internal static IEnumerable <TzdbStreamField> ReadFields(Stream input)
{
while (true)
{
int fieldId = input.ReadByte();
if (fieldId == -1)
{
yield break;
}
TzdbStreamFieldId id = (TzdbStreamFieldId)(byte)fieldId;
// Read 7-bit-encoded length
int length = new DateTimeZoneReader(input, null).ReadCount();
byte[] data = new byte[length];
int offset = 0;
while (offset < data.Length)
{
int bytesRead = input.Read(data, offset, data.Length - offset);
if (bytesRead == 0)
{
throw new InvalidNodaDataException("Stream ended after reading " + offset + " bytes out of " + data.Length);
}
offset += bytesRead;
}
yield return(new TzdbStreamField(id, data));
}
}
internal IDictionary <string, string> ExtractSingleValue(IList <string> stringPool)
{
using (var stream = CreateStream())
{
var reader = new DateTimeZoneReader(stream, stringPool);
return(reader.ReadDictionary());
}
}
internal void HandleStringPoolField(TzdbStreamField field)
{
CheckSingleField(field, stringPool);
using (var stream = field.CreateStream())
{
var reader = new DateTimeZoneReader(stream, null);
int count = reader.ReadCount();
stringPool = new string[count];
for (int i = 0; i < count; i++)
{
stringPool[i] = reader.ReadString();
}
}
}
internal void HandleZone1970LocationsField(TzdbStreamField field)
{
CheckSingleField(field, zone1970Locations);
CheckStringPoolPresence(field);
using (var stream = field.CreateStream())
{
var reader = new DateTimeZoneReader(stream, stringPool);
var count = reader.ReadCount();
var array = new TzdbZone1970Location[count];
for (int i = 0; i < count; i++)
{
array[i] = TzdbZone1970Location.Read(reader);
}
zone1970Locations = array;
}
}
internal void HandleZoneField(TzdbStreamField field)
{
CheckStringPoolPresence(field);
// Just read the ID from the zone - we don't parse the data yet.
// (We could, but we might as well be lazy.)
using (var stream = field.CreateStream())
{
var reader = new DateTimeZoneReader(stream, stringPool);
string id = reader.ReadString();
if (zoneFields.ContainsKey(id))
{
throw new InvalidNodaDataException("Multiple definitions for zone " + id);
}
zoneFields[id] = field;
}
}
/// <summary>
/// Creates the <see cref="DateTimeZone"/> for the given canonical ID, which will definitely
/// be one of the values of the TzdbAliases dictionary.
/// </summary>
/// <param name="id">ID for the returned zone, which may be an alias.</param>
/// <param name="canonicalId">Canonical ID for zone data</param>
public DateTimeZone CreateZone(string id, string canonicalId)
{
Preconditions.CheckNotNull(id, nameof(id));
Preconditions.CheckNotNull(canonicalId, nameof(canonicalId));
using (var stream = zoneFields[canonicalId].CreateStream())
{
var reader = new DateTimeZoneReader(stream, stringPool);
// Skip over the ID before the zone data itself
reader.ReadString();
var type = (DateTimeZoneWriter.DateTimeZoneType)reader.ReadByte();
return(type switch
{
DateTimeZoneWriter.DateTimeZoneType.Fixed => FixedDateTimeZone.Read(reader, id),
DateTimeZoneWriter.DateTimeZoneType.Precalculated =>
CachedDateTimeZone.ForZone(PrecalculatedDateTimeZone.Read(reader, id)),
_ => throw new InvalidNodaDataException("Unknown time zone type " + type)
});
/// <inheritdoc />
public DateTimeZone CreateZone(string id, string canonicalId)
{
using (var stream = zoneFields[canonicalId].CreateStream())
{
var reader = new DateTimeZoneReader(stream, stringPool);
// Skip over the ID before the zone data itself
reader.ReadString();
var type = (DateTimeZoneWriter.DateTimeZoneType)reader.ReadByte();
switch (type)
{
case DateTimeZoneWriter.DateTimeZoneType.Fixed:
return(FixedDateTimeZone.Read(reader, id));
case DateTimeZoneWriter.DateTimeZoneType.Precalculated:
return(CachedDateTimeZone.ForZone(PrecalculatedDateTimeZone.Read(reader, id)));
default:
throw new InvalidNodaDataException("Unknown time zone type " + type);
}
}
}
