myopcualearning/include/ua_connection.h
Wolfgang Hottgenroth da498bb161 * add include files and static library due to problems with AMALGAM'ED
distri and nodeset feature
* add UaModeler project including XML export
* add nodeset using test server
2016-06-08 11:21:06 +02:00

124 lines
4.7 KiB
C

/*
* Copyright (C) 2014-2016 the contributors as stated in the AUTHORS file
*
* This file is part of open62541. open62541 is free software: you can
* redistribute it and/or modify it under the terms of the GNU Lesser General
* Public License, version 3 (as published by the Free Software Foundation) with
* a static linking exception as stated in the LICENSE file provided with
* open62541.
*
* open62541 is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
* A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
* details.
*/
#ifndef UA_CONNECTION_H_
#define UA_CONNECTION_H_
#ifdef __cplusplus
extern "C" {
#endif
#include "ua_types.h"
/* Forward declarations */
struct UA_Connection;
typedef struct UA_Connection UA_Connection;
struct UA_SecureChannel;
typedef struct UA_SecureChannel UA_SecureChannel;
/**
* Networking
* ----------
* Client-server connection is represented by a `UA_Connection` structure. In
* order to allow for different operating systems and connection types. For
* this, `UA_Connection` stores a pointer to user-defined data and
* function-pointers to interact with the underlying networking implementation.
*
* An example networklayer for TCP communication is contained in the plugins
* folder. The networklayer forwards messages with `UA_Connection` structures to
* the main open62541 library. The library can then return messages vie TCP
* without being aware of the underlying transport technology.
*
* Connection Config
* ================= */
typedef struct UA_ConnectionConfig {
UA_UInt32 protocolVersion;
UA_UInt32 sendBufferSize;
UA_UInt32 recvBufferSize;
UA_UInt32 maxMessageSize;
UA_UInt32 maxChunkCount;
} UA_ConnectionConfig;
extern const UA_EXPORT UA_ConnectionConfig UA_ConnectionConfig_standard;
/**
* Connection Structure
* ==================== */
typedef enum UA_ConnectionState {
UA_CONNECTION_OPENING, /* The socket is open, but the HEL/ACK handshake
is not done */
UA_CONNECTION_ESTABLISHED, /* The socket is open and the connection
configured */
UA_CONNECTION_CLOSED, /* The socket has been closed and the connection
will be deleted */
} UA_ConnectionState;
struct UA_Connection {
UA_ConnectionState state;
UA_ConnectionConfig localConf;
UA_ConnectionConfig remoteConf;
UA_SecureChannel *channel; /* The securechannel that is attached to
this connection */
UA_Int32 sockfd; /* Most connectivity solutions run on
sockets. Having the socket id here
simplifies the design. */
void *handle; /* A pointer to the networklayer */
UA_ByteString incompleteMessage; /* A half-received message (TCP is a
streaming protocol) is stored here */
/* Get a buffer for sending */
UA_StatusCode (*getSendBuffer)(UA_Connection *connection, size_t length,
UA_ByteString *buf);
/* Release the send buffer manually */
void (*releaseSendBuffer)(UA_Connection *connection, UA_ByteString *buf);
/* Sends a message over the connection. The message buffer is always freed,
* even if sending fails.
*
* @param connection The connection
* @param buf The message buffer
* @return Returns an error code or UA_STATUSCODE_GOOD. */
UA_StatusCode (*send)(UA_Connection *connection, UA_ByteString *buf);
/* Receive a message from the remote connection
*
* @param connection The connection
* @param response The response string. It is allocated by the connection
* and needs to be freed with connection->releaseBuffer
* @param timeout Timeout of the recv operation in milliseconds
* @return Returns UA_STATUSCODE_BADCOMMUNICATIONERROR if the recv operation
* can be repeated, UA_STATUSCODE_GOOD if it succeeded and
* UA_STATUSCODE_BADCONNECTIONCLOSED if the connection was
* closed. */
UA_StatusCode (*recv)(UA_Connection *connection, UA_ByteString *response, UA_UInt32 timeout);
/* Release the buffer of a received message */
void (*releaseRecvBuffer)(UA_Connection *connection, UA_ByteString *buf);
/* Close the connection */
void (*close)(UA_Connection *connection);
};
void UA_EXPORT UA_Connection_init(UA_Connection *connection);
void UA_EXPORT UA_Connection_deleteMembers(UA_Connection *connection);
#ifdef __cplusplus
} // extern "C"
#endif
#endif /* UA_CONNECTION_H_ */