public bool TryPutOctal(long value, TarHeader.HeaderField field)
{
if (value >= 0)
{
var str = Convert.ToString(value, 8);
if (str.Length < field.Length)
{
int leadingZeroes = field.Length - str.Length - 1;
for (int i = 0; i < leadingZeroes; i++)
{
this[field.Offset + i] = (byte)'0';
}
for (int i = 0; i < str.Length; i++)
{
this[field.Offset + leadingZeroes + i] = (byte)str[i];
}
this[field.Offset + field.Length - 1] = 0;
return(true);
}
}
if (field.PaxAttribute != null && PaxAttributes != null)
{
PaxAttributes[field.PaxAttribute] = value.ToString();
}
PutNul(field);
return(false);
}
public bool TryPutString(string str, TarHeader.HeaderField field)
{
if (str == null)
{
PutNul(field);
return(true);
}
if (TarCommon.IsASCII(str))
{
if (str.Length <= field.Length)
{
for (int i = 0; i < str.Length; i++)
{
this[field.Offset + i] = (byte)str[i];
}
PutNul(field.Offset + str.Length, field.Length - str.Length);
return(true);
}
}
if (field.PaxAttribute != null && PaxAttributes != null)
{
PaxAttributes[field.PaxAttribute] = str;
}
PutNul(field);
return(false);
}
public void PutBytes(ArraySegment <byte> bytes, TarHeader.HeaderField field)
{
int i;
for (i = 0; i < bytes.Count && i < field.Length; i++)
{
this[field.Offset + i] = bytes.Array[bytes.Offset + i];
}
PutNul(field.Offset + i, field.Length - i);
}
public int GetOctal(TarHeader.HeaderField field)
{
long value = GetOctalLong(field);
if ((int)value != value)
{
throw new TarParseException("value too large");
}
return((int)value);
}
public DateTime GetTime(TarHeader.HeaderField field)
{
string paxValue = GetPaxValue(field.PaxAttribute);
if (paxValue != null)
{
return(TarTime.FromPaxTime(paxValue));
}
long unixTime = GetOctalLong(field.WithoutPax);
if (unixTime < TarTime.MinUnixTime)
{
unixTime = TarTime.MinUnixTime;
}
else if (unixTime > TarTime.MaxUnixTime)
{
unixTime = TarTime.MaxUnixTime;
}
return(TarTime.FromUnixTime(unixTime, 0));
}
public long GetOctalLong(TarHeader.HeaderField field)
{
string paxValue = GetPaxValue(field.PaxAttribute);
if (paxValue != null)
{
return(Convert.ToInt64(paxValue));
}
var firstByte = this[field.Offset];
if ((firstByte & 0x80) != 0)
{
// Tar extension: value is encoded as MSB (ignoring the high bit of the first byte).
if ((firstByte & 0x40) == 0)
{
// The result is positive, so clear the sign bit.
firstByte &= 0x7f;
}
long result = (sbyte)firstByte;
for (int i = 1; i < field.Length; i++)
{
result <<= 8;
result |= this[field.Offset + i];
}
return(result);
}
else
{
var str = GetString(field.WithoutPax).Trim(nulAndSpace);
if (str.Length == 0)
{
return(0);
}
return(Convert.ToInt64(str, 8));
}
}
public bool TryPutTime(DateTime time, TarHeader.HeaderField field)
{
uint nanoseconds = 0;
long unixTime = 0;
if (time.Ticks != 0)
{
unixTime = TarTime.ToUnixTime(time, out nanoseconds);
}
if (TryPutOctal(unixTime, field.WithoutPax) && nanoseconds == 0)
{
return(true);
}
if (field.PaxAttribute != null && PaxAttributes != null)
{
PaxAttributes[field.PaxAttribute] = TarTime.ToPaxTime(time);
}
return(false);
}
public string GetString(TarHeader.HeaderField field)
{
string paxValue = GetPaxValue(field.PaxAttribute);
if (paxValue != null)
{
return(paxValue);
}
int i;
for (i = 0; i < field.Length; i++)
{
var b = this[field.Offset + i];
if (b == 0)
{
break;
}
}
// Assume UTF-8 encoding. This may not be correct always, but only PAX rigorously
// defines the encoding of strings.
return(TarCommon.UTF8.GetString(_buffer, _offset + field.Offset, i));
}
public ArraySegment <byte> Field(TarHeader.HeaderField field)
{
return(new ArraySegment <byte>(_buffer, _offset + field.Offset, field.Length));
}
public void PutNul(TarHeader.HeaderField field)
{
PutNul(field.Offset, field.Length);
}
