aboutsummaryrefslogtreecommitdiff
path: root/build/b.cxx
blob: 4779a572ab914fb3f6a93e2223c3f6580f3115af (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
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
// file      : build/b.cxx -*- C++ -*-
// copyright : Copyright (c) 2014-2015 Code Synthesis Tools CC
// license   : MIT; see accompanying LICENSE file

#include <time.h>      // tzset()
#include <string.h>    // strerror()

#include <stdlib.h>    // getenv()
#include <unistd.h>    // getuid()
#include <sys/types.h> // uid_t
#include <pwd.h>       // struct passwd, getpwuid()

#include <vector>
#include <cassert>
#include <fstream>
#include <sstream>
#include <iterator> // make_move_iterator()
#include <iostream> //@@ TMP, for dump()
#include <typeinfo>
#include <system_error>

#include <build/spec>
#include <build/name>
#include <build/scope>
#include <build/target>
#include <build/prerequisite>
#include <build/rule>
#include <build/algorithm>
#include <build/process>
#include <build/diagnostics>
#include <build/context>
#include <build/utility>
#include <build/dump>

#include <build/lexer>
#include <build/parser>

using namespace std;

namespace build
{
  void
  dump ()
  {
    cout << endl;

    for (const auto& pt: targets)
    {
      target& t (*pt);

      cout << t << ':';

      for (const auto& p: t.prerequisites)
      {
        cout << ' ' << p;
      }

      cout << endl;
    }

    cout << endl;
  }
}

#include <build/native>

#include <build/cxx/target>
#include <build/cxx/rule>


using namespace build;

int
main (int argc, char* argv[])
{
  try
  {
    tracer trace ("main");

    // Initialize time conversion data that is used by localtime_r().
    //
    tzset ();

    // Trace verbosity.
    //
    verb = 5;

    // Register target types.
    //
    target_types.insert (file::static_type);
    target_types.insert (dir::static_type);
    target_types.insert (fsdir::static_type);

    target_types.insert (exe::static_type);
    target_types.insert (obj::static_type);

    target_types.insert (cxx::h::static_type);
    target_types.insert (cxx::c::static_type);

    target_types.insert (cxx::cxx::static_type);
    target_types.insert (cxx::hxx::static_type);
    target_types.insert (cxx::ixx::static_type);
    target_types.insert (cxx::txx::static_type);

    // Enter built-in meta-operation and operation names. Loading of
    // the buildfiles can result in additional names being added (via
    // module loading).
    //
    meta_operations.emplace ("perform"); // Default.
    meta_operations.emplace ("configure");
    meta_operations.emplace ("disfigure");

    operations.emplace ("update"); // Default.
    operations.emplace ("clean");

    // Figure out work and home directories.
    //
    work = path::current ();

    if (const char* h = getenv ("HOME"))
      home = path (h);
    else
    {
      struct passwd* pw (getpwuid (getuid ()));

      if (pw == nullptr)
      {
        const char* msg (strerror (errno));
        fail << "unable to determine home directory: " << msg;
      }

      home = path (pw->pw_dir);
    }

    if (verb >= 4)
    {
      trace << "work dir: " << work.string ();
      trace << "home dir: " << home.string ();
    }

    // Create root scope. For Win32 we use the empty path since there
    // is no such "real" root path. On POSIX, however, this is a real
    // path. See the comment in <build/path-map> for details.
    //
#ifdef _WIN32
    root_scope = &scopes[path ()];
#else
    root_scope = &scopes[path ("/")];
#endif

    root_scope->variables["work"] = work;
    root_scope->variables["home"] = home;

    // Parse the buildspec.
    //
    buildspec bspec;
    {
      // Merge all the individual buildspec arguments into a single
      // string. Instead, we could also parse them individually (
      // and merge the result). The benefit of doing it this way
      // is potentially better diagnostics (i.e., we could have
      // used <buildspec-1>, <buildspec-2> to give the idea about
      // which argument is invalid).
      //
      string s;
      for (int i (1); i != argc;)
      {
        s += argv[i];
        if (++i != argc)
          s += ' ';
      }

      istringstream is (s);
      is.exceptions (ifstream::failbit | ifstream::badbit);
      parser p;

      try
      {
        bspec = p.parse_buildspec (is, "<buildspec>");
      }
      catch (const std::ios_base::failure&)
      {
        fail << "failed to parse buildspec string";
      }
    }

    level4 ([&]{trace << "buildspec: " << bspec;});

    // Load all the buildfiles.
    //
    if (bspec.empty ())
      bspec.push_back (metaopspec ()); // Default meta-operation.

    for (metaopspec& ms: bspec)
    {
      if (ms.empty ())
        ms.push_back (opspec ()); // Default operation.

      for (opspec& os: ms)
      {
        if (os.empty ())
          // Default target: dir{}.
          //
          os.push_back (targetspec (name ("dir", path (), string ())));

        for (targetspec& ts: os)
        {
          name& tn (ts.name);

          // First figure out the out_base of this target. The logic
          // is as follows: if a directory was specified in any form,
          // then that's the out_base. Otherwise, we check if the name
          // value has a directory prefix. This has a good balance of
          // control and the expected result in most cases.
          //
          path out_base (tn.dir);
          if (out_base.empty ())
          {
            // See if there is a directory part in value. We cannot
            // assume it is a valid filesystem name so we will have
            // to do the splitting manually.
            //
            path::size_type i (path::traits::rfind_separator (tn.value));

            if (i != string::npos)
              out_base = path (tn.value, i != 0 ? i : 1); // Special case: "/".
          }

          if (out_base.relative ())
            out_base = work / out_base;

          out_base.normalize ();

          path& src_base (ts.src_base);
          if (src_base.empty ())
          {
            //@@ TODO: Configured case: find out_root (looking for
            //   "build/bootstrap.build" or some such), then src_root
            //   (stored in this file). Need to also detect the in-tree
            //   build.
            //

            // If that doesn't work out (e.g., the first build), then
            // default to the working directory as src_base.
            //
            src_base = work;
          }

          if (src_base.relative ())
            src_base = work / src_base;

          src_base.normalize ();

          path src_root;
          path out_root;

          // The project's root directory is the one that contains the build/
          // sub-directory which contains the pre.build file.
          //
          for (path d (src_base), f ("build/pre.build");
               !d.root () && d != home;
               d = d.directory ())
          {
            if (path_mtime (d / f) != timestamp_nonexistent)
            {
              src_root = d;
              break;
            }
          }

          // If there is no such sub-directory, assume this is a simple
          // project with src_root being the same as src_base.
          //
          if (src_root.empty ())
          {
            src_root = src_base;
            out_root = out_base;
          }
          else
            out_root = out_base.directory (src_base.leaf (src_root));

          if (verb >= 4)
          {
            trace << tn << ':';
            trace << "  out_base: " << out_base.string ();
            trace << "  src_base: " << src_base.string ();
            trace << "  out_root: " << out_root.string ();
            trace << "  src_root: " << src_root.string ();
          }

          // Create project root and base scopes, set the corresponding
          // variables. Note that we might already have all of this set
          // up as a result of one of the preceding target processing.
          //
          scope& proot_scope (scopes[out_root]);
          scope& pbase_scope (scopes[out_base]);

          proot_scope.variables["out_root"] = move (out_root);
          proot_scope.variables["src_root"] = move (src_root);

          pbase_scope.variables["out_base"] = out_base;
          pbase_scope.variables["src_base"] = src_base;

          // Parse the buildfile.
          //
          path bf (src_base / path ("buildfile"));

          // Check if this buildfile has already been loaded.
          //
          if (!proot_scope.buildfiles.insert (bf).second)
          {
            level4 ([&]{trace << "skipping already loaded " << bf;});
            continue;
          }

          level4 ([&]{trace << "loading " << bf;});

          ifstream ifs (bf.string ());
          if (!ifs.is_open ())
            fail << "unable to open " << bf;

          ifs.exceptions (ifstream::failbit | ifstream::badbit);
          parser p;

          try
          {
            p.parse_buildfile (ifs, bf, pbase_scope, proot_scope);
          }
          catch (const std::ios_base::failure&)
          {
            fail << "failed to read from " << bf;
          }
        }
      }
    }

    dump_scopes ();
    dump ();

    // At this stage we know all the names of meta-operations and
    // operations so "lift" names that we assumed (from buildspec
    // syntax) were operations but are actually meta-operations.
    // Also convert empty names (which means they weren't explicitly
    // specified) to the defaults and verify that all the names are
    // known.
    //
    for (auto mi (bspec.begin ()); mi != bspec.end (); ++mi)
    {
      metaopspec& ms (*mi);
      const location l ("<buildspec>", 1, 0); //@@ TODO

      for (auto oi (ms.begin ()); oi != ms.end (); ++oi)
      {
        opspec& os (*oi);
        const location l ("<buildspec>", 1, 0); //@@ TODO

        if (os.name.empty ())
        {
          os.name = "update";
          continue;
        }

        if (meta_operations.count (os.name))
        {
          if (!ms.name.empty ())
            fail (l) << "nested meta-operation " << os.name;

          // The easy case is when the metaopspec contains a
          // single opspec (us). In this case we can just move
          // the name.
          //
          if (ms.size () == 1)
          {
            ms.name = move (os.name);
            os.name = "update";
            continue;
          }
          // The hard case is when there are other operations that
          // need to keep their original meta-operation. In this
          // case we have to "split" the metaopspec, in the worst
          // case scenario, into three parts: prefix, us, and suffix.
          //
          else
          {
            if (oi != ms.begin ()) // We have a prefix of opspec's.
            {
              // Keep the prefix in the original metaopspec and move
              // the suffix into a new one that is inserted after the
              // prefix. Then simply let the loop finish with the prefix
              // and naturally move to the suffix (in other words, we
              // are reducing this case to the one without a prefix).
              //
              metaopspec suffix;
              suffix.insert (suffix.end (),
                             make_move_iterator (oi),
                             make_move_iterator (ms.end ()));
              ms.resize (oi - ms.begin ());

              mi = bspec.insert (++mi, move (suffix)); // Insert after prefix.
              --mi; // Move back to prefix.
              break;
            }

            // We are the first element and have a suffix of opspec's
            // (otherwise one of the previous cases would have matched).
            //
            assert (oi == ms.begin () && (oi + 1) != ms.end ());

            // Move this opspec into a new metaopspec and insert it before
            // the current one. Then continue with the next opspec.
            //
            metaopspec prefix (move (os.name));
            os.name = "update";
            prefix.push_back (move (os));
            ms.erase (oi);

            mi = bspec.insert (mi, move (prefix)); // Insert before suffix.
            break; // Restart inner loop: outer loop ++ moves back to suffix.
          }
        }

        if (!operations.count (os.name))
          fail (l) << "unknown operation " << os.name;
      }

      // Note: using mi rather than ms since ms is invalidated by above
      // insert()'s.
      //
      if (mi->name.empty ())
        mi->name = "perform";
      else if (!meta_operations.count (mi->name))
        fail (l) << "unknown meta-operation " << mi->name;
    }

    level4 ([&]{trace << "buildspec: " << bspec;});

    // Register rules.
    //
    cxx::link cxx_link;
    rules[typeid (exe)].emplace ("cxx.gnu.link", cxx_link);

    cxx::compile cxx_compile;
    rules[typeid (obj)].emplace ("cxx.gnu.compile", cxx_compile);

    dir_rule dir_r;
    rules[typeid (dir)].emplace ("dir", dir_r);

    fsdir_rule fsdir_r;
    rules[typeid (fsdir)].emplace ("fsdir", fsdir_r);

    path_rule path_r;
    rules[typeid (path_target)].emplace ("path", path_r);


    // Do the operations. We do meta-operations and operations sequentially
    // (no parallelism).
    //
    for (metaopspec& ms: bspec)
    {
      for (opspec& os: ms)
      {
        // But multiple targets in the same operation can be done in
        // parallel.
        //
        vector<reference_wrapper<target>> tgs;
        tgs.reserve (os.size ());

        // First resolve and match all the targets. We don't want to
        // start building before we know how for all the targets in
        // this operation.
        //
        for (targetspec& ts: os)
        {
          name& tn (ts.name);
          const location l ("<buildspec>", 1, 0); //@@ TODO

          const string* e;
          const target_type* ti (target_types.find (tn, e));

          if (ti == nullptr)
            fail (l) << "unknown target type " << tn.type;

          // If the directory is relative, assume it is relative to work
          // (must be consistent with how we derive out_base).
          //
          path& d (tn.dir);

          if (d.relative ())
            d = work / d;

          d.normalize ();

          target_set::key tk {ti, &d, &tn.value, &e};
          auto i (targets.find (tk, trace));
          if (i == targets.end ())
            fail (l) << "unknown target " << tk;

          target& t (**i);

          if (!t.recipe ())
          {
            level4 ([&]{trace << "matching target " << t;});
            match (t);
          }

          tgs.push_back (t);
        }

        dump ();

        // Now build.
        //
        for (target& t: tgs)
        {
          // The target might have already been updated indirectly. We
          // still want to inform the user about its status since they
          // requested its update explicitly.
          //
          target_state s (t.state ());
          if (s == target_state::unknown)
          {
            level4 ([&]{trace << "updating target " << t;});
            s = update (t);
          }

          switch (s)
          {
          case target_state::uptodate:
            {
              info << "target " << t << " is up to date";
              break;
            }
          case target_state::updated:
            break;
          case target_state::failed:
            //@@ This could probably happen in a parallel build.
          case target_state::unknown:
            assert (false);
          }
        }
      }
    }
  }
  catch (const failed&)
  {
    return 1; // Diagnostics has already been issued.
  }
  catch (const std::exception& e)
  {
    error << e.what ();
    return 1;
  }
}