U_CAPI int32_t U_EXPORT2
uhash_igeti(const UHashtable *hash,
int32_t key) {
UHashTok keyholder;
keyholder.integer = key;
return _uhash_find(hash, keyholder, hash->keyHasher(keyholder))->value.integer;
}
U_CAPI int32_t U_EXPORT2
uhash_geti(const UHashtable *hash,
const void* key) {
UHashTok keyholder;
keyholder.pointer = (void*) key;
return _uhash_find(hash, keyholder, hash->keyHasher(keyholder))->value.integer;
}
U_CAPI const UHashElement* U_EXPORT2
uhash_find(const UHashtable *hash, const void* key) {
UHashTok keyholder;
const UHashElement *e;
keyholder.pointer = (void*) key;
e = _uhash_find(hash, keyholder, hash->keyHasher(keyholder));
return IS_EMPTY_OR_DELETED(e->hashcode) ? NULL : e;
}
U_CAPI UBool U_EXPORT2
uhash_equals(const UHashtable* hash1, const UHashtable* hash2){
int32_t count1, count2, pos, i;
if(hash1==hash2){
return TRUE;
}
/*
* Make sure that we are comparing 2 valid hashes of the same type
* with valid comparison functions.
* Without valid comparison functions, a binary comparison
* of the hash values will yield random results on machines
* with 64-bit pointers and 32-bit integer hashes.
* A valueComparator is normally optional.
*/
if (hash1==NULL || hash2==NULL ||
hash1->keyComparator != hash2->keyComparator ||
hash1->valueComparator != hash2->valueComparator ||
hash1->valueComparator == NULL)
{
/*
Normally we would return an error here about incompatible hash tables,
but we return FALSE instead.
*/
return FALSE;
}
count1 = uhash_count(hash1);
count2 = uhash_count(hash2);
if(count1!=count2){
return FALSE;
}
pos=-1;
for(i=0; i<count1; i++){
const UHashElement* elem1 = uhash_nextElement(hash1, &pos);
const UHashTok key1 = elem1->key;
const UHashTok val1 = elem1->value;
/* here the keys are not compared, instead the key form hash1 is used to fetch
* value from hash2. If the hashes are equal then then both hashes should
* contain equal values for the same key!
*/
const UHashElement* elem2 = _uhash_find(hash2, key1, hash2->keyHasher(key1));
const UHashTok val2 = elem2->value;
if(hash1->valueComparator(val1, val2)==FALSE){
return FALSE;
}
}
return TRUE;
}
/**
* Attempt to grow or shrink the data arrays in order to make the
* count fit between the high and low water marks. hash_put() and
* hash_remove() call this method when the count exceeds the high or
* low water marks. This method may do nothing, if memory allocation
* fails, or if the count is already in range, or if the length is
* already at the low or high limit. In any case, upon return the
* arrays will be valid.
*/
static void
_uhash_rehash(UHashtable *hash) {
UHashElement *old = hash->elements;
int32_t oldLength = hash->length;
int32_t newPrimeIndex = hash->primeIndex;
int32_t i;
UErrorCode status = U_ZERO_ERROR;
if (hash->count > hash->highWaterMark) {
if (++newPrimeIndex >= PRIMES_LENGTH) {
return;
}
} else if (hash->count < hash->lowWaterMark) {
if (--newPrimeIndex < 0) {
return;
}
} else {
return;
}
_uhash_allocate(hash, newPrimeIndex, &status);
if (U_FAILURE(status)) {
hash->elements = old;
hash->length = oldLength;
return;
}
for (i = oldLength - 1; i >= 0; --i) {
if (!IS_EMPTY_OR_DELETED(old[i].hashcode)) {
UHashElement *e = _uhash_find(hash, old[i].key, old[i].hashcode);
U_ASSERT(e != NULL);
U_ASSERT(e->hashcode == HASH_EMPTY);
e->key = old[i].key;
e->value = old[i].value;
e->hashcode = old[i].hashcode;
++hash->count;
}
}
uprv_free(old);
}
static UHashTok
_uhash_remove(UHashtable *hash,
UHashTok key) {
/* First find the position of the key in the table. If the object
* has not been removed already, remove it. If the user wanted
* keys deleted, then delete it also. We have to put a special
* hashcode in that position that means that something has been
* deleted, since when we do a find, we have to continue PAST any
* deleted values.
*/
UHashTok result;
UHashElement* e = _uhash_find(hash, key, hash->keyHasher(key));
U_ASSERT(e != NULL);
result.pointer = NULL; result.integer = 0;
if (!IS_EMPTY_OR_DELETED(e->hashcode)) {
result = _uhash_internalRemoveElement(hash, e);
if (hash->count < hash->lowWaterMark) {
_uhash_rehash(hash);
}
}
return result;
}
static UHashTok
_uhash_put(UHashtable *hash,
UHashTok key,
UHashTok value,
int8_t hint,
UErrorCode *status) {
/* Put finds the position in the table for the new value. If the
* key is already in the table, it is deleted, if there is a
* non-NULL keyDeleter. Then the key, the hash and the value are
* all put at the position in their respective arrays.
*/
int32_t hashcode;
UHashElement* e;
UHashTok emptytok;
if (U_FAILURE(*status)) {
goto err;
}
U_ASSERT(hash != NULL);
/* Cannot always check pointer here or iSeries sees NULL every time. */
if ((hint & HINT_VALUE_POINTER) && value.pointer == NULL) {
/* Disallow storage of NULL values, since NULL is returned by
* get() to indicate an absent key. Storing NULL == removing.
*/
return _uhash_remove(hash, key);
}
if (hash->count > hash->highWaterMark) {
_uhash_rehash(hash);
}
hashcode = (*hash->keyHasher)(key);
e = _uhash_find(hash, key, hashcode);
U_ASSERT(e != NULL);
if (IS_EMPTY_OR_DELETED(e->hashcode)) {
/* Important: We must never actually fill the table up. If we
* do so, then _uhash_find() will return NULL, and we'll have
* to check for NULL after every call to _uhash_find(). To
* avoid this we make sure there is always at least one empty
* or deleted slot in the table. This only is a problem if we
* are out of memory and rehash isn't working.
*/
++hash->count;
if (hash->count == hash->length) {
/* Don't allow count to reach length */
--hash->count;
*status = U_MEMORY_ALLOCATION_ERROR;
goto err;
}
}
/* We must in all cases handle storage properly. If there was an
* old key, then it must be deleted (if the deleter != NULL).
* Make hashcodes stored in table positive.
*/
return _uhash_setElement(hash, e, hashcode & 0x7FFFFFFF, key, value, hint);
err:
/* If the deleters are non-NULL, this method adopts its key and/or
* value arguments, and we must be sure to delete the key and/or
* value in all cases, even upon failure.
*/
HASH_DELETE_KEY_VALUE(hash, key.pointer, value.pointer);
emptytok.pointer = NULL; emptytok.integer = 0;
return emptytok;
}
