/*
* Returns the identifier in a given encoding to which a unit associated with
* a unit-system maps.
*
* Arguments:
* systemMap Pointer to the system-to-unit-to-id map.
* unit Pointer to the unit whose identifier should be returned.
* encoding The desired encoding of the identifier.
* Returns:
* NULL Failure. "ut_get_status()" will be
* UT_BAD_ARG "unit" was NULL.
* else Pointer to the identifier in the given encoding
* associated with "unit".
*/
static const char*
getId(
SystemMap* const systemMap,
const ut_unit* const unit,
const ut_encoding encoding)
{
const char* id = NULL; /* failure */
if (unit == NULL) {
ut_set_status(UT_BAD_ARG);
ut_handle_error_message("NULL unit argument");
}
else {
UnitToIdMap** const unitToId =
(UnitToIdMap**)smFind(systemMap, ut_get_system(unit));
if (unitToId != NULL) {
UnitAndId* mapEntry =
encoding == UT_LATIN1
? utimFindLatin1ByUnit(*unitToId, unit)
: encoding == UT_UTF8
? utimFindUtf8ByUnit(*unitToId, unit)
: utimFindAsciiByUnit(*unitToId, unit);
if (mapEntry != NULL)
id = mapEntry->id;
}
}
return id;
}
/*
* Returns the unit to which an identifier maps in a particular unit-system.
*
* Arguments:
* systemMap NULL or pointer to the system-map. If NULL, then
* NULL will be returned.
* system Pointer to the unit-system.
* id Pointer to the identifier.
* Returns:
* NULL Failure. "ut_get_status()" will be:
* UT_BAD_ARG "system" is NULL or "id" is NULL.
* else Pointer to the unit in "system" with the identifier "id".
* Should be passed to ut_free() when no longer needed.
*/
static ut_unit*
getUnitById(
const SystemMap* const systemMap,
const ut_system* const system,
const char* const id)
{
ut_unit* unit = NULL; /* failure */
if (system == NULL) {
ut_set_status(UT_BAD_ARG);
ut_handle_error_message("getUnitById(): NULL unit-system argument");
}
else if (id == NULL) {
ut_set_status(UT_BAD_ARG);
ut_handle_error_message("getUnitById(): NULL identifier argument");
}
else if (systemMap != NULL) {
IdToUnitMap** const idToUnit =
(IdToUnitMap**)smFind(systemMap, system);
if (idToUnit != NULL) {
const UnitAndId* uai = itumFind(*idToUnit, id);
if (uai != NULL)
unit = ut_clone(uai->unit);
}
} /* valid arguments */
return unit;
}
/*
* Removes an entry from the unit-to-identifier map associated with a
* unit-system.
*
* Arguments:
* sytemMap Pointer to the system-to-unit-to-identifier map.
* unit The unit. May be freed upon return.
* encoding The ostensible encoding of "id".
* Returns:
* UT_BAD_ARG "systemMap" is NULL.
* UT_BAD_ARG "unit" is NULL.
* UT_SUCCESS Success.
*/
static ut_status
unmapUnitToId(
SystemMap* const systemMap,
const ut_unit* const unit,
ut_encoding encoding)
{
ut_status status;
if (systemMap == NULL || unit == NULL) {
status = UT_BAD_ARG;
}
else {
UnitToIdMap** const unitToIdMap =
(UnitToIdMap**)smFind(systemMap, ut_get_system(unit));
status =
(unitToIdMap == NULL || *unitToIdMap == NULL)
? UT_SUCCESS
: utimRemove(*unitToIdMap, unit, encoding);
}
return status;
}
/*
* Removes the mapping from an identifier to a unit.
*
* Arguments:
* systemMap Address of the pointer to the system-map.
* id Pointer to the identifier. May be freed upon return.
* system Pointer to the unit-system associated with the mapping.
* Returns:
* UT_BAD_ARG "id" is NULL, "system" is NULL, or "compare" is NULL.
* UT_SUCCESS Success.
*/
static ut_status
unmapId(
SystemMap* const systemMap,
const char* const id,
ut_system* system)
{
ut_status status;
if (systemMap == NULL || id == NULL || system == NULL) {
status = UT_BAD_ARG;
}
else {
IdToUnitMap** const idToUnit =
(IdToUnitMap**)smFind(systemMap, system);
status =
(idToUnit == NULL || *idToUnit == NULL)
? UT_SUCCESS
: itumRemove(*idToUnit, id);
} /* valid arguments */
return status;
}
/*
* Frees resources associated with a unit-system.
*
* Arguments:
* system Pointer to the unit-system to have its associated
* resources freed.
*/
void
utimFreeSystem(
ut_system* system)
{
if (system != NULL) {
SystemMap* systemMaps[2];
int i;
systemMaps[0] = systemToUnitToName;
systemMaps[1] = systemToUnitToSymbol;
for (i = 0; i < 2; i++) {
if (systemMaps[i] != NULL) {
UnitToIdMap** const unitToId =
(UnitToIdMap**)smFind(systemMaps[i], system);
if (unitToId != NULL)
utimFree(*unitToId);
smRemove(systemMaps[i], system);
}
}
}
}
/*
* Frees resources associated with a unit-system.
*
* Arguments:
* system Pointer to the unit-system to have its associated
* resources freed.
*/
void
itumFreeSystem(
ut_system* system)
{
if (system != NULL) {
SystemMap* systemMaps[2];
int i;
systemMaps[0] = systemToNameToUnit;
systemMaps[1] = systemToSymbolToUnit;
for (i = 0; i < 2; i++) {
if (systemMaps[i] != NULL) {
IdToUnitMap** const idToUnit =
(IdToUnitMap**)smFind(systemMaps[i], system);
if (idToUnit != NULL)
itumFree(*idToUnit);
smRemove(systemMaps[i], system);
}
}
} /* valid arguments */
}
