/// <summary>
/// Sets the length of the stream.
/// </summary>
/// <param name="value">The new length in bytes.</param>
/// <remarks>
/// The stream will be truncated if the new length is less than
/// the current length. The stream will be extended if the new
/// length is greater than the current length. In this case,
/// the contents of the extended portion will be undefined.
/// </remarks>
public override void SetLength(long value)
{
int cb;
if (value < 0 || value > int.MaxValue)
{
throw new IOException(TooLongError);
}
cb = (int)value;
if (cb < length)
{
length = cb;
blocks.TruncateTo(length);
if (pos > length)
{
pos = length;
}
}
else if (cb > length)
{
length = cb;
blocks.ExtendTo(length);
}
}
public void TruncateTo()
{
BlockArray blocks;
blocks = new BlockArray();
blocks.TruncateTo(0);
Assert.Equal(0, blocks.Size);
Assert.Empty(blocks.GetBlocks());
blocks.ExtendTo(1);
blocks.TruncateTo(1);
Assert.Equal(blocks.BlockSize, blocks.Size);
Assert.Single(blocks.GetBlocks());
blocks.TruncateTo(1000000);
blocks.TruncateTo(1);
Assert.Equal(blocks.BlockSize, blocks.Size);
Assert.Single(blocks.GetBlocks());
blocks.TruncateTo(0);
Assert.Equal(0, blocks.Size);
Assert.Empty(blocks.GetBlocks());
blocks.ExtendTo(blocks.BlockSize * 4);
blocks.GetBlocks()[0].Buffer[0] = 0;
blocks.GetBlocks()[1].Buffer[0] = 1;
blocks.GetBlocks()[2].Buffer[0] = 2;
blocks.GetBlocks()[3].Buffer[0] = 3;
blocks.TruncateTo(blocks.BlockSize * 3);
Assert.Equal(blocks.BlockSize * 3, blocks.Size);
Assert.Equal(3, blocks.GetBlocks().Length);
Assert.Equal(0, blocks.GetBlocks()[0].Buffer[0]);
Assert.Equal(1, blocks.GetBlocks()[1].Buffer[0]);
Assert.Equal(2, blocks.GetBlocks()[2].Buffer[0]);
blocks.TruncateTo(blocks.BlockSize * 2 + 1);
Assert.Equal(blocks.BlockSize * 3, blocks.Size);
Assert.Equal(3, blocks.GetBlocks().Length);
Assert.Equal(0, blocks.GetBlocks()[0].Buffer[0]);
Assert.Equal(1, blocks.GetBlocks()[1].Buffer[0]);
Assert.Equal(2, blocks.GetBlocks()[2].Buffer[0]);
blocks.TruncateTo(blocks.BlockSize);
Assert.Equal(blocks.BlockSize, blocks.Size);
Assert.Single(blocks.GetBlocks());
Assert.Equal(0, blocks.GetBlocks()[0].Buffer[0]);
}