Check driver capabilities before sr_config_get/set/list.

diff --git a/src/hwdriver.c b/src/hwdriver.c
index 24a52db3450864eb10ef7b4f6d10f4f48117fb43..fe2a85189bcb917bb8d0bff3196b78bf82bbcd31 100644 (file)
--- a/src/hwdriver.c
+++ b/src/hwdriver.c
@@ -419,6 +419,57 @@ SR_PRIV void sr_config_free(struct sr_config *src)
 
 }
 
+static int check_key(const struct sr_dev_driver *driver,
+               const struct sr_dev_inst *sdi, const struct sr_channel_group *cg,
+               uint32_t key, int op)
+{
+       const struct sr_config_info *srci;
+       gsize num_opts, i;
+       GVariant *gvar_opts;
+       const uint32_t *opts;
+       uint32_t pub_opt;
+       char *suffix, *opstr;
+
+       if (sdi && cg)
+               suffix = " for this device and channel group";
+       else if (sdi)
+               suffix = " for this device";
+       else
+               suffix = "";
+
+       if (!(srci = sr_config_info_get(key))) {
+               sr_err("Invalid key %d.", key);
+               return SR_ERR_ARG;
+       }
+       opstr = op == SR_CONF_GET ? "get" : op == SR_CONF_SET ? "set" : "list";
+
+       if (sr_config_list(driver, sdi, cg, SR_CONF_DEVICE_OPTIONS, &gvar_opts) != SR_OK) {
+               /* Driver publishes no options. */
+               sr_err("No options available%s.", srci->id, suffix);
+               return SR_ERR_ARG;
+       }
+       opts = g_variant_get_fixed_array(gvar_opts, &num_opts, sizeof(uint32_t));
+       pub_opt = 0;
+       for (i = 0; i < num_opts; i++) {
+               if ((opts[i] & SR_CONF_MASK) == key) {
+                       pub_opt = opts[i];
+                       break;
+               }
+       }
+       g_variant_unref(gvar_opts);
+       if (!pub_opt) {
+               sr_err("Option '%s' not available%s.", srci->id, suffix);
+               return SR_ERR_ARG;
+       }
+
+       if (!(pub_opt & op)) {
+               sr_err("Option '%s' not available to %s%s.", srci->id, opstr, suffix);
+               return SR_ERR_ARG;
+       }
+
+       return SR_OK;
+}
+
 /**
  * Query value of a configuration key at the given driver or device instance.
  *
@@ -456,6 +507,9 @@ SR_API int sr_config_get(const struct sr_dev_driver *driver,
        if (!driver->config_get)
                return SR_ERR_ARG;
 
+       if (check_key(driver, sdi, cg, key, SR_CONF_GET) != SR_OK)
+               return SR_ERR_ARG;
+
        if ((ret = driver->config_get(key, data, sdi, cg)) == SR_OK) {
                /* Got a floating reference from the driver. Sink it here,
                 * caller will need to unref when done with it. */
@@ -496,6 +550,8 @@ SR_API int sr_config_set(const struct sr_dev_inst *sdi,
                ret = SR_ERR;
        else if (!sdi->driver->config_set)
                ret = SR_ERR_ARG;
+       else if (check_key(sdi->driver, sdi, cg, key, SR_CONF_SET) != SR_OK)
+               return SR_ERR_ARG;
        else if ((ret = sr_variant_type_check(key, data)) == SR_OK)
                ret = sdi->driver->config_set(key, data, sdi, cg);
 
@@ -561,6 +617,10 @@ SR_API int sr_config_list(const struct sr_dev_driver *driver,
                ret = SR_ERR;
        else if (!driver->config_list)
                ret = SR_ERR_ARG;
+       else if (key != SR_CONF_SCAN_OPTIONS && key != SR_CONF_DEVICE_OPTIONS) {
+               if (check_key(driver, sdi, cg, key, SR_CONF_LIST) != SR_OK)
+                       return SR_ERR_ARG;
+       }
        else if ((ret = driver->config_list(key, data, sdi, cg)) == SR_OK)
                g_variant_ref_sink(*data);