xref: /openbsd-src/usr.bin/make/make.c (revision d13be5d47e4149db2549a9828e244d59dbc43f15)
1 /*	$OpenBSD: make.c,v 1.61 2010/07/19 19:46:44 espie Exp $	*/
2 /*	$NetBSD: make.c,v 1.10 1996/11/06 17:59:15 christos Exp $	*/
3 
4 /*
5  * Copyright (c) 1988, 1989, 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  * Copyright (c) 1989 by Berkeley Softworks
8  * All rights reserved.
9  *
10  * This code is derived from software contributed to Berkeley by
11  * Adam de Boor.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  */
37 
38 /*-
39  * make.c --
40  *	The functions which perform the examination of targets and
41  *	their suitability for creation
42  *
43  * Interface:
44  *	Make_Run		Initialize things for the module and recreate
45  *				whatever needs recreating. Returns true if
46  *				work was (or would have been) done and
47  *				false
48  *				otherwise.
49  *
50  *	Make_Update		Update all parents of a given child. Performs
51  *				various bookkeeping chores like the updating
52  *				of the cmtime field of the parent, filling
53  *				of the IMPSRC context variable, etc. It will
54  *				place the parent on the toBeMade queue if it
55  *				should be.
56  *
57  */
58 
59 #include <limits.h>
60 #include <stdio.h>
61 #include <signal.h>
62 #include <stddef.h>
63 #include <stdlib.h>
64 #include <string.h>
65 #include <ohash.h>
66 #include "config.h"
67 #include "defines.h"
68 #include "dir.h"
69 #include "job.h"
70 #include "suff.h"
71 #include "var.h"
72 #include "error.h"
73 #include "make.h"
74 #include "gnode.h"
75 #include "extern.h"
76 #include "timestamp.h"
77 #include "engine.h"
78 #include "lst.h"
79 #include "targ.h"
80 #include "targequiv.h"
81 #include "garray.h"
82 #include "memory.h"
83 
84 /* what gets added each time. Kept as one static array so that it doesn't
85  * get resized every time.
86  */
87 static struct growableArray examine;
88 /* The current fringe of the graph. These are nodes which await examination by
89  * MakeOODate. It is added to by Make_Update and subtracted from by
90  * MakeStartJobs */
91 static struct growableArray toBeMade;
92 
93 static struct ohash targets;	/* stuff we must build */
94 
95 static void MakeAddChild(void *, void *);
96 static void MakeHandleUse(void *, void *);
97 static bool MakeStartJobs(void);
98 static void MakePrintStatus(void *, void *);
99 static bool try_to_make_node(GNode *);
100 static void add_targets_to_make(Lst);
101 
102 static bool has_unmade_predecessor(GNode *);
103 static void requeue_successors(GNode *);
104 static void random_setup(void);
105 
106 static bool randomize_queue;
107 long random_delay = 0;
108 
109 bool
110 no_jobs_left()
111 {
112 	return Array_IsEmpty(&toBeMade);
113 }
114 
115 static void
116 random_setup()
117 {
118 	randomize_queue = Var_Definedi("RANDOM_ORDER", NULL);
119 
120 	if (Var_Definedi("RANDOM_DELAY", NULL))
121 		random_delay = strtonum(Var_Value("RANDOM_DELAY"), 0, 1000,
122 		    NULL) * 1000000;
123 
124 	if (randomize_queue || random_delay) {
125 		unsigned int random_seed;
126 		char *t;
127 
128 		t = Var_Value("RANDOM_SEED");
129 		if (t != NULL)
130 			random_seed = strtonum(t, 0, UINT_MAX, NULL);
131 		else
132 			random_seed = time(NULL);
133 		fprintf(stderr, "RANDOM_SEED=%u\n", random_seed);
134 		srandom(random_seed);
135 	}
136 }
137 
138 static void
139 randomize_garray(struct growableArray *g)
140 {
141 	/* This is a fairly standard algorithm to randomize an array. */
142 	unsigned int i, v;
143 	GNode *e;
144 
145 	for (i = g->n; i > 0; i--) {
146 		v = random() % i;
147 		if (v == i-1)
148 			continue;
149 		else {
150 			e = g->a[i-1];
151 			g->a[i-1] = g->a[v];
152 			g->a[v] = e;
153 		}
154 	}
155 }
156 
157 static bool
158 has_unmade_predecessor(GNode *gn)
159 {
160 	LstNode ln;
161 
162 	if (Lst_IsEmpty(&gn->preds))
163 		return false;
164 
165 
166 	for (ln = Lst_First(&gn->preds); ln != NULL; ln = Lst_Adv(ln)) {
167 		GNode	*pgn = (GNode *)Lst_Datum(ln);
168 
169 		if (pgn->must_make && pgn->built_status == UNKNOWN) {
170 			if (DEBUG(MAKE))
171 				printf("predecessor %s not made yet.\n",
172 				    pgn->name);
173 			return true;
174 		}
175 	}
176 	return false;
177 }
178 
179 static void
180 requeue_successors(GNode *gn)
181 {
182 	LstNode ln;
183 	/* Deal with successor nodes. If any is marked for making and has an
184 	 * unmade count of 0, has not been made and isn't in the examination
185 	 * queue, it means we need to place it in the queue as it restrained
186 	 * itself before.	*/
187 	for (ln = Lst_First(&gn->successors); ln != NULL; ln = Lst_Adv(ln)) {
188 		GNode	*succ = (GNode *)Lst_Datum(ln);
189 
190 		if (succ->must_make && succ->unmade == 0
191 		    && succ->built_status == UNKNOWN)
192 			Array_PushNew(&toBeMade, succ);
193 	}
194 }
195 
196 /*-
197  *-----------------------------------------------------------------------
198  * Make_Update	--
199  *	Perform update on the parents of a node. Used by JobFinish once
200  *	a node has been dealt with and by MakeStartJobs if it finds an
201  *	up-to-date node.
202  *
203  * Results:
204  *	Always returns 0
205  *
206  * Side Effects:
207  *	The unmade field of pgn is decremented and pgn may be placed on
208  *	the toBeMade queue if this field becomes 0.
209  *
210  *	If the child was made, the parent's childMade field will be set true
211  *	and its cmtime set to now.
212  *
213  *	If the child wasn't made, the cmtime field of the parent will be
214  *	altered if the child's mtime is big enough.
215  *
216  *-----------------------------------------------------------------------
217  */
218 void
219 Make_Update(GNode *cgn)	/* the child node */
220 {
221 	GNode	*pgn;	/* the parent node */
222 	char	*cname; /* the child's name */
223 	LstNode	ln;	/* Element in parents list */
224 
225 	cname = Var(TARGET_INDEX, cgn);
226 
227 	/*
228 	 * If the child was actually made, see what its modification time is
229 	 * now -- some rules won't actually update the file. If the file still
230 	 * doesn't exist, make its mtime now.
231 	 */
232 	if (cgn->built_status != UPTODATE) {
233 		/*
234 		 * This is what Make does and it's actually a good thing, as it
235 		 * allows rules like
236 		 *
237 		 *	cmp -s y.tab.h parse.h || cp y.tab.h parse.h
238 		 *
239 		 * to function as intended. Unfortunately, thanks to the
240 		 * stateless nature of NFS, there are times when the
241 		 * modification time of a file created on a remote machine
242 		 * will not be modified before the local stat() implied by
243 		 * the Dir_MTime occurs, thus leading us to believe that the
244 		 * file is unchanged, wreaking havoc with files that depend
245 		 * on this one.
246 		 */
247 		if (noExecute || is_out_of_date(Dir_MTime(cgn)))
248 			ts_set_from_now(cgn->mtime);
249 		if (DEBUG(MAKE))
250 			printf("update time: %s\n", time_to_string(cgn->mtime));
251 	}
252 
253 	/* SIB: this is where I should mark the build as finished */
254 	cgn->build_lock = false;
255 	for (ln = Lst_First(&cgn->parents); ln != NULL; ln = Lst_Adv(ln)) {
256 		pgn = (GNode *)Lst_Datum(ln);
257 		/* SIB: there should be a siblings loop there */
258 		pgn->unmade--;
259 		if (pgn->must_make) {
260 			if (DEBUG(MAKE))
261 				printf("%s--=%d ",
262 				    pgn->name, pgn->unmade);
263 
264 			if ( ! (cgn->type & (OP_EXEC|OP_USE))) {
265 				if (cgn->built_status == MADE) {
266 					pgn->childMade = true;
267 					if (is_strictly_before(pgn->cmtime,
268 					    cgn->mtime))
269 						pgn->cmtime = cgn->mtime;
270 				} else {
271 					(void)Make_TimeStamp(pgn, cgn);
272 				}
273 			}
274 			if (pgn->unmade == 0) {
275 				/*
276 				 * Queue the node up -- any unmade
277 				 * predecessors will be dealt with in
278 				 * MakeStartJobs.
279 				 */
280 				if (DEBUG(MAKE))
281 					printf("QUEUING ");
282 				Array_Push(&toBeMade, pgn);
283 			} else if (pgn->unmade < 0) {
284 				Error("Child %s discovered graph cycles through %s", cgn->name, pgn->name);
285 			}
286 		}
287 	}
288 	if (DEBUG(MAKE))
289 		printf("\n");
290 	requeue_successors(cgn);
291 }
292 
293 static bool
294 try_to_make_node(GNode *gn)
295 {
296 	if (DEBUG(MAKE))
297 		printf("Examining %s...", gn->name);
298 
299 	if (gn->unmade != 0) {
300 		if (DEBUG(MAKE))
301 			printf(" Requeuing (%d)\n", gn->unmade);
302 		add_targets_to_make(&gn->children);
303 		Array_Push(&toBeMade, gn);
304 		return false;
305 	}
306 	if (has_been_built(gn)) {
307 		if (DEBUG(MAKE))
308 			printf(" already made\n");
309 			return false;
310 	}
311 	if (has_unmade_predecessor(gn)) {
312 		if (DEBUG(MAKE))
313 			printf(" Dropping for now\n");
314 		return false;
315 	}
316 
317 	/* SIB: this is where there should be a siblings loop */
318 	Suff_FindDeps(gn);
319 	if (gn->unmade != 0) {
320 		if (DEBUG(MAKE))
321 			printf(" Requeuing (after deps: %d)\n", gn->unmade);
322 		add_targets_to_make(&gn->children);
323 		return false;
324 	}
325 	if (Make_OODate(gn)) {
326 		/* SIB: if a sibling is getting built, I don't build it right now */
327 		if (DEBUG(MAKE))
328 			printf("out-of-date\n");
329 		if (queryFlag)
330 			return true;
331 		/* SIB: this is where commands should get prepared */
332 		Make_DoAllVar(gn);
333 		/* SIB: this is where I should make the gn as `being built */
334 		gn->build_lock = true;
335 		Job_Make(gn);
336 	} else {
337 		if (DEBUG(MAKE))
338 			printf("up-to-date\n");
339 		gn->built_status = UPTODATE;
340 		if (gn->type & OP_JOIN) {
341 			/*
342 			 * Even for an up-to-date .JOIN node, we need it
343 			 * to have its context variables so references
344 			 * to it get the correct value for .TARGET when
345 			 * building up the context variables of its
346 			 * parent(s)...
347 			 */
348 			Make_DoAllVar(gn);
349 		}
350 
351 		Make_Update(gn);
352 	}
353 	return false;
354 }
355 
356 /*
357  *-----------------------------------------------------------------------
358  * MakeStartJobs --
359  *	Start as many jobs as possible.
360  *
361  * Results:
362  *	If the query flag was given to pmake, no job will be started,
363  *	but as soon as an out-of-date target is found, this function
364  *	returns true. At all other times, this function returns false.
365  *
366  * Side Effects:
367  *	Nodes are removed from the toBeMade queue and job table slots
368  *	are filled.
369  *-----------------------------------------------------------------------
370  */
371 static bool
372 MakeStartJobs(void)
373 {
374 	GNode	*gn;
375 
376 	while (can_start_job() && (gn = Array_Pop(&toBeMade)) != NULL) {
377 		if (try_to_make_node(gn))
378 			return true;
379 	}
380 	return false;
381 }
382 
383 /*-
384  *-----------------------------------------------------------------------
385  * MakePrintStatus --
386  *	Print the status of a top-level node, viz. it being up-to-date
387  *	already or not created due to an error in a lower level.
388  *	Callback function for Make_Run via Lst_ForEach.
389  *
390  * Side Effects:
391  *	A message may be printed.
392  *-----------------------------------------------------------------------
393  */
394 static void
395 MakePrintStatus(
396     void *gnp,		    /* Node to examine */
397     void *cyclep)	    /* True if gn->unmade being non-zero implies
398 			     * a cycle in the graph, not an error in an
399 			     * inferior */
400 {
401 	GNode	*gn = (GNode *)gnp;
402 	bool	cycle = *(bool *)cyclep;
403 	if (gn->built_status == UPTODATE) {
404 		printf("`%s' is up to date.\n", gn->name);
405 	} else if (gn->unmade != 0) {
406 		if (cycle) {
407 			bool t = true;
408 			/*
409 			 * If printing cycles and came to one that has unmade
410 			 * children, print out the cycle by recursing on its
411 			 * children. Note a cycle like:
412 			 *	a : b
413 			 *	b : c
414 			 *	c : b
415 			 * will cause this to erroneously complain about a
416 			 * being in the cycle, but this is a good approximation.
417 			 */
418 			if (gn->built_status == CYCLE) {
419 				Error("Graph cycles through `%s'", gn->name);
420 				gn->built_status = ENDCYCLE;
421 				Lst_ForEach(&gn->children, MakePrintStatus, &t);
422 				gn->built_status = UNKNOWN;
423 			} else if (gn->built_status != ENDCYCLE) {
424 				gn->built_status = CYCLE;
425 				Lst_ForEach(&gn->children, MakePrintStatus, &t);
426 			}
427 		} else {
428 			printf("`%s' not remade because of errors.\n",
429 			    gn->name);
430 		}
431 	}
432 }
433 
434 
435 static void
436 MakeAddChild(void *to_addp, void *ap)
437 {
438 	GNode *gn = (GNode *)to_addp;
439 
440 	if (!gn->must_make && !(gn->type & OP_USE))
441 		Array_Push((struct growableArray *)ap, gn);
442 }
443 
444 static void
445 MakeHandleUse(void *cgnp, void *pgnp)
446 {
447 	GNode *cgn = (GNode *)cgnp;
448 	GNode *pgn = (GNode *)pgnp;
449 
450 	if (cgn->type & OP_USE)
451 		Make_HandleUse(cgn, pgn);
452 }
453 
454 /* Add stuff to the toBeMade queue. we try to sort things so that stuff
455  * that can be done directly is done right away.  This won't be perfect,
456  * since some dependencies are only discovered later (e.g., SuffFindDeps).
457  */
458 static void
459 add_targets_to_make(Lst todo)
460 {
461 	GNode *gn;
462 
463 	unsigned int slot;
464 
465 	AppendList2Array(todo, &examine);
466 
467 	while ((gn = Array_Pop(&examine)) != NULL) {
468 		if (gn->must_make) 	/* already known */
469 			continue;
470 		gn->must_make = true;
471 
472 		slot = ohash_qlookup(&targets, gn->name);
473 		if (!ohash_find(&targets, slot))
474 			ohash_insert(&targets, slot, gn);
475 
476 
477 		look_harder_for_target(gn);
478 		kludge_look_harder_for_target(gn);
479 		/*
480 		 * Apply any .USE rules before looking for implicit
481 		 * dependencies to make sure everything that should have
482 		 * commands has commands ...
483 		 */
484 		Lst_ForEach(&gn->children, MakeHandleUse, gn);
485 		expand_all_children(gn);
486 
487 		if (gn->unmade != 0) {
488 			if (DEBUG(MAKE))
489 				printf("%s: not queuing (%d unmade children)\n",
490 				    gn->name, gn->unmade);
491 			Lst_ForEach(&gn->children, MakeAddChild,
492 			    &examine);
493 		} else {
494 			if (DEBUG(MAKE))
495 				printf("%s: queuing\n", gn->name);
496 			Array_Push(&toBeMade, gn);
497 		}
498 	}
499 	if (randomize_queue)
500 		randomize_garray(&toBeMade);
501 }
502 
503 /*-
504  *-----------------------------------------------------------------------
505  * Make_Run --
506  *	Initialize the nodes to remake and the list of nodes which are
507  *	ready to be made by doing a breadth-first traversal of the graph
508  *	starting from the nodes in the given list. Once this traversal
509  *	is finished, all the 'leaves' of the graph are in the toBeMade
510  *	queue.
511  *	Using this queue and the Job module, work back up the graph,
512  *	calling on MakeStartJobs to keep the job table as full as
513  *	possible.
514  *
515  * Results:
516  *	true if work was done. false otherwise.
517  *
518  * Side Effects:
519  *	The must_make field of all nodes involved in the creation of the given
520  *	targets is set to 1. The toBeMade list is set to contain all the
521  *	'leaves' of these subgraphs.
522  *-----------------------------------------------------------------------
523  */
524 bool
525 Make_Run(Lst targs)		/* the initial list of targets */
526 {
527 	int errors;	/* Number of errors the Job module reports */
528 	GNode *gn;
529 	unsigned int i;
530 	bool cycle;
531 
532 	/* wild guess at initial sizes */
533 	Array_Init(&toBeMade, 500);
534 	Array_Init(&examine, 150);
535 	ohash_init(&targets, 10, &gnode_info);
536 	if (DEBUG(PARALLEL))
537 		random_setup();
538 
539 	add_targets_to_make(targs);
540 	if (queryFlag) {
541 		/*
542 		 * We wouldn't do any work unless we could start some jobs in
543 		 * the next loop... (we won't actually start any, of course,
544 		 * this is just to see if any of the targets was out of date)
545 		 */
546 		return MakeStartJobs();
547 	} else {
548 		/*
549 		 * Initialization. At the moment, no jobs are running and until
550 		 * some get started, nothing will happen since the remaining
551 		 * upward traversal of the graph is performed by the routines
552 		 * in job.c upon the finishing of a job. So we fill the Job
553 		 * table as much as we can before going into our loop.
554 		 */
555 		(void)MakeStartJobs();
556 	}
557 
558 	/*
559 	 * Main Loop: The idea here is that the ending of jobs will take
560 	 * care of the maintenance of data structures and the waiting for output
561 	 * will cause us to be idle most of the time while our children run as
562 	 * much as possible. Because the job table is kept as full as possible,
563 	 * the only time when it will be empty is when all the jobs which need
564 	 * running have been run, so that is the end condition of this loop.
565 	 * Note that the Job module will exit if there were any errors unless
566 	 * the keepgoing flag was given.
567 	 */
568 	while (!Job_Empty()) {
569 		handle_running_jobs();
570 		(void)MakeStartJobs();
571 	}
572 
573 	errors = Job_Finish();
574 	cycle = false;
575 
576 	for (gn = ohash_first(&targets, &i); gn != NULL;
577 	    gn = ohash_next(&targets, &i)) {
578 	    	if (has_been_built(gn))
579 			continue;
580 		cycle = true;
581 		errors++;
582 	    	printf("Error: target %s unaccounted for (%s)\n",
583 		    gn->name, status_to_string(gn));
584 	}
585 	/*
586 	 * Print the final status of each target. E.g. if it wasn't made
587 	 * because some inferior reported an error.
588 	 */
589 	Lst_ForEach(targs, MakePrintStatus, &cycle);
590 	if (errors)
591 		Fatal("Errors while building");
592 
593 	return true;
594 }
595