msgid "" msgstr "" "Project-Id-Version: Chinese (Simplified Han script) (Boost Beast Translation " "(zh_Hans))\n" "Report-Msgid-Bugs-To: \n" "POT-Creation-Date: 2026-07-25 16:44+0000\n" "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n" "Last-Translator: FULL NAME \n" "Language-Team: Chinese (Simplified Han script) \n" "Language: zh_Hans\n" "MIME-Version: 1.0\n" "Content-Type: text/plain; charset=UTF-8\n" "Content-Transfer-Encoding: 8bit\n" "Plural-Forms: nplurals=1; plural=0;\n" "X-Generator: Weblate 2026.5\n" #. type: section title #: 10 msgid "Detect SSL __example__" msgstr "检测 SSL __示例__" #. type: paragraph #: 12 msgid "" "In this example we will build a simple function to detect the presence of " "the [@https://tools.ietf.org/html/rfc2246#section-7.4 TLS client handshake] " "given an input buffer sequence. Then we build on the example by adding a " "synchronous stream algorithm. Finally, we implement an asynchronous " "detection function using a composed operation. This SSL detector may be used " "to allow a server to accept both TLS and plain (unencrypted) connections at " "the same port." msgstr "" "本示例将构建一个简单函数，用于检测输入缓冲区序列中是否存在 TLS 客户端握手协议" "。然后在该示例的基础上，添加一个同步流算法。最后，通过组合操作实现异步检测函" "数。该 SSL 检测器可用于让服务器在同一端口上同时接受 TLS 和明文（未加密）连接" "。" #. type: paragraph #: 20 msgid "" "Here is the declaration for a function template to detect the SSL client " "handshake. The function accepts any object whose type meets the requirements " "of __ConstBufferSequence__. This gives callers flexibility to use a buffer " "object whose behavior is appropriate to the task." msgstr "" "以下函数模板声明用于检测 SSL 客户端握手。该函数接受任何满足 " "__ConstBufferSequence__ 概念要求的对象，从而使调用方能够根据任务需要灵活选择" "合适的缓冲区对象。" #. type: paragraph #: 27 msgid "" "The algorithm examines the buffer starting from the beginning, and performs " "a series of qualifying checks against the TLS specification. When not enough " "data exists to be certain, the returned value of `boost::indeterminate` " "informs the caller to read more data into the buffer. The function " "definition for the declaration above follows:" msgstr "" "该算法从缓冲区开头开始检查，并按照 TLS 规范进行一系列验证。如果数据不足，无法" "确定结果，则返回 `boost::indeterminate`，通知调用方继续向缓冲区读入更多数据。" "上面声明的函数，其定义如下：" #. type: paragraph #: 35 msgid "" "The detection function above is suitably generic and targeted in focus that " "it may be used as a building block to create higher level abstractions. Our " "goal is to create a ['stream algorithm]: a function which is invoked with a " "stream, that reads or writes (or both) to achieve a purpose. In this case, " "to detect the TLS client handshake. Stream algorithms may be synchronous or " "asynchronous. Because synchronous algorithms are easier to write, we start " "there. Then we build the asynchronous version, trying to model it similarly " "to make reasoning about it easier." msgstr "" "上述检测函数足够通用，且目标明确，可以作为基础模块来构建更高级的抽象。接下来" "要创建一个流算法：该算法接收一个流作为参数，通过执行读写操作来达到特定目的，" "这里就是检测 TLS 客户端握手。流算法可以是同步的，也可以是异步的。同步算法更容" "易编写，因此先实现同步版本，再在此基础上构建异步版本，并尽量让两者风格相似，" "便于理解。" #. type: paragraph #: 44 msgid "The synchronous version is implemented thusly:" msgstr "同步版本的实现如下：" #. type: paragraph #: 48 msgid "" "Now that we have the synchronous version, we can attempt to model the " "asynchronous version similarly. A function which launches an asynchronous " "operation is called an ['initiating function]. While the synchronous " "version above produces an error code through an output parameter, the " "asynchronous version delivers the error code to a completion handler or " "other custom mechanism defined by the completion token. The signature of the " "initiating function reflects these differences." msgstr "" "有了同步版本之后，可以尝试以类似方式构建异步版本。启动异步操作的函数称为发起" "函数。上述同步版本通过输出参数返回错误码，而异步版本则通过完成处理器或由完成" "令牌定义的其他自定义机制来传递错误码。发起函数的签名反映了这些差异。" #. type: paragraph #: 56 msgid "" "First we declare the initiating function and document the requirements, " "parameters, preconditions, and effects:" msgstr "首先声明发起函数，并说明其使用要求、参数、前置条件及功能效果：" #. type: paragraph #: 61 msgid "" "There are two additional components required to implement the initiating " "function:" msgstr "实现发起函数还需要以下两个额外组件：" #. type: list #: 64 msgid "* An intermediate completion handler, called the \"composed operation\"" msgstr "* 一个中间完成处理器，称为“组合操作”" #. type: list #: 69 msgid "* An \"initiation\" function object which when invoked with parameters" msgstr "* 一个“发起”函数对象，当使用参数调用时" #. type: paragraph #: 73 msgid "" "Here we forward declare the composed operation type, and provide the " "definition of the initiation function object. They are placed in the " "`detail` namespace since they should not be public:" msgstr "" "这里先对组合操作类型进行前置声明，然后给出发起函数对象的定义。因为这些组件属" "于内部实现细节，不对外公开，所以都放在 `detail` 命名空间中：" #. type: paragraph #: 79 msgid "" "The initiating function definition itself is straightforward. We perform " "type checking on the parameters, and then let `net::async_initiate` capture " "the parameter list along with a copy of our initiation function object. " "Depending on the specialization of `async_result` for the type of " "`CompletionToken`, the initiation function may be invoked immediately. " "Alternatively, it may be invoked later, after the initiating function " "returns. This is known as \"lazy execution,\" and allows efficient and " "expressive abstractions to be written." msgstr "" "发起函数的定义本身并不复杂：先对参数进行类型检查，再通过 " "`net::async_initiate` 捕获参数列表和发起函数对象的一个副本。根据 " "`CompletionToken` 类型对应的 `async_result` 特化版本，发起函数可以立即执行，" "也可以在发起函数返回之后再执行。后者称为“延迟执行”，这种机制便于编写高效且表" "达力强的抽象。" #. type: paragraph #: 90 msgid "" "Now we will declare our composed operation. There is a considerable amount " "of necessary boilerplate to get this right, but the result is worth the " "effort." msgstr "接下来声明组合操作。虽然需要编写不少必要的样板代码，但最终效果是值得的。" #. type: paragraph #: 96 msgid "" "The boilerplate is all done, and now we need to implement the function call " "operator that turns this composed operation a completion handler with the " "signature `void(error_code, std::size_t)` which is exactly the signature " "needed when performing asynchronous reads. This function is a transformation " "of the synchronous version of `detect_ssl` above, but with the inversion of " "flow that characterizes code written in the callback style:" msgstr "" "样板代码已经全部完成，接下来需要实现函数调用运算符，使该组合操作成为一个具有 " "`void(error_code, std::size_t)` 签名的完成处理器，而这正是执行异步读取时所需" "的签名。该函数是对上述同步版本 `detect_ssl` 的一种转换，但与同步版本不同，它" "采用了回调风格代码特有的控制流反转方式：" #. type: paragraph #: 106 msgid "" "The examples [path_link example/advanced/server/advanced_server.cpp advanced-" "server] and [path_link example/advanced/server-flex/advanced_server_flex.cpp " "advanced-server-flex] use this SSL detection function." msgstr "" "示例 [path_link example/advanced/server/advanced_server.cpp advanced-server] " "和 [path_link example/advanced/server-flex/advanced_server_flex.cpp advanced-" "server-flex] 使用了该 SSL 检测函数。"