ladybird/Kernel/TTY/PTYMultiplexer.cpp

53 lines
1.2 KiB
C++

#include "PTYMultiplexer.h"
#include "MasterPTY.h"
#include <Kernel/FileSystem/FileDescriptor.h>
#include <Kernel/Process.h>
#include <LibC/errno_numbers.h>
//#define PTMX_DEBUG
static const unsigned s_max_pty_pairs = 8;
static PTYMultiplexer* s_the;
PTYMultiplexer& PTYMultiplexer::the()
{
ASSERT(s_the);
return *s_the;
}
PTYMultiplexer::PTYMultiplexer()
: CharacterDevice(5, 2)
{
s_the = this;
m_freelist.ensure_capacity(s_max_pty_pairs);
for (int i = s_max_pty_pairs; i > 0; --i)
m_freelist.unchecked_append(i - 1);
}
PTYMultiplexer::~PTYMultiplexer()
{
}
KResultOr<Retained<FileDescriptor>> PTYMultiplexer::open(int options)
{
UNUSED_PARAM(options);
LOCKER(m_lock);
if (m_freelist.is_empty())
return KResult(-EBUSY);
auto master_index = m_freelist.take_last();
auto master = adopt(*new MasterPTY(master_index));
#ifdef PTMX_DEBUG
dbgprintf("PTYMultiplexer::open: Vending master %u\n", master->index());
#endif
return FileDescriptor::create(master.ptr());
}
void PTYMultiplexer::notify_master_destroyed(Badge<MasterPTY>, unsigned index)
{
LOCKER(m_lock);
m_freelist.append(index);
#ifdef PTMX_DEBUG
dbgprintf("PTYMultiplexer: %u added to freelist\n", index);
#endif
}