function lfds700_queue_query

Source Files

└───liblfds700
    ├───inc
    │   └───liblfds700
    │           lfds700_queue.h
    └───src
        └───lfds700_queue
                lfds700_queue_query.c

Enums

enum lfds700_queue_query
{
  LFDS700_QUEUE_QUERY_SINGLETHREADED_GET_COUNT,
  LFDS700_QUEUE_QUERY_SINGLETHREADED_VALIDATE
};

Opaque Structures

struct lfds700_queue_state;

Prototype

void lfds700_queue_query( struct lfds700_queue_state *qs,
                          enum lfds700_queue_query query_type,
                          void *query_input,
                          void *query_output );

Parameters

struct lfds700_queue_state *qs

A pointer to an initialized struct lfds700_queue_state.

enum lfds700_queue_query query_type

Indicates which query to perform.

void *query_input

A pointer to data, or data cast to a void pointer, which is input data required by query indicated by query_type.

void *query_output

A pointer to store into which the requested information is placed, where the output data varies by the query indicted by query_type.

Queries

void *query_input

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

LFDS700_QUEUE_QUERY_SINGLETHREADED_GET_COUNT

query_input is NULL.

LFDS700_QUEUE_QUERY_SINGLETHREADED_VALIDATE

query_input can be NULL, or or can be a pointer to a struct lfds700_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;

LFDS700_QUEUE_QUERY_SINGLETHREADED_GET_COUNT

Points to a lfds700_pal_uint_t, which is set to the number of elements in the queue.

LFDS700_QUEUE_QUERY_SINGLETHREADED_VALIDATE

Points to an enum lfds700_misc_validity, which is set to indicate the result of the validation operation.

Notes

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

Example

Coming soon. No, really! (Written 29th Dec 2015).

See Also

• Queue