summaryrefslogtreecommitdiffstats
path: root/src/parsers.cc
blob: c3844fbb112dd6acac505a83f00f5553e9d0f4ca (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
// Copyright 2011 Google Inc. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "parsers.h"

#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>

#include "graph.h"
#include "metrics.h"
#include "state.h"
#include "util.h"

ManifestParser::ManifestParser(State* state, FileReader* file_reader)
  : state_(state), file_reader_(file_reader) {
  env_ = &state->bindings_;
}
bool ManifestParser::Load(const string& filename, string* err) {
  string contents;
  string read_err;
  if (!file_reader_->ReadFile(filename, &contents, &read_err)) {
    *err = "loading '" + filename + "': " + read_err;
    return false;
  }
  contents.resize(contents.size() + 10);
  return Parse(filename, contents, err);
}

bool ManifestParser::Parse(const string& filename, const string& input,
                           string* err) {
  METRIC_RECORD(".ninja parse");
  lexer_.Start(filename, input);

  for (;;) {
    Lexer::Token token = lexer_.ReadToken();
    switch (token) {
    case Lexer::BUILD:
      if (!ParseEdge(err))
        return false;
      break;
    case Lexer::RULE:
      if (!ParseRule(err))
        return false;
      break;
    case Lexer::DEFAULT:
      if (!ParseDefault(err))
        return false;
      break;
    case Lexer::IDENT: {
      lexer_.UnreadToken();
      string name;
      EvalString value;
      if (!ParseLet(&name, &value, err))
        return false;
      env_->AddBinding(name, value.Evaluate(env_));
      break;
    }
    case Lexer::INCLUDE:
      if (!ParseFileInclude(false, err))
        return false;
      break;
    case Lexer::SUBNINJA:
      if (!ParseFileInclude(true, err))
        return false;
      break;
    case Lexer::ERROR:
      return lexer_.Error("lexing error", err);
    case Lexer::TEOF:
      return true;
    case Lexer::NEWLINE:
      break;
    default:
      return lexer_.Error(string("unexpected ") + Lexer::TokenName(token),
                          err);
    }
  }
  return false;  // not reached
}

bool ManifestParser::ParseRule(string* err) {
  string name;
  if (!lexer_.ReadIdent(&name))
    return lexer_.Error("expected rule name", err);

  if (!ExpectToken(Lexer::NEWLINE, err))
    return false;

  if (state_->LookupRule(name) != NULL) {
    *err = "duplicate rule '" + name + "'";
    return false;
  }

  Rule* rule = new Rule(name);  // XXX scoped_ptr

  while (lexer_.PeekToken(Lexer::INDENT)) {
    string key;
    EvalString value;
    if (!ParseLet(&key, &value, err))
      return false;

    if (key == "command") {
      rule->command_ = value;
    } else if (key == "depfile") {
      rule->depfile_ = value;
    } else if (key == "description") {
      rule->description_ = value;
    } else if (key == "generator") {
      rule->generator_ = true;
    } else if (key == "restat") {
      rule->restat_ = true;
    } else if (key == "rspfile") {
      rule->rspfile_ = value;
    } else if (key == "rspfile_content") {
      rule->rspfile_content_ = value;
    } else {
      // Die on other keyvals for now; revisit if we want to add a
      // scope here.
      return lexer_.Error("unexpected variable '" + key + "'", err);
    }
  }

  if (rule->rspfile_.empty() != rule->rspfile_content_.empty())
    return lexer_.Error("rspfile and rspfile_content need to be both specified", err);

  if (rule->command_.empty())
    return lexer_.Error("expected 'command =' line", err);

  state_->AddRule(rule);
  return true;
}

bool ManifestParser::ParseLet(string* key, EvalString* value, string* err) {
  if (!lexer_.ReadIdent(key))
    return false;
  if (!ExpectToken(Lexer::EQUALS, err))
    return false;
  if (!lexer_.ReadVarValue(value, err))
    return false;
  return true;
}

bool ManifestParser::ParseDefault(string* err) {
  EvalString eval;
  if (!lexer_.ReadPath(&eval, err))
    return false;
  if (eval.empty())
    return lexer_.Error("expected target name", err);

  do {
    string path = eval.Evaluate(env_);
    string path_err;
    if (!CanonicalizePath(&path, &path_err))
      return lexer_.Error(path_err, err);
    if (!state_->AddDefault(path, &path_err))
      return lexer_.Error(path_err, err);

    eval.Clear();
    if (!lexer_.ReadPath(&eval, err))
      return false;
  } while (!eval.empty());

  if (!ExpectToken(Lexer::NEWLINE, err))
    return false;

  return true;
}

bool ManifestParser::ParseEdge(string* err) {
  vector<EvalString> ins, outs;

  {
    EvalString out;
    if (!lexer_.ReadPath(&out, err))
      return false;
    if (out.empty())
      return lexer_.Error("expected path", err);

    do {
      outs.push_back(out);

      out.Clear();
      if (!lexer_.ReadPath(&out, err))
        return false;
    } while (!out.empty());
  }

  if (!ExpectToken(Lexer::COLON, err))
    return false;

  string rule_name;
  if (!lexer_.ReadIdent(&rule_name))
    return lexer_.Error("expected build command name", err);

  const Rule* rule = state_->LookupRule(rule_name);
  if (!rule)
    return lexer_.Error("unknown build rule '" + rule_name + "'", err);

  for (;;) {
    // XXX should we require one path here?
    EvalString in;
    if (!lexer_.ReadPath(&in, err))
      return false;
    if (in.empty())
      break;
    ins.push_back(in);
  }

  // Add all order-only deps, counting how many as we go.
  int implicit = 0;
  if (lexer_.PeekToken(Lexer::PIPE)) {
    for (;;) {
      EvalString in;
      if (!lexer_.ReadPath(&in, err))
        return err;
      if (in.empty())
        break;
      ins.push_back(in);
      ++implicit;
    }
  }

  // Add all order-only deps, counting how many as we go.
  int order_only = 0;
  if (lexer_.PeekToken(Lexer::PIPE2)) {
    for (;;) {
      EvalString in;
      if (!lexer_.ReadPath(&in, err))
        return false;
      if (in.empty())
        break;
      ins.push_back(in);
      ++order_only;
    }
  }

  if (!ExpectToken(Lexer::NEWLINE, err))
    return false;

  // Default to using outer env.
  BindingEnv* env = env_;

  // But create and fill a nested env if there are variables in scope.
  if (lexer_.PeekToken(Lexer::INDENT)) {
    // XXX scoped_ptr to handle error case.
    env = new BindingEnv(env_);
    do {
      string key;
      EvalString val;
      if (!ParseLet(&key, &val, err))
        return false;
      env->AddBinding(key, val.Evaluate(env_));
    } while (lexer_.PeekToken(Lexer::INDENT));
  }

  Edge* edge = state_->AddEdge(rule);
  edge->env_ = env;
  for (vector<EvalString>::iterator i = ins.begin(); i != ins.end(); ++i) {
    string path = i->Evaluate(env);
    string path_err;
    if (!CanonicalizePath(&path, &path_err))
      return lexer_.Error(path_err, err);
    state_->AddIn(edge, path);
  }
  for (vector<EvalString>::iterator i = outs.begin(); i != outs.end(); ++i) {
    string path = i->Evaluate(env);
    string path_err;
    if (!CanonicalizePath(&path, &path_err))
      return lexer_.Error(path_err, err);
    state_->AddOut(edge, path);
  }
  edge->implicit_deps_ = implicit;
  edge->order_only_deps_ = order_only;

  return true;
}

bool ManifestParser::ParseFileInclude(bool new_scope, string* err) {
  // XXX this should use ReadPath!
  EvalString eval;
  if (!lexer_.ReadPath(&eval, err))
    return false;
  string path = eval.Evaluate(env_);

  string contents;
  string read_err;
  if (!file_reader_->ReadFile(path, &contents, &read_err))
    return lexer_.Error("loading '" + path + "': " + read_err, err);

  ManifestParser subparser(state_, file_reader_);
  if (new_scope) {
    subparser.env_ = new BindingEnv(env_);
  } else {
    subparser.env_ = env_;
  }

  if (!subparser.Parse(path, contents, err))
    return false;

  if (!ExpectToken(Lexer::NEWLINE, err))
    return false;

  return true;
}

bool ManifestParser::ExpectToken(Lexer::Token expected, string* err) {
  Lexer::Token token = lexer_.ReadToken();
  if (token != expected) {
    string message = string("expected ") + Lexer::TokenName(expected);
    message += string(", got ") + Lexer::TokenName(token);
    message += Lexer::TokenErrorHint(expected);
    return lexer_.Error(message, err);
  }
  return true;
}