Author: gonwan

Hacking QTerm

July 13, 2010 by gonwan·0 Comments

I read source code in QTerm and FQTerm today. Since I want to find reference for Ascii rendering control in my QAnsiEditor project. After hours of tracing and debugging, I was able to use the rendering control in simplest code. Here’s the patch in src/main.cpp:

# diff -ruN qterm-0.5.7/src/main.cpp qterm-0.5.7-1/src/main.cpp
--- qterm-0.5.7/src/main.cpp 2009-06-14 23:09:32.000000000 +0800
+++ qterm-0.5.7-1/src/main.cpp 2010-07-14 09:53:06.000000000 +0800
@@ -16,6 +16,9 @@
 #include "qtermconfig.h"
 #include "qtermglobal.h"
 #include "qterm.h"
+#include "qtermparam.h"
+#include "qtermwindow.h"
+#include "qtermscreen.h"
 
 #include <QtGlobal>
 #include <QApplication>
@@ -139,12 +142,27 @@
         return -1;
     }
 
-    QTerm::Frame * mw = new QTerm::Frame();
-    mw->setWindowTitle( "QTerm "+QString(QTERM_VERSION) );
-    mw->setWindowIcon( QPixmap(Global::instance()->pathLib()+"pic/qterm.png") );
-    mw->show();
-    a.connect( &a, SIGNAL(lastWindowClosed()), &a, SLOT(quit()) );
-    int res = a.exec();
+    //QTerm::Frame * mw = new QTerm::Frame();
+    //mw->setWindowTitle( "QTerm "+QString(QTERM_VERSION) );
+    //mw->setWindowIcon( QPixmap(Global::instance()->pathLib()+"pic/qterm.png") );
+    //mw->show();
+    //a.connect( &a, SIGNAL(lastWindowClosed()), &a, SLOT(quit()) );
+    //int res = a.exec();
+
+    using namespace QTerm;
+    Global::instance()->setScrollPosition(Global::Hide);
+    Param param;
+    param.m_BBSCode = "GBK";
+    param.m_nDispCode = 0;
+    param.m_strAddr = "bbs.yanxi.org";
+    //param.m_nProxyType = 4;
+    //param.m_strProxyHost = "gsopanel";
+    //param.m_uProxyPort = 8000;
+    Window *win = new QTerm::Window(0, param);
+    win->setAttribute(Qt::WA_DeleteOnClose);
+    win->setMinimumSize(600, 400);
+    win->show();
 
+    int res = a.exec();
     return res;
 }

# diff -ruN qterm-0.5.7/src/main.cpp qterm-0.5.7-1/src/main.cpp

--- qterm-0.5.7/src/main.cpp 2009-06-14 23:09:32.000000000 +0800

+++ qterm-0.5.7-1/src/main.cpp 2010-07-14 09:53:06.000000000 +0800

@@ -16,6 +16,9 @@

#include "qtermconfig.h"

#include "qtermglobal.h"

#include "qterm.h"

+#include "qtermparam.h"

+#include "qtermwindow.h"

+#include "qtermscreen.h"

#include <QtGlobal>

#include <QApplication>

@@ -139,12 +142,27 @@

return -1;

}

- QTerm::Frame * mw = new QTerm::Frame();

- mw->setWindowTitle( "QTerm "+QString(QTERM_VERSION) );

- mw->setWindowIcon( QPixmap(Global::instance()->pathLib()+"pic/qterm.png") );

- mw->show();

- a.connect( &a, SIGNAL(lastWindowClosed()), &a, SLOT(quit()) );

- int res = a.exec();

+ //QTerm::Frame * mw = new QTerm::Frame();

+ //mw->setWindowTitle( "QTerm "+QString(QTERM_VERSION) );

+ //mw->setWindowIcon( QPixmap(Global::instance()->pathLib()+"pic/qterm.png") );

+ //mw->show();

+ //a.connect( &a, SIGNAL(lastWindowClosed()), &a, SLOT(quit()) );

+ //int res = a.exec();

+ using namespace QTerm;

+ Global::instance()->setScrollPosition(Global::Hide);

+ Param param;

+ param.m_BBSCode = "GBK";

+ param.m_nDispCode = 0;

+ param.m_strAddr = "bbs.yanxi.org";

+ //param.m_nProxyType = 4;

+ //param.m_strProxyHost = "gsopanel";

+ //param.m_uProxyPort = 8000;

+ Window *win = new QTerm::Window(0, param);

+ win->setAttribute(Qt::WA_DeleteOnClose);

+ win->setMinimumSize(600, 400);

+ win->show();

+ int res = a.exec();

return res;

}

The screenshot of standalone mode:

The complete patch and patched source can be found here:

http://cid-481cbe104492a3af.office.live.com/browse.aspx/share/dev/QAnsiEditor

Using SVN in Ubuntu

July 9, 2010 by gonwan·0 Comments

Since I chose SVN as my VCS in google code, a SVN GUI client may be helpful. I found kdesvn. It’s free, powerful, and just there in the Ubuntu repository:

# sudo apt-get install kdesvn
# sudo apt-get install konqueror

1 2	# sudo apt-get install kdesvn # sudo apt-get install konqueror

The 2nd line is used to fix the bookmark issue in kdesvn :).

Then invoke the line below first:

# svn help

1	# svn help

This will create a default configuration directory for SVN in ~/.subversion/. In fact, any SVN command will do. There are configuration files located in /etc/subversion/. But they seems to be of no use.

Note, kdesvn will use SVN configuration files when perform operations. Now, we need to edit them.

1. Proxy

# gedit ~/.subversion/servers &

1	# gedit ~/.subversion/servers &

Uncomment and modify the following lines in [global] section:

http-proxy-host = <your_http_proxy_host>
http-proxy-port = <your_http_proxy_port>

1 2	http-proxy-host = <your_http_proxy_host> http-proxy-port = <your_http_proxy_port>

It seems that we can use separate settings for different host groups. This is not verified, leaves to you.

2. Password

SVN 1.6 added gnome/gnome-keyring and kde/kwallet credentials management support. Some additional options were introduced.

2.1 SVN 1.4.6 (Ubuntu 8.04, Hardy)

# gedit ~/.subversion/config &

1	# gedit ~/.subversion/config &

Uncomment and modify the following lines in [auth] section:

store-passwords = no
store-auth-creds = no

1 2	store-passwords = no store-auth-creds = no

You’re done. The 1st option prevents SVN from saving plain-text password locally. The 2nd even stops caching the credentials. Then every time you need an SVN authentication, a prompt appears.

Note: you cannot find an option in kdesvn’s configuration to set a user/password values. The application just use cached key values in ~/.subversion/auth/ directory.

2.2 SVN 1.6.6 (Ubuntu 10.04, Lucid)

If you do not want to save password, set the 2 values as that in Hardy. But they are deprecated and moved to ~/.subversion/servers.

# gedit ~/.subversion/servers &

1	# gedit ~/.subversion/servers &

Uncomment and modify the following lines in [global] section:

store-passwords = no
store-auth-creds = no

1 2	store-passwords = no store-auth-creds = no

Then the ~/.subversion/config file:

# gedit ~/.subversion/config &

1	# gedit ~/.subversion/config &

Uncomment and modify the following lines in [auth] section. Set to empty:

password-stores =

1	password-stores =

You’re done! All SVN behaviors are consistent with that in Hardy.

If you want to integrate with gnome-keyring or kwallet, modify the line to contain “gnome-keyring”, “kwallet” or both. Gnome-keyring does not integrate well with SVN, so I chose kwallet and have a test.

In kdesvn, go to Settings –> Configure Kdesvn –> Subversion, check the “Store passwords into KDE Kwallet” option. It’s the default configuration. Make sure that the option and the “password-stores” value are consistent. Otherwise, our kdesvn fail to commit code. When a kdesvn prompts to ask for username/password, check “Store password (into KDE Wallet)” option. Then you can view your saved login information in KWallet Manager application:

Some other screenshot of kdesvn in Lucid:

Main Window:

Revision Tree:

2 Projects on Google Code

July 8, 2010 by gonwan·0 Comments

1. QSkin: http://code.google.com/p/qskin/
QSkin is a framework for easier skinning Windows GUI applications. It uses hook technologies, so applications can apply a skin with almost no changes.
The initial ‘Q’ comes from my last name. 🙂

2. QAnsiEditor: http://code.google.com/p/qansieditor/
QAnsiEditor is a program to edit Ansi graphics. It aims to run on multiple platforms base on Qt library.

I will start to code the 2nd project first. Hope I can update it daily.
Release early, release often. =.=

Using Ubuntu Debug Packages in GDB (2)

July 7, 2010 by gonwan·0 Comments

From last blog, I’ve demostrated the usage of Ubuntu *-dbg packages. However, not all *-dbg packages seem to work as libssl0.9.8-dbg. For instance, libcurl3-dbg and libqt4-dbg packages do not work. I’m afraid some debug info are missing in these two packages. I’m not sure.

I googled a lot, but was not able to find a solution. So I decided to build the debug version of the two library myself. Here are steps for libcurl:

# sudo apt-get source libcurl3-dbg
# cd curl-7.19.7/
# ./configure --prefix=/usr/local --enable-debug --enable-static=0
# make

# sudo apt-get source libcurl3-dbg

# cd curl-7.19.7/

# ./configure --prefix=/usr/local --enable-debug --enable-static=0

# make

After all, the compiled binary is located in /home/gonwan/testgdb/curl-7.19.7/lib/.libs/. Note, this is a hidden folder.

Here comes our test code:

#include <curl/curl.h>
int main() {
    curl_easy_init();
    return 0;
}

#include <curl/curl.h>

int main() {

curl_easy_init();

return 0;

}

Build commands:

# gcc -g testcurl.c -o testcurl /usr/lib/libcurl.so.4

1	# gcc -g testcurl.c -o testcurl /usr/lib/libcurl.so.4

I use /usr/lib/libcurl.so.4 instead of lcurl, since lcurl will link the binary to /usr/lib/libcurl-gnutls.so.4. But I currently cannot afford it :(. Last, start our GDB:

# LD_LIBRARY_PATH=/home/gonwan/testgdb/curl-7.19.7/lib/.libs/ gdb ./testcurl
GNU gdb (GDB) 7.1-ubuntu
...
Reading symbols from /home/gonwan/testgdb/testcurl...done.
(gdb) b 3
Breakpoint 1 at 0x8048572: file testcurl.c, line 3.
(gdb) r
Starting program: /home/gonwan/testgdb/testcurl
[Thread debugging using libthread_db enabled]
Breakpoint 1, main () at testcurl.c:3
3           curl_easy_init();
(gdb) s
curl_easy_init () at easy.c:372
372         if(!initialized) {
(gdb) bt
#0  curl_easy_init () at easy.c:372
#1  0x08048577 in main () at testcurl.c:3
(gdb)

# LD_LIBRARY_PATH=/home/gonwan/testgdb/curl-7.19.7/lib/.libs/ gdb ./testcurl

GNU gdb (GDB) 7.1-ubuntu

...

Reading symbols from /home/gonwan/testgdb/testcurl...done.

(gdb) b 3

Breakpoint 1 at 0x8048572: file testcurl.c, line 3.

(gdb) r

Starting program: /home/gonwan/testgdb/testcurl

[Thread debugging using libthread_db enabled]

Breakpoint 1, main () at testcurl.c:3

3 curl_easy_init();

(gdb) s

curl_easy_init () at easy.c:372

372 if(!initialized) {

(gdb) bt

#0 curl_easy_init () at easy.c:372

#1 0x08048577 in main () at testcurl.c:3

(gdb)

It prints the backtrace now, though I’m not so accustomed to console debugging. I add the LD_LIBRARY_PATH environment to let our test program find our homemade version of libcurl.so.4. In fact, we can run ldd like following lines. You see the re-direction?

# ldd ./testcurl | grep libcurl
    libcurl.so.4 => /usr/lib/libcurl.so.4 (0x00943000)
# LD_LIBRARY_PATH=/home/gonwan/testgdb/curl-7.19.7/lib/.libs/ ldd ./testcurl | grep libcurl
    libcurl.so.4 => /home/gonwan/testgdb/curl-7.19.7/lib/.libs/libcurl.so.4 (0x00318000)

# ldd ./testcurl | grep libcurl

libcurl.so.4 => /usr/lib/libcurl.so.4 (0x00943000)

# LD_LIBRARY_PATH=/home/gonwan/testgdb/curl-7.19.7/lib/.libs/ ldd ./testcurl | grep libcurl

libcurl.so.4 => /home/gonwan/testgdb/curl-7.19.7/lib/.libs/libcurl.so.4 (0x00318000)

Later, I successfully made it possible to debug Qt source code in IDE. I chose QtCreator, since it has both windows and linux version, and it’s easy to install and configure. I also built my homemade version of Qt:

# sudo apt-get source libqt4-dbg
# cd qt4-x11-4.6.2/
# ./configure -prefix /usr/local -debug-and-release -no-qt3support -no-webkit -no-script -no-scripttools -no-xmlpatterns -no-phonon -no-multimedia -no-declarative -make libs -nomake tools -nomake examples -nomake demos -nomake docs -nomake translations -fast
# make

# sudo apt-get source libqt4-dbg

# cd qt4-x11-4.6.2/

# ./configure -prefix /usr/local -debug-and-release -no-qt3support -no-webkit -no-script -no-scripttools -no-xmlpatterns -no-phonon -no-multimedia -no-declarative -make libs -nomake tools -nomake examples -nomake demos -nomake docs -nomake translations -fast

# make

I only built the most common modules, excluding webkit, script, xmlpatterns, phonon, multimedia and declarative modules. It took only 25 minutes to finish (An entire build under windows may take 3 – 4 hours.). After all, start your QtCreator, create a Qt console project with the source below:

#include <QtCore/QString>
int main() {
    QString s = "1234567";
    int i = s.indexOf('3');
    return i != 2;
}

#include <QtCore/QString>

int main() {

QString s = "1234567";

int i = s.indexOf('3');

return i != 2;

}

Build the project in debug mode. And now, here’s the magic: Go to Project tab –> Run Settings –> Run Environment, append our homemade Qt library path to LD_LIBRARY_PATH. In my example, it’s /home/gonwan/testgdb/qt4-x11-4.6.2/lib. Ok, you’re almost done! Go back to the Edit tab, set a breakpoint at line 4 (or line 3 as you like), press F5 to start debugging the project. Then continue pressing F11, you will find GDB has stepped into Qt source code! Let me take a screenshot:

In order to load our homemade *.so, we can also run “make install”.

Using Ubuntu Debug Packages in GDB

July 7, 2010 by gonwan·0 Comments

I will use openssl library as example. Here’s a simplest source:

#include <openssl/ssl.h>
int main() {
    SSL_library_init();
    return 0;
}

#include <openssl/ssl.h>

int main() {

SSL_library_init();

return 0;

}

Now build and start your GDB, note the ‘-g’ option is necessary:

# gcc -g testopenssl.c -o testopenssl -lssl
# gdb ./testopenssl
GNU gdb 6.8-debian
...
(gdb) b 3
Breakpoint 1 at 0x8048495: file testopenssl.c, line 3.
(gdb) r
Starting program: /home/binson/testgdb/testopenssl
Breakpoint 1, main () at testopenssl.c:3
3       SSL_library_init();
(gdb) s
4       return 0;
(gdb)

# gcc -g testopenssl.c -o testopenssl -lssl

# gdb ./testopenssl

GNU gdb 6.8-debian

...

(gdb) b 3

Breakpoint 1 at 0x8048495: file testopenssl.c, line 3.

(gdb) r

Starting program: /home/binson/testgdb/testopenssl

Breakpoint 1, main () at testopenssl.c:3

3 SSL_library_init();

(gdb) s

4 return 0;

(gdb)

GDB cannot step into openssl source code, since there’s no debug symbol found. In Ubuntu, we can install it using apt-get. I’m using Hardy(8.04):

# sudo apt-get install libssl0.9.8-dbg

1	# sudo apt-get install libssl0.9.8-dbg

Launch our GDB again:

# gdb ./testopenssl
GNU gdb 6.8-debian
...
(gdb) b 3
Breakpoint 1 at 0x8048495: file testopenssl.c, line 3.
(gdb) r
Starting program: /home/binson/testgdb/testopenssl
Breakpoint 1, main () at testopenssl.c:3
3       SSL_library_init();
(gdb) s
SSL_library_init () at ssl_algs.c:68
68  ssl_algs.c: No such file or directory.
    in ssl_algs.c
(gdb)

# gdb ./testopenssl

GNU gdb 6.8-debian

...

(gdb) b 3

Breakpoint 1 at 0x8048495: file testopenssl.c, line 3.

(gdb) r

Starting program: /home/binson/testgdb/testopenssl

Breakpoint 1, main () at testopenssl.c:3

3 SSL_library_init();

(gdb) s

SSL_library_init () at ssl_algs.c:68

68 ssl_algs.c: No such file or directory.

in ssl_algs.c

(gdb)

Symbols are found, GDB prompt for missing source files! We can install by typing:

# sudo apt-get source libssl0.9.8

1	# sudo apt-get source libssl0.9.8

The source files will be downloaded and extracted in openssl-0.9.8g folder. Now we wanna attach the source files when debugging.

# gdb ./testopenssl
GNU gdb 6.8-debian
...
(gdb) dir openssl-0.9.8g/ssl/
Source directories searched: /home/binson/testgdb/openssl-0.9.8g/ssl:$cdir:$cwd
(gdb) b 3
Breakpoint 1 at 0x8048495: file testopenssl.c, line 3.
(gdb) r
Starting program: /home/binson/testgdb/testopenssl
Breakpoint 1, main () at testopenssl.c:3
3       SSL_library_init();
(gdb) s
SSL_library_init () at ssl_algs.c:68
68      EVP_add_cipher(EVP_des_cbc());
(gdb) bt
#0  SSL_library_init () at ssl_algs.c:68
#1  0x0804849a in main () at testopenssl.c:3
(gdb)

# gdb ./testopenssl

GNU gdb 6.8-debian

...

(gdb) dir openssl-0.9.8g/ssl/

Source directories searched: /home/binson/testgdb/openssl-0.9.8g/ssl:$cdir:$cwd

(gdb) b 3

Breakpoint 1 at 0x8048495: file testopenssl.c, line 3.

(gdb) r

Starting program: /home/binson/testgdb/testopenssl

Breakpoint 1, main () at testopenssl.c:3

3 SSL_library_init();

(gdb) s

SSL_library_init () at ssl_algs.c:68

68 EVP_add_cipher(EVP_des_cbc());

(gdb) bt

#0 SSL_library_init () at ssl_algs.c:68

#1 0x0804849a in main () at testopenssl.c:3

(gdb)

Oh! Everything works!

0x2B|~0x2B

My broken wings still strong enough to cross the ocean with.

Author: gonwan

Hacking QTerm

Using SVN in Ubuntu

1. Proxy

2. Password

2.1 SVN 1.4.6 (Ubuntu 8.04, Hardy)

2.2 SVN 1.6.6 (Ubuntu 10.04, Lucid)

2 Projects on Google Code

Using Ubuntu Debug Packages in GDB (2)

Using Ubuntu Debug Packages in GDB