1 files changed, 80 insertions, 0 deletions
diff --git a/lib/ngtcp2_range.h b/lib/ngtcp2_range.h
new file mode 100644
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+++ b/lib/ngtcp2_range.h
@@ -0,0 +1,80 @@
+/*
+ * 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_RANGE_H
+#define NGTCP2_RANGE_H
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif /* HAVE_CONFIG_H */
+
+#include <ngtcp2/ngtcp2.h>
+
+/*
+ * ngtcp2_range represents half-closed range [begin, end).
+ */
+typedef struct ngtcp2_range {
+  uint64_t begin;
+  uint64_t end;
+} ngtcp2_range;
+
+/*
+ * ngtcp2_range_init initializes |r| with the range [|begin|, |end|).
+ */
+void ngtcp2_range_init(ngtcp2_range *r, uint64_t begin, uint64_t end);
+
+/*
+ * ngtcp2_range_intersect returns the intersection of |a| and |b|.  If
+ * they do not overlap, it returns empty range.
+ */
+ngtcp2_range ngtcp2_range_intersect(const ngtcp2_range *a,
+                                    const ngtcp2_range *b);
+
+/*
+ * ngtcp2_range_len returns the length of |r|.
+ */
+uint64_t ngtcp2_range_len(const ngtcp2_range *r);
+
+/*
+ * ngtcp2_range_eq returns nonzero if |a| equals |b|, such that
+ * a->begin == b->begin, and a->end == b->end hold.
+ */
+int ngtcp2_range_eq(const ngtcp2_range *a, const ngtcp2_range *b);
+
+/*
+ * ngtcp2_range_cut returns the left and right range after removing
+ * |b| from |a|.  This function assumes that |a| completely includes
+ * |b|.  In other words, a->begin <= b->begin and b->end <= a->end
+ * hold.
+ */
+void ngtcp2_range_cut(ngtcp2_range *left, ngtcp2_range *right,
+                      const ngtcp2_range *a, const ngtcp2_range *b);
+
+/*
+ * ngtcp2_range_not_after returns nonzero if the right edge of |a|
+ * does not go beyond of the right edge of |b|.
+ */
+int ngtcp2_range_not_after(const ngtcp2_range *a, const ngtcp2_range *b);
+
+#endif /* NGTCP2_RANGE_H */