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#pragma once
#include <LibCore/CEvent.h>
#include <LibCore/CEventLoop.h>
#include <LibCore/CIODevice.h>
#include <LibCore/CLocalSocket.h>
#include <LibCore/CNotifier.h>
#include <LibCore/CObject.h>
#include <errno.h>
#include <stdio.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <unistd.h>
//#define CIPC_DEBUG
namespace IPC {
namespace Server {
class Event : public CEvent {
public:
enum Type {
Invalid = 2000,
Disconnected,
};
Event() {}
explicit Event(Type type)
: CEvent(type)
{
}
};
class DisconnectedEvent : public Event {
public:
explicit DisconnectedEvent(int client_id)
: Event(Disconnected)
, m_client_id(client_id)
{
}
int client_id() const { return m_client_id; }
private:
int m_client_id { 0 };
};
template<typename T, class... Args>
T* new_connection_for_client(Args&&... args)
{
auto conn = new T(AK::forward<Args>(args)...) /* arghs */;
conn->send_greeting();
return conn;
};
template<typename ServerMessage, typename ClientMessage>
class Connection : public CObject {
C_OBJECT(Connection)
public:
Connection(CLocalSocket& socket, int client_id)
: m_socket(socket)
, m_client_id(client_id)
{
add_child(socket);
m_socket.on_ready_to_read = [this] { drain_client(); };
#if defined(CIPC_DEBUG)
dbg() << "S: Created new Connection " << fd << client_id << " and said hello";
#endif
}
~Connection()
{
#if defined(CIPC_DEBUG)
dbg() << "S: Destroyed Connection " << m_socket.fd() << client_id();
#endif
}
void post_message(const ServerMessage& message, const ByteBuffer& extra_data = {})
{
#if defined(CIPC_DEBUG)
dbg() << "S: -> C " << int(message.type) << " extra " << extra_data.size();
#endif
if (!extra_data.is_empty())
const_cast<ServerMessage&>(message).extra_size = extra_data.size();
struct iovec iov[2];
int iov_count = 1;
iov[0].iov_base = const_cast<ServerMessage*>(&message);
iov[0].iov_len = sizeof(message);
if (!extra_data.is_empty()) {
iov[1].iov_base = const_cast<u8*>(extra_data.data());
iov[1].iov_len = extra_data.size();
++iov_count;
}
int nwritten = writev(m_socket.fd(), iov, iov_count);
if (nwritten < 0) {
switch (errno) {
case EPIPE:
dbgprintf("Connection::post_message: Disconnected from peer.\n");
delete_later();
return;
break;
case EAGAIN:
dbgprintf("Connection::post_message: Client buffer overflowed.\n");
did_misbehave();
return;
break;
default:
perror("Connection::post_message writev");
ASSERT_NOT_REACHED();
}
}
ASSERT(nwritten == (int)(sizeof(message) + extra_data.size()));
}
void drain_client()
{
unsigned messages_received = 0;
for (;;) {
ClientMessage message;
// FIXME: Don't go one message at a time, that's so much context switching, oof.
ssize_t nread = recv(m_socket.fd(), &message, sizeof(ClientMessage), MSG_DONTWAIT);
if (nread == 0 || (nread == -1 && errno == EAGAIN)) {
if (!messages_received) {
// TODO: is delete_later() sufficient?
CEventLoop::current().post_event(*this, make<DisconnectedEvent>(client_id()));
}
break;
}
if (nread < 0) {
perror("recv");
ASSERT_NOT_REACHED();
}
ByteBuffer extra_data;
if (message.extra_size) {
if (message.extra_size >= 32768) {
dbgprintf("message.extra_size is way too large\n");
return did_misbehave();
}
extra_data = ByteBuffer::create_uninitialized(message.extra_size);
// FIXME: We should allow this to time out. Maybe use a socket timeout?
int extra_nread = read(m_socket.fd(), extra_data.data(), extra_data.size());
if (extra_nread != (int)message.extra_size) {
dbgprintf("extra_nread(%d) != extra_size(%d)\n", extra_nread, extra_data.size());
if (extra_nread < 0)
perror("read");
return did_misbehave();
}
}
#if defined(CIPC_DEBUG)
dbg() << "S: <- C " << int(message.type) << " extra " << extra_data.size();
#endif
if (!handle_message(message, move(extra_data)))
return;
++messages_received;
}
}
void did_misbehave()
{
dbgprintf("Connection{%p} (id=%d, pid=%d) misbehaved, disconnecting.\n", this, client_id(), m_client_pid);
m_socket.close();
delete_later();
}
int client_id() const { return m_client_id; }
pid_t client_pid() const { return m_client_pid; }
void set_client_pid(pid_t pid) { m_client_pid = pid; }
// ### having this public is sad
virtual void send_greeting() = 0;
protected:
void event(CEvent& event)
{
if (event.type() == Event::Disconnected) {
int client_id = static_cast<const DisconnectedEvent&>(event).client_id();
dbgprintf("Connection: Client disconnected: %d\n", client_id);
delete this;
return;
}
CObject::event(event);
}
virtual bool handle_message(const ClientMessage&, const ByteBuffer&& = {}) = 0;
private:
CLocalSocket& m_socket;
int m_client_id { -1 };
int m_client_pid { -1 };
};
} // Server
} // IPC
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