isl_basic_set_opt: avoid invalid access on error path

[platform/upstream/isl.git] / isl_list_templ.c

diff --git a/isl_list_templ.c b/isl_list_templ.c
index ec5391b..0af5b76 100644 (file)
--- a/isl_list_templ.c
+++ b/isl_list_templ.c
@@ -1,13 +1,15 @@
 /*
  * Copyright 2008-2009 Katholieke Universiteit Leuven
  * Copyright 2011      INRIA Saclay
+ * Copyright 2012      Ecole Normale Superieure
  *
- * Use of this software is governed by the GNU LGPLv2.1 license
+ * Use of this software is governed by the MIT license
  *
  * Written by Sven Verdoolaege, K.U.Leuven, Departement
  * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
  * and INRIA Saclay - Ile-de-France, Parc Club Orsay Universite,
  * ZAC des vignes, 4 rue Jacques Monod, 91893 Orsay, France
+ * and Ecole Normale Superieure, 45 rue d’Ulm, 75230 Paris, France
  */
 
 #define xCAT(A,B) A ## B
@@ -159,6 +161,50 @@ __isl_give LIST(EL) *FN(LIST(EL),drop)(__isl_take LIST(EL) *list,
        return list;
 }
 
+/* Insert "el" at position "pos" in "list".
+ *
+ * If there is only one reference to "list" and if it already has space
+ * for one extra element, we insert it directly into "list".
+ * Otherwise, we create a new list consisting of "el" and copied
+ * elements from "list".
+ */
+__isl_give LIST(EL) *FN(LIST(EL),insert)(__isl_take LIST(EL) *list,
+       unsigned pos, __isl_take struct EL *el)
+{
+       int i;
+       isl_ctx *ctx;
+       LIST(EL) *res;
+
+       if (!list || !el)
+               goto error;
+       ctx = FN(LIST(EL),get_ctx)(list);
+       if (pos > list->n)
+               isl_die(ctx, isl_error_invalid,
+                       "index out of bounds", goto error);
+
+       if (list->ref == 1 && list->size > list->n) {
+               for (i = list->n - 1; i >= pos; --i)
+                       list->p[i + 1] = list->p[i];
+               list->n++;
+               list->p[pos] = el;
+               return list;
+       }
+
+       res = FN(LIST(EL),alloc)(ctx, list->n + 1);
+       for (i = 0; i < pos; ++i)
+               res = FN(LIST(EL),add)(res, FN(EL,copy)(list->p[i]));
+       res = FN(LIST(EL),add)(res, el);
+       for (i = pos; i < list->n; ++i)
+               res = FN(LIST(EL),add)(res, FN(EL,copy)(list->p[i]));
+       FN(LIST(EL),free)(list);
+
+       return res;
+error:
+       FN(EL,free)(el);
+       FN(LIST(EL),free)(list);
+       return NULL;
+}
+
 void *FN(LIST(EL),free)(__isl_take LIST(EL) *list)
 {
        int i;