Remove //net (except for Android test stuff) and sdch

net/spdy/spdy_priority_tree.h

Index: net/spdy/spdy_priority_tree.h
diff --git a/net/spdy/spdy_priority_tree.h b/net/spdy/spdy_priority_tree.h
deleted file mode 100644
index c13268c516360dcec5fc5f7cc51797aae1c894a2..0000000000000000000000000000000000000000
--- a/net/spdy/spdy_priority_tree.h
+++ /dev/null
@@ -1,558 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef NET_SPDY_SPDY_PRIORITY_TREE_H_
-#define NET_SPDY_SPDY_PRIORITY_TREE_H_
-
-#include <cmath>
-#include <list>
-#include <map>
-#include <queue>
-#include <set>
-
-#include "base/basictypes.h"
-#include "base/containers/hash_tables.h"
-#include "base/logging.h"
-#include "base/memory/scoped_ptr.h"
-
-namespace net {
-
-// This data structure implements the HTTP2 prioritization data structure
-// defined in draft standard:
-// http://tools.ietf.org/html/draft-ietf-httpbis-http2-13
-//
-// Nodes can be added and removed, and dependencies between them defined.  Each
-// node can have at most one parent and at most one child (forming a list), but
-// there can be multiple lists, with each list root having its own priority.
-// Individual nodes can also be marked as ready to read/write, and then the
-// whole structure can be queried to pick the next node to read/write out of
-// those ready.
-//
-// The NodeId type must be a POD that supports comparison (most
-// likely, it will be a number).
-
-namespace test {
-template <typename NodeId>
-class SpdyPriorityTreePeer;
-}
-
-const int kRootNodeId = 0;
-const int kDefaultWeight = 16;
-const int kMinWeight = 1;
-const int kMaxWeight = 256;
-
-template <typename NodeId>
-class SpdyPriorityTree {
-  typedef std::vector<std::pair<NodeId, float> > PriorityNodeList;
-
- public:
-  SpdyPriorityTree();
-  ~SpdyPriorityTree();
-
-  typedef std::list<NodeId> List;
-  struct Node {
-    Node();
-    ~Node();
-
-    NodeId id;
-    NodeId parent_id;
-    int weight;  // Weights can range between 1 and 256 (inclusive).
-    // The total weight of this node's direct descendants.
-    int total_child_weights;
-    // The total weight of direct descendants that are writeable
-    // (ready to write and not blocked). This value does not necessarily
-    // reflect the current state of the tree; instead, we lazily update it
-    // on calls to PropagateNodeState(node.id).
-    int total_writeable_child_weights;
-    List* child_list;  // node ID's of children, if any
-    bool blocked;  // Is the associated stream write-blocked?
-    bool ready;  // Does the stream have data ready for writing?
-    float priority;  // The fraction of resources to dedicate to this node.
-  };
-
-  // Orders in descending order of priority.
-  struct NodePriorityComparator {
-    bool operator ()(const std::pair<NodeId, float>& lhs,
-                     const std::pair<NodeId, float>& rhs);
-  };
-
-  friend class test::SpdyPriorityTreePeer<NodeId>;
-
-  // Return the number of nodes currently in the tree.
-  int num_nodes() const;
-
-  // Return true if the tree contains a node with the given ID.
-  bool NodeExists(NodeId node_id) const;
-
-  // Add a new node with the given weight and parent. Non-exclusive nodes
-  // simply get added below the parent node. If exclusive = true, the node
-  // becomes the parent's sole child and the parent's previous children
-  // become the children of the new node.
-  // Returns true on success. Returns false if the node already exists
-  // in the tree, or if the parent node does not exist.
-  bool AddNode(NodeId node_id, NodeId parent_id, int weight, bool exclusive);
-
-  // Remove an existing node from the tree.  Returns true on success, or
-  // false if the node doesn't exist.
-  bool RemoveNode(NodeId node_id);
-
-  // Get the weight of the given node.
-  int GetWeight(NodeId node_id) const;
-
-  // Get the parent of the given node.  If the node doesn't exist, or is a root
-  // node (and thus has no parent), returns NodeId().
-  NodeId GetParent(NodeId node_id) const;
-
-  // Get the child list of the given node.  If the node doesn't exist, or has no
-  // child, returns NULL.
-  std::list<NodeId>* GetChildren(NodeId node_id) const;
-
-  // Set the priority of the given node.
-  bool SetWeight(NodeId node_id, int weight);
-
-  // Set the parent of the given node.  Returns true on success.
-  // Returns false and has no effect if the node and/or the parent doesn't
-  // exist. If the new parent is a descendant of the node (i.e. this would have
-  // created a cycle) then we rearrange the topology of the tree as described
-  // in the HTTP2 spec.
-  bool SetParent(NodeId node_id, NodeId parent_id, bool exclusive);
-
-  // Returns true if the node parent_id has child_id in its child_list.
-  bool HasChild(NodeId parent_id, NodeId child_id) const;
-
-  // Mark a node as blocked or unblocked. Return true on success, or false
-  // if unable to mark the specified node.
-  bool SetBlocked(NodeId node_id, bool blocked);
-
-  // Mark whether or not a node is ready to write; i.e. whether there is
-  // buffered data for the associated stream. Return true on success, or false
-  // if unable to mark the specified node.
-  bool SetReady(NodeId node_id, bool ready);
-
-  // Return true if all internal invariants hold (useful for unit tests).
-  // Unless there are bugs, this should always return true.
-  bool ValidateInvariantsForTests() const;
-
-  // Get the given node, or return NULL if it doesn't exist.
-  const Node* FindNode(NodeId node_id) const;
-
-  // Returns an ordered list of writeable nodes and their priorities.
-  // Priority is calculated as:
-  // parent's priority * (node's weight / sum of sibling weights)
-  PriorityNodeList GetPriorityList();
-
- protected:
-  // Update the value of total_writeable_child_weights for the given node
-  // to reflect the current state of the tree.
-  void PropagateNodeState(NodeId node);
-
- private:
-  typedef base::hash_map<NodeId, Node> NodeMap;
-
-  NodeMap all_nodes_;  // maps from node IDs to Node objects
-
-  DISALLOW_COPY_AND_ASSIGN(SpdyPriorityTree);
-};
-
-template <typename NodeId>
-SpdyPriorityTree<NodeId>::SpdyPriorityTree() {
-  Node* root_node = &all_nodes_[kRootNodeId];
-  root_node->id = kRootNodeId;
-  root_node->weight = kDefaultWeight;
-  root_node->parent_id = static_cast<NodeId>(kRootNodeId);
-  root_node->child_list = new std::list<NodeId>;
-  root_node->priority = 1.0;
-  root_node->ready = true;
-}
-
-template <typename NodeId>
-SpdyPriorityTree<NodeId>::~SpdyPriorityTree() {}
-
-template <typename NodeId>
-SpdyPriorityTree<NodeId>::Node::Node() :
-  parent_id(kRootNodeId),
-  weight(kDefaultWeight),
-  total_child_weights(0),
-  total_writeable_child_weights(0),
-  child_list(),
-  blocked(false),
-  ready(false),
-  priority(0) {
-}
-
-template <typename NodeId>
-SpdyPriorityTree<NodeId>::Node::~Node() {
-  delete child_list;
-}
-
-template <typename NodeId>
-bool SpdyPriorityTree<NodeId>::NodePriorityComparator::operator ()(
-    const std::pair<NodeId, float>& lhs,
-    const std::pair<NodeId, float>& rhs) {
-  return lhs.second > rhs.second;
-}
-
-template <typename NodeId>
-int SpdyPriorityTree<NodeId>::num_nodes() const {
-  return all_nodes_.size();
-}
-
-template <typename NodeId>
-bool SpdyPriorityTree<NodeId>::NodeExists(NodeId node_id) const {
-  return all_nodes_.count(node_id) != 0;
-}
-
-template <typename NodeId>
-bool SpdyPriorityTree<NodeId>::AddNode(NodeId node_id,
-                                       NodeId parent_id,
-                                       int weight,
-                                       bool exclusive) {
-  if (NodeExists(node_id) || !NodeExists(parent_id)) {
-    return false;
-  }
-  if (weight < kMinWeight || weight > kMaxWeight) {
-    return false;
-  }
-  Node* parent = &all_nodes_[parent_id];
-  Node* new_node = &all_nodes_[node_id];
-  new_node->id = node_id;
-  new_node->weight = weight;
-  new_node->parent_id = parent_id;
-  if (exclusive) {
-    // Move the parent's current children below the new node.
-    new_node->child_list = parent->child_list;
-    new_node->total_child_weights = parent->total_child_weights;
-    // Update each child's parent_id.
-    for (typename List::iterator it = new_node->child_list->begin();
-         it != new_node->child_list->end(); ++it) {
-      Node* child = &all_nodes_[*it];
-      child->parent_id = node_id;
-    }
-    // Clear parent's old child data.
-    parent->child_list = new std::list<NodeId>;
-    parent->total_child_weights = 0;
-  } else {
-    new_node->child_list = new std::list<NodeId>;
-  }
-  // Add new node to parent.
-  parent->child_list->push_back(node_id);
-  parent->total_child_weights += weight;
-  return true;
-}
-
-template <typename NodeId>
-bool SpdyPriorityTree<NodeId>::RemoveNode(NodeId node_id) {
-  if (node_id == static_cast<NodeId>(kRootNodeId) || !NodeExists(node_id)) {
-    return false;
-  }
-  const Node& node = all_nodes_[node_id];
-
-  DCHECK(NodeExists(node.parent_id));
-  Node* parent = &all_nodes_[node.parent_id];
-  // Remove the node id from parent's child list.
-  parent->child_list->remove(node_id);
-  parent->total_child_weights -= node.weight;
-
-  // Move the node's children to the parent's child list.
-  if (node.child_list != NULL) {
-    // Update each child's parent_id and weight.
-    for (typename List::iterator it = node.child_list->begin();
-         it != node.child_list->end(); ++it) {
-      Node* child = &all_nodes_[*it];
-      child->parent_id = node.parent_id;
-      // Divide the removed node's weight among its children, rounding to the
-      // nearest valid weight.
-      float float_weight =  node.weight * static_cast<float>(child->weight) /
-                            static_cast<float>(node.total_child_weights);
-      int new_weight = std::floor(float_weight + 0.5);
-      if (new_weight == 0) {
-        new_weight = 1;
-      }
-      child->weight = new_weight;
-      parent->total_child_weights += child->weight;
-    }
-    parent->child_list->splice(parent->child_list->end(), *node.child_list);
-  }
-
-  // Delete the node.
-  all_nodes_.erase(node_id);
-  return true;
-}
-
-template <typename NodeId>
-int SpdyPriorityTree<NodeId>::GetWeight(NodeId node_id) const {
-  const Node* node = FindNode(node_id);
-  if (node != NULL) {
-    return node->weight;
-  }
-  return 0;
-}
-
-template <typename NodeId>
-NodeId SpdyPriorityTree<NodeId>::GetParent(NodeId node_id) const {
-  const Node* node = FindNode(node_id);
-  if (node != NULL && node->id != static_cast<NodeId>(kRootNodeId)) {
-    return node->parent_id;
-  }
-  return static_cast<NodeId>(kRootNodeId);
-}
-
-template <typename NodeId>
-std::list<NodeId>* SpdyPriorityTree<NodeId>::GetChildren(NodeId node_id) const {
-  const Node* node = FindNode(node_id);
-  if (node != NULL) {
-    return node->child_list;
-  }
-  return NULL;
-}
-
-template <typename NodeId>
-bool SpdyPriorityTree<NodeId>::SetWeight(
-    NodeId node_id, int weight) {
-  if (!NodeExists(node_id)) {
-    return false;
-  }
-  if (weight < kMinWeight || weight > kMaxWeight) {
-    return false;
-  }
-
-  Node* node = &all_nodes_[node_id];
-  Node* parent = &all_nodes_[node->parent_id];
-
-  parent->total_child_weights += (weight - node->weight);
-  node->weight = weight;
-
-  return true;
-}
-
-
-template <typename NodeId>
-bool SpdyPriorityTree<NodeId>::SetParent(
-    NodeId node_id, NodeId parent_id, bool exclusive) {
-  if (!NodeExists(node_id) || !NodeExists(parent_id)) {
-    return false;
-  }
-  if (node_id == parent_id) return false;
-
-  Node* node = &all_nodes_[node_id];
-  Node* new_parent = &all_nodes_[parent_id];
-  // If the new parent is already the node's parent, we're done.
-  if (node->parent_id == parent_id) {
-    return true;
-  }
-
-  // Next, check to see if the new parent is currently a descendant
-  // of the node.
-  Node* last = new_parent;
-  NodeId last_id = parent_id;
-  bool cycle_exists = false;
-  while (last->parent_id != static_cast<NodeId>(kRootNodeId)) {
-    if (last->parent_id == node_id) {
-      cycle_exists = true;
-      break;
-    }
-    last_id = last->parent_id;
-    DCHECK(NodeExists(last_id));
-    last = &all_nodes_[last_id];
-  }
-
-  if (cycle_exists) {
-    // The new parent moves to the level of the current node.
-    SetParent(parent_id, node->parent_id, false);
-  }
-
-  // Remove node from old parent's child list.
-  const NodeId old_parent_id = node->parent_id;
-  DCHECK(NodeExists(old_parent_id));
-  Node* old_parent = &all_nodes_[old_parent_id];
-  old_parent->child_list->remove(node_id);
-  old_parent->total_child_weights -= node->weight;
-
-  // Make the change.
-  node->parent_id = parent_id;
-  new_parent->child_list->push_back(node_id);
-  new_parent->total_child_weights += node->weight;
-  return true;
-}
-
-template <typename NodeId>
-bool SpdyPriorityTree<NodeId>::SetBlocked(NodeId node_id, bool blocked) {
-  if (!NodeExists(node_id)) {
-    return false;
-  }
-
-  Node* node = &all_nodes_[node_id];
-  node->blocked = blocked;
-  return true;
-}
-
-template <typename NodeId>
-bool SpdyPriorityTree<NodeId>::SetReady(NodeId node_id, bool ready) {
-  if (!NodeExists(node_id)) {
-    return false;
-  }
-  Node* node = &all_nodes_[node_id];
-  node->ready = ready;
-  return true;
-}
-
-template <typename NodeId>
-void SpdyPriorityTree<NodeId>::PropagateNodeState(NodeId node_id) {
-  // Reset total_writeable_child_weights to its maximum value.
-  Node* node = &all_nodes_[node_id];
-  node->total_writeable_child_weights = node->total_child_weights;
-  for (typename List::iterator it = node->child_list->begin();
-       it != node->child_list->end(); ++it) {
-    PropagateNodeState(*it);
-  }
-  if (node->total_writeable_child_weights == 0 &&
-      (node->blocked || !node->ready)) {
-    // Tell the parent that this entire subtree is unwriteable.
-    Node* parent = &all_nodes_[node->parent_id];
-    parent->total_writeable_child_weights -= node->weight;
-  }
-}
-
-template <typename NodeId>
-const typename SpdyPriorityTree<NodeId>::Node*
-SpdyPriorityTree<NodeId>::FindNode(NodeId node_id) const {
-  typename NodeMap::const_iterator iter = all_nodes_.find(node_id);
-  if (iter == all_nodes_.end()) {
-    return NULL;
-  }
-  return &iter->second;
-}
-
-template <typename NodeId>
-bool SpdyPriorityTree<NodeId>::HasChild(NodeId parent_id,
-                                        NodeId child_id) const {
-  const Node* parent = FindNode(parent_id);
-  return parent->child_list->end() !=
-         std::find(parent->child_list->begin(),
-                   parent->child_list->end(),
-                   child_id);
-}
-
-template <typename NodeId>
-std::vector<std::pair<NodeId, float> >
-SpdyPriorityTree<NodeId>::GetPriorityList() {
-  typedef std::pair<NodeId, float> PriorityNode;
-  typedef std::vector<PriorityNode> PriorityList;
-  PriorityList priority_list;
-
-  // Update total_writeable_child_weights to reflect the current
-  // state of the tree.
-  PropagateNodeState(kRootNodeId);
-
-  List queue;
-  const Node* root_node = FindNode(kRootNodeId);
-  DCHECK(root_node->priority == 1.0);
-  // Start by examining our top-level nodes.
-  for (typename List::iterator it = root_node->child_list->begin();
-       it != root_node->child_list->end(); ++it) {
-    queue.push_back(*it);
-  }
-  while (!queue.empty()) {
-    NodeId current_node_id = queue.front();
-    Node* current_node = &all_nodes_[current_node_id];
-    const Node* parent_node = FindNode(current_node->parent_id);
-    if (current_node->blocked || !current_node->ready) {
-      if (current_node->total_writeable_child_weights > 0) {
-        // This node isn't writeable, but it has writeable children.
-        // Calculate the total fraction of resources we can allot
-        // to this subtree.
-        current_node->priority = parent_node->priority *
-            (static_cast<float>(current_node->weight) /
-             static_cast<float>(parent_node->total_writeable_child_weights));
-        // Examine the children.
-        for (typename List::iterator it = current_node->child_list->begin();
-             it != current_node->child_list->end(); ++it) {
-          queue.push_back(*it);
-        }
-      } else {
-        // There's nothing to see in this subtree.
-        current_node->priority = 0;
-      }
-    } else {
-      // This node is writeable; calculate its priority.
-      current_node->priority = parent_node->priority *
-          (static_cast<float>(current_node->weight) /
-           static_cast<float>(parent_node->total_writeable_child_weights));
-      // Add this node to the priority list.
-      priority_list.push_back(PriorityNode(current_node_id,
-                                           current_node->priority));
-    }
-    // Remove this node from the queue.
-    queue.pop_front();
-  }
-
-  // Sort the nodes in descending order of priority.
-  std::sort(priority_list.begin(), priority_list.end(),
-            NodePriorityComparator());
-
-  return priority_list;
-}
-
-template <typename NodeId>
-bool SpdyPriorityTree<NodeId>::ValidateInvariantsForTests() const {
-  int total_nodes = 0;
-  int nodes_visited = 0;
-  // Iterate through all nodes in the map.
-  for (typename NodeMap::const_iterator iter = all_nodes_.begin();
-       iter != all_nodes_.end(); ++iter) {
-    ++total_nodes;
-    ++nodes_visited;
-    const Node& node = iter->second;
-    // All nodes except the root should have a parent, and should appear in
-    // the child_list of that parent.
-    if (node.id != static_cast<NodeId>(kRootNodeId) &&
-        (!NodeExists(node.parent_id) ||
-         !HasChild(node.parent_id, node.id))) {
-      DLOG(INFO) << "Parent node " << node.parent_id
-                 << " does not exist, or does not list node " << node.id
-                 << " as its child.";
-      return false;
-    }
-
-    if (!node.child_list->empty()) {
-      int total_child_weights = 0;
-      // Iterate through the node's children.
-      for (typename List::iterator it = node.child_list->begin();
-           it != node.child_list->end(); ++it) {
-        ++nodes_visited;
-        // Each node in the list should exist and should have this node
-        // set as its parent.
-        if (!NodeExists(*it) || node.id != GetParent(*it)) {
-          DLOG(INFO) << "Child node " << *it << " does not exist, "
-                     << "or does not list " << node.id << " as its parent.";
-          return false;
-        }
-        const Node* child = FindNode(*it);
-        total_child_weights += child->weight;
-      }
-      // Verify that total_child_weights is correct.
-      if (total_child_weights != node.total_child_weights) {
-        DLOG(INFO) << "Child weight totals do not agree. For node " << node.id
-                   << " total_child_weights has value "
-                   << node.total_child_weights
-                   << ", expected " << total_child_weights;
-        return false;
-      }
-    }
-  }
-
-  // Make sure num_nodes reflects the total number of nodes the map contains.
-  if (total_nodes != num_nodes()) {
-    DLOG(INFO) << "Map contains incorrect number of nodes.";
-    return false;
-  }
-  // Validate the validation function; we should have visited each node twice
-  // (except for the root)
-  DCHECK(nodes_visited == 2*num_nodes() - 1);
-  return true;
-}
-
-}  // namespace net
-
-#endif  // NET_SPDY_SPDY_PRIORITY_TREE_H_