// Token: 0x0600159F RID: 5535 RVA: 0x0008016C File Offset: 0x0007E36C
internal static int CopyStream(Stream source, Stream target, int offset, int count, bool needCrc, out uint crc)
{
byte[] array = null;
int num = 0;
crc = 0U;
if (count == 0)
{
return(0);
}
if (count < 0)
{
count = int.MaxValue;
}
try
{
array = StreamHelper.bytesBufferPool.Acquire();
if (array == null)
{
throw new InvalidOperationException("buffer should never be null.");
}
int num2;
if (source.CanSeek)
{
source.Seek((long)offset, SeekOrigin.Begin);
}
else if (offset > 0)
{
do
{
num2 = source.Read(array, 0, (offset < array.Length) ? offset : array.Length);
offset -= num2;
}while (num2 > 0 && offset > 0);
}
do
{
num2 = source.Read(array, 0, (count < array.Length) ? count : array.Length);
if (num2 != 0)
{
target.Write(array, 0, num2);
if (needCrc)
{
crc = StreamHelper.UpdateCrc32(crc, array, 0, num2);
}
AirSyncDiagnostics.TraceBinaryData(ExTraceGlobals.RawBodyBytesTracer, null, array, num2);
count -= num2;
num += num2;
}
}while (num2 > 0 && count > 0);
}
finally
{
if (array != null)
{
StreamHelper.bytesBufferPool.Release(array);
}
}
return(num);
}