xref: /freebsd/contrib/bmake/meta.c (revision 98e0ffaefb0f241cda3a72395d3be04192ae0d47)
1 /*      $NetBSD: meta.c,v 1.38 2015/04/11 05:24:30 sjg Exp $ */
2 
3 /*
4  * Implement 'meta' mode.
5  * Adapted from John Birrell's patches to FreeBSD make.
6  * --sjg
7  */
8 /*
9  * Copyright (c) 2009-2010, Juniper Networks, Inc.
10  * Portions Copyright (c) 2009, John Birrell.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 #if defined(USE_META)
34 
35 #ifdef HAVE_CONFIG_H
36 # include "config.h"
37 #endif
38 #include <sys/stat.h>
39 #include <sys/ioctl.h>
40 #include <fcntl.h>
41 #include <libgen.h>
42 #include <errno.h>
43 #if !defined(HAVE_CONFIG_H) || defined(HAVE_ERR_H)
44 #include <err.h>
45 #endif
46 
47 #include "make.h"
48 #include "job.h"
49 
50 #ifdef HAVE_FILEMON_H
51 # include <filemon.h>
52 #endif
53 #if !defined(USE_FILEMON) && defined(FILEMON_SET_FD)
54 # define USE_FILEMON
55 #endif
56 
57 static BuildMon Mybm;			/* for compat */
58 static Lst metaBailiwick;		/* our scope of control */
59 static Lst metaIgnorePaths;		/* paths we deliberately ignore */
60 
61 #ifndef MAKE_META_IGNORE_PATHS
62 #define MAKE_META_IGNORE_PATHS ".MAKE.META.IGNORE_PATHS"
63 #endif
64 
65 Boolean useMeta = FALSE;
66 static Boolean useFilemon = FALSE;
67 static Boolean writeMeta = FALSE;
68 static Boolean metaEnv = FALSE;		/* don't save env unless asked */
69 static Boolean metaVerbose = FALSE;
70 static Boolean metaIgnoreCMDs = FALSE;	/* ignore CMDs in .meta files */
71 static Boolean metaCurdirOk = FALSE;	/* write .meta in .CURDIR Ok? */
72 static Boolean metaSilent = FALSE;	/* if we have a .meta be SILENT */
73 
74 extern Boolean forceJobs;
75 extern Boolean comatMake;
76 extern char    **environ;
77 
78 #define	MAKE_META_PREFIX	".MAKE.META.PREFIX"
79 
80 #ifndef N2U
81 # define N2U(n, u)   (((n) + ((u) - 1)) / (u))
82 #endif
83 #ifndef ROUNDUP
84 # define ROUNDUP(n, u)   (N2U((n), (u)) * (u))
85 #endif
86 
87 #if !defined(HAVE_STRSEP)
88 # define strsep(s, d) stresep((s), (d), 0)
89 #endif
90 
91 /*
92  * Filemon is a kernel module which snoops certain syscalls.
93  *
94  * C chdir
95  * E exec
96  * F [v]fork
97  * L [sym]link
98  * M rename
99  * R read
100  * W write
101  * S stat
102  *
103  * See meta_oodate below - we mainly care about 'E' and 'R'.
104  *
105  * We can still use meta mode without filemon, but
106  * the benefits are more limited.
107  */
108 #ifdef USE_FILEMON
109 # ifndef _PATH_FILEMON
110 #   define _PATH_FILEMON "/dev/filemon"
111 # endif
112 
113 /*
114  * Open the filemon device.
115  */
116 static void
117 filemon_open(BuildMon *pbm)
118 {
119     int retry;
120 
121     pbm->mon_fd = pbm->filemon_fd = -1;
122     if (!useFilemon)
123 	return;
124 
125     for (retry = 5; retry >= 0; retry--) {
126 	if ((pbm->filemon_fd = open(_PATH_FILEMON, O_RDWR)) >= 0)
127 	    break;
128     }
129 
130     if (pbm->filemon_fd < 0) {
131 	useFilemon = FALSE;
132 	warn("Could not open %s", _PATH_FILEMON);
133 	return;
134     }
135 
136     /*
137      * We use a file outside of '.'
138      * to avoid a FreeBSD kernel bug where unlink invalidates
139      * cwd causing getcwd to do a lot more work.
140      * We only care about the descriptor.
141      */
142     pbm->mon_fd = mkTempFile("filemon.XXXXXX", NULL);
143     if (ioctl(pbm->filemon_fd, FILEMON_SET_FD, &pbm->mon_fd) < 0) {
144 	err(1, "Could not set filemon file descriptor!");
145     }
146     /* we don't need these once we exec */
147     (void)fcntl(pbm->mon_fd, F_SETFD, 1);
148     (void)fcntl(pbm->filemon_fd, F_SETFD, 1);
149 }
150 
151 /*
152  * Read the build monitor output file and write records to the target's
153  * metadata file.
154  */
155 static void
156 filemon_read(FILE *mfp, int fd)
157 {
158     char buf[BUFSIZ];
159     int n;
160 
161     /* Check if we're not writing to a meta data file.*/
162     if (mfp == NULL) {
163 	if (fd >= 0)
164 	    close(fd);			/* not interested */
165 	return;
166     }
167     /* rewind */
168     (void)lseek(fd, (off_t)0, SEEK_SET);
169 
170     fprintf(mfp, "\n-- filemon acquired metadata --\n");
171 
172     while ((n = read(fd, buf, sizeof(buf))) > 0) {
173 	fwrite(buf, 1, n, mfp);
174     }
175     fflush(mfp);
176     close(fd);
177 }
178 #endif
179 
180 /*
181  * when realpath() fails,
182  * we use this, to clean up ./ and ../
183  */
184 static void
185 eat_dots(char *buf, size_t bufsz, int dots)
186 {
187     char *cp;
188     char *cp2;
189     const char *eat;
190     size_t eatlen;
191 
192     switch (dots) {
193     case 1:
194 	eat = "/./";
195 	eatlen = 2;
196 	break;
197     case 2:
198 	eat = "/../";
199 	eatlen = 3;
200 	break;
201     default:
202 	return;
203     }
204 
205     do {
206 	cp = strstr(buf, eat);
207 	if (cp) {
208 	    cp2 = cp + eatlen;
209 	    if (dots == 2 && cp > buf) {
210 		do {
211 		    cp--;
212 		} while (cp > buf && *cp != '/');
213 	    }
214 	    if (*cp == '/') {
215 		strlcpy(cp, cp2, bufsz - (cp - buf));
216 	    } else {
217 		return;			/* can't happen? */
218 	    }
219 	}
220     } while (cp);
221 }
222 
223 static char *
224 meta_name(struct GNode *gn, char *mname, size_t mnamelen,
225 	  const char *dname,
226 	  const char *tname)
227 {
228     char buf[MAXPATHLEN];
229     char cwd[MAXPATHLEN];
230     char *rp;
231     char *cp;
232     char *tp;
233     char *p[4];				/* >= number of possible uses */
234     int i;
235 
236     i = 0;
237     if (!dname)
238 	dname = Var_Value(".OBJDIR", gn, &p[i++]);
239     if (!tname)
240 	tname = Var_Value(TARGET, gn, &p[i++]);
241 
242     if (realpath(dname, cwd))
243 	dname = cwd;
244 
245     /*
246      * Weed out relative paths from the target file name.
247      * We have to be careful though since if target is a
248      * symlink, the result will be unstable.
249      * So we use realpath() just to get the dirname, and leave the
250      * basename as given to us.
251      */
252     if ((cp = strrchr(tname, '/'))) {
253 	if (realpath(tname, buf)) {
254 	    if ((rp = strrchr(buf, '/'))) {
255 		rp++;
256 		cp++;
257 		if (strcmp(cp, rp) != 0)
258 		    strlcpy(rp, cp, sizeof(buf) - (rp - buf));
259 	    }
260 	    tname = buf;
261 	} else {
262 	    /*
263 	     * We likely have a directory which is about to be made.
264 	     * We pretend realpath() succeeded, to have a chance
265 	     * of generating the same meta file name that we will
266 	     * next time through.
267 	     */
268 	    if (tname[0] == '/') {
269 		strlcpy(buf, tname, sizeof(buf));
270 	    } else {
271 		snprintf(buf, sizeof(buf), "%s/%s", cwd, tname);
272 	    }
273 	    eat_dots(buf, sizeof(buf), 1);	/* ./ */
274 	    eat_dots(buf, sizeof(buf), 2);	/* ../ */
275 	    tname = buf;
276 	}
277     }
278     /* on some systems dirname may modify its arg */
279     tp = bmake_strdup(tname);
280     if (strcmp(dname, dirname(tp)) == 0)
281 	snprintf(mname, mnamelen, "%s.meta", tname);
282     else {
283 	snprintf(mname, mnamelen, "%s/%s.meta", dname, tname);
284 
285 	/*
286 	 * Replace path separators in the file name after the
287 	 * current object directory path.
288 	 */
289 	cp = mname + strlen(dname) + 1;
290 
291 	while (*cp != '\0') {
292 	    if (*cp == '/')
293 		*cp = '_';
294 	    cp++;
295 	}
296     }
297     free(tp);
298     for (i--; i >= 0; i--) {
299 	if (p[i])
300 	    free(p[i]);
301     }
302     return (mname);
303 }
304 
305 /*
306  * Return true if running ${.MAKE}
307  * Bypassed if target is flagged .MAKE
308  */
309 static int
310 is_submake(void *cmdp, void *gnp)
311 {
312     static char *p_make = NULL;
313     static int p_len;
314     char  *cmd = cmdp;
315     GNode *gn = gnp;
316     char *mp = NULL;
317     char *cp;
318     char *cp2;
319     int rc = 0;				/* keep looking */
320 
321     if (!p_make) {
322 	p_make = Var_Value(".MAKE", gn, &cp);
323 	p_len = strlen(p_make);
324     }
325     cp = strchr(cmd, '$');
326     if ((cp)) {
327 	mp = Var_Subst(NULL, cmd, gn, FALSE);
328 	cmd = mp;
329     }
330     cp2 = strstr(cmd, p_make);
331     if ((cp2)) {
332 	switch (cp2[p_len]) {
333 	case '\0':
334 	case ' ':
335 	case '\t':
336 	case '\n':
337 	    rc = 1;
338 	    break;
339 	}
340 	if (cp2 > cmd && rc > 0) {
341 	    switch (cp2[-1]) {
342 	    case ' ':
343 	    case '\t':
344 	    case '\n':
345 		break;
346 	    default:
347 		rc = 0;			/* no match */
348 		break;
349 	    }
350 	}
351     }
352     if (mp)
353 	free(mp);
354     return (rc);
355 }
356 
357 typedef struct meta_file_s {
358     FILE *fp;
359     GNode *gn;
360 } meta_file_t;
361 
362 static int
363 printCMD(void *cmdp, void *mfpp)
364 {
365     meta_file_t *mfp = mfpp;
366     char *cmd = cmdp;
367     char *cp = NULL;
368 
369     if (strchr(cmd, '$')) {
370 	cmd = cp = Var_Subst(NULL, cmd, mfp->gn, FALSE);
371     }
372     fprintf(mfp->fp, "CMD %s\n", cmd);
373     if (cp)
374 	free(cp);
375     return 0;
376 }
377 
378 /*
379  * Certain node types never get a .meta file
380  */
381 #define SKIP_META_TYPE(_type) do { \
382     if ((gn->type & __CONCAT(OP_, _type))) {	\
383 	if (DEBUG(META)) { \
384 	    fprintf(debug_file, "Skipping meta for %s: .%s\n", \
385 		    gn->name, __STRING(_type));		       \
386 	} \
387 	return (NULL); \
388     } \
389 } while (0)
390 
391 static FILE *
392 meta_create(BuildMon *pbm, GNode *gn)
393 {
394     meta_file_t mf;
395     char buf[MAXPATHLEN];
396     char objdir[MAXPATHLEN];
397     char **ptr;
398     const char *dname;
399     const char *tname;
400     char *fname;
401     const char *cp;
402     char *p[4];				/* >= possible uses */
403     int i;
404     struct stat fs;
405 
406 
407     /* This may be a phony node which we don't want meta data for... */
408     /* Skip .meta for .BEGIN, .END, .ERROR etc as well. */
409     /* Or it may be explicitly flagged as .NOMETA */
410     SKIP_META_TYPE(NOMETA);
411     /* Unless it is explicitly flagged as .META */
412     if (!(gn->type & OP_META)) {
413 	SKIP_META_TYPE(PHONY);
414 	SKIP_META_TYPE(SPECIAL);
415 	SKIP_META_TYPE(MAKE);
416     }
417 
418     mf.fp = NULL;
419 
420     i = 0;
421 
422     dname = Var_Value(".OBJDIR", gn, &p[i++]);
423     tname = Var_Value(TARGET, gn, &p[i++]);
424 
425     /* The object directory may not exist. Check it.. */
426     if (stat(dname, &fs) != 0) {
427 	if (DEBUG(META))
428 	    fprintf(debug_file, "Skipping meta for %s: no .OBJDIR\n",
429 		    gn->name);
430 	goto out;
431     }
432     /* Check if there are no commands to execute. */
433     if (Lst_IsEmpty(gn->commands)) {
434 	if (DEBUG(META))
435 	    fprintf(debug_file, "Skipping meta for %s: no commands\n",
436 		    gn->name);
437 	goto out;
438     }
439 
440     /* make sure these are canonical */
441     if (realpath(dname, objdir))
442 	dname = objdir;
443 
444     /* If we aren't in the object directory, don't create a meta file. */
445     if (!metaCurdirOk && strcmp(curdir, dname) == 0) {
446 	if (DEBUG(META))
447 	    fprintf(debug_file, "Skipping meta for %s: .OBJDIR == .CURDIR\n",
448 		    gn->name);
449 	goto out;
450     }
451     if (!(gn->type & OP_META)) {
452 	/* We do not generate .meta files for sub-makes */
453 	if (Lst_ForEach(gn->commands, is_submake, gn)) {
454 	    if (DEBUG(META))
455 		fprintf(debug_file, "Skipping meta for %s: .MAKE\n",
456 			gn->name);
457 	    goto out;
458 	}
459     }
460 
461     if (metaVerbose) {
462 	char *mp;
463 
464 	/* Describe the target we are building */
465 	mp = Var_Subst(NULL, "${" MAKE_META_PREFIX "}", gn, 0);
466 	if (*mp)
467 	    fprintf(stdout, "%s\n", mp);
468 	free(mp);
469     }
470     /* Get the basename of the target */
471     if ((cp = strrchr(tname, '/')) == NULL) {
472 	cp = tname;
473     } else {
474 	cp++;
475     }
476 
477     fflush(stdout);
478 
479     if (strcmp(cp, makeDependfile) == 0)
480 	goto out;
481 
482     if (!writeMeta)
483 	/* Don't create meta data. */
484 	goto out;
485 
486     fname = meta_name(gn, pbm->meta_fname, sizeof(pbm->meta_fname),
487 		      dname, tname);
488 
489 #ifdef DEBUG_META_MODE
490     if (DEBUG(META))
491 	fprintf(debug_file, "meta_create: %s\n", fname);
492 #endif
493 
494     if ((mf.fp = fopen(fname, "w")) == NULL)
495 	err(1, "Could not open meta file '%s'", fname);
496 
497     fprintf(mf.fp, "# Meta data file %s\n", fname);
498 
499     mf.gn = gn;
500 
501     Lst_ForEach(gn->commands, printCMD, &mf);
502 
503     fprintf(mf.fp, "CWD %s\n", getcwd(buf, sizeof(buf)));
504     fprintf(mf.fp, "TARGET %s\n", tname);
505 
506     if (metaEnv) {
507 	for (ptr = environ; *ptr != NULL; ptr++)
508 	    fprintf(mf.fp, "ENV %s\n", *ptr);
509     }
510 
511     fprintf(mf.fp, "-- command output --\n");
512     fflush(mf.fp);
513 
514     Var_Append(".MAKE.META.FILES", fname, VAR_GLOBAL);
515     Var_Append(".MAKE.META.CREATED", fname, VAR_GLOBAL);
516 
517     gn->type |= OP_META;		/* in case anyone wants to know */
518     if (metaSilent) {
519 	    gn->type |= OP_SILENT;
520     }
521  out:
522     for (i--; i >= 0; i--) {
523 	if (p[i])
524 	    free(p[i]);
525     }
526 
527     return (mf.fp);
528 }
529 
530 static Boolean
531 boolValue(char *s)
532 {
533     switch(*s) {
534     case '0':
535     case 'N':
536     case 'n':
537     case 'F':
538     case 'f':
539 	return FALSE;
540     }
541     return TRUE;
542 }
543 
544 /*
545  * Initialization we need before reading makefiles.
546  */
547 void
548 meta_init(void)
549 {
550 #ifdef USE_FILEMON
551 	/* this allows makefiles to test if we have filemon support */
552 	Var_Set(".MAKE.PATH_FILEMON", _PATH_FILEMON, VAR_GLOBAL, 0);
553 #endif
554 }
555 
556 
557 /*
558  * Initialization we need after reading makefiles.
559  */
560 void
561 meta_mode_init(const char *make_mode)
562 {
563     static int once = 0;
564     char *cp;
565 
566     useMeta = TRUE;
567     useFilemon = TRUE;
568     writeMeta = TRUE;
569 
570     if (make_mode) {
571 	if (strstr(make_mode, "env"))
572 	    metaEnv = TRUE;
573 	if (strstr(make_mode, "verb"))
574 	    metaVerbose = TRUE;
575 	if (strstr(make_mode, "read"))
576 	    writeMeta = FALSE;
577 	if (strstr(make_mode, "nofilemon"))
578 	    useFilemon = FALSE;
579 	if ((cp = strstr(make_mode, "curdirok="))) {
580 	    metaCurdirOk = boolValue(&cp[9]);
581 	}
582 	if ((cp = strstr(make_mode, "silent="))) {
583 	    metaSilent = boolValue(&cp[7]);
584 	}
585 	if (strstr(make_mode, "ignore-cmd"))
586 	    metaIgnoreCMDs = TRUE;
587 	/* for backwards compatability */
588 	Var_Set(".MAKE.META_CREATED", "${.MAKE.META.CREATED}", VAR_GLOBAL, 0);
589 	Var_Set(".MAKE.META_FILES", "${.MAKE.META.FILES}", VAR_GLOBAL, 0);
590     }
591     if (metaVerbose && !Var_Exists(MAKE_META_PREFIX, VAR_GLOBAL)) {
592 	/*
593 	 * The default value for MAKE_META_PREFIX
594 	 * prints the absolute path of the target.
595 	 * This works be cause :H will generate '.' if there is no /
596 	 * and :tA will resolve that to cwd.
597 	 */
598 	Var_Set(MAKE_META_PREFIX, "Building ${.TARGET:H:tA}/${.TARGET:T}", VAR_GLOBAL, 0);
599     }
600     if (once)
601 	return;
602     once = 1;
603     memset(&Mybm, 0, sizeof(Mybm));
604     /*
605      * We consider ourselves master of all within ${.MAKE.META.BAILIWICK}
606      */
607     metaBailiwick = Lst_Init(FALSE);
608     cp = Var_Subst(NULL, "${.MAKE.META.BAILIWICK:O:u:tA}", VAR_GLOBAL, 0);
609     if (cp) {
610 	str2Lst_Append(metaBailiwick, cp, NULL);
611     }
612     /*
613      * We ignore any paths that start with ${.MAKE.META.IGNORE_PATHS}
614      */
615     metaIgnorePaths = Lst_Init(FALSE);
616     Var_Append(MAKE_META_IGNORE_PATHS,
617 	       "/dev /etc /proc /tmp /var/run /var/tmp ${TMPDIR}", VAR_GLOBAL);
618     cp = Var_Subst(NULL,
619 		   "${" MAKE_META_IGNORE_PATHS ":O:u:tA}", VAR_GLOBAL, 0);
620     if (cp) {
621 	str2Lst_Append(metaIgnorePaths, cp, NULL);
622     }
623 }
624 
625 /*
626  * In each case below we allow for job==NULL
627  */
628 void
629 meta_job_start(Job *job, GNode *gn)
630 {
631     BuildMon *pbm;
632 
633     if (job != NULL) {
634 	pbm = &job->bm;
635     } else {
636 	pbm = &Mybm;
637     }
638     pbm->mfp = meta_create(pbm, gn);
639 #ifdef USE_FILEMON_ONCE
640     /* compat mode we open the filemon dev once per command */
641     if (job == NULL)
642 	return;
643 #endif
644 #ifdef USE_FILEMON
645     if (pbm->mfp != NULL && useFilemon) {
646 	filemon_open(pbm);
647     } else {
648 	pbm->mon_fd = pbm->filemon_fd = -1;
649     }
650 #endif
651 }
652 
653 /*
654  * The child calls this before doing anything.
655  * It does not disturb our state.
656  */
657 void
658 meta_job_child(Job *job)
659 {
660 #ifdef USE_FILEMON
661     BuildMon *pbm;
662 
663     if (job != NULL) {
664 	pbm = &job->bm;
665     } else {
666 	pbm = &Mybm;
667     }
668     if (pbm->mfp != NULL) {
669 	close(fileno(pbm->mfp));
670 	if (useFilemon) {
671 	    pid_t pid;
672 
673 	    pid = getpid();
674 	    if (ioctl(pbm->filemon_fd, FILEMON_SET_PID, &pid) < 0) {
675 		err(1, "Could not set filemon pid!");
676 	    }
677 	}
678     }
679 #endif
680 }
681 
682 void
683 meta_job_error(Job *job, GNode *gn, int flags, int status)
684 {
685     char cwd[MAXPATHLEN];
686     BuildMon *pbm;
687 
688     if (job != NULL) {
689 	pbm = &job->bm;
690     } else {
691 	if (!gn)
692 	    gn = job->node;
693 	pbm = &Mybm;
694     }
695     if (pbm->mfp != NULL) {
696 	fprintf(pbm->mfp, "*** Error code %d%s\n",
697 		status,
698 		(flags & JOB_IGNERR) ?
699 		"(ignored)" : "");
700     }
701     if (gn) {
702 	Var_Set(".ERROR_TARGET", gn->path ? gn->path : gn->name, VAR_GLOBAL, 0);
703     }
704     getcwd(cwd, sizeof(cwd));
705     Var_Set(".ERROR_CWD", cwd, VAR_GLOBAL, 0);
706     if (pbm && pbm->meta_fname[0]) {
707 	Var_Set(".ERROR_META_FILE", pbm->meta_fname, VAR_GLOBAL, 0);
708     }
709     meta_job_finish(job);
710 }
711 
712 void
713 meta_job_output(Job *job, char *cp, const char *nl)
714 {
715     BuildMon *pbm;
716 
717     if (job != NULL) {
718 	pbm = &job->bm;
719     } else {
720 	pbm = &Mybm;
721     }
722     if (pbm->mfp != NULL) {
723 	if (metaVerbose) {
724 	    static char *meta_prefix = NULL;
725 	    static int meta_prefix_len;
726 
727 	    if (!meta_prefix) {
728 		char *cp2;
729 
730 		meta_prefix = Var_Subst(NULL, "${" MAKE_META_PREFIX "}", VAR_GLOBAL, 0);
731 		if ((cp2 = strchr(meta_prefix, '$')))
732 		    meta_prefix_len = cp2 - meta_prefix;
733 		else
734 		    meta_prefix_len = strlen(meta_prefix);
735 	    }
736 	    if (strncmp(cp, meta_prefix, meta_prefix_len) == 0) {
737 		cp = strchr(cp+1, '\n');
738 		if (!cp++)
739 		    return;
740 	    }
741 	}
742 	fprintf(pbm->mfp, "%s%s", cp, nl);
743     }
744 }
745 
746 void
747 meta_cmd_finish(void *pbmp)
748 {
749 #ifdef USE_FILEMON
750     BuildMon *pbm = pbmp;
751 
752     if (!pbm)
753 	pbm = &Mybm;
754 
755     if (pbm->filemon_fd >= 0) {
756 	close(pbm->filemon_fd);
757 	filemon_read(pbm->mfp, pbm->mon_fd);
758 	pbm->filemon_fd = pbm->mon_fd = -1;
759     }
760 #endif
761 }
762 
763 void
764 meta_job_finish(Job *job)
765 {
766     BuildMon *pbm;
767 
768     if (job != NULL) {
769 	pbm = &job->bm;
770     } else {
771 	pbm = &Mybm;
772     }
773     if (pbm->mfp != NULL) {
774 	meta_cmd_finish(pbm);
775 	fclose(pbm->mfp);
776 	pbm->mfp = NULL;
777 	pbm->meta_fname[0] = '\0';
778     }
779 }
780 
781 /*
782  * Fetch a full line from fp - growing bufp if needed
783  * Return length in bufp.
784  */
785 static int
786 fgetLine(char **bufp, size_t *szp, int o, FILE *fp)
787 {
788     char *buf = *bufp;
789     size_t bufsz = *szp;
790     struct stat fs;
791     int x;
792 
793     if (fgets(&buf[o], bufsz - o, fp) != NULL) {
794     check_newline:
795 	x = o + strlen(&buf[o]);
796 	if (buf[x - 1] == '\n')
797 	    return x;
798 	/*
799 	 * We need to grow the buffer.
800 	 * The meta file can give us a clue.
801 	 */
802 	if (fstat(fileno(fp), &fs) == 0) {
803 	    size_t newsz;
804 	    char *p;
805 
806 	    newsz = ROUNDUP((fs.st_size / 2), BUFSIZ);
807 	    if (newsz <= bufsz)
808 		newsz = ROUNDUP(fs.st_size, BUFSIZ);
809 	    if (DEBUG(META))
810 		fprintf(debug_file, "growing buffer %u -> %u\n",
811 			(unsigned)bufsz, (unsigned)newsz);
812 	    p = bmake_realloc(buf, newsz);
813 	    if (p) {
814 		*bufp = buf = p;
815 		*szp = bufsz = newsz;
816 		/* fetch the rest */
817 		if (!fgets(&buf[x], bufsz - x, fp))
818 		    return x;		/* truncated! */
819 		goto check_newline;
820 	    }
821 	}
822     }
823     return 0;
824 }
825 
826 static int
827 prefix_match(void *p, void *q)
828 {
829     const char *prefix = p;
830     const char *path = q;
831     size_t n = strlen(prefix);
832 
833     return (0 == strncmp(path, prefix, n));
834 }
835 
836 static int
837 string_match(const void *p, const void *q)
838 {
839     const char *p1 = p;
840     const char *p2 = q;
841 
842     return strcmp(p1, p2);
843 }
844 
845 
846 /*
847  * When running with 'meta' functionality, a target can be out-of-date
848  * if any of the references in its meta data file is more recent.
849  * We have to track the latestdir on a per-process basis.
850  */
851 #define LCWD_VNAME_FMT ".meta.%d.lcwd"
852 #define LDIR_VNAME_FMT ".meta.%d.ldir"
853 
854 /*
855  * It is possible that a .meta file is corrupted,
856  * if we detect this we want to reproduce it.
857  * Setting oodate TRUE will have that effect.
858  */
859 #define CHECK_VALID_META(p) if (!(p && *p)) { \
860     warnx("%s: %d: malformed", fname, lineno); \
861     oodate = TRUE; \
862     continue; \
863     }
864 
865 #define DEQUOTE(p) if (*p == '\'') {	\
866     char *ep; \
867     p++; \
868     if ((ep = strchr(p, '\''))) \
869 	*ep = '\0'; \
870     }
871 
872 Boolean
873 meta_oodate(GNode *gn, Boolean oodate)
874 {
875     static char *tmpdir = NULL;
876     static char cwd[MAXPATHLEN];
877     char lcwd_vname[64];
878     char ldir_vname[64];
879     char lcwd[MAXPATHLEN];
880     char latestdir[MAXPATHLEN];
881     char fname[MAXPATHLEN];
882     char fname1[MAXPATHLEN];
883     char fname2[MAXPATHLEN];
884     char fname3[MAXPATHLEN];
885     char *p;
886     char *cp;
887     char *link_src;
888     char *move_target;
889     static size_t cwdlen = 0;
890     static size_t tmplen = 0;
891     FILE *fp;
892     Boolean needOODATE = FALSE;
893     Lst missingFiles;
894 
895     if (oodate)
896 	return oodate;		/* we're done */
897 
898     missingFiles = Lst_Init(FALSE);
899 
900     /*
901      * We need to check if the target is out-of-date. This includes
902      * checking if the expanded command has changed. This in turn
903      * requires that all variables are set in the same way that they
904      * would be if the target needs to be re-built.
905      */
906     Make_DoAllVar(gn);
907 
908     meta_name(gn, fname, sizeof(fname), NULL, NULL);
909 
910 #ifdef DEBUG_META_MODE
911     if (DEBUG(META))
912 	fprintf(debug_file, "meta_oodate: %s\n", fname);
913 #endif
914 
915     if ((fp = fopen(fname, "r")) != NULL) {
916 	static char *buf = NULL;
917 	static size_t bufsz;
918 	int lineno = 0;
919 	int lastpid = 0;
920 	int pid;
921 	int f = 0;
922 	int x;
923 	LstNode ln;
924 	struct stat fs;
925 
926 	if (!buf) {
927 	    bufsz = 8 * BUFSIZ;
928 	    buf = bmake_malloc(bufsz);
929 	}
930 
931 	if (!cwdlen) {
932 	    if (getcwd(cwd, sizeof(cwd)) == NULL)
933 		err(1, "Could not get current working directory");
934 	    cwdlen = strlen(cwd);
935 	}
936 	strlcpy(lcwd, cwd, sizeof(lcwd));
937 	strlcpy(latestdir, cwd, sizeof(latestdir));
938 
939 	if (!tmpdir) {
940 	    tmpdir = getTmpdir();
941 	    tmplen = strlen(tmpdir);
942 	}
943 
944 	/* we want to track all the .meta we read */
945 	Var_Append(".MAKE.META.FILES", fname, VAR_GLOBAL);
946 
947 	ln = Lst_First(gn->commands);
948 	while (!oodate && (x = fgetLine(&buf, &bufsz, 0, fp)) > 0) {
949 	    lineno++;
950 	    if (buf[x - 1] == '\n')
951 		buf[x - 1] = '\0';
952 	    else {
953 		warnx("%s: %d: line truncated at %u", fname, lineno, x);
954 		oodate = TRUE;
955 		break;
956 	    }
957 	    link_src = NULL;
958 	    move_target = NULL;
959 	    /* Find the start of the build monitor section. */
960 	    if (!f) {
961 		if (strncmp(buf, "-- filemon", 10) == 0) {
962 		    f = 1;
963 		    continue;
964 		}
965 		if (strncmp(buf, "# buildmon", 10) == 0) {
966 		    f = 1;
967 		    continue;
968 		}
969 	    }
970 
971 	    /* Delimit the record type. */
972 	    p = buf;
973 #ifdef DEBUG_META_MODE
974 	    if (DEBUG(META))
975 		fprintf(debug_file, "%s: %d: %s\n", fname, lineno, buf);
976 #endif
977 	    strsep(&p, " ");
978 	    if (f) {
979 		/*
980 		 * We are in the 'filemon' output section.
981 		 * Each record from filemon follows the general form:
982 		 *
983 		 * <key> <pid> <data>
984 		 *
985 		 * Where:
986 		 * <key> is a single letter, denoting the syscall.
987 		 * <pid> is the process that made the syscall.
988 		 * <data> is the arguments (of interest).
989 		 */
990 		switch(buf[0]) {
991 		case '#':		/* comment */
992 		case 'V':		/* version */
993 		    break;
994 		default:
995 		    /*
996 		     * We need to track pathnames per-process.
997 		     *
998 		     * Each process run by make, starts off in the 'CWD'
999 		     * recorded in the .meta file, if it chdirs ('C')
1000 		     * elsewhere we need to track that - but only for
1001 		     * that process.  If it forks ('F'), we initialize
1002 		     * the child to have the same cwd as its parent.
1003 		     *
1004 		     * We also need to track the 'latestdir' of
1005 		     * interest.  This is usually the same as cwd, but
1006 		     * not if a process is reading directories.
1007 		     *
1008 		     * Each time we spot a different process ('pid')
1009 		     * we save the current value of 'latestdir' in a
1010 		     * variable qualified by 'lastpid', and
1011 		     * re-initialize 'latestdir' to any pre-saved
1012 		     * value for the current 'pid' and 'CWD' if none.
1013 		     */
1014 		    CHECK_VALID_META(p);
1015 		    pid = atoi(p);
1016 		    if (pid > 0 && pid != lastpid) {
1017 			char *ldir;
1018 			char *tp;
1019 
1020 			if (lastpid > 0) {
1021 			    /* We need to remember these. */
1022 			    Var_Set(lcwd_vname, lcwd, VAR_GLOBAL, 0);
1023 			    Var_Set(ldir_vname, latestdir, VAR_GLOBAL, 0);
1024 			}
1025 			snprintf(lcwd_vname, sizeof(lcwd_vname), LCWD_VNAME_FMT, pid);
1026 			snprintf(ldir_vname, sizeof(ldir_vname), LDIR_VNAME_FMT, pid);
1027 			lastpid = pid;
1028 			ldir = Var_Value(ldir_vname, VAR_GLOBAL, &tp);
1029 			if (ldir) {
1030 			    strlcpy(latestdir, ldir, sizeof(latestdir));
1031 			    if (tp)
1032 				free(tp);
1033 			}
1034 			ldir = Var_Value(lcwd_vname, VAR_GLOBAL, &tp);
1035 			if (ldir) {
1036 			    strlcpy(lcwd, ldir, sizeof(lcwd));
1037 			    if (tp)
1038 				free(tp);
1039 			}
1040 		    }
1041 		    /* Skip past the pid. */
1042 		    if (strsep(&p, " ") == NULL)
1043 			continue;
1044 #ifdef DEBUG_META_MODE
1045 		    if (DEBUG(META))
1046 			    fprintf(debug_file, "%s: %d: %d: %c: cwd=%s lcwd=%s ldir=%s\n",
1047 				    fname, lineno,
1048 				    pid, buf[0], cwd, lcwd, latestdir);
1049 #endif
1050 		    break;
1051 		}
1052 
1053 		CHECK_VALID_META(p);
1054 
1055 		/* Process according to record type. */
1056 		switch (buf[0]) {
1057 		case 'X':		/* eXit */
1058 		    Var_Delete(lcwd_vname, VAR_GLOBAL);
1059 		    Var_Delete(ldir_vname, VAR_GLOBAL);
1060 		    lastpid = 0;	/* no need to save ldir_vname */
1061 		    break;
1062 
1063 		case 'F':		/* [v]Fork */
1064 		    {
1065 			char cldir[64];
1066 			int child;
1067 
1068 			child = atoi(p);
1069 			if (child > 0) {
1070 			    snprintf(cldir, sizeof(cldir), LCWD_VNAME_FMT, child);
1071 			    Var_Set(cldir, lcwd, VAR_GLOBAL, 0);
1072 			    snprintf(cldir, sizeof(cldir), LDIR_VNAME_FMT, child);
1073 			    Var_Set(cldir, latestdir, VAR_GLOBAL, 0);
1074 #ifdef DEBUG_META_MODE
1075 			    if (DEBUG(META))
1076 				    fprintf(debug_file, "%s: %d: %d: cwd=%s lcwd=%s ldir=%s\n",
1077 					    fname, lineno,
1078 					    child, cwd, lcwd, latestdir);
1079 #endif
1080 			}
1081 		    }
1082 		    break;
1083 
1084 		case 'C':		/* Chdir */
1085 		    /* Update lcwd and latest directory. */
1086 		    strlcpy(latestdir, p, sizeof(latestdir));
1087 		    strlcpy(lcwd, p, sizeof(lcwd));
1088 		    Var_Set(lcwd_vname, lcwd, VAR_GLOBAL, 0);
1089 		    Var_Set(ldir_vname, lcwd, VAR_GLOBAL, 0);
1090 #ifdef DEBUG_META_MODE
1091 		    if (DEBUG(META))
1092 			fprintf(debug_file, "%s: %d: cwd=%s ldir=%s\n", fname, lineno, cwd, lcwd);
1093 #endif
1094 		    break;
1095 
1096 		case 'M':		/* renaMe */
1097 		    /*
1098 		     * For 'M'oves we want to check
1099 		     * the src as for 'R'ead
1100 		     * and the target as for 'W'rite.
1101 		     */
1102 		    cp = p;		/* save this for a second */
1103 		    /* now get target */
1104 		    if (strsep(&p, " ") == NULL)
1105 			continue;
1106 		    CHECK_VALID_META(p);
1107 		    move_target = p;
1108 		    p = cp;
1109 		    /* 'L' and 'M' put single quotes around the args */
1110 		    DEQUOTE(p);
1111 		    DEQUOTE(move_target);
1112 		    /* FALLTHROUGH */
1113 		case 'D':		/* unlink */
1114 		    if (*p == '/' && !Lst_IsEmpty(missingFiles)) {
1115 			/* remove p from the missingFiles list if present */
1116 			if ((ln = Lst_Find(missingFiles, p, string_match)) != NULL) {
1117 			    char *tp = Lst_Datum(ln);
1118 			    Lst_Remove(missingFiles, ln);
1119 			    free(tp);
1120 			    ln = NULL;	/* we're done with it */
1121 			}
1122 		    }
1123 		    if (buf[0] == 'M') {
1124 			/* the target of the mv is a file 'W'ritten */
1125 #ifdef DEBUG_META_MODE
1126 			if (DEBUG(META))
1127 			    fprintf(debug_file, "meta_oodate: M %s -> %s\n",
1128 				    p, move_target);
1129 #endif
1130 			p = move_target;
1131 			goto check_write;
1132 		    }
1133 		    break;
1134 		case 'L':		/* Link */
1135 		    /*
1136 		     * For 'L'inks check
1137 		     * the src as for 'R'ead
1138 		     * and the target as for 'W'rite.
1139 		     */
1140 		    link_src = p;
1141 		    /* now get target */
1142 		    if (strsep(&p, " ") == NULL)
1143 			continue;
1144 		    CHECK_VALID_META(p);
1145 		    /* 'L' and 'M' put single quotes around the args */
1146 		    DEQUOTE(p);
1147 		    DEQUOTE(link_src);
1148 #ifdef DEBUG_META_MODE
1149 		    if (DEBUG(META))
1150 			fprintf(debug_file, "meta_oodate: L %s -> %s\n",
1151 				link_src, p);
1152 #endif
1153 		    /* FALLTHROUGH */
1154 		case 'W':		/* Write */
1155 		check_write:
1156 		    /*
1157 		     * If a file we generated within our bailiwick
1158 		     * but outside of .OBJDIR is missing,
1159 		     * we need to do it again.
1160 		     */
1161 		    /* ignore non-absolute paths */
1162 		    if (*p != '/')
1163 			break;
1164 
1165 		    if (Lst_IsEmpty(metaBailiwick))
1166 			break;
1167 
1168 		    /* ignore cwd - normal dependencies handle those */
1169 		    if (strncmp(p, cwd, cwdlen) == 0)
1170 			break;
1171 
1172 		    if (!Lst_ForEach(metaBailiwick, prefix_match, p))
1173 			break;
1174 
1175 		    /* tmpdir might be within */
1176 		    if (tmplen > 0 && strncmp(p, tmpdir, tmplen) == 0)
1177 			break;
1178 
1179 		    /* ignore anything containing the string "tmp" */
1180 		    if ((strstr("tmp", p)))
1181 			break;
1182 
1183 		    if (stat(p, &fs) < 0) {
1184 			Lst_AtEnd(missingFiles, bmake_strdup(p));
1185 		    }
1186 		    break;
1187 		check_link_src:
1188 		    p = link_src;
1189 		    link_src = NULL;
1190 #ifdef DEBUG_META_MODE
1191 		    if (DEBUG(META))
1192 			fprintf(debug_file, "meta_oodate: L src %s\n", p);
1193 #endif
1194 		    /* FALLTHROUGH */
1195 		case 'R':		/* Read */
1196 		case 'E':		/* Exec */
1197 		    /*
1198 		     * Check for runtime files that can't
1199 		     * be part of the dependencies because
1200 		     * they are _expected_ to change.
1201 		     */
1202 		    if (*p == '/' &&
1203 			Lst_ForEach(metaIgnorePaths, prefix_match, p)) {
1204 #ifdef DEBUG_META_MODE
1205 			if (DEBUG(META))
1206 			    fprintf(debug_file, "meta_oodate: ignoring: %s\n",
1207 				    p);
1208 #endif
1209 			break;
1210 		    }
1211 
1212 		    if ((cp = strrchr(p, '/'))) {
1213 			cp++;
1214 			/*
1215 			 * We don't normally expect to see this,
1216 			 * but we do expect it to change.
1217 			 */
1218 			if (strcmp(cp, makeDependfile) == 0)
1219 			    break;
1220 		    }
1221 
1222 		    /*
1223 		     * The rest of the record is the file name.
1224 		     * Check if it's not an absolute path.
1225 		     */
1226 		    {
1227 			char *sdirs[4];
1228 			char **sdp;
1229 			int sdx = 0;
1230 			int found = 0;
1231 
1232 			if (*p == '/') {
1233 			    sdirs[sdx++] = p; /* done */
1234 			} else {
1235 			    if (strcmp(".", p) == 0)
1236 				continue;  /* no point */
1237 
1238 			    /* Check vs latestdir */
1239 			    snprintf(fname1, sizeof(fname1), "%s/%s", latestdir, p);
1240 			    sdirs[sdx++] = fname1;
1241 
1242 			    if (strcmp(latestdir, lcwd) != 0) {
1243 				/* Check vs lcwd */
1244 				snprintf(fname2, sizeof(fname2), "%s/%s", lcwd, p);
1245 				sdirs[sdx++] = fname2;
1246 			    }
1247 			    if (strcmp(lcwd, cwd) != 0) {
1248 				/* Check vs cwd */
1249 				snprintf(fname3, sizeof(fname3), "%s/%s", cwd, p);
1250 				sdirs[sdx++] = fname3;
1251 			    }
1252 			}
1253 			sdirs[sdx++] = NULL;
1254 
1255 			for (sdp = sdirs; *sdp && !found; sdp++) {
1256 #ifdef DEBUG_META_MODE
1257 			    if (DEBUG(META))
1258 				fprintf(debug_file, "%s: %d: looking for: %s\n", fname, lineno, *sdp);
1259 #endif
1260 			    if (stat(*sdp, &fs) == 0) {
1261 				found = 1;
1262 				p = *sdp;
1263 			    }
1264 			}
1265 			if (found) {
1266 #ifdef DEBUG_META_MODE
1267 			    if (DEBUG(META))
1268 				fprintf(debug_file, "%s: %d: found: %s\n", fname, lineno, p);
1269 #endif
1270 			    if (!S_ISDIR(fs.st_mode) &&
1271 				fs.st_mtime > gn->mtime) {
1272 				if (DEBUG(META))
1273 				    fprintf(debug_file, "%s: %d: file '%s' is newer than the target...\n", fname, lineno, p);
1274 				oodate = TRUE;
1275 			    } else if (S_ISDIR(fs.st_mode)) {
1276 				/* Update the latest directory. */
1277 				realpath(p, latestdir);
1278 			    }
1279 			} else if (errno == ENOENT && *p == '/' &&
1280 				   strncmp(p, cwd, cwdlen) != 0) {
1281 			    /*
1282 			     * A referenced file outside of CWD is missing.
1283 			     * We cannot catch every eventuality here...
1284 			     */
1285 			    if (DEBUG(META))
1286 				fprintf(debug_file, "%s: %d: file '%s' may have moved?...\n", fname, lineno, p);
1287 			    oodate = TRUE;
1288 			}
1289 		    }
1290 		    if (buf[0] == 'E') {
1291 			/* previous latestdir is no longer relevant */
1292 			strlcpy(latestdir, lcwd, sizeof(latestdir));
1293 		    }
1294 		    break;
1295 		default:
1296 		    break;
1297 		}
1298 		if (!oodate && buf[0] == 'L' && link_src != NULL)
1299 		    goto check_link_src;
1300 	    } else if (strcmp(buf, "CMD") == 0) {
1301 		/*
1302 		 * Compare the current command with the one in the
1303 		 * meta data file.
1304 		 */
1305 		if (ln == NULL) {
1306 		    if (DEBUG(META))
1307 			fprintf(debug_file, "%s: %d: there were more build commands in the meta data file than there are now...\n", fname, lineno);
1308 		    oodate = TRUE;
1309 		} else {
1310 		    char *cmd = (char *)Lst_Datum(ln);
1311 		    Boolean hasOODATE = FALSE;
1312 
1313 		    if (strstr(cmd, "$?"))
1314 			hasOODATE = TRUE;
1315 		    else if ((cp = strstr(cmd, ".OODATE"))) {
1316 			/* check for $[{(].OODATE[:)}] */
1317 			if (cp > cmd + 2 && cp[-2] == '$')
1318 			    hasOODATE = TRUE;
1319 		    }
1320 		    if (hasOODATE) {
1321 			needOODATE = TRUE;
1322 			if (DEBUG(META))
1323 			    fprintf(debug_file, "%s: %d: cannot compare command using .OODATE\n", fname, lineno);
1324 		    }
1325 		    cmd = Var_Subst(NULL, cmd, gn, TRUE);
1326 
1327 		    if ((cp = strchr(cmd, '\n'))) {
1328 			int n;
1329 
1330 			/*
1331 			 * This command contains newlines, we need to
1332 			 * fetch more from the .meta file before we
1333 			 * attempt a comparison.
1334 			 */
1335 			/* first put the newline back at buf[x - 1] */
1336 			buf[x - 1] = '\n';
1337 			do {
1338 			    /* now fetch the next line */
1339 			    if ((n = fgetLine(&buf, &bufsz, x, fp)) <= 0)
1340 				break;
1341 			    x = n;
1342 			    lineno++;
1343 			    if (buf[x - 1] != '\n') {
1344 				warnx("%s: %d: line truncated at %u", fname, lineno, x);
1345 				break;
1346 			    }
1347 			    cp = strchr(++cp, '\n');
1348 			} while (cp);
1349 			if (buf[x - 1] == '\n')
1350 			    buf[x - 1] = '\0';
1351 		    }
1352 		    if (!hasOODATE &&
1353 			!(gn->type & OP_NOMETA_CMP) &&
1354 			strcmp(p, cmd) != 0) {
1355 			if (DEBUG(META))
1356 			    fprintf(debug_file, "%s: %d: a build command has changed\n%s\nvs\n%s\n", fname, lineno, p, cmd);
1357 			if (!metaIgnoreCMDs)
1358 			    oodate = TRUE;
1359 		    }
1360 		    free(cmd);
1361 		    ln = Lst_Succ(ln);
1362 		}
1363 	    } else if (strcmp(buf, "CWD") == 0) {
1364 		/*
1365 		 * Check if there are extra commands now
1366 		 * that weren't in the meta data file.
1367 		 */
1368 		if (!oodate && ln != NULL) {
1369 		    if (DEBUG(META))
1370 			fprintf(debug_file, "%s: %d: there are extra build commands now that weren't in the meta data file\n", fname, lineno);
1371 		    oodate = TRUE;
1372 		}
1373 		if (strcmp(p, cwd) != 0) {
1374 		    if (DEBUG(META))
1375 			fprintf(debug_file, "%s: %d: the current working directory has changed from '%s' to '%s'\n", fname, lineno, p, curdir);
1376 		    oodate = TRUE;
1377 		}
1378 	    }
1379 	}
1380 
1381 	fclose(fp);
1382 	if (!Lst_IsEmpty(missingFiles)) {
1383 	    if (DEBUG(META))
1384 		fprintf(debug_file, "%s: missing files: %s...\n",
1385 			fname, (char *)Lst_Datum(Lst_First(missingFiles)));
1386 	    oodate = TRUE;
1387 	    Lst_Destroy(missingFiles, (FreeProc *)free);
1388 	}
1389     } else {
1390 	if ((gn->type & OP_META)) {
1391 	    if (DEBUG(META))
1392 		fprintf(debug_file, "%s: required but missing\n", fname);
1393 	    oodate = TRUE;
1394 	}
1395     }
1396     if (oodate && needOODATE) {
1397 	/*
1398 	 * Target uses .OODATE which is empty; or we wouldn't be here.
1399 	 * We have decided it is oodate, so .OODATE needs to be set.
1400 	 * All we can sanely do is set it to .ALLSRC.
1401 	 */
1402 	Var_Delete(OODATE, gn);
1403 	Var_Set(OODATE, Var_Value(ALLSRC, gn, &cp), gn, 0);
1404 	if (cp)
1405 	    free(cp);
1406     }
1407     return oodate;
1408 }
1409 
1410 /* support for compat mode */
1411 
1412 static int childPipe[2];
1413 
1414 void
1415 meta_compat_start(void)
1416 {
1417 #ifdef USE_FILEMON_ONCE
1418     /*
1419      * We need to re-open filemon for each cmd.
1420      */
1421     BuildMon *pbm = &Mybm;
1422 
1423     if (pbm->mfp != NULL && useFilemon) {
1424 	filemon_open(pbm);
1425     } else {
1426 	pbm->mon_fd = pbm->filemon_fd = -1;
1427     }
1428 #endif
1429     if (pipe(childPipe) < 0)
1430 	Punt("Cannot create pipe: %s", strerror(errno));
1431     /* Set close-on-exec flag for both */
1432     (void)fcntl(childPipe[0], F_SETFD, 1);
1433     (void)fcntl(childPipe[1], F_SETFD, 1);
1434 }
1435 
1436 void
1437 meta_compat_child(void)
1438 {
1439     meta_job_child(NULL);
1440     if (dup2(childPipe[1], 1) < 0 ||
1441 	dup2(1, 2) < 0) {
1442 	execError("dup2", "pipe");
1443 	_exit(1);
1444     }
1445 }
1446 
1447 void
1448 meta_compat_parent(void)
1449 {
1450     FILE *fp;
1451     char buf[BUFSIZ];
1452 
1453     close(childPipe[1]);			/* child side */
1454     fp = fdopen(childPipe[0], "r");
1455     while (fgets(buf, sizeof(buf), fp)) {
1456 	meta_job_output(NULL, buf, "");
1457 	printf("%s", buf);
1458     }
1459     fclose(fp);
1460 }
1461 
1462 #endif	/* USE_META */
1463