[13]open62541v1.2 official documents in Chinese_ Internals 1

brief introduction

When writing an application, it is more comfortable to use some GUI tools to create an information model. Most tools can export data according to OPC UA Nodeset XML schema. open62541 includes a python based nodeset compiler, which can transform these information model definitions into a working server.

Note that you can use tools / nodeset_ The nodeset compiler found in the compiler subfolder is not an XML conversion tool, but a compiler. This means that it will create an internal representation when parsing the XML file and try to understand and verify the correctness of the representation in order to generate C code.

target

Translation and supplement open62541v1 2 official manual.

Status code

Status codes are widely used in OPC UA protocol and open62541 API. They are made up of StatusCode Data type representation. The following definitions are OPC provided from OPC UA standard Ua. StatusCodes. Automatically generated in CSV file.

/* These StatusCodes are manually generated. */
#define UA_STATUSCODE_GOOD 0x00
#define UA_STATUSCODE_INFOTYPE_DATAVALUE 0x00000400
#define UA_STATUSCODE_INFOBITS_OVERFLOW 0x00000080

/* An unexpected error occurred. */
#define UA_STATUSCODE_BADUNEXPECTEDERROR 0x80010000

/* An internal error occurred as a result of a programming or configuration error. */
#define UA_STATUSCODE_BADINTERNALERROR 0x80020000

/* Not enough memory to complete the operation. */
#define UA_STATUSCODE_BADOUTOFMEMORY 0x80030000

/* An operating system resource is not available. */
#define UA_STATUSCODE_BADRESOURCEUNAVAILABLE 0x80040000

/* A low level communication error occurred. */
#define UA_STATUSCODE_BADCOMMUNICATIONERROR 0x80050000

/* Encoding halted because of invalid data in the objects being serialized. */
#define UA_STATUSCODE_BADENCODINGERROR 0x80060000

/* Decoding halted because of invalid data in the stream. */
#define UA_STATUSCODE_BADDECODINGERROR 0x80070000

/* The message encoding/decoding limits imposed by the stack have been exceeded. */
#define UA_STATUSCODE_BADENCODINGLIMITSEXCEEDED 0x80080000

/* The request message size exceeds limits set by the server. */
#define UA_STATUSCODE_BADREQUESTTOOLARGE 0x80B80000

/* The response message size exceeds limits set by the client. */
#define UA_STATUSCODE_BADRESPONSETOOLARGE 0x80B90000

/* An unrecognized response was received from the server. */
#define UA_STATUSCODE_BADUNKNOWNRESPONSE 0x80090000

/* The operation timed out. */
#define UA_STATUSCODE_BADTIMEOUT 0x800A0000

/* The server does not support the requested service. */
#define UA_STATUSCODE_BADSERVICEUNSUPPORTED 0x800B0000

/* The operation was cancelled because the application is shutting down. */
#define UA_STATUSCODE_BADSHUTDOWN 0x800C0000

/* The operation could not complete because the client is not connected to the server. */
#define UA_STATUSCODE_BADSERVERNOTCONNECTED 0x800D0000

/* The server has stopped and cannot process any requests. */
#define UA_STATUSCODE_BADSERVERHALTED 0x800E0000

/* There was nothing to do because the client passed a list of operations with no elements. */
#define UA_STATUSCODE_BADNOTHINGTODO 0x800F0000

/* The request could not be processed because it specified too many operations. */
#define UA_STATUSCODE_BADTOOMANYOPERATIONS 0x80100000

/* The request could not be processed because there are too many monitored items in the subscription. */
#define UA_STATUSCODE_BADTOOMANYMONITOREDITEMS 0x80DB0000

/* The extension object cannot be (de)serialized because the data type id is not recognized. */
#define UA_STATUSCODE_BADDATATYPEIDUNKNOWN 0x80110000

/* The certificate provided as a parameter is not valid. */
#define UA_STATUSCODE_BADCERTIFICATEINVALID 0x80120000

/* An error occurred verifying security. */
#define UA_STATUSCODE_BADSECURITYCHECKSFAILED 0x80130000

/* The certificate does not meet the requirements of the security policy. */
#define UA_STATUSCODE_BADCERTIFICATEPOLICYCHECKFAILED 0x81140000

/* The certificate has expired or is not yet valid. */
#define UA_STATUSCODE_BADCERTIFICATETIMEINVALID 0x80140000

/* An issuer certificate has expired or is not yet valid. */
#define UA_STATUSCODE_BADCERTIFICATEISSUERTIMEINVALID 0x80150000

/* The HostName used to connect to a server does not match a HostName in the certificate. */
#define UA_STATUSCODE_BADCERTIFICATEHOSTNAMEINVALID 0x80160000

/* The URI specified in the ApplicationDescription does not match the URI in the certificate. */
#define UA_STATUSCODE_BADCERTIFICATEURIINVALID 0x80170000

/* The certificate may not be used for the requested operation. */
#define UA_STATUSCODE_BADCERTIFICATEUSENOTALLOWED 0x80180000

/* The issuer certificate may not be used for the requested operation. */
#define UA_STATUSCODE_BADCERTIFICATEISSUERUSENOTALLOWED 0x80190000

/* The certificate is not trusted. */
#define UA_STATUSCODE_BADCERTIFICATEUNTRUSTED 0x801A0000

/* It was not possible to determine if the certificate has been revoked. */
#define UA_STATUSCODE_BADCERTIFICATEREVOCATIONUNKNOWN 0x801B0000

/* It was not possible to determine if the issuer certificate has been revoked. */
#define UA_STATUSCODE_BADCERTIFICATEISSUERREVOCATIONUNKNOWN 0x801C0000

/* The certificate has been revoked. */
#define UA_STATUSCODE_BADCERTIFICATEREVOKED 0x801D0000

/* The issuer certificate has been revoked. */
#define UA_STATUSCODE_BADCERTIFICATEISSUERREVOKED 0x801E0000

/* The certificate chain is incomplete. */
#define UA_STATUSCODE_BADCERTIFICATECHAININCOMPLETE 0x810D0000

/* User does not have permission to perform the requested operation. */
#define UA_STATUSCODE_BADUSERACCESSDENIED 0x801F0000

/* The user identity token is not valid. */
#define UA_STATUSCODE_BADIDENTITYTOKENINVALID 0x80200000

/* The user identity token is valid but the server has rejected it. */
#define UA_STATUSCODE_BADIDENTITYTOKENREJECTED 0x80210000

/* The specified secure channel is no longer valid. */
#define UA_STATUSCODE_BADSECURECHANNELIDINVALID 0x80220000

/* The timestamp is outside the range allowed by the server. */
#define UA_STATUSCODE_BADINVALIDTIMESTAMP 0x80230000

/* The nonce does appear to be not a random value or it is not the correct length. */
#define UA_STATUSCODE_BADNONCEINVALID 0x80240000

/* The session id is not valid. */
#define UA_STATUSCODE_BADSESSIONIDINVALID 0x80250000

/* The session was closed by the client. */
#define UA_STATUSCODE_BADSESSIONCLOSED 0x80260000

/* The session cannot be used because ActivateSession has not been called. */
#define UA_STATUSCODE_BADSESSIONNOTACTIVATED 0x80270000

/* The subscription id is not valid. */
#define UA_STATUSCODE_BADSUBSCRIPTIONIDINVALID 0x80280000

/* The header for the request is missing or invalid. */
#define UA_STATUSCODE_BADREQUESTHEADERINVALID 0x802A0000

/* The timestamps to return parameter is invalid. */
#define UA_STATUSCODE_BADTIMESTAMPSTORETURNINVALID 0x802B0000

/* The request was cancelled by the client. */
#define UA_STATUSCODE_BADREQUESTCANCELLEDBYCLIENT 0x802C0000

/* Too many arguments were provided. */
#define UA_STATUSCODE_BADTOOMANYARGUMENTS 0x80E50000

/* The server requires a license to operate in general or to perform a service or operation */
#define UA_STATUSCODE_BADLICENSEEXPIRED 0x810E0000

/* The server has limits on number of allowed operations / objects */
#define UA_STATUSCODE_BADLICENSELIMITSEXCEEDED 0x810F0000

/* The server does not have a license which is required to operate in general or to perform a service or operation. */
#define UA_STATUSCODE_BADLICENSENOTAVAILABLE 0x81100000

/* The subscription was transferred to another session. */
#define UA_STATUSCODE_GOODSUBSCRIPTIONTRANSFERRED 0x002D0000

/* The processing will complete asynchronously. */
#define UA_STATUSCODE_GOODCOMPLETESASYNCHRONOUSLY 0x002E0000

/* Sampling has slowed down due to resource limitations. */
#define UA_STATUSCODE_GOODOVERLOAD 0x002F0000

/* The value written was accepted but was clamped. */
#define UA_STATUSCODE_GOODCLAMPED 0x00300000

/* Communication with the data source is defined */
#define UA_STATUSCODE_BADNOCOMMUNICATION 0x80310000

/* Waiting for the server to obtain values from the underlying data source. */
#define UA_STATUSCODE_BADWAITINGFORINITIALDATA 0x80320000

/* The syntax of the node id is not valid. */
#define UA_STATUSCODE_BADNODEIDINVALID 0x80330000

/* The node id refers to a node that does not exist in the server address space. */
#define UA_STATUSCODE_BADNODEIDUNKNOWN 0x80340000

/* The attribute is not supported for the specified Node. */
#define UA_STATUSCODE_BADATTRIBUTEIDINVALID 0x80350000

/* The syntax of the index range parameter is invalid. */
#define UA_STATUSCODE_BADINDEXRANGEINVALID 0x80360000

/* No data exists within the range of indexes specified. */
#define UA_STATUSCODE_BADINDEXRANGENODATA 0x80370000

/* The data encoding is invalid. */
#define UA_STATUSCODE_BADDATAENCODINGINVALID 0x80380000

/* The server does not support the requested data encoding for the node. */
#define UA_STATUSCODE_BADDATAENCODINGUNSUPPORTED 0x80390000

/* The access level does not allow reading or subscribing to the Node. */
#define UA_STATUSCODE_BADNOTREADABLE 0x803A0000

/* The access level does not allow writing to the Node. */
#define UA_STATUSCODE_BADNOTWRITABLE 0x803B0000

/* The value was out of range. */
#define UA_STATUSCODE_BADOUTOFRANGE 0x803C0000

/* The requested operation is not supported. */
#define UA_STATUSCODE_BADNOTSUPPORTED 0x803D0000

/* A requested item was not found or a search operation ended without success. */
#define UA_STATUSCODE_BADNOTFOUND 0x803E0000

/* The object cannot be used because it has been deleted. */
#define UA_STATUSCODE_BADOBJECTDELETED 0x803F0000

/* Requested operation is not implemented. */
#define UA_STATUSCODE_BADNOTIMPLEMENTED 0x80400000

/* The monitoring mode is invalid. */
#define UA_STATUSCODE_BADMONITORINGMODEINVALID 0x80410000

/* The monitoring item id does not refer to a valid monitored item. */
#define UA_STATUSCODE_BADMONITOREDITEMIDINVALID 0x80420000

/* The monitored item filter parameter is not valid. */
#define UA_STATUSCODE_BADMONITOREDITEMFILTERINVALID 0x80430000

/* The server does not support the requested monitored item filter. */
#define UA_STATUSCODE_BADMONITOREDITEMFILTERUNSUPPORTED 0x80440000

/* A monitoring filter cannot be used in combination with the attribute specified. */
#define UA_STATUSCODE_BADFILTERNOTALLOWED 0x80450000

/* A mandatory structured parameter was missing or null. */
#define UA_STATUSCODE_BADSTRUCTUREMISSING 0x80460000

/* The event filter is not valid. */
#define UA_STATUSCODE_BADEVENTFILTERINVALID 0x80470000

/* The content filter is not valid. */
#define UA_STATUSCODE_BADCONTENTFILTERINVALID 0x80480000

/* An unrecognized operator was provided in a filter. */
#define UA_STATUSCODE_BADFILTEROPERATORINVALID 0x80C10000

/* A valid operator was provided */
#define UA_STATUSCODE_BADFILTEROPERATORUNSUPPORTED 0x80C20000

/* The number of operands provided for the filter operator was less then expected for the operand provided. */
#define UA_STATUSCODE_BADFILTEROPERANDCOUNTMISMATCH 0x80C30000

/* The operand used in a content filter is not valid. */
#define UA_STATUSCODE_BADFILTEROPERANDINVALID 0x80490000

/* The referenced element is not a valid element in the content filter. */
#define UA_STATUSCODE_BADFILTERELEMENTINVALID 0x80C40000

/* The referenced literal is not a valid value. */
#define UA_STATUSCODE_BADFILTERLITERALINVALID 0x80C50000

/* The continuation point provide is longer valid. */
#define UA_STATUSCODE_BADCONTINUATIONPOINTINVALID 0x804A0000

/* The operation could not be processed because all continuation points have been allocated. */
#define UA_STATUSCODE_BADNOCONTINUATIONPOINTS 0x804B0000

/* The reference type id does not refer to a valid reference type node. */
#define UA_STATUSCODE_BADREFERENCETYPEIDINVALID 0x804C0000

/* The browse direction is not valid. */
#define UA_STATUSCODE_BADBROWSEDIRECTIONINVALID 0x804D0000

/* The node is not part of the view. */
#define UA_STATUSCODE_BADNODENOTINVIEW 0x804E0000

/* The number was not accepted because of a numeric overflow. */
#define UA_STATUSCODE_BADNUMERICOVERFLOW 0x81120000

/* The ServerUri is not a valid URI. */
#define UA_STATUSCODE_BADSERVERURIINVALID 0x804F0000

/* No ServerName was specified. */
#define UA_STATUSCODE_BADSERVERNAMEMISSING 0x80500000

/* No DiscoveryUrl was specified. */
#define UA_STATUSCODE_BADDISCOVERYURLMISSING 0x80510000

/* The semaphore file specified by the client is not valid. */
#define UA_STATUSCODE_BADSEMPAHOREFILEMISSING 0x80520000

/* The security token request type is not valid. */
#define UA_STATUSCODE_BADREQUESTTYPEINVALID 0x80530000

/* The security mode does not meet the requirements set by the server. */
#define UA_STATUSCODE_BADSECURITYMODEREJECTED 0x80540000

/* The security policy does not meet the requirements set by the server. */
#define UA_STATUSCODE_BADSECURITYPOLICYREJECTED 0x80550000

/* The server has reached its maximum number of sessions. */
#define UA_STATUSCODE_BADTOOMANYSESSIONS 0x80560000

/* The user token signature is missing or invalid. */
#define UA_STATUSCODE_BADUSERSIGNATUREINVALID 0x80570000

/* The signature generated with the client certificate is missing or invalid. */
#define UA_STATUSCODE_BADAPPLICATIONSIGNATUREINVALID 0x80580000

/* The client did not provide at least one software certificate that is valid and meets the profile requirements for the server. */
#define UA_STATUSCODE_BADNOVALIDCERTIFICATES 0x80590000

/* The server does not support changing the user identity assigned to the session. */
#define UA_STATUSCODE_BADIDENTITYCHANGENOTSUPPORTED 0x80C60000

/* The request was cancelled by the client with the Cancel service. */
#define UA_STATUSCODE_BADREQUESTCANCELLEDBYREQUEST 0x805A0000

/* The parent node id does not to refer to a valid node. */
#define UA_STATUSCODE_BADPARENTNODEIDINVALID 0x805B0000

/* The reference could not be created because it violates constraints imposed by the data model. */
#define UA_STATUSCODE_BADREFERENCENOTALLOWED 0x805C0000

/* The requested node id was reject because it was either invalid or server does not allow node ids to be specified by the client. */
#define UA_STATUSCODE_BADNODEIDREJECTED 0x805D0000

/* The requested node id is already used by another node. */
#define UA_STATUSCODE_BADNODEIDEXISTS 0x805E0000

/* The node class is not valid. */
#define UA_STATUSCODE_BADNODECLASSINVALID 0x805F0000

/* The browse name is invalid. */
#define UA_STATUSCODE_BADBROWSENAMEINVALID 0x80600000

/* The browse name is not unique among nodes that share the same relationship with the parent. */
#define UA_STATUSCODE_BADBROWSENAMEDUPLICATED 0x80610000

/* The node attributes are not valid for the node class. */
#define UA_STATUSCODE_BADNODEATTRIBUTESINVALID 0x80620000

/* The type definition node id does not reference an appropriate type node. */
#define UA_STATUSCODE_BADTYPEDEFINITIONINVALID 0x80630000

/* The source node id does not reference a valid node. */
#define UA_STATUSCODE_BADSOURCENODEIDINVALID 0x80640000

/* The target node id does not reference a valid node. */
#define UA_STATUSCODE_BADTARGETNODEIDINVALID 0x80650000

/* The reference type between the nodes is already defined. */
#define UA_STATUSCODE_BADDUPLICATEREFERENCENOTALLOWED 0x80660000

/* The server does not allow this type of self reference on this node. */
#define UA_STATUSCODE_BADINVALIDSELFREFERENCE 0x80670000

/* The reference type is not valid for a reference to a remote server. */
#define UA_STATUSCODE_BADREFERENCELOCALONLY 0x80680000

/* The server will not allow the node to be deleted. */
#define UA_STATUSCODE_BADNODELETERIGHTS 0x80690000

/* The server was not able to delete all target references. */
#define UA_STATUSCODE_UNCERTAINREFERENCENOTDELETED 0x40BC0000

/* The server index is not valid. */
#define UA_STATUSCODE_BADSERVERINDEXINVALID 0x806A0000

/* The view id does not refer to a valid view node. */
#define UA_STATUSCODE_BADVIEWIDUNKNOWN 0x806B0000

/* The view timestamp is not available or not supported. */
#define UA_STATUSCODE_BADVIEWTIMESTAMPINVALID 0x80C90000

/* The view parameters are not consistent with each other. */
#define UA_STATUSCODE_BADVIEWPARAMETERMISMATCH 0x80CA0000

/* The view version is not available or not supported. */
#define UA_STATUSCODE_BADVIEWVERSIONINVALID 0x80CB0000

/* The list of references may not be complete because the underlying system is not available. */
#define UA_STATUSCODE_UNCERTAINNOTALLNODESAVAILABLE 0x40C00000

/* The server should have followed a reference to a node in a remote server but did not. The result set may be incomplete. */
#define UA_STATUSCODE_GOODRESULTSMAYBEINCOMPLETE 0x00BA0000

/* The provided Nodeid was not a type definition nodeid. */
#define UA_STATUSCODE_BADNOTTYPEDEFINITION 0x80C80000

/* One of the references to follow in the relative path references to a node in the address space in another server. */
#define UA_STATUSCODE_UNCERTAINREFERENCEOUTOFSERVER 0x406C0000

/* The requested operation has too many matches to return. */
#define UA_STATUSCODE_BADTOOMANYMATCHES 0x806D0000

/* The requested operation requires too many resources in the server. */
#define UA_STATUSCODE_BADQUERYTOOCOMPLEX 0x806E0000

/* The requested operation has no match to return. */
#define UA_STATUSCODE_BADNOMATCH 0x806F0000

/* The max age parameter is invalid. */
#define UA_STATUSCODE_BADMAXAGEINVALID 0x80700000

/* The operation is not permitted over the current secure channel. */
#define UA_STATUSCODE_BADSECURITYMODEINSUFFICIENT 0x80E60000

/* The history details parameter is not valid. */
#define UA_STATUSCODE_BADHISTORYOPERATIONINVALID 0x80710000

/* The server does not support the requested operation. */
#define UA_STATUSCODE_BADHISTORYOPERATIONUNSUPPORTED 0x80720000

/* The defined timestamp to return was invalid. */
#define UA_STATUSCODE_BADINVALIDTIMESTAMPARGUMENT 0x80BD0000

/* The server does not support writing the combination of value */
#define UA_STATUSCODE_BADWRITENOTSUPPORTED 0x80730000

/* The value supplied for the attribute is not of the same type as the attribute's value. */
#define UA_STATUSCODE_BADTYPEMISMATCH 0x80740000

/* The method id does not refer to a method for the specified object. */
#define UA_STATUSCODE_BADMETHODINVALID 0x80750000

/* The client did not specify all of the input arguments for the method. */
#define UA_STATUSCODE_BADARGUMENTSMISSING 0x80760000

/* The executable attribute does not allow the execution of the method. */
#define UA_STATUSCODE_BADNOTEXECUTABLE 0x81110000

/* The server has reached its maximum number of subscriptions. */
#define UA_STATUSCODE_BADTOOMANYSUBSCRIPTIONS 0x80770000

/* The server has reached the maximum number of queued publish requests. */
#define UA_STATUSCODE_BADTOOMANYPUBLISHREQUESTS 0x80780000

/* There is no subscription available for this session. */
#define UA_STATUSCODE_BADNOSUBSCRIPTION 0x80790000

/* The sequence number is unknown to the server. */
#define UA_STATUSCODE_BADSEQUENCENUMBERUNKNOWN 0x807A0000

/* The requested notification message is no longer available. */
#define UA_STATUSCODE_BADMESSAGENOTAVAILABLE 0x807B0000

/* The client of the current session does not support one or more Profiles that are necessary for the subscription. */
#define UA_STATUSCODE_BADINSUFFICIENTCLIENTPROFILE 0x807C0000

/* The sub-state machine is not currently active. */
#define UA_STATUSCODE_BADSTATENOTACTIVE 0x80BF0000

/* An equivalent rule already exists. */
#define UA_STATUSCODE_BADALREADYEXISTS 0x81150000

/* The server cannot process the request because it is too busy. */
#define UA_STATUSCODE_BADTCPSERVERTOOBUSY 0x807D0000

/* The type of the message specified in the header invalid. */
#define UA_STATUSCODE_BADTCPMESSAGETYPEINVALID 0x807E0000

/* The SecureChannelId and/or TokenId are not currently in use. */
#define UA_STATUSCODE_BADTCPSECURECHANNELUNKNOWN 0x807F0000

/* The size of the message specified in the header is too large. */
#define UA_STATUSCODE_BADTCPMESSAGETOOLARGE 0x80800000

/* There are not enough resources to process the request. */
#define UA_STATUSCODE_BADTCPNOTENOUGHRESOURCES 0x80810000

/* An internal error occurred. */
#define UA_STATUSCODE_BADTCPINTERNALERROR 0x80820000

/* The server does not recognize the QueryString specified. */
#define UA_STATUSCODE_BADTCPENDPOINTURLINVALID 0x80830000

/* The request could not be sent because of a network interruption. */
#define UA_STATUSCODE_BADREQUESTINTERRUPTED 0x80840000

/* Timeout occurred while processing the request. */
#define UA_STATUSCODE_BADREQUESTTIMEOUT 0x80850000

/* The secure channel has been closed. */
#define UA_STATUSCODE_BADSECURECHANNELCLOSED 0x80860000

/* The token has expired or is not recognized. */
#define UA_STATUSCODE_BADSECURECHANNELTOKENUNKNOWN 0x80870000

/* The sequence number is not valid. */
#define UA_STATUSCODE_BADSEQUENCENUMBERINVALID 0x80880000

/* The applications do not have compatible protocol versions. */
#define UA_STATUSCODE_BADPROTOCOLVERSIONUNSUPPORTED 0x80BE0000

/* There is a problem with the configuration that affects the usefulness of the value. */
#define UA_STATUSCODE_BADCONFIGURATIONERROR 0x80890000

/* The variable should receive its value from another variable */
#define UA_STATUSCODE_BADNOTCONNECTED 0x808A0000

/* There has been a failure in the device/data source that generates the value that has affected the value. */
#define UA_STATUSCODE_BADDEVICEFAILURE 0x808B0000

/* There has been a failure in the sensor from which the value is derived by the device/data source. */
#define UA_STATUSCODE_BADSENSORFAILURE 0x808C0000

/* The source of the data is not operational. */
#define UA_STATUSCODE_BADOUTOFSERVICE 0x808D0000

/* The deadband filter is not valid. */
#define UA_STATUSCODE_BADDEADBANDFILTERINVALID 0x808E0000

/* Communication to the data source has failed. The variable value is the last value that had a good quality. */
#define UA_STATUSCODE_UNCERTAINNOCOMMUNICATIONLASTUSABLEVALUE 0x408F0000

/* Whatever was updating this value has stopped doing so. */
#define UA_STATUSCODE_UNCERTAINLASTUSABLEVALUE 0x40900000

/* The value is an operational value that was manually overwritten. */
#define UA_STATUSCODE_UNCERTAINSUBSTITUTEVALUE 0x40910000

/* The value is an initial value for a variable that normally receives its value from another variable. */
#define UA_STATUSCODE_UNCERTAININITIALVALUE 0x40920000

/* The value is at one of the sensor limits. */
#define UA_STATUSCODE_UNCERTAINSENSORNOTACCURATE 0x40930000

/* The value is outside of the range of values defined for this parameter. */
#define UA_STATUSCODE_UNCERTAINENGINEERINGUNITSEXCEEDED 0x40940000

/* The value is derived from multiple sources and has less than the required number of Good sources. */
#define UA_STATUSCODE_UNCERTAINSUBNORMAL 0x40950000

/* The value has been overridden. */
#define UA_STATUSCODE_GOODLOCALOVERRIDE 0x00960000

/* This Condition refresh failed */
#define UA_STATUSCODE_BADREFRESHINPROGRESS 0x80970000

/* This condition has already been disabled. */
#define UA_STATUSCODE_BADCONDITIONALREADYDISABLED 0x80980000

/* This condition has already been enabled. */
#define UA_STATUSCODE_BADCONDITIONALREADYENABLED 0x80CC0000

/* Property not available */
#define UA_STATUSCODE_BADCONDITIONDISABLED 0x80990000

/* The specified event id is not recognized. */
#define UA_STATUSCODE_BADEVENTIDUNKNOWN 0x809A0000

/* The event cannot be acknowledged. */
#define UA_STATUSCODE_BADEVENTNOTACKNOWLEDGEABLE 0x80BB0000

/* The dialog condition is not active. */
#define UA_STATUSCODE_BADDIALOGNOTACTIVE 0x80CD0000

/* The response is not valid for the dialog. */
#define UA_STATUSCODE_BADDIALOGRESPONSEINVALID 0x80CE0000

/* The condition branch has already been acknowledged. */
#define UA_STATUSCODE_BADCONDITIONBRANCHALREADYACKED 0x80CF0000

/* The condition branch has already been confirmed. */
#define UA_STATUSCODE_BADCONDITIONBRANCHALREADYCONFIRMED 0x80D00000

/* The condition has already been shelved. */
#define UA_STATUSCODE_BADCONDITIONALREADYSHELVED 0x80D10000

/* The condition is not currently shelved. */
#define UA_STATUSCODE_BADCONDITIONNOTSHELVED 0x80D20000

/* The shelving time not within an acceptable range. */
#define UA_STATUSCODE_BADSHELVINGTIMEOUTOFRANGE 0x80D30000

/* No data exists for the requested time range or event filter. */
#define UA_STATUSCODE_BADNODATA 0x809B0000

/* No data found to provide upper or lower bound value. */
#define UA_STATUSCODE_BADBOUNDNOTFOUND 0x80D70000

/* The server cannot retrieve a bound for the variable. */
#define UA_STATUSCODE_BADBOUNDNOTSUPPORTED 0x80D80000

/* Data is missing due to collection started/stopped/lost. */
#define UA_STATUSCODE_BADDATALOST 0x809D0000

/* Expected data is unavailable for the requested time range due to an un-mounted volume */
#define UA_STATUSCODE_BADDATAUNAVAILABLE 0x809E0000

/* The data or event was not successfully inserted because a matching entry exists. */
#define UA_STATUSCODE_BADENTRYEXISTS 0x809F0000

/* The data or event was not successfully updated because no matching entry exists. */
#define UA_STATUSCODE_BADNOENTRYEXISTS 0x80A00000

/* The client requested history using a timestamp format the server does not support (i.e requested ServerTimestamp when server only supports SourceTimestamp). */
#define UA_STATUSCODE_BADTIMESTAMPNOTSUPPORTED 0x80A10000

/* The data or event was successfully inserted into the historical database. */
#define UA_STATUSCODE_GOODENTRYINSERTED 0x00A20000

/* The data or event field was successfully replaced in the historical database. */
#define UA_STATUSCODE_GOODENTRYREPLACED 0x00A30000

/* The value is derived from multiple values and has less than the required number of Good values. */
#define UA_STATUSCODE_UNCERTAINDATASUBNORMAL 0x40A40000

/* No data exists for the requested time range or event filter. */
#define UA_STATUSCODE_GOODNODATA 0x00A50000

/* The data or event field was successfully replaced in the historical database. */
#define UA_STATUSCODE_GOODMOREDATA 0x00A60000

/* The requested number of Aggregates does not match the requested number of NodeIds. */
#define UA_STATUSCODE_BADAGGREGATELISTMISMATCH 0x80D40000

/* The requested Aggregate is not support by the server. */
#define UA_STATUSCODE_BADAGGREGATENOTSUPPORTED 0x80D50000

/* The aggregate value could not be derived due to invalid data inputs. */
#define UA_STATUSCODE_BADAGGREGATEINVALIDINPUTS 0x80D60000

/* The aggregate configuration is not valid for specified node. */
#define UA_STATUSCODE_BADAGGREGATECONFIGURATIONREJECTED 0x80DA0000

/* The request specifies fields which are not valid for the EventType or cannot be saved by the historian. */
#define UA_STATUSCODE_GOODDATAIGNORED 0x00D90000

/* The request was rejected by the server because it did not meet the criteria set by the server. */
#define UA_STATUSCODE_BADREQUESTNOTALLOWED 0x80E40000

/* The request has not been processed by the server yet. */
#define UA_STATUSCODE_BADREQUESTNOTCOMPLETE 0x81130000

/* The value does not come from the real source and has been edited by the server. */
#define UA_STATUSCODE_GOODEDITED 0x00DC0000

/* There was an error in execution of these post-actions. */
#define UA_STATUSCODE_GOODPOSTACTIONFAILED 0x00DD0000

/* The related EngineeringUnit has been changed but the Variable Value is still provided based on the previous unit. */
#define UA_STATUSCODE_UNCERTAINDOMINANTVALUECHANGED 0x40DE0000

/* A dependent value has been changed but the change has not been applied to the device. */
#define UA_STATUSCODE_GOODDEPENDENTVALUECHANGED 0x00E00000

/* The related EngineeringUnit has been changed but this change has not been applied to the device. The Variable Value is still dependent on the previous unit but its status is currently Bad. */
#define UA_STATUSCODE_BADDOMINANTVALUECHANGED 0x80E10000

/* A dependent value has been changed but the change has not been applied to the device. The quality of the dominant variable is uncertain. */
#define UA_STATUSCODE_UNCERTAINDEPENDENTVALUECHANGED 0x40E20000

/* A dependent value has been changed but the change has not been applied to the device. The quality of the dominant variable is Bad. */
#define UA_STATUSCODE_BADDEPENDENTVALUECHANGED 0x80E30000

/* The communication layer has raised an event. */
#define UA_STATUSCODE_GOODCOMMUNICATIONEVENT 0x00A70000

/* The system is shutting down. */
#define UA_STATUSCODE_GOODSHUTDOWNEVENT 0x00A80000

/* The operation is not finished and needs to be called again. */
#define UA_STATUSCODE_GOODCALLAGAIN 0x00A90000

/* A non-critical timeout occurred. */
#define UA_STATUSCODE_GOODNONCRITICALTIMEOUT 0x00AA0000

/* One or more arguments are invalid. */
#define UA_STATUSCODE_BADINVALIDARGUMENT 0x80AB0000

/* Could not establish a network connection to remote server. */
#define UA_STATUSCODE_BADCONNECTIONREJECTED 0x80AC0000

/* The server has disconnected from the client. */
#define UA_STATUSCODE_BADDISCONNECT 0x80AD0000

/* The network connection has been closed. */
#define UA_STATUSCODE_BADCONNECTIONCLOSED 0x80AE0000

/* The operation cannot be completed because the object is closed */
#define UA_STATUSCODE_BADINVALIDSTATE 0x80AF0000

/* Cannot move beyond end of the stream. */
#define UA_STATUSCODE_BADENDOFSTREAM 0x80B00000

/* No data is currently available for reading from a non-blocking stream. */
#define UA_STATUSCODE_BADNODATAAVAILABLE 0x80B10000

/* The asynchronous operation is waiting for a response. */
#define UA_STATUSCODE_BADWAITINGFORRESPONSE 0x80B20000

/* The asynchronous operation was abandoned by the caller. */
#define UA_STATUSCODE_BADOPERATIONABANDONED 0x80B30000

/* The stream did not return all data requested (possibly because it is a non-blocking stream). */
#define UA_STATUSCODE_BADEXPECTEDSTREAMTOBLOCK 0x80B40000

/* Non blocking behaviour is required and the operation would block. */
#define UA_STATUSCODE_BADWOULDBLOCK 0x80B50000

/* A value had an invalid syntax. */
#define UA_STATUSCODE_BADSYNTAXERROR 0x80B60000

/* The operation could not be finished because all available connections are in use. */
#define UA_STATUSCODE_BADMAXCONNECTIONSREACHED 0x80B70000

#Network plug-in API

connect

Client server connection by UA_Connection indicates. The connection is stateful and stores partially received messages, and so on. In addition, the connection contains a function pointer to the underlying network implementation. An example of this is the send function. Therefore, the connection encapsulates all the required network functions. This allows users of embedded (or other foreign) systems to implement their own network plug-ins and have a clear interface with the main open62541 library.

typedef struct {
    UA_UInt32 protocolVersion;
    UA_UInt32 recvBufferSize;
    UA_UInt32 sendBufferSize;
    UA_UInt32 localMaxMessageSize;  /* (0 = unbounded) */
    UA_UInt32 remoteMaxMessageSize; /* (0 = unbounded) */
    UA_UInt32 localMaxChunkCount;   /* (0 = unbounded) */
    UA_UInt32 remoteMaxChunkCount;  /* (0 = unbounded) */
} UA_ConnectionConfig;

typedef enum {
    UA_CONNECTIONSTATE_CLOSED,     /* The socket has been closed and the connection
                                    * will be deleted */
    UA_CONNECTIONSTATE_OPENING,    /* The socket is open, but the HEL/ACK handshake
                                    * is not done */
    UA_CONNECTIONSTATE_ESTABLISHED /* The socket is open and the connection
                                    * configured */
} UA_ConnectionState;

struct UA_Connection {
    UA_ConnectionState state;
    UA_SecureChannel *channel;     /* The securechannel that is attached to
                                    * this connection */
    UA_SOCKET sockfd;              /* Most connectivity solutions run on
                                    * sockets. Having the socket id here
                                    * simplifies the design. */
    UA_DateTime openingDate;       /* The date the connection was created */
    void *handle;                  /* A pointer to internal data */

    /* 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. If this is empty, it will be
     *        allocated by the connection and needs to be freed with
     *        connection->releaseBuffer. If the response string is non-empty, it
     *        will be used as the receive buffer. If bytes are received, the
     *        length of the buffer is adjusted to match the length of the
     *        received bytes.
     * @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. The network layer closes the socket. This is picked
     * up during the next 'listen' and the connection is freed in the network
     * layer. */
    void (*close)(UA_Connection *connection);

    /* To be called only from within the server (and not the network layer).
     * Frees up the connection's memory. */
    void (*free)(UA_Connection *connection);
};

Server network layer

Two functions of the remote client, the binaryconnection and the removeprocess, are exposed. These functions are called by the server network layer.

The work of the server network layer is to listen on the TCP socket, accept a new connection, call the server with the received message, and send a signal to the server to close the connection.

The network layer is part of the server configuration. Therefore, if the examples provided are not suitable for their architecture, users can provide a custom implementation. The network layer is only called in the main loop of the server. Therefore, the network layer does not need to be thread safe. If the network layer receives a positive blocking listening duration, the main loop of the server will block until a message is received or the duration times out.

/* Process a binary message (TCP packet). The message can contain partial
 * chunks. (TCP is a streaming protocol and packets may be split/merge during
 * transport.) After processing, the message is freed with
 * connection->releaseRecvBuffer. */
void
UA_Server_processBinaryMessage(UA_Server *server, UA_Connection *connection,
                               UA_ByteString *message);

/* The server internally cleans up the connection and then calls
 * connection->free. */
void
UA_Server_removeConnection(UA_Server *server, UA_Connection *connection);

struct UA_ServerNetworkLayer {
    void *handle; /* Internal data */

    /* Points to external memory, i.e. handled by server or client */
    UA_NetworkStatistics *statistics;

    UA_String discoveryUrl;

    UA_ConnectionConfig localConnectionConfig;

    /* Start listening on the networklayer.
     *
     * @param nl The network layer
     * @return Returns UA_STATUSCODE_GOOD or an error code. */
    UA_StatusCode (*start)(UA_ServerNetworkLayer *nl, const UA_Logger *logger,
                           const UA_String *customHostname);

    /* Listen for new and closed connections and arriving packets. Calls
     * UA_Server_processBinaryMessage for the arriving packets. Closed
     * connections are picked up here and forwarded to
     * UA_Server_removeConnection where they are cleaned up and freed.
     *
     * @param nl The network layer
     * @param server The server for processing the incoming packets and for
     *               closing connections.
     * @param timeout The timeout during which an event must arrive in
     *                milliseconds
     * @return A statuscode for the status of the network layer. */
    UA_StatusCode (*listen)(UA_ServerNetworkLayer *nl, UA_Server *server,
                            UA_UInt16 timeout);

    /* Close the network socket and all open connections. Afterwards, the
     * network layer can be safely deleted.
     *
     * @param nl The network layer
     * @param server The server that processes the incoming packets and for
     *               closing connections before deleting them.
     * @return A statuscode for the status of the closing operation. */
    void (*stop)(UA_ServerNetworkLayer *nl, UA_Server *server);

    /* Deletes the network layer context. Call only after stopping. */
    void (*clear)(UA_ServerNetworkLayer *nl);
};

Client network layer

The client has only one single connection for sending and receiving binary information.

/* @param config the connection config for this client
 * @param endpointUrl to where to connect
 * @param timeout in ms until the connection try times out if remote not reachable
 * @param logger the logger to use */
typedef UA_Connection
(*UA_ConnectClientConnection)(UA_ConnectionConfig config, UA_String endpointUrl,
                              UA_UInt32 timeout, const UA_Logger *logger);

Access control plug-in API

The access control callback is used to verify the session and grant the corresponding access rights.

sessionId and sessionContext can both be NULL. This happens, for example, when a MonitoredItem (underlying subscription) is detached from its session but continues to run.

struct UA_AccessControl {
    void *context;
    void (*clear)(UA_AccessControl *ac);

    /* Supported login mechanisms. The server endpoints are created from here. */
    size_t userTokenPoliciesSize;
    UA_UserTokenPolicy *userTokenPolicies;

    /* Authenticate a session. The session context is attached to the session
     * and later passed into the node-based access control callbacks. The new
     * session is rejected if a StatusCode other than UA_STATUSCODE_GOOD is
     * returned. */
    UA_StatusCode (*activateSession)(UA_Server *server, UA_AccessControl *ac,
                                     const UA_EndpointDescription *endpointDescription,
                                     const UA_ByteString *secureChannelRemoteCertificate,
                                     const UA_NodeId *sessionId,
                                     const UA_ExtensionObject *userIdentityToken,
                                     void **sessionContext);

    /* Deauthenticate a session and cleanup */
    void (*closeSession)(UA_Server *server, UA_AccessControl *ac,
                         const UA_NodeId *sessionId, void *sessionContext);

    /* Access control for all nodes*/
    UA_UInt32 (*getUserRightsMask)(UA_Server *server, UA_AccessControl *ac,
                                   const UA_NodeId *sessionId, void *sessionContext,
                                   const UA_NodeId *nodeId, void *nodeContext);

    /* Additional access control for variable nodes */
    UA_Byte (*getUserAccessLevel)(UA_Server *server, UA_AccessControl *ac,
                                  const UA_NodeId *sessionId, void *sessionContext,
                                  const UA_NodeId *nodeId, void *nodeContext);

    /* Additional access control for method nodes */
    UA_Boolean (*getUserExecutable)(UA_Server *server, UA_AccessControl *ac,
                                    const UA_NodeId *sessionId, void *sessionContext,
                                    const UA_NodeId *methodId, void *methodContext);

    /* Additional access control for calling a method node in the context of a
     * specific object */
    UA_Boolean (*getUserExecutableOnObject)(UA_Server *server, UA_AccessControl *ac,
                                            const UA_NodeId *sessionId, void *sessionContext,
                                            const UA_NodeId *methodId, void *methodContext,
                                            const UA_NodeId *objectId, void *objectContext);

    /* Allow adding a node */
    UA_Boolean (*allowAddNode)(UA_Server *server, UA_AccessControl *ac,
                               const UA_NodeId *sessionId, void *sessionContext,
                               const UA_AddNodesItem *item);

    /* Allow adding a reference */
    UA_Boolean (*allowAddReference)(UA_Server *server, UA_AccessControl *ac,
                                    const UA_NodeId *sessionId, void *sessionContext,
                                    const UA_AddReferencesItem *item);

    /* Allow deleting a node */
    UA_Boolean (*allowDeleteNode)(UA_Server *server, UA_AccessControl *ac,
                                  const UA_NodeId *sessionId, void *sessionContext,
                                  const UA_DeleteNodesItem *item);

    /* Allow deleting a reference */
    UA_Boolean (*allowDeleteReference)(UA_Server *server, UA_AccessControl *ac,
                                       const UA_NodeId *sessionId, void *sessionContext,
                                       const UA_DeleteReferencesItem *item);

    /* Allow browsing a node */
    UA_Boolean (*allowBrowseNode)(UA_Server *server, UA_AccessControl *ac,
                                  const UA_NodeId *sessionId, void *sessionContext,
                                  const UA_NodeId *nodeId, void *nodeContext);

#ifdef UA_ENABLE_SUBSCRIPTIONS
    /* Allow transfer of a subscription to another session. The Server shall
     * validate that the Client of that Session is operating on behalf of the
     * same user */
    UA_Boolean (*allowTransferSubscription)(UA_Server *server, UA_AccessControl *ac,
                                            const UA_NodeId *oldSessionId, void *oldSessionContext,
                                            const UA_NodeId *newSessionId, void *newSessionContext);
#endif

#ifdef UA_ENABLE_HISTORIZING
    /* Allow insert,replace,update of historical data */
    UA_Boolean (*allowHistoryUpdateUpdateData)(UA_Server *server, UA_AccessControl *ac,
                                               const UA_NodeId *sessionId, void *sessionContext,
                                               const UA_NodeId *nodeId,
                                               UA_PerformUpdateType performInsertReplace,
                                               const UA_DataValue *value);

    /* Allow delete of historical data */
    UA_Boolean (*allowHistoryUpdateDeleteRawModified)(UA_Server *server, UA_AccessControl *ac,
                                                      const UA_NodeId *sessionId, void *sessionContext,
                                                      const UA_NodeId *nodeId,
                                                      UA_DateTime startTimestamp,
                                                      UA_DateTime endTimestamp,
                                                      bool isDeleteModified);
#endif
};

Record plug-in API

The server and client define a logger in their configuration. The logger is a plug-in. As an example, we provide a default plug-in that logs to stdout. The logger plug-in is stateful and can point to custom data. So you can keep open file handlers in the context of the logger.

Each log information consists of a log level, a log category and a string information content. The timestamp of the log message is created in the logger.

typedef enum {
    UA_LOGLEVEL_TRACE = 0,
    UA_LOGLEVEL_DEBUG,
    UA_LOGLEVEL_INFO,
    UA_LOGLEVEL_WARNING,
    UA_LOGLEVEL_ERROR,
    UA_LOGLEVEL_FATAL
} UA_LogLevel;

typedef enum {
    UA_LOGCATEGORY_NETWORK = 0,
    UA_LOGCATEGORY_SECURECHANNEL,
    UA_LOGCATEGORY_SESSION,
    UA_LOGCATEGORY_SERVER,
    UA_LOGCATEGORY_CLIENT,
    UA_LOGCATEGORY_USERLAND,
    UA_LOGCATEGORY_SECURITYPOLICY
} UA_LogCategory;

typedef struct {
    /* Log a message. The message string and following varargs are formatted
     * according to the rules of the printf command. Use the convenience macros
     * below that take the minimum log-level defined in ua_config.h into
     * account. */
    void (*log)(void *logContext, UA_LogLevel level, UA_LogCategory category,
                const char *msg, va_list args);

    void *context; /* Logger state */

    void (*clear)(void *context); /* Clean up the logger plugin */
} UA_Logger;

static UA_INLINE UA_FORMAT(3,4) void
UA_LOG_TRACE(const UA_Logger *logger, UA_LogCategory category, const char *msg, ...) {
#if UA_LOGLEVEL <= 100
    if(!logger || !logger->log)
        return;
    va_list args; va_start(args, msg);
    logger->log(logger->context, UA_LOGLEVEL_TRACE, category, msg, args);
    va_end(args);
#else
    (void) logger;
    (void) category;
    (void) msg;
#endif
}

static UA_INLINE UA_FORMAT(3,4) void
UA_LOG_DEBUG(const UA_Logger *logger, UA_LogCategory category, const char *msg, ...) {
#if UA_LOGLEVEL <= 200
    if(!logger || !logger->log)
        return;
    va_list args; va_start(args, msg);
    logger->log(logger->context, UA_LOGLEVEL_DEBUG, category, msg, args);
    va_end(args);
#else
    (void) logger;
    (void) category;
    (void) msg;
#endif
}

static UA_INLINE UA_FORMAT(3,4) void
UA_LOG_INFO(const UA_Logger *logger, UA_LogCategory category, const char *msg, ...) {
#if UA_LOGLEVEL <= 300
    if(!logger || !logger->log)
        return;
    va_list args; va_start(args, msg);
    logger->log(logger->context, UA_LOGLEVEL_INFO, category, msg, args);
    va_end(args);
#else
    (void) logger;
    (void) category;
    (void) msg;
#endif
}

static UA_INLINE UA_FORMAT(3,4) void
UA_LOG_WARNING(const UA_Logger *logger, UA_LogCategory category, const char *msg, ...) {
#if UA_LOGLEVEL <= 400
    if(!logger || !logger->log)
        return;
    va_list args; va_start(args, msg);
    logger->log(logger->context, UA_LOGLEVEL_WARNING, category, msg, args);
    va_end(args);
#else
    (void) logger;
    (void) category;
    (void) msg;
#endif
}

static UA_INLINE UA_FORMAT(3,4) void
UA_LOG_ERROR(const UA_Logger *logger, UA_LogCategory category, const char *msg, ...) {
#if UA_LOGLEVEL <= 500
    if(!logger || !logger->log)
        return;
    va_list args; va_start(args, msg);
    logger->log(logger->context, UA_LOGLEVEL_ERROR, category, msg, args);
    va_end(args);
#else
    (void) logger;
    (void) category;
    (void) msg;
#endif
}

static UA_INLINE UA_FORMAT(3,4) void
UA_LOG_FATAL(const UA_Logger *logger, UA_LogCategory category, const char *msg, ...) {
#if UA_LOGLEVEL <= 600
    if(!logger || !logger->log)
        return;
    va_list args; va_start(args, msg);
    logger->log(logger->context, UA_LOGLEVEL_FATAL, category, msg, args);
    va_end(args);
#else
    (void) logger;
    (void) category;
    (void) msg;
#endif
}

PubSub connection plug-in API

PubSub connection API is the interface between specific network implementation and internal PubSub code.

The PubSub specification can create new connections at run time. wording. Connect - > OPC UA standard "high-level" perspective, and Channel - > open62541 implements "low-level" perspective. A channel can be assigned to different network implementations, such as UDP, MQTT and AMQP. This channel provides basic services, such as sending, registering, unregistering, receiving and closing.

struct UA_PubSubConnectionConfig;
typedef struct UA_PubSubConnectionConfig UA_PubSubConnectionConfig;

struct UA_PubSubChannel;
typedef struct UA_PubSubChannel UA_PubSubChannel;

typedef enum {
    UA_PUBSUB_CHANNEL_RDY,
    UA_PUBSUB_CHANNEL_PUB,
    UA_PUBSUB_CHANNEL_SUB,
    UA_PUBSUB_CHANNEL_PUB_SUB,
    UA_PUBSUB_CHANNEL_ERROR,
    UA_PUBSUB_CHANNEL_CLOSED
} UA_PubSubChannelState;

/* Interface structure between network plugin and internal implementation */
struct UA_PubSubChannel {
    UA_UInt32 publisherId; /* unique identifier */
    UA_PubSubChannelState state;
    UA_PubSubConnectionConfig *connectionConfig; /* link to parent connection config */
    UA_SOCKET sockfd;
    void *handle; /* implementation specific data */
    /*@info for handle: each network implementation should provide an structure
    * UA_PubSubChannelData[ImplementationName] This structure can be used by the
    * network implementation to store network implementation specific data.*/

    /* Sending out the content of the buf parameter */
    UA_StatusCode (*send)(UA_PubSubChannel *channel, UA_ExtensionObject *transportSettings,
                          const UA_ByteString *buf);

    /* Register to an specified message source, e.g. multicast group or topic. Callback is used for mqtt. */
    UA_StatusCode (*regist)(UA_PubSubChannel * channel, UA_ExtensionObject *transportSettings,
        void (*callback)(UA_ByteString *encodedBuffer, UA_ByteString *topic));

    /* Remove subscription to an specified message source, e.g. multicast group or topic */
    UA_StatusCode (*unregist)(UA_PubSubChannel * channel, UA_ExtensionObject *transportSettings);

    /* Receive messages. A regist to the message source is needed before. */
    UA_StatusCode (*receive)(UA_PubSubChannel * channel, UA_ByteString *,
                             UA_ExtensionObject *transportSettings, UA_UInt32 timeout);

    /* Closing the connection and implicit free of the channel structures. */
    UA_StatusCode (*close)(UA_PubSubChannel *channel);

    /* Giving the connection protocoll time to process inbound and outbound traffic. */
    UA_StatusCode (*yield)(UA_PubSubChannel *channel, UA_UInt16 timeout);
};

UA_PubSubTransportLayer is used to create a new connection. Whenever the runtime requests a new connection, the internal PubSub implementation calls the *'createPubSubChannel 'function. transportProfileUri "contains standard defined transport profile information to identify the connection types that can be created by TransportLayer. The server configuration contains a list of ua_pubsubsupportlayer. Take a look at tutorial_pubsub_connection for information about TransportLayer processing.

typedef struct {
    UA_String transportProfileUri;
    UA_PubSubChannel *(*createPubSubChannel)(UA_PubSubConnectionConfig *connectionConfig);
} UA_PubSubTransportLayer;

#endif /* UA_ENABLE_PUBSUB */

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Keywords: IoT ARM MCU

Added by ClarkF1 on Sat, 15 Jan 2022 00:20:58 +0200