nbd-proxy: Add metadata facility
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
diff --git a/config.sample.json b/config.sample.json
index dc8e0f2..461046a 100644
--- a/config.sample.json
+++ b/config.sample.json
@@ -2,7 +2,10 @@
"timeout": 30,
"configurations": {
"0": {
- "nbd-device": "/dev/nbd0"
+ "nbd-device": "/dev/nbd0",
+ "metadata": {
+ "description": "Virtual media device"
+ }
}
}
}
diff --git a/nbd-proxy.c b/nbd-proxy.c
index 3ce8879..6b23d6a 100644
--- a/nbd-proxy.c
+++ b/nbd-proxy.c
@@ -389,6 +389,24 @@
return rc ? -1 : 0;
}
+static void print_metadata(struct ctx *ctx)
+{
+ struct json_object *md;
+ int i;
+
+ md = json_object_new_object();
+
+ for (i = 0; i < ctx->n_configs; i++) {
+ struct config *config = &ctx->configs[i];
+ json_object_object_add(md, config->name,
+ config->metadata);
+ }
+
+ puts(json_object_get_string(md));
+
+ json_object_put(md);
+}
+
static void config_free_one(struct config *config)
{
if (config->metadata)
@@ -548,17 +566,26 @@
}
static const struct option options[] = {
- { .name = "help", .val = 'h' },
+ { .name = "help", .val = 'h' },
+ { .name = "metadata", .val = 'm' },
{ 0 },
};
+enum action {
+ ACTION_PROXY,
+ ACTION_METADATA,
+};
+
static void print_usage(const char *progname)
{
- fprintf(stderr, "usage: %s [configuration]\n", progname);
+ fprintf(stderr, "usage:\n");
+ fprintf(stderr, "\t%s [configuration]\n", progname);
+ fprintf(stderr, "\t%s --metadata\n", progname);
}
int main(int argc, char **argv)
{
+ enum action action = ACTION_PROXY;
const char *config_name;
struct ctx _ctx, *ctx;
int rc;
@@ -571,6 +598,9 @@
break;
switch (c) {
+ case 'm':
+ action = ACTION_METADATA;
+ break;
case 'h':
case '?':
print_usage(argv[0]);
@@ -590,6 +620,11 @@
if (rc)
goto out_free;
+ if (action == ACTION_METADATA) {
+ print_metadata(ctx);
+ goto out_free;
+ }
+
rc = config_select(ctx, config_name);
if (rc)
goto out_free;