chore(docs): update func and span docs

docs/book/cn/func.md

@@ -2,6 +2,12 @@
 
 
 
+### 视频介绍
+
+<iframe src="//player.bilibili.com/player.html?bvid=BV1vT4y1t7ha&page=1&autoplay=0" scrolling="no" border="0" frameborder="no" framespacing="0" allowfullscreen="true" height="480px" width="100%"> </iframe>
+
+
+
 ### 头文件
 
 ```c

docs/book/cn/span.md

@@ -10,6 +10,12 @@ Melon中的资源开销（span）组件是用来测量C语言函数开销的，
 
 
 
+### 视频介绍
+
+<iframe src="//player.bilibili.com/player.html?bvid=BV1jZ4y1E7H9&page=1&autoplay=0" scrolling="no" border="0" frameborder="no" framespacing="0" allowfullscreen="true" height="480px" width="100%"> </iframe>
+
+
+
 ### 头文件
 
 ```c
@@ -131,6 +137,54 @@ void mln_span_free(mln_span_t *s);
 
 
 
+#### mln_span_file
+
+```c
+mln_span_file(s);
+```
+
+描述：获取指定span所在文件的文件名。
+
+返回值：`char *`文件名指针
+
+
+
+#### mln_span_func
+
+```c
+mln_span_func(s);
+```
+
+描述：获取指定span所针对的函数名。
+
+返回值：`char *`函数名指针
+
+
+
+#### mln_span_line
+
+```c
+mln_span_line(s);
+```
+
+描述：获取指定span所针对的文件行数。
+
+返回值：`int`类型文件行数
+
+
+
+#### mln_span_time_cost
+
+```c
+mln_span_time_cost(s);
+```
+
+描述：获取指定span所测量的耗时时长，以微秒为单位。
+
+返回值：`mln_u64_t`微秒数
+
+
+
 ### 示例
 
 这是一个多线程的示例，用来展示`mln_span`接口的使用以及在多线程环境下的效果。

docs/book/en/span.md

@@ -130,6 +130,54 @@ Return value: None
 
 
 
+#### mln_span_file
+
+```c
+mln_span_file(s);
+```
+
+Description: Get the filename of the specified span's location.
+
+Return value: `char *` pointer to the filename.
+
+
+
+#### mln_span_func
+
+```c
+mln_span_func(s);
+```
+
+Description: Get the function name referred to by the specified span.
+
+Return value: `char *` pointer to the function name.
+
+
+
+#### mln_span_line
+
+```c
+mln_span_line(s);
+```
+
+Description: Get the line number of the file referred to by the specified span.
+
+Return value: `int` representing the line number.
+
+
+
+#### mln_span_time_cost
+
+```c
+mln_span_time_cost(s);
+```
+
+Description: Get the duration of the measurement taken by the specified span, in microseconds.
+
+Return value: `mln_u64_t` representing the duration in microseconds.
+
+
+
 ### Example
 
 This is a multi-threading example demonstrating the usage of the `mln_span` interfaces and its runtime behavior in a multi-threaded environment.