replaced the simple fork and execv method of starting applications with a

more sophisticated method (mostly taken from K/OProcess, because we can't
use libopie in libqpe).
We can detect now, if apps can not be started.

1 files changed, 54 insertions, 11 deletions

diff --git a/library/global.cpp b/library/global.cpp
index d6ba84f..68a3a75 100644
--- a/library/global.cpp
+++ b/library/global.cpp
@@ -1,140 +1,141 @@
 /**********************************************************************
 ** Copyright (C) 2000-2002 Trolltech AS.  All rights reserved.
 **
 ** This file is part of the Qtopia Environment.
 **
 ** This file may be distributed and/or modified under the terms of the
 ** GNU General Public License version 2 as published by the Free Software
 ** Foundation and appearing in the file LICENSE.GPL included in the
 ** packaging of this file.
 **
 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 **
 ** See http://www.trolltech.com/gpl/ for GPL licensing information.
 **
 ** Contact info@trolltech.com if any conditions of this licensing are
 ** not clear to you.
 **
 **********************************************************************/
 #define QTOPIA_INTERNAL_LANGLIST
 #include <qpe/qpedebug.h>
 #include <qpe/global.h>
 #include <qpe/qdawg.h>
 #include <qpe/qpeapplication.h>
 #include <qpe/resource.h>
 #include <qpe/storage.h>
 #include <qpe/applnk.h>
 #include <qpe/qcopenvelope_qws.h>
 
 #include <qfile.h>
 #include <qlabel.h>
 #include <qtimer.h>
 #include <qmap.h>
 #include <qdict.h>
 #include <qdir.h>
 #include <qmessagebox.h>
 #include <qregexp.h>
 
 #include <stdlib.h>
 #include <sys/stat.h>
 #include <sys/wait.h>
 #include <sys/types.h>
 #include <fcntl.h>
 #include <unistd.h>
+#include <errno.h>
 
 #include <qwindowsystem_qws.h> // for qwsServer
 #include <qdatetime.h>
 
 #include <qfile.h>
 
 namespace {
   // checks if the storage should be searched
   bool checkStorage(const QString &path ){ // this is a small Config replacement cause config is too limited -zecke
     QFile file(path );
     if(!file.open(IO_ReadOnly ) )
        return true;
 
     QByteArray array = file.readAll();
     QStringList list = QStringList::split('\n', QString( array ) );
     for(QStringList::Iterator it = list.begin(); it != list.end(); ++it ){
       if( (*it).startsWith("autocheck = 0" ) ){
         return false;
       }else if( (*it).startsWith("autocheck = 1" ) ){
         return true;
       }
     }
     return true;
   }
 }
 
 //#include "quickexec_p.h"
 
 class Emitter : public QObject {
     Q_OBJECT
 public:
     Emitter( QWidget* receiver, const QString& document )
     {
         connect(this, SIGNAL(setDocument(const QString&)),
             receiver, SLOT(setDocument(const QString&)));
         emit setDocument(document);
         disconnect(this, SIGNAL(setDocument(const QString&)),
                receiver, SLOT(setDocument(const QString&)));
     }
 
 signals:
     void setDocument(const QString&);
 };
 
 
 class StartingAppList : public QObject {
     Q_OBJECT
 public:
     static void add( const QString& name );
     static bool isStarting( const QString name );
 private slots:
     void handleNewChannel( const QString &);
 private:
     StartingAppList( QObject *parent=0, const char* name=0 ) ;
 
     QDict<QTime> dict;
     static StartingAppList *appl;
 };
 
 StartingAppList* StartingAppList::appl = 0;
 
 StartingAppList::StartingAppList( QObject *parent, const char* name )
     :QObject( parent, name )
 {
 #if QT_VERSION >= 232 && defined(QWS)
     connect( qwsServer, SIGNAL( newChannel(const QString&)),
              this, SLOT( handleNewChannel(const QString&)) );
         #endif     
     dict.setAutoDelete( TRUE );
 }
 
 void StartingAppList::add( const QString& name )
 {
 #if QT_VERSION >= 232  && !defined(QT_NO_COP)
     if ( !appl )
         appl = new StartingAppList;
     QTime *t = new QTime;
     t->start();
     appl->dict.insert( "QPE/Application/" + name, t );
 #endif
 }
 
 bool StartingAppList::isStarting( const QString name )
 {
 #if QT_VERSION >= 232  && !defined(QT_NO_COP)
     if ( appl ) {
         QTime *t  = appl->dict.find( "QPE/Application/" + name );
         if ( !t )
             return FALSE;
         if ( t->elapsed() > 10000 ) {
             // timeout in case of crash or something
             appl->dict.remove( "QPE/Application/" + name );
             return FALSE;
         }
         return TRUE;
     }
@@ -510,204 +511,246 @@ void Global::setDocument( QWidget* receiver, const QString& document )
     Emitter emitter(receiver,document);
 }
 
 /*!
   \internal
 */
 bool Global::terminateBuiltin( const QString& n )
 {
     if (!builtin)
         return FALSE;
     for (int i = 0; builtin[i].file; i++) {
         if ( builtin[i].file == n ) {
             delete running[i];
             return TRUE;
         }
     }
     return FALSE;
 }
 
 /*!
   \internal
 */
 void Global::terminate( const AppLnk* app )
 {
     //if ( terminateBuiltin(app->exec()) ) return; // maybe? haven't tried this
 
 #ifndef QT_NO_COP
     QCString channel = "QPE/Application/" + app->exec().utf8();
     if ( QCopChannel::isRegistered(channel) ) {
         QCopEnvelope e(channel, "quit()");
     }
 #endif
 }
 
 /*!
   Low-level function to run command \a c.
 
   \warning Do not use this function. Use execute instead.
 
   \sa execute()
 */
 void Global::invoke(const QString &c)
 {
     // Convert the command line in to a list of arguments
     QStringList list = QStringList::split(QRegExp("  *"),c);
 
 #if !defined(QT_NO_COP)
     QString ap=list[0];
     // see if the application is already running
     // XXX should lock file /tmp/qcop-msg-ap
     if ( QCopChannel::isRegistered( ("QPE/Application/" + ap).latin1() ) ) {
         // If the channel is already register, the app is already running, so show it.
         { QCopEnvelope env( ("QPE/Application/" + ap).latin1(), "raise()" ); }
                 
         QCopEnvelope e("QPE/System", "notBusy(QString)" );
         e << ap;
         return;
     }
     // XXX should unlock file /tmp/qcop-msg-ap
     //see if it is being started
     if ( StartingAppList::isStarting( ap ) ) {
         QCopEnvelope e("QPE/System", "notBusy(QString)" );
         e << ap;
         return;
     }
 
 #endif
 
 #ifdef QT_NO_QWS_MULTIPROCESS
     QMessageBox::warning( 0, "Error", "Could not find the application " + c, "Ok", 0, 0, 0, 1 );
 #else
 
     QStrList slist;
     unsigned int j;
     for ( j = 0; j < list.count(); j++ )
         slist.append( list[j].utf8() );
 
     const char **args = new (const char *)[slist.count() + 1];
     for ( j = 0; j < slist.count(); j++ )
         args[j] = slist.at(j);
     args[j] = NULL;
 
 #if !defined(QT_NO_COP)
     // an attempt to show a wait...
     // more logic should be used, but this will be fine for the moment...
     QCopEnvelope ( "QPE/System", "busy()" );
 #endif
 
 #ifdef HAVE_QUICKEXEC
     QString libexe = qpeDir()+"/binlib/lib"+args[0] + ".so";
     qDebug("libfile = %s", libexe.latin1() );
     if ( QFile::exists( libexe ) ) {
         qDebug("calling quickexec %s", libexe.latin1() );
         quickexecv( libexe.utf8().data(), (const char **)args );
     } else
 #endif
-            {    
-        if ( !::vfork() ) {
-            for ( int fd = 3; fd < 100; fd++ )
-                ::close( fd );
-            ::setpgid( ::getpid(), ::getppid() );
-            // Try bindir first, so that foo/bar works too
-            ::execv( qpeDir()+"/bin/"+args[0], (char * const *)args );
-            ::execvp( args[0], (char * const *)args );
-            _exit( -1 );
-        }
+    {           
+        bool success = false; 
+        int pfd [2];
+        if ( ::pipe ( pfd ) < 0 )
+            pfd [0] = pfd [1] = -1;
+    
+        pid_t pid = ::fork ( );
+        
+        if ( pid == 0 ) { // child
+            for ( int fd = 3; fd < 100; fd++ ) {
+                if ( fd != pfd [1] )
+                    ::close ( fd );
+            }
+            ::setpgid ( ::getpid ( ), ::getppid ( ));
+
+            // Closing of fd[1] indicates that the execvp succeeded!
+            if ( pfd [1] >= 0 )
+                ::fcntl ( pfd [1], F_SETFD, FD_CLOEXEC );
+             
+            // Try bindir first, so that foo/bar works too
+            ::execv ( qpeDir ( ) + "/bin/" + args [0], (char * const *) args );
+            ::execvp ( args [0], (char * const *) args );
+            
+            char resultByte = 1;
+            if ( pfd [1] >= 0 )
+                ::write ( pfd [1], &resultByte, 1 );
+            ::_exit ( -1 );                         
+        }
+        else if ( pid > 0 ) {
+            success = true;
+        
+            if ( pfd [1] >= 0 ) 
+                ::close ( pfd [1] );
+            if ( pfd [0] >= 0 ) {
+                while ( true ) {
+                    char resultByte;
+                    int n = ::read ( pfd [0], &resultByte, 1 );
+                    if ( n == 1 ) {
+                        success = false;
+                        break;
+                    }
+                    if (( n == -1 ) && (( errno == ECHILD ) || ( errno == EINTR )))
+                        continue;
+                        
+                    break; // success
+                }
+                ::close ( pfd [0] );
+            }
+        }
+        if ( success )    
+            StartingAppList::add( list[0] );
+        else
+            QMessageBox::warning( 0, "Error", "Could not start the application " + c, "Ok", 0, 0, 0, 1 );
     }
-    StartingAppList::add( list[0] );
 #endif //QT_NO_QWS_MULTIPROCESS
 }
 
 
 /*!
   Executes the application identfied by \a c, passing \a
   document if it isn't null.
 
   Note that a better approach might be to send a QCop message to the
   application's QPE/Application/\e{appname} channel.
 */
 void Global::execute( const QString &c, const QString& document )
 {
     if ( qApp->type() != QApplication::GuiServer ) {
         // ask the server to do the work
 #if !defined(QT_NO_COP)
         if ( document.isNull() ) {
             QCopEnvelope e( "QPE/System", "execute(QString)" );
             e << c;
         } else {
             QCopEnvelope e( "QPE/System", "execute(QString,QString)" );
             e << c << document;
         }
 #endif
         return;
     }
 
     // Attempt to execute the app using a builtin class for the app first
     // else try and find it in the bin directory
     if (builtin) {
         for (int i = 0; builtin[i].file; i++) {
             if ( builtin[i].file == c ) {
                 if ( running[i] ) {
                     if ( !document.isNull() && builtin[i].documentary )
                         setDocument(running[i], document);
                     running[i]->raise();
                     running[i]->show();
                     running[i]->setActiveWindow();
                 } else {
                     running[i] = builtin[i].func( builtin[i].maximized );
                 }
 #ifndef QT_NO_COP
                 QCopEnvelope e("QPE/System", "notBusy(QString)" );
                 e << c; // that was quick ;-)
 #endif
                 return;
             }
         }
     }
 
     //Global::invoke(c, document);
 
     // Convert the command line in to a list of arguments
     QStringList list = QStringList::split(QRegExp("  *"),c);
 
 #if !defined(QT_NO_COP)
     QString ap=list[0];
 
     qDebug("executing %s", ap.latin1() );
 
     /* if need be, sending a qcop message will result in an invoke, see
        preceeding function */
     invoke( ap );
     //{ QCopEnvelope env( ("QPE/Application/" + ap).latin1(), "raise()" ); }
     if ( !document.isEmpty() ) {
         QCopEnvelope env( ("QPE/Application/" + ap).latin1(), "setDocument(QString)" );
         env << document;
     }
 #endif
 }
 
 /*!
   Returns the string \a s with the characters '\', '"', and '$' quoted
   by a preceeding '\'.
 
   \sa stringQuote()
 */
 QString Global::shellQuote(const QString& s)
 {
     QString r="\"";
     for (int i=0; i<(int)s.length(); i++) {
         char c = s[i].latin1();
         switch (c) {
             case '\\': case '"': case '$':
                 r+="\\";
         }
         r += s[i];
     }
     r += "\"";
     return r;
 }
 
 /*!
   Returns the string \a s with the characters '\' and '"' quoted by a
   preceeding '\'.