[Pythonmac-SIG] dynload_next

Sat, 26 Jan 2002 22:24:04 -0500 (EST)

  This message is in MIME format.  The first part should be readable text,
  while the remaining parts are likely unreadable without MIME-aware tools.
  Send mail to mime@docserver.cac.washington.edu for more info.

---2138096204-1237206507-1012101844=:13414
Content-Type: TEXT/PLAIN; charset=US-ASCII

On Sat, 26 Jan 2002, Marcel Prastawa wrote:

> I've got dynload_next working with PyOpenGL!
>
> I used libdl's dlopen.c as a reference. The problem appears to be caused
> by the use of NSLookupAndBindSymbol(). I have switched to using
> NSLookupSymbolInModule() instead. I also commented out the quick return.
>
> I have attached the diff file. It is also available at:
> http://www.cs.unc.edu/~prastawa/macosx/dynload_next.diff
>
> Can any of you try it out and make sure it doesn't break anything?
> I haven't encountered any problems so far.
>

Marcel -- I kept getting error trying to apply the patch, but it
was just like one of the things I had already tried which wasn't
working for me.  Actually I tried two variations -- one the same
as yours and another also setting  NSLINKMODULE_OPTION_PRIVATE.
 version 1 didn't fix the problem for me.
 version 2 didn't work.

Did you change the link options to get it to work for you ?
( two-level-namespace ? )

(Also, I believe you used my NSLinkEditError patch, which I'm sorry to say
 was very sloppily done for debugging purposes. All those strcat()'s
 onto an existing constant string were a big mistake! )

I have, however, cleaned out some of the cruft and gotten a version
that works for me. Could a few of you folks who have had these
problems give this a try and tell me if it fixes things for you?

This one does set the PRIVATE option -- in the Python module API,
all of the exported functions go into the tables built and exported
by the init module, and the init function pointer is returned at the
end. So it really shouldn't need any global symbols to be bound
into the main program. It also seems to work for the Carbon modules.

My earlier attempt to use the PRIVATE option failed because the
second check for NSIsSymbolNameDefined() took not finding it as
a failure and bailed out. I had to cut that test out. That also
makes the first test (before the DEBUG) never pass, so the
warning doesn't even print for the 'import time, package.time'
test.

So far, this has worked for me on everything I've thrown at it.
If it works for everyone else, I'll permanenly pull out the
other non-functional code and submit it.

-- Steve Majewski

/* Support for dynamic loading of extension modules */

#include "Python.h"
#include "importdl.h"

#include <mach-o/dyld.h>

#define DEBUG 1
#define PRIVATE NSLINKMODULE_OPTION_PRIVATE
#define OTHER_OPTIONS  NSLINKMODULE_OPTION_BINDNOW|NSLINKMODULE_OPTION_RETURN_ON_ERROR
#define LINK_MODULE_OPTIONS  (PRIVATE | OTHER_OPTIONS)

const struct filedescr _PyImport_DynLoadFiletab[] = {
	{".so", "rb", C_EXTENSION},
	{"module.so", "rb", C_EXTENSION},
	{0, 0}
};

char errmessage[400];

dl_funcptr _PyImport_GetDynLoadFunc(const char *fqname, const char *shortname,
				    const char *pathname, FILE *fp)
{

	NSObjectFileImageReturnCode rc;
	NSObjectFileImage image;
	NSModule newModule;
	NSSymbol theSym;
	const char *errString;

	dl_funcptr p = NULL;
	char funcname[258];

	PyOS_snprintf(funcname, sizeof(funcname), "_init%.200s", shortname);

	if (NSIsSymbolNameDefined(funcname)) {
#ifdef DEBUG
	  fprintf(stderr,"[!warning] %s already defined.\n", funcname );
#endif
	}

	rc = NSCreateObjectFileImageFromFile(pathname, &image);
	switch(rc) {
	    default:
	    case NSObjectFileImageFailure:
	    case NSObjectFileImageFormat:
	    /* for these a message is printed on stderr by dyld */
		errString = "Can't create object file image";
		break;
	    case NSObjectFileImageSuccess:
		errString = NULL;
		break;
	    case NSObjectFileImageInappropriateFile:
		errString = "Inappropriate file type for dynamic loading";
		break;
	    case NSObjectFileImageArch:
		errString = "Wrong CPU type in object file";
		break;
	    case NSObjectFileImageAccess:
		errString = "Can't read object file (no access)";
		break;
	}
	if (errString == NULL) {
	  newModule = NSLinkModule(image, pathname,LINK_MODULE_OPTIONS);
	    if (!newModule) {
	      int errNo;
	      char *filename, *errinfo;
	      NSLinkEditErrors c;
	      errString = "Failure linking new module";
	      NSLinkEditError( &c, &errNo, &filename, &errinfo );
	      sprintf( errmessage, "%s. %s\n%s",
		       errString, filename, errinfo );
	      errString = errmessage;
	    }
	}
	if (errString != NULL) {
		PyErr_SetString(PyExc_ImportError, errString);
		return NULL;
	}
#ifdef NONONO
	if (!NSIsSymbolNameDefined(funcname)) {
		/* UnlinkModule() isn't implemented in current versions,
		   but calling it does no harm */
		NSUnLinkModule(newModule, FALSE);
		PyErr_Format(PyExc_ImportError,
			     "Loaded module does not contain symbol %.200s",
			     funcname);
		return NULL;
	}
#endif
	/*	theSym = NSLookupAndBindSymbol(funcname); */
	theSym = NSLookupSymbolInModule(newModule,funcname);
	p = (dl_funcptr)NSAddressOfSymbol(theSym);

	return p;
}

---2138096204-1237206507-1012101844=:13414
Content-Type: TEXT/PLAIN; charset=US-ASCII; name="dynload_next.c"
Content-Transfer-Encoding: BASE64
Content-ID: <Pine.OSX.4.43.0201262224040.13414@d-128-61-180.bootp.virginia.edu>
Content-Description: 
Content-Disposition: attachment; filename="dynload_next.c"
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---2138096204-1237206507-1012101844=:13414--