[PATCH] env: Allow string CONFIG options in the text environment

[Simon Glass]

Sometimes it is useful to include a CONFIG option that contains a string.
This is hard to do in general, since in many cases it is useful to have
the quotes around the string so that, for example:

   bootcmd=run CONFIG_BOARD_CMD

becomes

   bootcmd=run "boot_board"

But for the special case where there is a single quoted, it seems
reasonable to suppress the quotes, so that:

   board=CONFIG_SYS_BOARD

becomes

   board=sandbox

Update the script, documentation and tests accordingly.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 doc/usage/environment.rst |  7 ++++++-
 scripts/env2string.awk    |  8 ++++++++
 test/py/tests/test_env.py | 10 +++++++++-
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/doc/usage/environment.rst b/doc/usage/environment.rst
index 15897f63dd9..7272c6abbb4 100644
--- a/doc/usage/environment.rst
+++ b/doc/usage/environment.rst
@@ -55,7 +55,12 @@ variable but assigning to a new one::
 
 This file can include C-style comments. Blank lines and multi-line
 variables are supported, and you can use normal C preprocessor directives
-and CONFIG defines from your board config also.
+and CONFIG defines from your board config also. If the CONFIG value consists of
+a string and this is the only thing in the variable, the quotes will be
+dropped::
+
+   something=CONFIG_SYS_BOARD
+   # where CONFIG_SYS_BOARD is "sandbox" this becomes: something=sandbox
 
 For example, for snapper9260 you would create a text file called
 `board/bluewater/snapper9260.env` containing the environment text.
diff --git a/scripts/env2string.awk b/scripts/env2string.awk
index de470a49941..3a0fac47d07 100644
--- a/scripts/env2string.awk
+++ b/scripts/env2string.awk
@@ -43,6 +43,14 @@ NF {
 		var = substr($0, 1, RLENGTH - 1)
 		env = substr($0, RLENGTH + 1)
 
+		# If the env value consists entirely of a quoted string, drop
+		# the quotes. This handles things like fred=CONFIG_SYS_BOARD
+		# which would otherwise result in fred=\"sandbox\" in this
+		# output and fred="sandbox" in the final environment.
+		if (length(env) != 0 && match(env, /^\\"([^"]*)\\"$/)) {
+			env = substr(env, RSTART + 2, RLENGTH - 4)
+		}
+
 		# Deal with += which concatenates the new string to the existing
 		# variable. Again we are careful to use POSIX match()
 		if (length(env) != 0 && match(var, "^(.*)[+]$")) {
diff --git a/test/py/tests/test_env.py b/test/py/tests/test_env.py
index 6d08565f0b5..9bec12a2269 100644
--- a/test/py/tests/test_env.py
+++ b/test/py/tests/test_env.py
@@ -588,8 +588,16 @@ e=456
 m+= 456''', 'e=456\\0m=123 456\\0')
 
     # contains quotes
+    check_script('''fred=run "my var"
+mary=another"''', 'fred=run \\"my var\\"\\0mary=another\\"\\0')
+
+    # contains only a quoted strings, so quotes are removed
     check_script('''fred="my var"
-mary=another"''', 'fred=\\"my var\\"\\0mary=another\\"\\0')
+mary=another"''', 'fred=my var\\0mary=another\\"\\0')
+
+    # contains more than one quoted string
+    check_script('''fred="my var" or "this var"
+mary=another"''', 'fred=\\"my var\\" or \\"this var\\"\\0mary=another\\"\\0')
 
     # variable name ending in +
     check_script('''fred\\+=my var
-- 
2.38.1.431.g37b22c650d-goog