| /* Support for dynamic loading of extension modules */ | |
| #include "Python.h" | |
| #ifdef HAVE_DIRECT_H | |
| #include <direct.h> | |
| #endif | |
| #include <ctype.h> | |
| #include "importdl.h" | |
| #include <windows.h> | |
| // "activation context" magic - see dl_nt.c... | |
| extern ULONG_PTR _Py_ActivateActCtx(); | |
| void _Py_DeactivateActCtx(ULONG_PTR cookie); | |
| const struct filedescr _PyImport_DynLoadFiletab[] = { | |
| #ifdef _DEBUG | |
| {"_d.pyd", "rb", C_EXTENSION}, | |
| #else | |
| {".pyd", "rb", C_EXTENSION}, | |
| #endif | |
| {0, 0} | |
| }; | |
| /* Case insensitive string compare, to avoid any dependencies on particular | |
| C RTL implementations */ | |
| static int strcasecmp (char *string1, char *string2) | |
| { | |
| int first, second; | |
| do { | |
| first = tolower(*string1); | |
| second = tolower(*string2); | |
| string1++; | |
| string2++; | |
| } while (first && first == second); | |
| return (first - second); | |
| } | |
| /* Function to return the name of the "python" DLL that the supplied module | |
| directly imports. Looks through the list of imported modules and | |
| returns the first entry that starts with "python" (case sensitive) and | |
| is followed by nothing but numbers until the separator (period). | |
| Returns a pointer to the import name, or NULL if no matching name was | |
| located. | |
| This function parses through the PE header for the module as loaded in | |
| memory by the system loader. The PE header is accessed as documented by | |
| Microsoft in the MSDN PE and COFF specification (2/99), and handles | |
| both PE32 and PE32+. It only worries about the direct import table and | |
| not the delay load import table since it's unlikely an extension is | |
| going to be delay loading Python (after all, it's already loaded). | |
| If any magic values are not found (e.g., the PE header or optional | |
| header magic), then this function simply returns NULL. */ | |
| #define DWORD_AT(mem) (*(DWORD *)(mem)) | |
| #define WORD_AT(mem) (*(WORD *)(mem)) | |
| static char *GetPythonImport (HINSTANCE hModule) | |
| { | |
| unsigned char *dllbase, *import_data, *import_name; | |
| DWORD pe_offset, opt_offset; | |
| WORD opt_magic; | |
| int num_dict_off, import_off; | |
| /* Safety check input */ | |
| if (hModule == NULL) { | |
| return NULL; | |
| } | |
| /* Module instance is also the base load address. First portion of | |
| memory is the MS-DOS loader, which holds the offset to the PE | |
| header (from the load base) at 0x3C */ | |
| dllbase = (unsigned char *)hModule; | |
| pe_offset = DWORD_AT(dllbase + 0x3C); | |
| /* The PE signature must be "PE\0\0" */ | |
| if (memcmp(dllbase+pe_offset,"PE\0\0",4)) { | |
| return NULL; | |
| } | |
| /* Following the PE signature is the standard COFF header (20 | |
| bytes) and then the optional header. The optional header starts | |
| with a magic value of 0x10B for PE32 or 0x20B for PE32+ (PE32+ | |
| uses 64-bits for some fields). It might also be 0x107 for a ROM | |
| image, but we don't process that here. | |
| The optional header ends with a data dictionary that directly | |
| points to certain types of data, among them the import entries | |
| (in the second table entry). Based on the header type, we | |
| determine offsets for the data dictionary count and the entry | |
| within the dictionary pointing to the imports. */ | |
| opt_offset = pe_offset + 4 + 20; | |
| opt_magic = WORD_AT(dllbase+opt_offset); | |
| if (opt_magic == 0x10B) { | |
| /* PE32 */ | |
| num_dict_off = 92; | |
| import_off = 104; | |
| } else if (opt_magic == 0x20B) { | |
| /* PE32+ */ | |
| num_dict_off = 108; | |
| import_off = 120; | |
| } else { | |
| /* Unsupported */ | |
| return NULL; | |
| } | |
| /* Now if an import table exists, offset to it and walk the list of | |
| imports. The import table is an array (ending when an entry has | |
| empty values) of structures (20 bytes each), which contains (at | |
| offset 12) a relative address (to the module base) at which a | |
| string constant holding the import name is located. */ | |
| if (DWORD_AT(dllbase + opt_offset + num_dict_off) >= 2) { | |
| /* We have at least 2 tables - the import table is the second | |
| one. But still it may be that the table size is zero */ | |
| if (0 == DWORD_AT(dllbase + opt_offset + import_off + sizeof(DWORD))) | |
| return NULL; | |
| import_data = dllbase + DWORD_AT(dllbase + | |
| opt_offset + | |
| import_off); | |
| while (DWORD_AT(import_data)) { | |
| import_name = dllbase + DWORD_AT(import_data+12); | |
| if (strlen(import_name) >= 6 && | |
| !strncmp(import_name,"python",6)) { | |
| char *pch; | |
| /* Ensure python prefix is followed only | |
| by numbers to the end of the basename */ | |
| pch = import_name + 6; | |
| #ifdef _DEBUG | |
| while (*pch && pch[0] != '_' && pch[1] != 'd' && pch[2] != '.') { | |
| #else | |
| while (*pch && *pch != '.') { | |
| #endif | |
| if (*pch >= '0' && *pch <= '9') { | |
| pch++; | |
| } else { | |
| pch = NULL; | |
| break; | |
| } | |
| } | |
| if (pch) { | |
| /* Found it - return the name */ | |
| return import_name; | |
| } | |
| } | |
| import_data += 20; | |
| } | |
| } | |
| return NULL; | |
| } | |
| dl_funcptr _PyImport_GetDynLoadFunc(const char *fqname, const char *shortname, | |
| const char *pathname, FILE *fp) | |
| { | |
| dl_funcptr p; | |
| char funcname[258], *import_python; | |
| PyOS_snprintf(funcname, sizeof(funcname), "init%.200s", shortname); | |
| { | |
| HINSTANCE hDLL = NULL; | |
| char pathbuf[260]; | |
| LPTSTR dummy; | |
| unsigned int old_mode; | |
| ULONG_PTR cookie = 0; | |
| /* We use LoadLibraryEx so Windows looks for dependent DLLs | |
| in directory of pathname first. However, Windows95 | |
| can sometimes not work correctly unless the absolute | |
| path is used. If GetFullPathName() fails, the LoadLibrary | |
| will certainly fail too, so use its error code */ | |
| /* Don't display a message box when Python can't load a DLL */ | |
| old_mode = SetErrorMode(SEM_FAILCRITICALERRORS); | |
| if (GetFullPathName(pathname, | |
| sizeof(pathbuf), | |
| pathbuf, | |
| &dummy)) { | |
| ULONG_PTR cookie = _Py_ActivateActCtx(); | |
| /* XXX This call doesn't exist in Windows CE */ | |
| hDLL = LoadLibraryEx(pathname, NULL, | |
| LOAD_WITH_ALTERED_SEARCH_PATH); | |
| _Py_DeactivateActCtx(cookie); | |
| } | |
| /* restore old error mode settings */ | |
| SetErrorMode(old_mode); | |
| if (hDLL==NULL){ | |
| char errBuf[256]; | |
| unsigned int errorCode; | |
| /* Get an error string from Win32 error code */ | |
| char theInfo[256]; /* Pointer to error text | |
| from system */ | |
| int theLength; /* Length of error text */ | |
| errorCode = GetLastError(); | |
| theLength = FormatMessage( | |
| FORMAT_MESSAGE_FROM_SYSTEM | | |
| FORMAT_MESSAGE_IGNORE_INSERTS, /* flags */ | |
| NULL, /* message source */ | |
| errorCode, /* the message (error) ID */ | |
| 0, /* default language environment */ | |
| (LPTSTR) theInfo, /* the buffer */ | |
| sizeof(theInfo), /* the buffer size */ | |
| NULL); /* no additional format args. */ | |
| /* Problem: could not get the error message. | |
| This should not happen if called correctly. */ | |
| if (theLength == 0) { | |
| PyOS_snprintf(errBuf, sizeof(errBuf), | |
| "DLL load failed with error code %d", | |
| errorCode); | |
| } else { | |
| size_t len; | |
| /* For some reason a \r\n | |
| is appended to the text */ | |
| if (theLength >= 2 && | |
| theInfo[theLength-2] == '\r' && | |
| theInfo[theLength-1] == '\n') { | |
| theLength -= 2; | |
| theInfo[theLength] = '\0'; | |
| } | |
| strcpy(errBuf, "DLL load failed: "); | |
| len = strlen(errBuf); | |
| strncpy(errBuf+len, theInfo, | |
| sizeof(errBuf)-len); | |
| errBuf[sizeof(errBuf)-1] = '\0'; | |
| } | |
| PyErr_SetString(PyExc_ImportError, errBuf); | |
| return NULL; | |
| } else { | |
| char buffer[256]; | |
| #ifdef _DEBUG | |
| PyOS_snprintf(buffer, sizeof(buffer), "python%d%d_d.dll", | |
| #else | |
| PyOS_snprintf(buffer, sizeof(buffer), "python%d%d.dll", | |
| #endif | |
| PY_MAJOR_VERSION,PY_MINOR_VERSION); | |
| import_python = GetPythonImport(hDLL); | |
| if (import_python && | |
| strcasecmp(buffer,import_python)) { | |
| PyOS_snprintf(buffer, sizeof(buffer), | |
| "Module use of %.150s conflicts " | |
| "with this version of Python.", | |
| import_python); | |
| PyErr_SetString(PyExc_ImportError,buffer); | |
| FreeLibrary(hDLL); | |
| return NULL; | |
| } | |
| } | |
| p = GetProcAddress(hDLL, funcname); | |
| } | |
| return p; | |
| } |