I'm trying to write a rake task that can perform a guided search on the user's system for specific system libraries. The basic idea is simple enough (in semi-pseudo-code):
def find_lib names, paths
foreach name, path do
return { :name => name, :path => path } if File.exists? File.join(path, name)
end
return false
end
find_lib ['mylib1.2', 'mylib12'], ['/usr/lib', '/usr/local/lib']
My actual implementation is a little more elegant, but this shows the basic idea. However, I would like to make this OS agnostic, which throws a few big wrenches into the gears. Each operating system has potentially different prefixes and extensions for a library. For instance, a shared library could be ".dll", ".so', or ".dylib" depending on the current system. So far, I've come up with a solution that involves building a map of prefixes/extensions based on the current operating system:
settings = {}
settings[:dylib_ext] = OS.windows? && ".dll" ||
OS.mac? && ".dylib" ||
".so"
This works to some extent, although it only covers the dynamic library case, and also relies on an external gem "OS", which I was trying to avoid.
Does anyone know a better way of accomplishing such a task, or if it is a solved problem (via another gem perhaps)? The main thing I'm concerned about is the map, which could get very cumbersome (not to mention that detecting the correct operating system is rather tedious at best, especially if you were to throw in cygwin or mingw).
After some thought, it seems that I have been too specific as to the user's current operating system, while what I really have wanted to determine has always been what functionality the user's system supports... The approach that I ended up using was to determine a list of possible prefix/suffix combinations, and to check each of those.
Related
I'm using Python 2.6 and PyGTK 2.22.6 from the all-in-one installer on Windows XP, trying to build a single-file executable (via py2exe) for my app.
My problem is that when I run my app as a script (ie. not built into an .exe file, just as a loose collection of .py files), it uses the native-looking Windows theme, but when I run the built exe I see the default GTK theme.
I know that this problem can be fixed by copying a bunch of files into the dist directory created by py2exe, but everything I've read involves manually copying the data, whereas I want this to be an automatic part of the build process. Furthermore, everything on the topic (including the FAQ) is out of date - PyGTK now keeps its files in C:\Python2x\Lib\site-packages\gtk-2.0\runtime\..., and just copying the lib and etc directories doesn't fix the problem.
My questions are:
I'd like to be able to programmatically find the GTK runtime data in setup.py rather than hard coding paths. How do I do this?
What are the minimal resources I need to include?
Update: I may have almost answered #2 by trial-and-error. For the "wimp" (ie. MS Windows) theme to work, I need the files from:
runtime\lib\gtk-2.0\2.10.0\engines\libwimp.dll
runtime\etc\gtk-2.0\gtkrc
runtime\share\icons\*
runtime\share\themes\MS-Windows
...without the runtime prefix, but otherwise with the same directory structure, sitting directly in the dist directory produced by py2exe. But where does the 2.10.0 come from, given that gtk.gtk_version is (2,22,0)?
Answering my own question here, but if anyone knows better feel free to answer too. Some of it seems quite fragile (eg. version numbers in paths), so comment or edit if you know a better way.
1. Finding the files
Firstly, I use this code to actually find the root of the GTK runtime. This is very specific to how you install the runtime, though, and could probably be improved with a number of checks for common locations:
#gtk file inclusion
import gtk
# The runtime dir is in the same directory as the module:
GTK_RUNTIME_DIR = os.path.join(
os.path.split(os.path.dirname(gtk.__file__))[0], "runtime")
assert os.path.exists(GTK_RUNTIME_DIR), "Cannot find GTK runtime data"
2. What files to include
This depends on (a) how much of a concern size is, and (b) the context of your application's deployment. By that I mean, are you deploying it to the whole wide world where anyone can have an arbitrary locale setting, or is it just for internal corporate use where you don't need translated stock strings?
If you want Windows theming, you'll need to include:
GTK_THEME_DEFAULT = os.path.join("share", "themes", "Default")
GTK_THEME_WINDOWS = os.path.join("share", "themes", "MS-Windows")
GTK_GTKRC_DIR = os.path.join("etc", "gtk-2.0")
GTK_GTKRC = "gtkrc"
GTK_WIMP_DIR = os.path.join("lib", "gtk-2.0", "2.10.0", "engines")
GTK_WIMP_DLL = "libwimp.dll"
If you want the Tango icons:
GTK_ICONS = os.path.join("share", "icons")
There is also localisation data (which I omit, but you might not want to):
GTK_LOCALE_DATA = os.path.join("share", "locale")
3. Piecing it together
Firstly, here's a function that walks the filesystem tree at a given point and produces output suitable for the data_files option.
def generate_data_files(prefix, tree, file_filter=None):
"""
Walk the filesystem starting at "prefix" + "tree", producing a list of files
suitable for the data_files option to setup(). The prefix will be omitted
from the path given to setup(). For example, if you have
C:\Python26\Lib\site-packages\gtk-2.0\runtime\etc\...
...and you want your "dist\" dir to contain "etc\..." as a subdirectory,
invoke the function as
generate_data_files(
r"C:\Python26\Lib\site-packages\gtk-2.0\runtime",
r"etc")
If, instead, you want it to contain "runtime\etc\..." use:
generate_data_files(
r"C:\Python26\Lib\site-packages\gtk-2.0",
r"runtime\etc")
Empty directories are omitted.
file_filter(root, fl) is an optional function called with a containing
directory and filename of each file. If it returns False, the file is
omitted from the results.
"""
data_files = []
for root, dirs, files in os.walk(os.path.join(prefix, tree)):
to_dir = os.path.relpath(root, prefix)
if file_filter is not None:
file_iter = (fl for fl in files if file_filter(root, fl))
else:
file_iter = files
data_files.append((to_dir, [os.path.join(root, fl) for fl in file_iter]))
non_empties = [(to, fro) for (to, fro) in data_files if fro]
return non_empties
So now you can call setup() like so:
setup(
# Other setup args here...
data_files = (
# Use the function above...
generate_data_files(GTK_RUNTIME_DIR, GTK_THEME_DEFAULT) +
generate_data_files(GTK_RUNTIME_DIR, GTK_THEME_WINDOWS) +
generate_data_files(GTK_RUNTIME_DIR, GTK_ICONS) +
# ...or include single files manually
[
(GTK_GTKRC_DIR, [
os.path.join(GTK_RUNTIME_DIR,
GTK_GTKRC_DIR,
GTK_GTKRC)
]),
(GTK_WIMP_DIR, [
os.path.join(
GTK_RUNTIME_DIR,
GTK_WIMP_DIR,
GTK_WIMP_DLL)
])
]
)
)
In the application that I am developing (using C++ and Qt), I am using QApplication::applicationDirPath() to access some resources, with respect of the application's path.
As an example, since I want to open a HTML manual from the application, I act this way:
void MainWindow::on_actionHelp_triggered()
{
QString link = QApplication::applicationDirPath() + "/Guide/guide.html";
bool r = QDesktopServices::openUrl(QUrl::fromLocalFile(link));
}
This snippet works if the project's structure presents the path "ProjectName/bin/Release/Guide/guide.html" (since the .exe file is in "ProjectName/bin/Release/AppName.exe").
But what can I do to refer to a higher-directory-level resource? As an example, I wish my HTML file to be in "ProjectName/data/Guide/guide.html". But this way, it seems not possible to compose the path in the way I'm acting.
EDIT: After #olive's comment, I wish to clarify a thing:
"Why am I not using '../'?"
Because it won't work from Visual Studio, where I am massively launch the application to test it. From VS, in fact, I shall use "../data/Guide/guide.html", when "from the outside", I'd have to do "../../data/Guide/guide.html".
That's why (I think) QApplication::applicationDirPath() exists. However, I am not an expert, so don't blame me and correct any eventual mistake of mine, please!
Just use ... QApplication::applicationDirPath() + "/../../data/Guide/guide.html" is perfectly valid path!
Of course there is another problem. When the application is installed, the relative path will probably be different again. You either need to configure the paths in visual studio so that the relative path works both during development and after deployment, or you need to detect the layout.
I am working on a plugin which will have its own plugins to handle various events.
Now I'm thinking of enabling this plugins to add their own "commands". But I wonder how to treat that most efficiently. I have a list of my own commands which I search in the article anyway. Should I then just trigger a DoWhatYouWant($article)-event - or, since I do the searching (and parsing of params) anyway, perhaps I could build a global command-list and then trigger an "ExecuteCommand($article,$cmd,$params)"-event? Sounds nicer, but then (I think) I'd have to build this command-list (so that my program know what to look for), so every plugin would have to somehow 'advertise' what it could do, i.e. the names of commands it could handle - and I have no idea how that could be done.
Or is there a better (more standardized?) approach?
If you import your plugins trough the plugin helper
JPluginHelper::importPlugin('mycmdplugins');
then you can get all available commands which are supported by your sub plugins like
$cmds = JDispatcher::getInstance()->trigger('onMyAwesomeCmds');
With the $cmds variable you know now which commands are supported by the sub plugins and you can parse the article for them. Then you can do
foreach ($cmds as $cmd) {
preg_match_all("{".$cmd."*}", $article->text, $matches, PREG_SET_ORDER);
if (!empty($matches)) {
JDispatcher::getInstance()->trigger('onMyAwesome'.ucfirst($cmd), array($article, $params));
}
}
To eliminate more repeating tasks I suggest that the additional plugins will extend a base class from your plugins folder.
So...I have a kernel mode component and a user mode component I'm putting together using the turnkey build environment of the NT DDK 7.1.0. The kernel component is all .c/.h/.rc files. The user mode component is .cpp/.c/.h/.rc files.
At first it seemed simplest to use build for both, as I saw you could modify the ./sources file of the user mode component to say something like:
TARGETNAME = MyUserModeComponent
TARGETTYPE = PROGRAM
UMTYPE = windows
UMENTRY = winmain
USE_MSVCRT = 1
That didn't seem to cause a problem and so I was pleased, until I tried to #include <string> (or <memory>, or whatever) Doesn't find that stuff:
error C1083: Cannot open include file: 'string': No such file or directory
Still, it's compiling the user mode piece with C++ language semantics. But how do I get the standard includes to work?
I don't technically need to use the DDK build tool for the user mode piece. I could make a visual studio solution. I'm a bit wary as I have bumped into other annoyances, like the fact that the DDK uses __stdcall instead of __cdecl by default... and there isn't any pragma or compiler switch to override this. You literally have to go into each declaration you care about and change it, assuming you have source to do so. :-/
I'm starting to wonder if this is just a fractal descent into "just because you CAN doesn't mean you SHOULD build user mode apps with the DDK. Here be dragons." So my question isn't just about this particular technical hurdle, but rather if I should abandon the idea of building a C++ user mode component with the DDK tools...just because the kernel component is pure C.
To build a user mode program with WINDDK you need to add some variables to your SOURCES file:
386_STDCALL=0 to use cdecl calling convention by default
USE_STL=1 to use STL
USE_NATIVE_EH=1 to add a support for exception handling
Everything else you already have.
I'll put my full SOURCES file for reference:
TARGETNAME = MyUserModeComponent
TARGETTYPE = PROGRAM
TARGETPATH = obj
UMTYPE = console
UMENTRY = main
USE_MSVCRT = 1
USE_NATIVE_EH=1
USE_STL=1
386_STDCALL=0
SOURCES= main.cpp
And main.cpp:
#include <iostream>
#include <string>
using namespace std;
int main()
{
string s = "bla bla bla!";
cout << s;
return 0;
}
Have fun!
Quick Answer
Abandon the idea of building user-mode components with DDK tools (although I find the concept fascinating :-P)
Your kernel mode component should be built separately from the user mode components as a matter of good practice.
Vague thoughts
Off the top of my head, and this really speaking from limited experience...there are a lot of subtle differences that can creep up if you try to mix the two together.
Using your own example of __cdecl vs __stdcall; You have two different calling conventions. _cdecl is all kernel stuff and all of the C++ methods are wrapped around in WINAPI (_stdcall) passing conventions and __stdcall will clean do auto stack clean up and expect frame pointers inserted all over the place. And if you by accident use compiler options to trigger a __fastcall, it would be a pain to debug.
You can definitely hack something together, but do you really want to keep track of that in your user-space code and build environment? UGH I say.
Unless you have very specific engineering reasons to mix the two environments, (and no a unified build experience is not a valid reason, because you can get that from a batch file called buildall.bat) I say use the separate toolchains.
I'm looking for a way to register somthing like an end-build callback in scons. For example, I'm doing something like this right now:
def print_build_summary():
failures = SCons.Script.GetBuildFailures()
notifyExe = 'notify-send '
if len(failures) > 0:
notifyExe = notifyExe + ' --urgency=critical Build Failed'
else:
notifyExe = notifyExe + ' --urgency=normal Build Succeed'
os.system(notifyExe)
atexit.register(print_build_summary)
This only works in non-interactive mode. I'd like to be able to pop up something like this at the end of every build, specifically, when running multiple 'build' commands in an interactive scons session.
The only suggestions I've found, looking around, seem to be to use the dependency system or the AddPostAction call to glom this on. It doesn't seem quite right to me to do it that way, since it's not really a dependency (it's not even really a part of the build, strictly speaking) - it's just a static bit of code that needs to be run at the end of every build.
Thanks!
I don't think there's anything wrong with using the dependency system to resolve this. This is how I normally do it:
def finish( target, source, env ):
raise Exception( 'DO IT' )
finish_command = Command( 'finish', [], finish )
Depends( finish_command, DEFAULT_TARGETS )
Default( finish_command )
This creates a command that depends on the default targets for it's execution (so you know it'll always run last - see DEFAULT_TARGETS in scons manual). Hope this helps.
Ive been looking into this and havent found that SCons offers anything that would help. This seems like quite a usefull feature, maybe the SCons developers are watching these threads and will take the suggestion...
I looked at the source code and figured out how to do it. I'll try to suggest this change to the SCons developers on scons.org.
If you're interested, the file is engine/SCons/Script/Main.py, and the function is _build_targets(). At the end of this funcion, you would simply need to add a call to a user supplied callback. Of course this solution would not be very useful if you build on several different machines in your network, since you would have to port the change everywhere its needed, but if you're only building on one machine, then maybe you could make the change until/if SCons officially provides a solution.
Let me know if you need help implementing the change, and I'll see what I can do.
Another option would be to wrap the call to SCons, and have the wrapper script perform the desired actions, but that wouldnt help in SCons interactive mode.
Hope this helps,
Brady
EDIT:
I create a feature request for this: http://scons.tigris.org/issues/show_bug.cgi?id=2834