public static IEnumerable ReadSizedBlocks(SqlFileInfo fileInfo, SqlInt64 offset, SqlByte sizing, [DefaultValue("NULL")] SqlInt32 maxCount)
{
if (fileInfo.IsNull || sizing.IsNull)
{
yield break;
}
var sizeEncoding = (SizeEncoding)sizing.Value;
if (sizeEncoding == SizeEncoding.NO)
{
yield break;
}
using (var fs = fileInfo.FileInfo.OpenRead())
{
if (!offset.IsNull)
{
fs.Position = offset.Value;
}
var position = fs.Position;
foreach (var block in fs.ReadCollection(s => s.TryReadBytes(sizeEncoding), maxCount.IsNull ? int.MaxValue : maxCount.Value))
{
yield return(Tuple.Create(position, block));
position = fs.Position;
}
}
}
public static IEnumerable ReadLinesByCpName(SqlFileInfo fileInfo, SqlInt64 offset, SqlString searchTerminator, SqlString delimiter, [DefaultValue("''")] SqlString newTerminator,
[DefaultValue("NULL")] SqlInt32 maxCount, SqlBoolean detectEncoding, [SqlFacet(MaxSize = 128)] SqlString cpName)
{
if (fileInfo.IsNull || searchTerminator.IsNull)
{
yield break;
}
var fileEncoding = cpName.IsNull ? SqlRuntime.FileEncoding : Encoding.GetEncoding(cpName.Value);
var terminatorsList = searchTerminator.IsNull || delimiter.Value.Length == 0 ? new[] { searchTerminator.Value } : searchTerminator.Value.Split(new[] { delimiter.Value }, StringSplitOptions.RemoveEmptyEntries);
using (var fs = fileInfo.FileInfo.OpenRead())
{
if (detectEncoding.IsTrue)
{
var preamble = EncodingPreamble.Detect(fs.ReadAt(0L, s => s.ReadBytesMost(1, 4)) ?? new byte[0]);
if (preamble != null)
{
fileEncoding = Encoding.GetEncoding(preamble.CodePage);
}
}
if (!offset.IsNull)
{
fs.Position = offset.Value;
}
var position = fs.Position;
foreach (var line in fs.ReadLines(fileEncoding, terminatorsList, newTerminator.IsNull ? null : newTerminator.Value, maxCount.IsNull ? int.MaxValue : maxCount.Value))
{
yield return(Tuple.Create(position, line));
position = fs.Position;
}
}
}
public static IEnumerable ReadTerminatedBlocks(SqlFileInfo fileInfo, SqlInt64 offset, SqlBytes searchTerminator, [DefaultValue("1")] SqlBoolean omitTerminator, [DefaultValue("NULL")] SqlInt32 maxCount)
{
if (fileInfo.IsNull || searchTerminator.IsNull)
{
yield break;
}
var terminator = searchTerminator.Value;
using (var fs = fileInfo.FileInfo.OpenRead())
{
if (!offset.IsNull)
{
fs.Position = offset.Value;
}
var position = fs.Position;
foreach (var block in fs.ReadCollection(s => s.TryReadBytes(terminator, omitTerminator.IsTrue), maxCount.IsNull ? int.MaxValue : maxCount.Value))
{
yield return(Tuple.Create(position, block));
position = fs.Position;
}
}
}
