public void EndOfStream()
{
var str = "Hello World!";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
bs.Read(12);
Assert.IsTrue(bs.EndOfStream);
Assert.AreEqual(-1, bs.Read());
}
}
public void PeekAndReadEqual()
{
var str = "Hello World!";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
Assert.Equal('H', bs.Peek());
Assert.Equal('H', bs.Read());
}
}
public void PeekAreChangedAfterRead()
{
var str = "abcdefghijkl";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
Assert.Equal('a', bs.Peek());
Assert.Equal('a', bs.Read());
Assert.Equal('b', bs.Peek());
Assert.Equal('b', bs.Read());
Assert.Equal('c', bs.Peek());
Assert.Equal('c', bs.Read());
Assert.Equal('d', bs.Peek());
Assert.Equal('d', bs.Read());
Assert.Equal('e', bs.Peek());
Assert.Equal('e', bs.Read());
}
}
public void ReadZeroBytes()
{
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes("Hello World!")))
using (var bs = new BencodeStream(ms))
{
var bytes = bs.Read(0);
Assert.AreEqual(0, bytes.Length);
Assert.AreEqual("", Encoding.UTF8.GetString(bytes));
}
}
public void ReadUnnaffectedByReadPrevious()
{
var str = "abcdefghijkl";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
Assert.AreEqual('a', bs.Read());
bs.ReadPrevious();
Assert.AreEqual('b', bs.Read());
}
}
public void ReadPreviousUnaffectedByPeek()
{
var str = "Hello World!";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
bs.Read(1);
Assert.AreEqual('H', bs.ReadPrevious());
Assert.AreEqual('e', bs.Peek());
Assert.AreEqual('H', bs.ReadPrevious());
}
}
public void ReadPreviousChar()
{
var str = "Hello World!";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
Assert.AreEqual(default(char), bs.ReadPreviousChar());
bs.Read(1);
Assert.AreEqual('H', bs.ReadPreviousChar());
}
}
public void ReadPrevious()
{
var str = "Hello World!";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
Assert.AreEqual(-1, bs.ReadPrevious());
Assert.AreEqual('H', bs.Read());
Assert.AreEqual('H', bs.ReadPrevious());
Assert.AreEqual('e', bs.Read());
Assert.AreEqual('e', bs.ReadPrevious());
bs.Position = 20;
Assert.AreEqual(-1, bs.ReadPrevious());
}
}
public void ReadMoreBytesThanInStream()
{
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes("Hello World!")))
using (var bs = new BencodeStream(ms))
{
var bytes = bs.Read(20);
Assert.AreEqual(12, bytes.Length);
Assert.AreEqual("Hello World!", Encoding.UTF8.GetString(bytes));
}
}
public void ReadBytesChangesStreamPosition()
{
var str = "Hello World!";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
Assert.AreEqual(0, bs.Position);
var bytes = bs.Read(str.Length);
Assert.AreEqual(12, bytes.Length);
Assert.AreEqual(str, Encoding.UTF8.GetString(bytes));
Assert.AreEqual(12, bs.Position);
}
}
public void Read()
{
var str = "Hello World!";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
Assert.AreEqual('H', bs.Read());
Assert.AreEqual('e', bs.Read());
Assert.AreEqual('l', bs.Read());
Assert.AreEqual('l', bs.Read());
Assert.AreEqual('o', bs.Read());
Assert.AreEqual(' ', bs.Read());
Assert.AreEqual('W', bs.Read());
Assert.AreEqual('o', bs.Read());
Assert.AreEqual('r', bs.Read());
Assert.AreEqual('l', bs.Read());
Assert.AreEqual('d', bs.Read());
Assert.AreEqual('!', bs.Read());
Assert.AreEqual(-1, bs.Read());
}
}
public void PeekAtEndOfStreamThenReadSingleByte()
{
var str = "abcdefghijkl";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
bs.Read(12);
Assert.AreEqual(-1, bs.Peek());
Assert.AreEqual(-1, bs.Read());
}
}
public void PeekAreChangedAfterReadSingleByte()
{
var str = "abcdefghijkl";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
byte[] bytes;
Assert.AreEqual('a', bs.Peek());
bytes = bs.Read(1);
Assert.AreEqual('a', (char)bytes[0]);
Assert.AreEqual('b', bs.Peek());
bytes = bs.Read(1);
Assert.AreEqual('b', (char)bytes[0]);
Assert.AreEqual('c', bs.Peek());
}
}
public static BString DecodeString(BencodeStream stream, Encoding encoding)
{
if (stream == null) throw new ArgumentNullException("stream");
if (encoding == null) throw new ArgumentNullException("encoding");
// Minimum valid bencode string is '0:' meaning an empty string
if (stream.Length < 2)
throw new BencodeDecodingException<BString>("Minimum valid stream length is 2 (an empty string: '0:')", stream.Position);
var lengthChars = new List<char>();
while (!stream.EndOfStream)
{
var c = stream.ReadChar();
// Break when we reach ':' if it is not the first character found
if (lengthChars.Count > 0 && c == ':')
break;
// Character then must be a digit
if (!c.IsDigit())
{
if (lengthChars.Count == 0)
throw new BencodeDecodingException<BString>(string.Format("Must begin with an integer but began with '{0}'", c), stream.Position);
// We have found some digits but this is neither a digit nor a ':' as expected
throw new BencodeDecodingException<BString>("Delimiter ':' was not found.", stream.Position);
}
// Because of memory limitations (~1-2 GB) we know for certain we cannot handle more than 10 digits (10GB)
if (lengthChars.Count >= BString.LengthMaxDigits)
{
throw new UnsupportedBencodeException(
string.Format("Length of string is more than {0} digits (>10GB) and is not supported (max is ~1-2GB).", BString.LengthMaxDigits),
stream.Position);
}
lengthChars.Add(c);
}
var stringLength = long.Parse(lengthChars.AsString());
// Int32.MaxValue is ~2GB and is the absolute maximum that can be handled in memory
if (stringLength > int.MaxValue)
{
throw new UnsupportedBencodeException(
string.Format("Length of string is {0:N0} but maximum supported length is {1:N0}.", stringLength, int.MaxValue),
stream.Position);
}
// TODO: Catch possible OutOfMemoryException when stringLength is close Int32.MaxValue ?
var bytes = stream.Read((int)stringLength);
// If the two don't match we've reached the end of the stream before reading the expected number of chars
if (bytes.Length != stringLength)
{
throw new BencodeDecodingException<BString>(
string.Format("Expected string to be {0:N0} bytes long but could only read {1:N0} bytes.", stringLength, bytes.Length),
stream.Position);
}
return new BString(bytes, encoding);
}
public void ReadChangeStreamPosition()
{
var str = "Hello World!";
using (var ms = new MemoryStream(Encoding.UTF8.GetBytes(str)))
using (var bs = new BencodeStream(ms))
{
Assert.Equal('H', bs.Read());
Assert.Equal('e', bs.Read());
bs.Position -= 1;
Assert.Equal('e', bs.Read());
}
}
