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

Gerlando Falauto
2012-03-30T13:00:41Z

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

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);