[Zope] - ZMySQLDA/MySQLmodule.c: Bugs and fixes

[Mitch Chapman]

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This really concerns MySQLmodule.c, not ZMySQLDA per se.
But I found these problems while working w. Zope, so thought
it best to address the Zope list too.

Problem 1:
	When compiling against MySQL 3.22.14b-gamma, this warning is
	displayed:
	./MySQLmodule.c: In function `pythonify_row':
	./MySQLmodule.c:199: warning: assignment from incompatible pointer type
Cause:
	mysql_fetch_lengths() returns 'unsigned long *'.  The
	result is being assigned to   'unsigned int *'.  Not a problem
        on many 32-bit platforms, but what the hey.

Problem 2:
	When attempting to do an invalid database insert
	(e.g. inserting with a duplicate key value), Python dumps
	core.
Cause:
	In function DBH_query(), not all fields of sth are properly
	initialized.  When a database insert fails, sth->res has a
	random value.  The subsequent free(self->res) in STH_dealloc()
	generates a bus error.

The attached context diff contains the fixes I used.
Lemme know if you have any questions/corrections.
-- 
Mitch Chapman			  |	4105 Executive Drive
Ohio Electronic Engravers, Inc.	  |	Beavercreek, OH  45430
mchapman@oee.com		  |	import StandardDisclaimer
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*** MySQLmodule.c	Tue Dec 22 12:34:23 1998
--- MySQLmodule.c.patched	Fri Jan 22 18:33:43 1999
***************
*** 193,199 ****
      PyObject *rowlist, *fieldobj;
      MYSQL_FIELD *tf;
      int i, n;
!     unsigned int *lengths;
  
      n = mysql_num_fields(res);
      lengths = mysql_fetch_lengths(res);
--- 193,199 ----
      PyObject *rowlist, *fieldobj;
      MYSQL_FIELD *tf;
      int i, n;
!     unsigned long *lengths;
  
      n = mysql_num_fields(res);
      lengths = mysql_fetch_lengths(res);
***************
*** 902,907 ****
--- 902,908 ----
      if (sth == NULL) return NULL;
      sth->sth_use_result = self->dbh_use_result;
      sth->dbh = NULL;
+     sth->res = NULL;
      if (!PyArg_ParseTuple(args, "s#|i:query", &query, &size, &(sth->sth_use_result))) {
          Py_XDECREF(sth);
  	return NULL;

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