第 7 章：压缩列表

压缩列表的各个部分

digraph { label = "\n 图 7-1 压缩列表的各个组成部分"; node [shape = record]; ziplist [label = " zlbytes | zltail | zllen | entry1 | entry2 | ... | entryN | zlend "]; }

一个包含三个节点的压缩列表示例。

digraph { rankdir = BT; label = "\n 图 7-2 包含三个节点的压缩列表"; node [shape = record]; ziplist [label = " <zlbytes> zlbytes \n 0x50 | zltail \n 0x3c | zllen \n 0x3 | entry1 | entry2 | <entry3> entry3 | zlend \n 0xFF "]; node [shape = plaintext]; p [label = "p"]; p -> ziplist:zlbytes; tail [label = "p + 60"]; tail -> ziplist:entry3; }

一个包含五个节点的压缩列表示例。

digraph { label = "\n 图 7-3 包含五个节点的压缩列表"; rankdir = BT; node [shape = record]; ziplist [label = " <zlbytes> zlbytes \n 0xd2 | zltail \n 0xb3 | zllen \n 0x5 | entry1 | entry2 | entry3 | entry4 | <entry5> entry5 | zlend \n 0xFF "]; node [shape = plaintext]; p [label = "p"]; p -> ziplist:zlbytes; tail [label = "p + 179"]; tail -> ziplist:entry5; }

压缩列表节点的各个组成部分。

digraph { label = "\n 图 7-4 压缩列表节点的各个组成部分"; node [shape = record]; n [label = " previous_entry_length | encoding | content "]; }

压缩列表节点的 previous_entry_length 属性示例。

digraph { label = "\n 图 7-5 当前节点的前一节点的长度为 5 字节"; node [shape = record]; n [label = " previous_entry_length \n 0x05 | encoding \n ... | content \n ... "]; }

使用压缩列表节点的 previous_entry_length 属性遍历整个压缩列表的过程。

digraph { rankdir = BT; node [shape = record]; entry1 [label = " zlbytes | zltail | zllen | <e1> entry1 | <e2> entry2 | <e3> entry3 | <e4> entry4 | zlend "]; node [shape = plaintext]; p1 -> entry1:e4; }
digraph { rankdir = BT; node [shape = record]; entry2 [label = " zlbytes | zltail | zllen | <e1> entry1 | <e2> entry2 | <e3> entry3 | <e4> entry4 | zlend "]; node [shape = plaintext]; p2 [label = "p2 = p1 - entry4.previous_entry_length"]; p2 -> entry2:e3; }
digraph { rankdir = BT; node [shape = record]; entry3 [label = " zlbytes | zltail | zllen | <e1> entry1 | <e2> entry2 | <e3> entry3 | <e4> entry4 | zlend "]; node [shape = plaintext]; p3 [label = "p3 = p2 - entry3.previous_entry_length"]; p3 -> entry3:e2; }
digraph { label = "\n 图 7-8 一个从表尾向表头遍历的例子"; rankdir = BT; node [shape = record]; entry4 [label = " zlbytes | zltail | zllen | <e1> entry1 | <e2> entry2 | <e3> entry3 | <e4> entry4 | zlend "]; node [shape = plaintext]; p4 [label = "p4 = p3 - entry2.previous_entry_length"]; p4 -> entry4:e1; }

一个保存着 "hello world" 字符串的压缩列表节点示例。

digraph { label = "\n 图 7-9 保存着字节数组 \"hello world\" 的节点"; node [shape = record]; entry [label = " previous_entry_length \n ... | encoding \n 00001011 | content \n \"hello world\" "]; }

一个保存着整数 10086 的压缩列表节点示例。

digraph { label = "\n 图 7-10 保存着整数值 10086 的节点"; node [shape = record]; entry [label = " previous_entry_length \n ... | encoding \n 11000000 | content \n 10086 "]; }

向压缩列表添加新节点并引发连锁更新的过程。

digraph { label = "\n 图 7-11 包含节点 e1 至 eN 的压缩列表"; node [shape = record]; ziplist [label = " zlbytes| zltail | zllen | e1 | e2 | e3 | ... | eN | zlend "]; }
digraph { label = "\n 图 7-12 添加新节点到压缩列表"; rankdir = BT; node [shape = record]; ziplist [label = " zlbytes | zltail | zllen | <new> new | e1 | e2 | e3 | ... | eN | zlend "]; p [label = "添加新节点", shape = plaintext]; p -> ziplist:new; }
digraph { rankdir = BT; node [shape = record]; ziplist [label = " zlbytes | zltail | zllen | <new> new | <e1> e1 | <e2> e2 | <e3> e3 | ... | <en> eN | zlend "]; p [label = "扩展 e1 \n并引发对 e2 的扩展", shape = plaintext]; p -> ziplist:e1; }
digraph { rankdir = BT; node [shape = record]; ziplist [label = " zlbytes | zltail | zllen | <new> new | <e1> e1 | <e2> e2 | <e3> e3 | ... | <en> eN | zlend "]; p [label = "扩展 e2 \n并引发对 e3 的扩展", shape = plaintext]; p -> ziplist:e2; }
digraph { rankdir = BT; node [shape = record]; ziplist [label = " zlbytes | zltail | zllen | <new> new | <e1> e1 | <e2> e2 | <e3> e3 | ... | <en> eN | zlend "]; p [label = "扩展 e3 \n并引发对 e4 的扩展", shape = plaintext]; p -> ziplist:e3; }
digraph { rankdir = BT; node [shape = record]; ziplist [label = " zlbytes | zltail | zllen | <new> new | <e1> e1 | <e2> e2 | <e3> e3 | <more> ... | <en> eN | zlend "]; p [label = "一直扩展下去……", shape = plaintext]; p -> ziplist:more; }
digraph { label = "\n 图 7-13 连锁更新过程"; rankdir = BT; node [shape = record]; ziplist [label = " zlbytes | zltail | zllen | <new> new | <e1> e1 | <e2> e2 | <e3> e3 | <e4> e4 | ... | <eN> eN | zlend "]; p [label = "为 eN-1 扩展 eN 的 previous_entry_length 属性 \n 连锁更新到此结束", shape = plaintext]; p -> ziplist:eN; }