[libc-commits] [libc] [libc] add doc for search.h (PR #80492)

[Schrodinger ZHU Yifan via libc-commits]

================
@@ -0,0 +1,85 @@
+=============
+Search Tables
+=============
+
+.. include:: check.rst
+
+---------------
+Source location
+---------------
+
+-   The main source for bitwise utility functions is located at:
+    ``libc/src/search``.
+
+-   Hashtable implementation is located at:
+    ``libc/src/__support/HashTable``.
+
+-   The tests are located at:
+    ``libc/test/src/search/``.
+
+---------------------
+Implementation Status
+---------------------
+
+POSIX Standard Types
+====================
+
+============================ =========
+Type Name                    Available
+============================ =========
+ACTION                       |check|
+ENTRY                        |check|
+VISIT                        
+============================ =========
+
+
+GNU Extension Types
+===================
+
+============================ ================= =========
+Type Name                    Associated Macro  Available
+============================ ================= ========= 
+struct qelem                 
+__compar_fn_t                __COMPAR_FN_T
+comparison_fn_t
+__action_fn_t                __ACTION_FN_T
+__free_fn_t
----------------
SchrodingerZhu wrote:

 `qelem` is for `insque` and `remque`. It is the suggested struct header. The remaining is for the binary tree operations. GNU just gives them a name. Notice that `__compar_fn_t` is the same for `qsort`, that's why it has a macro guard.

https://github.com/llvm/llvm-project/pull/80492