tor/src/or/fp_pair.c

300 lines
6.5 KiB
C

/* Copyright (c) 2013-2015, The Tor Project, Inc. */
/* See LICENSE for licensing information */
#include "or.h"
#include "fp_pair.h"
/* Define fp_pair_map_t structures */
struct fp_pair_map_entry_s {
HT_ENTRY(fp_pair_map_entry_s) node;
void *val;
fp_pair_t key;
};
struct fp_pair_map_s {
HT_HEAD(fp_pair_map_impl, fp_pair_map_entry_s) head;
};
/*
* Hash function and equality checker for fp_pair_map_t
*/
/** Compare fp_pair_entry_t objects by key value. */
static INLINE int
fp_pair_map_entries_eq(const fp_pair_map_entry_t *a,
const fp_pair_map_entry_t *b)
{
return tor_memeq(&(a->key), &(b->key), sizeof(fp_pair_t));
}
/** Return a hash value for an fp_pair_entry_t. */
static INLINE unsigned int
fp_pair_map_entry_hash(const fp_pair_map_entry_t *a)
{
tor_assert(sizeof(a->key) == DIGEST_LEN*2);
return (unsigned) siphash24g(&a->key, DIGEST_LEN*2);
}
/*
* Hash table functions for fp_pair_map_t
*/
HT_PROTOTYPE(fp_pair_map_impl, fp_pair_map_entry_s, node,
fp_pair_map_entry_hash, fp_pair_map_entries_eq)
HT_GENERATE2(fp_pair_map_impl, fp_pair_map_entry_s, node,
fp_pair_map_entry_hash, fp_pair_map_entries_eq,
0.6, tor_reallocarray_, tor_free_)
/** Constructor to create a new empty map from fp_pair_t to void *
*/
fp_pair_map_t *
fp_pair_map_new(void)
{
fp_pair_map_t *result;
result = tor_malloc(sizeof(fp_pair_map_t));
HT_INIT(fp_pair_map_impl, &result->head);
return result;
}
/** Set the current value for key to val; returns the previous
* value for key if one was set, or NULL if one was not.
*/
void *
fp_pair_map_set(fp_pair_map_t *map, const fp_pair_t *key, void *val)
{
fp_pair_map_entry_t *resolve;
fp_pair_map_entry_t search;
void *oldval;
tor_assert(map);
tor_assert(key);
tor_assert(val);
memcpy(&(search.key), key, sizeof(*key));
resolve = HT_FIND(fp_pair_map_impl, &(map->head), &search);
if (resolve) {
oldval = resolve->val;
resolve->val = val;
} else {
resolve = tor_malloc_zero(sizeof(fp_pair_map_entry_t));
memcpy(&(resolve->key), key, sizeof(*key));
resolve->val = val;
HT_INSERT(fp_pair_map_impl, &(map->head), resolve);
oldval = NULL;
}
return oldval;
}
/** Set the current value for the key (first, second) to val; returns
* the previous value for key if one was set, or NULL if one was not.
*/
void *
fp_pair_map_set_by_digests(fp_pair_map_t *map,
const char *first, const char *second,
void *val)
{
fp_pair_t k;
tor_assert(first);
tor_assert(second);
memcpy(k.first, first, DIGEST_LEN);
memcpy(k.second, second, DIGEST_LEN);
return fp_pair_map_set(map, &k, val);
}
/** Return the current value associated with key, or NULL if no value is set.
*/
void *
fp_pair_map_get(const fp_pair_map_t *map, const fp_pair_t *key)
{
fp_pair_map_entry_t *resolve;
fp_pair_map_entry_t search;
void *val = NULL;
tor_assert(map);
tor_assert(key);
memcpy(&(search.key), key, sizeof(*key));
resolve = HT_FIND(fp_pair_map_impl, &(map->head), &search);
if (resolve) val = resolve->val;
return val;
}
/** Return the current value associated the key (first, second), or
* NULL if no value is set.
*/
void *
fp_pair_map_get_by_digests(const fp_pair_map_t *map,
const char *first, const char *second)
{
fp_pair_t k;
tor_assert(first);
tor_assert(second);
memcpy(k.first, first, DIGEST_LEN);
memcpy(k.second, second, DIGEST_LEN);
return fp_pair_map_get(map, &k);
}
/** Remove the value currently associated with key from the map.
* Return the value if one was set, or NULL if there was no entry for
* key. The caller must free any storage associated with the
* returned value.
*/
void *
fp_pair_map_remove(fp_pair_map_t *map, const fp_pair_t *key)
{
fp_pair_map_entry_t *resolve;
fp_pair_map_entry_t search;
void *val = NULL;
tor_assert(map);
tor_assert(key);
memcpy(&(search.key), key, sizeof(*key));
resolve = HT_REMOVE(fp_pair_map_impl, &(map->head), &search);
if (resolve) {
val = resolve->val;
tor_free(resolve);
}
return val;
}
/** Remove all entries from map, and deallocate storage for those entries.
* If free_val is provided, it is invoked on every value in map.
*/
void
fp_pair_map_free(fp_pair_map_t *map, void (*free_val)(void*))
{
fp_pair_map_entry_t **ent, **next, *this;
if (map) {
for (ent = HT_START(fp_pair_map_impl, &(map->head));
ent != NULL; ent = next) {
this = *ent;
next = HT_NEXT_RMV(fp_pair_map_impl, &(map->head), ent);
if (free_val) free_val(this->val);
tor_free(this);
}
tor_assert(HT_EMPTY(&(map->head)));
HT_CLEAR(fp_pair_map_impl, &(map->head));
tor_free(map);
}
}
/** Return true iff map has no entries.
*/
int
fp_pair_map_isempty(const fp_pair_map_t *map)
{
tor_assert(map);
return HT_EMPTY(&(map->head));
}
/** Return the number of items in map.
*/
int
fp_pair_map_size(const fp_pair_map_t *map)
{
tor_assert(map);
return HT_SIZE(&(map->head));
}
/** return an iterator pointing to the start of map.
*/
fp_pair_map_iter_t *
fp_pair_map_iter_init(fp_pair_map_t *map)
{
tor_assert(map);
return HT_START(fp_pair_map_impl, &(map->head));
}
/** Advance iter a single step to the next entry of map, and return
* its new value.
*/
fp_pair_map_iter_t *
fp_pair_map_iter_next(fp_pair_map_t *map, fp_pair_map_iter_t *iter)
{
tor_assert(map);
tor_assert(iter);
return HT_NEXT(fp_pair_map_impl, &(map->head), iter);
}
/** Advance iter a single step to the next entry of map, removing the current
* entry, and return its new value.
*/
fp_pair_map_iter_t *
fp_pair_map_iter_next_rmv(fp_pair_map_t *map, fp_pair_map_iter_t *iter)
{
fp_pair_map_entry_t *rmv;
tor_assert(map);
tor_assert(iter);
tor_assert(*iter);
rmv = *iter;
iter = HT_NEXT_RMV(fp_pair_map_impl, &(map->head), iter);
tor_free(rmv);
return iter;
}
/** Set *key_out and *val_out to the current entry pointed to by iter.
*/
void
fp_pair_map_iter_get(fp_pair_map_iter_t *iter,
fp_pair_t *key_out, void **val_out)
{
tor_assert(iter);
tor_assert(*iter);
if (key_out) memcpy(key_out, &((*iter)->key), sizeof(fp_pair_t));
if (val_out) *val_out = (*iter)->val;
}
/** Return true iff iter has advanced past the last entry of its map.
*/
int
fp_pair_map_iter_done(fp_pair_map_iter_t *iter)
{
return (iter == NULL);
}
/** Assert if anything has gone wrong with the internal
* representation of map.
*/
void
fp_pair_map_assert_ok(const fp_pair_map_t *map)
{
tor_assert(!fp_pair_map_impl_HT_REP_IS_BAD_(&(map->head)));
}