diff options
| author | Andrew Ruder <andrew.ruder@elecsyscorp.com> | 2013-10-22 19:07:34 -0500 |
|---|---|---|
| committer | Tom Rini <trini@ti.com> | 2013-11-08 09:38:24 -0500 |
| commit | 88733e2c65b1b118e6e1a942d62a48ce62a5ea40 (patch) | |
| tree | d34db65ce88b141c2b737a0767084a0899f17719 /common/cmd_nvedit.c | |
| parent | 8948794a273a6b4925d1acc5788ce804f0ceb410 (diff) | |
cmd_nvedit.c: Add env exists command
env exists is a way to test (in hush) if an environment variable
exists. A workaround existed using printenv but this new command
doesn't require all the stdout/stderr redirection to prevent
printing information to the screen.
Example:
$ set testexists 1
$ env exists testexists && echo "yes"
yes
$ env exists testexists || echo "no"
$ set testexists
$ env exists testexists && echo "yes"
$ env exists testexists || echo "no"
no
$
Signed-off-by: Andrew Ruder <andrew.ruder@elecsyscorp.com>
Diffstat (limited to 'common/cmd_nvedit.c')
| -rw-r--r-- | common/cmd_nvedit.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/common/cmd_nvedit.c b/common/cmd_nvedit.c index ba9ba16972c..0d4d02cfe0a 100644 --- a/common/cmd_nvedit.c +++ b/common/cmd_nvedit.c @@ -1059,6 +1059,23 @@ sep_err: } #endif +#if defined(CONFIG_CMD_ENV_EXISTS) +static int do_env_exists(cmd_tbl_t *cmdtp, int flag, int argc, + char * const argv[]) +{ + ENTRY e, *ep; + + if (argc < 2) + return CMD_RET_USAGE; + + e.key = argv[1]; + e.data = NULL; + hsearch_r(e, FIND, &ep, &env_htab, 0); + + return (ep == NULL) ? 1 : 0; +} +#endif + /* * New command line interface: "env" command with subcommands */ @@ -1094,6 +1111,9 @@ static cmd_tbl_t cmd_env_sub[] = { U_BOOT_CMD_MKENT(save, 1, 0, do_env_save, "", ""), #endif U_BOOT_CMD_MKENT(set, CONFIG_SYS_MAXARGS, 0, do_env_set, "", ""), +#if defined(CONFIG_CMD_ENV_EXISTS) + U_BOOT_CMD_MKENT(exists, 2, 0, do_env_exists, "", ""), +#endif }; #if defined(CONFIG_NEEDS_MANUAL_RELOC) @@ -1136,6 +1156,9 @@ static char env_help_text[] = #if defined(CONFIG_CMD_EDITENV) "env edit name - edit environment variable\n" #endif +#if defined(CONFIG_CMD_ENV_EXISTS) + "env exists name - tests for existence of variable\n" +#endif #if defined(CONFIG_CMD_EXPORTENV) "env export [-t | -b | -c] [-s size] addr [var ...] - export environment\n" #endif |