function lfds710_hash_a_query

Source Files

└───liblfds710
    ├───inc
    │   └───liblfds710
    │           lfds710_hash_addonly.h
    └───src
        └───lfds710_hash_addonly
                lfds710_hash_addonly_query.c

Enums

enum lfds710_hash_a_query
{
  LFDS710_HASH_A_QUERY_GET_POTENTIALLY_INACCURATE_COUNT,
  LFDS710_HASH_A_QUERY_SINGLETHREADED_VALIDATE
};

Opaque Structures

struct lfds710_hash_a_state;

Prototype

void lfds710_hash_a_query( struct lfds710_hash_a_state *has,
                           enum lfds710_hash_a_query query_type,
                           void *query_input,
                           void *query_output );

Parameters

struct lfds710_hash_a_state *has

A pointer to an initialized struct lfds710_hash_a_state.

enum lfds710_hash_a_query query_type

Indicates which query to perform.

void *query_input

A pointer to input data for the query, where the data varies by query;

LFDS710_HASH_A_QUERY_GET_POTENTIALLY_INACCURATE_COUNT

query_input is NULL.

LFDS710_HASH_A_QUERY_SINGLETHREADED_VALIDATE

query_input can be NULL, or or can be a pointer to a struct lfds710_misc_validation_info, which specifies an expected min/max count, in which case validation also counts the number of elements and check they fall within the specified range.

void *query_output

A pointer to output store for the query, where the output varies by query;

LFDS710_HASH_A_QUERY_GET_POTENTIALLY_INACCURATE_COUNT

Points to a lfds710_pal_uint_t, which is set to the number of elements in the hash.

LFDS710_HASH_A_QUERY_SINGLETHREADED_VALIDATE

Points to an enum lfds710_misc_validity, which is set to indicate the result of the validation operation.

Notes

All SINGLETHREADED queries can only be safely performed if no insert operations occur while the operation runs. If insert operations do occur during the execution of a SINGLETHREADED query, it is theoretically possible for the query to enter an infinite loop or to access random memory. Do not do this.

The LFDS710_HASH_A_QUERY_GET_POTENTIALLY_INACCURATE_COUNT query is non-atomic and walks the trees which comprise the hash, counting elements; if new element are added during the count walks, they may not be seen. As such, the count is potentially inaccurate.

See Also

• Hash (add-only)