[PATCH v3 2/2] bootconfig: Add append value operator support

Masami Hiramatsu
2020-02-21T08:31:32Z

Add append value operator "+=" support to bootconfig syntax.
With this operator, user can add new value to the key as
an entry of array instead of overwriting.
For example,

foo = bar
...
foo += baz

Then the key "foo" has "bar" and "baz" values as an array.

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
V3: update on value re-definition error patch.
---
Documentation/admin-guide/bootconfig.rst | 10 +++++++++-
lib/bootconfig.c | 15 +++++++++++----
tools/bootconfig/test-bootconfig.sh | 16 ++++++++++++++--
3 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst
index 9ee7650b7817..82a657096ebc 100644
--- a/Documentation/admin-guide/bootconfig.rst
+++ b/Documentation/admin-guide/bootconfig.rst
@@ -71,7 +71,15 @@ For example,::
foo = bar, baz
foo = qux # !ERROR! we can not re-define same key

-Also, a sub-key and a value can not co-exist under a parent key.
+If you want to append the value to existing key as an array member,
+you can use ``+=`` operator. For example::
+
+ foo = bar, baz
+ foo += qux
+
+In this case, the key ``foo`` has ``bar``, ``baz`` and ``qux``.
+
+However, a sub-key and a value can not co-exist under a parent key.
For example, following config is NOT allowed.::

foo = value1
diff --git a/lib/bootconfig.c b/lib/bootconfig.c
index 2ef304db31f2..ec3ce7fd299f 100644
--- a/lib/bootconfig.c
+++ b/lib/bootconfig.c
@@ -578,7 +578,7 @@ static int __init __xbc_parse_keys(char *k)
return __xbc_add_key(k);
}

-static int __init xbc_parse_kv(char **k, char *v)
+static int __init xbc_parse_kv(char **k, char *v, int op)
{
struct xbc_node *prev_parent = last_parent;
struct xbc_node *child;
@@ -593,7 +593,7 @@ static int __init xbc_parse_kv(char **k, char *v)
if (child) {
if (xbc_node_is_key(child))
return xbc_parse_error("Value is mixed with subkey", v);
- else
+ else if (op == '=')
return xbc_parse_error("Value is redefined", v);
}

@@ -774,7 +774,7 @@ int __init xbc_init(char *buf)

p = buf;
do {
- q = strpbrk(p, "{}=;\n#");
+ q = strpbrk(p, "{}=+;\n#");
if (!q) {
p = skip_spaces(p);
if (*p != '\0')
@@ -785,8 +785,15 @@ int __init xbc_init(char *buf)
c = *q;
*q++ = '\0';
switch (c) {
+ case '+':
+ if (*q++ != '=') {
+ ret = xbc_parse_error("Wrong '+' operator",
+ q - 2);
+ break;
+ }
+ /* Fall through */
case '=':
- ret = xbc_parse_kv(&p, q);
+ ret = xbc_parse_kv(&p, q, c);
break;
case '{':
ret = xbc_open_brace(&p, q);
diff --git a/tools/bootconfig/test-bootconfig.sh b/tools/bootconfig/test-bootconfig.sh
index adafb7c50940..1411f4c3454f 100755
--- a/tools/bootconfig/test-bootconfig.sh
+++ b/tools/bootconfig/test-bootconfig.sh
@@ -9,7 +9,7 @@ TEMPCONF=`mktemp temp-XXXX.bconf`
NG=0

cleanup() {
- rm -f $INITRD $TEMPCONF
+ rm -f $INITRD $TEMPCONF $OUTFILE
exit $NG
}

@@ -71,7 +71,6 @@ printf " \0\0\0 \0\0\0" >> $INITRD
$BOOTCONF -a $TEMPCONF $INITRD > $OUTFILE 2>&1
xfail grep -i "failed" $OUTFILE
xfail grep -i "error" $OUTFILE
-rm $OUTFILE

echo "Max node number check"

@@ -96,6 +95,19 @@ truncate -s 32764 $TEMPCONF
echo "\"" >> $TEMPCONF # add 2 bytes + terminal ('\"\n\0')
xpass $BOOTCONF -a $TEMPCONF $INITRD

+echo "Adding same-key values"
+cat > $TEMPCONF << EOF
+key = bar, baz
+key += qux
+EOF
+echo > $INITRD
+
+xpass $BOOTCONF -a $TEMPCONF $INITRD
+$BOOTCONF $INITRD > $OUTFILE
+xpass grep -q "bar" $OUTFILE
+xpass grep -q "baz" $OUTFILE
+xpass grep -q "qux" $OUTFILE
+
echo "=== expected failure cases ==="
for i in samples/bad-* ; do
xfail $BOOTCONF -a $i $INITRD