1 // Copyright 2011 Google Inc. All Rights Reserved.
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
7 // http://www.apache.org/licenses/LICENSE-2.0
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.
15 #ifndef NINJA_GRAPH_H_
16 #define NINJA_GRAPH_H_
23 #include "timestamp.h"
33 /// Information about a node in the dependency graph: the file, whether
34 /// it's dirty, mtime, etc.
36 Node(const string& path, unsigned int slash_bits)
38 slash_bits_(slash_bits),
44 /// Return false on error.
45 bool Stat(DiskInterface* disk_interface, string* err);
47 /// Return false on error.
48 bool StatIfNecessary(DiskInterface* disk_interface, string* err) {
51 return Stat(disk_interface, err);
54 /// Mark as not-yet-stat()ed and not dirty.
60 /// Mark the Node as already-stat()ed and missing.
69 bool status_known() const {
73 const string& path() const { return path_; }
74 /// Get |path()| but use slash_bits to convert back to original slash styles.
75 string PathDecanonicalized() const {
76 return PathDecanonicalized(path_, slash_bits_);
78 static string PathDecanonicalized(const string& path,
79 unsigned int slash_bits);
80 unsigned int slash_bits() const { return slash_bits_; }
82 TimeStamp mtime() const { return mtime_; }
84 bool dirty() const { return dirty_; }
85 void set_dirty(bool dirty) { dirty_ = dirty; }
86 void MarkDirty() { dirty_ = true; }
88 Edge* in_edge() const { return in_edge_; }
89 void set_in_edge(Edge* edge) { in_edge_ = edge; }
91 int id() const { return id_; }
92 void set_id(int id) { id_ = id; }
94 const vector<Edge*>& out_edges() const { return out_edges_; }
95 void AddOutEdge(Edge* edge) { out_edges_.push_back(edge); }
97 void Dump(const char* prefix="") const;
102 /// Set bits starting from lowest for backslashes that were normalized to
103 /// forward slashes by CanonicalizePath. See |PathDecanonicalized|.
104 unsigned int slash_bits_;
106 /// Possible values of mtime_:
107 /// -1: file hasn't been examined
108 /// 0: we looked, and file doesn't exist
109 /// >0: actual file's mtime
112 /// Dirty is true when the underlying file is out-of-date.
113 /// But note that Edge::outputs_ready_ is also used in judging which
117 /// The Edge that produces this Node, or NULL when there is no
118 /// known edge to produce it.
121 /// All Edges that use this Node as an input.
122 vector<Edge*> out_edges_;
124 /// A dense integer id for the node, assigned and used by DepsLog.
128 /// An edge in the dependency graph; links between Nodes using Rules.
130 Edge() : rule_(NULL), pool_(NULL), env_(NULL),
131 outputs_ready_(false), deps_missing_(false),
132 implicit_deps_(0), order_only_deps_(0), implicit_outs_(0) {}
134 /// Return true if all inputs' in-edges are ready.
135 bool AllInputsReady() const;
137 /// Expand all variables in a command and return it as a string.
138 /// If incl_rsp_file is enabled, the string will also contain the
139 /// full contents of a response file (if applicable)
140 string EvaluateCommand(bool incl_rsp_file = false);
142 /// Returns the shell-escaped value of |key|.
143 string GetBinding(const string& key);
144 bool GetBindingBool(const string& key);
146 /// Like GetBinding("depfile"), but without shell escaping.
147 string GetUnescapedDepfile();
148 /// Like GetBinding("rspfile"), but without shell escaping.
149 string GetUnescapedRspfile();
151 void Dump(const char* prefix="") const;
155 vector<Node*> inputs_;
156 vector<Node*> outputs_;
161 const Rule& rule() const { return *rule_; }
162 Pool* pool() const { return pool_; }
163 int weight() const { return 1; }
164 bool outputs_ready() const { return outputs_ready_; }
166 // There are three types of inputs.
167 // 1) explicit deps, which show up as $in on the command line;
168 // 2) implicit deps, which the target depends on implicitly (e.g. C headers),
169 // and changes in them cause the target to rebuild;
170 // 3) order-only deps, which are needed before the target builds but which
171 // don't cause the target to rebuild.
172 // These are stored in inputs_ in that order, and we keep counts of
173 // #2 and #3 when we need to access the various subsets.
175 int order_only_deps_;
176 bool is_implicit(size_t index) {
177 return index >= inputs_.size() - order_only_deps_ - implicit_deps_ &&
178 !is_order_only(index);
180 bool is_order_only(size_t index) {
181 return index >= inputs_.size() - order_only_deps_;
184 // There are two types of outputs.
185 // 1) explicit outs, which show up as $out on the command line;
186 // 2) implicit outs, which the target generates but are not part of $out.
187 // These are stored in outputs_ in that order, and we keep a count of
188 // #2 to use when we need to access the various subsets.
190 bool is_implicit_out(size_t index) const {
191 return index >= outputs_.size() - implicit_outs_;
194 bool is_phony() const;
195 bool use_console() const;
199 /// ImplicitDepLoader loads implicit dependencies, as referenced via the
200 /// "depfile" attribute in build files.
201 struct ImplicitDepLoader {
202 ImplicitDepLoader(State* state, DepsLog* deps_log,
203 DiskInterface* disk_interface)
204 : state_(state), disk_interface_(disk_interface), deps_log_(deps_log) {}
206 /// Load implicit dependencies for \a edge.
207 /// @return false on error (without filling \a err if info is just missing
209 bool LoadDeps(Edge* edge, string* err);
211 DepsLog* deps_log() const {
216 /// Load implicit dependencies for \a edge from a depfile attribute.
217 /// @return false on error (without filling \a err if info is just missing).
218 bool LoadDepFile(Edge* edge, const string& path, string* err);
220 /// Load implicit dependencies for \a edge from the DepsLog.
221 /// @return false on error (without filling \a err if info is just missing).
222 bool LoadDepsFromLog(Edge* edge, string* err);
224 /// Preallocate \a count spaces in the input array on \a edge, returning
225 /// an iterator pointing at the first new space.
226 vector<Node*>::iterator PreallocateSpace(Edge* edge, int count);
228 /// If we don't have a edge that generates this input already,
229 /// create one; this makes us not abort if the input is missing,
230 /// but instead will rebuild in that circumstance.
231 void CreatePhonyInEdge(Node* node);
234 DiskInterface* disk_interface_;
239 /// DependencyScan manages the process of scanning the files in a graph
240 /// and updating the dirty/outputs_ready state of all the nodes and edges.
241 struct DependencyScan {
242 DependencyScan(State* state, BuildLog* build_log, DepsLog* deps_log,
243 DiskInterface* disk_interface)
244 : build_log_(build_log),
245 disk_interface_(disk_interface),
246 dep_loader_(state, deps_log, disk_interface) {}
248 /// Examine inputs, outputs, and command lines to judge whether an edge
249 /// needs to be re-run, and update outputs_ready_ and each outputs' |dirty_|
250 /// state accordingly.
251 /// Returns false on failure.
252 bool RecomputeDirty(Edge* edge, string* err);
254 /// Recompute whether any output of the edge is dirty, if so sets |*dirty|.
255 /// Returns false on failure.
256 bool RecomputeOutputsDirty(Edge* edge, Node* most_recent_input,
257 bool* dirty, string* err);
259 BuildLog* build_log() const {
262 void set_build_log(BuildLog* log) {
266 DepsLog* deps_log() const {
267 return dep_loader_.deps_log();
271 /// Recompute whether a given single output should be marked dirty.
272 /// Returns true if so.
273 bool RecomputeOutputDirty(Edge* edge, Node* most_recent_input,
274 const string& command, Node* output);
276 BuildLog* build_log_;
277 DiskInterface* disk_interface_;
278 ImplicitDepLoader dep_loader_;
281 #endif // NINJA_GRAPH_H_