[PATCH v2 06/11] efi_loader: move console-input helpers to efi_app_common

[Simon Glass]

Hi Heinrich,

On 2026-06-21T08:19:04, Heinrich Schuchardt
<heinrich.schuchardt at canonical.com> wrote:
> efi_loader: move console-input helpers to efi_app_common
>
> Move the shared console-input helpers to efi_app_common:
>
> * efi_drain_input() - drain the console input queue
> * efi_input_yn()    - read a y/n/ESC key from the user
> * efi_input()       - read a UTF-16 string from the console
>
> The common efi_input_yn() calls efi_drain_input() once at entry,
> replacing the open-coded cin->reset() calls that each application
> previously duplicated.
>
> dbginfodump and smbiosdump had no efi_drain_input() call in their
> command loops; add the call so the console queue is drained before
> each prompt, fixing a latent input-echo artefact.
>
> The common state is extended with a cin pointer (initialized by
> efi_app_init from sys_table->con_in) so the helpers can access the
> console-input protocol without additional parameters.
>
> [...]
>
> lib/efi_loader/dbginfodump.c    |  61 ----------------------
>  lib/efi_loader/dtbdump.c        | 109 ----------------------------------------
>  lib/efi_loader/efi_app_common.c |  88 ++++++++++++++++++++++++++++++++
>  lib/efi_loader/efi_app_common.h |  29 +++++++++++
>  lib/efi_loader/initrddump.c     | 109 ----------------------------------------
>  lib/efi_loader/smbiosdump.c     | 108 +--------------------------------------
>  6 files changed, 119 insertions(+), 385 deletions(-)

Reviewed-by: Simon Glass <sjg at chromium.org>

thoughts below

> diff --git a/lib/efi_loader/dbginfodump.c b/lib/efi_loader/dbginfodump.c
> @@ -277,7 +217,6 @@ efi_status_t EFIAPI efi_main(efi_handle_t image_handle,
>       handle = image_handle;
>       systable = systab;
>       cout = systable->con_out;
> -     cin = systable->con_in;
>       bs = systable->boottime;

The commit message says efi_drain_input() is added to dbginfodump and
smbiosdump command loops, but only smbiosdump's command_loop() gets it
- dbginfodump's efi_main() loop does not. On top of that, the old
dbginfodump efi_input() opened with cin->reset(cin, true); the new
common efi_input() does not drain at entry, so this patch silently
removes drain-on-input from dbginfodump. Please add efi_drain_input()
to dbginfodump's command loop too, or update the commit message.

> diff --git a/lib/efi_loader/efi_app_common.c b/lib/efi_loader/efi_app_common.c
> @@ -104,3 +106,89 @@ bool starts_with(u16 *string, u16 *keyword)
> +efi_status_t efi_input(u16 *buffer, efi_uintn_t buffer_size)
> +{
> +     struct efi_input_key key = { 0 };
> +     efi_uintn_t index;
> +     efi_uintn_t pos = 0;
> +     u16 outbuf[2] = u" ";
> +     efi_status_t ret;
> +
> +     *buffer = 0;

efi_input_yn() drains at entry but efi_input() does not - easy to trip
over later. Either drain inside efi_input() too (matching the old
dbginfodump/smbiosdump versions), or document in the header that
callers must drain themselves. What do you think?

Regards,
Simon