While the `env export` can take as parameters variables to be exported,
`env import` does not have such a mechanism of variable selection.

Let's add the ability to add parameters at the end of the command for
variables to be imported.

Every env variable from the env to be imported passed by parameter to
this command will override the value of the variable in the current env.

If a variable exists in the current env but not in the imported env, if
this variable is passed as a parameter to env import, the variable will
be unset ONLY if the -d option is passed to env import, otherwise the
current value of the variable is kept.

If a variable exists in the imported env, the variable in the current
env will be set to the value of the one from the imported env.

All the remaining variables are left untouched.

As the size parameter of env import is positional but optional, let's
add the possibility to use the sentinel '-' for when we don't want to
give the size parameter (when the env is '\0' terminated) but we pass a
list of variables at the end of the command.

env import addr
env import addr -
env import addr size
env import addr - foo1 foo2
env import addr size foo1 foo2

are all valid.

env import -c addr
env import -c addr -
env import -c addr - foo1 foo2

are all invalid because they don't pass the size parameter required for
checking, while the following are valid.

env import addr size
env import addr size foo1 foo2

Nothing's changed for the other parameters or the overall behaviour.

One of its use case could be to load a secure environment from the
signed U-Boot binary and load only a handful of variables from an
other, unsecure, environment without completely losing control of
U-Boot.

Signed-off-by: Quentin Schulz <quentin.schulz@bootlin.com>
Tested-by: Alex Kiernan <alex.kiernan@gmail.com>
Tested-by: Stephen Warren <swarren@nvidia.com>

The error message should start with `## Error: ` so that it's easily
detectable by tests without needing to have a complex regexp for
matching all possible error message patterns.

Let's add the `## Error: ` prefix to the error messages since it's the
one already in use.

Suggested-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Quentin Schulz <quentin.schulz@bootlin.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Tested-by: Stephen Warren <swarren@nvidia.com>

The function set_default_env() sets the hashtable flags for import_r().
Formally set_default_env() doesn't accept flags from its callers. In
practice the caller can (un)set the H_INTERACTIVE flag, but it has to be
done using the first character of the function's string argument. Other
flags like H_FORCE can't be set by the caller.

Change the function to accept flags argument. The benefits are:
1. The caller will have to explicitly set the H_INTERACTIVE flag,
   instead of un-setting it using a special char in a string.
2. Add the ability to propagate flags from the caller to himport(),
   especially the H_FORCE flag from do_env_default() in nvedit.c that
   currently gets ignored for "env default -a -f" commands.
3. Flags and messages will not be coupled together. A caller will be
   able to set flags without passing a string and vice versa.

Please note:
The propagation of H_FORCE from do_env_default() does not introduce any
functional changes, because currently himport_r() is set to destroy the
old environment regardless if H_FORCE flag is set or not. More changes
are needed to utilize the propagation of H_FORCE.

Signed-off-by: Yaniv Levinsky <yaniv.levinsky@compulab.co.il>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>

The function set_default_vars() in common.c adds H_INTERACTIVE to the
h_import() flag, but the function has no way of telling if the command
actually was user directed like this flag suggest. The flag should be
set by the calling function do_env_default() in nvedit.c instead, where
the command is certainty user directed.

Move the H_INTERACTIVE flag from set_default_vars() to do_env_default().

Signed-off-by: Yaniv Levinsky <yaniv.levinsky@compulab.co.il>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>

The env_flag in do_env_default() doesn't get propagated and therefore
gets ignored by himport_r(). This breaks to ability to "forcibly" reset
variables to their default values using the environment command.

Scenario example of the problem:
	# setenv kernel uImage
	# setenv .flags kernel:so
	# env default -f kernel
	## Error: Can't overwrite "kernel"
	himport_r: can't insert "kernel=zImage" into hash table

Change the call path so it will pass the flag correctly.

Signed-off-by: Yaniv Levinsky <yaniv.levinsky@compulab.co.il>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>

The naming convention for flags in nvedit.c is:
* The hashtable flag (defined in search.h) is named "env_flag"
* The command flag argument (defined in command.h) is named "flag"

This convention is kept in functions like do_env_print(), do_env_set()
and do_env_delete(), but not in do_env_default().

Rename the hashtable flag in do_env_default() from "flag" to "env_flag".
Rename the command flag in do_env_default() from "__flag" to "flag".

No functional change.

Signed-off-by: Yaniv Levinsky <yaniv.levinsky@compulab.co.il>
Reviewed-by: Igor Grinberg <grinberg@compulab.co.il>

's/environemnt/environment/' and
	's/Environemnt/Environment/'

Signed-off-by: Shyam Saini <shyam@amarulasolutions.com>

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>

In order that we can use eth_env_* even when CONFIG_NET isn't set, move
these functions to environment code from net code.

This fixes failures such as:

  board/ti/am335x/built-in.o: In function `board_late_init':
  board/ti/am335x/board.c:752: undefined reference to `eth_env_set_enetaddr'
  u-boot/board/ti/am335x/board.c:766: undefined reference to `eth_env_set_enetaddr'

which caters for use cases such as:

commit f411b5cca48f ("board: am335x: Always set eth/eth1addr environment
variable")

when Ethernet is required in Linux, but not U-Boot.

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>

env_get_f calls env_get_char to load single characters from the
environment. However, the return value of env_get_char was not
checked for errors. Now if the env driver does not support the
.get_char call, env_get_f did not notice this and looped over the
whole size of the environment, calling env_get_char over 8000
times with the default settings, just to return an error in the
end.

Fix this by checking if env_get_char returns < 0.

Signed-off-by: Simon Goldschmidt <sgoldschmidt@de.pepperl-fuchs.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>