Re: [PATCH v12 00/24] Modernize U-Boot shell

neil.armstrong
2023-12-13T09:35:48Z

On 08/12/2023 23:30, Francis Laniel wrote:
> Hi.
>
>
> During 2021 summer, Sean Anderson wrote a contribution to add a new shell, based
> on LIL, to U-Boot [1, 2].
> While one of the goals of this contribution was to address the fact actual
> U-Boot shell, which is based on Busybox hush, is old there was a discussion
> about adding a new shell versus updating the actual one [3, 4].
>
> So, in this series, with Harald Seiler, we updated the actual U-Boot shell to
> reflect what is currently in Busybox source code.
> Basically, this contribution is about taking a snapshot of Busybox shell/hush.c
> file (as it exists in commit 37460f5da) and adapt it to suit U-Boot needs.
>
> This contribution was written to be as backward-compatible as possible to avoid
> breaking the existing.
> So, the modern hush flavor offers the same as the actual, that is to say:
> 1. Variable expansion.
> 2. Instruction lists (;, && and ||).
> 3. If, then and else.
> 4. Loops (for, while and until).
> No new features offered by Busybox hush were implemented (e.g. functions).
>
> It is possible to change the parser at runtime using the "cli" command:
> => cli print
> old
> => cli set modern
> => cli print
> modern
> => cli set old
> The default parser is the old one.
> Note that to use both parser, you would need to set both
> CONFIG_HUSH_MODERN_PARSER and CONFIG_HUSH_OLD_PARSER.
>
> In terms of testing, new unit tests were added to ut to ensure the new behavior
> is the same as the old one and it does not add regression.
> Nonetheless, if old behavior was buggy and fixed upstream, the fix is then added
> to U-Boot [5].
> In sandbox, all of these tests pass smoothly:
> => printenv board
> board=sandbox
> => ut hush
> Running 20 hush tests
> ...
> Failures: 0
> => cli set modern
> => ut hush
> Running 20 hush tests
> ...
> Failures: 0
>
> Thanks to the effort of Harald Seiler, I was successful booting a board:
> => printenv fdtfile
> fdtfile=amlogic/meson-gxl-s905x-libretech-cc.dtb
> => cli get
> old
> => boot
> ...
> root@lepotato:~#
> root@lepotato:~# reboot
> ...
> => cli set modern
> => cli get
> modern
> => printenv fdtfile
> fdtfile=amlogic/meson-gxl-s905x-libretech-cc.dtb
> => boot
> ...
> root@lepotato:~#
>
> This contribution indeed adds a lot of code and there were concern about its
> size [6, 7].
> With regard to the amount of code added, the cli_hush_upstream.c is 13030 lines
> long but it seems a smaller subset is really used:
> gcc -D__U_BOOT__ -E common/cli_hush_upstream.c | wc -l
> 2870
> Despite this, it is better to still have the whole upstream code for the sake of
> easing maintenance.
> With regard to memory size, I conducted some experiments for version 8 of this
> series and for a subset of arm64 boards and found the worst case to be 4K [8].
> Tom Rini conducted more research on this and also found the increase to be
> acceptable [9].
>
> If you want to review it - your review will really be appreciated - here are
> some information regarding the commits:
> * commits marked as "test:" deal with unit tests.
> * commit "cli: Add Busybox upstream hush.c file." copies Busybox shell/hush.c
> into U-Boot tree, this explain why this commit contains around 12000 additions.
> * commit "cli: Port Busybox 2021 hush to U-Boot." modifies previously added file
> to permit us to use this as new shell.
> The really good idea of #include'ing Busybox code into a wrapper file to define
> some particular functions while minimizing modifications to upstream code comes
> from Harald Seiler.
> * commit "cmd: Add new parser command" adds a new command which permits
> selecting parser at runtime.
> I am not really satisfied with the fact it calls cli_init() and cli_loop() each
> time the parser is set, so your reviews would be welcomed.
> * Other commits focus on enabling features we need (e.g. if).
>
> Changes since:
> v2:
> * Added a small fix to compile sandbox with NO_SDL=1.
> * Added a command to change parser at runtime.
> * Added 2021 parser function to all run_command*().
> v3:
> * Various bug fixes pointed by the CI.
> * Added upstream busybox hush commits until 6th February 2022.
> v4:
> * Various cleaning.
> * Modified python test to accept failure output when the test are designed to
> fail.
> * Bumped upstream busybox hush commits until 24h March 2022.
> v5:
> * Bumped upstream busybox hush commits until 30th January 2023.
> * Fix how hush interprets '<' and '>', indeed we needed to escape them but I
> removed this behavior as tests are handled by test command and not hush
> itself. This permitted to have the ut fdt to pass.
> * Fix a problem with how exit was handled. This was reported by the ut exit
> test.
> v6:
> * There was no v6 and I got mixed up with version.
> v7:
> * Bumped upstream busybox hush commits until 9th May 2023.
> * Renamed parser command to change parser at runtime to cli and added
> documentation.
> * Added better separation of patches.
> * Removed code about __gnu_thumb1_case_si as it was merged in another series.
> * Various cleaning.
> v8:
> * Bumped upstream busybox hush commits until 25th May 2023.
> v9:
> * Bumped upstream busybox hush commits until 2nd October 2023.
> v10:
> * Fixed a build error in commit adding cli command.
> * Add new CONFIG_HUSH_SELECTABLE to only build cli command if the two shell
> flavors are selected.
> v11:
> * Renamed everything containing 2021 to modern.
> * Fixed cmd Kconfig indentation.
> * Set modern parser as default for majority of boards except some.
>
> Francis Laniel (24):
> test: Add framework to test hush behavior
> test: hush: Test hush if/else
> test/py: hush_if_test: Remove the test file
> test: hush: Test hush variable expansion
> test: hush: Test hush commands list
> test: hush: Test hush loops
> cli: Add Busybox upstream hush.c file
> cli: Port upstream Busybox hush to U-Boot
> cli: Add menu for hush parser
> global_data.h: add GD_FLG_HUSH_OLD_PARSER flag
> cmd: Add new cli command
> cli: Enables using modern hush parser as command line parser
> cli: hush_modern: Enable variables expansion for modern hush
> cli: hush_modern: Add functions to be called from run_command()
> cli: add modern hush as parser for run_command*()
> test: hush: Fix instructions list tests for modern hush
> test: hush: Fix variable expansion tests for modern hush
> cli: hush_modern: Enable using < and > as string compare operators
> cli: hush_modern: Enable if keyword
> cli: hush_modern: Enable loops
> test: hush: Fix loop tests for modern hush
> cli: modern_hush: Add upstream commits up to 2nd October 2023.
> cmd: Set modern hush as default shell
> configs: Use old hush for several boards
>
> cmd/Kconfig | 21 +
> cmd/Makefile | 2 +
> cmd/cli.c | 134 +
> common/Makefile | 3 +-
> common/cli.c | 82 +-
> common/cli_hush_modern.c | 324 +
> common/cli_hush_upstream.c | 13030 +++++++++++++++++++++++
> configs/kmcent2_defconfig | 1 +
> configs/kmcoge5ne_defconfig | 1 +
> configs/kmeter1_defconfig | 1 +
> configs/kmopti2_defconfig | 1 +
> configs/kmsupx5_defconfig | 1 +
> configs/kmtepr2_defconfig | 1 +
> configs/pg_wcom_expu1_defconfig | 1 +
> configs/pg_wcom_expu1_update_defconfig | 1 +
> configs/pg_wcom_seli8_defconfig | 1 +
> configs/pg_wcom_seli8_update_defconfig | 1 +
> configs/socfpga_secu1_defconfig | 1 +
> configs/tuge1_defconfig | 1 +
> configs/tuxx1_defconfig | 1 +
> doc/usage/cmd/cli.rst | 74 +
> doc/usage/index.rst | 1 +
> include/asm-generic/global_data.h | 8 +
> include/cli_hush.h | 51 +-
> include/test/hush.h | 15 +
> include/test/suites.h | 1 +
> test/Makefile | 3 +
> test/cmd_ut.c | 6 +
> test/hush/Makefile | 10 +
> test/hush/cmd_ut_hush.c | 20 +
> test/hush/dollar.c | 226 +
> test/hush/if.c | 316 +
> test/hush/list.c | 140 +
> test/hush/loop.c | 91 +
> test/py/tests/test_hush_if_test.py | 197 -
> test/py/tests/test_ut.py | 8 +-
> 36 files changed, 14565 insertions(+), 211 deletions(-)
> create mode 100644 cmd/cli.c
> create mode 100644 common/cli_hush_modern.c
> create mode 100644 common/cli_hush_upstream.c
> create mode 100644 doc/usage/cmd/cli.rst
> create mode 100644 include/test/hush.h
> create mode 100644 test/hush/Makefile
> create mode 100644 test/hush/cmd_ut_hush.c
> create mode 100644 test/hush/dollar.c
> create mode 100644 test/hush/if.c
> create mode 100644 test/hush/list.c
> create mode 100644 test/hush/loop.c
> delete mode 100644 test/py/tests/test_hush_if_test.py
>
>
> Best regards and thank you in advance.
> ---
> [1] https://lists.denx.de/pipermail/u-boot/2021-July/453347.html
> [2] https://runtimeterror.com/tech/lil/
> [3] https://lists.denx.de/pipermail/u-boot/2021-July/453790.html
> [4] https://lists.denx.de/pipermail/u-boot/2021-July/453848.html
> [5] https://lists.denx.de/pipermail/u-boot/2021-August/458569.html
> [6] https://lists.denx.de/pipermail/u-boot/2023-November/536768.html
> [7] https://lists.denx.de/pipermail/u-boot/2023-May/518140.html
> [8] https://lists.denx.de/pipermail/u-boot/2023-May/518147.html
> [9] https://lists.denx.de/pipermail/u-boot/2023-November/536952.html
> --
> 2.34.1
>

Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on libretech-ac
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on libretech-cc
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on bananapi-m2s
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on bananapi-m5

For reference:
https://gitlab.com/amlogic-foss/amlogic-u-boot-autotest/-/pipelines/1105162563/test_report

Thanks !
Neil