The formatting with %pa / %pap behaves like %x, which results in an
incorrect value being output. To improve this, a new fine-tuning
Kconfig SPL_USE_TINY_PRINTF_POINTER_SUPPORT for pointer formatting
has been added. If it is enabled, the output of %pa / %pap should
be correct, and if it is disabled, the pointer formatting is
completely unsupported. In addition to indicate unsupported formatting,
'?' will be output. This allows enabling pointer formatting only
when needed. For SPL_NET it is selected by default. Then it also
supports the formatting with %pm, %pM and %pI4.

In summery this level of %p support for tiny printf is possible now:

1) The standard tiny printf won't have support for pointer formatting.
   So it doesn't print misleading values for %pa, instead '?' will be
   output:
   %p   => ?
   %pa  => ?a
   %pap => ?ap

2) If SPL_USE_TINY_PRINTF_POINTER_SUPPORT is enabled or DEBUG is defined
   tiny printf supports formatting %p and %pa / %pap.

3) If SPL_NET is enabled the support of pointers is extended
   for %pm, %pM and %pI4.

Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>

Andre Przywara <andre.przywara@arm.com> says:

C's implicit fallthrough behaviour in switch/case statements can lead to
subtle bugs. Quite some while ago many compilers introduced warnings in
those cases, requiring intentional fallthrough's to be annotated.

So far we were not enabling that compiler option, so many ambiguities
and some bugs in the code went unnoticed.

This series adds the required annotations in code paths that the first
stage of the U-Boot CI covers. There is a large number of cases left
in the libbz2 code. The usage of switch/case is borderline insane there,
labels are hidden in macros, and there are no breaks, but just goto's.
Upstream still uses very similar code, without any annotations. I still
am not 100% sure those are meant to fall through or not, and plan to do
further investigations, but didn't want to hold the rest of the patches
back. You can see for yourself by applying patch 18/18 and building for
sandbox64, for instance.

Because of this we cannot quite enable the warning in the Makefile yet,
but those fixes are worth regardless, and be it to increase readability.

Please note that those patches do not fix anything, really, they just add
those fallthrough annotations, so the series is not really critical.

Link: https://lore.kernel.org/r/20250327153313.2105227-1-andre.przywara@arm.com

In some cases in the generic code, we were already using switch/case
fallthrough annotations comments, though in a way which might not be
understood by most compilers.

Replace two non-standard /* no break */ comments with our fallthrough;
statement-like macro, to make this visible to the compiler.
Also use this macro in place of an /* Fall through */ comment, to be
more consistent.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

If tiny printf is used with 0x%08X (upper case X) the output is
always 0x00000000. It could be confusing if upper case instead
of lower case is used intentionally or accidentally because the
actual value is not output. To avoid this confusion, treat output
of %X as %x. As a compromise for tiny printf, the hex value is
then output correctly, but in lower case. This is done to keep it
tiny printf small.

Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Marek Vasut <marex@denx.de>

The current code has a problematic corner case with formar "%c" and
0 as parameter. The proper zero byte is being emitted into digit buffer
but the final copy into outstr expects null-terminated string and doesn't
copy the required \0 byte. This has lead to malformed TFTP packets, refer
to tftp_send() which relies on %c to generate multiple zero-terminated
strings in one buffer.

Introduce a variable to force the copy of one character in this case.
The new behaviour is consistent with non-tiny implementation.

Reported-by: Chintan Vankar <c-vankar@ti.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>

A NULL pointer argument to %s causes a NULL pointer dereference in the
fixed width numerical printout code, since p is overwritten with NULL.
In case of %s width is 0. Check width before dereferencing the pointer.

Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
Reviewed-by: John Ogness <john.ogness@linutronix.de>

Add what it takes to enable NETDEVICES with NET_LWIP and enable DHCP as
well as the dhcp command. CMD_TFTPBOOT is selected by BOOTMETH_EFI due
to this code having an implicit dependency on do_tftpb().

Note that PXE is likely non-fonctional with NET_LWIP (or at least not
100% functional) because DHCP option 209 is not supported by the lwIP
library. Therefore, BOOTP_PXE_DHCP_OPTION cannot be enabled.

Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
Tested-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

The sprintf() etc. functions are supposed to return the length of the
string written, but do not. Fix this by checking the amount of buffer
space used.

Signed-off-by: Simon Glass <sjg@chromium.org>

After some header file cleanups to add missing include files, remove
common.h from all files in the lib directory. This primarily means just
dropping the line but in a few cases we need to add in other header
files now.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@konsulko.com>

Rename this option so that CONFIG_IS_ENABLED can be used with it.

Signed-off-by: Simon Glass <sjg@chromium.org>