1
2 /* Support for dynamic loading of extension modules on Mac OS X
3 ** All references to "NeXT" are for historical reasons.
4 */
5
6 #include "Python.h"
7 #include "importdl.h"
8
9 #include <mach-o/dyld.h>
10
11 const struct filedescr _PyImport_DynLoadFiletab[] = {
12 {".so", "rb", C_EXTENSION},
13 {"module.so", "rb", C_EXTENSION},
14 {0, 0}
15 };
16
17 /*
18 ** Python modules are Mach-O MH_BUNDLE files. The best way to load these
19 ** is each in a private namespace, so you can load, say, a module bar and a
20 ** module foo.bar. If we load everything in the global namespace the two
21 ** initbar() symbols will conflict.
22 ** However, it seems some extension packages depend upon being able to access
23 ** each others' global symbols. There seems to be no way to eat our cake and
24 ** have it, so the USE_DYLD_GLOBAL_NAMESPACE define determines which behaviour
25 ** you get.
26 */
27
28 #ifdef USE_DYLD_GLOBAL_NAMESPACE
29 #define LINKOPTIONS NSLINKMODULE_OPTION_BINDNOW|NSLINKMODULE_OPTION_RETURN_ON_ERROR
30 #else
31 #define LINKOPTIONS NSLINKMODULE_OPTION_BINDNOW| \
32 NSLINKMODULE_OPTION_RETURN_ON_ERROR|NSLINKMODULE_OPTION_PRIVATE
33 #endif
_PyImport_GetDynLoadFunc(const char * fqname,const char * shortname,const char * pathname,FILE * fp)34 dl_funcptr _PyImport_GetDynLoadFunc(const char *fqname, const char *shortname,
35 const char *pathname, FILE *fp)
36 {
37 dl_funcptr p = NULL;
38 char funcname[258];
39 NSObjectFileImageReturnCode rc;
40 NSObjectFileImage image;
41 NSModule newModule;
42 NSSymbol theSym;
43 const char *errString;
44 char errBuf[512];
45
46 PyOS_snprintf(funcname, sizeof(funcname), "_init%.200s", shortname);
47
48 #ifdef USE_DYLD_GLOBAL_NAMESPACE
49 if (NSIsSymbolNameDefined(funcname)) {
50 theSym = NSLookupAndBindSymbol(funcname);
51 p = (dl_funcptr)NSAddressOfSymbol(theSym);
52 return p;
53 }
54 #endif
55 rc = NSCreateObjectFileImageFromFile(pathname, &image);
56 switch(rc) {
57 default:
58 case NSObjectFileImageFailure:
59 case NSObjectFileImageFormat:
60 /* for these a message is printed on stderr by dyld */
61 errString = "Can't create object file image";
62 break;
63 case NSObjectFileImageSuccess:
64 errString = NULL;
65 break;
66 case NSObjectFileImageInappropriateFile:
67 errString = "Inappropriate file type for dynamic loading";
68 break;
69 case NSObjectFileImageArch:
70 errString = "Wrong CPU type in object file";
71 break;
72 case NSObjectFileImageAccess:
73 errString = "Can't read object file (no access)";
74 break;
75 }
76 if (errString == NULL) {
77 newModule = NSLinkModule(image, pathname, LINKOPTIONS);
78 if (newModule == NULL) {
79 int errNo;
80 const char *fileName, *moreErrorStr;
81 NSLinkEditErrors c;
82 NSLinkEditError( &c, &errNo, &fileName, &moreErrorStr );
83 PyOS_snprintf(errBuf, 512, "Failure linking new module: %s: %s",
84 fileName, moreErrorStr);
85 errString = errBuf;
86 }
87 }
88 if (errString != NULL) {
89 PyErr_SetString(PyExc_ImportError, errString);
90 return NULL;
91 }
92 #ifdef USE_DYLD_GLOBAL_NAMESPACE
93 if (!NSIsSymbolNameDefined(funcname)) {
94 /* UnlinkModule() isn't implemented in current versions, but calling it does no harm */
95 /* NSUnLinkModule(newModule, FALSE); removed: causes problems for ObjC code */
96 PyErr_Format(PyExc_ImportError,
97 "Loaded module does not contain symbol %.200s",
98 funcname);
99 return NULL;
100 }
101 theSym = NSLookupAndBindSymbol(funcname);
102 #else
103 theSym = NSLookupSymbolInModule(newModule, funcname);
104 if ( theSym == NULL ) {
105 /* NSUnLinkModule(newModule, FALSE); removed: causes problems for ObjC code */
106 PyErr_Format(PyExc_ImportError,
107 "Loaded module does not contain symbol %.200s",
108 funcname);
109 return NULL;
110 }
111 #endif
112 p = (dl_funcptr)NSAddressOfSymbol(theSym);
113 return p;
114 }
115