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

[Eric Nelson (Boundary Devices)]

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 at 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(
-- 
1.5.5.1.382.g182fb