lyx_mirror/src/Server.cpp
Abdelrazak Younes c3e1c597ab MSVC compil fix.
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@20323 a592a061-630c-0410-9148-cb99ea01b6c8
2007-09-17 20:27:38 +00:00

526 lines
12 KiB
C++

/**
* \file Server.cpp
* This file is part of LyX, the document processor.
* Licence details can be found in the file COPYING.
*
* \author Lars Gullik Bjønnes
* \author Jean-Marc Lasgouttes
* \author Angus Leeming
* \author John Levon
*
* Full author contact details are available in file CREDITS.
*/
/**
Docu : To use the lyxserver define the name of the pipe in your
lyxrc:
\serverpipe "/home/myhome/.lyxpipe"
Then use .lyxpipe.in and .lyxpipe.out to communicate to LyX.
Each message consists of a single line in ASCII. Input lines
(client -> LyX) have the following format:
"LYXCMD:<clientname>:<functionname>:<argument>"
Answers from LyX look like this:
"INFO:<clientname>:<functionname>:<data>"
[asierra970531] Or like this in case of error:
"ERROR:<clientname>:<functionname>:<error message>"
where <clientname> and <functionname> are just echoed.
If LyX notifies about a user defined extension key-sequence,
the line looks like this:
"NOTIFY:<key-sequence>"
[asierra970531] New server-only messages to implement a simple protocol
"LYXSRV:<clientname>:<protocol message>"
where <protocol message> can be "hello" or "bye". If hello is
received LyX will inform the client that it's listening its
messages, and 'bye' will inform that lyx is closing.
See development/server_monitor.c for an example client.
Purpose: implement a client/server lib for LyX
*/
#include <config.h>
#include "Server.h"
#include "debug.h"
#include "FuncRequest.h"
#include "LyXAction.h"
#include "LyXFunc.h"
#include "frontends/Application.h"
#include "support/FileName.h"
#include "support/lstrings.h"
#include "support/lyxlib.h"
#include <boost/bind.hpp>
#include <cerrno>
#ifdef HAVE_SYS_STAT_H
# include <sys/stat.h>
#endif
#include <fcntl.h>
namespace lyx {
using support::compare;
using support::FileName;
using support::rtrim;
using support::split;
using support::unlink;
using std::endl;
using std::string;
/////////////////////////////////////////////////////////////////////
//
// LyXComm
//
/////////////////////////////////////////////////////////////////////
#if !defined (HAVE_MKFIFO)
// We provide a stub class that disables the lyxserver.
LyXComm::LyXComm(std::string const &, Server *, ClientCallbackfct)
{}
void LyXComm::openConnection()
{}
void LyXComm::closeConnection()
{}
int LyXComm::startPipe(string const & filename, bool write)
{
return -1;
}
void LyXComm::endPipe(int & fd, string const & filename, bool write)
{}
void LyXComm::emergencyCleanup()
{}
void LyXComm::read_ready()
{}
void LyXComm::send(string const & msg)
{}
#else // defined (HAVE_MKFIFO)
LyXComm::LyXComm(std::string const & pip, Server * cli, ClientCallbackfct ccb)
: pipename_(pip), client_(cli), clientcb_(ccb)
{
ready_ = false;
openConnection();
}
void LyXComm::openConnection()
{
LYXERR(Debug::LYXSERVER) << "LyXComm: Opening connection" << endl;
// If we are up, that's an error
if (ready_) {
lyxerr << "LyXComm: Already connected" << endl;
return;
}
// We assume that we don't make it
ready_ = false;
if (pipename_.empty()) {
LYXERR(Debug::LYXSERVER)
<< "LyXComm: server is disabled, nothing to do"
<< endl;
return;
}
infd_ = startPipe(inPipeName(), false);
if (infd_ == -1)
return;
outfd_ = startPipe(outPipeName(), true);
if (outfd_ == -1) {
endPipe(infd_, inPipeName(), false);
return;
}
if (fcntl(outfd_, F_SETFL, O_NONBLOCK) < 0) {
lyxerr << "LyXComm: Could not set flags on pipe " << outPipeName()
<< '\n' << strerror(errno) << endl;
return;
}
// We made it!
ready_ = true;
LYXERR(Debug::LYXSERVER) << "LyXComm: Connection established" << endl;
}
/// Close pipes
void LyXComm::closeConnection()
{
LYXERR(Debug::LYXSERVER) << "LyXComm: Closing connection" << endl;
if (pipename_.empty()) {
LYXERR(Debug::LYXSERVER)
<< "LyXComm: server is disabled, nothing to do"
<< endl;
return;
}
if (!ready_) {
lyxerr << "LyXComm: Already disconnected" << endl;
return;
}
endPipe(infd_, inPipeName(), false);
endPipe(outfd_, outPipeName(), true);
ready_ = false;
}
int LyXComm::startPipe(string const & file, bool write)
{
FileName const filename(file);
if (::access(filename.toFilesystemEncoding().c_str(), F_OK) == 0) {
lyxerr << "LyXComm: Pipe " << filename << " already exists.\n"
<< "If no other LyX program is active, please delete"
" the pipe by hand and try again." << endl;
pipename_.erase();
return -1;
}
if (::mkfifo(filename.toFilesystemEncoding().c_str(), 0600) < 0) {
lyxerr << "LyXComm: Could not create pipe " << filename << '\n'
<< strerror(errno) << endl;
return -1;
}
int const fd = ::open(filename.toFilesystemEncoding().c_str(),
write ? (O_RDWR) : (O_RDONLY|O_NONBLOCK));
if (fd < 0) {
lyxerr << "LyXComm: Could not open pipe " << filename << '\n'
<< strerror(errno) << endl;
unlink(filename);
return -1;
}
if (!write) {
theApp()->registerSocketCallback(fd,
boost::bind(&LyXComm::read_ready, this));
}
return fd;
}
void LyXComm::endPipe(int & fd, string const & filename, bool write)
{
if (fd < 0)
return;
if (!write)
theApp()->unregisterSocketCallback(fd);
if (::close(fd) < 0) {
lyxerr << "LyXComm: Could not close pipe " << filename
<< '\n' << strerror(errno) << endl;
}
if (unlink(FileName(filename)) < 0) {
lyxerr << "LyXComm: Could not remove pipe " << filename
<< '\n' << strerror(errno) << endl;
}
fd = -1;
}
void LyXComm::emergencyCleanup()
{
if (!pipename_.empty()) {
endPipe(infd_, inPipeName(), false);
endPipe(outfd_, outPipeName(), true);
}
}
// Receives messages and sends then to client
void LyXComm::read_ready()
{
// FIXME: make read_buffer_ a class-member for multiple sessions
static string read_buffer_;
read_buffer_.erase();
int const charbuf_size = 100;
char charbuf[charbuf_size];
errno = 0;
int status;
// the single = is intended here.
while ((status = ::read(infd_, charbuf, charbuf_size - 1))) {
if (status > 0) {
charbuf[status] = '\0'; // turn it into a c string
read_buffer_ += rtrim(charbuf, "\r");
// commit any commands read
while (read_buffer_.find('\n') != string::npos) {
// split() grabs the entire string if
// the delim /wasn't/ found. ?:-P
string cmd;
read_buffer_= split(read_buffer_, cmd,'\n');
LYXERR(Debug::LYXSERVER)
<< "LyXComm: status:" << status
<< ", read_buffer_:" << read_buffer_
<< ", cmd:" << cmd << endl;
if (!cmd.empty())
clientcb_(client_, cmd);
//\n or not \n?
}
}
if (errno == EAGAIN) {
errno = 0;
return;
}
if (errno != 0) {
lyxerr << "LyXComm: " << strerror(errno) << endl;
if (!read_buffer_.empty()) {
lyxerr << "LyXComm: truncated command: "
<< read_buffer_ << endl;
read_buffer_.erase();
}
break; // reset connection
}
}
// The connection gets reset in errno != EAGAIN
// Why does it need to be reset if errno == 0?
closeConnection();
openConnection();
errno = 0;
}
void LyXComm::send(string const & msg)
{
if (msg.empty()) {
lyxerr << "LyXComm: Request to send empty string. Ignoring."
<< endl;
return;
}
LYXERR(Debug::LYXSERVER) << "LyXComm: Sending '" << msg << '\'' << endl;
if (pipename_.empty()) return;
if (!ready_) {
lyxerr << "LyXComm: Pipes are closed. Could not send "
<< msg << endl;
} else if (::write(outfd_, msg.c_str(), msg.length()) < 0) {
lyxerr << "LyXComm: Error sending message: " << msg
<< '\n' << strerror(errno)
<< "\nLyXComm: Resetting connection" << endl;
closeConnection();
openConnection();
}
}
#endif // defined (HAVE_MKFIFO)
string const LyXComm::inPipeName() const
{
return pipename_ + ".in";
}
string const LyXComm::outPipeName() const
{
return pipename_ + ".out";
}
/////////////////////////////////////////////////////////////////////
//
// Server
//
/////////////////////////////////////////////////////////////////////
void ServerCallback(Server * server, string const & msg)
{
server->callback(msg);
}
Server::Server(LyXFunc * f, std::string const & pipes)
: numclients_(0), func_(f), pipes_(pipes, this, &ServerCallback)
{}
Server::~Server()
{
// say goodbye to clients so they stop sending messages
// send as many bye messages as there are clients,
// each with client's name.
string message;
for (int i = 0; i != numclients_; ++i) {
message = "LYXSRV:" + clients_[i] + ":bye\n";
pipes_.send(message);
}
}
// Handle data gotten from communication, called by LyXComm
void Server::callback(string const & msg)
{
LYXERR(Debug::LYXSERVER) << "Server: Received: '"
<< msg << '\'' << endl;
char const * p = msg.c_str();
// --- parse the string --------------------------------------------
//
// Format: LYXCMD:<client>:<func>:<argstring>\n
//
bool server_only = false;
while (*p) {
// --- 1. check 'header' ---
if (compare(p, "LYXSRV:", 7) == 0) {
server_only = true;
} else if (0 != compare(p, "LYXCMD:", 7)) {
lyxerr << "Server: Unknown request \""
<< p << '"' << endl;
return;
}
p += 7;
// --- 2. for the moment ignore the client name ---
string client;
while (*p && *p != ':')
client += char(*p++);
if (*p == ':')
++p;
if (!*p)
return;
// --- 3. get function name ---
string cmd;
while (*p && *p != ':')
cmd += char(*p++);
// --- 4. parse the argument ---
string arg;
if (!server_only && *p == ':' && *(++p)) {
while (*p && *p != '\n')
arg += char(*p++);
if (*p) ++p;
}
LYXERR(Debug::LYXSERVER)
<< "Server: Client: '" << client
<< "' Command: '" << cmd
<< "' Argument: '" << arg << '\'' << endl;
// --- lookup and exec the command ------------------
if (server_only) {
string buf;
// return the greeting to inform the client that
// we are listening.
if (cmd == "hello") {
// One more client
if (numclients_ == MAX_CLIENTS) { //paranoid check
LYXERR(Debug::LYXSERVER)
<< "Server: too many clients..."
<< endl;
return;
}
int i = 0;
while (!clients_[i].empty() && i < numclients_)
++i;
clients_[i] = client;
++numclients_;
buf = "LYXSRV:" + client + ":hello\n";
LYXERR(Debug::LYXSERVER)
<< "Server: Greeting "
<< client << endl;
pipes_.send(buf);
} else if (cmd == "bye") {
// If clients_ == 0 maybe we should reset the pipes
// to prevent fake callbacks
int i = 0; //look if client is registered
for (; i < numclients_; ++i) {
if (clients_[i] == client)
break;
}
if (i < numclients_) {
--numclients_;
clients_[i].erase();
LYXERR(Debug::LYXSERVER)
<< "Server: Client "
<< client << " said goodbye"
<< endl;
} else {
LYXERR(Debug::LYXSERVER)
<< "Server: ignoring bye messge from unregistered client"
<< client << endl;
}
} else {
lyxerr <<"Server: Undefined server command "
<< cmd << '.' << endl;
}
return;
}
if (!cmd.empty()) {
// which lyxfunc should we let it connect to?
// The correct solution would be to have a
// specialized (non-gui) BufferView. But how do
// we do it now? Probably we should just let it
// connect to the lyxfunc in the single LyXView we
// support currently. (Lgb)
func_->dispatch(FuncRequest(lyxaction.lookupFunc(cmd), arg));
string const rval = to_utf8(func_->getMessage());
// all commands produce an INFO or ERROR message
// in the output pipe, even if they do not return
// anything. See chapter 4 of Customization doc.
string buf;
if (func_->errorStat())
buf = "ERROR:";
else
buf = "INFO:";
buf += client + ':' + cmd + ':' + rval + '\n';
pipes_.send(buf);
// !!! we don't do any error checking -
// if the client won't listen, the
// message is lost and others too
// maybe; so the client should empty
// the outpipe before issuing a request.
// not found
}
} // while *p
}
// Send a notify messge to a client, called by WorkAreaKeyPress
void Server::notifyClient(string const & s)
{
pipes_.send("NOTIFY:" + s + "\n");
}
} // namespace lyx