| Message ID | 20211220183156.1910e71b.samuel@dionne-riel.com |
|---|---|
| State | Accepted |
| Delegated to: | Tom Rini |
| Headers | show |
| Series | cmd: env: Add `indirect` to indirectly set values | expand |
Hi Samuel, On Mon, 20 Dec 2021 at 16:32, Samuel Dionne-Riel <samuel@dionne-riel.com> wrote: > > This allows an ergonomic-enough approximation of ${!variable} expansion. > This could be used the following way: > > ``` > for target in ${boot_targets}; do > env indirect target_name target_name_${target} > # ... > done > ``` How is this different from: for target in ${boot_targets}; do env set target_name target_name_${target} # ... done Can you add a few more details? Also needs some sort of update to doc/ > Assuming `target_name_mmc0` and similar are set appropriately. > > A default value can be optionally provided. > > Note: this acts on environment variables, not hush variables. > > Signed-off-by: Samuel Dionne-Riel <samuel@dionne-riel.com> > Cc: Simon Glass <sjg@chromium.org> > Cc: "Marek Behún" <marek.behun@nic.cz> > --- > cmd/Kconfig | 4 ++++ > cmd/nvedit.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 49 insertions(+) Regards, Simon
On Mon, Dec 20, 2021 at 06:31:56PM -0500, Samuel Dionne-Riel wrote: > This allows an ergonomic-enough approximation of ${!variable} expansion. > This could be used the following way: > > ``` > for target in ${boot_targets}; do > env indirect target_name target_name_${target} > # ... > done > ``` > > Assuming `target_name_mmc0` and similar are set appropriately. > > A default value can be optionally provided. > > Note: this acts on environment variables, not hush variables. > > Signed-off-by: Samuel Dionne-Riel <samuel@dionne-riel.com> > Cc: Simon Glass <sjg@chromium.org> > Cc: "Marek Behún" <marek.behun@nic.cz> After making this not default y, applied to u-boot/master, thanks!
diff --git a/cmd/Kconfig b/cmd/Kconfig index 26d5707f75..e538e69a11 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -508,6 +508,10 @@ config CMD_NVEDIT_EFI If enabled, we are allowed to set/print UEFI variables using "env" command with "-e" option without knowing details. +config CMD_NVEDIT_INDIRECT + bool "env indirect - Sets environment value from another" + default y + config CMD_NVEDIT_INFO bool "env info - print or evaluate environment information" help diff --git a/cmd/nvedit.c b/cmd/nvedit.c index 3bb6e764c0..53e6b57b60 100644 --- a/cmd/nvedit.c +++ b/cmd/nvedit.c @@ -1018,6 +1018,45 @@ sep_err: } #endif +#if defined(CONFIG_CMD_NVEDIT_INDIRECT) +static int do_env_indirect(struct cmd_tbl *cmdtp, int flag, + int argc, char *const argv[]) +{ + char *to = argv[1]; + char *from = argv[2]; + char *default_value = NULL; + int ret = 0; + + if (argc < 3 || argc > 4) { + return CMD_RET_USAGE; + } + + if (argc == 4) { + default_value = argv[3]; + } + + if (env_get(from) == NULL && default_value == NULL) { + printf("## env indirect: Environment variable for <from> (%s) does not exist.\n", from); + + return CMD_RET_FAILURE; + } + + if (env_get(from) == NULL) { + ret = env_set(to, default_value); + } + else { + ret = env_set(to, env_get(from)); + } + + if (ret == 0) { + return CMD_RET_SUCCESS; + } + else { + return CMD_RET_FAILURE; + } +} +#endif + #if defined(CONFIG_CMD_NVEDIT_INFO) /* * print_env_info - print environment information @@ -1181,6 +1220,9 @@ static struct cmd_tbl cmd_env_sub[] = { #if defined(CONFIG_CMD_IMPORTENV) U_BOOT_CMD_MKENT(import, 5, 0, do_env_import, "", ""), #endif +#if defined(CONFIG_CMD_NVEDIT_INDIRECT) + U_BOOT_CMD_MKENT(indirect, 3, 0, do_env_indirect, "", ""), +#endif #if defined(CONFIG_CMD_NVEDIT_INFO) U_BOOT_CMD_MKENT(info, 3, 0, do_env_info, "", ""), #endif @@ -1265,6 +1307,9 @@ static char env_help_text[] = #if defined(CONFIG_CMD_IMPORTENV) "env import [-d] [-t [-r] | -b | -c] addr [size] [var ...] - import environment\n" #endif +#if defined(CONFIG_CMD_NVEDIT_INDIRECT) + "env indirect <to> <from> [default] - sets <to> to the value of <from>, using [default] when unset\n" +#endif #if defined(CONFIG_CMD_NVEDIT_INFO) "env info - display environment information\n" "env info [-d] [-p] [-q] - evaluate environment information\n"
This allows an ergonomic-enough approximation of ${!variable} expansion. This could be used the following way: ``` for target in ${boot_targets}; do env indirect target_name target_name_${target} # ... done ``` Assuming `target_name_mmc0` and similar are set appropriately. A default value can be optionally provided. Note: this acts on environment variables, not hush variables. Signed-off-by: Samuel Dionne-Riel <samuel@dionne-riel.com> Cc: Simon Glass <sjg@chromium.org> Cc: "Marek Behún" <marek.behun@nic.cz> --- cmd/Kconfig | 4 ++++ cmd/nvedit.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 49 insertions(+)