1 files changed, 57 insertions, 0 deletions
diff --git a/lib/nghttp2_ratelim.h b/lib/nghttp2_ratelim.h
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+++ b/lib/nghttp2_ratelim.h
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+/*
+ * nghttp2 - HTTP/2 C Library
+ *
+ * Copyright (c) 2023 nghttp2 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 NGHTTP2_RATELIM_H
+#define NGHTTP2_RATELIM_H
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif /* HAVE_CONFIG_H */
+
+#include <nghttp2/nghttp2.h>
+
+typedef struct nghttp2_ratelim {
+  /* burst is the maximum value of val. */
+  uint64_t burst;
+  /* rate is the amount of value that is regenerated per 1 tstamp. */
+  uint64_t rate;
+  /* val is the amount of value available to drain. */
+  uint64_t val;
+  /* tstamp is the last timestamp in second resolution that is known
+     to this object. */
+  uint64_t tstamp;
+} nghttp2_ratelim;
+
+/* nghttp2_ratelim_init initializes |rl| with the given parameters. */
+void nghttp2_ratelim_init(nghttp2_ratelim *rl, uint64_t burst, uint64_t rate);
+
+/* nghttp2_ratelim_update updates rl->val with the current |tstamp|
+   given in second resolution. */
+void nghttp2_ratelim_update(nghttp2_ratelim *rl, uint64_t tstamp);
+
+/* nghttp2_ratelim_drain drains |n| from rl->val.  It returns 0 if it
+   succeeds, or -1. */
+int nghttp2_ratelim_drain(nghttp2_ratelim *rl, uint64_t n);
+
+#endif /* NGHTTP2_RATELIM_H */