X-Git-Url: https://git.efficios.com/?a=blobdiff_plain;f=src%2Fcommon%2Findex-allocator.hpp;fp=src%2Fcommon%2Findex-allocator.hpp;h=ee7c2ec758dd5dd707780b9a42ae5d3c0d4fab6c;hb=7532fa3bd22e403958f46cd35c824f490d93292d;hp=0000000000000000000000000000000000000000;hpb=985aea182b618c85c51651f224abedfe367c75ee;p=deliverable%2Flttng-tools.git

diff --git a/src/common/index-allocator.hpp b/src/common/index-allocator.hpp
new file mode 100644
index 000000000..ee7c2ec75
--- /dev/null
+++ b/src/common/index-allocator.hpp
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2020 Francis Deslauriers <francis.deslauriers@efficios.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ *
+ */
+
+#ifndef _COMMON_INDEX_ALLOCATOR_H
+#define _COMMON_INDEX_ALLOCATOR_H
+
+#include <inttypes.h>
+#include <lttng/lttng-export.h>
+
+struct lttng_index_allocator;
+
+enum lttng_index_allocator_status {
+	LTTNG_INDEX_ALLOCATOR_STATUS_OK,
+	LTTNG_INDEX_ALLOCATOR_STATUS_EMPTY,
+	LTTNG_INDEX_ALLOCATOR_STATUS_ERROR,
+};
+
+/*
+ * Create an index allocator of `index_count` slots.
+ */
+extern "C" LTTNG_EXPORT
+struct lttng_index_allocator *lttng_index_allocator_create(
+		uint64_t index_count);
+
+/*
+ * Get the number of indexes currently in use.
+ */
+extern "C" LTTNG_EXPORT
+uint64_t lttng_index_allocator_get_index_count(
+	struct lttng_index_allocator *allocator);
+
+/*
+ * Allocate (i.e. reserve) a slot.
+ */
+extern "C" LTTNG_EXPORT
+enum lttng_index_allocator_status lttng_index_allocator_alloc(
+		struct lttng_index_allocator *allocator,
+		uint64_t *index);
+
+/*
+ * Release a slot by index. The slot will be re-used by the index allocator
+ * in future 'alloc' calls.
+ */
+extern "C" LTTNG_EXPORT
+enum lttng_index_allocator_status lttng_index_allocator_release(
+		struct lttng_index_allocator *allocator, uint64_t index);
+
+/*
+ * Destroy an index allocator.
+ */
+extern "C" LTTNG_EXPORT
+void lttng_index_allocator_destroy(struct lttng_index_allocator *allocator);
+
+#endif /* _COMMON_INDEX_ALLOCATOR_H */