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#include "MasterPTY.h"
#include "PTYMultiplexer.h"
#include "SlavePTY.h"
#include <Kernel/Process.h>
#include <LibC/errno_numbers.h>
#include <LibC/signal_numbers.h>
#include <LibC/sys/ioctl_numbers.h>
//#define MASTERPTY_DEBUG
MasterPTY::MasterPTY(unsigned index)
: CharacterDevice(10, index)
, m_slave(adopt(*new SlavePTY(*this, index)))
, m_index(index)
{
m_pts_name = String::format("/dev/pts/%u", m_index);
set_uid(current->process().uid());
set_gid(current->process().gid());
}
MasterPTY::~MasterPTY()
{
#ifdef MASTERPTY_DEBUG
dbgprintf("~MasterPTY(%u)\n", m_index);
#endif
PTYMultiplexer::the().notify_master_destroyed({}, m_index);
}
String MasterPTY::pts_name() const
{
return m_pts_name;
}
ssize_t MasterPTY::read(FileDescription&, byte* buffer, ssize_t size)
{
if (!m_slave && m_buffer.is_empty())
return 0;
return m_buffer.read(buffer, size);
}
ssize_t MasterPTY::write(FileDescription&, const byte* buffer, ssize_t size)
{
if (!m_slave)
return -EIO;
m_slave->on_master_write(buffer, size);
return size;
}
bool MasterPTY::can_read(FileDescription&) const
{
if (!m_slave)
return true;
return !m_buffer.is_empty();
}
bool MasterPTY::can_write(FileDescription&) const
{
return true;
}
void MasterPTY::notify_slave_closed(Badge<SlavePTY>)
{
#ifdef MASTERPTY_DEBUG
dbgprintf("MasterPTY(%u): slave closed, my retains: %u, slave retains: %u\n", m_index, retain_count(), m_slave->retain_count());
#endif
// +1 retain for my MasterPTY::m_slave
// +1 retain for FileDescription::m_device
if (m_slave->retain_count() == 2)
m_slave = nullptr;
}
ssize_t MasterPTY::on_slave_write(const byte* data, ssize_t size)
{
if (m_closed)
return -EIO;
m_buffer.write(data, size);
return size;
}
bool MasterPTY::can_write_from_slave() const
{
if (m_closed)
return true;
return m_buffer.bytes_in_write_buffer() < 4096;
}
void MasterPTY::close()
{
if (retain_count() == 2) {
InterruptDisabler disabler;
// After the closing FileDescription dies, slave is the only thing keeping me alive.
// From this point, let's consider ourselves closed.
m_closed = true;
m_slave->hang_up();
}
}
int MasterPTY::ioctl(FileDescription& description, unsigned request, unsigned arg)
{
if (request == TIOCSWINSZ)
return m_slave->ioctl(description, request, arg);
return -EINVAL;
}
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