Ninja
eval_env.cc
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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 #include <assert.h>
16 
17 #include "eval_env.h"
18 
19 using namespace std;
20 
21 string BindingEnv::LookupVariable(const string& var) {
22  map<string, string>::iterator i = bindings_.find(var);
23  if (i != bindings_.end())
24  return i->second;
25  if (parent_)
26  return parent_->LookupVariable(var);
27  return "";
28 }
29 
30 void BindingEnv::AddBinding(const string& key, const string& val) {
31  bindings_[key] = val;
32 }
33 
34 void BindingEnv::AddRule(std::unique_ptr<const Rule> rule) {
35  assert(LookupRuleCurrentScope(rule->name()) == NULL);
36  rules_[rule->name()] = std::move(rule);
37 }
38 
39 const Rule* BindingEnv::LookupRuleCurrentScope(const string& rule_name) {
40  auto i = rules_.find(rule_name);
41  if (i == rules_.end())
42  return NULL;
43  return i->second.get();
44 }
45 
46 const Rule* BindingEnv::LookupRule(const string& rule_name) {
47  auto i = rules_.find(rule_name);
48  if (i != rules_.end())
49  return i->second.get();
50  if (parent_)
51  return parent_->LookupRule(rule_name);
52  return NULL;
53 }
54 
55 void Rule::AddBinding(const string& key, const EvalString& val) {
56  bindings_[key] = val;
57 }
58 
59 const EvalString* Rule::GetBinding(const string& key) const {
60  Bindings::const_iterator i = bindings_.find(key);
61  if (i == bindings_.end())
62  return NULL;
63  return &i->second;
64 }
65 
66 std::unique_ptr<Rule> Rule::Phony() {
67  auto rule = std::unique_ptr<Rule>(new Rule("phony"));
68  rule->phony_ = true;
69  return rule;
70 }
71 
72 bool Rule::IsPhony() const {
73  return phony_;
74 }
75 
76 // static
77 bool Rule::IsReservedBinding(const string& var) {
78  return var == "command" ||
79  var == "depfile" ||
80  var == "dyndep" ||
81  var == "description" ||
82  var == "deps" ||
83  var == "generator" ||
84  var == "pool" ||
85  var == "restat" ||
86  var == "rspfile" ||
87  var == "rspfile_content" ||
88  var == "msvc_deps_prefix";
89 }
90 
91 const map<string, std::unique_ptr<const Rule>>& BindingEnv::GetRules() const {
92  return rules_;
93 }
94 
95 string BindingEnv::LookupWithFallback(const string& var,
96  const EvalString* eval,
97  Env* env) {
98  map<string, string>::iterator i = bindings_.find(var);
99  if (i != bindings_.end())
100  return i->second;
101 
102  if (eval)
103  return eval->Evaluate(env);
104 
105  if (parent_)
106  return parent_->LookupVariable(var);
107 
108  return "";
109 }
110 
111 string EvalString::Evaluate(Env* env) const {
112  if (parsed_.empty()) {
113  return single_token_;
114  }
115 
116  string result;
117  for (TokenList::const_iterator i = parsed_.begin(); i != parsed_.end(); ++i) {
118  if (i->second == RAW)
119  result.append(i->first);
120  else
121  result.append(env->LookupVariable(i->first));
122  }
123  return result;
124 }
125 
127  if (parsed_.empty()) {
128  single_token_.append(text.begin(), text.end());
129  } else if (!parsed_.empty() && parsed_.back().second == RAW) {
130  parsed_.back().first.append(text.begin(), text.end());
131  } else {
132  parsed_.push_back(std::make_pair(text.AsString(), RAW));
133  }
134 }
135 
137  if (parsed_.empty() && !single_token_.empty()) {
138  // Going from one to two tokens, so we can no longer apply
139  // our single_token_ optimization and need to push everything
140  // onto the vector.
141  parsed_.push_back(std::make_pair(std::move(single_token_), RAW));
142  }
143  parsed_.push_back(std::make_pair(text.AsString(), SPECIAL));
144 }
145 
146 string EvalString::Serialize() const {
147  string result;
148  if (parsed_.empty() && !single_token_.empty()) {
149  result.append("[");
150  result.append(single_token_);
151  result.append("]");
152  } else {
153  for (const auto& pair : parsed_) {
154  result.append("[");
155  if (pair.second == SPECIAL)
156  result.append("$");
157  result.append(pair.first.begin(), pair.first.end());
158  result.append("]");
159  }
160  }
161  return result;
162 }
163 
164 string EvalString::Unparse() const {
165  string result;
166  if (parsed_.empty() && !single_token_.empty()) {
167  result.append(single_token_.begin(), single_token_.end());
168  } else {
169  for (TokenList::const_iterator i = parsed_.begin();
170  i != parsed_.end(); ++i) {
171  bool special = (i->second == SPECIAL);
172  if (special)
173  result.append("${");
174  result.append(i->first.begin(), i->first.end());
175  if (special)
176  result.append("}");
177  }
178  }
179  return result;
180 }
Definition: hash_map.h:26
std::string LookupWithFallback(const std::string &var, const EvalString *eval, Env *env)
This is tricky.
Definition: eval_env.cc:95
void AddBinding(const std::string &key, const std::string &val)
Definition: eval_env.cc:30
const Rule * LookupRule(const std::string &rule_name)
Definition: eval_env.cc:46
const std::map< std::string, std::unique_ptr< const Rule > > & GetRules() const
Definition: eval_env.cc:91
const Rule * LookupRuleCurrentScope(const std::string &rule_name)
Definition: eval_env.cc:39
virtual std::string LookupVariable(const std::string &var)
Definition: eval_env.cc:21
void AddRule(std::unique_ptr< const Rule > rule)
Definition: eval_env.cc:34
An interface for a scope for variable (e.g. "$foo") lookups.
Definition: eval_env.h:28
virtual std::string LookupVariable(const std::string &var)=0
A tokenized string that contains variable references.
Definition: eval_env.h:35
std::string Evaluate(Env *env) const
Definition: eval_env.cc:111
std::string Unparse() const
Definition: eval_env.cc:164
void AddSpecial(StringPiece text)
Definition: eval_env.cc:136
std::string Serialize() const
Construct a human-readable representation of the parsed state, for use in tests.
Definition: eval_env.cc:146
void AddText(StringPiece text)
Definition: eval_env.cc:126
An invocable build command and associated metadata (description, etc.).
Definition: eval_env.h:66
const EvalString * GetBinding(const std::string &key) const
Definition: eval_env.cc:59
void AddBinding(const std::string &key, const EvalString &val)
Definition: eval_env.cc:55
static std::unique_ptr< Rule > Phony()
Definition: eval_env.cc:66
bool IsPhony() const
Definition: eval_env.cc:72
static bool IsReservedBinding(const std::string &var)
Definition: eval_env.cc:77
StringPiece represents a slice of a string whose memory is managed externally.
Definition: string_piece.h:25
const_iterator end() const
Definition: string_piece.h:54
std::string AsString() const
Convert the slice into a full-fledged std::string, copying the data into a new string.
Definition: string_piece.h:46
const_iterator begin() const
Definition: string_piece.h:50