github.com/maruel/nin@v0.0.0-20220112143044-f35891e3ce7e/src/state.h (about)

     1  // Copyright 2011 Google Inc. All Rights Reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  #ifndef NINJA_STATE_H_
    16  #define NINJA_STATE_H_
    17  
    18  #include <map>
    19  #include <set>
    20  #include <string>
    21  #include <vector>
    22  
    23  #include "eval_env.h"
    24  #include "graph.h"
    25  #include "hash_map.h"
    26  #include "util.h"
    27  
    28  struct Edge;
    29  struct Node;
    30  struct Rule;
    31  
    32  /// A pool for delayed edges.
    33  /// Pools are scoped to a State. Edges within a State will share Pools. A Pool
    34  /// will keep a count of the total 'weight' of the currently scheduled edges. If
    35  /// a Plan attempts to schedule an Edge which would cause the total weight to
    36  /// exceed the depth of the Pool, the Pool will enqueue the Edge instead of
    37  /// allowing the Plan to schedule it. The Pool will relinquish queued Edges when
    38  /// the total scheduled weight diminishes enough (i.e. when a scheduled edge
    39  /// completes).
    40  struct Pool {
    41    Pool(const std::string& name, int depth)
    42      : name_(name), current_use_(0), depth_(depth), delayed_() {}
    43  
    44    // A depth of 0 is infinite
    45    bool is_valid() const { return depth_ >= 0; }
    46    int depth() const { return depth_; }
    47    const std::string& name() const { return name_; }
    48    int current_use() const { return current_use_; }
    49  
    50    /// true if the Pool might delay this edge
    51    bool ShouldDelayEdge() const { return depth_ != 0; }
    52  
    53    /// informs this Pool that the given edge is committed to be run.
    54    /// Pool will count this edge as using resources from this pool.
    55    void EdgeScheduled(const Edge& edge);
    56  
    57    /// informs this Pool that the given edge is no longer runnable, and should
    58    /// relinquish its resources back to the pool
    59    void EdgeFinished(const Edge& edge);
    60  
    61    /// adds the given edge to this Pool to be delayed.
    62    void DelayEdge(Edge* edge);
    63  
    64    /// Pool will add zero or more edges to the ready_queue
    65    void RetrieveReadyEdges(EdgeSet* ready_queue);
    66  
    67    /// Dump the Pool and its edges (useful for debugging).
    68    void Dump() const;
    69  
    70   private:
    71    std::string name_;
    72  
    73    /// |current_use_| is the total of the weights of the edges which are
    74    /// currently scheduled in the Plan (i.e. the edges in Plan::ready_).
    75    int current_use_;
    76    int depth_;
    77  
    78    struct WeightedEdgeCmp {
    79      bool operator()(const Edge* a, const Edge* b) const {
    80        if (!a) return b;
    81        if (!b) return false;
    82        int weight_diff = a->weight() - b->weight();
    83        return ((weight_diff < 0) || (weight_diff == 0 && EdgeCmp()(a, b)));
    84      }
    85    };
    86  
    87    typedef std::set<Edge*, WeightedEdgeCmp> DelayedEdges;
    88    DelayedEdges delayed_;
    89  };
    90  
    91  /// Global state (file status) for a single run.
    92  struct State {
    93    static Pool kDefaultPool;
    94    static Pool kConsolePool;
    95    static const Rule kPhonyRule;
    96  
    97    State();
    98  
    99    void AddPool(Pool* pool);
   100    Pool* LookupPool(const std::string& pool_name);
   101  
   102    Edge* AddEdge(const Rule* rule);
   103  
   104    Node* GetNode(StringPiece path, uint64_t slash_bits);
   105    Node* LookupNode(StringPiece path) const;
   106    Node* SpellcheckNode(const std::string& path);
   107  
   108    void AddIn(Edge* edge, StringPiece path, uint64_t slash_bits);
   109    bool AddOut(Edge* edge, StringPiece path, uint64_t slash_bits);
   110    void AddValidation(Edge* edge, StringPiece path, uint64_t slash_bits);
   111    bool AddDefault(StringPiece path, std::string* error);
   112  
   113    /// Reset state.  Keeps all nodes and edges, but restores them to the
   114    /// state where we haven't yet examined the disk for dirty state.
   115    void Reset();
   116  
   117    /// Dump the nodes and Pools (useful for debugging).
   118    void Dump();
   119  
   120    /// @return the root node(s) of the graph. (Root nodes have no output edges).
   121    /// @param error where to write the error message if somethings went wrong.
   122    std::vector<Node*> RootNodes(std::string* error) const;
   123    std::vector<Node*> DefaultNodes(std::string* error) const;
   124  
   125    /// Mapping of path -> Node.
   126    typedef ExternalStringHashMap<Node*>::Type Paths;
   127    Paths paths_;
   128  
   129    /// All the pools used in the graph.
   130    std::map<std::string, Pool*> pools_;
   131  
   132    /// All the edges of the graph.
   133    std::vector<Edge*> edges_;
   134  
   135    BindingEnv bindings_;
   136    std::vector<Node*> defaults_;
   137  };
   138  
   139  #endif  // NINJA_STATE_H_