NT specific change for nicer error message (Mark H)

diff --git a/Python/importdl.c b/Python/importdl.c
index 16b50aff0cea8ee26020fdc0551b721deea8fb35..65f2f72ff6beae9cb35031e542b10c8c85d418c3 100644 (file)
--- 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;
                }