From e9550d0b383ffaacb83325343eb1952849951208 Mon Sep 17 00:00:00 2001
From: Sven Verdoolaege <skimo@kotnet.org>
Date: Fri, 16 Oct 2009 14:30:24 +0200
Subject: [PATCH] isl_tab: support generic undo records

---
 isl_tab.c | 9 +++++++++
 isl_tab.h | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/isl_tab.c b/isl_tab.c
index c09b6cb..0316a73 100644
--- a/isl_tab.c
+++ b/isl_tab.c
@@ -799,6 +799,13 @@ int isl_tab_push_basis(struct isl_tab *tab)
 	return push_union(tab, isl_tab_undo_saved_basis, u);
 }
 
+int isl_tab_push_callback(struct isl_tab *tab, struct isl_tab_callback *callback)
+{
+	union isl_tab_undo_val u;
+	u.callback = callback;
+	return push_union(tab, isl_tab_undo_callback, u);
+}
+
 struct isl_tab *isl_tab_init_samples(struct isl_tab *tab)
 {
 	if (!tab)
@@ -2755,6 +2762,8 @@ static int perform_undo(struct isl_tab *tab, struct isl_tab_undo *undo)
 	case isl_tab_undo_saved_samples:
 		drop_samples_since(tab, undo->u.n);
 		break;
+	case isl_tab_undo_callback:
+		return undo->u.callback->run(undo->u.callback);
 	default:
 		isl_assert(tab->mat->ctx, 0, return -1);
 	}
diff --git a/isl_tab.h b/isl_tab.h
index 5036273..13919cf 100644
--- a/isl_tab.h
+++ b/isl_tab.h
@@ -31,12 +31,18 @@ enum isl_tab_undo_type {
 	isl_tab_undo_saved_basis,
 	isl_tab_undo_drop_sample,
 	isl_tab_undo_saved_samples,
+	isl_tab_undo_callback,
+};
+
+struct isl_tab_callback {
+	int (*run)(struct isl_tab_callback *cb);
 };
 
 union isl_tab_undo_val {
 	int		var_index;
 	int		*col_var;
 	int		n;
+	struct isl_tab_callback	*callback;
 };
 
 struct isl_tab_undo {
@@ -237,4 +243,7 @@ int isl_tab_save_samples(struct isl_tab *tab) WARN_UNUSED;
 struct isl_tab *isl_tab_detect_equalities(struct isl_tab *tab,
 	struct isl_tab *tab_cone) WARN_UNUSED;
 
+int isl_tab_push_callback(struct isl_tab *tab,
+	struct isl_tab_callback *callback) WARN_UNUSED;
+
 #endif
-- 
2.7.4