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meta.c revision 1.183
      1 /*      $NetBSD: meta.c,v 1.183 2021/08/19 15:50:30 rillig Exp $ */
      2 
      3 /*
      4  * Implement 'meta' mode.
      5  * Adapted from John Birrell's patches to FreeBSD make.
      6  * --sjg
      7  */
      8 /*
      9  * Copyright (c) 2009-2016, 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 <libgen.h>
     40 #include <errno.h>
     41 #if !defined(HAVE_CONFIG_H) || defined(HAVE_ERR_H)
     42 #include <err.h>
     43 #endif
     44 
     45 #include "make.h"
     46 #include "dir.h"
     47 #include "job.h"
     48 
     49 #ifdef USE_FILEMON
     50 #include "filemon/filemon.h"
     51 #endif
     52 
     53 static BuildMon Mybm;			/* for compat */
     54 static StringList metaBailiwick = LST_INIT; /* our scope of control */
     55 static char *metaBailiwickStr;		/* string storage for the list */
     56 static StringList metaIgnorePaths = LST_INIT; /* paths we deliberately ignore */
     57 static char *metaIgnorePathsStr;	/* string storage for the list */
     58 
     59 #ifndef MAKE_META_IGNORE_PATHS
     60 #define MAKE_META_IGNORE_PATHS ".MAKE.META.IGNORE_PATHS"
     61 #endif
     62 #ifndef MAKE_META_IGNORE_PATTERNS
     63 #define MAKE_META_IGNORE_PATTERNS ".MAKE.META.IGNORE_PATTERNS"
     64 #endif
     65 #ifndef MAKE_META_IGNORE_FILTER
     66 #define MAKE_META_IGNORE_FILTER ".MAKE.META.IGNORE_FILTER"
     67 #endif
     68 
     69 bool useMeta = false;
     70 static bool useFilemon = false;
     71 static bool writeMeta = false;
     72 static bool metaMissing = false;	/* oodate if missing */
     73 static bool filemonMissing = false;	/* oodate if missing */
     74 static bool metaEnv = false;		/* don't save env unless asked */
     75 static bool metaVerbose = false;
     76 static bool metaIgnoreCMDs = false;	/* ignore CMDs in .meta files */
     77 static bool metaIgnorePatterns = false; /* do we need to do pattern matches */
     78 static bool metaIgnoreFilter = false;	/* do we have more complex filtering? */
     79 static bool metaCurdirOk = false;	/* write .meta in .CURDIR Ok? */
     80 static bool metaSilent = false;		/* if we have a .meta be SILENT */
     81 
     82 extern bool forceJobs;
     83 extern char    **environ;
     84 
     85 #define MAKE_META_PREFIX	".MAKE.META.PREFIX"
     86 
     87 #ifndef N2U
     88 # define N2U(n, u)   (((n) + ((u) - 1)) / (u))
     89 #endif
     90 #ifndef ROUNDUP
     91 # define ROUNDUP(n, u)   (N2U((n), (u)) * (u))
     92 #endif
     93 
     94 #if !defined(HAVE_STRSEP)
     95 # define strsep(s, d) stresep((s), (d), '\0')
     96 #endif
     97 
     98 /*
     99  * Filemon is a kernel module which snoops certain syscalls.
    100  *
    101  * C chdir
    102  * E exec
    103  * F [v]fork
    104  * L [sym]link
    105  * M rename
    106  * R read
    107  * W write
    108  * S stat
    109  *
    110  * See meta_oodate below - we mainly care about 'E' and 'R'.
    111  *
    112  * We can still use meta mode without filemon, but
    113  * the benefits are more limited.
    114  */
    115 #ifdef USE_FILEMON
    116 
    117 /*
    118  * Open the filemon device.
    119  */
    120 static void
    121 meta_open_filemon(BuildMon *pbm)
    122 {
    123     int dupfd;
    124 
    125     pbm->mon_fd = -1;
    126     pbm->filemon = NULL;
    127     if (!useFilemon || pbm->mfp == NULL)
    128 	return;
    129 
    130     pbm->filemon = filemon_open();
    131     if (pbm->filemon == NULL) {
    132 	useFilemon = false;
    133 	warn("Could not open filemon %s", filemon_path());
    134 	return;
    135     }
    136 
    137     /*
    138      * We use a file outside of '.'
    139      * to avoid a FreeBSD kernel bug where unlink invalidates
    140      * cwd causing getcwd to do a lot more work.
    141      * We only care about the descriptor.
    142      */
    143     if (!opts.compatMake)
    144 	pbm->mon_fd = Job_TempFile("filemon.XXXXXX", NULL, 0);
    145     else
    146 	pbm->mon_fd = mkTempFile("filemon.XXXXXX", NULL, 0);
    147     if ((dupfd = dup(pbm->mon_fd)) == -1) {
    148 	err(1, "Could not dup filemon output!");
    149     }
    150     (void)fcntl(dupfd, F_SETFD, FD_CLOEXEC);
    151     if (filemon_setfd(pbm->filemon, dupfd) == -1) {
    152 	err(1, "Could not set filemon file descriptor!");
    153     }
    154     /* we don't need these once we exec */
    155     (void)fcntl(pbm->mon_fd, F_SETFD, FD_CLOEXEC);
    156 }
    157 
    158 /*
    159  * Read the build monitor output file and write records to the target's
    160  * metadata file.
    161  */
    162 static int
    163 filemon_read(FILE *mfp, int fd)
    164 {
    165     char buf[BUFSIZ];
    166     int error;
    167 
    168     /* Check if we're not writing to a meta data file.*/
    169     if (mfp == NULL) {
    170 	if (fd >= 0)
    171 	    close(fd);			/* not interested */
    172 	return 0;
    173     }
    174     /* rewind */
    175     if (lseek(fd, (off_t)0, SEEK_SET) < 0) {
    176 	error = errno;
    177 	warn("Could not rewind filemon");
    178 	fprintf(mfp, "\n");
    179     } else {
    180 	ssize_t n;
    181 
    182 	error = 0;
    183 	fprintf(mfp, "\n-- filemon acquired metadata --\n");
    184 
    185 	while ((n = read(fd, buf, sizeof buf)) > 0) {
    186 	    if ((ssize_t)fwrite(buf, 1, (size_t)n, mfp) < n)
    187 		error = EIO;
    188 	}
    189     }
    190     fflush(mfp);
    191     if (close(fd) < 0)
    192 	error = errno;
    193     return error;
    194 }
    195 #endif
    196 
    197 /*
    198  * when realpath() fails,
    199  * we use this, to clean up ./ and ../
    200  */
    201 static void
    202 eat_dots(char *buf, size_t bufsz, int dots)
    203 {
    204     char *cp;
    205     char *cp2;
    206     const char *eat;
    207     size_t eatlen;
    208 
    209     switch (dots) {
    210     case 1:
    211 	eat = "/./";
    212 	eatlen = 2;
    213 	break;
    214     case 2:
    215 	eat = "/../";
    216 	eatlen = 3;
    217 	break;
    218     default:
    219 	return;
    220     }
    221 
    222     do {
    223 	cp = strstr(buf, eat);
    224 	if (cp != NULL) {
    225 	    cp2 = cp + eatlen;
    226 	    if (dots == 2 && cp > buf) {
    227 		do {
    228 		    cp--;
    229 		} while (cp > buf && *cp != '/');
    230 	    }
    231 	    if (*cp == '/') {
    232 		strlcpy(cp, cp2, bufsz - (size_t)(cp - buf));
    233 	    } else {
    234 		return;			/* can't happen? */
    235 	    }
    236 	}
    237     } while (cp != NULL);
    238 }
    239 
    240 static char *
    241 meta_name(char *mname, size_t mnamelen,
    242 	  const char *dname,
    243 	  const char *tname,
    244 	  const char *cwd)
    245 {
    246     char buf[MAXPATHLEN];
    247     char *rp, *cp;
    248     const char *tname_base;
    249     char *tp;
    250     char *dtp;
    251     size_t ldname;
    252 
    253     /*
    254      * Weed out relative paths from the target file name.
    255      * We have to be careful though since if target is a
    256      * symlink, the result will be unstable.
    257      * So we use realpath() just to get the dirname, and leave the
    258      * basename as given to us.
    259      */
    260     if ((tname_base = strrchr(tname, '/')) != NULL) {
    261 	if (cached_realpath(tname, buf) != NULL) {
    262 	    if ((rp = strrchr(buf, '/')) != NULL) {
    263 		rp++;
    264 		tname_base++;
    265 		if (strcmp(tname_base, rp) != 0)
    266 		    strlcpy(rp, tname_base, sizeof buf - (size_t)(rp - buf));
    267 	    }
    268 	    tname = buf;
    269 	} else {
    270 	    /*
    271 	     * We likely have a directory which is about to be made.
    272 	     * We pretend realpath() succeeded, to have a chance
    273 	     * of generating the same meta file name that we will
    274 	     * next time through.
    275 	     */
    276 	    if (tname[0] == '/') {
    277 		strlcpy(buf, tname, sizeof buf);
    278 	    } else {
    279 		snprintf(buf, sizeof buf, "%s/%s", cwd, tname);
    280 	    }
    281 	    eat_dots(buf, sizeof buf, 1);	/* ./ */
    282 	    eat_dots(buf, sizeof buf, 2);	/* ../ */
    283 	    tname = buf;
    284 	}
    285     }
    286     /* on some systems dirname may modify its arg */
    287     tp = bmake_strdup(tname);
    288     dtp = dirname(tp);
    289     if (strcmp(dname, dtp) == 0)
    290 	snprintf(mname, mnamelen, "%s.meta", tname);
    291     else {
    292 	ldname = strlen(dname);
    293 	if (strncmp(dname, dtp, ldname) == 0 && dtp[ldname] == '/')
    294 	    snprintf(mname, mnamelen, "%s/%s.meta", dname, &tname[ldname+1]);
    295 	else
    296 	    snprintf(mname, mnamelen, "%s/%s.meta", dname, tname);
    297 
    298 	/*
    299 	 * Replace path separators in the file name after the
    300 	 * current object directory path.
    301 	 */
    302 	cp = mname + strlen(dname) + 1;
    303 
    304 	while (*cp != '\0') {
    305 	    if (*cp == '/')
    306 		*cp = '_';
    307 	    cp++;
    308 	}
    309     }
    310     free(tp);
    311     return mname;
    312 }
    313 
    314 /*
    315  * Return true if running ${.MAKE}
    316  * Bypassed if target is flagged .MAKE
    317  */
    318 static bool
    319 is_submake(const char *cmd, GNode *gn)
    320 {
    321     static const char *p_make = NULL;
    322     static size_t p_len;
    323     char *mp = NULL;
    324     const char *cp, *cp2;
    325     bool rc = false;
    326 
    327     if (p_make == NULL) {
    328 	p_make = Var_Value(gn, ".MAKE").str;
    329 	p_len = strlen(p_make);
    330     }
    331     cp = strchr(cmd, '$');
    332     if (cp != NULL) {
    333 	(void)Var_Subst(cmd, gn, VARE_WANTRES, &mp);
    334 	/* TODO: handle errors */
    335 	cmd = mp;
    336     }
    337     cp2 = strstr(cmd, p_make);
    338     if (cp2 != NULL) {
    339 	switch (cp2[p_len]) {
    340 	case '\0':
    341 	case ' ':
    342 	case '\t':
    343 	case '\n':
    344 	    rc = true;
    345 	    break;
    346 	}
    347 	if (cp2 > cmd && rc) {
    348 	    switch (cp2[-1]) {
    349 	    case ' ':
    350 	    case '\t':
    351 	    case '\n':
    352 		break;
    353 	    default:
    354 		rc = false;		/* no match */
    355 		break;
    356 	    }
    357 	}
    358     }
    359     free(mp);
    360     return rc;
    361 }
    362 
    363 static bool
    364 any_is_submake(GNode *gn)
    365 {
    366     StringListNode *ln;
    367 
    368     for (ln = gn->commands.first; ln != NULL; ln = ln->next)
    369 	if (is_submake(ln->datum, gn))
    370 	    return true;
    371     return false;
    372 }
    373 
    374 static void
    375 printCMD(const char *ucmd, FILE *fp, GNode *gn)
    376 {
    377     FStr xcmd = FStr_InitRefer(ucmd);
    378 
    379     if (strchr(ucmd, '$') != NULL) {
    380     	char *expanded;
    381 	(void)Var_Subst(ucmd, gn, VARE_WANTRES, &expanded);
    382 	/* TODO: handle errors */
    383 	xcmd = FStr_InitOwn(expanded);
    384     }
    385 
    386     fprintf(fp, "CMD %s\n", xcmd.str);
    387     FStr_Done(&xcmd);
    388 }
    389 
    390 static void
    391 printCMDs(GNode *gn, FILE *fp)
    392 {
    393     StringListNode *ln;
    394 
    395     for (ln = gn->commands.first; ln != NULL; ln = ln->next)
    396 	printCMD(ln->datum, fp, gn);
    397 }
    398 
    399 /*
    400  * Certain node types never get a .meta file
    401  */
    402 #define SKIP_META_TYPE(_type) do { \
    403     if ((gn->type & __CONCAT(OP_, _type))) { \
    404 	if (verbose) { \
    405 	    debug_printf("Skipping meta for %s: .%s\n", \
    406 		    gn->name, __STRING(_type)); \
    407 	} \
    408 	return false; \
    409     } \
    410 } while (/*CONSTCOND*/false)
    411 
    412 
    413 /*
    414  * Do we need/want a .meta file ?
    415  */
    416 static bool
    417 meta_needed(GNode *gn, const char *dname,
    418 	    char *objdir_realpath, bool verbose)
    419 {
    420     struct cached_stat cst;
    421 
    422     if (verbose)
    423 	verbose = DEBUG(META);
    424 
    425     /* This may be a phony node which we don't want meta data for... */
    426     /* Skip .meta for .BEGIN, .END, .ERROR etc as well. */
    427     /* Or it may be explicitly flagged as .NOMETA */
    428     SKIP_META_TYPE(NOMETA);
    429     /* Unless it is explicitly flagged as .META */
    430     if (!(gn->type & OP_META)) {
    431 	SKIP_META_TYPE(PHONY);
    432 	SKIP_META_TYPE(SPECIAL);
    433 	SKIP_META_TYPE(MAKE);
    434     }
    435 
    436     /* Check if there are no commands to execute. */
    437     if (Lst_IsEmpty(&gn->commands)) {
    438 	if (verbose)
    439 	    debug_printf("Skipping meta for %s: no commands\n", gn->name);
    440 	return false;
    441     }
    442     if ((gn->type & (OP_META|OP_SUBMAKE)) == OP_SUBMAKE) {
    443 	/* OP_SUBMAKE is a bit too aggressive */
    444 	if (any_is_submake(gn)) {
    445 	    DEBUG1(META, "Skipping meta for %s: .SUBMAKE\n", gn->name);
    446 	    return false;
    447 	}
    448     }
    449 
    450     /* The object directory may not exist. Check it.. */
    451     if (cached_stat(dname, &cst) != 0) {
    452 	if (verbose)
    453 	    debug_printf("Skipping meta for %s: no .OBJDIR\n", gn->name);
    454 	return false;
    455     }
    456 
    457     /* make sure these are canonical */
    458     if (cached_realpath(dname, objdir_realpath) != NULL)
    459 	dname = objdir_realpath;
    460 
    461     /* If we aren't in the object directory, don't create a meta file. */
    462     if (!metaCurdirOk && strcmp(curdir, dname) == 0) {
    463 	if (verbose)
    464 	    debug_printf("Skipping meta for %s: .OBJDIR == .CURDIR\n",
    465 			 gn->name);
    466 	return false;
    467     }
    468     return true;
    469 }
    470 
    471 
    472 static FILE *
    473 meta_create(BuildMon *pbm, GNode *gn)
    474 {
    475     FILE *fp;
    476     char buf[MAXPATHLEN];
    477     char objdir_realpath[MAXPATHLEN];
    478     char **ptr;
    479     FStr dname;
    480     const char *tname;
    481     char *fname;
    482     const char *cp;
    483 
    484     fp = NULL;
    485 
    486     dname = Var_Value(gn, ".OBJDIR");
    487     tname = GNode_VarTarget(gn);
    488 
    489     /* if this succeeds objdir_realpath is realpath of dname */
    490     if (!meta_needed(gn, dname.str, objdir_realpath, true))
    491 	goto out;
    492     dname.str = objdir_realpath;
    493 
    494     if (metaVerbose) {
    495 	char *mp;
    496 
    497 	/* Describe the target we are building */
    498 	(void)Var_Subst("${" MAKE_META_PREFIX "}", gn, VARE_WANTRES, &mp);
    499 	/* TODO: handle errors */
    500 	if (mp[0] != '\0')
    501 	    fprintf(stdout, "%s\n", mp);
    502 	free(mp);
    503     }
    504     /* Get the basename of the target */
    505     cp = str_basename(tname);
    506 
    507     fflush(stdout);
    508 
    509     if (!writeMeta)
    510 	/* Don't create meta data. */
    511 	goto out;
    512 
    513     fname = meta_name(pbm->meta_fname, sizeof pbm->meta_fname,
    514 		      dname.str, tname, objdir_realpath);
    515 
    516 #ifdef DEBUG_META_MODE
    517     DEBUG1(META, "meta_create: %s\n", fname);
    518 #endif
    519 
    520     if ((fp = fopen(fname, "w")) == NULL)
    521 	err(1, "Could not open meta file '%s'", fname);
    522 
    523     fprintf(fp, "# Meta data file %s\n", fname);
    524 
    525     printCMDs(gn, fp);
    526 
    527     fprintf(fp, "CWD %s\n", getcwd(buf, sizeof buf));
    528     fprintf(fp, "TARGET %s\n", tname);
    529     cp = GNode_VarOodate(gn);
    530     if (cp != NULL && *cp != '\0') {
    531 	fprintf(fp, "OODATE %s\n", cp);
    532     }
    533     if (metaEnv) {
    534 	for (ptr = environ; *ptr != NULL; ptr++)
    535 	    fprintf(fp, "ENV %s\n", *ptr);
    536     }
    537 
    538     fprintf(fp, "-- command output --\n");
    539     fflush(fp);
    540 
    541     Global_Append(".MAKE.META.FILES", fname);
    542     Global_Append(".MAKE.META.CREATED", fname);
    543 
    544     gn->type |= OP_META;		/* in case anyone wants to know */
    545     if (metaSilent) {
    546 	    gn->type |= OP_SILENT;
    547     }
    548  out:
    549     FStr_Done(&dname);
    550 
    551     return fp;
    552 }
    553 
    554 static bool
    555 boolValue(const char *s)
    556 {
    557     switch (*s) {
    558     case '0':
    559     case 'N':
    560     case 'n':
    561     case 'F':
    562     case 'f':
    563 	return false;
    564     }
    565     return true;
    566 }
    567 
    568 /*
    569  * Initialization we need before reading makefiles.
    570  */
    571 void
    572 meta_init(void)
    573 {
    574 #ifdef USE_FILEMON
    575 	/* this allows makefiles to test if we have filemon support */
    576 	Global_Set(".MAKE.PATH_FILEMON", filemon_path());
    577 #endif
    578 }
    579 
    580 
    581 #define get_mode_bf(bf, token) \
    582     if ((cp = strstr(make_mode, token)) != NULL) \
    583 	bf = boolValue(cp + sizeof (token) - 1)
    584 
    585 /*
    586  * Initialization we need after reading makefiles.
    587  */
    588 void
    589 meta_mode_init(const char *make_mode)
    590 {
    591     static bool once = false;
    592     const char *cp;
    593     FStr value;
    594 
    595     useMeta = true;
    596     useFilemon = true;
    597     writeMeta = true;
    598 
    599     if (make_mode != NULL) {
    600 	if (strstr(make_mode, "env") != NULL)
    601 	    metaEnv = true;
    602 	if (strstr(make_mode, "verb") != NULL)
    603 	    metaVerbose = true;
    604 	if (strstr(make_mode, "read") != NULL)
    605 	    writeMeta = false;
    606 	if (strstr(make_mode, "nofilemon") != NULL)
    607 	    useFilemon = false;
    608 	if (strstr(make_mode, "ignore-cmd") != NULL)
    609 	    metaIgnoreCMDs = true;
    610 	if (useFilemon)
    611 	    get_mode_bf(filemonMissing, "missing-filemon=");
    612 	get_mode_bf(metaCurdirOk, "curdirok=");
    613 	get_mode_bf(metaMissing, "missing-meta=");
    614 	get_mode_bf(metaSilent, "silent=");
    615     }
    616     if (metaVerbose && !Var_Exists(SCOPE_GLOBAL, MAKE_META_PREFIX)) {
    617 	/*
    618 	 * The default value for MAKE_META_PREFIX
    619 	 * prints the absolute path of the target.
    620 	 * This works be cause :H will generate '.' if there is no /
    621 	 * and :tA will resolve that to cwd.
    622 	 */
    623 	Global_Set(MAKE_META_PREFIX,
    624 	    "Building ${.TARGET:H:tA}/${.TARGET:T}");
    625     }
    626     if (once)
    627 	return;
    628     once = true;
    629     memset(&Mybm, 0, sizeof Mybm);
    630     /*
    631      * We consider ourselves master of all within ${.MAKE.META.BAILIWICK}
    632      */
    633     (void)Var_Subst("${.MAKE.META.BAILIWICK:O:u:tA}",
    634 		    SCOPE_GLOBAL, VARE_WANTRES, &metaBailiwickStr);
    635     /* TODO: handle errors */
    636     str2Lst_Append(&metaBailiwick, metaBailiwickStr);
    637     /*
    638      * We ignore any paths that start with ${.MAKE.META.IGNORE_PATHS}
    639      */
    640     Global_Append(MAKE_META_IGNORE_PATHS,
    641 	       "/dev /etc /proc /tmp /var/run /var/tmp ${TMPDIR}");
    642     (void)Var_Subst("${" MAKE_META_IGNORE_PATHS ":O:u:tA}",
    643 		    SCOPE_GLOBAL, VARE_WANTRES, &metaIgnorePathsStr);
    644     /* TODO: handle errors */
    645     str2Lst_Append(&metaIgnorePaths, metaIgnorePathsStr);
    646 
    647     /*
    648      * We ignore any paths that match ${.MAKE.META.IGNORE_PATTERNS}
    649      */
    650     value = Var_Value(SCOPE_GLOBAL, MAKE_META_IGNORE_PATTERNS);
    651     if (value.str != NULL) {
    652 	metaIgnorePatterns = true;
    653 	FStr_Done(&value);
    654     }
    655     value = Var_Value(SCOPE_GLOBAL, MAKE_META_IGNORE_FILTER);
    656     if (value.str != NULL) {
    657 	metaIgnoreFilter = true;
    658 	FStr_Done(&value);
    659     }
    660 }
    661 
    662 /*
    663  * In each case below we allow for job==NULL
    664  */
    665 void
    666 meta_job_start(Job *job, GNode *gn)
    667 {
    668     BuildMon *pbm;
    669 
    670     if (job != NULL) {
    671 	pbm = &job->bm;
    672     } else {
    673 	pbm = &Mybm;
    674     }
    675     pbm->mfp = meta_create(pbm, gn);
    676 #ifdef USE_FILEMON_ONCE
    677     /* compat mode we open the filemon dev once per command */
    678     if (job == NULL)
    679 	return;
    680 #endif
    681 #ifdef USE_FILEMON
    682     if (pbm->mfp != NULL && useFilemon) {
    683 	meta_open_filemon(pbm);
    684     } else {
    685 	pbm->mon_fd = -1;
    686 	pbm->filemon = NULL;
    687     }
    688 #endif
    689 }
    690 
    691 /*
    692  * The child calls this before doing anything.
    693  * It does not disturb our state.
    694  */
    695 void
    696 meta_job_child(Job *job)
    697 {
    698 #ifdef USE_FILEMON
    699     BuildMon *pbm;
    700 
    701     if (job != NULL) {
    702 	pbm = &job->bm;
    703     } else {
    704 	pbm = &Mybm;
    705     }
    706     if (pbm->mfp != NULL) {
    707 	close(fileno(pbm->mfp));
    708 	if (useFilemon && pbm->filemon != NULL) {
    709 	    pid_t pid;
    710 
    711 	    pid = getpid();
    712 	    if (filemon_setpid_child(pbm->filemon, pid) == -1) {
    713 		err(1, "Could not set filemon pid!");
    714 	    }
    715 	}
    716     }
    717 #endif
    718 }
    719 
    720 void
    721 meta_job_parent(Job *job, pid_t pid)
    722 {
    723 #if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
    724     BuildMon *pbm;
    725 
    726     if (job != NULL) {
    727 	pbm = &job->bm;
    728     } else {
    729 	pbm = &Mybm;
    730     }
    731     if (useFilemon && pbm->filemon != NULL) {
    732 	filemon_setpid_parent(pbm->filemon, pid);
    733     }
    734 #endif
    735 }
    736 
    737 int
    738 meta_job_fd(Job *job)
    739 {
    740 #if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
    741     BuildMon *pbm;
    742 
    743     if (job != NULL) {
    744 	pbm = &job->bm;
    745     } else {
    746 	pbm = &Mybm;
    747     }
    748     if (useFilemon && pbm->filemon != NULL) {
    749 	return filemon_readfd(pbm->filemon);
    750     }
    751 #endif
    752     return -1;
    753 }
    754 
    755 int
    756 meta_job_event(Job *job)
    757 {
    758 #if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
    759     BuildMon *pbm;
    760 
    761     if (job != NULL) {
    762 	pbm = &job->bm;
    763     } else {
    764 	pbm = &Mybm;
    765     }
    766     if (useFilemon && pbm->filemon != NULL) {
    767 	return filemon_process(pbm->filemon);
    768     }
    769 #endif
    770     return 0;
    771 }
    772 
    773 void
    774 meta_job_error(Job *job, GNode *gn, bool ignerr, int status)
    775 {
    776     char cwd[MAXPATHLEN];
    777     BuildMon *pbm;
    778 
    779     if (job != NULL) {
    780 	pbm = &job->bm;
    781 	if (gn == NULL)
    782 	    gn = job->node;
    783     } else {
    784 	pbm = &Mybm;
    785     }
    786     if (pbm->mfp != NULL) {
    787 	fprintf(pbm->mfp, "\n*** Error code %d%s\n",
    788 		status, ignerr ? "(ignored)" : "");
    789     }
    790     if (gn != NULL)
    791 	Global_Set(".ERROR_TARGET", GNode_Path(gn));
    792     getcwd(cwd, sizeof cwd);
    793     Global_Set(".ERROR_CWD", cwd);
    794     if (pbm->meta_fname[0] != '\0') {
    795 	Global_Set(".ERROR_META_FILE", pbm->meta_fname);
    796     }
    797     meta_job_finish(job);
    798 }
    799 
    800 void
    801 meta_job_output(Job *job, char *cp, const char *nl)
    802 {
    803     BuildMon *pbm;
    804 
    805     if (job != NULL) {
    806 	pbm = &job->bm;
    807     } else {
    808 	pbm = &Mybm;
    809     }
    810     if (pbm->mfp != NULL) {
    811 	if (metaVerbose) {
    812 	    static char *meta_prefix = NULL;
    813 	    static size_t meta_prefix_len;
    814 
    815 	    if (meta_prefix == NULL) {
    816 		char *cp2;
    817 
    818 		(void)Var_Subst("${" MAKE_META_PREFIX "}",
    819 				SCOPE_GLOBAL, VARE_WANTRES, &meta_prefix);
    820 		/* TODO: handle errors */
    821 		if ((cp2 = strchr(meta_prefix, '$')) != NULL)
    822 		    meta_prefix_len = (size_t)(cp2 - meta_prefix);
    823 		else
    824 		    meta_prefix_len = strlen(meta_prefix);
    825 	    }
    826 	    if (strncmp(cp, meta_prefix, meta_prefix_len) == 0) {
    827 		cp = strchr(cp + 1, '\n');
    828 		if (cp == NULL)
    829 		    return;
    830 		cp++;
    831 	    }
    832 	}
    833 	fprintf(pbm->mfp, "%s%s", cp, nl);
    834     }
    835 }
    836 
    837 int
    838 meta_cmd_finish(void *pbmp)
    839 {
    840     int error = 0;
    841     BuildMon *pbm = pbmp;
    842 #ifdef USE_FILEMON
    843     int x;
    844 #endif
    845 
    846     if (pbm == NULL)
    847 	pbm = &Mybm;
    848 
    849 #ifdef USE_FILEMON
    850     if (pbm->filemon != NULL) {
    851 	while (filemon_process(pbm->filemon) > 0)
    852 	    continue;
    853 	if (filemon_close(pbm->filemon) == -1)
    854 	    error = errno;
    855 	x = filemon_read(pbm->mfp, pbm->mon_fd);
    856 	if (error == 0 && x != 0)
    857 	    error = x;
    858 	pbm->mon_fd = -1;
    859 	pbm->filemon = NULL;
    860 	return error;
    861     }
    862 #endif
    863 
    864     fprintf(pbm->mfp, "\n");	/* ensure end with newline */
    865     return error;
    866 }
    867 
    868 int
    869 meta_job_finish(Job *job)
    870 {
    871     BuildMon *pbm;
    872     int error = 0;
    873     int x;
    874 
    875     if (job != NULL) {
    876 	pbm = &job->bm;
    877     } else {
    878 	pbm = &Mybm;
    879     }
    880     if (pbm->mfp != NULL) {
    881 	error = meta_cmd_finish(pbm);
    882 	x = fclose(pbm->mfp);
    883 	if (error == 0 && x != 0)
    884 	    error = errno;
    885 	pbm->mfp = NULL;
    886 	pbm->meta_fname[0] = '\0';
    887     }
    888     return error;
    889 }
    890 
    891 void
    892 meta_finish(void)
    893 {
    894     Lst_Done(&metaBailiwick);
    895     free(metaBailiwickStr);
    896     Lst_Done(&metaIgnorePaths);
    897     free(metaIgnorePathsStr);
    898 }
    899 
    900 /*
    901  * Fetch a full line from fp - growing bufp if needed
    902  * Return length in bufp.
    903  */
    904 static int
    905 fgetLine(char **bufp, size_t *szp, int o, FILE *fp)
    906 {
    907     char *buf = *bufp;
    908     size_t bufsz = *szp;
    909     struct stat fs;
    910     int x;
    911 
    912     if (fgets(&buf[o], (int)bufsz - o, fp) != NULL) {
    913     check_newline:
    914 	x = o + (int)strlen(&buf[o]);
    915 	if (buf[x - 1] == '\n')
    916 	    return x;
    917 	/*
    918 	 * We need to grow the buffer.
    919 	 * The meta file can give us a clue.
    920 	 */
    921 	if (fstat(fileno(fp), &fs) == 0) {
    922 	    size_t newsz;
    923 	    char *p;
    924 
    925 	    newsz = ROUNDUP(((size_t)fs.st_size / 2), BUFSIZ);
    926 	    if (newsz <= bufsz)
    927 		newsz = ROUNDUP((size_t)fs.st_size, BUFSIZ);
    928 	    if (newsz <= bufsz)
    929 		return x;		/* truncated */
    930 	    DEBUG2(META, "growing buffer %u -> %u\n",
    931 		   (unsigned)bufsz, (unsigned)newsz);
    932 	    p = bmake_realloc(buf, newsz);
    933 	    *bufp = buf = p;
    934 	    *szp = bufsz = newsz;
    935 	    /* fetch the rest */
    936 	    if (fgets(&buf[x], (int)bufsz - x, fp) == NULL)
    937 		return x;		/* truncated! */
    938 	    goto check_newline;
    939 	}
    940     }
    941     return 0;
    942 }
    943 
    944 static bool
    945 prefix_match(const char *prefix, const char *path)
    946 {
    947     size_t n = strlen(prefix);
    948 
    949     return strncmp(path, prefix, n) == 0;
    950 }
    951 
    952 static bool
    953 has_any_prefix(const char *path, StringList *prefixes)
    954 {
    955     StringListNode *ln;
    956 
    957     for (ln = prefixes->first; ln != NULL; ln = ln->next)
    958 	if (prefix_match(ln->datum, path))
    959 	    return true;
    960     return false;
    961 }
    962 
    963 /* See if the path equals prefix or starts with "prefix/". */
    964 static bool
    965 path_starts_with(const char *path, const char *prefix)
    966 {
    967     size_t n = strlen(prefix);
    968 
    969     if (strncmp(path, prefix, n) != 0)
    970 	return false;
    971     return path[n] == '\0' || path[n] == '/';
    972 }
    973 
    974 static bool
    975 meta_ignore(GNode *gn, const char *p)
    976 {
    977     char fname[MAXPATHLEN];
    978 
    979     if (p == NULL)
    980 	return true;
    981 
    982     if (*p == '/') {
    983 	cached_realpath(p, fname); /* clean it up */
    984 	if (has_any_prefix(fname, &metaIgnorePaths)) {
    985 #ifdef DEBUG_META_MODE
    986 	    DEBUG1(META, "meta_oodate: ignoring path: %s\n", p);
    987 #endif
    988 	    return true;
    989 	}
    990     }
    991 
    992     if (metaIgnorePatterns) {
    993 	const char *expr;
    994 	char *pm;
    995 
    996 	/*
    997 	 * XXX: This variable is set on a target GNode but is not one of
    998 	 * the usual local variables.  It should be deleted afterwards.
    999 	 * Ideally it would not be created in the first place, just like
   1000 	 * in a .for loop.
   1001 	 */
   1002 	Var_Set(gn, ".p.", p);
   1003 	expr = "${" MAKE_META_IGNORE_PATTERNS ":@m@${.p.:M$m}@}";
   1004 	(void)Var_Subst(expr, gn, VARE_WANTRES, &pm);
   1005 	/* TODO: handle errors */
   1006 	if (pm[0] != '\0') {
   1007 #ifdef DEBUG_META_MODE
   1008 	    DEBUG1(META, "meta_oodate: ignoring pattern: %s\n", p);
   1009 #endif
   1010 	    free(pm);
   1011 	    return true;
   1012 	}
   1013 	free(pm);
   1014     }
   1015 
   1016     if (metaIgnoreFilter) {
   1017 	char *fm;
   1018 
   1019 	/* skip if filter result is empty */
   1020 	snprintf(fname, sizeof fname,
   1021 		 "${%s:L:${%s:ts:}}",
   1022 		 p, MAKE_META_IGNORE_FILTER);
   1023 	(void)Var_Subst(fname, gn, VARE_WANTRES, &fm);
   1024 	/* TODO: handle errors */
   1025 	if (*fm == '\0') {
   1026 #ifdef DEBUG_META_MODE
   1027 	    DEBUG1(META, "meta_oodate: ignoring filtered: %s\n", p);
   1028 #endif
   1029 	    free(fm);
   1030 	    return true;
   1031 	}
   1032 	free(fm);
   1033     }
   1034     return false;
   1035 }
   1036 
   1037 /*
   1038  * When running with 'meta' functionality, a target can be out-of-date
   1039  * if any of the references in its meta data file is more recent.
   1040  * We have to track the latestdir on a per-process basis.
   1041  */
   1042 #define LCWD_VNAME_FMT ".meta.%d.lcwd"
   1043 #define LDIR_VNAME_FMT ".meta.%d.ldir"
   1044 
   1045 /*
   1046  * It is possible that a .meta file is corrupted,
   1047  * if we detect this we want to reproduce it.
   1048  * Setting oodate true will have that effect.
   1049  */
   1050 #define CHECK_VALID_META(p) if (!(p != NULL && *p != '\0')) { \
   1051     warnx("%s: %d: malformed", fname, lineno); \
   1052     oodate = true; \
   1053     continue; \
   1054     }
   1055 
   1056 #define DEQUOTE(p) if (*p == '\'') {	\
   1057     char *ep; \
   1058     p++; \
   1059     if ((ep = strchr(p, '\'')) != NULL) \
   1060 	*ep = '\0'; \
   1061     }
   1062 
   1063 static void
   1064 append_if_new(StringList *list, const char *str)
   1065 {
   1066     StringListNode *ln;
   1067 
   1068     for (ln = list->first; ln != NULL; ln = ln->next)
   1069 	if (strcmp(ln->datum, str) == 0)
   1070 	    return;
   1071     Lst_Append(list, bmake_strdup(str));
   1072 }
   1073 
   1074 bool
   1075 meta_oodate(GNode *gn, bool oodate)
   1076 {
   1077     static char *tmpdir = NULL;
   1078     static char cwd[MAXPATHLEN];
   1079     char lcwd_vname[64];
   1080     char ldir_vname[64];
   1081     char lcwd[MAXPATHLEN];
   1082     char latestdir[MAXPATHLEN];
   1083     char fname[MAXPATHLEN];
   1084     char fname1[MAXPATHLEN];
   1085     char fname2[MAXPATHLEN];
   1086     char fname3[MAXPATHLEN];
   1087     FStr dname;
   1088     const char *tname;
   1089     char *p;
   1090     char *link_src;
   1091     char *move_target;
   1092     static size_t cwdlen = 0;
   1093     static size_t tmplen = 0;
   1094     FILE *fp;
   1095     bool needOODATE = false;
   1096     StringList missingFiles;
   1097     bool have_filemon = false;
   1098 
   1099     if (oodate)
   1100 	return oodate;		/* we're done */
   1101 
   1102     dname = Var_Value(gn, ".OBJDIR");
   1103     tname = GNode_VarTarget(gn);
   1104 
   1105     /* if this succeeds fname3 is realpath of dname */
   1106     if (!meta_needed(gn, dname.str, fname3, false))
   1107 	goto oodate_out;
   1108     dname.str = fname3;
   1109 
   1110     Lst_Init(&missingFiles);
   1111 
   1112     /*
   1113      * We need to check if the target is out-of-date. This includes
   1114      * checking if the expanded command has changed. This in turn
   1115      * requires that all variables are set in the same way that they
   1116      * would be if the target needs to be re-built.
   1117      */
   1118     GNode_SetLocalVars(gn);
   1119 
   1120     meta_name(fname, sizeof fname, dname.str, tname, dname.str);
   1121 
   1122 #ifdef DEBUG_META_MODE
   1123     DEBUG1(META, "meta_oodate: %s\n", fname);
   1124 #endif
   1125 
   1126     if ((fp = fopen(fname, "r")) != NULL) {
   1127 	static char *buf = NULL;
   1128 	static size_t bufsz;
   1129 	int lineno = 0;
   1130 	int lastpid = 0;
   1131 	int pid;
   1132 	int x;
   1133 	StringListNode *cmdNode;
   1134 	struct cached_stat cst;
   1135 
   1136 	if (buf == NULL) {
   1137 	    bufsz = 8 * BUFSIZ;
   1138 	    buf = bmake_malloc(bufsz);
   1139 	}
   1140 
   1141 	if (cwdlen == 0) {
   1142 	    if (getcwd(cwd, sizeof cwd) == NULL)
   1143 		err(1, "Could not get current working directory");
   1144 	    cwdlen = strlen(cwd);
   1145 	}
   1146 	strlcpy(lcwd, cwd, sizeof lcwd);
   1147 	strlcpy(latestdir, cwd, sizeof latestdir);
   1148 
   1149 	if (tmpdir == NULL) {
   1150 	    tmpdir = getTmpdir();
   1151 	    tmplen = strlen(tmpdir);
   1152 	}
   1153 
   1154 	/* we want to track all the .meta we read */
   1155 	Global_Append(".MAKE.META.FILES", fname);
   1156 
   1157 	cmdNode = gn->commands.first;
   1158 	while (!oodate && (x = fgetLine(&buf, &bufsz, 0, fp)) > 0) {
   1159 	    lineno++;
   1160 	    if (buf[x - 1] == '\n')
   1161 		buf[x - 1] = '\0';
   1162 	    else {
   1163 		warnx("%s: %d: line truncated at %u", fname, lineno, x);
   1164 		oodate = true;
   1165 		break;
   1166 	    }
   1167 	    link_src = NULL;
   1168 	    move_target = NULL;
   1169 	    /* Find the start of the build monitor section. */
   1170 	    if (!have_filemon) {
   1171 		if (strncmp(buf, "-- filemon", 10) == 0) {
   1172 		    have_filemon = true;
   1173 		    continue;
   1174 		}
   1175 		if (strncmp(buf, "# buildmon", 10) == 0) {
   1176 		    have_filemon = true;
   1177 		    continue;
   1178 		}
   1179 	    }
   1180 
   1181 	    /* Delimit the record type. */
   1182 	    p = buf;
   1183 #ifdef DEBUG_META_MODE
   1184 	    DEBUG3(META, "%s: %d: %s\n", fname, lineno, buf);
   1185 #endif
   1186 	    strsep(&p, " ");
   1187 	    if (have_filemon) {
   1188 		/*
   1189 		 * We are in the 'filemon' output section.
   1190 		 * Each record from filemon follows the general form:
   1191 		 *
   1192 		 * <key> <pid> <data>
   1193 		 *
   1194 		 * Where:
   1195 		 * <key> is a single letter, denoting the syscall.
   1196 		 * <pid> is the process that made the syscall.
   1197 		 * <data> is the arguments (of interest).
   1198 		 */
   1199 		switch(buf[0]) {
   1200 		case '#':		/* comment */
   1201 		case 'V':		/* version */
   1202 		    break;
   1203 		default:
   1204 		    /*
   1205 		     * We need to track pathnames per-process.
   1206 		     *
   1207 		     * Each process run by make starts off in the 'CWD'
   1208 		     * recorded in the .meta file, if it chdirs ('C')
   1209 		     * elsewhere we need to track that - but only for
   1210 		     * that process.  If it forks ('F'), we initialize
   1211 		     * the child to have the same cwd as its parent.
   1212 		     *
   1213 		     * We also need to track the 'latestdir' of
   1214 		     * interest.  This is usually the same as cwd, but
   1215 		     * not if a process is reading directories.
   1216 		     *
   1217 		     * Each time we spot a different process ('pid')
   1218 		     * we save the current value of 'latestdir' in a
   1219 		     * variable qualified by 'lastpid', and
   1220 		     * re-initialize 'latestdir' to any pre-saved
   1221 		     * value for the current 'pid' and 'CWD' if none.
   1222 		     */
   1223 		    CHECK_VALID_META(p);
   1224 		    pid = atoi(p);
   1225 		    if (pid > 0 && pid != lastpid) {
   1226 			FStr ldir;
   1227 
   1228 			if (lastpid > 0) {
   1229 			    /* We need to remember these. */
   1230 			    Global_SetExpand(lcwd_vname, lcwd);
   1231 			    Global_SetExpand(ldir_vname, latestdir);
   1232 			}
   1233 			snprintf(lcwd_vname, sizeof lcwd_vname, LCWD_VNAME_FMT, pid);
   1234 			snprintf(ldir_vname, sizeof ldir_vname, LDIR_VNAME_FMT, pid);
   1235 			lastpid = pid;
   1236 			ldir = Var_Value(SCOPE_GLOBAL, ldir_vname);
   1237 			if (ldir.str != NULL) {
   1238 			    strlcpy(latestdir, ldir.str, sizeof latestdir);
   1239 			    FStr_Done(&ldir);
   1240 			}
   1241 			ldir = Var_Value(SCOPE_GLOBAL, lcwd_vname);
   1242 			if (ldir.str != NULL) {
   1243 			    strlcpy(lcwd, ldir.str, sizeof lcwd);
   1244 			    FStr_Done(&ldir);
   1245 			}
   1246 		    }
   1247 		    /* Skip past the pid. */
   1248 		    if (strsep(&p, " ") == NULL)
   1249 			continue;
   1250 #ifdef DEBUG_META_MODE
   1251 		    if (DEBUG(META))
   1252 			debug_printf("%s: %d: %d: %c: cwd=%s lcwd=%s ldir=%s\n",
   1253 				     fname, lineno,
   1254 				     pid, buf[0], cwd, lcwd, latestdir);
   1255 #endif
   1256 		    break;
   1257 		}
   1258 
   1259 		CHECK_VALID_META(p);
   1260 
   1261 		/* Process according to record type. */
   1262 		switch (buf[0]) {
   1263 		case 'X':		/* eXit */
   1264 		    Var_DeleteExpand(SCOPE_GLOBAL, lcwd_vname);
   1265 		    Var_DeleteExpand(SCOPE_GLOBAL, ldir_vname);
   1266 		    lastpid = 0;	/* no need to save ldir_vname */
   1267 		    break;
   1268 
   1269 		case 'F':		/* [v]Fork */
   1270 		    {
   1271 			char cldir[64];
   1272 			int child;
   1273 
   1274 			child = atoi(p);
   1275 			if (child > 0) {
   1276 			    snprintf(cldir, sizeof cldir, LCWD_VNAME_FMT, child);
   1277 			    Global_SetExpand(cldir, lcwd);
   1278 			    snprintf(cldir, sizeof cldir, LDIR_VNAME_FMT, child);
   1279 			    Global_SetExpand(cldir, latestdir);
   1280 #ifdef DEBUG_META_MODE
   1281 			    if (DEBUG(META))
   1282 				debug_printf(
   1283 					"%s: %d: %d: cwd=%s lcwd=%s ldir=%s\n",
   1284 					fname, lineno,
   1285 					child, cwd, lcwd, latestdir);
   1286 #endif
   1287 			}
   1288 		    }
   1289 		    break;
   1290 
   1291 		case 'C':		/* Chdir */
   1292 		    /* Update lcwd and latest directory. */
   1293 		    strlcpy(latestdir, p, sizeof latestdir);
   1294 		    strlcpy(lcwd, p, sizeof lcwd);
   1295 		    Global_SetExpand(lcwd_vname, lcwd);
   1296 		    Global_SetExpand(ldir_vname, lcwd);
   1297 #ifdef DEBUG_META_MODE
   1298 		    DEBUG4(META, "%s: %d: cwd=%s ldir=%s\n",
   1299 			   fname, lineno, cwd, lcwd);
   1300 #endif
   1301 		    break;
   1302 
   1303 		case 'M':		/* renaMe */
   1304 		    /*
   1305 		     * For 'M'oves we want to check
   1306 		     * the src as for 'R'ead
   1307 		     * and the target as for 'W'rite.
   1308 		     */
   1309 		    {
   1310 			char *cp = p;	/* save this for a second */
   1311 			/* now get target */
   1312 			if (strsep(&p, " ") == NULL)
   1313 			    continue;
   1314 			CHECK_VALID_META(p);
   1315 			move_target = p;
   1316 			p = cp;
   1317 		    }
   1318 		    /* 'L' and 'M' put single quotes around the args */
   1319 		    DEQUOTE(p);
   1320 		    DEQUOTE(move_target);
   1321 		    /* FALLTHROUGH */
   1322 		case 'D':		/* unlink */
   1323 		    if (*p == '/') {
   1324 			/* remove any missingFiles entries that match p */
   1325 			StringListNode *ln = missingFiles.first;
   1326 			while (ln != NULL) {
   1327 			    StringListNode *next = ln->next;
   1328 			    if (path_starts_with(ln->datum, p)) {
   1329 				free(ln->datum);
   1330 				Lst_Remove(&missingFiles, ln);
   1331 			    }
   1332 			    ln = next;
   1333 			}
   1334 		    }
   1335 		    if (buf[0] == 'M') {
   1336 			/* the target of the mv is a file 'W'ritten */
   1337 #ifdef DEBUG_META_MODE
   1338 			DEBUG2(META, "meta_oodate: M %s -> %s\n",
   1339 			       p, move_target);
   1340 #endif
   1341 			p = move_target;
   1342 			goto check_write;
   1343 		    }
   1344 		    break;
   1345 		case 'L':		/* Link */
   1346 		    /*
   1347 		     * For 'L'inks check
   1348 		     * the src as for 'R'ead
   1349 		     * and the target as for 'W'rite.
   1350 		     */
   1351 		    link_src = p;
   1352 		    /* now get target */
   1353 		    if (strsep(&p, " ") == NULL)
   1354 			continue;
   1355 		    CHECK_VALID_META(p);
   1356 		    /* 'L' and 'M' put single quotes around the args */
   1357 		    DEQUOTE(p);
   1358 		    DEQUOTE(link_src);
   1359 #ifdef DEBUG_META_MODE
   1360 		    DEBUG2(META, "meta_oodate: L %s -> %s\n", link_src, p);
   1361 #endif
   1362 		    /* FALLTHROUGH */
   1363 		case 'W':		/* Write */
   1364 		check_write:
   1365 		    /*
   1366 		     * If a file we generated within our bailiwick
   1367 		     * but outside of .OBJDIR is missing,
   1368 		     * we need to do it again.
   1369 		     */
   1370 		    /* ignore non-absolute paths */
   1371 		    if (*p != '/')
   1372 			break;
   1373 
   1374 		    if (Lst_IsEmpty(&metaBailiwick))
   1375 			break;
   1376 
   1377 		    /* ignore cwd - normal dependencies handle those */
   1378 		    if (strncmp(p, cwd, cwdlen) == 0)
   1379 			break;
   1380 
   1381 		    if (!has_any_prefix(p, &metaBailiwick))
   1382 			break;
   1383 
   1384 		    /* tmpdir might be within */
   1385 		    if (tmplen > 0 && strncmp(p, tmpdir, tmplen) == 0)
   1386 			break;
   1387 
   1388 		    /* ignore anything containing the string "tmp" */
   1389 		    /* XXX: The arguments to strstr must be swapped. */
   1390 		    if (strstr("tmp", p) != NULL)
   1391 			break;
   1392 
   1393 		    if ((link_src != NULL && cached_lstat(p, &cst) < 0) ||
   1394 			(link_src == NULL && cached_stat(p, &cst) < 0)) {
   1395 			if (!meta_ignore(gn, p))
   1396 			    append_if_new(&missingFiles, p);
   1397 		    }
   1398 		    break;
   1399 		check_link_src:
   1400 		    p = link_src;
   1401 		    link_src = NULL;
   1402 #ifdef DEBUG_META_MODE
   1403 		    DEBUG1(META, "meta_oodate: L src %s\n", p);
   1404 #endif
   1405 		    /* FALLTHROUGH */
   1406 		case 'R':		/* Read */
   1407 		case 'E':		/* Exec */
   1408 		    /*
   1409 		     * Check for runtime files that can't
   1410 		     * be part of the dependencies because
   1411 		     * they are _expected_ to change.
   1412 		     */
   1413 		    if (meta_ignore(gn, p))
   1414 			break;
   1415 
   1416 		    /*
   1417 		     * The rest of the record is the file name.
   1418 		     * Check if it's not an absolute path.
   1419 		     */
   1420 		    {
   1421 			char *sdirs[4];
   1422 			char **sdp;
   1423 			int sdx = 0;
   1424 			bool found = false;
   1425 
   1426 			if (*p == '/') {
   1427 			    sdirs[sdx++] = p; /* done */
   1428 			} else {
   1429 			    if (strcmp(".", p) == 0)
   1430 				continue; /* no point */
   1431 
   1432 			    /* Check vs latestdir */
   1433 			    snprintf(fname1, sizeof fname1, "%s/%s", latestdir, p);
   1434 			    sdirs[sdx++] = fname1;
   1435 
   1436 			    if (strcmp(latestdir, lcwd) != 0) {
   1437 				/* Check vs lcwd */
   1438 				snprintf(fname2, sizeof fname2, "%s/%s", lcwd, p);
   1439 				sdirs[sdx++] = fname2;
   1440 			    }
   1441 			    if (strcmp(lcwd, cwd) != 0) {
   1442 				/* Check vs cwd */
   1443 				snprintf(fname3, sizeof fname3, "%s/%s", cwd, p);
   1444 				sdirs[sdx++] = fname3;
   1445 			    }
   1446 			}
   1447 			sdirs[sdx++] = NULL;
   1448 
   1449 			for (sdp = sdirs; *sdp != NULL && !found; sdp++) {
   1450 #ifdef DEBUG_META_MODE
   1451 			    DEBUG3(META, "%s: %d: looking for: %s\n",
   1452 				   fname, lineno, *sdp);
   1453 #endif
   1454 			    if (cached_stat(*sdp, &cst) == 0) {
   1455 				found = true;
   1456 				p = *sdp;
   1457 			    }
   1458 			}
   1459 			if (found) {
   1460 #ifdef DEBUG_META_MODE
   1461 			    DEBUG3(META, "%s: %d: found: %s\n",
   1462 				   fname, lineno, p);
   1463 #endif
   1464 			    if (!S_ISDIR(cst.cst_mode) &&
   1465 				cst.cst_mtime > gn->mtime) {
   1466 				DEBUG3(META, "%s: %d: file '%s' is newer than the target...\n",
   1467 				       fname, lineno, p);
   1468 				oodate = true;
   1469 			    } else if (S_ISDIR(cst.cst_mode)) {
   1470 				/* Update the latest directory. */
   1471 				cached_realpath(p, latestdir);
   1472 			    }
   1473 			} else if (errno == ENOENT && *p == '/' &&
   1474 				   strncmp(p, cwd, cwdlen) != 0) {
   1475 			    /*
   1476 			     * A referenced file outside of CWD is missing.
   1477 			     * We cannot catch every eventuality here...
   1478 			     */
   1479 			    append_if_new(&missingFiles, p);
   1480 			}
   1481 		    }
   1482 		    if (buf[0] == 'E') {
   1483 			/* previous latestdir is no longer relevant */
   1484 			strlcpy(latestdir, lcwd, sizeof latestdir);
   1485 		    }
   1486 		    break;
   1487 		default:
   1488 		    break;
   1489 		}
   1490 		if (!oodate && buf[0] == 'L' && link_src != NULL)
   1491 		    goto check_link_src;
   1492 	    } else if (strcmp(buf, "CMD") == 0) {
   1493 		/*
   1494 		 * Compare the current command with the one in the
   1495 		 * meta data file.
   1496 		 */
   1497 		if (cmdNode == NULL) {
   1498 		    DEBUG2(META, "%s: %d: there were more build commands in the meta data file than there are now...\n",
   1499 			   fname, lineno);
   1500 		    oodate = true;
   1501 		} else {
   1502 		    const char *cp;
   1503 		    char *cmd = cmdNode->datum;
   1504 		    bool hasOODATE = false;
   1505 
   1506 		    if (strstr(cmd, "$?") != NULL)
   1507 			hasOODATE = true;
   1508 		    else if ((cp = strstr(cmd, ".OODATE")) != NULL) {
   1509 			/* check for $[{(].OODATE[:)}] */
   1510 			if (cp > cmd + 2 && cp[-2] == '$')
   1511 			    hasOODATE = true;
   1512 		    }
   1513 		    if (hasOODATE) {
   1514 			needOODATE = true;
   1515 			DEBUG2(META, "%s: %d: cannot compare command using .OODATE\n",
   1516 			       fname, lineno);
   1517 		    }
   1518 		    (void)Var_Subst(cmd, gn, VARE_UNDEFERR, &cmd);
   1519 		    /* TODO: handle errors */
   1520 
   1521 		    if ((cp = strchr(cmd, '\n')) != NULL) {
   1522 			int n;
   1523 
   1524 			/*
   1525 			 * This command contains newlines, we need to
   1526 			 * fetch more from the .meta file before we
   1527 			 * attempt a comparison.
   1528 			 */
   1529 			/* first put the newline back at buf[x - 1] */
   1530 			buf[x - 1] = '\n';
   1531 			do {
   1532 			    /* now fetch the next line */
   1533 			    if ((n = fgetLine(&buf, &bufsz, x, fp)) <= 0)
   1534 				break;
   1535 			    x = n;
   1536 			    lineno++;
   1537 			    if (buf[x - 1] != '\n') {
   1538 				warnx("%s: %d: line truncated at %u", fname, lineno, x);
   1539 				break;
   1540 			    }
   1541 			    cp = strchr(cp + 1, '\n');
   1542 			} while (cp != NULL);
   1543 			if (buf[x - 1] == '\n')
   1544 			    buf[x - 1] = '\0';
   1545 		    }
   1546 		    if (p != NULL &&
   1547 			!hasOODATE &&
   1548 			!(gn->type & OP_NOMETA_CMP) &&
   1549 			(strcmp(p, cmd) != 0)) {
   1550 			DEBUG4(META, "%s: %d: a build command has changed\n%s\nvs\n%s\n",
   1551 			       fname, lineno, p, cmd);
   1552 			if (!metaIgnoreCMDs)
   1553 			    oodate = true;
   1554 		    }
   1555 		    free(cmd);
   1556 		    cmdNode = cmdNode->next;
   1557 		}
   1558 	    } else if (strcmp(buf, "CWD") == 0) {
   1559 		/*
   1560 		 * Check if there are extra commands now
   1561 		 * that weren't in the meta data file.
   1562 		 */
   1563 		if (!oodate && cmdNode != NULL) {
   1564 		    DEBUG2(META, "%s: %d: there are extra build commands now that weren't in the meta data file\n",
   1565 			   fname, lineno);
   1566 		    oodate = true;
   1567 		}
   1568 		CHECK_VALID_META(p);
   1569 		if (strcmp(p, cwd) != 0) {
   1570 		    DEBUG4(META, "%s: %d: the current working directory has changed from '%s' to '%s'\n",
   1571 			   fname, lineno, p, curdir);
   1572 		    oodate = true;
   1573 		}
   1574 	    }
   1575 	}
   1576 
   1577 	fclose(fp);
   1578 	if (!Lst_IsEmpty(&missingFiles)) {
   1579 	    DEBUG2(META, "%s: missing files: %s...\n",
   1580 		   fname, (char *)missingFiles.first->datum);
   1581 	    oodate = true;
   1582 	}
   1583 	if (!oodate && !have_filemon && filemonMissing) {
   1584 	    DEBUG1(META, "%s: missing filemon data\n", fname);
   1585 	    oodate = true;
   1586 	}
   1587     } else {
   1588 	if (writeMeta && (metaMissing || (gn->type & OP_META))) {
   1589 	    const char *cp = NULL;
   1590 
   1591 	    /* if target is in .CURDIR we do not need a meta file */
   1592 	    if (gn->path != NULL && (cp = strrchr(gn->path, '/')) != NULL &&
   1593 		(cp > gn->path)) {
   1594 		if (strncmp(curdir, gn->path, (size_t)(cp - gn->path)) != 0) {
   1595 		    cp = NULL;		/* not in .CURDIR */
   1596 		}
   1597 	    }
   1598 	    if (cp == NULL) {
   1599 		DEBUG1(META, "%s: required but missing\n", fname);
   1600 		oodate = true;
   1601 		needOODATE = true;	/* assume the worst */
   1602 	    }
   1603 	}
   1604     }
   1605 
   1606     Lst_DoneCall(&missingFiles, free);
   1607 
   1608     if (oodate && needOODATE) {
   1609 	/*
   1610 	 * Target uses .OODATE which is empty; or we wouldn't be here.
   1611 	 * We have decided it is oodate, so .OODATE needs to be set.
   1612 	 * All we can sanely do is set it to .ALLSRC.
   1613 	 */
   1614 	Var_Delete(gn, OODATE);
   1615 	Var_Set(gn, OODATE, GNode_VarAllsrc(gn));
   1616     }
   1617 
   1618  oodate_out:
   1619     FStr_Done(&dname);
   1620     return oodate;
   1621 }
   1622 
   1623 /* support for compat mode */
   1624 
   1625 static int childPipe[2];
   1626 
   1627 void
   1628 meta_compat_start(void)
   1629 {
   1630 #ifdef USE_FILEMON_ONCE
   1631     /*
   1632      * We need to re-open filemon for each cmd.
   1633      */
   1634     BuildMon *pbm = &Mybm;
   1635 
   1636     if (pbm->mfp != NULL && useFilemon) {
   1637 	meta_open_filemon(pbm);
   1638     } else {
   1639 	pbm->mon_fd = -1;
   1640 	pbm->filemon = NULL;
   1641     }
   1642 #endif
   1643     if (pipe(childPipe) < 0)
   1644 	Punt("Cannot create pipe: %s", strerror(errno));
   1645     /* Set close-on-exec flag for both */
   1646     (void)fcntl(childPipe[0], F_SETFD, FD_CLOEXEC);
   1647     (void)fcntl(childPipe[1], F_SETFD, FD_CLOEXEC);
   1648 }
   1649 
   1650 void
   1651 meta_compat_child(void)
   1652 {
   1653     meta_job_child(NULL);
   1654     if (dup2(childPipe[1], 1) < 0 || dup2(1, 2) < 0)
   1655 	execDie("dup2", "pipe");
   1656 }
   1657 
   1658 void
   1659 meta_compat_parent(pid_t child)
   1660 {
   1661     int outfd, metafd, maxfd, nfds;
   1662     char buf[BUFSIZ+1];
   1663     fd_set readfds;
   1664 
   1665     meta_job_parent(NULL, child);
   1666     close(childPipe[1]);			/* child side */
   1667     outfd = childPipe[0];
   1668 #ifdef USE_FILEMON
   1669     metafd = Mybm.filemon != NULL ? filemon_readfd(Mybm.filemon) : -1;
   1670 #else
   1671     metafd = -1;
   1672 #endif
   1673     maxfd = -1;
   1674     if (outfd > maxfd)
   1675 	    maxfd = outfd;
   1676     if (metafd > maxfd)
   1677 	    maxfd = metafd;
   1678 
   1679     while (outfd != -1 || metafd != -1) {
   1680 	FD_ZERO(&readfds);
   1681 	if (outfd != -1) {
   1682 	    FD_SET(outfd, &readfds);
   1683 	}
   1684 	if (metafd != -1) {
   1685 	    FD_SET(metafd, &readfds);
   1686 	}
   1687 	nfds = select(maxfd + 1, &readfds, NULL, NULL, NULL);
   1688 	if (nfds == -1) {
   1689 	    if (errno == EINTR)
   1690 		continue;
   1691 	    err(1, "select");
   1692 	}
   1693 
   1694 	if (outfd != -1 && FD_ISSET(outfd, &readfds) != 0) do {
   1695 	    /* XXX this is not line-buffered */
   1696 	    ssize_t nread = read(outfd, buf, sizeof buf - 1);
   1697 	    if (nread == -1)
   1698 		err(1, "read");
   1699 	    if (nread == 0) {
   1700 		close(outfd);
   1701 		outfd = -1;
   1702 		break;
   1703 	    }
   1704 	    fwrite(buf, 1, (size_t)nread, stdout);
   1705 	    fflush(stdout);
   1706 	    buf[nread] = '\0';
   1707 	    meta_job_output(NULL, buf, "");
   1708 	} while (/*CONSTCOND*/false);
   1709 	if (metafd != -1 && FD_ISSET(metafd, &readfds) != 0) {
   1710 	    if (meta_job_event(NULL) <= 0)
   1711 		metafd = -1;
   1712 	}
   1713     }
   1714 }
   1715 
   1716 #endif /* USE_META */
   1717