DL_DataGetFromUniqueRecordId
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SYNOPSIS
# include <cssm.h>
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PARAMETERS
| DLDBHandle (input) | ||
The handle pair that describes the add-in data storage library module to be used to perform this function and the open data store to search for the data record. | ||
| UniqueRecord (input) | ||
The pointer to a unique record structure returned from a DL_DataInsert, DL_DataGetFirst, or DL_DataGetNext operation. | ||
| Attributes (optional-input/output) | ||
If the Attributes structure pointer is NULL, no values are returned. Otherwise, the DataRecordType, NumberOfAttributes and AttributeData fields are read. AttributeData must be an array of NumberOfAttributes CSSM_DB_RECORD_ATTRIBUTE elements. Only the Info field of each element is used on input. The AttributeFormat field of the Info field is ignored on input. On output, a CSSM_DB_RECORD_ATTRIBUTE structure containing a list of all or the requested attribute values (subset) from the retrieved record. The SemanticInformation field is set. For each CSSM_DB_ATTRIBUTE_DATA contained in the AttributeData array, the NumberOfValues field is set to reflect the size of the Value array which is allocated by the DL using the application specified allocators. Each CSSM_DATA in the Value array will have it's Data field as a pointer to data allocated using the application specified allocators containing the attributes value, and have it's Length set to the length of the value. All values for an attribute are returned (this could be 0). All fields in the Info field of the CSSM_DB_ATTRIBUTE_DATA are left unchanged except for the AttributeFormat field, which is set to reflect the schema. | ||
| Data (optional-input/output) | ||
Data values contained in the referenced memory are ignored during processing and are overwritten with the retrieved opaque object. On output, a CSSM_DATA structure containing the opaque object stored in the retrieved record. If the pointer is data structure pointer is NULL, the opaque object is not returned. | ||
DESCRIPTION
This function retrieves the data record and attributes associated with this unique record identifier. The Attributes parameter can specify a subset of the attributes to be returned. If Attributes specifies an attribute that is not defined in the database's meta-information, an error condition is returned. The output buffers for the retrieved record are allocated by this function using the memory management functions provided during the module attach operation. The DL module can use an indexing structure identified in the UniqueRecordId to enhance the performance of the retrieval operation.
The DL should assume that the value of CSSM_QUERY_FLAGS is when performing this operation. In particular this means that if the data of a key record is being retrieved, the DL will return a CSSM_KEY structure with a key reference.
If the record referenced by UniqueRecordIdentifier has been modified since the last time it was retrieved, the error (warning) CSSMERR_DL_RECORD_MODIFIED is returned but the requested attributes and data of the new record is returned. The caller should be advised that other attributes (or the data) might have changed that were not fetched from the DL with this call.
RETURN VALUE
A CSSM_RETURN value indicating success or specifying a particular error condition. The value CSSM_OK indicates success. All other values represent an error condition.