Renamed, and bug fixed:

Two interesting problems in nis_maplist().  First, it is possible that
clnt_create() will return NULL.  This was being caught, but no Python
error was being set.  I use clnt_spcreateerror() to generate the value
of the exception.

But why would clnt_create() fail?  It's because no server was being
found.  And why was this?  It was because nis_maplist() tried only to
get the NIS master for the first map in the aliases list, which is
passwd.byname, and guess what?  That's the one NIS map CNRI does *not*
export!  So the yp_master() call was failing to return a valid
server.  I now cycle through all the map aliases until I find a valid
master.  If not, a different exception is set.

I'm not sure this is the completely correct way to do all this, but
short of rewriting the entire nismodule.c (to expose the proper API to
Python), it should do the trick.

Modules/nismodule.c

@@ -10,9 +10,7 @@
 
 /* NIS module implementation */
 
-#include "allobjects.h"
-#include "modsupport.h"
-#include "ceval.h"
+#include "Python.h"
 
 #include <sys/time.h>
 #include <sys/types.h>
@@ -25,13 +23,13 @@
 extern int yp_get_default_domain();
 #endif
 
-static object *NisError;
+static PyObject *NisError;
 
-static object *
+static PyObject *
 nis_error (err)
 	int err;
 {
-	err_setstr(NisError, yperr_string(err));
+	PyErr_SetString(NisError, yperr_string(err));
 	return NULL;
 }
 
@@ -62,7 +60,7 @@ nis_mapname (map)
 	return map;
 }
 
-typedef int (*foreachfunc) PROTO((int, char *, int, char *, int, char *));
+typedef int (*foreachfunc) Py_PROTO((int, char *, int, char *, int, char *));
 
 static int
 nis_foreach (instatus, inkey, inkeylen, inval, invallen, indata)
@@ -71,24 +69,24 @@ nis_foreach (instatus, inkey, inkeylen, inval, invallen, indata)
 	int inkeylen;
 	char *inval;
 	int invallen;
-	object *indata;
+	PyObject *indata;
 {
 	if (instatus == YP_TRUE) {
-		object *key = newsizedstringobject(inkey, inkeylen);
-		object *val = newsizedstringobject(inval, invallen);
+		PyObject *key = PyString_FromStringAndSize(inkey, inkeylen);
+		PyObject *val = PyString_FromStringAndSize(inval, invallen);
 		int err;
 		if (key == NULL || val == NULL) {
 			/* XXX error -- don't know how to handle */
-			err_clear();
-			XDECREF(key);
-			XDECREF(val);
+			PyErr_Clear();
+			Py_XDECREF(key);
+			Py_XDECREF(val);
 			return 1;
 		}
-		err = mappinginsert(indata, key, val);
-		DECREF(key);
-		DECREF(val);
+		err = PyDict_SetItem(indata, key, val);
+		Py_DECREF(key);
+		Py_DECREF(val);
 		if (err != 0) {
-			err_clear();
+			PyErr_Clear();
 			return 1;
 		}
 		return 0;
@@ -96,59 +94,59 @@ nis_foreach (instatus, inkey, inkeylen, inval, invallen, indata)
 	return 1;
 }
 
-static object *
+static PyObject *
 nis_match (self, args)
-	object *self;
-	object *args;
+	PyObject *self;
+	PyObject *args;
 {
 	char *match;
 	char *domain;
 	int keylen, len;
 	char *key, *map;
 	int err;
-	object *res;
+	PyObject *res;
 
-	if (!getargs(args, "(s#s)", &key, &keylen, &map))
+	if (!PyArg_Parse(args, "(s#s)", &key, &keylen, &map))
 		return NULL;
 	if ((err = yp_get_default_domain(&domain)) != 0)
 		return nis_error(err);
-	BGN_SAVE
+	Py_BEGIN_ALLOW_THREADS
 	map = nis_mapname (map);
 	err = yp_match (domain, map, key, keylen, &match, &len);
-	END_SAVE
+	Py_END_ALLOW_THREADS
 	if (err != 0)
 		return nis_error(err);
-	res = newsizedstringobject (match, len);
+	res = PyString_FromStringAndSize (match, len);
 	free (match);
 	return res;
 }
 
-static object *
+static PyObject *
 nis_cat (self, args)
-	object *self;
-	object *args;
+	PyObject *self;
+	PyObject *args;
 {
 	char *domain;
 	char *map;
 	struct ypall_callback cb;
-	object *cat;
+	PyObject *cat;
 	int err;
 
-	if (!getstrarg(args, &map))
+	if (!PyArg_Parse(args, "s", &map))
 		return NULL;
 	if ((err = yp_get_default_domain(&domain)) != 0)
 		return nis_error(err);
-	cat = newdictobject ();
+	cat = PyDict_New ();
 	if (cat == NULL)
 		return NULL;
 	cb.foreach = (foreachfunc)nis_foreach;
 	cb.data = (char *)cat;
-	BGN_SAVE
+	Py_BEGIN_ALLOW_THREADS
 	map = nis_mapname (map);
 	err = yp_all (domain, map, &cb);
-	END_SAVE
+	Py_END_ALLOW_THREADS
 	if (err != 0) {
-		DECREF(cat);
+		Py_DECREF(cat);
 		return nis_error(err);
 	}
 	return cat;
@@ -170,23 +168,23 @@ typedef char *domainname;
 typedef char *mapname;
 
 enum nisstat {
-    NIS_TRUE = 1,
-    NIS_NOMORE = 2,
-    NIS_FALSE = 0,
-    NIS_NOMAP = -1,
-    NIS_NODOM = -2,
-    NIS_NOKEY = -3,
-    NIS_BADOP = -4,
-    NIS_BADDB = -5,
-    NIS_YPERR = -6,
-    NIS_BADARGS = -7,
-    NIS_VERS = -8
+	NIS_TRUE = 1,
+	NIS_NOMORE = 2,
+	NIS_FALSE = 0,
+	NIS_NOMAP = -1,
+	NIS_NODOM = -2,
+	NIS_NOKEY = -3,
+	NIS_BADOP = -4,
+	NIS_BADDB = -5,
+	NIS_YPERR = -6,
+	NIS_BADARGS = -7,
+	NIS_VERS = -8
 };
 typedef enum nisstat nisstat;
 
 struct nismaplist {
-    mapname map;
-    struct nismaplist *next;
+	mapname map;
+	struct nismaplist *next;
 };
 typedef struct nismaplist nismaplist;
 
@@ -201,86 +199,90 @@ static struct timeval TIMEOUT = { 25, 0 };
 static
 bool_t
 nis_xdr_domainname(xdrs, objp)
-    XDR *xdrs;
-    domainname *objp;
+	XDR *xdrs;
+	domainname *objp;
 {
-    if (!xdr_string(xdrs, objp, YPMAXDOMAIN)) {
-        return (FALSE);
-    }
-    return (TRUE);
+	if (!xdr_string(xdrs, objp, YPMAXDOMAIN)) {
+		return (FALSE);
+	}
+	return (TRUE);
 }
 
 static
 bool_t
 nis_xdr_mapname(xdrs, objp)
-    XDR *xdrs;
-    mapname *objp;
+	XDR *xdrs;
+	mapname *objp;
 {
-    if (!xdr_string(xdrs, objp, YPMAXMAP)) {
-        return (FALSE);
-    }
-    return (TRUE);
+	if (!xdr_string(xdrs, objp, YPMAXMAP)) {
+		return (FALSE);
+	}
+	return (TRUE);
 }
 
 static
 bool_t
 nis_xdr_ypmaplist(xdrs, objp)
-    XDR *xdrs;
-    nismaplist *objp;
+	XDR *xdrs;
+	nismaplist *objp;
 {
-    if (!nis_xdr_mapname(xdrs, &objp->map)) {
-        return (FALSE);
-    }
-    if (!xdr_pointer(xdrs, (char **)&objp->next, sizeof(nismaplist), nis_xdr_ypmaplist)) {
-        return (FALSE);
-    }
-    return (TRUE);
+	if (!nis_xdr_mapname(xdrs, &objp->map)) {
+		return (FALSE);
+	}
+	if (!xdr_pointer(xdrs, (char **)&objp->next,
+			 sizeof(nismaplist), nis_xdr_ypmaplist))
+	{
+		return (FALSE);
+	}
+	return (TRUE);
 }
 
 static
 bool_t
 nis_xdr_ypstat(xdrs, objp)
-    XDR *xdrs;
-    nisstat *objp;
+	XDR *xdrs;
+	nisstat *objp;
 {
-    if (!xdr_enum(xdrs, (enum_t *)objp)) {
-        return (FALSE);
-    }
-    return (TRUE);
+	if (!xdr_enum(xdrs, (enum_t *)objp)) {
+		return (FALSE);
+	}
+	return (TRUE);
 }
 
 
 static
 bool_t
 nis_xdr_ypresp_maplist(xdrs, objp)
-    XDR *xdrs;
-    nisresp_maplist *objp;
+	XDR *xdrs;
+	nisresp_maplist *objp;
 {
-    if (!nis_xdr_ypstat(xdrs, &objp->stat)) {
-        return (FALSE);
-    }
-    if (!xdr_pointer(xdrs, (char **)&objp->maps, sizeof(nismaplist), nis_xdr_ypmaplist)) {
-        return (FALSE);
-    }
-    return (TRUE);
+	if (!nis_xdr_ypstat(xdrs, &objp->stat)) {
+		return (FALSE);
+	}
+	if (!xdr_pointer(xdrs, (char **)&objp->maps,
+			 sizeof(nismaplist), nis_xdr_ypmaplist))
+	{
+		return (FALSE);
+	}
+	return (TRUE);
 }
 
 
 static
 nisresp_maplist *
 nisproc_maplist_2(argp, clnt)
-    domainname *argp;
-    CLIENT *clnt;
+	domainname *argp;
+	CLIENT *clnt;
 {
-    static nisresp_maplist res;
-
-    memset(&res, 0, sizeof(res));
-    if (clnt_call(clnt, YPPROC_MAPLIST, nis_xdr_domainname, (caddr_t)argp,
-		  nis_xdr_ypresp_maplist, (caddr_t)&res, TIMEOUT)
-	!= RPC_SUCCESS) {
-        return (NULL);
-    }
-    return (&res);
+	static nisresp_maplist res;
+
+	memset(&res, 0, sizeof(res));
+	if (clnt_call(clnt, YPPROC_MAPLIST, nis_xdr_domainname, (caddr_t)argp,
+		      nis_xdr_ypresp_maplist, (caddr_t)&res, TIMEOUT)
+	    != RPC_SUCCESS) {
+		return (NULL);
+	}
+	return (&res);
 }
 
 static
@@ -290,13 +292,21 @@ nis_maplist ()
 	nisresp_maplist *list;
 	char *dom;
 	CLIENT *cl, *clnt_create();
-	char *server;
+	char *server = "";
+	int mapi = 0;
 
 	yp_get_default_domain (&dom);
-	yp_master (dom, aliases[0].map, &server);
+	while (!strcmp("", server) && aliases[mapi].map != 0L) {
+		yp_master (dom, aliases[mapi].map, &server);
+		mapi++;
+	}
+        if (!strcmp("", server)) {
+            PyErr_SetString(NisError, "No NIS master found for any map");
+            return NULL;
+        }
 	cl = clnt_create(server, YPPROG, YPVERS, "tcp");
 	if (cl == NULL) {
-		clnt_pcreateerror(server);
+		PyErr_SetString(NisError, clnt_spcreateerror(server));
 		return NULL;
 	}
 	list = nisproc_maplist_2 (&dom, cl);
@@ -307,21 +317,22 @@ nis_maplist ()
 	return list->maps;
 }
 
-static object *
+static PyObject *
 nis_maps (self, args)
-	object *self;
-	object *args;
+	PyObject *self;
+	PyObject *args;
 {
 	nismaplist *maps;
-	object *list;
+	PyObject *list;
 
 	if ((maps = nis_maplist ()) == NULL)
 		return NULL;
-	if ((list = newlistobject(0)) == NULL)
+	if ((list = PyList_New(0)) == NULL)
 		return NULL;
 	for (maps = maps->next; maps; maps = maps->next) {
-		if (addlistitem (list, newstringobject (maps->map)) < 0) {
-			DECREF(list);
+		if (PyList_Append (list, PyString_FromString (maps->map)) < 0)
+		{
+			Py_DECREF(list);
 			list = NULL;
 			break;
 		}
@@ -330,7 +341,7 @@ nis_maps (self, args)
 	return list;
 }
 
-static struct methodlist nis_methods[] = {
+static PyMethodDef nis_methods[] = {
 	{"match",	nis_match},
 	{"cat",		nis_cat},
 	{"maps",	nis_maps},
@@ -340,10 +351,11 @@ static struct methodlist nis_methods[] = {
 void
 initnis ()
 {
-	object *m, *d;
-	m = initmodule("nis", nis_methods);
-	d = getmoduledict(m);
-	NisError = newstringobject("nis.error");
-	if (NisError == NULL || dictinsert(d, "error", NisError) != 0)
-		fatal("Cannot define nis.error");
+	PyObject *m, *d;
+	m = Py_InitModule("nis", nis_methods);
+	d = PyModule_GetDict(m);
+	NisError = PyString_FromString("nis.error");
+	if (NisError == NULL ||
+	    PyDict_SetItemString(d, "error", NisError) != 0)
+		Py_FatalError("Cannot define nis.error");
 }