kakoune/src/remote.cc
2017-03-07 01:12:37 +00:00

798 lines
22 KiB
C++

#include "remote.hh"
#include "buffer_manager.hh"
#include "buffer_utils.hh"
#include "client_manager.hh"
#include "command_manager.hh"
#include "display_buffer.hh"
#include "event_manager.hh"
#include "file.hh"
#include "hash_map.hh"
#include "optional.hh"
#include "user_interface.hh"
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/wait.h>
#include <unistd.h>
#include <pwd.h>
#include <fcntl.h>
namespace Kakoune
{
enum class MessageType : char
{
Unknown,
Connect,
Command,
MenuShow,
MenuSelect,
MenuHide,
InfoShow,
InfoHide,
Draw,
DrawStatus,
Refresh,
SetOptions,
Key
};
class MsgWriter
{
public:
MsgWriter(RemoteBuffer& buffer, MessageType type)
: m_buffer{buffer}, m_start{(uint32_t)buffer.size()}
{
write(type);
write((uint32_t)0); // message size, to be patched on write
}
~MsgWriter() noexcept(false)
{
uint32_t count = (uint32_t)m_buffer.size() - m_start;
*reinterpret_cast<uint32_t*>(m_buffer.data() + m_start + 1) = count;
}
void write(const char* val, size_t size)
{
m_buffer.insert(m_buffer.end(), val, val + size);
}
template<typename T>
void write(const T& val)
{
write((const char*)&val, sizeof(val));
}
void write(StringView str)
{
write(str.length());
write(str.data(), (int)str.length());
};
void write(const String& str)
{
write(StringView{str});
}
template<typename T>
void write(ConstArrayView<T> view)
{
write<uint32_t>(view.size());
for (auto& val : view)
write(val);
}
template<typename T, MemoryDomain domain>
void write(const Vector<T, domain>& vec)
{
write(ConstArrayView<T>(vec));
}
template<typename Key, typename Val, MemoryDomain domain>
void write(const HashMap<Key, Val, domain>& map)
{
write<uint32_t>(map.size());
for (auto& val : map)
{
write(val.key);
write(val.value);
}
}
template<typename T>
void write(const Optional<T>& val)
{
write((bool)val);
if (val)
write(*val);
}
void write(Color color)
{
write(color.color);
if (color.color == Color::RGB)
{
write(color.r);
write(color.g);
write(color.b);
}
}
void write(const DisplayAtom& atom)
{
write(atom.content());
write(atom.face);
}
void write(const DisplayLine& line)
{
write(line.atoms());
}
void write(const DisplayBuffer& display_buffer)
{
write(display_buffer.lines());
}
private:
RemoteBuffer& m_buffer;
uint32_t m_start;
};
class MsgReader
{
public:
void read_available(int sock)
{
if (m_write_pos < header_size)
{
m_stream.resize(header_size);
read_from_socket(sock, header_size - m_write_pos);
if (m_write_pos == header_size)
{
if (size() < header_size)
throw disconnected{"invalid message received"};
m_stream.resize(size());
}
}
else
read_from_socket(sock, size() - m_write_pos);
}
bool ready() const
{
return m_write_pos >= header_size and m_write_pos == size();
}
uint32_t size() const
{
kak_assert(m_write_pos >= header_size);
return *reinterpret_cast<const uint32_t*>(m_stream.data()+1);
}
MessageType type() const
{
kak_assert(m_write_pos >= header_size);
return *reinterpret_cast<const MessageType*>(m_stream.data());
}
void read(char* buffer, size_t size)
{
if (m_read_pos + size > m_stream.size())
throw disconnected{"tried to read after message end"};
memcpy(buffer, m_stream.data() + m_read_pos, size);
m_read_pos += size;
}
template<typename T>
T read()
{
union U
{
T object;
alignas(T) char data[sizeof(T)];
U() {};
~U() { object.~T(); }
} u;
read(u.data, sizeof(T));
return u.object;
}
template<typename T>
Vector<T> read_vector()
{
uint32_t size = read<uint32_t>();
Vector<T> res;
res.reserve(size);
while (size--)
res.push_back(read<T>());
return res;
}
template<typename Key, typename Val, MemoryDomain domain>
HashMap<Key, Val, domain> read_hash_map()
{
uint32_t size = read<uint32_t>();
HashMap<Key, Val, domain> res;
res.reserve(size);
while (size--)
{
auto key = read<Key>();
auto val = read<Val>();
res.insert({std::move(key), std::move(val)});
}
return res;
}
template<typename T>
Optional<T> read_optional()
{
if (not read<bool>())
return {};
return read<T>();
}
void reset()
{
m_stream.resize(0);
m_write_pos = 0;
m_read_pos = header_size;
}
private:
void read_from_socket(int sock, size_t size)
{
kak_assert(m_write_pos + size <= m_stream.size());
int res = ::read(sock, m_stream.data() + m_write_pos, size);
if (res <= 0)
throw disconnected{res ? format("socket read failed: {}", strerror(errno))
: "peer disconnected", res == 0};
m_write_pos += res;
}
static constexpr uint32_t header_size = sizeof(MessageType) + sizeof(uint32_t);
Vector<char, MemoryDomain::Remote> m_stream;
uint32_t m_write_pos = 0;
uint32_t m_read_pos = header_size;
};
template<>
String MsgReader::read<String>()
{
ByteCount length = read<ByteCount>();
String res;
if (length > 0)
{
res.force_size((int)length);
read(&res[0_byte], (int)length);
}
return res;
}
template<>
Color MsgReader::read<Color>()
{
Color res;
res.color = read<Color::NamedColor>();
if (res.color == Color::RGB)
{
res.r = read<unsigned char>();
res.g = read<unsigned char>();
res.b = read<unsigned char>();
}
return res;
}
template<>
DisplayAtom MsgReader::read<DisplayAtom>()
{
DisplayAtom atom(read<String>());
atom.face = read<Face>();
return atom;
}
template<>
DisplayLine MsgReader::read<DisplayLine>()
{
return DisplayLine(read_vector<DisplayAtom>());
}
template<>
DisplayBuffer MsgReader::read<DisplayBuffer>()
{
DisplayBuffer db;
db.lines() = read_vector<DisplayLine>();
return db;
}
class RemoteUI : public UserInterface
{
public:
RemoteUI(int socket, DisplayCoord dimensions);
~RemoteUI() override;
void menu_show(ConstArrayView<DisplayLine> choices,
DisplayCoord anchor, Face fg, Face bg,
MenuStyle style) override;
void menu_select(int selected) override;
void menu_hide() override;
void info_show(StringView title, StringView content,
DisplayCoord anchor, Face face,
InfoStyle style) override;
void info_hide() override;
void draw(const DisplayBuffer& display_buffer,
const Face& default_face,
const Face& padding_face) override;
void draw_status(const DisplayLine& status_line,
const DisplayLine& mode_line,
const Face& default_face) override;
void refresh(bool force) override;
DisplayCoord dimensions() override { return m_dimensions; }
void set_on_key(OnKeyCallback callback) override
{ m_on_key = std::move(callback); }
void set_ui_options(const Options& options) override;
void set_client(Client* client) { m_client = client; }
Client* client() const { return m_client.get(); }
private:
FDWatcher m_socket_watcher;
MsgReader m_reader;
DisplayCoord m_dimensions;
OnKeyCallback m_on_key;
RemoteBuffer m_send_buffer;
SafePtr<Client> m_client;
};
static bool send_data(int fd, RemoteBuffer& buffer)
{
while (buffer.size() > 0 and fd_writable(fd))
{
int res = ::write(fd, buffer.data(), buffer.size());
if (res <= 0)
throw disconnected{res ? format("socket write failed: {}", strerror(errno))
: "peer disconnected", res == 0};
buffer.erase(buffer.begin(), buffer.begin() + res);
}
return buffer.empty();
}
RemoteUI::RemoteUI(int socket, DisplayCoord dimensions)
: m_socket_watcher(socket, FdEvents::Read | FdEvents::Write,
[this](FDWatcher& watcher, FdEvents events, EventMode mode) {
const int sock = watcher.fd();
try
{
if (events & FdEvents::Write and send_data(sock, m_send_buffer))
m_socket_watcher.events() &= ~FdEvents::Write;
while (events & FdEvents::Read and fd_readable(sock))
{
m_reader.read_available(sock);
if (not m_reader.ready())
continue;
if (m_reader.type() != MessageType::Key)
{
ClientManager::instance().remove_client(*m_client, false);
return;
}
auto key = m_reader.read<Key>();
m_reader.reset();
if (key.modifiers == Key::Modifiers::Resize)
m_dimensions = key.coord();
m_on_key(key);
}
}
catch (const disconnected& err)
{
write_to_debug_buffer(format("Error while transfering remote messages: {}", err.what()));
ClientManager::instance().remove_client(*m_client, false);
}
}),
m_dimensions(dimensions)
{
write_to_debug_buffer(format("remote client connected: {}", m_socket_watcher.fd()));
}
RemoteUI::~RemoteUI()
{
write_to_debug_buffer(format("remote client disconnected: {}", m_socket_watcher.fd()));
m_socket_watcher.close_fd();
}
void RemoteUI::menu_show(ConstArrayView<DisplayLine> choices,
DisplayCoord anchor, Face fg, Face bg,
MenuStyle style)
{
MsgWriter msg{m_send_buffer, MessageType::MenuShow};
msg.write(choices);
msg.write(anchor);
msg.write(fg);
msg.write(bg);
msg.write(style);
m_socket_watcher.events() |= FdEvents::Write;
}
void RemoteUI::menu_select(int selected)
{
MsgWriter msg{m_send_buffer, MessageType::MenuSelect};
msg.write(selected);
m_socket_watcher.events() |= FdEvents::Write;
}
void RemoteUI::menu_hide()
{
MsgWriter msg{m_send_buffer, MessageType::MenuHide};
m_socket_watcher.events() |= FdEvents::Write;
}
void RemoteUI::info_show(StringView title, StringView content,
DisplayCoord anchor, Face face,
InfoStyle style)
{
MsgWriter msg{m_send_buffer, MessageType::InfoShow};
msg.write(title);
msg.write(content);
msg.write(anchor);
msg.write(face);
msg.write(style);
m_socket_watcher.events() |= FdEvents::Write;
}
void RemoteUI::info_hide()
{
MsgWriter msg{m_send_buffer, MessageType::InfoHide};
m_socket_watcher.events() |= FdEvents::Write;
}
void RemoteUI::draw(const DisplayBuffer& display_buffer,
const Face& default_face,
const Face& padding_face)
{
MsgWriter msg{m_send_buffer, MessageType::Draw};
msg.write(display_buffer);
msg.write(default_face);
msg.write(padding_face);
m_socket_watcher.events() |= FdEvents::Write;
}
void RemoteUI::draw_status(const DisplayLine& status_line,
const DisplayLine& mode_line,
const Face& default_face)
{
MsgWriter msg{m_send_buffer, MessageType::DrawStatus};
msg.write(status_line);
msg.write(mode_line);
msg.write(default_face);
m_socket_watcher.events() |= FdEvents::Write;
}
void RemoteUI::refresh(bool force)
{
MsgWriter msg{m_send_buffer, MessageType::Refresh};
msg.write(force);
m_socket_watcher.events() |= FdEvents::Write;
}
void RemoteUI::set_ui_options(const Options& options)
{
MsgWriter msg{m_send_buffer, MessageType::SetOptions};
msg.write(options);
m_socket_watcher.events() |= FdEvents::Write;
}
static sockaddr_un session_addr(StringView session)
{
sockaddr_un addr;
addr.sun_family = AF_UNIX;
if (find(session, '/')!= session.end())
format_to(addr.sun_path, "{}/kakoune/{}", tmpdir(), session);
else
format_to(addr.sun_path, "{}/kakoune/{}/{}", tmpdir(),
getpwuid(geteuid())->pw_name, session);
return addr;
}
static int connect_to(StringView session)
{
int sock = socket(AF_UNIX, SOCK_STREAM, 0);
fcntl(sock, F_SETFD, FD_CLOEXEC);
sockaddr_un addr = session_addr(session);
if (connect(sock, (sockaddr*)&addr, sizeof(addr.sun_path)) == -1)
throw disconnected(format("connect to {} failed", addr.sun_path));
return sock;
}
bool check_session(StringView session)
{
int sock = socket(AF_UNIX, SOCK_STREAM, 0);
auto close_sock = on_scope_end([sock]{ close(sock); });
sockaddr_un addr = session_addr(session);
return connect(sock, (sockaddr*)&addr, sizeof(addr.sun_path)) != -1;
}
RemoteClient::RemoteClient(StringView session, std::unique_ptr<UserInterface>&& ui,
const EnvVarMap& env_vars, StringView init_command,
Optional<BufferCoord> init_coord)
: m_ui(std::move(ui))
{
int sock = connect_to(session);
{
MsgWriter msg{m_send_buffer, MessageType::Connect};
msg.write(init_command);
msg.write(init_coord);
msg.write(m_ui->dimensions());
msg.write(env_vars);
}
m_ui->set_on_key([this](Key key){
MsgWriter msg(m_send_buffer, MessageType::Key);
msg.write(key);
m_socket_watcher->events() |= FdEvents::Write;
});
MsgReader reader;
m_socket_watcher.reset(new FDWatcher{sock, FdEvents::Read | FdEvents::Write,
[this, reader](FDWatcher& watcher, FdEvents events, EventMode) mutable {
const int sock = watcher.fd();
if (events & FdEvents::Write and send_data(sock, m_send_buffer))
m_socket_watcher->events() &= ~FdEvents::Write;
while (events & FdEvents::Read and
not reader.ready() and fd_readable(sock))
{
reader.read_available(sock);
if (not reader.ready())
continue;
auto clear_reader = on_scope_end([&reader] { reader.reset(); });
switch (reader.type())
{
case MessageType::MenuShow:
{
auto choices = reader.read_vector<DisplayLine>();
auto anchor = reader.read<DisplayCoord>();
auto fg = reader.read<Face>();
auto bg = reader.read<Face>();
auto style = reader.read<MenuStyle>();
m_ui->menu_show(choices, anchor, fg, bg, style);
break;
}
case MessageType::MenuSelect:
m_ui->menu_select(reader.read<int>());
break;
case MessageType::MenuHide:
m_ui->menu_hide();
break;
case MessageType::InfoShow:
{
auto title = reader.read<String>();
auto content = reader.read<String>();
auto anchor = reader.read<DisplayCoord>();
auto face = reader.read<Face>();
auto style = reader.read<InfoStyle>();
m_ui->info_show(title, content, anchor, face, style);
break;
}
case MessageType::InfoHide:
m_ui->info_hide();
break;
case MessageType::Draw:
{
auto display_buffer = reader.read<DisplayBuffer>();
auto default_face = reader.read<Face>();
auto padding_face = reader.read<Face>();
m_ui->draw(display_buffer, default_face, padding_face);
break;
}
case MessageType::DrawStatus:
{
auto status_line = reader.read<DisplayLine>();
auto mode_line = reader.read<DisplayLine>();
auto default_face = reader.read<Face>();
m_ui->draw_status(status_line, mode_line, default_face);
break;
}
case MessageType::Refresh:
m_ui->refresh(reader.read<bool>());
break;
case MessageType::SetOptions:
m_ui->set_ui_options(reader.read_hash_map<String, String, MemoryDomain::Options>());
break;
default:
kak_assert(false);
}
}
}});
}
void send_command(StringView session, StringView command)
{
int sock = connect_to(session);
auto close_sock = on_scope_end([sock]{ close(sock); });
RemoteBuffer buffer;
{
MsgWriter msg{buffer, MessageType::Command};
msg.write(command);
}
write(sock, {buffer.data(), buffer.data() + buffer.size()});
}
// A client accepter handle a connection until it closes or a nul byte is
// recieved. Everything recieved before is considered to be a command.
//
// * When a nul byte is recieved, the socket is handed to a new Client along
// with the command.
// * When the connection is closed, the command is run in an empty context.
class Server::Accepter
{
public:
Accepter(int socket)
: m_socket_watcher(socket, FdEvents::Read,
[this](FDWatcher&, FdEvents, EventMode mode) {
if (mode == EventMode::Normal)
handle_available_input();
})
{}
private:
void handle_available_input()
{
const int sock = m_socket_watcher.fd();
try
{
while (not m_reader.ready() and fd_readable(sock))
m_reader.read_available(sock);
if (not m_reader.ready())
return;
switch (m_reader.type())
{
case MessageType::Connect:
{
auto init_cmds = m_reader.read<String>();
auto init_coord = m_reader.read_optional<BufferCoord>();
auto dimensions = m_reader.read<DisplayCoord>();
auto env_vars = m_reader.read_hash_map<String, String, MemoryDomain::EnvVars>();
auto* ui = new RemoteUI{sock, dimensions};
if (auto* client = ClientManager::instance().create_client(
std::unique_ptr<UserInterface>(ui),
std::move(env_vars), init_cmds, init_coord))
ui->set_client(client);
Server::instance().remove_accepter(this);
break;
}
case MessageType::Command:
{
auto command = m_reader.read<String>();
if (not command.empty()) try
{
Context context{Context::EmptyContextFlag{}};
CommandManager::instance().execute(command, context);
}
catch (const runtime_error& e)
{
write_to_debug_buffer(format("error running command '{}': {}",
command, e.what()));
}
close(sock);
Server::instance().remove_accepter(this);
break;
}
default:
write_to_debug_buffer("Invalid introduction message received");
close(sock);
Server::instance().remove_accepter(this);
}
}
catch (const disconnected& err)
{
write_to_debug_buffer(format("accepting connection failed: {}", err.what()));
close(sock);
Server::instance().remove_accepter(this);
}
}
FDWatcher m_socket_watcher;
MsgReader m_reader;
};
Server::Server(String session_name)
: m_session{std::move(session_name)}
{
int listen_sock = socket(AF_UNIX, SOCK_STREAM, 0);
fcntl(listen_sock, F_SETFD, FD_CLOEXEC);
sockaddr_un addr = session_addr(m_session);
// set sticky bit on the shared kakoune directory
make_directory(format("{}/kakoune", tmpdir()), 01777);
make_directory(split_path(addr.sun_path).first, 0711);
// Do not give any access to the socket to other users by default
auto old_mask = umask(0077);
auto restore_mask = on_scope_end([old_mask]() { umask(old_mask); });
if (bind(listen_sock, (sockaddr*) &addr, sizeof(sockaddr_un)) == -1)
throw runtime_error(format("unable to bind listen socket '{}': {}",
addr.sun_path, strerror(errno)));
if (listen(listen_sock, 4) == -1)
throw runtime_error(format("unable to listen on socket '{}': {}",
addr.sun_path, strerror(errno)));
auto accepter = [this](FDWatcher& watcher, FdEvents, EventMode mode) {
sockaddr_un client_addr;
socklen_t client_addr_len = sizeof(sockaddr_un);
int sock = accept(watcher.fd(), (sockaddr*) &client_addr,
&client_addr_len);
if (sock == -1)
throw runtime_error("accept failed");
fcntl(sock, F_SETFD, FD_CLOEXEC);
m_accepters.emplace_back(new Accepter{sock});
};
m_listener.reset(new FDWatcher{listen_sock, FdEvents::Read, accepter});
}
bool Server::rename_session(StringView name)
{
String old_socket_file = format("{}/kakoune/{}/{}", tmpdir(),
getpwuid(geteuid())->pw_name, m_session);
String new_socket_file = format("{}/kakoune/{}/{}", tmpdir(),
getpwuid(geteuid())->pw_name, name);
if (rename(old_socket_file.c_str(), new_socket_file.c_str()) != 0)
return false;
m_session = name.str();
return true;
}
void Server::close_session(bool do_unlink)
{
if (do_unlink)
{
String socket_file = format("{}/kakoune/{}/{}", tmpdir(),
getpwuid(geteuid())->pw_name, m_session);
unlink(socket_file.c_str());
}
m_listener->close_fd();
m_listener.reset();
}
Server::~Server()
{
if (m_listener)
close_session();
}
void Server::remove_accepter(Accepter* accepter)
{
auto it = find(m_accepters, accepter);
kak_assert(it != m_accepters.end());
m_accepters.erase(it);
}
}