/* Support for dynamic loading of extension modules */

#include "Python.h"

#include "importdl.h"

#include <sys/types.h>

#include <sys/stat.h>

#if defined(__NetBSD__)

#include <sys/param.h>

#if (NetBSD < 199712)

#include <nlist.h>

#include <link.h>

#define dlerror() "error in dynamic linking"

#endif

#endif /* NetBSD */

#ifdef HAVE_DLFCN_H

#include <dlfcn.h>

#else

#if defined(PYOS_OS2) && defined(PYCC_GCC)

#include "dlfcn.h"

#endif

#endif

#if (defined(__OpenBSD__) || defined(__NetBSD__)) && !defined(__ELF__)

#define LEAD_UNDERSCORE "_"

#else

#define LEAD_UNDERSCORE ""

#endif

const struct filedescr _PyImport_DynLoadFiletab[] = {

#ifdef __CYGWIN__

	{".dll", "rb", C_EXTENSION},

	{"module.dll", "rb", C_EXTENSION},

#else

#if defined(PYOS_OS2) && defined(PYCC_GCC)

	{".pyd", "rb", C_EXTENSION},

	{".dll", "rb", C_EXTENSION},

#else

#ifdef __VMS

        {".exe", "rb", C_EXTENSION},

        {".EXE", "rb", C_EXTENSION},

        {"module.exe", "rb", C_EXTENSION},

        {"MODULE.EXE", "rb", C_EXTENSION},

#else

	{".so", "rb", C_EXTENSION},

	{"module.so", "rb", C_EXTENSION},

#endif

#endif

#endif

	{0, 0}

};

static struct {

	dev_t dev;

#ifdef __VMS

	ino_t ino[3];

#else

	ino_t ino;

#endif

	void *handle;

} handles[128];

static int nhandles = 0;

dl_funcptr _PyImport_GetDynLoadFunc(const char *fqname, const char *shortname,

				    const char *pathname, FILE *fp)

{

	dl_funcptr p;

	void *handle;

	char funcname[258];

	char pathbuf[260];

        int dlopenflags=0;

	if (strchr(pathname, '/') == NULL) {

		/* Prefix bare filename with "./" */

		PyOS_snprintf(pathbuf, sizeof(pathbuf), "./%-.255s", pathname);

		pathname = pathbuf;

	}

	PyOS_snprintf(funcname, sizeof(funcname), 

		      LEAD_UNDERSCORE "init%.200s", shortname);

	if (fp != NULL) {

		int i;

		struct stat statb;

		fstat(fileno(fp), &statb);

		for (i = 0; i < nhandles; i++) {

			if (statb.st_dev == handles[i].dev &&

			    statb.st_ino == handles[i].ino) {

				p = (dl_funcptr) dlsym(handles[i].handle,

						       funcname);

				return p;

			}

		}

		if (nhandles < 128) {

			handles[nhandles].dev = statb.st_dev;

#ifdef __VMS

			handles[nhandles].ino[0] = statb.st_ino[0];

			handles[nhandles].ino[1] = statb.st_ino[1];

			handles[nhandles].ino[2] = statb.st_ino[2];

#else

			handles[nhandles].ino = statb.st_ino;

#endif

		}

	}

#if !(defined(PYOS_OS2) && defined(PYCC_GCC))

        dlopenflags = PyThreadState_GET()->interp->dlopenflags;

#endif

	if (Py_VerboseFlag)

		PySys_WriteStderr("dlopen(\"%s\", %x);\n", pathname, 

				  dlopenflags);

#ifdef __VMS

	/* VMS currently don't allow a pathname, use a logical name instead */

	/* Concatenate 'python_module_' and shortname */

	/* so "import vms.bar" will use the logical python_module_bar */

	/* As C module use only one name space this is probably not a */

	/* important limitation */

	PyOS_snprintf(pathbuf, sizeof(pathbuf), "python_module_%-.200s", 

		      shortname);

	pathname = pathbuf;

#endif

	handle = dlopen(pathname, dlopenflags);

	if (handle == NULL) {

		const char *error = dlerror();

		if (error == NULL)

			error = "unknown dlopen() error";

		PyErr_SetString(PyExc_ImportError, error);

		return NULL;

	}

	if (fp != NULL && nhandles < 128)

		handles[nhandles++].handle = handle;

	p = (dl_funcptr) dlsym(handle, funcname);

	return p;

}