/* 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;}