Fix bug 1845

diff --git a/contrib/prune/prune.c b/contrib/prune/prune.c
index c9cc16a162d8375ed3a7495a239a644fa77d11e4..2fa0b1aa5b875dcdf62156833f635071dd996624 100644 (file)
--- a/contrib/prune/prune.c
+++ b/contrib/prune/prune.c
@@ -42,7 +42,7 @@ typedef struct strattr_s {
     char *v;
 } strattr_t;
 
-void remove_child(Agraph_t * graph, Agnode_t * node);
+int remove_child(Agraph_t * graph, Agnode_t * node);
 void help_message(const char *progname);
 
 generic_list_t *addattr(generic_list_t * l, char *a);
@@ -179,8 +179,8 @@ int main(int argc, char **argv)
                        if (verbose == 1)
                            fprintf(stderr, "Processing descendant: %s\n",
                                    agnameof(aghead(edge)));
-                       remove_child(graph, aghead(edge));
-                       agdelete(graph, edge);
+                       if (!remove_child(graph, aghead(edge)))
+                           agdelete(graph, edge);
                    }
                }
                UNMARK(node);   /* Unmark so that it can be removed in later passes */
@@ -209,21 +209,21 @@ int main(int argc, char **argv)
     exit(EXIT_SUCCESS);
 }
 
-void remove_child(Agraph_t * graph, Agnode_t * node)
+int remove_child(Agraph_t * graph, Agnode_t * node)
 {
     Agedge_t *edge;
     Agedge_t *nexte;
 
     /* Avoid cycles */
     if MARKED
-       (node) return;
+       (node) return 0;
     MARK(node);
 
     /* Skip nodes with more than one parent */
     edge = agfstin(graph, node);
     if (edge && (agnxtin(graph, edge) != NULL)) {
        UNMARK(node);
-       return;
+       return 0;
     }
 
     /* recursively remove children */
@@ -233,13 +233,13 @@ void remove_child(Agraph_t * graph, Agnode_t * node)
            if (verbose)
                fprintf(stderr, "Processing descendant: %s\n",
                        agnameof(aghead(edge)));
-           remove_child(graph, aghead(edge));
-           agdeledge(graph, edge);
+           if (!remove_child(graph, aghead(edge)))
+               agdeledge(graph, edge);
        }
     }
 
     agdelnode(graph, node);
-    return;
+    return 1;
 }
 
 void help_message(const char *progname)