1 files changed, 89 insertions, 0 deletions
diff --git a/lib/ngtcp2_idtr.h b/lib/ngtcp2_idtr.h
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+++ b/lib/ngtcp2_idtr.h
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+/*
+ * ngtcp2
+ *
+ * Copyright (c) 2017 ngtcp2 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#ifndef NGTCP2_IDTR_H
+#define NGTCP2_IDTR_H
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif /* HAVE_CONFIG_H */
+
+#include <ngtcp2/ngtcp2.h>
+
+#include "ngtcp2_mem.h"
+#include "ngtcp2_gaptr.h"
+
+/*
+ * ngtcp2_idtr tracks the usage of stream ID.
+ */
+typedef struct ngtcp2_idtr {
+  /* gap maintains the range of ID which is not used yet. Initially,
+     its range is [0, UINT64_MAX). */
+  ngtcp2_gaptr gap;
+  /* server is nonzero if this object records server initiated stream
+     ID. */
+  int server;
+} ngtcp2_idtr;
+
+/*
+ * ngtcp2_idtr_init initializes |idtr|.
+ *
+ * If this object records server initiated ID (even number), set
+ * |server| to nonzero.
+ */
+void ngtcp2_idtr_init(ngtcp2_idtr *idtr, int server, const ngtcp2_mem *mem);
+
+/*
+ * ngtcp2_idtr_free frees resources allocated for |idtr|.
+ */
+void ngtcp2_idtr_free(ngtcp2_idtr *idtr);
+
+/*
+ * ngtcp2_idtr_open claims that |stream_id| is in used.
+ *
+ * It returns 0 if it succeeds, or one of the following negative error
+ * codes:
+ *
+ * NGTCP2_ERR_STREAM_IN_USE
+ *     ID has already been used.
+ * NGTCP2_ERR_NOMEM
+ *     Out of memory.
+ */
+int ngtcp2_idtr_open(ngtcp2_idtr *idtr, int64_t stream_id);
+
+/*
+ * ngtcp2_idtr_open tells whether ID |stream_id| is in used or not.
+ *
+ * It returns nonzero if |stream_id| is used.
+ */
+int ngtcp2_idtr_is_open(ngtcp2_idtr *idtr, int64_t stream_id);
+
+/*
+ * ngtcp2_idtr_first_gap returns the first id of first gap.  If there
+ * is no gap, it returns UINT64_MAX.  The returned id is an id space
+ * used in this object internally, and not stream ID.
+ */
+uint64_t ngtcp2_idtr_first_gap(ngtcp2_idtr *idtr);
+
+#endif /* NGTCP2_IDTR_H */