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meta.c revision 1.180
      1 /*      $NetBSD: meta.c,v 1.180 2021/04/03 11:08:40 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;
    248     char *cp;
    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 ((cp = strrchr(tname, '/')) != NULL) {
    261 	if (cached_realpath(tname, buf) != NULL) {
    262 	    if ((rp = strrchr(buf, '/')) != NULL) {
    263 		rp++;
    264 		cp++;
    265 		if (strcmp(cp, rp) != 0)
    266 		    strlcpy(rp, cp, 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 ${.MAKE}
    316  * Bypassed if target is flagged .MAKE
    317  */
    318 static bool
    319 is_submake(const char *cmd, GNode *gn)
    320 {
    321     static const char *p_make = NULL;
    322     static size_t p_len;
    323     char *mp = NULL;
    324     char *cp;
    325     char *cp2;
    326     bool rc = false;
    327 
    328     if (p_make == NULL) {
    329 	p_make = Var_Value(gn, ".MAKE").str;
    330 	p_len = strlen(p_make);
    331     }
    332     cp = strchr(cmd, '$');
    333     if (cp != NULL) {
    334 	(void)Var_Subst(cmd, gn, VARE_WANTRES, &mp);
    335 	/* TODO: handle errors */
    336 	cmd = mp;
    337     }
    338     cp2 = strstr(cmd, p_make);
    339     if (cp2 != NULL) {
    340 	switch (cp2[p_len]) {
    341 	case '\0':
    342 	case ' ':
    343 	case '\t':
    344 	case '\n':
    345 	    rc = true;
    346 	    break;
    347 	}
    348 	if (cp2 > cmd && rc) {
    349 	    switch (cp2[-1]) {
    350 	    case ' ':
    351 	    case '\t':
    352 	    case '\n':
    353 		break;
    354 	    default:
    355 		rc = false;		/* no match */
    356 		break;
    357 	    }
    358 	}
    359     }
    360     free(mp);
    361     return rc;
    362 }
    363 
    364 static bool
    365 any_is_submake(GNode *gn)
    366 {
    367     StringListNode *ln;
    368 
    369     for (ln = gn->commands.first; ln != NULL; ln = ln->next)
    370 	if (is_submake(ln->datum, gn))
    371 	    return true;
    372     return false;
    373 }
    374 
    375 static void
    376 printCMD(const char *ucmd, FILE *fp, GNode *gn)
    377 {
    378     FStr xcmd = FStr_InitRefer(ucmd);
    379 
    380     if (strchr(ucmd, '$') != NULL) {
    381     	char *expanded;
    382 	(void)Var_Subst(ucmd, gn, VARE_WANTRES, &expanded);
    383 	/* TODO: handle errors */
    384 	xcmd = FStr_InitOwn(expanded);
    385     }
    386 
    387     fprintf(fp, "CMD %s\n", xcmd.str);
    388     FStr_Done(&xcmd);
    389 }
    390 
    391 static void
    392 printCMDs(GNode *gn, FILE *fp)
    393 {
    394     StringListNode *ln;
    395 
    396     for (ln = gn->commands.first; ln != NULL; ln = ln->next)
    397 	printCMD(ln->datum, fp, gn);
    398 }
    399 
    400 /*
    401  * Certain node types never get a .meta file
    402  */
    403 #define SKIP_META_TYPE(_type) do { \
    404     if ((gn->type & __CONCAT(OP_, _type))) { \
    405 	if (verbose) { \
    406 	    debug_printf("Skipping meta for %s: .%s\n", \
    407 		    gn->name, __STRING(_type)); \
    408 	} \
    409 	return false; \
    410     } \
    411 } while (/*CONSTCOND*/false)
    412 
    413 
    414 /*
    415  * Do we need/want a .meta file ?
    416  */
    417 static bool
    418 meta_needed(GNode *gn, const char *dname,
    419 	    char *objdir_realpath, bool verbose)
    420 {
    421     struct cached_stat cst;
    422 
    423     if (verbose)
    424 	verbose = DEBUG(META);
    425 
    426     /* This may be a phony node which we don't want meta data for... */
    427     /* Skip .meta for .BEGIN, .END, .ERROR etc as well. */
    428     /* Or it may be explicitly flagged as .NOMETA */
    429     SKIP_META_TYPE(NOMETA);
    430     /* Unless it is explicitly flagged as .META */
    431     if (!(gn->type & OP_META)) {
    432 	SKIP_META_TYPE(PHONY);
    433 	SKIP_META_TYPE(SPECIAL);
    434 	SKIP_META_TYPE(MAKE);
    435     }
    436 
    437     /* Check if there are no commands to execute. */
    438     if (Lst_IsEmpty(&gn->commands)) {
    439 	if (verbose)
    440 	    debug_printf("Skipping meta for %s: no commands\n", gn->name);
    441 	return false;
    442     }
    443     if ((gn->type & (OP_META|OP_SUBMAKE)) == OP_SUBMAKE) {
    444 	/* OP_SUBMAKE is a bit too aggressive */
    445 	if (any_is_submake(gn)) {
    446 	    DEBUG1(META, "Skipping meta for %s: .SUBMAKE\n", gn->name);
    447 	    return false;
    448 	}
    449     }
    450 
    451     /* The object directory may not exist. Check it.. */
    452     if (cached_stat(dname, &cst) != 0) {
    453 	if (verbose)
    454 	    debug_printf("Skipping meta for %s: no .OBJDIR\n", gn->name);
    455 	return false;
    456     }
    457 
    458     /* make sure these are canonical */
    459     if (cached_realpath(dname, objdir_realpath) != NULL)
    460 	dname = objdir_realpath;
    461 
    462     /* If we aren't in the object directory, don't create a meta file. */
    463     if (!metaCurdirOk && strcmp(curdir, dname) == 0) {
    464 	if (verbose)
    465 	    debug_printf("Skipping meta for %s: .OBJDIR == .CURDIR\n",
    466 			 gn->name);
    467 	return false;
    468     }
    469     return true;
    470 }
    471 
    472 
    473 static FILE *
    474 meta_create(BuildMon *pbm, GNode *gn)
    475 {
    476     FILE *fp;
    477     char buf[MAXPATHLEN];
    478     char objdir_realpath[MAXPATHLEN];
    479     char **ptr;
    480     FStr dname;
    481     const char *tname;
    482     char *fname;
    483     const char *cp;
    484 
    485     fp = NULL;
    486 
    487     dname = Var_Value(gn, ".OBJDIR");
    488     tname = GNode_VarTarget(gn);
    489 
    490     /* if this succeeds objdir_realpath is realpath of dname */
    491     if (!meta_needed(gn, dname.str, objdir_realpath, true))
    492 	goto out;
    493     dname.str = objdir_realpath;
    494 
    495     if (metaVerbose) {
    496 	char *mp;
    497 
    498 	/* Describe the target we are building */
    499 	(void)Var_Subst("${" MAKE_META_PREFIX "}", gn, VARE_WANTRES, &mp);
    500 	/* TODO: handle errors */
    501 	if (mp[0] != '\0')
    502 	    fprintf(stdout, "%s\n", mp);
    503 	free(mp);
    504     }
    505     /* Get the basename of the target */
    506     cp = str_basename(tname);
    507 
    508     fflush(stdout);
    509 
    510     if (!writeMeta)
    511 	/* Don't create meta data. */
    512 	goto out;
    513 
    514     fname = meta_name(pbm->meta_fname, sizeof pbm->meta_fname,
    515 		      dname.str, tname, objdir_realpath);
    516 
    517 #ifdef DEBUG_META_MODE
    518     DEBUG1(META, "meta_create: %s\n", fname);
    519 #endif
    520 
    521     if ((fp = fopen(fname, "w")) == NULL)
    522 	err(1, "Could not open meta file '%s'", fname);
    523 
    524     fprintf(fp, "# Meta data file %s\n", fname);
    525 
    526     printCMDs(gn, fp);
    527 
    528     fprintf(fp, "CWD %s\n", getcwd(buf, sizeof buf));
    529     fprintf(fp, "TARGET %s\n", tname);
    530     cp = GNode_VarOodate(gn);
    531     if (cp != NULL && *cp != '\0') {
    532 	fprintf(fp, "OODATE %s\n", cp);
    533     }
    534     if (metaEnv) {
    535 	for (ptr = environ; *ptr != NULL; ptr++)
    536 	    fprintf(fp, "ENV %s\n", *ptr);
    537     }
    538 
    539     fprintf(fp, "-- command output --\n");
    540     fflush(fp);
    541 
    542     Global_Append(".MAKE.META.FILES", fname);
    543     Global_Append(".MAKE.META.CREATED", fname);
    544 
    545     gn->type |= OP_META;		/* in case anyone wants to know */
    546     if (metaSilent) {
    547 	    gn->type |= OP_SILENT;
    548     }
    549  out:
    550     FStr_Done(&dname);
    551 
    552     return fp;
    553 }
    554 
    555 static bool
    556 boolValue(char *s)
    557 {
    558     switch(*s) {
    559     case '0':
    560     case 'N':
    561     case 'n':
    562     case 'F':
    563     case 'f':
    564 	return false;
    565     }
    566     return true;
    567 }
    568 
    569 /*
    570  * Initialization we need before reading makefiles.
    571  */
    572 void
    573 meta_init(void)
    574 {
    575 #ifdef USE_FILEMON
    576 	/* this allows makefiles to test if we have filemon support */
    577 	Global_Set(".MAKE.PATH_FILEMON", filemon_path());
    578 #endif
    579 }
    580 
    581 
    582 #define get_mode_bf(bf, token) \
    583     if ((cp = strstr(make_mode, token)) != NULL) \
    584 	bf = boolValue(cp + sizeof (token) - 1)
    585 
    586 /*
    587  * Initialization we need after reading makefiles.
    588  */
    589 void
    590 meta_mode_init(const char *make_mode)
    591 {
    592     static bool once = false;
    593     char *cp;
    594     FStr value;
    595 
    596     useMeta = true;
    597     useFilemon = true;
    598     writeMeta = true;
    599 
    600     if (make_mode != NULL) {
    601 	if (strstr(make_mode, "env") != NULL)
    602 	    metaEnv = true;
    603 	if (strstr(make_mode, "verb") != NULL)
    604 	    metaVerbose = true;
    605 	if (strstr(make_mode, "read") != NULL)
    606 	    writeMeta = false;
    607 	if (strstr(make_mode, "nofilemon") != NULL)
    608 	    useFilemon = false;
    609 	if (strstr(make_mode, "ignore-cmd") != NULL)
    610 	    metaIgnoreCMDs = true;
    611 	if (useFilemon)
    612 	    get_mode_bf(filemonMissing, "missing-filemon=");
    613 	get_mode_bf(metaCurdirOk, "curdirok=");
    614 	get_mode_bf(metaMissing, "missing-meta=");
    615 	get_mode_bf(metaSilent, "silent=");
    616     }
    617     if (metaVerbose && !Var_Exists(SCOPE_GLOBAL, MAKE_META_PREFIX)) {
    618 	/*
    619 	 * The default value for MAKE_META_PREFIX
    620 	 * prints the absolute path of the target.
    621 	 * This works be cause :H will generate '.' if there is no /
    622 	 * and :tA will resolve that to cwd.
    623 	 */
    624 	Global_Set(MAKE_META_PREFIX,
    625 	    "Building ${.TARGET:H:tA}/${.TARGET:T}");
    626     }
    627     if (once)
    628 	return;
    629     once = true;
    630     memset(&Mybm, 0, sizeof Mybm);
    631     /*
    632      * We consider ourselves master of all within ${.MAKE.META.BAILIWICK}
    633      */
    634     (void)Var_Subst("${.MAKE.META.BAILIWICK:O:u:tA}",
    635 		    SCOPE_GLOBAL, VARE_WANTRES, &metaBailiwickStr);
    636     /* TODO: handle errors */
    637     str2Lst_Append(&metaBailiwick, metaBailiwickStr);
    638     /*
    639      * We ignore any paths that start with ${.MAKE.META.IGNORE_PATHS}
    640      */
    641     Global_Append(MAKE_META_IGNORE_PATHS,
    642 	       "/dev /etc /proc /tmp /var/run /var/tmp ${TMPDIR}");
    643     (void)Var_Subst("${" MAKE_META_IGNORE_PATHS ":O:u:tA}",
    644 		    SCOPE_GLOBAL, VARE_WANTRES, &metaIgnorePathsStr);
    645     /* TODO: handle errors */
    646     str2Lst_Append(&metaIgnorePaths, metaIgnorePathsStr);
    647 
    648     /*
    649      * We ignore any paths that match ${.MAKE.META.IGNORE_PATTERNS}
    650      */
    651     value = Var_Value(SCOPE_GLOBAL, MAKE_META_IGNORE_PATTERNS);
    652     if (value.str != NULL) {
    653 	metaIgnorePatterns = true;
    654 	FStr_Done(&value);
    655     }
    656     value = Var_Value(SCOPE_GLOBAL, MAKE_META_IGNORE_FILTER);
    657     if (value.str != NULL) {
    658 	metaIgnoreFilter = true;
    659 	FStr_Done(&value);
    660     }
    661 }
    662 
    663 /*
    664  * In each case below we allow for job==NULL
    665  */
    666 void
    667 meta_job_start(Job *job, GNode *gn)
    668 {
    669     BuildMon *pbm;
    670 
    671     if (job != NULL) {
    672 	pbm = &job->bm;
    673     } else {
    674 	pbm = &Mybm;
    675     }
    676     pbm->mfp = meta_create(pbm, gn);
    677 #ifdef USE_FILEMON_ONCE
    678     /* compat mode we open the filemon dev once per command */
    679     if (job == NULL)
    680 	return;
    681 #endif
    682 #ifdef USE_FILEMON
    683     if (pbm->mfp != NULL && useFilemon) {
    684 	meta_open_filemon(pbm);
    685     } else {
    686 	pbm->mon_fd = -1;
    687 	pbm->filemon = NULL;
    688     }
    689 #endif
    690 }
    691 
    692 /*
    693  * The child calls this before doing anything.
    694  * It does not disturb our state.
    695  */
    696 void
    697 meta_job_child(Job *job)
    698 {
    699 #ifdef USE_FILEMON
    700     BuildMon *pbm;
    701 
    702     if (job != NULL) {
    703 	pbm = &job->bm;
    704     } else {
    705 	pbm = &Mybm;
    706     }
    707     if (pbm->mfp != NULL) {
    708 	close(fileno(pbm->mfp));
    709 	if (useFilemon && pbm->filemon != NULL) {
    710 	    pid_t pid;
    711 
    712 	    pid = getpid();
    713 	    if (filemon_setpid_child(pbm->filemon, pid) == -1) {
    714 		err(1, "Could not set filemon pid!");
    715 	    }
    716 	}
    717     }
    718 #endif
    719 }
    720 
    721 void
    722 meta_job_parent(Job *job, pid_t pid)
    723 {
    724 #if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
    725     BuildMon *pbm;
    726 
    727     if (job != NULL) {
    728 	pbm = &job->bm;
    729     } else {
    730 	pbm = &Mybm;
    731     }
    732     if (useFilemon && pbm->filemon != NULL) {
    733 	filemon_setpid_parent(pbm->filemon, pid);
    734     }
    735 #endif
    736 }
    737 
    738 int
    739 meta_job_fd(Job *job)
    740 {
    741 #if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
    742     BuildMon *pbm;
    743 
    744     if (job != NULL) {
    745 	pbm = &job->bm;
    746     } else {
    747 	pbm = &Mybm;
    748     }
    749     if (useFilemon && pbm->filemon != NULL) {
    750 	return filemon_readfd(pbm->filemon);
    751     }
    752 #endif
    753     return -1;
    754 }
    755 
    756 int
    757 meta_job_event(Job *job)
    758 {
    759 #if defined(USE_FILEMON) && !defined(USE_FILEMON_DEV)
    760     BuildMon *pbm;
    761 
    762     if (job != NULL) {
    763 	pbm = &job->bm;
    764     } else {
    765 	pbm = &Mybm;
    766     }
    767     if (useFilemon && pbm->filemon != NULL) {
    768 	return filemon_process(pbm->filemon);
    769     }
    770 #endif
    771     return 0;
    772 }
    773 
    774 void
    775 meta_job_error(Job *job, GNode *gn, bool ignerr, int status)
    776 {
    777     char cwd[MAXPATHLEN];
    778     BuildMon *pbm;
    779 
    780     if (job != NULL) {
    781 	pbm = &job->bm;
    782 	if (gn == NULL)
    783 	    gn = job->node;
    784     } else {
    785 	pbm = &Mybm;
    786     }
    787     if (pbm->mfp != NULL) {
    788 	fprintf(pbm->mfp, "\n*** Error code %d%s\n",
    789 		status, ignerr ? "(ignored)" : "");
    790     }
    791     if (gn != NULL)
    792 	Global_Set(".ERROR_TARGET", GNode_Path(gn));
    793     getcwd(cwd, sizeof cwd);
    794     Global_Set(".ERROR_CWD", cwd);
    795     if (pbm->meta_fname[0] != '\0') {
    796 	Global_Set(".ERROR_META_FILE", pbm->meta_fname);
    797     }
    798     meta_job_finish(job);
    799 }
    800 
    801 void
    802 meta_job_output(Job *job, char *cp, const char *nl)
    803 {
    804     BuildMon *pbm;
    805 
    806     if (job != NULL) {
    807 	pbm = &job->bm;
    808     } else {
    809 	pbm = &Mybm;
    810     }
    811     if (pbm->mfp != NULL) {
    812 	if (metaVerbose) {
    813 	    static char *meta_prefix = NULL;
    814 	    static size_t meta_prefix_len;
    815 
    816 	    if (meta_prefix == NULL) {
    817 		char *cp2;
    818 
    819 		(void)Var_Subst("${" MAKE_META_PREFIX "}",
    820 				SCOPE_GLOBAL, VARE_WANTRES, &meta_prefix);
    821 		/* TODO: handle errors */
    822 		if ((cp2 = strchr(meta_prefix, '$')) != NULL)
    823 		    meta_prefix_len = (size_t)(cp2 - meta_prefix);
    824 		else
    825 		    meta_prefix_len = strlen(meta_prefix);
    826 	    }
    827 	    if (strncmp(cp, meta_prefix, meta_prefix_len) == 0) {
    828 		cp = strchr(cp + 1, '\n');
    829 		if (cp == NULL)
    830 		    return;
    831 		cp++;
    832 	    }
    833 	}
    834 	fprintf(pbm->mfp, "%s%s", cp, nl);
    835     }
    836 }
    837 
    838 int
    839 meta_cmd_finish(void *pbmp)
    840 {
    841     int error = 0;
    842     BuildMon *pbm = pbmp;
    843 #ifdef USE_FILEMON
    844     int x;
    845 #endif
    846 
    847     if (pbm == NULL)
    848 	pbm = &Mybm;
    849 
    850 #ifdef USE_FILEMON
    851     if (pbm->filemon != NULL) {
    852 	while (filemon_process(pbm->filemon) > 0)
    853 	    continue;
    854 	if (filemon_close(pbm->filemon) == -1)
    855 	    error = errno;
    856 	x = filemon_read(pbm->mfp, pbm->mon_fd);
    857 	if (error == 0 && x != 0)
    858 	    error = x;
    859 	pbm->mon_fd = -1;
    860 	pbm->filemon = NULL;
    861 	return error;
    862     }
    863 #endif
    864 
    865     fprintf(pbm->mfp, "\n");	/* ensure end with newline */
    866     return error;
    867 }
    868 
    869 int
    870 meta_job_finish(Job *job)
    871 {
    872     BuildMon *pbm;
    873     int error = 0;
    874     int x;
    875 
    876     if (job != NULL) {
    877 	pbm = &job->bm;
    878     } else {
    879 	pbm = &Mybm;
    880     }
    881     if (pbm->mfp != NULL) {
    882 	error = meta_cmd_finish(pbm);
    883 	x = fclose(pbm->mfp);
    884 	if (error == 0 && x != 0)
    885 	    error = errno;
    886 	pbm->mfp = NULL;
    887 	pbm->meta_fname[0] = '\0';
    888     }
    889     return error;
    890 }
    891 
    892 void
    893 meta_finish(void)
    894 {
    895     Lst_Done(&metaBailiwick);
    896     free(metaBailiwickStr);
    897     Lst_Done(&metaIgnorePaths);
    898     free(metaIgnorePathsStr);
    899 }
    900 
    901 /*
    902  * Fetch a full line from fp - growing bufp if needed
    903  * Return length in bufp.
    904  */
    905 static int
    906 fgetLine(char **bufp, size_t *szp, int o, FILE *fp)
    907 {
    908     char *buf = *bufp;
    909     size_t bufsz = *szp;
    910     struct stat fs;
    911     int x;
    912 
    913     if (fgets(&buf[o], (int)bufsz - o, fp) != NULL) {
    914     check_newline:
    915 	x = o + (int)strlen(&buf[o]);
    916 	if (buf[x - 1] == '\n')
    917 	    return x;
    918 	/*
    919 	 * We need to grow the buffer.
    920 	 * The meta file can give us a clue.
    921 	 */
    922 	if (fstat(fileno(fp), &fs) == 0) {
    923 	    size_t newsz;
    924 	    char *p;
    925 
    926 	    newsz = ROUNDUP(((size_t)fs.st_size / 2), BUFSIZ);
    927 	    if (newsz <= bufsz)
    928 		newsz = ROUNDUP((size_t)fs.st_size, BUFSIZ);
    929 	    if (newsz <= bufsz)
    930 		return x;		/* truncated */
    931 	    DEBUG2(META, "growing buffer %u -> %u\n",
    932 		   (unsigned)bufsz, (unsigned)newsz);
    933 	    p = bmake_realloc(buf, newsz);
    934 	    *bufp = buf = p;
    935 	    *szp = bufsz = newsz;
    936 	    /* fetch the rest */
    937 	    if (fgets(&buf[x], (int)bufsz - x, fp) == NULL)
    938 		return x;		/* truncated! */
    939 	    goto check_newline;
    940 	}
    941     }
    942     return 0;
    943 }
    944 
    945 static bool
    946 prefix_match(const char *prefix, const char *path)
    947 {
    948     size_t n = strlen(prefix);
    949 
    950     return strncmp(path, prefix, n) == 0;
    951 }
    952 
    953 static bool
    954 has_any_prefix(const char *path, StringList *prefixes)
    955 {
    956     StringListNode *ln;
    957 
    958     for (ln = prefixes->first; ln != NULL; ln = ln->next)
    959 	if (prefix_match(ln->datum, path))
    960 	    return true;
    961     return false;
    962 }
    963 
    964 /* See if the path equals prefix or starts with "prefix/". */
    965 static bool
    966 path_starts_with(const char *path, const char *prefix)
    967 {
    968     size_t n = strlen(prefix);
    969 
    970     if (strncmp(path, prefix, n) != 0)
    971 	return false;
    972     return path[n] == '\0' || path[n] == '/';
    973 }
    974 
    975 static bool
    976 meta_ignore(GNode *gn, const char *p)
    977 {
    978     char fname[MAXPATHLEN];
    979 
    980     if (p == NULL)
    981 	return true;
    982 
    983     if (*p == '/') {
    984 	cached_realpath(p, fname); /* clean it up */
    985 	if (has_any_prefix(fname, &metaIgnorePaths)) {
    986 #ifdef DEBUG_META_MODE
    987 	    DEBUG1(META, "meta_oodate: ignoring path: %s\n", p);
    988 #endif
    989 	    return true;
    990 	}
    991     }
    992 
    993     if (metaIgnorePatterns) {
    994 	const char *expr;
    995 	char *pm;
    996 
    997 	/*
    998 	 * XXX: This variable is set on a target GNode but is not one of
    999 	 * the usual local variables.  It should be deleted afterwards.
   1000 	 * Ideally it would not be created in the first place, just like
   1001 	 * in a .for loop.
   1002 	 */
   1003 	Var_Set(gn, ".p.", p);
   1004 	expr = "${" MAKE_META_IGNORE_PATTERNS ":@m@${.p.:M$m}@}";
   1005 	(void)Var_Subst(expr, gn, VARE_WANTRES, &pm);
   1006 	/* TODO: handle errors */
   1007 	if (pm[0] != '\0') {
   1008 #ifdef DEBUG_META_MODE
   1009 	    DEBUG1(META, "meta_oodate: ignoring pattern: %s\n", p);
   1010 #endif
   1011 	    free(pm);
   1012 	    return true;
   1013 	}
   1014 	free(pm);
   1015     }
   1016 
   1017     if (metaIgnoreFilter) {
   1018 	char *fm;
   1019 
   1020 	/* skip if filter result is empty */
   1021 	snprintf(fname, sizeof fname,
   1022 		 "${%s:L:${%s:ts:}}",
   1023 		 p, MAKE_META_IGNORE_FILTER);
   1024 	(void)Var_Subst(fname, gn, VARE_WANTRES, &fm);
   1025 	/* TODO: handle errors */
   1026 	if (*fm == '\0') {
   1027 #ifdef DEBUG_META_MODE
   1028 	    DEBUG1(META, "meta_oodate: ignoring filtered: %s\n", p);
   1029 #endif
   1030 	    free(fm);
   1031 	    return true;
   1032 	}
   1033 	free(fm);
   1034     }
   1035     return false;
   1036 }
   1037 
   1038 /*
   1039  * When running with 'meta' functionality, a target can be out-of-date
   1040  * if any of the references in its meta data file is more recent.
   1041  * We have to track the latestdir on a per-process basis.
   1042  */
   1043 #define LCWD_VNAME_FMT ".meta.%d.lcwd"
   1044 #define LDIR_VNAME_FMT ".meta.%d.ldir"
   1045 
   1046 /*
   1047  * It is possible that a .meta file is corrupted,
   1048  * if we detect this we want to reproduce it.
   1049  * Setting oodate true will have that effect.
   1050  */
   1051 #define CHECK_VALID_META(p) if (!(p != NULL && *p != '\0')) { \
   1052     warnx("%s: %d: malformed", fname, lineno); \
   1053     oodate = true; \
   1054     continue; \
   1055     }
   1056 
   1057 #define DEQUOTE(p) if (*p == '\'') {	\
   1058     char *ep; \
   1059     p++; \
   1060     if ((ep = strchr(p, '\'')) != NULL) \
   1061 	*ep = '\0'; \
   1062     }
   1063 
   1064 static void
   1065 append_if_new(StringList *list, const char *str)
   1066 {
   1067     StringListNode *ln;
   1068 
   1069     for (ln = list->first; ln != NULL; ln = ln->next)
   1070 	if (strcmp(ln->datum, str) == 0)
   1071 	    return;
   1072     Lst_Append(list, bmake_strdup(str));
   1073 }
   1074 
   1075 bool
   1076 meta_oodate(GNode *gn, bool oodate)
   1077 {
   1078     static char *tmpdir = NULL;
   1079     static char cwd[MAXPATHLEN];
   1080     char lcwd_vname[64];
   1081     char ldir_vname[64];
   1082     char lcwd[MAXPATHLEN];
   1083     char latestdir[MAXPATHLEN];
   1084     char fname[MAXPATHLEN];
   1085     char fname1[MAXPATHLEN];
   1086     char fname2[MAXPATHLEN];
   1087     char fname3[MAXPATHLEN];
   1088     FStr dname;
   1089     const char *tname;
   1090     char *p;
   1091     char *link_src;
   1092     char *move_target;
   1093     static size_t cwdlen = 0;
   1094     static size_t tmplen = 0;
   1095     FILE *fp;
   1096     bool needOODATE = false;
   1097     StringList missingFiles;
   1098     bool have_filemon = false;
   1099 
   1100     if (oodate)
   1101 	return oodate;		/* we're done */
   1102 
   1103     dname = Var_Value(gn, ".OBJDIR");
   1104     tname = GNode_VarTarget(gn);
   1105 
   1106     /* if this succeeds fname3 is realpath of dname */
   1107     if (!meta_needed(gn, dname.str, fname3, false))
   1108 	goto oodate_out;
   1109     dname.str = fname3;
   1110 
   1111     Lst_Init(&missingFiles);
   1112 
   1113     /*
   1114      * We need to check if the target is out-of-date. This includes
   1115      * checking if the expanded command has changed. This in turn
   1116      * requires that all variables are set in the same way that they
   1117      * would be if the target needs to be re-built.
   1118      */
   1119     Make_DoAllVar(gn);
   1120 
   1121     meta_name(fname, sizeof fname, dname.str, tname, dname.str);
   1122 
   1123 #ifdef DEBUG_META_MODE
   1124     DEBUG1(META, "meta_oodate: %s\n", fname);
   1125 #endif
   1126 
   1127     if ((fp = fopen(fname, "r")) != NULL) {
   1128 	static char *buf = NULL;
   1129 	static size_t bufsz;
   1130 	int lineno = 0;
   1131 	int lastpid = 0;
   1132 	int pid;
   1133 	int x;
   1134 	StringListNode *cmdNode;
   1135 	struct cached_stat cst;
   1136 
   1137 	if (buf == NULL) {
   1138 	    bufsz = 8 * BUFSIZ;
   1139 	    buf = bmake_malloc(bufsz);
   1140 	}
   1141 
   1142 	if (cwdlen == 0) {
   1143 	    if (getcwd(cwd, sizeof cwd) == NULL)
   1144 		err(1, "Could not get current working directory");
   1145 	    cwdlen = strlen(cwd);
   1146 	}
   1147 	strlcpy(lcwd, cwd, sizeof lcwd);
   1148 	strlcpy(latestdir, cwd, sizeof latestdir);
   1149 
   1150 	if (tmpdir == NULL) {
   1151 	    tmpdir = getTmpdir();
   1152 	    tmplen = strlen(tmpdir);
   1153 	}
   1154 
   1155 	/* we want to track all the .meta we read */
   1156 	Global_Append(".MAKE.META.FILES", fname);
   1157 
   1158 	cmdNode = gn->commands.first;
   1159 	while (!oodate && (x = fgetLine(&buf, &bufsz, 0, fp)) > 0) {
   1160 	    lineno++;
   1161 	    if (buf[x - 1] == '\n')
   1162 		buf[x - 1] = '\0';
   1163 	    else {
   1164 		warnx("%s: %d: line truncated at %u", fname, lineno, x);
   1165 		oodate = true;
   1166 		break;
   1167 	    }
   1168 	    link_src = NULL;
   1169 	    move_target = NULL;
   1170 	    /* Find the start of the build monitor section. */
   1171 	    if (!have_filemon) {
   1172 		if (strncmp(buf, "-- filemon", 10) == 0) {
   1173 		    have_filemon = true;
   1174 		    continue;
   1175 		}
   1176 		if (strncmp(buf, "# buildmon", 10) == 0) {
   1177 		    have_filemon = true;
   1178 		    continue;
   1179 		}
   1180 	    }
   1181 
   1182 	    /* Delimit the record type. */
   1183 	    p = buf;
   1184 #ifdef DEBUG_META_MODE
   1185 	    DEBUG3(META, "%s: %d: %s\n", fname, lineno, buf);
   1186 #endif
   1187 	    strsep(&p, " ");
   1188 	    if (have_filemon) {
   1189 		/*
   1190 		 * We are in the 'filemon' output section.
   1191 		 * Each record from filemon follows the general form:
   1192 		 *
   1193 		 * <key> <pid> <data>
   1194 		 *
   1195 		 * Where:
   1196 		 * <key> is a single letter, denoting the syscall.
   1197 		 * <pid> is the process that made the syscall.
   1198 		 * <data> is the arguments (of interest).
   1199 		 */
   1200 		switch(buf[0]) {
   1201 		case '#':		/* comment */
   1202 		case 'V':		/* version */
   1203 		    break;
   1204 		default:
   1205 		    /*
   1206 		     * We need to track pathnames per-process.
   1207 		     *
   1208 		     * Each process run by make starts off in the 'CWD'
   1209 		     * recorded in the .meta file, if it chdirs ('C')
   1210 		     * elsewhere we need to track that - but only for
   1211 		     * that process.  If it forks ('F'), we initialize
   1212 		     * the child to have the same cwd as its parent.
   1213 		     *
   1214 		     * We also need to track the 'latestdir' of
   1215 		     * interest.  This is usually the same as cwd, but
   1216 		     * not if a process is reading directories.
   1217 		     *
   1218 		     * Each time we spot a different process ('pid')
   1219 		     * we save the current value of 'latestdir' in a
   1220 		     * variable qualified by 'lastpid', and
   1221 		     * re-initialize 'latestdir' to any pre-saved
   1222 		     * value for the current 'pid' and 'CWD' if none.
   1223 		     */
   1224 		    CHECK_VALID_META(p);
   1225 		    pid = atoi(p);
   1226 		    if (pid > 0 && pid != lastpid) {
   1227 			FStr ldir;
   1228 
   1229 			if (lastpid > 0) {
   1230 			    /* We need to remember these. */
   1231 			    Global_SetExpand(lcwd_vname, lcwd);
   1232 			    Global_SetExpand(ldir_vname, latestdir);
   1233 			}
   1234 			snprintf(lcwd_vname, sizeof lcwd_vname, LCWD_VNAME_FMT, pid);
   1235 			snprintf(ldir_vname, sizeof ldir_vname, LDIR_VNAME_FMT, pid);
   1236 			lastpid = pid;
   1237 			ldir = Var_Value(SCOPE_GLOBAL, ldir_vname);
   1238 			if (ldir.str != NULL) {
   1239 			    strlcpy(latestdir, ldir.str, sizeof latestdir);
   1240 			    FStr_Done(&ldir);
   1241 			}
   1242 			ldir = Var_Value(SCOPE_GLOBAL, lcwd_vname);
   1243 			if (ldir.str != NULL) {
   1244 			    strlcpy(lcwd, ldir.str, sizeof lcwd);
   1245 			    FStr_Done(&ldir);
   1246 			}
   1247 		    }
   1248 		    /* Skip past the pid. */
   1249 		    if (strsep(&p, " ") == NULL)
   1250 			continue;
   1251 #ifdef DEBUG_META_MODE
   1252 		    if (DEBUG(META))
   1253 			debug_printf("%s: %d: %d: %c: cwd=%s lcwd=%s ldir=%s\n",
   1254 				     fname, lineno,
   1255 				     pid, buf[0], cwd, lcwd, latestdir);
   1256 #endif
   1257 		    break;
   1258 		}
   1259 
   1260 		CHECK_VALID_META(p);
   1261 
   1262 		/* Process according to record type. */
   1263 		switch (buf[0]) {
   1264 		case 'X':		/* eXit */
   1265 		    Var_DeleteExpand(SCOPE_GLOBAL, lcwd_vname);
   1266 		    Var_DeleteExpand(SCOPE_GLOBAL, ldir_vname);
   1267 		    lastpid = 0;	/* no need to save ldir_vname */
   1268 		    break;
   1269 
   1270 		case 'F':		/* [v]Fork */
   1271 		    {
   1272 			char cldir[64];
   1273 			int child;
   1274 
   1275 			child = atoi(p);
   1276 			if (child > 0) {
   1277 			    snprintf(cldir, sizeof cldir, LCWD_VNAME_FMT, child);
   1278 			    Global_SetExpand(cldir, lcwd);
   1279 			    snprintf(cldir, sizeof cldir, LDIR_VNAME_FMT, child);
   1280 			    Global_SetExpand(cldir, latestdir);
   1281 #ifdef DEBUG_META_MODE
   1282 			    if (DEBUG(META))
   1283 				debug_printf(
   1284 					"%s: %d: %d: cwd=%s lcwd=%s ldir=%s\n",
   1285 					fname, lineno,
   1286 					child, cwd, lcwd, latestdir);
   1287 #endif
   1288 			}
   1289 		    }
   1290 		    break;
   1291 
   1292 		case 'C':		/* Chdir */
   1293 		    /* Update lcwd and latest directory. */
   1294 		    strlcpy(latestdir, p, sizeof latestdir);
   1295 		    strlcpy(lcwd, p, sizeof lcwd);
   1296 		    Global_SetExpand(lcwd_vname, lcwd);
   1297 		    Global_SetExpand(ldir_vname, lcwd);
   1298 #ifdef DEBUG_META_MODE
   1299 		    DEBUG4(META, "%s: %d: cwd=%s ldir=%s\n",
   1300 			   fname, lineno, cwd, lcwd);
   1301 #endif
   1302 		    break;
   1303 
   1304 		case 'M':		/* renaMe */
   1305 		    /*
   1306 		     * For 'M'oves we want to check
   1307 		     * the src as for 'R'ead
   1308 		     * and the target as for 'W'rite.
   1309 		     */
   1310 		    {
   1311 			char *cp = p;	/* save this for a second */
   1312 			/* now get target */
   1313 			if (strsep(&p, " ") == NULL)
   1314 			    continue;
   1315 			CHECK_VALID_META(p);
   1316 			move_target = p;
   1317 			p = cp;
   1318 		    }
   1319 		    /* 'L' and 'M' put single quotes around the args */
   1320 		    DEQUOTE(p);
   1321 		    DEQUOTE(move_target);
   1322 		    /* FALLTHROUGH */
   1323 		case 'D':		/* unlink */
   1324 		    if (*p == '/') {
   1325 			/* remove any missingFiles entries that match p */
   1326 			StringListNode *ln = missingFiles.first;
   1327 			while (ln != NULL) {
   1328 			    StringListNode *next = ln->next;
   1329 			    if (path_starts_with(ln->datum, p)) {
   1330 				free(ln->datum);
   1331 				Lst_Remove(&missingFiles, ln);
   1332 			    }
   1333 			    ln = next;
   1334 			}
   1335 		    }
   1336 		    if (buf[0] == 'M') {
   1337 			/* the target of the mv is a file 'W'ritten */
   1338 #ifdef DEBUG_META_MODE
   1339 			DEBUG2(META, "meta_oodate: M %s -> %s\n",
   1340 			       p, move_target);
   1341 #endif
   1342 			p = move_target;
   1343 			goto check_write;
   1344 		    }
   1345 		    break;
   1346 		case 'L':		/* Link */
   1347 		    /*
   1348 		     * For 'L'inks check
   1349 		     * the src as for 'R'ead
   1350 		     * and the target as for 'W'rite.
   1351 		     */
   1352 		    link_src = p;
   1353 		    /* now get target */
   1354 		    if (strsep(&p, " ") == NULL)
   1355 			continue;
   1356 		    CHECK_VALID_META(p);
   1357 		    /* 'L' and 'M' put single quotes around the args */
   1358 		    DEQUOTE(p);
   1359 		    DEQUOTE(link_src);
   1360 #ifdef DEBUG_META_MODE
   1361 		    DEBUG2(META, "meta_oodate: L %s -> %s\n", link_src, p);
   1362 #endif
   1363 		    /* FALLTHROUGH */
   1364 		case 'W':		/* Write */
   1365 		check_write:
   1366 		    /*
   1367 		     * If a file we generated within our bailiwick
   1368 		     * but outside of .OBJDIR is missing,
   1369 		     * we need to do it again.
   1370 		     */
   1371 		    /* ignore non-absolute paths */
   1372 		    if (*p != '/')
   1373 			break;
   1374 
   1375 		    if (Lst_IsEmpty(&metaBailiwick))
   1376 			break;
   1377 
   1378 		    /* ignore cwd - normal dependencies handle those */
   1379 		    if (strncmp(p, cwd, cwdlen) == 0)
   1380 			break;
   1381 
   1382 		    if (!has_any_prefix(p, &metaBailiwick))
   1383 			break;
   1384 
   1385 		    /* tmpdir might be within */
   1386 		    if (tmplen > 0 && strncmp(p, tmpdir, tmplen) == 0)
   1387 			break;
   1388 
   1389 		    /* ignore anything containing the string "tmp" */
   1390 		    /* XXX: The arguments to strstr must be swapped. */
   1391 		    if (strstr("tmp", p) != NULL)
   1392 			break;
   1393 
   1394 		    if ((link_src != NULL && cached_lstat(p, &cst) < 0) ||
   1395 			(link_src == NULL && cached_stat(p, &cst) < 0)) {
   1396 			if (!meta_ignore(gn, p))
   1397 			    append_if_new(&missingFiles, p);
   1398 		    }
   1399 		    break;
   1400 		check_link_src:
   1401 		    p = link_src;
   1402 		    link_src = NULL;
   1403 #ifdef DEBUG_META_MODE
   1404 		    DEBUG1(META, "meta_oodate: L src %s\n", p);
   1405 #endif
   1406 		    /* FALLTHROUGH */
   1407 		case 'R':		/* Read */
   1408 		case 'E':		/* Exec */
   1409 		    /*
   1410 		     * Check for runtime files that can't
   1411 		     * be part of the dependencies because
   1412 		     * they are _expected_ to change.
   1413 		     */
   1414 		    if (meta_ignore(gn, p))
   1415 			break;
   1416 
   1417 		    /*
   1418 		     * The rest of the record is the file name.
   1419 		     * Check if it's not an absolute path.
   1420 		     */
   1421 		    {
   1422 			char *sdirs[4];
   1423 			char **sdp;
   1424 			int sdx = 0;
   1425 			bool found = false;
   1426 
   1427 			if (*p == '/') {
   1428 			    sdirs[sdx++] = p; /* done */
   1429 			} else {
   1430 			    if (strcmp(".", p) == 0)
   1431 				continue; /* no point */
   1432 
   1433 			    /* Check vs latestdir */
   1434 			    snprintf(fname1, sizeof fname1, "%s/%s", latestdir, p);
   1435 			    sdirs[sdx++] = fname1;
   1436 
   1437 			    if (strcmp(latestdir, lcwd) != 0) {
   1438 				/* Check vs lcwd */
   1439 				snprintf(fname2, sizeof fname2, "%s/%s", lcwd, p);
   1440 				sdirs[sdx++] = fname2;
   1441 			    }
   1442 			    if (strcmp(lcwd, cwd) != 0) {
   1443 				/* Check vs cwd */
   1444 				snprintf(fname3, sizeof fname3, "%s/%s", cwd, p);
   1445 				sdirs[sdx++] = fname3;
   1446 			    }
   1447 			}
   1448 			sdirs[sdx++] = NULL;
   1449 
   1450 			for (sdp = sdirs; *sdp != NULL && !found; sdp++) {
   1451 #ifdef DEBUG_META_MODE
   1452 			    DEBUG3(META, "%s: %d: looking for: %s\n",
   1453 				   fname, lineno, *sdp);
   1454 #endif
   1455 			    if (cached_stat(*sdp, &cst) == 0) {
   1456 				found = true;
   1457 				p = *sdp;
   1458 			    }
   1459 			}
   1460 			if (found) {
   1461 #ifdef DEBUG_META_MODE
   1462 			    DEBUG3(META, "%s: %d: found: %s\n",
   1463 				   fname, lineno, p);
   1464 #endif
   1465 			    if (!S_ISDIR(cst.cst_mode) &&
   1466 				cst.cst_mtime > gn->mtime) {
   1467 				DEBUG3(META, "%s: %d: file '%s' is newer than the target...\n",
   1468 				       fname, lineno, p);
   1469 				oodate = true;
   1470 			    } else if (S_ISDIR(cst.cst_mode)) {
   1471 				/* Update the latest directory. */
   1472 				cached_realpath(p, latestdir);
   1473 			    }
   1474 			} else if (errno == ENOENT && *p == '/' &&
   1475 				   strncmp(p, cwd, cwdlen) != 0) {
   1476 			    /*
   1477 			     * A referenced file outside of CWD is missing.
   1478 			     * We cannot catch every eventuality here...
   1479 			     */
   1480 			    append_if_new(&missingFiles, p);
   1481 			}
   1482 		    }
   1483 		    if (buf[0] == 'E') {
   1484 			/* previous latestdir is no longer relevant */
   1485 			strlcpy(latestdir, lcwd, sizeof latestdir);
   1486 		    }
   1487 		    break;
   1488 		default:
   1489 		    break;
   1490 		}
   1491 		if (!oodate && buf[0] == 'L' && link_src != NULL)
   1492 		    goto check_link_src;
   1493 	    } else if (strcmp(buf, "CMD") == 0) {
   1494 		/*
   1495 		 * Compare the current command with the one in the
   1496 		 * meta data file.
   1497 		 */
   1498 		if (cmdNode == NULL) {
   1499 		    DEBUG2(META, "%s: %d: there were more build commands in the meta data file than there are now...\n",
   1500 			   fname, lineno);
   1501 		    oodate = true;
   1502 		} else {
   1503 		    const char *cp;
   1504 		    char *cmd = cmdNode->datum;
   1505 		    bool hasOODATE = false;
   1506 
   1507 		    if (strstr(cmd, "$?") != NULL)
   1508 			hasOODATE = true;
   1509 		    else if ((cp = strstr(cmd, ".OODATE")) != NULL) {
   1510 			/* check for $[{(].OODATE[:)}] */
   1511 			if (cp > cmd + 2 && cp[-2] == '$')
   1512 			    hasOODATE = true;
   1513 		    }
   1514 		    if (hasOODATE) {
   1515 			needOODATE = true;
   1516 			DEBUG2(META, "%s: %d: cannot compare command using .OODATE\n",
   1517 			       fname, lineno);
   1518 		    }
   1519 		    (void)Var_Subst(cmd, gn, VARE_UNDEFERR, &cmd);
   1520 		    /* TODO: handle errors */
   1521 
   1522 		    if ((cp = strchr(cmd, '\n')) != NULL) {
   1523 			int n;
   1524 
   1525 			/*
   1526 			 * This command contains newlines, we need to
   1527 			 * fetch more from the .meta file before we
   1528 			 * attempt a comparison.
   1529 			 */
   1530 			/* first put the newline back at buf[x - 1] */
   1531 			buf[x - 1] = '\n';
   1532 			do {
   1533 			    /* now fetch the next line */
   1534 			    if ((n = fgetLine(&buf, &bufsz, x, fp)) <= 0)
   1535 				break;
   1536 			    x = n;
   1537 			    lineno++;
   1538 			    if (buf[x - 1] != '\n') {
   1539 				warnx("%s: %d: line truncated at %u", fname, lineno, x);
   1540 				break;
   1541 			    }
   1542 			    cp = strchr(cp + 1, '\n');
   1543 			} while (cp != NULL);
   1544 			if (buf[x - 1] == '\n')
   1545 			    buf[x - 1] = '\0';
   1546 		    }
   1547 		    if (p != NULL &&
   1548 			!hasOODATE &&
   1549 			!(gn->type & OP_NOMETA_CMP) &&
   1550 			(strcmp(p, cmd) != 0)) {
   1551 			DEBUG4(META, "%s: %d: a build command has changed\n%s\nvs\n%s\n",
   1552 			       fname, lineno, p, cmd);
   1553 			if (!metaIgnoreCMDs)
   1554 			    oodate = true;
   1555 		    }
   1556 		    free(cmd);
   1557 		    cmdNode = cmdNode->next;
   1558 		}
   1559 	    } else if (strcmp(buf, "CWD") == 0) {
   1560 		/*
   1561 		 * Check if there are extra commands now
   1562 		 * that weren't in the meta data file.
   1563 		 */
   1564 		if (!oodate && cmdNode != NULL) {
   1565 		    DEBUG2(META, "%s: %d: there are extra build commands now that weren't in the meta data file\n",
   1566 			   fname, lineno);
   1567 		    oodate = true;
   1568 		}
   1569 		CHECK_VALID_META(p);
   1570 		if (strcmp(p, cwd) != 0) {
   1571 		    DEBUG4(META, "%s: %d: the current working directory has changed from '%s' to '%s'\n",
   1572 			   fname, lineno, p, curdir);
   1573 		    oodate = true;
   1574 		}
   1575 	    }
   1576 	}
   1577 
   1578 	fclose(fp);
   1579 	if (!Lst_IsEmpty(&missingFiles)) {
   1580 	    DEBUG2(META, "%s: missing files: %s...\n",
   1581 		   fname, (char *)missingFiles.first->datum);
   1582 	    oodate = true;
   1583 	}
   1584 	if (!oodate && !have_filemon && filemonMissing) {
   1585 	    DEBUG1(META, "%s: missing filemon data\n", fname);
   1586 	    oodate = true;
   1587 	}
   1588     } else {
   1589 	if (writeMeta && (metaMissing || (gn->type & OP_META))) {
   1590 	    const char *cp = NULL;
   1591 
   1592 	    /* if target is in .CURDIR we do not need a meta file */
   1593 	    if (gn->path != NULL && (cp = strrchr(gn->path, '/')) != NULL &&
   1594 		(cp > gn->path)) {
   1595 		if (strncmp(curdir, gn->path, (size_t)(cp - gn->path)) != 0) {
   1596 		    cp = NULL;		/* not in .CURDIR */
   1597 		}
   1598 	    }
   1599 	    if (cp == NULL) {
   1600 		DEBUG1(META, "%s: required but missing\n", fname);
   1601 		oodate = true;
   1602 		needOODATE = true;	/* assume the worst */
   1603 	    }
   1604 	}
   1605     }
   1606 
   1607     Lst_DoneCall(&missingFiles, free);
   1608 
   1609     if (oodate && needOODATE) {
   1610 	/*
   1611 	 * Target uses .OODATE which is empty; or we wouldn't be here.
   1612 	 * We have decided it is oodate, so .OODATE needs to be set.
   1613 	 * All we can sanely do is set it to .ALLSRC.
   1614 	 */
   1615 	Var_Delete(gn, OODATE);
   1616 	Var_Set(gn, OODATE, GNode_VarAllsrc(gn));
   1617     }
   1618 
   1619  oodate_out:
   1620     FStr_Done(&dname);
   1621     return oodate;
   1622 }
   1623 
   1624 /* support for compat mode */
   1625 
   1626 static int childPipe[2];
   1627 
   1628 void
   1629 meta_compat_start(void)
   1630 {
   1631 #ifdef USE_FILEMON_ONCE
   1632     /*
   1633      * We need to re-open filemon for each cmd.
   1634      */
   1635     BuildMon *pbm = &Mybm;
   1636 
   1637     if (pbm->mfp != NULL && useFilemon) {
   1638 	meta_open_filemon(pbm);
   1639     } else {
   1640 	pbm->mon_fd = -1;
   1641 	pbm->filemon = NULL;
   1642     }
   1643 #endif
   1644     if (pipe(childPipe) < 0)
   1645 	Punt("Cannot create pipe: %s", strerror(errno));
   1646     /* Set close-on-exec flag for both */
   1647     (void)fcntl(childPipe[0], F_SETFD, FD_CLOEXEC);
   1648     (void)fcntl(childPipe[1], F_SETFD, FD_CLOEXEC);
   1649 }
   1650 
   1651 void
   1652 meta_compat_child(void)
   1653 {
   1654     meta_job_child(NULL);
   1655     if (dup2(childPipe[1], 1) < 0 || dup2(1, 2) < 0)
   1656 	execDie("dup2", "pipe");
   1657 }
   1658 
   1659 void
   1660 meta_compat_parent(pid_t child)
   1661 {
   1662     int outfd, metafd, maxfd, nfds;
   1663     char buf[BUFSIZ+1];
   1664     fd_set readfds;
   1665 
   1666     meta_job_parent(NULL, child);
   1667     close(childPipe[1]);			/* child side */
   1668     outfd = childPipe[0];
   1669 #ifdef USE_FILEMON
   1670     metafd = Mybm.filemon != NULL ? filemon_readfd(Mybm.filemon) : -1;
   1671 #else
   1672     metafd = -1;
   1673 #endif
   1674     maxfd = -1;
   1675     if (outfd > maxfd)
   1676 	    maxfd = outfd;
   1677     if (metafd > maxfd)
   1678 	    maxfd = metafd;
   1679 
   1680     while (outfd != -1 || metafd != -1) {
   1681 	FD_ZERO(&readfds);
   1682 	if (outfd != -1) {
   1683 	    FD_SET(outfd, &readfds);
   1684 	}
   1685 	if (metafd != -1) {
   1686 	    FD_SET(metafd, &readfds);
   1687 	}
   1688 	nfds = select(maxfd + 1, &readfds, NULL, NULL, NULL);
   1689 	if (nfds == -1) {
   1690 	    if (errno == EINTR)
   1691 		continue;
   1692 	    err(1, "select");
   1693 	}
   1694 
   1695 	if (outfd != -1 && FD_ISSET(outfd, &readfds) != 0) do {
   1696 	    /* XXX this is not line-buffered */
   1697 	    ssize_t nread = read(outfd, buf, sizeof buf - 1);
   1698 	    if (nread == -1)
   1699 		err(1, "read");
   1700 	    if (nread == 0) {
   1701 		close(outfd);
   1702 		outfd = -1;
   1703 		break;
   1704 	    }
   1705 	    fwrite(buf, 1, (size_t)nread, stdout);
   1706 	    fflush(stdout);
   1707 	    buf[nread] = '\0';
   1708 	    meta_job_output(NULL, buf, "");
   1709 	} while (/*CONSTCOND*/false);
   1710 	if (metafd != -1 && FD_ISSET(metafd, &readfds) != 0) {
   1711 	    if (meta_job_event(NULL) <= 0)
   1712 		metafd = -1;
   1713 	}
   1714     }
   1715 }
   1716 
   1717 #endif /* USE_META */
   1718