[U-Boot] [PATCH v2 3/3] env: make "env default" selective, check and apply

Marek Vasut
2012-03-30T13:09:42Z

Dear Gerlando Falauto,

> On 03/29/2012 10:25 PM, Marek Vasut wrote:
> > Dear Gerlando Falauto,
> >
> >> Changes in the syntax (user API) for "env default":
> >> -f: override write-once variables
> >> -a: all (resetting the whole env is NOT the default behavior)
> >>
> >> Signed-off-by: Gerlando Falauto<gerlando.falauto@keymile.com>
> >
> > I have to admit I'm not much of a fan of how you use this apply()
> > callback, is it really necessary?
>
> See my previous email.
>
> > Also, do we need special command for default env?
>
> I am sorry, I don't get the question. What do you mean?
> It's always the same "env import" with an augmented command line.
> If you're referring to CONFIG_CMD_DEFAULTENV_VARS, I don't think it's
> neeed either, but it was requested at some previous time.

Hmm.

> I also think it's misleading to have some syntax for the same command
> conditionally enabled. Has it ever been done before?

Yes it was, but this is creepy -- is this command displaying the compiled-in set
of env vars?

>
> Thank you,
> Gerlando
>
> > M
> >
> >> ---
> >>
> >> README | 2 ++
> >> common/cmd_nvedit.c | 43
> >>
> >> ++++++++++++++++++++++++++++++++++++------- common/env_common.c |
> >> 31 ++++++++++++++++++++++++++++++-
> >>
> >> include/config_cmd_all.h | 1 +
> >> include/environment.h | 5 +++++
> >> 5 files changed, 74 insertions(+), 8 deletions(-)
> >>
> >> diff --git a/README b/README
> >> index fda0190..e924575 100644
> >> --- a/README
> >> +++ b/README
> >>
> >> @@ -724,6 +724,8 @@ The following options need to be configured:
> >> CONFIG_CMD_CONSOLE coninfo
> >> CONFIG_CMD_CRC32 * crc32
> >> CONFIG_CMD_DATE * support for RTC, date/time...
> >>
> >> + CONFIG_CMD_DEFAULTENV_VARS
> >> + * Reset individual variables to default
> >>
> >> CONFIG_CMD_DHCP * DHCP support
> >> CONFIG_CMD_DIAG * Diagnostics
> >> CONFIG_CMD_DS4510 * ds4510 I2C gpio commands
> >>
> >> diff --git a/common/cmd_nvedit.c b/common/cmd_nvedit.c
> >> index 871b3b1..317bd1c 100644
> >> --- a/common/cmd_nvedit.c
> >> +++ b/common/cmd_nvedit.c
> >> @@ -674,14 +674,40 @@ int envmatch(uchar *s1, int i2)
> >>
> >> return -1;
> >>
> >> }
> >>
> >> -static int do_env_default(cmd_tbl_t *cmdtp, int flag,
> >> +static int do_env_default(cmd_tbl_t *cmdtp, int __flag,
> >>
> >> int argc, char * const argv[])
> >>
> >> {
> >>
> >> - if (argc != 2 || strcmp(argv[1], "-f") != 0)
> >> - return cmd_usage(cmdtp);
> >> -
> >> - set_default_env("## Resetting to default environment\n");
> >> - return 0;
> >> + int all = 0, flag = 0;
> >> + debug("Initial value for argc=%d\n", argc);
> >> + while (--argc> 0&& **++argv == '-') {
> >> + char *arg = *argv;
> >> + while (*++arg) {
> >> + switch (*arg) {
> >> + case 'a': /* default all */
> >> + all = 1;
> >> + break;
> >> + case 'f': /* force */
> >> + flag |= H_FORCE;
> >> + break;
> >> + default:
> >> + return cmd_usage(cmdtp);
> >> + }
> >> + }
> >> + }
> >> + debug("Final value for argc=%d\n", argc);
> >> + if (all&& (argc == 0)) {
> >> + /* Reset the whole environment */
> >> + set_default_env("## Resetting to default environment\n");
> >> + return 0;
> >> + }
> >> +#ifdef CONFIG_CMD_DEFAULTENV_VARS
> >> + if (!all&& (argc> 0)) {
> >> + /* Reset individual variables */
> >> + env_default_vars(argc, argv);
> >> + return 0;
> >> + }
> >> +#endif
> >> + return cmd_usage(cmdtp);
> >>
> >> }
> >>
> >> static int do_env_delete(cmd_tbl_t *cmdtp, int flag,
> >>
> >> @@ -1012,7 +1038,10 @@ U_BOOT_CMD(
> >>
> >> #if defined(CONFIG_CMD_ASKENV)
> >>
> >> "ask name [message] [size] - ask for environment variable\nenv "
> >>
> >> #endif
> >>
> >> - "default -f - reset default environment\n"
> >> + "default [-f] -a - [forcibly] reset default environment\n"
> >> +#if defined(CONFIG_CMD_DEFAULTENV_VARS)
> >> + "env default [-f] var [...] - [forcibly] reset variable(s) to their
> >> default values\n" +#endif
> >>
> >> #if defined(CONFIG_CMD_EDITENV)
> >>
> >> "env edit name - edit environment variable\n"
> >>
> >> #endif
> >>
> >> diff --git a/common/env_common.c b/common/env_common.c
> >> index 7e2bb2f..56719a6 100644
> >> --- a/common/env_common.c
> >> +++ b/common/env_common.c
> >> @@ -157,6 +157,11 @@ const uchar *env_get_addr(int index)
> >>
> >> void set_default_env(const char *s)
> >> {
> >>
> >> + /*
> >> + * By default, do not apply changes as they will eventually
> >> + * be applied by someone else
> >> + */
> >> + apply_cb apply_function = NULL;
> >>
> >> if (sizeof(default_environment)> ENV_SIZE) {
> >>
> >> puts("*** Error - default environment is too large\n\n");
> >> return;
> >>
> >> @@ -168,6 +173,14 @@ void set_default_env(const char *s)
> >>
> >> "using default environment\n\n",
> >> s + 1);
> >>
> >> } else {
> >>
> >> + /*
> >> + * This set_to_default was explicitly asked for
> >> + * by the user, as opposed to being a recovery
> >> + * mechanism. Therefore we chack every single
> >> + * variable and apply changes to the system
> >> + * right away (e.g. baudrate, console).
> >> + */
> >> + apply_function = env_check_apply;
> >>
> >> puts(s);
> >>
> >> }
> >>
> >> } else {
> >>
> >> @@ -176,12 +189,28 @@ void set_default_env(const char *s)
> >>
> >> if (himport_r(&env_htab, (char *)default_environment,
> >>
> >> sizeof(default_environment), '\0', 0,
> >>
> >> - 0, NULL, NULL) == 0)
> >> + 0, NULL, apply_function) == 0)
> >>
> >> error("Environment import failed: errno = %d\n", errno);
> >>
> >> gd->flags |= GD_FLG_ENV_READY;
> >>
> >> }
> >>
> >> +#ifdef CONFIG_CMD_DEFAULTENV_VARS
> >> +
> >> +/* [re]set individual variables to their value in the default
> >> environment */ +int env_default_vars(int nvars, char * const vars[])
> >> +{
> >> + /*
> >> + * Special use-case: import from default environment
> >> + * (and use \0 as a separator)
> >> + */
> >> + return himport_r(&env_htab, (const char *)default_environment,
> >> + sizeof(default_environment), '\0', H_NOCLEAR,
> >> + nvars, vars, env_check_apply);
> >> +}
> >> +
> >> +#endif /* CONFIG_CMD_DEFAULTENV_VARS */
> >> +
> >>
> >> /*
> >>
> >> * Check if CRC is valid and (if yes) import the environment.
> >> * Note that "buf" may or may not be aligned.
> >>
> >> diff --git a/include/config_cmd_all.h b/include/config_cmd_all.h
> >> index 9716f9c..e728eae 100644
> >> --- a/include/config_cmd_all.h
> >> +++ b/include/config_cmd_all.h
> >> @@ -25,6 +25,7 @@
> >>
> >> #define CONFIG_CMD_CDP /* Cisco Discovery Protocol */
> >> #define CONFIG_CMD_CONSOLE /* coninfo */
> >> #define CONFIG_CMD_DATE /* support for RTC, date/time...*/
> >>
> >> +#define CONFIG_CMD_DEFAULTENV_VARS /* default individ variables */
> >>
> >> #define CONFIG_CMD_DHCP /* DHCP Support */
> >> #define CONFIG_CMD_DIAG /* Diagnostics */
> >> #define CONFIG_CMD_DISPLAY /* Display support */
> >>
> >> diff --git a/include/environment.h b/include/environment.h
> >> index 3a3e6b8..8f0d4db 100644
> >> --- a/include/environment.h
> >> +++ b/include/environment.h
> >> @@ -190,6 +190,11 @@ void env_crc_update(void);
> >>
> >> /* [re]set to the default environment */
> >> void set_default_env(const char *s);
> >>
> >> +#ifdef CONFIG_CMD_DEFAULTENV_VARS
> >> +/* [re]set individual variables to their value in the default
> >> environment */ +int env_default_vars(int nvars, char * const vars[]);
> >> +#endif
> >> +
> >>
> >> /* Import from binary representation into hash table */
> >> int env_import(const char *buf, int check);