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authorEric Blake <eblake@redhat.com>2016-05-31 10:41:28 -0600
committerMarkus Armbruster <armbru@redhat.com>2016-06-30 15:28:40 +0200
commitfec0fc0a13ac7f1a1130433a6740cd850c3db34a (patch)
treef5dcc1ae871f41e227c411c00ba52aa9e6394d66 /util/range.c
parent9b4e38fe6a35890bb1d995316d7be08de0b30ee5 (diff)
range: Create range.c for code that should not be inline
g_list_insert_sorted_merged() is rather large to be an inline function; move it to its own file. range_merge() and ranges_can_merge() can likewise move, as they are only used internally. Also, it becomes obvious that the condition within range_merge() is already satisfied by its caller, and that the return value is not used. The diffstat is misleading, because of the copyright boilerplate. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1464712890-14262-2-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
Diffstat (limited to 'util/range.c')
-rw-r--r--util/range.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/util/range.c b/util/range.c
new file mode 100644
index 0000000000..f775f2e673
--- /dev/null
+++ b/util/range.c
@@ -0,0 +1,81 @@
+/*
+ * QEMU 64-bit address ranges
+ *
+ * Copyright (c) 2015-2016 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/range.h"
+
+/*
+ * Operations on 64 bit address ranges.
+ * Notes:
+ * - ranges must not wrap around 0, but can include the last byte ~0x0LL.
+ * - this can not represent a full 0 to ~0x0LL range.
+ */
+
+/* 0,1 can merge with 1,2 but don't overlap */
+static bool ranges_can_merge(Range *range1, Range *range2)
+{
+ return !(range1->end < range2->begin || range2->end < range1->begin);
+}
+
+static void range_merge(Range *range1, Range *range2)
+{
+ if (range1->end < range2->end) {
+ range1->end = range2->end;
+ }
+ if (range1->begin > range2->begin) {
+ range1->begin = range2->begin;
+ }
+}
+
+GList *g_list_insert_sorted_merged(GList *list, gpointer data,
+ GCompareFunc func)
+{
+ GList *l, *next = NULL;
+ Range *r, *nextr;
+
+ if (!list) {
+ list = g_list_insert_sorted(list, data, func);
+ return list;
+ }
+
+ nextr = data;
+ l = list;
+ while (l && l != next && nextr) {
+ r = l->data;
+ if (ranges_can_merge(r, nextr)) {
+ range_merge(r, nextr);
+ l = g_list_remove_link(l, next);
+ next = g_list_next(l);
+ if (next) {
+ nextr = next->data;
+ } else {
+ nextr = NULL;
+ }
+ } else {
+ l = g_list_next(l);
+ }
+ }
+
+ if (!l) {
+ list = g_list_insert_sorted(list, data, func);
+ }
+
+ return list;
+}