Fix: relayd: file rotation and live read

[lttng-tools.git] / src / bin / lttng-relayd / tracefile-array.h

diff --git a/src/bin/lttng-relayd/tracefile-array.h b/src/bin/lttng-relayd/tracefile-array.h
new file mode 100644 (file)
index 0000000..9158f4f
--- /dev/null
+++ b/src/bin/lttng-relayd/tracefile-array.h
@@ -0,0 +1,65 @@
+#ifndef _TRACEFILE_ARRAY_H
+#define _TRACEFILE_ARRAY_H
+
+/*
+ * Copyright (C) 2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License, version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 51
+ * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <limits.h>
+#include <inttypes.h>
+#include <pthread.h>
+#include <stdbool.h>
+
+struct tracefile {
+       /* Per-tracefile head/tail seq. */
+       uint64_t seq_head;      /* Newest seqcount. Inclusive. */
+       uint64_t seq_tail;      /* Oldest seqcount. Inclusive. */
+};
+
+/*
+ * Represents an array of trace files in a stream.
+ */
+struct tracefile_array {
+       struct tracefile *tf;
+       size_t count;
+
+       /* Current head/tail files. */
+       uint64_t file_head;
+       uint64_t file_tail;
+
+       /* Overall head/tail seq for the entire array. Inclusive. */
+       uint64_t seq_head;
+       uint64_t seq_tail;
+};
+
+struct tracefile_array *tracefile_array_create(size_t count);
+void tracefile_array_destroy(struct tracefile_array *tfa);
+
+void tracefile_array_file_rotate(struct tracefile_array *tfa);
+void tracefile_array_commit_seq(struct tracefile_array *tfa);
+
+uint64_t tracefile_array_get_file_index_head(struct tracefile_array *tfa);
+/* May return -1ULL in the case where we have not received any indexes yet. */
+uint64_t tracefile_array_get_seq_head(struct tracefile_array *tfa);
+
+uint64_t tracefile_array_get_file_index_tail(struct tracefile_array *tfa);
+/* May return -1ULL in the case where we have not received any indexes yet. */
+uint64_t tracefile_array_get_seq_tail(struct tracefile_array *tfa);
+
+bool tracefile_array_seq_in_file(struct tracefile_array *tfa,
+               uint64_t file_index, uint64_t seq);
+
+#endif /* _STREAM_H */