[U-Boot] [PATCH] Add support for setting environment variable from RAM.

This is useful for allowing scripts to read environment variables from file, among other things.
This is a slightly modified version of what Alessandro submitted to the mailing list last July: http://www.mail-archive.com/u-boot-users@lists.sourceforge.net/msg07932.html
I changed the name from 'setenvram' to 'ramenv' to prevent breakage of scripts that use the abbreviation 'set' (which my handss have the habit of doing).
Signed-off-by: Eric Nelson eric.nelson@boundarydevices.com --- common/cmd_nvedit.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 46 insertions(+), 0 deletions(-)
diff --git a/common/cmd_nvedit.c b/common/cmd_nvedit.c index 1fcb4c9..bcb6d9f 100644 --- a/common/cmd_nvedit.c +++ b/common/cmd_nvedit.c @@ -494,6 +494,44 @@ int do_askenv ( cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) #endif
/************************************************************************ + * Set a new environment variable from RAM. + * Requires three arguments: the variable name, a memory address and a length. + * + * Deletes the environment variable if the length is zero. + */ +int do_ramenv(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) +{ + unsigned long len, i; + char *addr; + + if (argc != 4) { + cmd_usage(cmdtp); + return 1; + } + addr = (char *)simple_strtol(argv[2], NULL, 16); + len = simple_strtol(argv[3], NULL, 16); + if (!addr || !len) { + cmd_usage(cmdtp); + return 1; + } + addr[len] = '\0'; + for (i = 0; i < len; i++) { + /* turn newlines into semicolon */ + if (addr[i] == '\n') + addr[i] = ';'; /* ignore dos-style newlines */ + if (addr[i] == '\r') + addr[i] = ' '; /* accept sh-comments and discard them */ + if (addr[i] == '#') { + while (addr[i] && addr[i] != '\n') + addr[i++] = ' '; + i--; + } + } + setenv(argv[1], addr); + return 0; +} + +/************************************************************************ * Look up variable from environment, * return address of storage for that variable, * or NULL if not found @@ -605,6 +643,14 @@ U_BOOT_CMD( " - delete environment variable 'name'\n" );
+U_BOOT_CMD( + ramenv, 4, 0, do_ramenv, + "ramenv - get environment variable from ram\n", + "name addr maxlen\n" + " - set environment variable 'name' from addr 'addr'\n" + " - delete environment variable if maxlen is 0\n" +); + #if defined(CONFIG_CMD_ASKENV)
U_BOOT_CMD(

Dear "Eric Nelson (Boundary Devices)",
In message 1233631739-17568-1-git-send-email-eric.nelson@boundarydevices.com you wrote:
This is useful for allowing scripts to read environment variables from file, among other things.
This is a slightly modified version of what Alessandro submitted to the mailing list last July: http://www.mail-archive.com/u-boot-users@lists.sourceforge.net/msg07932.html
I changed the name from 'setenvram' to 'ramenv' to prevent breakage of scripts that use the abbreviation 'set' (which my handss have the habit of doing).
Signed-off-by: Eric Nelson eric.nelson@boundarydevices.com
We discussed thsi before, and I already NAKed it.
I hereby NAK it again.
This command makes no sense (especially since it will process only a single variable).
Please use a script image with "askenv" instead.
Note: if the code would process a list of variables, say, in internal U-Boot environment format (separated by single NUL, terminated by double NUL characters), that could be a useful building block to implement the "reset to default environment" / "reset factory defaults" command we discussed earlier (see mailing list archive) - and as such, it had much better chances to be considered.
Best regards,
Wolfgang Denk

Wolfgang Denk wrote:
Dear "Eric Nelson (Boundary Devices)",
In message 1233631739-17568-1-git-send-email-eric.nelson@boundarydevices.com you wrote:
This is useful for allowing scripts to read environment variables from file, among other things.
This is a slightly modified version of what Alessandro submitted to the mailing list last July: http://www.mail-archive.com/u-boot-users@lists.sourceforge.net/msg07932.html
I changed the name from 'setenvram' to 'ramenv' to prevent breakage of scripts that use the abbreviation 'set' (which my handss have the habit of doing).
Signed-off-by: Eric Nelson eric.nelson@boundarydevices.com
We discussed thsi before, and I already NAKed it.
I hereby NAK it again.
I'm not sure how this made it back onto the list. Sorry about that.
This command makes no sense (especially since it will process only a single variable).
Please use a script image with "askenv" instead.
Thanks for the tip. I hadn't noticed askenv previously.
Note: if the code would process a list of variables, say, in internal U-Boot environment format (separated by single NUL, terminated by double NUL characters), that could be a useful building block to implement the "reset to default environment" / "reset factory defaults" command we discussed earlier (see mailing list archive) - and as such, it had much better chances to be considered.
Best regards,
Wolfgang Denk

Dear Eric Nelson,
In message 498B56FE.1080507@boundarydevices.com you wrote:
Please use a script image with "askenv" instead.
Thanks for the tip. I hadn't noticed askenv previously.
Sorry, typo. I meant "autoscr".
Best regards,
Wolfgang Denk

Wolfgang Denk wrote:
Dear Eric Nelson,
In message 498B56FE.1080507@boundarydevices.com you wrote:
Please use a script image with "askenv" instead.
Thanks for the tip. I hadn't noticed askenv previously.
Sorry, typo. I meant "autoscr".
Muscle memory. Can't live with it, can't turn it off...
Still and all, askenv's kinda cool.
Thanks,
Eric
participants (3)
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Eric Nelson
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Eric Nelson (Boundary Devices)
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Wolfgang Denk