tarsnap/lib/datastruct/rwhashtab.h

#ifndef RWHASHTAB_H_
#define RWHASHTAB_H_

#include <stddef.h>	/* size_t */
#include <stdint.h>	/* uint8_t */

/**
 * Structure used to store RW hash table state.
 */
typedef struct rwhashtab_internal RWHASHTAB;

/**
 * rwhashtab_init(keyoffset, keylength):
 * Create an empty hash ${table} for storing records which contain keys of
 * length ${keylength} bytes starting at offset ${keyoffset} from the start
 * of each record.  Return NULL on failure.
 */
RWHASHTAB * rwhashtab_init(size_t, size_t);

/**
 * rwhashtab_getsize(table):
 * Return the number of entries in the ${table}.
 */
size_t rwhashtab_getsize(RWHASHTAB *);

/**
 * rwhashtab_insert(table, record):
 * Insert the provided ${record} into the hash ${table}.  Return (-1) on error,
 * 0 on success, and 1 if the table already contains a record with the same
 * key.
 */
int rwhashtab_insert(RWHASHTAB *, void *);

/**
 * rwhashtab_read(table, key):
 * Return a pointer to the record in the ${table} with the specified ${key}, or
 * NULL if no such record exists.
 */
void * rwhashtab_read(RWHASHTAB *, const uint8_t *);

/**
 * rwhashtab_foreach(table, func, cookie):
 * Call ${func(record, cookie)} for each ${record} in the hash ${table}.  Stop
 * the iteration early if ${func} returns a non-zero value; return 0 or the
 * non-zero value returned by ${func}.
 */
int rwhashtab_foreach(RWHASHTAB *, int(void *, void *), void *);

/**
 * rwhashtab_free(table):
 * Free the hash ${table}.
 */
void rwhashtab_free(RWHASHTAB *);

#endif /* !RWHASHTAB_H_ */