1 files changed, 91 insertions, 0 deletions
diff --git a/src/list.h b/src/list.h
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+++ b/src/list.h
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+/*
+ * Copyright 2019-2021 OARC, Inc.
+ * Copyright 2017-2018 Akamai Technologies
+ * Copyright 2006-2016 Nominum, Inc.
+ * All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef PERF_LIST_H
+#define PERF_LIST_H 1
+
+#include <assert.h>
+
+#define perf_link(type)    \
+    struct {               \
+        type *prev, *next; \
+    } _link
+#define perf_link_init(link)    \
+    {                           \
+        (link)->_link.prev = 0; \
+        (link)->_link.next = 0; \
+    }
+
+#define perf_list(type)    \
+    struct {               \
+        type *head, *tail; \
+    }
+#define perf_list_init(list) \
+    {                        \
+        (list).head = 0;     \
+        (list).tail = 0;     \
+    }
+
+#define perf_list_head(list) ((list).head)
+#define perf_list_tail(list) ((list).tail)
+#define perf_list_empty(list) (!(list).head)
+
+#define perf_list_append(list, link)          \
+    {                                         \
+        if ((list).tail) {                    \
+            (list).tail->_link.next = (link); \
+        } else {                              \
+            (list).head = (link);             \
+        }                                     \
+        (link)->_link.prev = (list).tail;     \
+        (link)->_link.next = 0;               \
+        (list).tail        = (link);          \
+    }
+#define perf_list_prepend(list, link)         \
+    {                                         \
+        if ((list).head) {                    \
+            (list).head->_link.prev = (link); \
+        } else {                              \
+            (list).tail = (link);             \
+        }                                     \
+        (link)->_link.prev = 0;               \
+        (link)->_link.next = (list).head;     \
+        (list).head        = (link);          \
+    }
+#define perf_list_unlink(list, link)                             \
+    {                                                            \
+        if ((link)->_link.next) {                                \
+            (link)->_link.next->_link.prev = (link)->_link.prev; \
+        } else {                                                 \
+            assert((list).tail == (link));                       \
+            (list).tail = (link)->_link.prev;                    \
+        }                                                        \
+        if ((link)->_link.prev) {                                \
+            (link)->_link.prev->_link.next = (link)->_link.next; \
+        } else {                                                 \
+            assert((list).head == (link));                       \
+            (list).head = (link)->_link.next;                    \
+        }                                                        \
+        (link)->_link.next = 0;                                  \
+        (link)->_link.prev = 0;                                  \
+        assert((list).head != (link));                           \
+        assert((list).tail != (link));                           \
+    }
+
+#endif