internal static int GetRootLength(ReadOnlySpan <char> path)
{
int length = path.Length;
int index = 0;
bool flag1 = PathInternal.IsDevice(path);
bool flag2 = flag1 && PathInternal.IsDeviceUNC(path);
if (!flag1 | flag2 && length > 0 && PathInternal.IsDirectorySeparator(path[0]))
{
if (flag2 || length > 1 && PathInternal.IsDirectorySeparator(path[1]))
{
index = flag2 ? 8 : 2;
int num = 2;
while (index < length && (!PathInternal.IsDirectorySeparator(path[index]) || --num > 0))
{
++index;
}
}
else
{
index = 1;
}
}
else if (flag1)
{
index = 4;
while (index < length && !PathInternal.IsDirectorySeparator(path[index]))
{
++index;
}
if (index < length && index > 4 && PathInternal.IsDirectorySeparator(path[index]))
{
++index;
}
}
else if (length >= 2 && path[1] == ':' && PathInternal.IsValidDriveChar(path[0]))
{
index = 2;
if (length > 2 && PathInternal.IsDirectorySeparator(path[2]))
{
++index;
}
}
return(index);
}
