mountd: move most of get_exportlist() into helpers

I needed to understand get_exportlist() recently, and it gave me
trouble.

Move detail work into helper functions to make the basic logic clear,
and to remove need for excessive nesting (and fix inconsistent
indentation levels).  Also remove unnecessary casts of void returns from
xmalloc().

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

diff --git a/utils/mountd/mountd.c b/utils/mountd/mountd.c
index 179ef17aa53ca76375d7ff775d92c3d31b926217..ecd7c35cd66e43b0ea2b9634bc6c841c7028a537 100644 (file)
--- a/utils/mountd/mountd.c
+++ b/utils/mountd/mountd.c
@@ -509,12 +509,89 @@ get_rootfh(struct svc_req *rqstp, dirpath *path, nfs_export **expret,
        return fh;
 }
 
+static void remove_all_clients(exportnode *e)
+{
+       struct groupnode *g, *ng;
+
+       for (g = e->ex_groups; g; g = ng) {
+               ng = g->gr_next;
+               xfree(g->gr_name);
+               xfree(g);
+       }
+       e->ex_groups = NULL;
+}
+
+static void free_exportlist(exports *elist)
+{
+       struct exportnode *e, *ne;
+
+       for (e = *elist; e != NULL; e = ne) {
+               ne = e->ex_next;
+               remove_all_clients(e);
+               xfree(e->ex_dir);
+               xfree(e);
+       }
+       *elist = NULL;
+}
+
+static void prune_clients(nfs_export *exp, struct exportnode *e)
+{
+       struct hostent  *hp;
+       struct groupnode *c, **cp;
+
+       cp = &e->ex_groups;
+       while ((c = *cp) != NULL) {
+               if (client_gettype(c->gr_name) == MCL_FQDN
+                               && (hp = gethostbyname(c->gr_name))) {
+                       hp = hostent_dup(hp);
+                       if (client_check(exp->m_client, hp)) {
+                               *cp = c->gr_next;
+                               xfree(c->gr_name);
+                               xfree(c);
+                               xfree (hp);
+                               continue;
+                       }
+                       xfree (hp);
+               }
+               cp = &(c->gr_next);
+       }
+}
+
+static exportnode *lookup_or_create_elist_entry(exports *elist, nfs_export *exp)
+{
+       exportnode *e;
+
+       for (e = *elist; e != NULL; e = e->ex_next) {
+               if (!strcmp(exp->m_export.e_path, e->ex_dir))
+                       return e;
+       }
+       e = xmalloc(sizeof(*e));
+       e->ex_next = *elist;
+       e->ex_groups = NULL;
+       e->ex_dir = xstrdup(exp->m_export.e_path);
+       *elist = e;
+       return e;
+}
+
+static void insert_group(struct exportnode *e, char *newname)
+{
+       struct groupnode *g;
+
+       for (g = e->ex_groups; g; g = g->gr_next)
+               if (strcmp(g->gr_name, newname))
+                       return;
+
+       g = xmalloc(sizeof(*g));
+       g->gr_name = xstrdup(newname);
+       g->gr_next = e->ex_groups;
+       e->ex_groups = g;
+}
+
 static exports
 get_exportlist(void)
 {
        static exports          elist = NULL;
-       struct exportnode       *e, *ne;
-       struct groupnode        *g, *ng, *c, **cp;
+       struct exportnode       *e;
        nfs_export              *exp;
        int                     i;
        static unsigned int     ecounter;
@@ -526,80 +603,28 @@ get_exportlist(void)
 
        ecounter = acounter;
 
-       for (e = elist; e != NULL; e = ne) {
-               ne = e->ex_next;
-               for (g = e->ex_groups; g != NULL; g = ng) {
-                       ng = g->gr_next;
-                       xfree(g->gr_name);
-                       xfree(g);
-               }
-               xfree(e->ex_dir);
-               xfree(e);
-       }
-       elist = NULL;
+       free_exportlist(&elist);
 
        for (i = 0; i < MCL_MAXTYPES; i++) {
                for (exp = exportlist[i].p_head; exp; exp = exp->m_next) {
                         /* Don't show pseudo exports */
                        if (exp->m_export.e_flags & NFSEXP_V4ROOT)
                                continue;
-
-                       for (e = elist; e != NULL; e = e->ex_next) {
-                               if (!strcmp(exp->m_export.e_path, e->ex_dir))
-                                       break;
-                       }
-                       if (!e) {
-                               e = (struct exportnode *) xmalloc(sizeof(*e));
-                               e->ex_next = elist;
-                               e->ex_groups = NULL;
-                               e->ex_dir = xstrdup(exp->m_export.e_path);
-                               elist = e;
-                       }
+                       e = lookup_or_create_elist_entry(&elist, exp);
 
                        /* We need to check if we should remove
                           previous ones. */
                        if (i == MCL_ANONYMOUS && e->ex_groups) {
-                               for (g = e->ex_groups; g; g = ng) {
-                                       ng = g->gr_next;
-                                       xfree(g->gr_name);
-                                       xfree(g);
-                               }
-                               e->ex_groups = NULL;
+                               remove_all_clients(e);
                                continue;
                        }
 
                        if (i != MCL_FQDN && e->ex_groups) {
-                         struct hostent        *hp;
-
-                         cp = &e->ex_groups;
-                         while ((c = *cp) != NULL) {
-                           if (client_gettype (c->gr_name) == MCL_FQDN
-                               && (hp = gethostbyname(c->gr_name))) {
-                             hp = hostent_dup (hp);
-                             if (client_check(exp->m_client, hp)) {
-                               *cp = c->gr_next;
-                               xfree(c->gr_name);
-                               xfree(c);
-                               xfree (hp);
-                               continue;
-                             }
-                             xfree (hp);
-                           }
-                           cp = &(c->gr_next);
-                         }
+                               prune_clients(exp, e);
                        }
 
                        if (exp->m_export.e_hostname [0] != '\0') {
-                               for (g = e->ex_groups; g; g = g->gr_next)
-                                       if (strcmp (exp->m_export.e_hostname,
-                                                   g->gr_name) == 0)
-                                               break;
-                               if (g)
-                                       continue;
-                               g = (struct groupnode *) xmalloc(sizeof(*g));
-                               g->gr_name = xstrdup(exp->m_export.e_hostname);
-                               g->gr_next = e->ex_groups;
-                               e->ex_groups = g;
+                               insert_group(e, exp->m_export.e_hostname);
                        }
                }
        }