+static unsigned long ht_hash_event(void *_key, unsigned long seed)
+{
+ uint64_t xored_key;
+ struct ust_registry_event *key = _key;
+
+ assert(key);
+
+ xored_key = (uint64_t) (hash_key_str(key->name, seed) ^
+ hash_key_str(key->signature, seed));
+
+ return hash_key_u64(&xored_key, seed);
+}
+
+/*
+ * Return negative value on error, 0 if OK.
+ *
+ * TODO: we could add stricter verification of more types to catch
+ * errors in liblttng-ust implementation earlier than consumption by the
+ * trace reader.
+ */
+static
+int validate_event_field(struct ustctl_field *field,
+ const char *event_name,
+ struct ust_app *app)
+{
+ switch(field->type.atype) {
+ case ustctl_atype_integer:
+ case ustctl_atype_enum:
+ case ustctl_atype_array:
+ case ustctl_atype_sequence:
+ case ustctl_atype_string:
+ break;
+
+ case ustctl_atype_float:
+ switch (field->type.u.basic._float.mant_dig) {
+ case 0:
+ WARN("UST application '%s' (pid: %d) has unknown float mantissa '%u' "
+ "in field '%s', rejecting event '%s'",
+ app->name, app->pid,
+ field->type.u.basic._float.mant_dig,
+ field->name,
+ event_name);
+ return -EINVAL;
+ default:
+ break;
+ }
+ break;
+
+ default:
+ return -ENOENT;
+ }
+ return 0;
+}
+
+static
+int validate_event_fields(size_t nr_fields, struct ustctl_field *fields,
+ const char *event_name, struct ust_app *app)
+{
+ unsigned int i;
+
+ for (i = 0; i < nr_fields; i++) {
+ if (validate_event_field(&fields[i], event_name, app) < 0)
+ return -EINVAL;
+ }
+ return 0;
+}
+