I am trying to write a GDB frontend. I use GDB for debugging embedded targets, especially with ARM processors. I have used Eclipse before, but I didn't like it very much. At work, we use Lauterbach Trace32, which is one of the most comfortable debuggers I have ever used. That's why I started a project where I try to implement a very similar application as a GDB frontend, which is specialised to embedded debugging.
However, I already have implemented some very basic commands, like viewing the source code, viewing registers of the target etc., which works well. Currently, I am implementing breakpoints. But for this I need some help.
I use Qt (with Qtcreator) on Linux for my project, so I have set up a QProcess for the gdb running in the background. I use the GDB Mi2 interface to communicate with gdb. Then, using write() I can send commands and with a SIGNAL, I can receive the responses from GDB. This works well, but the answers from GDB in this MI format are very ugly to parse. Could anyone give me a hint how this can be done in a elegant way? I tried BOOST to build a parser, which worked, but this is a much too complicated way in my opinion. Is there some better way to parse the GDB responses?
There's no truly great way to parse MI. MI is quite old and so predates the widespread adoption of XML and JSON. Also, even more unfortunately for you, there are a few known MI emission bugs in gdb (search bugzilla and the list archives) -- spots where gdb's MI output doesn't conform to the MI grammar. These have gone unfixed because it was judged that changing the output (without bumping the MI version number, something nobody seems to want to drive) would break existing parsers without much corresponding benefit.
The good news is that there are a few reusable parsers already in existence. So I would suggest using one of those. The parser in nemiver is written in C++ and is a reusable library. However as you're already using Qt you might check out the parsers in Qt Creator or KDevelop.
It might also be possible to roll your own gdb interface by programming gdb in Python. However, there are likely to be some holes in gdb's Python API, so I would only recommend it if you also want to get into hacking on the gdb Python layer as well.
There is the pygdbmi python library for exactly this purpose (it did not exist when you originally asked your question) https://github.com/cs01/pygdbmi
gdbgui is a frontend that utilizes pygdbmi: https://github.com/cs01/gdbgui
Have fun!
Disclaimer: I am the developer.
Qt Creator itself has a parser for (some superset of) the MI protocol, see plugins/debugger/debuggerprotocol.{h,cpp} in its sources. This (superset) protocol also used to capture data from Qt Creator's "pretty printing" produces and also serves as the debugger->frontend channel for the LLDB integration.
The protocol implementation is fairly well separated from the rest of Qt Creator's debugger plugin. It should be re-usable.
Related
I want to make an app using Qt that communicates with serial port.
The problem is that I cant find a library that works and does this thing.
I need a non General Public License library I think.
Actually I am not sure cause I don't know if I can use a General Public License library for a closed source program.
I found qextserialport but I am unable to build it using Qt 4.7.3. I added all the needed headers but it fails on some functions.
Can anyone help me here?
If you want to go closed source and distribute your application, you can't use GPL. You can use LGPL when linking either dynamically or statically. For the latter, you need to provide object files for all of your code, so that they can be statically re-linked with Qt.
Conercerning your base issue, Qt 5 includes a serial port module. On Qt 4, you'll need a platform-specific solution. Reducing the scope might help to point you to something. I suggest that if you don't target portability, you should add relevant tags and comments. Otherwise, saying that you need a portable solution is a good thing too.
As far as I know, on most paltforms, accessing to serial port requires higher privileges, so be ready for that in your deployment.
Concerning qtextserialport, license is BSD so it would work for your clsoed source application. If you post a compilation issue on where it fails, maybe people will be able to help you
I tried to compile it using VC2010 and Qt 4.7.2 and head of project (I just cloned it) compiles flawlessly: I got a nice qextserialport1.dll (that I admit I didn't try using).
There is a QtSerialPort add-on nowadays that can be used for such tasks. I am one of the maintainers behind it. That is the "official" Qt add-on nowadays, so I would suggest switching to it. It will also support Qt 4.
It is properly useful for commercial code (closed source) as I have also been doing that. If we do not yet have an exception for static linking, I would even accept that if legally possible.
My opinion about licenses is somewhere in-between LGPLv2 and MIT, i.e. LGPLv2 + static linking.
Here you can find my blog post about it. It also works fine with Qt 4 as we have had put some effort into that support, too.
http://lpapp.blogspot.co.uk/2013/02/qtserialport-in-qt-51.html
Put shortly: For those familiar with language bindings in Qt and Gtk+. E.g. python and ruby. Are there any quality or capability difference?
More background: I know C++ and Qt very well. Minimal experience with Gtk+. I know C++ is not ideal for language bindings due to the lack of a well defined ABI (application binary interface). I also read that Gtk+ was designed to be bound to other languages. So I wonder how this manifets itself in practice. Are the Gtk+ bindings better maintained or work better in some way than their Qt counterparts?
I am presently quite interested in the Go language, and they have started developing Gtk+ bindings. However C++ bindings is far away. It makes me wonder whether learning Gtk+ is worth it.
I've used GTK and Qt in C++ and also PyGTK and PyQt in Python quite extensively.
Qt beats GTK hands down - its a much more flexible, modern and clean API. GTK is also lacking some features that are important to me. From a framework point of view, I'd recommend Qt.
As for langauge bindings (I can only speak about Python, since I've never used the Ruby equivalents), I think PyGTK (using Glade and a wrapper like Padraig Bradys libglade) make GUI programming insanely easy and fun. However, if you can GPL your software (or pay the license fee), then PyQt is also a good option, and while not quite as friendly as PyGTK + Glade (in that with GTK you can define your UI in Glade as a separate XML file, so you can tweak the UI without touching code; in Qt if you want to use QtDesigner, you have to generate code using uic, if I remember correctly) the API itself is really really nice to use and mirrors the Qt frameworks clean design very closely.
Over all, I'd probably recommend using PyQt over PyGTK, but I may be biased since I much prefer Qt over GTK nowadays, though you could try both out and see which you prefer - they are both almost trivial to get working.
If you are looking for a great book on PyQt, I'd recomment Rapid GUI Programming qith Python and Qt.
To summarize: IMHO Qt beats GTK in both quality and capability. Both PyGTK and PyQt are of excellent quality and capability mirrors the underlying framework, though PyGTK can load Glade xml files.
I think that GTK bindings are older than Qt ones (and so a bit more mature) but they are both usable and your previous knowledge of Qt should be the main factor in your choice.
I developed small GUIs using both Qt and GTK with their python bindings and found the two equivalent. Some regrets though on the PyQt bindings with Qt container (QVector, ...) that are not translated into regular python data structure and thus add a bit of complexity to the code. I didn't recall the same issues using PyGTK.
I have worked with both PyQt and PyGTK and I would say they're both regularly mantained and synched with their parent frameworks. However, and this is completely subjective, I found more rewarding working with PyGTK than with PyQt, even if I hadn't previously written any code using GTK. If you know well Qt, go with Qt though.
I have been trying a few combinations around Qt : RubyQt, JRuby + Jambi, PyQt. The first one quickly ends up in various segmentation-faults. My Qt skills may be the problem but all in all the seg faults are not quite readable. The forum for RubyQt is nearly dead so don't expect to find much information there.
So I moved to JRuby + Jambi. This worked until well, I reached some missing functions here and there. Plus I had to implement a proper signal/connect for JRuby. So, more or less a hack. Not convincing.
Finally I moved to Python (wich I don't like very much). But woooh, what a difference. Bindings are up to date, I have still to ecnounter a segmetatio fault, error messages are most of the time very explanatory. So as far as I'm concerned Python+Qt is a clear winner.
Please note that I was trying these combinations in order to find a proper language/qt binding so that I can create a production ready with my commutation hours (roughly 2 hours a day). So my tolerance to small-but-annoying problems such as segmentation faults is 0. I also have to develop on Windows and Linux. So Windows installation is necessary (and once again, Python is a clear winner here).
there are C++ gtk+ bindings. Google for gtkmm.
Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
Questions asking us to recommend or find a tool, library or favorite off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it.
Closed 9 years ago.
Improve this question
A few years ago I looked into using some build system that isnt Make, and tools like CMake and SCons seemed pretty primitive. I'd like to find out if the situation has improved. So, under the following criteria, what is currently the best build tool:
platform agnostic: should work on windows, linux, mac
language agnostic: should have built-in support for common things like building C/C++ and other static langs. I guess it doesn't need to support the full autotools suite.
extensible: I need to be able to write rules to generate files, like from restructuredText, latex, custom formats, etc. I dont really care what language I have to write the rules in, but I would prefer a real language rather than a DSL.
I would prefer to avoid writing any XML by hand, which I think for example ant requires.
Freely available (preferably open source)
The term "best" is slightly subjective, but I think answers can be rated objectively by the criteria above.
I'd definitively put my vote up for premake. Although it is not as powerful as it's older brothers, it's main advantage is absurd simplicity and ease of use. Makes writing multi-compiler, multi-platform code a breeze, and natively generates Visual Studio solutions, XCode projects, Makefiles, and others, without any additional work needed.
So, judging purely by the criteria set forth in the question, the build system that seems like the best fit is probably waf - pure Python, provides support for C++ and other languages, general, powerful, not a DSL.
However, from my personal experience, I prefer CMake for C++ projects. (I tried CMake, SCons, and waf, and liked them in roughly that order). CMake is a general solution, but it has built-in support for C++ that makes it nicer than a more generic solution when you're actually doing C++.
CMake's build model for C++ is more declarative and less imperative, and thus, to me, easier to use. The CMake language syntax isn't great, but a declarative build with odd syntax beats an imperative build in Python. Of the three, CMake also seems to have the best support for "advanced" things like precompiled headers. Setting up precompiled headers reduced my rebuild time by about 70%.
Other pluses for CMake include decent documentation and a sizable community. Many open source libraries have CMake build files either in-tree or provided by the CMake community. There are major projects that already use CMake (OGRE comes to mind), and other major projects, like Boost and LLVM, are in the process of moving to CMake.
Part of the issue I found when experimenting with build systems is that I was trying to build a NPAPI plugin on OS X, and it turns out that very few build systems are set up to give XCode the exact combination of flags required to do so. CMake, recognizing that XCode is a complex and moving target, provides a hook for manually setting commands in generated XCode projects (and Visual Studio, I think). This is Very Smart as far as I'm concerned.
Whether you're building a library or an application may also determine which build system is best. Boost still uses a jam-based system, in part because it provides the most comprehensive support for managing build types that are more complex than "Debug" and "Release." Most boost libraries have five or six different versions, especially on Windows, anticipating people needing compatible libraries that link against different versions of the CRT.
I didn't have any problems with CMake on Windows, but of course your mileage may vary. There's a decent GUI for setting up build dependencies, though it's clunky to use for rebuilds. Luckily there's also a command-line client. What I've settled on so far is to have a thin wrapper Makefile that invokes CMake from an objdir; CMake then generates Makefiles in the objdir, and the original Makefile uses them to do the build. This ensures that people don't accidentally invoke CMake from the source directory and clutter up their repository. Combined with MinGW, this "CMake sandwich" provides a remarkably consistent cross-platform build experience!
Of course that depends on what your priorities are. If you are looking primarily for ease of use, there are at least two new build systems that hook into the filesystem to automatically track dependencies in a language agnostic fashion.
One is tup:
http://gittup.org/tup/
and the other is fabricate:
http://code.google.com/p/fabricate/
The one that seems to be the best performing, portable, and mature (and the one I have actually used) is tup. The guy who wrote it even maintains a toy linux distro where everything is a git submodule, and everything (including the kernel) is build with tup. From what I've read about the kernel's build system, this is quite an accomplishment.
Also, Tup cleans up old targets and other cruft, and can automatically maintain your .gitignore files. The result is that it becomes trivial to experiment with the layout and names of your targets, and you can confidently jump between git revisions without rebuilding everything. It's written in C.
If you know haskell and are looking for something for very advanced use cases, check out shake:
http://community.haskell.org/~ndm/shake/
Update: I haven't tried it, but this new "buildsome" tool also hooks into the filesystem, and was inspired by tup, so is relevant:
https://github.com/ElastiLotem/buildsome
CMake
CMake is an extensible, open-source
system that manages the build process
in an operating system and in a
compiler-independent manner.
Gradle seems to match all the criteria mentioned above.
It's a build system which took the best of Maven and Ant combined. To me, that's the best.
The Selenium project is moving over to Rake, not because its the best but because it handles multiple languages slightly better than all the other build tools and is cross platform (developed in Ruby).
All build tools have their issues and people learn to live with them. Something that runs on the JVM tends to be really good for building apps so Ant, Maven (i know its hideous), Ivy, Rake
Final Builder is well known in Windows world
smooth build matches most of your requirements.
platform agnostic: yes, it's written in java
language agnostic: it doesn't support c/c++t yet, only java but it is extensible via plugins written in java so adding more compilers support is not a problem
extensible: yes, you can implement smooth function via java plugin, you can also create smooth function via defining it as expression built of other smooth functions.
I would prefer to avoid writing any XML: you won't see a single line of it in smooth build
Freely available: yes, Apache 2 license
disclosure: I'm the author of smooth build.
The article Porting Qt for Embedded Linux to Another Operating System lists five things you have to do to port Qt for Embedded Linux to another OS. From the article:
There are several issues to be aware of if you plan to do your own port to another operating system. In particular you must resolve Qt for Embedded Linux's shared memory and semaphores (used to share window regions), and you must provide something similar to Unix-domain sockets for inter-application communication. You must also provide a screen driver, and if you want to implement sound you must provide your own sound server. Finally you must modify the event dispatcher used by Qt for Embedded Linux.
Is it really this easy to port Qt to another OS, or have i missed some information?
Another important component to port would be QAtomic, to ensure that you can have atomic operations and implicit sharing working well. See also
http://labs.trolltech.com/blogs/2007/08/28/say-hello-to-qatomicint-and-qatomicpointer/
Since Qt has been ported a large number of times it seems logical that it would be inherently simple. However the issue really is on the platform you are porting to and how many features it currently supports.
Assuming you find all those things easy, then the port is easy.
After investigating this in more detail I have come to the conclusion that the article "Porting Qt for Embedded Linux to Another Operating System" assumes that you are porting Qt to a very "linux-like" OS.
I have attempted this and currently making progress.
Some difficulties:
IDE - I have to manually add all Qt files and fight the compiler with #ifdefs until it builds with all dependencies in place.
Linux(ness) - I've had to disable all Linux/Windows things that are not supported in my target OS: threads, sockets, processes. Even the timers are slightly different.
Tips:
Start small : I compiled QtCore as a standard lib within my IDE, next up is QtGui which is a behemoth compared to QtCore.
I plan to run only a single QThread, so I have to artificially made a Thread object to avoid null pointers. You cannot compile out Thread information as it is key to all QObjects.
So far I have an qeventloop running within a qcoreapplication.
I wrote some inline assembly but had serious difficulties with my IDE and compilation. I left it in C++ and let the assembler handle it for me. Because I am single-threaded, I am not too concerned with shared data/ exclusive access as required by the atomic operations.
I would like to experiment with ideas about distributed file synchronization/replication. To make it efficient when the user is working, I would like to implement some kind of daemon to monitor changes in some directory (e.g. /home/user/dirToBeMonitored or c:\docs and setts\user\dirToBeMonitored). So, I could be able to know which filename was added/changed/deleted at every time (or within a reasonable interval).
Is this possible with any high-medium level language?. Do you know some API (and in which language?) to do this?
Thanks.
The APIs are totally different for Windows, Linux, Mac OS X, and any other Unix you can name, it seems. I don't know of any cross-platform library that handles this in a consistent way.
A bonified answer, albeit one that requires a largish library dependency (well-worth it IMO)!
QT provides the QFileSystemwatcher class, which uses the native mechanism of the underlying platform.
Even better, you can use the QT language bindings for Python or Ruby. Here is a simple PyQT4 application which uses QFileSystemWatcher.
Notes
A good reference on on creating deployable PyQT4 apps, especially on OSX but should work for Windows also.
Same solution previously posted here.
Other cross-platform toolkits may also do the trick (for example Gnome's GIO has GFileMonitor, although it is UNIX only and doesn't support OSX's FSEvents mechanism afaik).
In Linux it is called inotify.
And on OS X it's called fsevents. It's an OS-level API, so it's easiest to access from C or C++. It should be accessible from nearly any language, although bindings for your preferred language may not have been written yet.