q3process_unix.cpp

奇趣公司比较新的qt/emd版本

/***********************************************************************
 *
 * Q3ProcessPrivate
 *
 **********************************************************************/
Q3ProcessManager *Q3ProcessPrivate::procManager = 0;

Q3ProcessPrivate::Q3ProcessPrivate()
{
#if defined(QT_Q3PROCESS_DEBUG)
    qDebug( "Q3ProcessPrivate: Constructor" );
#endif
    stdinBufRead = 0;

    notifierStdin = 0;
    notifierStdout = 0;
    notifierStderr = 0;

    exitValuesCalculated = false;
    socketReadCalled = false;

    proc = 0;
}

Q3ProcessPrivate::~Q3ProcessPrivate()
{
#if defined(QT_Q3PROCESS_DEBUG)
    qDebug( "Q3ProcessPrivate: Destructor" );
#endif

    if ( proc != 0 ) {
	if ( proc->socketStdin != 0 ) {
	    ::close( proc->socketStdin );
	    proc->socketStdin = 0;
	}
	proc->process = 0;
    }

    while ( !stdinBuf.isEmpty() ) {
	delete stdinBuf.dequeue();
    }
    delete notifierStdin;
    delete notifierStdout;
    delete notifierStderr;
}

/*
  Closes all open sockets in the child process that are not needed by the child
  process. Otherwise one child may have an open socket on standard input, etc.
  of another child.
*/
void Q3ProcessPrivate::closeOpenSocketsForChild()
{
    if ( procManager != 0 ) {
	if ( procManager->sigchldFd[0] != 0 )
	    ::close( procManager->sigchldFd[0] );
	if ( procManager->sigchldFd[1] != 0 )
	    ::close( procManager->sigchldFd[1] );

	// close also the sockets from other Q3Process instances
	for ( QProc *p=procManager->procList->first(); p!=0; p=procManager->procList->next() ) {
	    ::close( p->socketStdin );
	    ::close( p->socketStdout );
	    ::close( p->socketStderr );
	}
    }
}

void Q3ProcessPrivate::newProc( pid_t pid, Q3Process *process )
{
    proc = new QProc( pid, process );
    if ( procManager == 0 ) {
	procManager = new Q3ProcessManager;
	qAddPostRoutine(q3process_cleanup);
    }
    // the Q3ProcessManager takes care of deleting the QProc instances
    procManager->append( proc );
}

/***********************************************************************
 *
 * sigchld handler callback
 *
 **********************************************************************/
static QT_SIGNAL_RETTYPE qt_C_sigchldHnd(QT_SIGNAL_ARGS)
{
    if ( Q3ProcessPrivate::procManager == 0 )
	return;
    if ( Q3ProcessPrivate::procManager->sigchldFd[0] == 0 )
	return;

    char a = 1;
    ::write( Q3ProcessPrivate::procManager->sigchldFd[0], &a, sizeof(a) );
}


/***********************************************************************
 *
 * Q3Process
 *
 **********************************************************************/
/*
  This private class does basic initialization.
*/
void Q3Process::init()
{
    d = new Q3ProcessPrivate();
    exitStat = 0;
    exitNormal = false;
}

/*
  This private class resets the process variables, etc. so that it can be used
  for another process to start.
*/
void Q3Process::reset()
{
    delete d;
    d = new Q3ProcessPrivate();
    exitStat = 0;
    exitNormal = false;
    d->bufStdout.clear();
    d->bufStderr.clear();
}

Q3Membuf* Q3Process::membufStdout()
{
    if ( d->proc && d->proc->socketStdout ) {
	/*
	  Apparently, there is not consistency among different
	  operating systems on how to use FIONREAD.

	  FreeBSD, Linux and Solaris all expect the 3rd argument to
	  ioctl() to be an int, which is normally 32-bit even on
	  64-bit machines.

	  IRIX, on the other hand, expects a size_t, which is 64-bit
	  on 64-bit machines.

	  So, the solution is to use size_t initialized to zero to
	  make sure all bits are set to zero, preventing underflow
	  with the FreeBSD/Linux/Solaris ioctls.
	*/
	size_t nbytes = 0;
	if ( ::ioctl(d->proc->socketStdout, FIONREAD, (char*)&nbytes)==0 && nbytes>0 )
	    socketRead( d->proc->socketStdout );
    }
    return &d->bufStdout;
}

Q3Membuf* Q3Process::membufStderr()
{
    if ( d->proc && d->proc->socketStderr ) {
	/*
	  Apparently, there is not consistency among different
	  operating systems on how to use FIONREAD.

	  FreeBSD, Linux and Solaris all expect the 3rd argument to
	  ioctl() to be an int, which is normally 32-bit even on
	  64-bit machines.

	  IRIX, on the other hand, expects a size_t, which is 64-bit
	  on 64-bit machines.

	  So, the solution is to use size_t initialized to zero to
	  make sure all bits are set to zero, preventing underflow
	  with the FreeBSD/Linux/Solaris ioctls.
	*/
	size_t nbytes = 0;
	if ( ::ioctl(d->proc->socketStderr, FIONREAD, (char*)&nbytes)==0 && nbytes>0 )
	    socketRead( d->proc->socketStderr );
    }
    return &d->bufStderr;
}

/*!
    Destroys the instance.

    If the process is running, it is <b>not</b> terminated! The
    standard input, standard output and standard error of the process
    are closed.

    You can connect the destroyed() signal to the kill() slot, if you
    want the process to be terminated automatically when the instance
    is destroyed.

    \sa tryTerminate() kill()
*/
Q3Process::~Q3Process()
{
    delete d;
}

/*!
    Tries to run a process for the command and arguments that were
    specified with setArguments(), addArgument() or that were
    specified in the constructor. The command is searched for in the
    path for executable programs; you can also use an absolute path in
    the command itself.

    If \a env is null, then the process is started with the same
    environment as the starting process. If \a env is non-null, then
    the values in the stringlist are interpreted as environment
    setttings of the form \c {key=value} and the process is started in
    these environment settings. For convenience, there is a small
    exception to this rule: under Unix, if \a env does not contain any
    settings for the environment variable \c LD_LIBRARY_PATH, then
    this variable is inherited from the starting process; under
    Windows the same applies for the environment variable \c PATH.

    Returns true if the process could be started; otherwise returns
    false.

    You can write data to the process's standard input with
    writeToStdin(). You can close standard input with closeStdin() and
    you can terminate the process with tryTerminate(), or with kill().

    You can call this function even if you've used this instance to
    create a another process which is still running. In such cases,
    Q3Process closes the old process's standard input and deletes
    pending data, i.e., you lose all control over the old process, but
    the old process is not terminated. This applies also if the
    process could not be started. (On operating systems that have
    zombie processes, Qt will also wait() on the old process.)

    \sa launch() closeStdin()
*/
bool Q3Process::start( QStringList *env )
{
#if defined(QT_Q3PROCESS_DEBUG)
    qDebug( "Q3Process::start()" );
#endif
    reset();

    int sStdin[2];
    int sStdout[2];
    int sStderr[2];

    // open sockets for piping
#ifndef Q_OS_QNX6
    if ( (comms & Stdin) && ::socketpair( AF_UNIX, SOCK_STREAM, 0, sStdin ) == -1 ) {
#else
    if ( (comms & Stdin) && qnx6SocketPairReplacement(sStdin) == -1 ) {
#endif
	return false;
    }
#ifndef Q_OS_QNX6
    if ( (comms & Stderr) && ::socketpair( AF_UNIX, SOCK_STREAM, 0, sStderr ) == -1 ) {
#else
    if ( (comms & Stderr) && qnx6SocketPairReplacement(sStderr) == -1 ) {
#endif
	if ( comms & Stdin ) {
	    ::close( sStdin[0] );
	    ::close( sStdin[1] );
	}
	return false;
    }
#ifndef Q_OS_QNX6
    if ( (comms & Stdout) && ::socketpair( AF_UNIX, SOCK_STREAM, 0, sStdout ) == -1 ) {
#else
    if ( (comms & Stdout) && qnx6SocketPairReplacement(sStdout) == -1 ) {
#endif
	if ( comms & Stdin ) {
	    ::close( sStdin[0] );
	    ::close( sStdin[1] );
	}
	if ( comms & Stderr ) {
	    ::close( sStderr[0] );
	    ::close( sStderr[1] );
	}
	return false;
    }

    // the following pipe is only used to determine if the process could be
    // started
    int fd[2];
    if ( pipe( fd ) < 0 ) {
	// non critical error, go on
	fd[0] = 0;
	fd[1] = 0;
    }

    // construct the arguments for exec
    Q3CString *arglistQ = new Q3CString[ _arguments.count() + 1 ];
    const char** arglist = new const char*[ _arguments.count() + 1 ];
    int i = 0;
    for ( QStringList::Iterator it = _arguments.begin(); it != _arguments.end(); ++it ) {
	arglistQ[i] = (*it).local8Bit();
	arglist[i] = arglistQ[i];
#if defined(QT_Q3PROCESS_DEBUG)
	qDebug( "Q3Process::start(): arg %d = %s", i, arglist[i] );
#endif
	i++;
    }
#ifdef Q_OS_MACX
    if(i) {
	Q3CString arg_bundle = arglistQ[0];
	QFileInfo fi(QString::fromUtf8(arg_bundle.constData()));
	if(fi.exists() && fi.isDir() && arg_bundle.right(4) == ".app") {
	    Q3CString exe = arg_bundle;
	    int lslash = exe.findRev('/');
	    if(lslash != -1)
		exe = exe.mid(lslash+1);
	    exe = Q3CString(arg_bundle + "/Contents/MacOS/" + exe);
	    exe = exe.left(exe.length() - 4); //chop off the .app
	    if(QFile::exists(QString::fromLatin1(exe.constData()))) {
		arglistQ[0] = exe;
		arglist[0] = arglistQ[0];
	    }
	}
    }
#endif
    arglist[i] = 0;

    // Must make sure signal handlers are installed before exec'ing
    // in case the process exits quickly.
    if ( d->procManager == 0 ) {
	d->procManager = new Q3ProcessManager;
	qAddPostRoutine(q3process_cleanup);
    }

    // fork and exec
    QApplication::flushX();
    pid_t pid = fork();
    if ( pid == 0 ) {
	// child
	d->closeOpenSocketsForChild();
	if ( comms & Stdin ) {
	    ::close( sStdin[1] );
	    ::dup2( sStdin[0], STDIN_FILENO );
	}
	if ( comms & Stdout ) {
	    ::close( sStdout[0] );
	    ::dup2( sStdout[1], STDOUT_FILENO );
	}
	if ( comms & Stderr ) {
	    ::close( sStderr[0] );
	    ::dup2( sStderr[1], STDERR_FILENO );
	}
	if ( comms & DupStderr ) {
	    ::dup2( STDOUT_FILENO, STDERR_FILENO );
	}
#ifndef QT_NO_DIR
	::chdir( workingDir.absPath().latin1() );
#endif
	if ( fd[0] )
	    ::close( fd[0] );
	if ( fd[1] )
	    ::fcntl( fd[1], F_SETFD, FD_CLOEXEC ); // close on exec shows success

	if ( env == 0 ) { // inherit environment and start process
#ifndef Q_OS_QNX4
	    ::execvp( arglist[0], (char*const*)arglist ); // ### cast not nice
#else
	    ::execvp( arglist[0], (char const*const*)arglist ); // ### cast not nice
#endif
	} else { // start process with environment settins as specified in env
	    // construct the environment for exec
	    int numEntries = env->count();
#if defined(Q_OS_MACX)
	    QString ld_library_path(QLatin1String("DYLD_LIBRARY_PATH"));
#else
	    QString ld_library_path(QLatin1String("LD_LIBRARY_PATH"));
#endif
	    bool setLibraryPath =
		env->grep( QRegExp( QLatin1Char('^') + ld_library_path + QLatin1Char('=') ) ).empty() &&
		getenv( ld_library_path.local8Bit() ) != 0;
	    if ( setLibraryPath )
		numEntries++;
	    Q3CString *envlistQ = new Q3CString[ numEntries + 1 ];
	    const char** envlist = new const char*[ numEntries + 1 ];
	    int i = 0;
	    if ( setLibraryPath ) {
		envlistQ[i] = QString( ld_library_path + QLatin1String("=%1") ).arg( QString::fromLocal8Bit(getenv( ld_library_path.local8Bit() )) ).local8Bit();
		envlist[i] = envlistQ[i];
		i++;
	    }
	    for ( QStringList::Iterator it = env->begin(); it != env->end(); ++it ) {
		envlistQ[i] = (*it).local8Bit();
		envlist[i] = envlistQ[i];
		i++;
	    }
	    envlist[i] = 0;

	    // look for the executable in the search path
	    if ( _arguments.count()>0 && getenv("PATH")!=0 ) {
		QString command = _arguments[0];
		if ( !command.contains( QLatin1Char('/') ) ) {
		    QStringList pathList = QStringList::split( QLatin1Char(':'), QString::fromLocal8Bit(getenv( "PATH" )) );
		    for (QStringList::Iterator it = pathList.begin(); it != pathList.end(); ++it ) {
			QString dir = *it;
#if defined(Q_OS_MACX) //look in a bundle
			if(!QFile::exists(dir + QLatin1Char('/') + command) && QFile::exists(dir + QLatin1Char('/') + command + QLatin1String(".app")))
			    dir += QLatin1Char('/') + command + QLatin1String(".app/Contents/MacOS");
#endif
#ifndef QT_NO_DIR
			QFileInfo fileInfo( dir, command );
#else
			QFileInfo fileInfo( dir + "/" + command );
#endif
			if ( fileInfo.isExecutable() ) {
#if defined(Q_OS_MACX)
			    arglistQ[0] = fileInfo.absFilePath().local8Bit();
#else
			    arglistQ[0] = fileInfo.filePath().local8Bit();
#endif
			    arglist[0] = arglistQ[0];
			    break;
			}
		    }
		}
	    }
#ifndef Q_OS_QNX4
	    ::execve( arglist[0], (char*const*)arglist, (char*const*)envlist ); // ### casts not nice
#else
	    ::execve( arglist[0], (char const*const*)arglist,(char const*const*)envlist ); // ### casts not nice
#endif
	}
	if ( fd[1] ) {
	    char buf = 0;
	    ::write( fd[1], &buf, 1 );
	    ::close( fd[1] );
	}
	::_exit( -1 );
    } else if ( pid == -1 ) {
	// error forking
	goto error;
    }

    // test if exec was successful
    if ( fd[1] )
	::close( fd[1] );
    if ( fd[0] ) {
	char buf;
	for ( ;; ) {
	    int n = ::read( fd[0], &buf, 1 );
	    if ( n==1 ) {
		// socket was not closed => error
		if ( ::waitpid( pid, 0, WNOHANG ) != pid ) {
		    // The wait did not succeed yet, so try again when we get
		    // the sigchild (to avoid zombies).
		    d->newProc( pid, 0 );
		}
		d->proc = 0;
		goto error;
	    } else if ( n==-1 ) {
		if ( errno==EAGAIN || errno==EINTR )
		    // try it again
		    continue;
	    }
	    break;
	}
	::close( fd[0] );
    }

    d->newProc( pid, this );

    if ( comms & Stdin ) {
	::close( sStdin[0] );
	d->proc->socketStdin = sStdin[1];

	// Select non-blocking mode
	int originalFlags = fcntl(d->proc->socketStdin, F_GETFL, 0);
	fcntl(d->proc->socketStdin, F_SETFL, originalFlags | O_NONBLOCK);

	d->notifierStdin = new QSocketNotifier( sStdin[1], QSocketNotifier::Write );
	connect( d->notifierStdin, SIGNAL(activated(int)),