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
554
555
556
557
558
559
560
|
// file : libbuild2/module.cxx -*- C++ -*-
// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
// license : MIT; see accompanying LICENSE file
#include <libbuild2/module.hxx>
#ifndef BUILD2_BOOTSTRAP
# ifndef _WIN32
# include <dlfcn.h>
# else
# include <libbutl/win32-utility.hxx>
# endif
#endif
#include <libbuild2/file.hxx> // import_*()
#include <libbuild2/scope.hxx>
#include <libbuild2/target.hxx>
#include <libbuild2/variable.hxx>
#include <libbuild2/operation.hxx>
#include <libbuild2/diagnostics.hxx>
// Core modules bundled with libbuild2.
//
#include <libbuild2/dist/init.hxx>
#include <libbuild2/test/init.hxx>
#include <libbuild2/config/init.hxx>
#include <libbuild2/install/init.hxx>
using namespace std;
using namespace butl;
namespace build2
{
loaded_module_map loaded_modules;
// Sorted array of bundled modules (excluding core modules bundled with
// libbuild2; see below).
//
static const char* bundled_modules[] = {
"bash",
"bin",
"c",
"cc",
"cxx",
"in",
"version"
};
static inline bool
bundled_module (const string& mod)
{
return binary_search (
bundled_modules,
bundled_modules + sizeof (bundled_modules) / sizeof (*bundled_modules),
mod);
}
static module_load_function*
import_module (scope& bs,
const string& mod,
const location& loc,
bool boot,
bool opt)
{
tracer trace ("import_module");
// Take care of core modules that are bundled with libbuild2 in case they
// are not pre-loaded by the driver.
//
if (mod == "config") return &config::build2_config_load;
else if (mod == "dist") return &dist::build2_dist_load;
else if (mod == "install") return &install::build2_install_load;
else if (mod == "test") return &test::build2_test_load;
bool bundled (bundled_module (mod));
// Importing external modules during bootstrap is problematic: we haven't
// loaded config.build nor entered all the variable overrides so it's not
// clear what import() can do except confuse matters. So this requires
// more thinking.
//
if (boot && !bundled)
{
fail (loc) << "unable to load build system module " << mod <<
info << "loading external modules during bootstrap is not yet "
<< "supported";
}
module_load_function* r (nullptr);
// No dynamic loading of build system modules during bootstrap.
//
#ifdef BUILD2_BOOTSTRAP
if (!opt)
fail (loc) << "unknown build system module " << mod <<
info << "running bootstrap build system";
#else
context& ctx (bs.ctx);
// See if we can import a target for this module.
//
path lib;
// If this is a top-level module update, then we use the nested context.
// If, however, this is a nested module update (i.e., a module required
// while updating a module), then we reuse the same module context.
//
// If you are wondering why don't we always use the top-level context, the
// reason is that it might be running a different meta/operation (say,
// configure or clean); with the nested context we always know it is
// perform update.
//
// And the reason for not simply creating a nested context for each nested
// module update is due to the no-overlap requirement of contexts: while
// we can naturally expect the top-level project(s) and the modules they
// require to be in separate configurations that don't shared anything,
// the same does not hold for build system modules. In fact, it would be
// natural to have a single build configuration for all of them and they
// could plausibly share some common libraries.
//
bool nested (ctx.module_context == &ctx);
// If this is one of the bundled modules, the project name is build2,
// otherwise -- libbuild2-<mod>.
//
project_name proj (bundled ? "build2" : "libbuild2-" + mod);
// The target we are looking for is <prj>%libs{build2-<mod>}.
//
// We only search in subprojects if this is a nested module update
// (remember, if it's top-level, then it must be in an isolated
// configuration).
//
pair<name, dir_path> ir (
import_search (bs,
name (proj, dir_path (), "libs", "build2-" + mod),
loc,
nested /* subprojects */));
if (!ir.second.empty ())
{
// We found the module as a target in a project. Now we need to update
// the target (which will also give us the shared library path).
//
l5 ([&]{trace << "found " << ir.first << " in " << ir.second;});
// Create the build context if necessary.
//
if (ctx.module_context == nullptr)
{
if (!ctx.module_context_storage)
fail (loc) << "unable to update build system module " << mod <<
info << "updating of build system modules is disabled";
assert (*ctx.module_context_storage == nullptr);
// Since we are using the same scheduler, it makes sense to reuse the
// same mutex shards. Also disable nested module context for good
// measure.
//
ctx.module_context_storage->reset (
new context (ctx.sched,
ctx.mutex_shards,
false, /* dry_run */
ctx.keep_going,
ctx.global_var_overrides, /* cmd_vars */
nullopt)); /* module_context */
// We use the same context for building any nested modules that
// might be required while building modules.
//
ctx.module_context = ctx.module_context_storage->get ();
ctx.module_context->module_context = ctx.module_context;
// Setup the context to perform update. In a sense we have a long-
// running perform meta-operation batch (indefinite, in fact, since we
// never call the meta-operation's *_post() callbacks) in which we
// periodically execute the update operation.
//
if (mo_perform.meta_operation_pre != nullptr)
mo_perform.meta_operation_pre ({} /* parameters */, loc);
ctx.module_context->current_meta_operation (mo_perform);
if (mo_perform.operation_pre != nullptr)
mo_perform.operation_pre ({} /* parameters */, update_id);
ctx.module_context->current_operation (op_update);
}
// "Switch" to the module context.
//
context& ctx (*bs.ctx.module_context);
// Load the imported project in the module context.
//
pair<names, const scope&> lr (import_load (ctx, move (ir), loc));
l5 ([&]{trace << "loaded " << lr.first;});
// When happens next depends on whether this is a top-level or nested
// module update.
//
if (nested)
{
// This could be initial or exclusive load.
//
// @@ TODO
//
fail (loc) << "nested build system module updates not yet supported";
}
else
{
const scope& rs (lr.second);
action_targets tgs;
action a (perform_id, update_id);
{
// Cutoff the existing diagnostics stack and push our own entry.
//
diag_frame::stack_guard diag_cutoff (nullptr);
auto df = make_diag_frame (
[&loc, &mod](const diag_record& dr)
{
dr << info (loc) << "while loading build system module " << mod;
});
// Note that for now we suppress progress since it would clash with
// the progress of what we are already doing (maybe in the future we
// can do save/restore but then we would need some sort of
// diagnostics that we have switched to another task).
//
mo_perform.search ({}, /* parameters */
rs, /* root scope */
rs, /* base scope */
path (), /* buildfile */
rs.find_target_key (lr.first, loc),
loc,
tgs);
mo_perform.match ({}, /* parameters */
a,
tgs,
1, /* diag (failures only) */
false /* progress */);
mo_perform.execute ({}, /* parameters */
a,
tgs,
1, /* diag (failures only) */
false /* progress */);
}
assert (tgs.size () == 1);
const target& l (tgs[0].as_target ());
if (!l.is_a ("libs"))
fail (loc) << "wrong export from build system module " << mod;
lib = l.as<file> ().path ();
l5 ([&]{trace << "updated " << lib;});
}
}
else
{
// No module project found. Form the shared library name (incorporating
// build system core version) and try using system-default search
// (installed, rpath, etc).
// @@ This is unfortunate: it would have been nice to do something
// similar to what we've done for exe{}. While libs{} is in the bin
// module, we could bring it in (we've done it for exe{}). The
// problems are: it is intertwined with its group (lib{}) and we
// don't have any mechanisms to deal with prefixes, only extensions.
//
const char* pfx;
const char* sfx;
#if defined(_WIN32)
pfx = "build2-"; sfx = ".dll";
#elif defined(__APPLE__)
pfx = "libbuild2-"; sfx = ".dylib";
#else
pfx = "libbuild2-"; sfx = ".so";
#endif
lib = path (pfx + mod + '-' + build_version_interface + sfx);
l5 ([&]{trace << "system-default search for " << lib;});
}
// The build2_<mod>_load() symbol name.
//
string sym (sanitize_identifier ("build2_" + mod + "_load"));
// Note that we don't unload our modules since it's not clear what would
// the benefit be.
//
diag_record dr;
#ifndef _WIN32
// Use RTLD_NOW instead of RTLD_LAZY to both speed things up (we are going
// to use this module now) and to detect any symbol mismatches.
//
if (void* h = dlopen (lib.string ().c_str (), RTLD_NOW | RTLD_GLOBAL))
{
r = function_cast<module_load_function*> (dlsym (h, sym.c_str ()));
// I don't think we should ignore this even if the module is optional.
//
if (r == nullptr)
fail (loc) << "unable to lookup " << sym << " in build system module "
<< mod << " (" << lib << "): " << dlerror ();
}
else if (!opt)
dr << fail (loc) << "unable to load build system module " << mod
<< " (" << lib << "): " << dlerror ();
else
l5 ([&]{trace << "unable to load " << lib << ": " << dlerror ();});
#else
if (HMODULE h = LoadLibrary (lib.string ().c_str ()))
{
r = function_cast<module_load_function*> (
GetProcAddress (h, sym.c_str ()));
if (r == nullptr)
fail (loc) << "unable to lookup " << sym << " in build system module "
<< mod << " (" << lib << "): " << win32::last_error_msg ();
}
else if (!opt)
dr << fail (loc) << "unable to load build system module " << mod
<< " (" << lib << "): " << win32::last_error_msg ();
else
l5 ([&]{trace << "unable to load " << lib << ": "
<< win32::last_error_msg ();});
#endif
// Add a suggestion similar to import phase 2.
//
if (!dr.empty ())
dr << info << "use config.import." << proj.variable () << " command "
<< "line variable to specify its project out_root" << endf;
#endif // BUILD2_BOOTSTRAP
return r;
}
static const module_functions*
find_module (scope& bs,
const string& smod,
const location& loc,
bool boot,
bool opt)
{
tracer trace ("find_module");
// Optional modules and submodules sure make this logic convoluted. So we
// divide it into two parts: (1) find or insert an entry (for submodule
// or, failed that, for the main module, the latter potentially NULL) and
// (2) analyze the entry and issue diagnostics.
//
auto i (loaded_modules.find (smod)), e (loaded_modules.end ());
if (i == e)
{
// If this is a submodule, get the main module name.
//
string mmod (smod, 0, smod.find ('.'));
if (mmod != smod)
i = loaded_modules.find (mmod);
if (i == e)
{
module_load_function* f (import_module (bs, mmod, loc, boot, opt));
if (f != nullptr)
{
// Enter all the entries noticing which one is our submodule. If
// none are, then we notice the main module.
//
for (const module_functions* j (f ()); j->name != nullptr; ++j)
{
const string& n (j->name);
l5 ([&]{trace << "registering " << n;});
auto p (loaded_modules.emplace (n, j));
if (!p.second)
fail (loc) << "build system submodule name " << n << " of main "
<< "module " << mmod << " is already in use";
if (n == smod || (i == e && n == mmod))
i = p.first;
}
// We should at least have the main module.
//
if (i == e)
fail (loc) << "invalid function list in build system module "
<< mmod;
}
else
i = loaded_modules.emplace (move (mmod), nullptr).first;
}
}
// Now the iterator points to a submodule or to the main module, the
// latter potentially NULL.
//
if (!opt)
{
if (i->second == nullptr)
{
fail (loc) << "unable to load build system module " << i->first;
}
else if (i->first != smod)
{
fail (loc) << "build system module " << i->first << " has no "
<< "submodule " << smod;
}
}
// Note that if the main module exists but has no such submodule, we
// return NULL rather than fail (think of an older version of a module
// that doesn't implement some extra functionality).
//
return i->second;
}
void
boot_module (scope& rs, const string& mod, const location& loc)
{
// First see if this modules has already been booted for this project.
//
module_map& lm (rs.root_extra->modules);
auto i (lm.find (mod));
if (i != lm.end ())
{
module_state& s (i->second);
// The only valid situation here is if the module has already been
// bootstrapped.
//
assert (s.boot);
return;
}
// Otherwise search for this module.
//
const module_functions& mf (
*find_module (rs, mod, loc, true /* boot */, false /* optional */));
if (mf.boot == nullptr)
fail (loc) << "build system module " << mod << " should not be loaded "
<< "during bootstrap";
i = lm.emplace (mod,
module_state {true, false, mf.init, nullptr, loc}).first;
i->second.first = mf.boot (rs, loc, i->second.module);
rs.assign (rs.ctx.var_pool.rw (rs).insert (mod + ".booted")) = true;
}
bool
init_module (scope& rs,
scope& bs,
const string& mod,
const location& loc,
bool opt,
const variable_map& hints)
{
// First see if this modules has already been inited for this project.
//
module_map& lm (rs.root_extra->modules);
auto i (lm.find (mod));
bool f (i == lm.end ());
if (f)
{
// Otherwise search for this module.
//
if (const module_functions* mf = find_module (
rs, mod, loc, false /* boot */, opt))
{
if (mf->boot != nullptr)
fail (loc) << "build system module " << mod << " should be loaded "
<< "during bootstrap";
i = lm.emplace (
mod,
module_state {false, false, mf->init, nullptr, loc}).first;
}
}
else
{
module_state& s (i->second);
if (s.boot)
{
s.boot = false;
f = true; // This is a first call to init.
}
}
// Note: pattern-typed in context ctor as project-visibility variables of
// type bool.
//
// We call the variable 'loaded' rather than 'inited' because it is
// buildfile-visible (where we use the term "load a module"; see the note
// on terminology above)
//
auto& vp (rs.ctx.var_pool.rw (rs));
value& lv (bs.assign (vp.insert (mod + ".loaded")));
value& cv (bs.assign (vp.insert (mod + ".configured")));
bool l; // Loaded (initialized).
bool c; // Configured.
// Suppress duplicate init() calls for the same module in the same scope.
//
if (!lv.null)
{
assert (!cv.null);
l = cast<bool> (lv);
c = cast<bool> (cv);
if (!opt)
{
if (!l)
fail (loc) << "unable to load build system module " << mod;
// We don't have original diagnostics. We could call init() again so
// that it can issue it. But that means optional modules must be
// prepared to be called again if configuring failed. Let's keep it
// simple for now.
//
if (!c)
fail (loc) << "build system module " << mod << " failed to "
<< "configure";
}
}
else
{
l = i != lm.end ();
c = l && i->second.init (rs, bs, loc, i->second.module, f, opt, hints);
lv = l;
cv = c;
}
return l && c;
}
}
|