work on making transformations use relative return values

[pspp] / src / language / control / do-if.c

diff --git a/src/language/control/do-if.c b/src/language/control/do-if.c
index ea7056709115da24c396d84114de751a982345d9..f5ebe799e34c0eb091513889d8123f3215431fa7 100644 (file)
--- a/src/language/control/do-if.c
+++ b/src/language/control/do-if.c
@@ -76,9 +76,17 @@ struct do_if_trns
     struct dataset *ds;         /* The dataset */
     struct clause *clauses;     /* Clauses. */
     size_t clause_cnt;          /* Number of clauses. */
+    int DO_IF_index;            /* DO IF transformation. */
     int past_END_IF_index;      /* Transformation just past last clause. */
   };
 
+/* Jumps past the END IF.  */
+struct end_if_trns
+  {
+    struct do_if_trns *do_if;
+    int index;
+  };
+
 static const struct ctl_class do_if_class;
 
 static int parse_clause (struct lexer *, struct do_if_trns *, struct dataset *ds);
@@ -89,8 +97,8 @@ static bool has_else (struct do_if_trns *);
 static bool must_not_have_else (struct do_if_trns *);
 static void close_do_if (void *do_if);
 
-static trns_proc_func do_if_trns_proc, break_trns_proc;
-static trns_free_func do_if_trns_free;
+static trns_proc_func do_if_trns_proc, end_if_trns_proc;
+static trns_free_func do_if_trns_free, end_if_trns_free;
 
 /* Parse DO IF. */
 int
@@ -100,6 +108,7 @@ cmd_do_if (struct lexer *lexer, struct dataset *ds)
   do_if->clauses = NULL;
   do_if->clause_cnt = 0;
   do_if->ds = ds;
+  do_if->DO_IF_index = next_transformation (ds);
 
   ctl_stack_push (&do_if_class, do_if);
   add_transformation (ds, do_if_trns_proc, do_if_trns_free, do_if);
@@ -214,7 +223,15 @@ add_clause (struct do_if_trns *do_if, struct expression *condition)
   struct clause *clause;
 
   if (do_if->clause_cnt > 0)
-    add_transformation (do_if->ds, break_trns_proc, NULL, do_if);
+    {
+      struct end_if_trns *end_if;
+
+      end_if = xmalloc (sizeof *end_if);
+      end_if->do_if = do_if;
+      end_if->index = next_transformation (do_if->ds);
+      add_transformation (do_if->ds,
+                          end_if_trns_proc, end_if_trns_free, end_if);
+    }
 
   do_if->clauses = xnrealloc (do_if->clauses,
                               do_if->clause_cnt + 1, sizeof *do_if->clauses);
@@ -239,12 +256,12 @@ do_if_trns_proc (void *do_if_, struct ccase **c, casenumber case_num UNUSED)
         {
           double boolean = expr_evaluate_num (clause->condition, *c, case_num);
           if (boolean == 1.0)
-            return clause->target_index;
+            return clause->target_index - do_if->DO_IF_index;
           else if (boolean == SYSMIS)
-            return do_if->past_END_IF_index;
+            return do_if->past_END_IF_index - do_if->DO_IF_index;
         }
       else
-        return clause->target_index;
+        return clause->target_index - do_if->DO_IF_index;
     }
   return do_if->past_END_IF_index;
 }
@@ -266,14 +283,23 @@ do_if_trns_free (void *do_if_)
 
 /* Breaks out of a DO IF construct. */
 static int
-break_trns_proc (void *do_if_, struct ccase **c UNUSED,
+end_if_trns_proc (void *end_if_, struct ccase **c UNUSED,
                  casenumber case_num UNUSED)
 {
-  struct do_if_trns *do_if = do_if_;
+  struct end_if_trns *end_if = end_if_;
 
-  return do_if->past_END_IF_index;
+  return end_if->do_if->past_END_IF_index - end_if->index;
 }
 
+/* Frees an END IF transformation. */
+static bool
+end_if_trns_free (void *end_if_)
+{
+  struct end_if_trns *end_if = end_if_;
+
+  free (end_if);
+  return true;
+}
 /* DO IF control structure class definition. */
 static const struct ctl_class do_if_class =
   {