View source for Running Qt C++ Programs on the XGrid

--[[User:Thiebaut|D. Thiebaut]] 16:12, 3 June 2010 (UTC)
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This short How-To page shows how to deploy a Qt3 C++ application on the XGrid.  The problem addressed is that the Qt libraries might not be installed on the XGrid client, which will make the application fail when it starts running on a client. 
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=The Problem=

* We have an executable generated by compiling a C++ program using the Qt 3.6 libraries.
* Want to run the Qt executable on the XGrid.
* Qt 3.6 is not installed on the XGrid clients
* Qt was installed assuming its libraries would be loaded dynamically.
* We don't want to reinstall or reconfigure Qt.

=The solution=

* Use '''otool''' to find all the libraries that are non system libraries (we assume they are all in /opt/local/lib) and assume that they will not be on the XGrid clients.
* Copy all these libraries next to the executable, and modify the executable with '''install_name_tool''' such that the path of the libraries as it wants to refer to them is not absolute, but becomes whatever the executable path is.

:For example, if the executable contains a reference to '''/opt/local/lib/libqt-mt.3.dylib''', it should be changed to  '''@executable_path/libqt-mt.3.dylib'''.

* This process is repeated for all the libraries brought in, so that if they too rely on non-system libraries, they will be modified to have a new path to them, and these libraries will be brought in in turn.

* To do this efficiently, we use a Python utility called [[makeStaticPackage.py]].

* [[makeStaticPackage.py]] must be started in an empty directory and copies into it the original executable, as well as all the non-system libraries, one after the other.  It then generates a text file that can be used by another Python script, [[CSC352 makeBatchMulti.py| makeBatchMulti.py]], for creating an XGrid batch file.

=Example: creating a Qt3 application and deploying it on the XGrid=

==Source Code==

===main.cpp===
<br />
<source lang="cpp">
#include "engine.h"

using namespace std;

int main(int argc, char *argv[]) {

  if ( argc<2 ) {
    cerr << "Syntax: " << argv[0] << " parameter"  << endl << endl;
    return 1;
  }

  engineClass engine;
  engine.go();
}


</source>
<br />

===engine.h===
<br />
<source lang="cpp">
#ifndef ENGINE_H
#define ENGINE_H
// engine.h
// D. Thiebaut
// 
#include <iostream>
#include <qobject.h>

using namespace std;


//---------------------------------------------------------------------------------
//---------------------------------------------------------------------------------
class engineClass: public QObject {
  Q_OBJECT
    private:
       bool                 debug;
       QString              inFileName;
       QString              outFileName;

    public:
       engineClass() { 
	 debug = false;
       }
       void hello();

    public slots:
       void go();

};

#endif

</source>
<br />

===engine.cpp===
<br />
<source lang="cpp">
#include "engine.h"
#include <iostream>

void engineClass::go() {
  cout << "hello there!\n\n";
}

void engineClass::hello() {
  cout << "hello world!\n\n";
}

</source>
<br />
===filterwiki10.pro===
<code><pre>

LIBS += -L/opt/local/include/qt3/
INCLUDEPATH += /opt/local/include/qt3/

 TARGET = ./filterwiki10
CONFIG += release \
          warn_on  \
          thread 

TEMPLATE = app 
CONFIG -= moc
INCLUDEPATH += .

# Input
SOURCES += main.cpp \
          engine.cpp 

HEADERS += engine.h 

</pre></code>

==Compiling==

* Simply go through the process of compiling Qt3 C++ applications:

 % cd ''workingDirectory''
 % ls
 main.cpp  engine.h  engine.cpp  Makefile filterwiki.pro
   
 % export QTDIR=/opt/local
 % rm Makefile
 % qmake -makefile
 % qmake
 % gmake

 g++-4.0 -c -pipe -Wall -W -Os  -D__DARWIN_X11__ -DQT_NO_DEBUG -I/opt/local/lib/qt3/mkspecs/default -I. \
       -I/opt/local/include/qt3 -I/opt/local/lib/qt3/include -I/opt/local/include -o main.o main.cpp
 g++-4.0 -c -pipe -Wall -W -Os  -D__DARWIN_X11__ -DQT_NO_DEBUG -I/opt/local/lib/qt3/mkspecs/default -I. \
       -I/opt/local/include/qt3 -I/opt/local/lib/qt3/include -I/opt/local/include -o engine.o engine.cpp
 g++-4.0 -c -pipe -Wall -W -Os  -D__DARWIN_X11__ -DQT_NO_DEBUG -I/opt/local/lib/qt3/mkspecs/default -I. \
       -I/opt/local/include/qt3 -I/opt/local/lib/qt3/include -I/opt/local/include -o moc_engine.o moc_engine.cpp
 test -d ../../../bin/ || mkdir -p ../../../bin/
 g++-4.0 -Wl,-dylib_file,/System/Library/Frameworks/OpenGL.framework/Versions/A/Libraries/libGL.dylib: \
       /System/Library/Frameworks/OpenGL.framework/Versions/A/Libraries/libGL.dylib -prebind \
       -o ../../../bin/filterwiki9 main.o engine.o moc_engine.o   -L/opt/local/lib -L/opt/local/lib -L/opt/local/lib \ 
       -L/opt/local/include/qt3/ -lqt-mt -lXext -lX11 -lm

==Creating the "static package"==

 % cp ~/bin/filterwiki9 .
 % mkdir XGridVersion
 % cd XGridVersion
 % makeStaticPackage.py ../filterwiki9

 ----------------------- SUMMARY ----------------------  
 Copied and processed /opt/local/lib/libfreetype.6.dylib
 Copied and processed /opt/local/lib/libqt-mt.3.dylib
 Copied and processed /opt/local/lib/libICE.6.dylib
 Copied and processed /opt/local/lib/libcrypto.0.9.8.dylib
 Copied and processed /opt/local/lib/libXmu.6.dylib
 Copied and processed /opt/local/lib/libXfixes.3.dylib
 Copied and processed /opt/local/lib/libXcursor.1.dylib
 Copied and processed /opt/local/lib/libSM.6.dylib
 Copied and processed /opt/local/lib/libGL.1.dylib
 Copied and processed /opt/local/lib/libXext.6.dylib
 Copied and processed /opt/local/lib/libXt.6.dylib
 Copied and processed /opt/local/lib/libXdmcp.6.dylib
 Copied and processed /opt/local/lib/libfontconfig.1.dylib
 Copied and processed /opt/local/lib/libz.1.dylib
 Copied and processed /opt/local/lib/libX11.6.dylib
 Copied and processed /opt/local/lib/libXinerama.1.dylib
 Copied and processed /opt/local/lib/libXau.6.dylib
 Copied and processed /opt/local/lib/libexpat.1.dylib
 Copied and processed /opt/local/lib/libssl.0.9.8.dylib
 Copied and processed /opt/local/lib/libXrender.1.dylib
 Copied and processed ../filterwiki9
 Copied and processed /opt/local/lib/libXrandr.2.dylib
 Copied and processed /opt/local/lib/mysql5/mysql/libmysqlclient.16.dylib
 Copied and processed /opt/local/lib/libXft.2.dylib
 Copied and processed /opt/local/lib/libiconv.2.dylib
 ------------------------------------------------------
 
 
 To create batch file, type
 makeBatchMulti.py filterwiki9.batch < filterwiki9.in
  
==Creating the XGrid Batch file==

* Simply execute the command listed by the previous execution of '''makeStaticPackage.py'''

 % makeBatchMulti.py filterwiki9.batch < filterwiki9.in
 
 
 XGrid batch file maker 
 Creates a batch file for the XGrid system from a collection of 
 data files and programs
 
 
 Please enter your name to identify the batch job: 
 Please enter the names of the different programs needed by the batch job.
 Enter them one per line.  Press Enter twice when done.
 Program #1 > Program #2 > Program #3 > Program #4 > Program #5 > Program #6 > Program #7 > 
 Program #8 >  Program #9 > Program #10 > Program #11 > Program #12 > Program #13 > Program #14 > 
 Program #15 > Program #16  > Program #17 > Program #18 > Program #19 > Program #20 > Program #21 > 
 Program #22 > Program #23 > Program #24 > Program #25 > Program #26 > 
 Please enter the names of the different data files needed. 
 No need to list the name of temporary files created by the programs.
 Enter them one per line.  Press Enter twice when done.
 Data file #1 > 
 Enter the commands that the XGrid should run.  Enter each command on one line.
 For each line, enter the name of the program followed by all the arguments. 
 Do not use redirection or pipes in the command lines.
 Enter an empty line to stop.
 Command #1 > Command #2 > [xgridmac]
 
 
 % ls -ltr

 total 89144
 -rwxr-xr-x  1 thiebaut  staff   6334116 Jun  3 11:55 libqt-mt.3.dylib*
 -rwxr-xr-x  1 thiebaut  staff     65372 Jun  3 11:55 libXext.6.dylib*
 -rwxr-xr-x  1 thiebaut  staff     23012 Jun  3 11:55 libXdmcp.6.dylib*
 -rwxr-xr-x  1 thiebaut  staff     13784 Jun  3 11:55 libXau.6.dylib*
 -rwxr-xr-x  1 thiebaut  staff   1204428 Jun  3 11:55 libX11.6.dylib*
 -rwxr-xr-x  1 thiebaut  staff     91468 Jun  3 11:55 filterwiki9*
 -rwxr-xr-x  1 thiebaut  staff     83040 Jun  3 11:55 libz.1.dylib*
 -rwxr-xr-x  1 thiebaut  staff    320932 Jun  3 11:55 libssl.0.9.8.dylib*
 -rwxr-xr-x  1 thiebaut  staff   1404052 Jun  3 11:55 libmysqlclient.16.dylib*
 -rw-r--r--  1 thiebaut  staff   1065668 Jun  3 11:55 libiconv.2.dylib
 -rwxr-xr-x  1 thiebaut  staff    548736 Jun  3 11:55 libfreetype.6.dylib*
 -rwxr-xr-x  1 thiebaut  staff    201836 Jun  3 11:55 libfontconfig.1.dylib*
 -rwxr-xr-x  1 thiebaut  staff    146384 Jun  3 11:55 libexpat.1.dylib*
 -rwxr-xr-x  1 thiebaut  staff   1435388 Jun  3 11:55 libcrypto.0.9.8.dylib*
 -rwxr-xr-x  1 thiebaut  staff    343540 Jun  3 11:55 libXt.6.dylib*
 -rwxr-xr-x  1 thiebaut  staff     40988 Jun  3 11:55 libXrender.1.dylib*
 -rwxr-xr-x  1 thiebaut  staff     36720 Jun  3 11:55 libXrandr.2.dylib*
 -rwxr-xr-x  1 thiebaut  staff     90916 Jun  3 11:55 libXmu.6.dylib*
 -rwxr-xr-x  1 thiebaut  staff     13588 Jun  3 11:55 libXinerama.1.dylib*
 -rwxr-xr-x  1 thiebaut  staff     76988 Jun  3 11:55 libXft.2.dylib*
 -rwxr-xr-x  1 thiebaut  staff     23276 Jun  3 11:55 libXfixes.3.dylib*
 -rwxr-xr-x  1 thiebaut  staff     39184 Jun  3 11:55 libXcursor.1.dylib*
 -rwxr-xr-x  1 thiebaut  staff     37056 Jun  3 11:55 libSM.6.dylib*
 -rwxr-xr-x  1 thiebaut  staff     91216 Jun  3 11:55 libICE.6.dylib*
 -rwxr-xr-x  1 thiebaut  staff    292212 Jun  3 11:55 libGL.1.dylib*
 -rw-r--r--  1 thiebaut  staff       449 Jun  3 11:55 filterwiki9.in
 -rw-r--r--  1 thiebaut  staff  '''31555722''' Jun  3 11:58 filterwiki9.batch 

* This create quite a large file to distribute: 31 MB.  But a static version of the Qt executable would have been quite large as well...

==Running the Qt3 Application on the XGrid==

* Simply submit the batch file created to the XGrid 
** Here we simply verify that the program gets loaded and checks the command line arguments, which are missing.  It prints the syntax information back--good enough a test for us!
** We rely on another Python script, [[CSC352 getXGridOutput.py| getXGridOutput.py]], to interact with the XGrid, get the Pids and collect the outputs.


 '''% time xgrid -job batch filterwiki9.batch | getXGridOutput.py''' 
 
 Syntax: /var/xgrid/agent/tasks/jhv4aScs/working/filterwiki9 rawXmlWikiFileName -d dir [-1] [--onefile]
 
 will take a raw wikipedia xml file and filter out the titles, ids,
 categories, and concepts, and store them in a file with the same
 name, but with a .filtered.xml extension
 -d dir: the absolute path of the directory where to store the xml files
 -D: put in debug mode
 [-N nnnn]: max number of pages to process
 [--onefile]: store the xml into one large file instead of several small ones
 [-1] indicates that 1-word concepts should be kept
 
 
 Total execution time: 0.000000 seconds
 
 
 
 
 real	0m5.275s
 user	0m1.261s
 sys	0m0.715s

* Note that even though the program didn't really execute, and displayed its syntax information, the loading of the 32 MB batch file and execution on the XGrid main node took 5.2 seconds of real time.

<br />
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[[Category:XGrid]][[Category:Tutorials]][[Category:C++]][[Category:Qt3]]