1 files changed, 134 insertions, 0 deletions
diff --git a/web/server/h2o/libh2o/include/h2o/http2_scheduler.h b/web/server/h2o/libh2o/include/h2o/http2_scheduler.h
new file mode 100644
index 00000000..f0a7d6e8
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+++ b/web/server/h2o/libh2o/include/h2o/http2_scheduler.h
@@ -0,0 +1,134 @@
+/*
+ * Copyright (c) 2015 DeNA Co., Ltd.
+ *
+ * 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 h2o__http2__scheduler_h
+#define h2o__http2__scheduler_h
+
+#include <assert.h>
+#include "h2o/linklist.h"
+#include "h2o/memory.h"
+
+typedef struct st_h2o_http2_scheduler_queue_node_t {
+    h2o_linklist_t _link;
+    size_t _deficit;
+} h2o_http2_scheduler_queue_node_t;
+
+typedef struct st_h2o_http2_scheduler_queue_t h2o_http2_scheduler_queue_t;
+
+/**
+ * resembles a node in the dependency tree; i.e. assigned for each HTTP/2 stream (as a member of openref), or the root of the tree
+ * associated to the connection
+ */
+typedef struct st_h2o_http2_scheduler_node_t {
+    struct st_h2o_http2_scheduler_node_t *_parent; /* NULL if root */
+    h2o_linklist_t _all_refs;                      /* list of nodes */
+    h2o_http2_scheduler_queue_t *_queue;           /* priority list (NULL if _all_refs is empty) */
+} h2o_http2_scheduler_node_t;
+
+/**
+ * the entry to be scheduled; is assigned for every HTTP/2 stream.
+ */
+typedef struct st_h2o_http2_scheduler_openref_t {
+    h2o_http2_scheduler_node_t node;
+    uint16_t weight;
+    h2o_linklist_t _all_link; /* linked to _all_refs */
+    size_t _active_cnt;       /* COUNT(active_streams_in_dependents) + _self_is_active */
+    int _self_is_active;
+    h2o_http2_scheduler_queue_node_t _queue_node;
+} h2o_http2_scheduler_openref_t;
+
+/**
+ * callback called by h2o_http2_scheduler_run.
+ * @param ref reference to an active stream that should consume resource
+ * @param still_is_active [out] flag to indicate whether the ref should still be marked as active after returning from the function
+ * @param cb_arg value of cb_arg passed to h2o_http2_scheduler_run
+ * @return non-zero value to stop traversing through the tree, or 0 to continue
+ */
+typedef int (*h2o_http2_scheduler_run_cb)(h2o_http2_scheduler_openref_t *ref, int *still_is_active, void *cb_arg);
+
+/**
+ *
+ */
+void h2o_http2_scheduler_init(h2o_http2_scheduler_node_t *root);
+
+/**
+ * disposes of the scheduler.  All open references belonging to the node must be closed before calling this functions.
+ */
+void h2o_http2_scheduler_dispose(h2o_http2_scheduler_node_t *root);
+/**
+ * opens a reference with given parent as its dependency
+ */
+void h2o_http2_scheduler_open(h2o_http2_scheduler_openref_t *ref, h2o_http2_scheduler_node_t *parent, uint16_t weight,
+                              int exclusive);
+/**
+ * closes a reference.  All the dependents are raised to become the dependents of the parent of the reference being closed.
+ */
+void h2o_http2_scheduler_close(h2o_http2_scheduler_openref_t *ref);
+/**
+ * reprioritizes the reference.
+ */
+void h2o_http2_scheduler_rebind(h2o_http2_scheduler_openref_t *ref, h2o_http2_scheduler_node_t *new_parent, uint16_t weight,
+                                int exclusive);
+/**
+ * tests if the ref is open
+ */
+static int h2o_http2_scheduler_is_open(h2o_http2_scheduler_openref_t *ref);
+/**
+ * returns weight associated to the reference
+ */
+static uint16_t h2o_http2_scheduler_get_weight(h2o_http2_scheduler_openref_t *ref);
+/**
+ * returns the parent
+ */
+static h2o_http2_scheduler_node_t *h2o_http2_scheduler_get_parent(h2o_http2_scheduler_openref_t *ref);
+/**
+ * activates a reference so that it would be passed back as the argument to the callback of the h2o_http2_scheduler_run function
+ * if any resource should be allocated
+ */
+void h2o_http2_scheduler_activate(h2o_http2_scheduler_openref_t *ref);
+/**
+ * calls the callback of the references linked to the dependency tree one by one, in the order defined by the dependency and the
+ * weight.
+ */
+int h2o_http2_scheduler_run(h2o_http2_scheduler_node_t *root, h2o_http2_scheduler_run_cb cb, void *cb_arg);
+/**
+ * returns if there are any active entries nodes in the scheduler (may have false positives, but no false negatives)
+ */
+int h2o_http2_scheduler_is_active(h2o_http2_scheduler_node_t *root);
+
+/* inline definitions */
+
+inline int h2o_http2_scheduler_is_open(h2o_http2_scheduler_openref_t *ref)
+{
+    return h2o_linklist_is_linked(&ref->_all_link);
+}
+
+inline uint16_t h2o_http2_scheduler_get_weight(h2o_http2_scheduler_openref_t *ref)
+{
+    return ref->weight;
+}
+
+inline h2o_http2_scheduler_node_t *h2o_http2_scheduler_get_parent(h2o_http2_scheduler_openref_t *ref)
+{
+    return ref->node._parent;
+}
+
+#endif