_utility/xio.h"
#include "azure_c_shared_utility/doublylinkedlist.h"
#include "iothub_message.h"
#include "iothub_transport_ll.h"

#ifdef __cplusplus
extern "C"
{
#endif

#define IOTHUB_CLIENT_CONFIRMATION_RESULT_VALUES     \
    IOTHUB_CLIENT_CONFIRMATION_OK,                   \
    IOTHUB_CLIENT_CONFIRMATION_BECAUSE_DESTROY,      \
    IOTHUB_CLIENT_CONFIRMATION_MESSAGE_TIMEOUT,      \
    IOTHUB_CLIENT_CONFIRMATION_ERROR                 \

	/** @brief Enumeration passed in by the IoT Hub when the event confirmation
	*		   callback is invoked to indicate status of the event processing in
	*		   the hub.
	*/
	DEFINE_ENUM(IOTHUB_CLIENT_CONFIRMATION_RESULT, IOTHUB_CLIENT_CONFIRMATION_RESULT_VALUES);

#define TRANSPORT_TYPE_VALUES \
    TRANSPORT_LL, /*LL comes from "LowLevel" */ \
    TRANSPORT_THREADED

	DEFINE_ENUM(TRANSPORT_TYPE, TRANSPORT_TYPE_VALUES);

#define IOTHUBMESSAGE_DISPOSITION_RESULT_VALUES \
    IOTHUBMESSAGE_ACCEPTED, \
    IOTHUBMESSAGE_REJECTED, \
    IOTHUBMESSAGE_ABANDONED

	/** @brief Enumeration returned by the callback which is invoked whenever the
	*		   IoT Hub sends a message to the device.
	*/
	DEFINE_ENUM(IOTHUBMESSAGE_DISPOSITION_RESULT, IOTHUBMESSAGE_DISPOSITION_RESULT_VALUES);

	
	typedef void(*IOTHUB_CLIENT_EVENT_CONFIRMATION_CALLBACK)(IOTHUB_CLIENT_CONFIRMATION_RESULT result, void* userContextCallback);
	typedef IOTHUBMESSAGE_DISPOSITION_RESULT (*IOTHUB_CLIENT_MESSAGE_CALLBACK_ASYNC)(IOTHUB_MESSAGE_HANDLE message, void* userContextCallback);
	typedef const TRANSPORT_PROVIDER*(*IOTHUB_CLIENT_TRANSPORT_PROVIDER)(void);

	/** @brief	This struct captures IoTHub client configuration. */
	typedef struct IOTHUB_CLIENT_CONFIG_TAG
	{
		/** @brief A function pointer that is passed into the @c IoTHubClientCreate.
		*	A function definition for AMQP is defined in the include @c iothubtransportamqp.h.
		*   A function definition for HTTP is defined in the include @c iothubtransporthttp.h
		*   A function definition for MQTT is defined in the include @c iothubtransportmqtt.h */
		IOTHUB_CLIENT_TRANSPORT_PROVIDER protocol;

		/** @brief	A string that identifies the device. */
		const char* deviceId;

		/** @brief	The device key used to authenticate the device. */
		const char* deviceKey;

		/** @brief	The device SAS Token used to authenticate the device in place of device key. */
		const char* deviceSasToken;

		/** @brief	The IoT Hub name to which the device is connecting. */
		const char* iotHubName;

		/** @brief	IoT Hub suffix goes here, e.g., private.azure-devices-int.net. */
		const char* iotHubSuffix;

		const char* protocolGatewayHostName;
	} IOTHUB_CLIENT_CONFIG;

	/** @brief	This struct captures IoTHub client device configuration. */
	typedef struct IOTHUB_CLIENT_DEVICE_CONFIG_TAG
	{
		/** @brief A function pointer that is passed into the @c IoTHubClientCreate.
		*	A function definition for AMQP is defined in the include @c iothubtransportamqp.h.
		*   A function definition for HTTP is defined in the include @c iothubtransporthttp.h
		*   A function definition for MQTT is defined in the include @c iothubtransportmqtt.h */
		IOTHUB_CLIENT_TRANSPORT_PROVIDER protocol;

		/** @brief a transport handle implementing the protocol */
		void * transportHandle;

		/** @brief	A string that identifies the device. */
		const char* deviceId;

		/** @brief	The device key used to authenticate the device. */
		const char* deviceKey;

		/** @brief	The device SAS Token used to authenticate the device in place of device key. */
		const char* deviceSasToken;
	} IOTHUB_CLIENT_DEVICE_CONFIG;

	/** @brief	This struct captures IoTHub transport configuration. */
	typedef struct IOTHUBTRANSPORT_CONFIG_TAG
	{
		const IOTHUB_CLIENT_CONFIG* upperConfig;
		PDLIST_ENTRY waitingToSend;
	}IOTHUBTRANSPORT_CONFIG;


	/**
	* @brief	Creates a IoT Hub client for communication with an existing
	* 			IoT Hub using the specified connection string parameter.
	*
	* @param	connectionString	Pointer to a character string
	* @param	protocol			Function pointer for protocol implementation
	*
	*			Sample connection string:
	*				<blockquote>
	*					<pre>HostName=[IoT Hub name goes here].[IoT Hub suffix goes here, e.g., private.azure-devices-int.net];DeviceId=[Device ID goes here];SharedAccessKey=[Device key goes here];</pre>
	*				</blockquote>
	*
	* @return	A non-NULL @c IOTHUB_CLIENT_LL_HANDLE value that is used when
	* 			invoking other functions for IoT Hub client and @c NULL on failure.
	*/
	extern IOTHUB_CLIENT_LL_HANDLE IoTHubClient_LL_CreateFromConnectionString(const char* connectionString, IOTHUB_CLIENT_TRANSPORT_PROVIDER protocol);

	/**
	* @brief	Creates a IoT Hub client for communication with an existing IoT
	* 			Hub using the specified parameters.
	*
	* @param	config	Pointer to an @c IOTHUB_CLIENT_CONFIG structure
	*
	*			The API does not allow sharing of a connection across multiple
	*			devices. This is a blocking call.
	*
	* @return	A non-NULL @c IOTHUB_CLIENT_LL_HANDLE value that is used when
	* 			invoking other functions for IoT Hub client and @c NULL on failure.
	*/
	extern IOTHUB_CLIENT_LL_HANDLE IoTHubClient_LL_Create(const IOTHUB_CLIENT_CONFIG* config);

	/**
	* @brief	Creates a IoT Hub client for communication with an existing IoT
	* 			Hub using an existing transport.
	*
	* @param	config	Pointer to an @c IOTHUB_CLIENT_DEVICE_CONFIG structure
	*
	*			The API *allows* sharing of a connection across multiple
	*			devices. This is a blocking call.
	*
	* @return	A non-NULL @c IOTHUB_CLIENT_LL_HANDLE value that is used when
	* 			invoking other functions for IoT Hub client and @c NULL on failure.
	*/
	extern IOTHUB_CLIENT_LL_HANDLE IoTHubClient_LL_CreateWithTransport(const IOTHUB_CLIENT_DEVICE_CONFIG * config);

	/**
	* @brief	Disposes of resources allocated by the IoT Hub client. This is a
	* 			blocking call.
	*
	* @param	iotHubClientHandle	The handle created by a call to the create function.
	*/
	extern void IoTHubClient_LL_Destroy(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle);

	/**
	* @brief	Asynchronous call to send the message specified by @p eventMessageHandle.
	*
	* @param	iotHubClientHandle		   	The handle created by a call to the create function.
	* @param	eventMessageHandle		   	The handle to an IoT Hub message.
	* @param	eventConfirmationCallback  	The callback specified by the device for receiving
	* 										confirmation of the delivery of the IoT Hub message.
	* 										This callback can be expected to invoke the
	* 										::IoTHubClient_LL_SendEventAsync function for the
	* 										same message in an attempt to retry sending a failing
	* 										message. The user can specify a @c NULL value here to
	* 										indicate that no callback is required.
	* @param	userContextCallback			User specified context that will be provided to the
	* 										callback. This can be @c NULL.
	*
	*			@b NOTE: The application behavior is undefined if the user calls
	*			the ::IoTHubClient_LL_Destroy function from within any callback.
	*
	* @return	IOTHUB_CLIENT_OK upon success or an error code upon failure.
	*/
	extern IOTHUB_CLIENT_RESULT IoTHubClient_LL_SendEventAsync(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle, IOTHUB_MESSAGE_HANDLE eventMessageHandle, IOTHUB_CLIENT_EVENT_CONFIRMATION_CALLBACK eventConfirmationCallback, void* userContextCallback);

	/**
	* @brief	This function returns the current sending status for IoTHubClient.
	*
	* @param	iotHubClientHandle		The handle created by a call to the create function.
	* @param	iotHubClientStatus		The sending state is populated at the address pointed
	* 									at by this parameter. The value will be set to
	* 									@c IOTHUBCLIENT_SENDSTATUS_IDLE if there is currently
	* 								    no item to be sent and @c IOTHUBCLIENT_SENDSTATUS_BUSY
	* 								    if there are.
	*
	* @return	IOTHUB_CLIENT_OK upon success or an error code upon failure.
	*/
	extern IOTHUB_CLIENT_RESULT IoTHubClient_LL_GetSendStatus(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle, IOTHUB_CLIENT_STATUS *iotHubClientStatus);

	/**
	* @brief	Sets up the message callback to be invoked when IoT Hub issues a
	* 			message to the device. This is a blocking call.
	*
	* @param	iotHubClientHandle		   	The handle created by a call to the create function.
	* @param	messageCallback     	   	The callback specified by the device for receiving
	* 										messages from IoT Hub.
	* @param	userContextCallback			User specified context that will be provided to the
	* 										callback. This can be @c NULL.
	*
	*			@b NOTE: The application behavior is undefined if the user calls
	*			the ::IoTHubClient_LL_Destroy function from within any callback.
	*
	* @return	IOTHUB_CLIENT_OK upon success or an error code upon failure.
	*/
	extern IOTHUB_CLIENT_RESULT IoTHubClient_LL_SetMessageCallback(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle, IOTHUB_CLIENT_MESSAGE_CALLBACK_ASYNC messageCallback, void* userContextCallback);

	/**
	* @brief	This function returns in the out parameter @p lastMessageReceiveTime
	* 			what was the value of the @c time function when the last message was
	* 			received at the client.
	*
	* @param	iotHubClientHandle				The handle created by a call to the create function.
	* @param	lastMessageReceiveTime  		Out parameter containing the value of @c time function
	* 											when the last message was received.
	*
	* @return	IOTHUB_CLIENT_OK upon success or an error code upon failure.
	*/
	extern IOTHUB_CLIENT_RESULT IoTHubClient_LL_GetLastMessageReceiveTime(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle, time_t* lastMessageReceiveTime);

	/**
	* @brief	This function is meant to be called by the user when work
	* 			(sending/receiving) can be done by the IoTHubClient.
	*
	* @param	iotHubClientHandle	The handle created by a call to the create function.
	*
	*			All IoTHubClient interactions (in regards to network traffic
	*			and/or user level callbacks) are the effect of calling this
	*			function and they take place synchronously inside _DoWork.
	*/
	extern void IoTHubClient_LL_DoWork(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle);

	/**
	* @brief	This API sets a runtime option identified by parameter @p optionName
	* 			to a value pointed to by @p value. @p optionName and the data type
	* 			@p value is pointing to are specific for every option.
	*
	* @param	iotHubClientHandle	The handle created by a call to the create function.
	* @param	optionName		  	Name of the option.
	* @param	value			  	The value.
	*
	*			The options that can be set via this API are:
	*				- @b timeout - the maximum time in milliseconds a communication is
	*				  allowed to use. @p value is a pointer to an @c unsigned @c int with
	*				  the timeout value in milliseconds. This is only supported for the HTTP
	*				  protocol as of now. When the HTTP protocol uses CURL, the meaning of
	*				  the parameter is <em>total request time</em>. When the HTTP protocol uses
	*				  winhttp, the meaning is the same as the @c dwSendTimeout and
	*				  @c dwReceiveTimeout parameters of the
	*				  <a href="https://msdn.microsoft.com/en-us/library/windows/desktop/aa384116(v=vs.85).aspx">
	*				  WinHttpSetTimeouts</a> API.
	*				- @b CURLOPT_LOW_SPEED_LIMIT - only available for HTTP protocol and only
	*				  when CURL is used. It has the same meaning as CURL's option with the same
	*				  name. @p value is pointer to a long.
	*				- @b CURLOPT_LOW_SPEED_TIME - only available for HTTP protocol and only
	*				  when CURL is used. It has the same meaning as CURL's option with the same
	*				  name. @p value is pointer to a long.
	*				- @b CURLOPT_FORBID_REUSE - only available for HTTP protocol and only
	*				  when CURL is used. It has the same meaning as CURL's option with the same
	*				  name. @p value is pointer to a long.
	*				- @b CURLOPT_FRESH_CONNECT - only available for HTTP protocol and only
	*				  when CURL is used. It has the same meaning as CURL's option with the same
	*				  name. @p value is pointer to a long.
	*				- @b CURLOPT_VERBOSE - only available for HTTP protocol and only
	*				  when CURL is used. It has the same meaning as CURL's option with the same
	*				  name. @p value is pointer to a long.
	*              - @b keepalive - available for MQTT protocol.  Integer value that sets the
	*                interval in seconds when pings are sent to the server.
	*              - @b logtrace - available for MQTT protocol.  Boolean value that turns on and
	*                off the diagnostic logging.
	*
	* @return	IOTHUB_CLIENT_OK upon success or an error code upon failure.
	*/
	extern IOTHUB_CLIENT_RESULT IoTHubClient_LL_SetOption(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle, const char* optionName, const void* value);

#ifndef DONT_USE_UPLOADTOBLOB
    /**
    * @brief	This API uploads to Azure Storage the content pointed to by @p source having the size @p size
    *           under the blob name devicename/@pdestinationFileName
    *
    * @param	iotHubClientHandle	    The handle created by a call to the create function.
    * @param	destinationFileName     name of the file.
    * @param	source                  pointer to the source for file content (can be NULL)
    * @param    size                    the size of the source in memory (if @p source is NULL then size needs to be 0).
    *
    * @return	IOTHUB_CLIENT_OK upon success or an error code upon failure.
    */
    extern IOTHUB_CLIENT_RESULT IoTHubClient_LL_UploadToBlob(IOTHUB_CLIENT_LL_HANDLE iotHubClientHandle, const char* destinationFileName, const unsigned char* source, size_t size);

#endif /*DONT_USE_UPLOADTOBLOB*/

#ifdef __cplusplus
}
#endif

#endif /* IOTHUB_CLIENT_LL_H */