[SciPy-user] [weave] newbie : compilation issue

[Eric Jones]

Hey JBR,

The docs are out of date compared to the CVS.  I don't have all your source to check against, but I would expect the following is fairly close to what you want.  Weave sould do all the work translating Python variables to C/C++ for you, at least in the case of "standard" argument types which you are using, so the PyObject* stuff you have in your code isn't necessary.

If the code below doesn't work, attach the C files your using and I see what I can do to help out.

eric

from weave import ext_tools

def build_date():
    """contruit le module d'extension
    """
    module = ext_tools.ext_module('date_ext')

    #fonction de positionnement dans un fichier
    """
    positionne_flot a 4 arguments, un p_pointeur de fichier en lecture,
    un p_pointeur de fichier en écriture (log), un caractère et une
    date (double)
    """

    fichier_date_c = open('date.c','r')
    code_date_c = fichier_date_c.read()
    
    # arguments
    fichier_src = fichier_date_c
    fichier_log = open('log.log','w')
    pdt = 'a'
    date = 1.23

    ext_code = "return_val = positionne_flot(&p_file,pdt[0],date,&p_log);"
    
    fonction = ext_tools.ext_function('c_positionne_flot',ext_code,['fichier_src','pdt','date','fichier_log'])
    fonction.customize.add_support_code(code_date_c)
    module.add_function(fonction)
    module.compile()

try:
    import date_ext
except ImportError:
    build_date()
    import date_ext


Jean-Baptiste Richet - AREAS <jb.richet.areas at normandnet.fr> wrote ..
> Hi,
> 
> I'm trying to have weave take my C functions into Python. I try to build
> a module with ext_tools, but I don't know much about writing Python 
> extensions (actually, nothing). I just try to guess how to do from the
> tutorial and its examples. But of course it doesn't work.
> First, let me give you the error message:
> =============================
> jb at areas:~/routines/commun$ python ext_date.py
> /home/jb/routines/commun/date_ext.cpp: In function `struct PyObject * 
> c_positionne_flot(PyObject *, PyObject *, PyObject *)':
> /home/jb/routines/commun/date_ext.cpp:925: `raw_locals' undeclared 
> (first use this function)
> /home/jb/routines/commun/date_ext.cpp:925: (Each undeclared identifier
> is reported only once
> /home/jb/routines/commun/date_ext.cpp:925: for each function it appears
> in.)
> /home/jb/routines/commun/date_ext.cpp:925: `raw_globals' undeclared 
> (first use this function)
> /home/jb/routines/commun/date_ext.cpp:925: implicit declaration of 
> function `int get_variable(...)'
> Traceback (most recent call last):
>   File "ext_date.py", line 50, in ?
>     build_date()
>   File "ext_date.py", line 45, in build_date
>     module.compile()
>   File "/usr/local/lib/python2.3/site-packages/weave/ext_tools.py", line
> 349, in compile
>     verbose = verbose, **kw)
>   File "/usr/local/lib/python2.3/site-packages/weave/build_tools.py", 
> line 194,
> in build_extension
>     setup(name = module_name, ext_modules = [ext],verbose=verb)
>   File "/usr/local/lib/python2.3/distutils/core.py", line 166, in setup
>     raise SystemExit, "error: " + str(msg)
> weave.build_tools.CompileError: error: command 'gcc' failed with exit 
> status 1
> jb at areas:~/routines/commun$
> ====================================
> 
> Maybe I lack some #include or something like that ?
> The line :
>     PyObject* py_file = get_variable("fichier_src",raw_locals,raw_globals);
> from which the error is raised, was found in the weave tutorial about file
> conversions. I can hardly understand what it does. 
> Here is the code at the bottom of the message. 
> [I hesitate to give the date.c code, or the date_ext.cpp code, it's a bit
> long, and there's no compile error from it. If you need it to help me,
> please tell me.]
> 
> thanks for your help,
> JBR
> 
> ================ ext_date.py =========================
> # -*- coding: UTF-8 -*-
> 
> #test d'utilisation de weave pour créer une bibliothèque
> 
> from weave import ext_tools
> 
> fichier_date_c = open('date.c','r')
> code_date_c = fichier_date_c.read()
> 
> fichier_src = fichier_date_c
> fichier_log = open('log.log','w')
> pdt = 'a'
> date = 1.23
> def build_date():
>     """contruit le module d'extension
>     """
>     module = ext_tools.ext_module('date_ext')
> 
>     #fonction de positionnement dans un fichier
>     """
>     positionne_flot a 4 arguments, un p_pointeur de fichier en lecture,
>     un p_pointeur de fichier en écriture (log), un caractère et une
>     date (double)
>     """
>     ext_code = """
>     PyObject* py_file = get_variable("fichier_src",raw_locals,raw_globals);
>     FILE* file = py_to_file(py_file,"fichier_src");
>     PyObject* py_log = get_variable("fichier_log",raw_locals,raw_globals);
>     FILE* log = py_to_file(py_log,"fichier_log");
>     
>     FILE** p_file = &file;
>     FILE** p_log = &log;
> 
>     char c_pdt = std::string(pdt).c_str()[0];
>     
>     int resultat;
> 
>     resultat = positionne_flot(p_file,c_pdt,date,p_log);
> 
>     return_val = Py::new_reference_to(Py::Int(resultat));
>     """
>     fonction = ext_tools.ext_function('c_positionne_flot',ext_code,['fichier_src','pdt','date','fichier_log'])
>     fonction.customize.add_support_code(code_date_c)
>     module.add_function(fonction)
>     module.compile()
> 
> try:
>     import date_ext
> except ImportError:
>     build_date()
>     import date_ext
> =============================================
> 
> -- 
> Jean-Baptiste Richet
> AREAS
> _________________________________
> Association régionale pour l'étude
> et l'amélioration des sols
> 2, avenue Foch
> 76460 Saint Valéry en Caux
> tél : +33 2 35 97 25 12
> fax : +33 2 35 97 25 73
> _________________________________
> 
> 
> _______________________________________________
> SciPy-user mailing list
> SciPy-user at scipy.net
> http://www.scipy.net/mailman/listinfo/scipy-user