env: make "env default" selective, check and apply

[platform/kernel/u-boot.git] / common / env_common.c

diff --git a/common/env_common.c b/common/env_common.c
index b9865bf..3e46c26 100644 (file)
--- a/common/env_common.c
+++ b/common/env_common.c
@@ -180,6 +180,11 @@ 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
+        */
+       int do_apply = 0;
        if (sizeof(default_environment) > ENV_SIZE) {
                puts("*** Error - default environment is too large\n\n");
                return;
@@ -191,6 +196,14 @@ 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 check every single
+                        * variable and apply changes to the system
+                        * right away (e.g. baudrate, console).
+                        */
+                       do_apply = 1;
                        puts(s);
                }
        } else {
@@ -199,12 +212,25 @@ void set_default_env(const char *s)
 
        if (himport_r(&env_htab, (char *)default_environment,
                        sizeof(default_environment), '\0', 0,
-                       0, NULL, 0 /* do_apply */) == 0)
+                       0, NULL, do_apply) == 0)
                error("Environment import failed: errno = %d\n", errno);
 
        gd->flags |= GD_FLG_ENV_READY;
 }
 
+
+/* [re]set individual variables to their value in the default environment */
+int set_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, 1 /* do_apply */);
+}
+
 /*
  * Check if CRC is valid and (if yes) import the environment.
  * Note that "buf" may or may not be aligned.