lttng-ctl: Introduce lttng_log_level_rule

[lttng-tools.git] / include / lttng / log-level-rule.h

diff --git a/include/lttng/log-level-rule.h b/include/lttng/log-level-rule.h
new file mode 100644 (file)
index 0000000..ea9045d
--- /dev/null
+++ b/include/lttng/log-level-rule.h
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2020 Jonathan Rajotte <jonathan.rajotte-julien@efficios.com>
+ *
+ * SPDX-License-Identifier: LGPL-2.1-only
+ *
+ */
+
+#ifndef LTTNG_LOG_LEVEL_RULE_H
+#define LTTNG_LOG_LEVEL_RULE_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct lttng_log_level_rule;
+
+enum lttng_log_level_rule_type {
+       LTTNG_LOG_LEVEL_RULE_TYPE_UNKNOWN = -1,
+       LTTNG_LOG_LEVEL_RULE_TYPE_EXACTLY = 0,
+       LTTNG_LOG_LEVEL_RULE_TYPE_AT_LEAST_AS_SEVERE_AS = 1,
+};
+
+enum lttng_log_level_rule_status {
+       LTTNG_LOG_LEVEL_RULE_STATUS_OK = 0,
+       LTTNG_LOG_LEVEL_RULE_STATUS_ERROR = -1,
+       LTTNG_LOG_LEVEL_RULE_STATUS_INVALID = -3,
+};
+
+/*
+ * Returns the type of the log level rule `rule`, or:
+ *
+ * `LTTNG_LOG_LEVEL_RULE_TYPE_UNKNOWN`:
+ *     `rule` is `NULL`.
+ */
+extern enum lttng_log_level_rule_type lttng_log_level_rule_get_type(
+               const struct lttng_log_level_rule *rule);
+
+/*
+ * Creates a log level rule for which a log level must match exactly `level` to
+ * be considered.
+ *
+ * Returns `NULL` if:
+ *
+ * * There's a memory error.
+ *
+ * The returned log level rule must be destroyed using
+ * lttng_log_level_rule_destroy().
+ */
+extern struct lttng_log_level_rule *lttng_log_level_rule_exactly_create(
+               int level);
+
+/*
+ * Sets `level` to the level of the "exactly" log level rule `rule`.
+ *
+ * Returns:
+ *
+ * `LTTNG_LOG_LEVEL_RULE_STATUS_OK`:
+ *     Success.
+ *
+ * `LTTNG_LOG_LEVEL_RULE_STATUS_INVALID`:
+ *     * `rule` is NULL.
+ *     * `level` is NULL.
+ *     * The type of `rule` is not `LTTNG_LOG_LEVEL_RULE_TYPE_EXACTLY`.
+ */
+extern enum lttng_log_level_rule_status lttng_log_level_rule_exactly_get_level(
+               const struct lttng_log_level_rule *rule, int *level);
+
+/*
+ * Creates a log level rule for which a log level must be at least as severe as
+ * `level` to be considered.
+ *
+ * Returns `NULL` if:
+ *
+ * * There's a memory error.
+ *
+ * The returned log level rule must be destroyed using
+ * lttng_log_level_rule_destroy().
+ */
+extern struct lttng_log_level_rule *
+lttng_log_level_rule_at_least_as_severe_as_create(int level);
+
+/*
+ * Sets `level` to the level of the "at least as severe as" log level rule
+ * `rule`.
+ *
+ * Returns:
+ *
+ * `LTTNG_LOG_LEVEL_RULE_STATUS_OK`:
+ *     Success.
+ *
+ * `LTTNG_LOG_LEVEL_RULE_STATUS_INVALID`:
+ *     * `rule` is NULL.
+ *     * `level` is NULL.
+ *     * The type of `rule` is not
+ *       `LTTNG_LOG_LEVEL_RULE_TYPE_AT_LEAST_AS_SEVERE_AS`.
+ */
+extern enum lttng_log_level_rule_status
+lttng_log_level_rule_at_least_as_severe_as_get_level(
+               const struct lttng_log_level_rule *rule, int *level);
+
+/*
+ * Destroy the log level rule `log_level_rule` if not `NULL`.
+ */
+extern void lttng_log_level_rule_destroy(
+               struct lttng_log_level_rule *log_level_rule);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* LTTNG_LOG_LEVEL_RULE_H */