diff --git a/Python/importdl.c b/Python/importdl.c index 16b50aff0ce..65f2f72ff6b 100644 --- a/Python/importdl.c +++ b/Python/importdl.c @@ -336,9 +336,38 @@ load_dynamic_module(name, pathname, fp) HINSTANCE hDLL; hDLL = LoadLibrary(pathname); if (hDLL==NULL){ - char errBuf[64]; - sprintf(errBuf, "DLL load failed with error code %d", - GetLastError()); + 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, /* 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) { + sprintf(errBuf, "DLL load failed with error code %d", errorCode); + } else { + int 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'; + } err_setstr(ImportError, errBuf); return NULL; }