1
2 /* Support for dynamic loading of extension modules */
3
4 #include "Python.h"
5 #include "pycore_interp.h" // _PyInterpreterState.dlopenflags
6 #include "pycore_pystate.h" // _PyInterpreterState_GET()
7 #include "importdl.h"
8
9 #include <sys/types.h>
10 #include <sys/stat.h>
11
12 #if defined(__NetBSD__)
13 #include <sys/param.h>
14 #if (NetBSD < 199712)
15 #include <nlist.h>
16 #include <link.h>
17 #define dlerror() "error in dynamic linking"
18 #endif
19 #endif /* NetBSD */
20
21 #ifdef HAVE_DLFCN_H
22 #include <dlfcn.h>
23 #endif
24
25 #if (defined(__OpenBSD__) || defined(__NetBSD__)) && !defined(__ELF__)
26 #define LEAD_UNDERSCORE "_"
27 #else
28 #define LEAD_UNDERSCORE ""
29 #endif
30
31 /* The .so extension module ABI tag, supplied by the Makefile via
32 Makefile.pre.in and configure. This is used to discriminate between
33 incompatible .so files so that extensions for different Python builds can
34 live in the same directory. E.g. foomodule.cpython-32.so
35 */
36
37 const char *_PyImport_DynLoadFiletab[] = {
38 #ifdef __CYGWIN__
39 ".dll",
40 #else /* !__CYGWIN__ */
41 "." SOABI ".so",
42 #ifdef ALT_SOABI
43 "." ALT_SOABI ".so",
44 #endif
45 ".abi" PYTHON_ABI_STRING ".so",
46 ".so",
47 #endif /* __CYGWIN__ */
48 NULL,
49 };
50
51
52 dl_funcptr
_PyImport_FindSharedFuncptr(const char * prefix,const char * shortname,const char * pathname,FILE * fp)53 _PyImport_FindSharedFuncptr(const char *prefix,
54 const char *shortname,
55 const char *pathname, FILE *fp)
56 {
57 dl_funcptr p;
58 void *handle;
59 char funcname[258];
60 char pathbuf[260];
61 int dlopenflags=0;
62
63 if (strchr(pathname, '/') == NULL) {
64 /* Prefix bare filename with "./" */
65 PyOS_snprintf(pathbuf, sizeof(pathbuf), "./%-.255s", pathname);
66 pathname = pathbuf;
67 }
68
69 PyOS_snprintf(funcname, sizeof(funcname),
70 LEAD_UNDERSCORE "%.20s_%.200s", prefix, shortname);
71
72 if (fp != NULL) {
73 struct _Py_stat_struct status;
74 if (_Py_fstat(fileno(fp), &status) == -1)
75 return NULL;
76 }
77
78 dlopenflags = _PyInterpreterState_GET()->dlopenflags;
79
80 handle = dlopen(pathname, dlopenflags);
81
82 if (handle == NULL) {
83 PyObject *mod_name;
84 PyObject *path;
85 PyObject *error_ob;
86 const char *error = dlerror();
87 if (error == NULL)
88 error = "unknown dlopen() error";
89 error_ob = PyUnicode_DecodeLocale(error, "surrogateescape");
90 if (error_ob == NULL)
91 return NULL;
92 mod_name = PyUnicode_FromString(shortname);
93 if (mod_name == NULL) {
94 Py_DECREF(error_ob);
95 return NULL;
96 }
97 path = PyUnicode_DecodeFSDefault(pathname);
98 if (path == NULL) {
99 Py_DECREF(error_ob);
100 Py_DECREF(mod_name);
101 return NULL;
102 }
103 PyErr_SetImportError(error_ob, mod_name, path);
104 Py_DECREF(error_ob);
105 Py_DECREF(mod_name);
106 Py_DECREF(path);
107 return NULL;
108 }
109 p = (dl_funcptr) dlsym(handle, funcname);
110 return p;
111 }
112