vgetargskeywords:

+ Generally test nkeywords against 0 instead of keywords against NULL
  (saves a little work if an empty keywords dict is passed, and is
  conceptually more on-target regardless).
+ When a call erroneously specifies a keyword argument both by position
  and by keyword name:
    - It was easy to provoke this routine into an internal buffer overrun
      by using a long argument name.  Now uses PyErr_format instead (which
      computes a safe buffer size).
    - Improved the error msg.

diff --git a/Python/getargs.c b/Python/getargs.c
index dd80fd107884ce81238f7ea3443e28ec5dbe1df0..9796b5e8393a4c0246c72104c96cbd09dfe330b4 100644 (file)
--- a/Python/getargs.c
+++ b/Python/getargs.c
@@ -1085,16 +1085,16 @@ vgetargskeywords(PyObject *args, PyObject *keywords, char *format,
        /* make sure there are no duplicate values for an argument;
           its not clear when to use the term "keyword argument vs. 
           keyword parameter in messages */
-       if (keywords) {
+       if (nkeywords > 0) {
                for (i = 0; i < nargs; i++) {
                        char *thiskw = kwlist[i];
                        if (thiskw == NULL)
                                break;
                        if (PyMapping_HasKeyString(keywords, thiskw)) {
-                               sprintf(msgbuf,
-                                       "keyword parameter %s redefined",
+                               PyErr_Format(PyExc_TypeError,
+                                       "keyword parameter '%s' was given "
+                                       "by position and by name",
                                        thiskw);
-                               PyErr_SetString(PyExc_TypeError, msgbuf);
                                return 0;
                        }
                }
@@ -1155,29 +1155,23 @@ vgetargskeywords(PyObject *args, PyObject *keywords, char *format,
        }
 
        /* handle no keyword parameters in call  */     
-                  
-       if (!keywords)
+       if (nkeywords == 0)
                return 1; 
-               
+
        /* make sure the number of keywords in the keyword list matches the 
           number of items in the format string */
-         
        nkwlist = 0;
        p =  kwlist;
-       for (;;) {
-               if (!*(p++)) break;
+       while (*p++)
                nkwlist++;
-       }
-
        if (nkwlist != max) {
                PyErr_SetString(PyExc_SystemError,
          "number of items in format string and keyword list do not match");
                return 0;
        }                 
-                       
+               
        /* convert the keyword arguments; this uses the format 
           string where it was left after processing args */
-       
        converted = 0;
        for (i = nargs; i < nkwlist; i++) {
                PyObject *item;
@@ -1202,9 +1196,8 @@ vgetargskeywords(PyObject *args, PyObject *keywords, char *format,
                        }
                }
        }
-       
+
        /* make sure there are no extraneous keyword arguments */
-       
        pos = 0;
        if (converted < nkeywords) {
                while (PyDict_Next(keywords, &pos, &key, &value)) {