[PATCH v3] fff-gateway: Add sanity checks

[Fabian Bläse]

This adds two checks:
- Does gateway config exist?
- Does gateway config version match?

Signed-off-by: Fabian Bläse <fabian at blaese.de>
Tested-by: Fabian Bläse <fabian at blaese.de
---
Changes in v2:
- Add exit to gateway config check
- Fix incorrectly escaped apostrophe

Changes in v3:
- Move config_version option from gateway.version to gateway.meta
- Use uci show instead of undocumented use of uci get for existance test
- Remove '-q' from existance test to show uci error message (syntax errors for example)
---
 .../files/etc/gateway.d/01-version            | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)
 create mode 100644 src/packages/fff/fff-gateway/files/etc/gateway.d/01-version

diff --git a/src/packages/fff/fff-gateway/files/etc/gateway.d/01-version b/src/packages/fff/fff-gateway/files/etc/gateway.d/01-version
new file mode 100644
index 0000000..1553179
--- /dev/null
+++ b/src/packages/fff/fff-gateway/files/etc/gateway.d/01-version
@@ -0,0 +1,19 @@
+configure() {
+	local expected_version=1
+	local config_version=$(uci -q get gateway.meta.config_version)
+
+	# check if gateway config exists
+	if ! uci show gateway > /dev/null; then
+		echo "ERROR: Gateway config could not be parsed or does not exist."
+
+		exit 1
+	fi
+
+	# check version of configuration
+	if [ "$config_version" != "$expected_version" ]; then
+		echo "ERROR: Invalid config version. Expected '$expected_version', got '$config_version'."
+		echo "Please check what has been changed and adjust your config appropriately."
+
+		exit 1
+	fi
+}
-- 
2.23.0