Kernel: Move TTY-related files into Kernel/TTY/.

Kernel/TTY/MasterPTY.cpp

@@ -0,0 +1,103 @@
+#include "MasterPTY.h"
+#include "SlavePTY.h"
+#include "PTYMultiplexer.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)
+{
+    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(Badge<MasterPTY>(), m_index);
+}
+
+String MasterPTY::pts_name() const
+{
+    return String::format("/dev/pts/%u", m_index);
+}
+
+ssize_t MasterPTY::read(Process&, byte* buffer, ssize_t size)
+{
+    if (!m_slave && m_buffer.is_empty())
+        return 0;
+    return m_buffer.read(buffer, size);
+}
+
+ssize_t MasterPTY::write(Process&, const byte* buffer, ssize_t size)
+{
+    if (!m_slave)
+        return -EIO;
+    m_slave->on_master_write(buffer, size);
+    return size;
+}
+
+bool MasterPTY::can_read(Process&) const
+{
+    if (!m_slave)
+        return true;
+    return !m_buffer.is_empty();
+}
+
+bool MasterPTY::can_write(Process&) 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 FileDescriptor::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 FileDescriptor 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(Process& process, unsigned request, unsigned arg)
+{
+    if (request == TIOCSWINSZ)
+        return m_slave->ioctl(process, request, arg);
+    return -EINVAL;
+}