conf: Warn at startup if stratum.username_modifiers fails to fully distribute shares

Author: luke-jr

src/datum_conf.c

@@ -251,7 +251,7 @@ void datum_config_set_default(const T_DATUM_CONFIG_ITEM *c) {
 	}
 }
 
-int datum_config_parse_username_mods(struct datum_username_mod ** const umods_p, json_t * const item) {
+int datum_config_parse_username_mods(struct datum_username_mod ** const umods_p, json_t * const item, const bool log_errors) {
 	if (!json_object_size(item)) {
 		if (json_is_null(item) || json_is_object(item)) {
 			free(*umods_p);
@@ -316,6 +316,11 @@ int datum_config_parse_username_mods(struct datum_username_mod ** const umods_p,
 			++addr_range;
 			if (nonce_max == 0xffff) break;
 		}
+		if (log_errors && (addr_range == umod->ranges || addr_range[-1].max != 0xffff)) {
+			double missing_percent = 100 * (1 - sum);
+			const unsigned int missing_percent_precision = datum_double_precision(&missing_percent);
+			DLOG_ERROR("Username modifier '%s' is configured to not distribute %.*f%% of shares!", modname, missing_percent_precision, missing_percent);
+		}
 		addr_range[0].addr = NULL;
 		assert((uint8_t*)addr_range <= &((uint8_t*)umod)[umod->sz]);  // otherwise we overwrote strings!
 		assert(p <= &((uint8_t*)*umods_p)[sz]);  // otherwise we overran the buffer!
@@ -398,7 +403,7 @@ int datum_config_parse_value(const T_DATUM_CONFIG_ITEM *c, json_t *item) {
 		}
 
 		case DATUM_CONF_USERNAME_MODS: {
-			return datum_config_parse_username_mods(c->ptr, item);
+			return datum_config_parse_username_mods(c->ptr, item, true);
 		}
 	}
 

src/datum_conf.h

@@ -91,7 +91,7 @@ struct datum_username_mod {
 	struct datum_addr_range ranges[];
 };
 
-int datum_config_parse_username_mods(struct datum_username_mod **umods_p, json_t *item);
+int datum_config_parse_username_mods(struct datum_username_mod **umods_p, json_t *item, bool log_errors);
 struct datum_username_mod *datum_username_mods_next(struct datum_username_mod *prev_umod);
 struct datum_username_mod *datum_username_mods_find(struct datum_username_mod *umod, const char *modname, size_t modname_len);
 

src/datum_conf_tests.c

@@ -52,7 +52,7 @@ struct datum_test_username_mods {
 
 void datum_conf_test_parse_username_mods__(const unsigned int code_line, json_t * const j_input, const char * const input, const int expected_ret, const struct datum_test_username_mods *expected_umods) {
 	struct datum_username_mod *umods = NULL;
-	int ret = datum_config_parse_username_mods(&umods, j_input);
+	int ret = datum_config_parse_username_mods(&umods, j_input, false);
 	json_decref(j_input);
 	datum_test_(ret == expected_ret, input, code_line, "return value");
 	if (ret != 1) {

src/datum_stratum_tests.c

@@ -46,7 +46,7 @@ void datum_stratum_mod_username_tests() {
 	json_t * const j_umods = JSON_LOADS(s_umods, &err);
 	assert(j_umods);
 	struct datum_username_mod *umods = NULL;
-	int ret = datum_config_parse_username_mods(&umods, j_umods);
+	int ret = datum_config_parse_username_mods(&umods, j_umods, false);
 	assert(ret == 1);
 	json_decref(j_umods);
 	datum_config.stratum_username_mod = umods;