1 files changed, 133 insertions, 0 deletions
diff --git a/libbanshee/engine/term-var.c b/libbanshee/engine/term-var.c
new file mode 100644
index 00000000000..9b8e2059871
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+++ b/libbanshee/engine/term-var.c
@@ -0,0 +1,133 @@
+/*
+ * Copyright (c) 2000-2001
+ *      The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+#include <stdio.h>
+#include <regions.h>
+#include <assert.h>
+#include "ufind.h"
+#include "term-var.h"
+
+DECLARE_UFIND(tv_elt,gen_e)
+ 
+DEFINE_UFIND(tv_elt,gen_e)
+
+DEFINE_LIST(term_var_list,term_var)
+
+struct term_var
+{
+#ifdef NONSPEC
+  sort_kind sort;
+#endif
+  int type;
+  stamp st;
+  gen_e_list pending;
+  const char *name;
+  tv_elt elt;
+};
+
+static term_var make_var(region r, const char *name, stamp st)
+{
+  term_var result = ralloc(r, struct term_var);
+  gen_e info = (gen_e) result;
+
+  result->type = VAR_TYPE;
+  result->st = st;
+  result->pending = new_gen_e_list(r);
+  result->name = name ? rstrdup(r,name) : "fv";
+  result->elt = new_tv_elt(r,info);
+
+  return result;
+}
+
+term_var tv_fresh(region r, const char *name)
+{
+  return make_var(r,name,stamp_fresh());
+}
+
+term_var tv_fresh_small(region r, const char *name)
+{
+  return make_var(r,name,stamp_fresh_small());
+}
+
+term_var tv_fresh_large(region r, const char *name)
+{
+  return make_var(r,name,stamp_fresh_large());
+}
+
+static term_var tv_get_v_ecr(term_var v)
+{
+  term_var ecr = (term_var)tv_get_ecr(v);
+  assert (ecr->type == VAR_TYPE); /* this is a hack, but should be ok */
+
+  return ecr;
+}
+
+const char *tv_get_name(term_var v)
+{
+  return tv_get_v_ecr(v)->name;
+}
+
+gen_e_list tv_get_pending(term_var v)
+{
+  return tv_get_v_ecr(v)->pending;
+}
+
+void tv_add_pending(term_var v,gen_e e)
+{
+  gen_e_list_cons(e,tv_get_v_ecr(v)->pending);
+}
+
+void tv_unify(term_var v, gen_e e)
+{
+  tv_elt_update(v->elt,e);
+  
+  assert(tv_get_ecr(v) == e);
+}
+
+static gen_e tv_combine(gen_e e1, gen_e e2)
+{
+  term_var v1 = (term_var)e1,
+    v2 = (term_var)e2;
+  
+  if (! (v1 == v2) )
+    gen_e_list_append(tv_get_pending(v1), tv_get_pending(v2));
+  
+  return e1;
+}
+
+void tv_unify_vars(term_var v1, term_var v2)
+{
+  tv_elt_unify(tv_combine,v1->elt, v2->elt);
+}
+
+gen_e tv_get_ecr(term_var v)
+{
+  return tv_elt_get_info(v->elt);
+}