refactor(os/input.c): rename os_inchar => input_get #30327

Problem:
The name `os_inchar` (from Vim's old `mch_inchar`) is ambiguous:
"inchar" sounds like it could be reading or enqueuing (setting) input.
Its docstring is also ambiguous.

Solution:
- Rename `os_inchar` to `input_get`.
- Write some mf'ing docstrings.
- Add assert() in TRY_READ().

1 files changed, 3 insertions, 4 deletions

diff --git a/src/nvim/state.c b/src/nvim/state.c
index eab976927c..1b08a08fba 100644
--- a/src/nvim/state.c
+++ b/src/nvim/state.c
@@ -74,10 +74,9 @@ getkey:
       }
       // Flush screen updates before blocking.
       ui_flush();
-      // Call `os_inchar` directly to block for events or user input without
-      // consuming anything from `input_buffer`(os/input.c) or calling the
-      // mapping engine.
-      os_inchar(NULL, 0, -1, typebuf.tb_change_cnt, main_loop.events);
+      // Call `input_get` directly to block for events or user input without consuming anything from
+      // `os/input.c:input_buffer` or calling the mapping engine.
+      input_get(NULL, 0, -1, typebuf.tb_change_cnt, main_loop.events);
       // If an event was put into the queue, we send K_EVENT directly.
       if (!input_available() && !multiqueue_empty(main_loop.events)) {
         key = K_EVENT;