Re: [PATCH v3 03/25] bootmenu: Add a few comments

[Heinrich Schuchardt <xypron.glpk@gmx.de>]

On 1/6/23 15:52, Simon Glass wrote:
> The behaviour of these two functions is completely undocumented. Add some
> notes so the poor, suffering dev can figure out what is going on.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
> (no changes since v1)
>
>   include/menu.h | 42 ++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 42 insertions(+)
>
> diff --git a/include/menu.h b/include/menu.h
> index 702aacb170c..0b4d9734149 100644
> --- a/include/menu.h
> +++ b/include/menu.h
> @@ -42,6 +42,7 @@ struct bootmenu_data {
>   	struct bootmenu_entry *first;	/* first menu entry */
>   };
>
> +/** enum bootmenu_key - keys that can be returned by the bootmenu */
>   enum bootmenu_key {
>   	KEY_NONE = 0,
>   	KEY_UP,
> @@ -53,8 +54,49 @@ enum bootmenu_key {
>   	KEY_SPACE,
>   };
>
> +/**
> + * bootmenu_autoboot_loop() - handle autobooting if no key is pressed
> + *
> + * This shows a prompt to allow the user to press a key to interrupt auto boot
> + * of the first menu option.
> + *
> + * It then waits for the required time (menu->delay in seconds) for a key to be
> + * pressed. If nothing is pressed in that time, @key returns KEY_SELECT
> + * indicating that the current option should be chosen.
> + *
> + * @menu: Menu being processed
> + * @key: Returns the code for the key the user pressed:
> + *	enter: KEY_SELECT
> + *	Ctrl-C: KEY_QUIT
> + *	anything else: KEY_NONE
> + * @esc: Set to 1 if the escape key is pressed, otherwise not updated
> + */
>   void bootmenu_autoboot_loop(struct bootmenu_data *menu,
>   			    enum bootmenu_key *key, int *esc);
> +
> +/**
> + * bootmenu_loop() - handle waiting for a keypress when autoboot is disabled
> + *
> + * This is used when the menu delay is negative, indicating that the delay has
> + * elapsed, or there was no delay to begin with.
> + *
> + * It reads a character and processes it, returning a menu-key code if a
> + * character is recognised
> + *
> + * @menu: Menu being processed
> + * @key: Returns the code for the key the user pressed:
> + *	enter: KEY_SELECT
> + *	Ctrl-C: KEY_QUIT
> + *	Up arrow: KEY_UP
> + *	Down arrow: KEY_DOWN
> + *	Escape (by itself): KEY_QUIT
> + *	Plus: KEY_PLUS
> + *	Minus: KEY_MINUS
> + *	Space: KEY_SPACE
> + * @esc: On input, a non-zero value indicates that an escape sequence has
> + *	resulted in that many characters so far. On exit this is updated to the
> + *	new number of characters
> + */
>   void bootmenu_loop(struct bootmenu_data *menu,
>   		   enum bootmenu_key *key, int *esc);

This should not be an exported function. The program part that wants to
display a menu should not have to deal with navigation keys.

Best regards

Heinrich