1 files changed, 123 insertions, 0 deletions
diff --git a/src/shrpx_rate_limit.cc b/src/shrpx_rate_limit.cc
new file mode 100644
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--- /dev/null
+++ b/src/shrpx_rate_limit.cc
@@ -0,0 +1,123 @@
+/*
+ * nghttp2 - HTTP/2 C Library
+ *
+ * Copyright (c) 2015 Tatsuhiro Tsujikawa
+ *
+ * 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.
+ */
+#include "shrpx_rate_limit.h"
+
+#include <limits>
+
+#include "shrpx_connection.h"
+#include "shrpx_log.h"
+
+namespace shrpx {
+
+namespace {
+void regencb(struct ev_loop *loop, ev_timer *w, int revents) {
+  auto r = static_cast<RateLimit *>(w->data);
+  r->regen();
+}
+} // namespace
+
+RateLimit::RateLimit(struct ev_loop *loop, ev_io *w, size_t rate, size_t burst,
+                     Connection *conn)
+    : w_(w),
+      loop_(loop),
+      conn_(conn),
+      rate_(rate),
+      burst_(burst),
+      avail_(burst),
+      startw_req_(false) {
+  ev_timer_init(&t_, regencb, 0., 1.);
+  t_.data = this;
+  if (rate_ > 0) {
+    ev_timer_again(loop_, &t_);
+  }
+}
+
+RateLimit::~RateLimit() { ev_timer_stop(loop_, &t_); }
+
+size_t RateLimit::avail() const {
+  if (rate_ == 0) {
+    return std::numeric_limits<ssize_t>::max();
+  }
+  return avail_;
+}
+
+void RateLimit::drain(size_t n) {
+  if (rate_ == 0) {
+    return;
+  }
+  n = std::min(avail_, n);
+  avail_ -= n;
+  if (avail_ == 0) {
+    ev_io_stop(loop_, w_);
+  }
+}
+
+void RateLimit::regen() {
+  if (rate_ == 0) {
+    return;
+  }
+  if (avail_ + rate_ > burst_) {
+    avail_ = burst_;
+  } else {
+    avail_ += rate_;
+  }
+
+  if (w_->fd >= 0 && avail_ > 0 && startw_req_) {
+    ev_io_start(loop_, w_);
+    handle_tls_pending_read();
+  }
+}
+
+void RateLimit::startw() {
+  if (w_->fd < 0) {
+    return;
+  }
+  startw_req_ = true;
+  if (rate_ == 0 || avail_ > 0) {
+    ev_io_start(loop_, w_);
+    handle_tls_pending_read();
+    return;
+  }
+}
+
+void RateLimit::stopw() {
+  startw_req_ = false;
+  ev_io_stop(loop_, w_);
+}
+
+void RateLimit::handle_tls_pending_read() {
+  if (!conn_ || !conn_->tls.ssl ||
+      (SSL_pending(conn_->tls.ssl) == 0 && conn_->tls.rbuf.rleft() == 0 &&
+       (!conn_->tls.initial_handshake_done ||
+        conn_->tls.earlybuf.rleft() == 0))) {
+    return;
+  }
+
+  // Note that ev_feed_event works without starting watcher, but we
+  // only call this function if watcher is active.
+  ev_feed_event(loop_, w_, EV_READ);
+}
+
+} // namespace shrpx