spv.h

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/*
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/**
 * @file spv.h
 * @brief Sparse Vector API
 *
 * This is a trimmed down sparse vector implementation tuned to the problem of
 * 24-bit FC_IDs. In this case, the 24-bit index value is broken down in three
 * 8-bit values. These values are used to index up to three 256 element arrays.
 * Arrays are allocated, only when needed. @n @n
 * The lookup can complete in constant time (3 indexed array references). @n @n
 * A typical use case would be that the fabric/directory FC_IDs would cause two rows to be
 * allocated, and the fabric assigned remote nodes would cause two rows to be allocated, with
 * the root row always allocated. This gives five rows of 256 x sizeof(void*),
 * resulting in 10k.
 */


#if !defined(__SPV_H__)
#define __SPV_H__

#define SPV_ROWLEN  256
#define SPV_DIM     3


/*!
* @defgroup spv Sparse Vector
*/

/**
 * @brief Sparse vector structure.
 */
typedef struct sparse_vector_s {
    ocs_os_handle_t os;
    uint32_t max_idx;       /**< maximum index value */
    void **array;           /**< pointer to 3D array */
} *sparse_vector_t;

extern void spv_del(sparse_vector_t spv);
extern sparse_vector_t spv_new(ocs_os_handle_t os);
extern void spv_set(sparse_vector_t sv, uint32_t idx, void *value);
extern void *spv_get(sparse_vector_t sv, uint32_t idx);

#endif // __SPV_H__