bin/bmake/meta.c

   1 /*      $NetBSD: meta.c,v 1.61 2016/06/07 00:40:00 sjg Exp $ */
   2
   3 /*
   4  * Implement 'meta' mode.
   5  * Adapted from John Birrell's patches to FreeBSD make.
   6  * --sjg
   7  */
   8 /*
   9  * Copyright (c) 2009-2016, 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 <sys/ioctl.h>
  40 #ifdef HAVE_LIBGEN_H
  41 #include <libgen.h>
  42 #elif !defined(HAVE_DIRNAME)
  43 char * dirname(char *);
  44 #endif
  45 #include <errno.h>
  46 #if !defined(HAVE_CONFIG_H) || defined(HAVE_ERR_H)
  47 #include <err.h>
  48 #endif
  49
  50 #include "make.h"
  51 #include "job.h"
  52
  53 #ifdef HAVE_FILEMON_H
  54 # include <filemon.h>
  55 #endif
  56 #if !defined(USE_FILEMON) && defined(FILEMON_SET_FD)
  57 # define USE_FILEMON
  58 #endif
  59
  60 static BuildMon Mybm;                   /* for compat */
  61 static Lst metaBailiwick;               /* our scope of control */
  62 static char *metaBailiwickStr;          /* string storage for the list */
  63 static Lst metaIgnorePaths;             /* paths we deliberately ignore */
  64 static char *metaIgnorePathsStr;        /* string storage for the list */
  65
  66 #ifndef MAKE_META_IGNORE_PATHS
  67 #define MAKE_META_IGNORE_PATHS ".MAKE.META.IGNORE_PATHS"
  68 #endif
  69 #ifndef MAKE_META_IGNORE_PATTERNS
  70 #define MAKE_META_IGNORE_PATTERNS ".MAKE.META.IGNORE_PATTERNS"
  71 #endif
  72
  73 Boolean useMeta = FALSE;
  74 static Boolean useFilemon = FALSE;
  75 static Boolean writeMeta = FALSE;
  76 static Boolean metaMissing = FALSE;     /* oodate if missing */
  77 static Boolean filemonMissing = FALSE;  /* oodate if missing */
  78 static Boolean metaEnv = FALSE;         /* don't save env unless asked */
  79 static Boolean metaVerbose = FALSE;
  80 static Boolean metaIgnoreCMDs = FALSE;  /* ignore CMDs in .meta files */
  81 static Boolean metaIgnorePatterns = FALSE; /* do we need to do pattern matches */
  82 static Boolean metaCurdirOk = FALSE;    /* write .meta in .CURDIR Ok? */
  83 static Boolean metaSilent = FALSE;      /* if we have a .meta be SILENT */
  84
  85 extern Boolean forceJobs;
  86 extern Boolean comatMake;
  87 extern char    **environ;
  88
  89 #define MAKE_META_PREFIX        ".MAKE.META.PREFIX"
  90
  91 #ifndef N2U
  92 # define N2U(n, u)   (((n) + ((u) - 1)) / (u))
  93 #endif
  94 #ifndef ROUNDUP
  95 # define ROUNDUP(n, u)   (N2U((n), (u)) * (u))
  96 #endif
  97
  98 #if !defined(HAVE_STRSEP)
  99 # define strsep(s, d) stresep((s), (d), 0)
 100 #endif
 101
 102 /*
 103  * Filemon is a kernel module which snoops certain syscalls.
 104  *
 105  * C chdir
 106  * E exec
 107  * F [v]fork
 108  * L [sym]link
 109  * M rename
 110  * R read
 111  * W write
 112  * S stat
 113  *
 114  * See meta_oodate below - we mainly care about 'E' and 'R'.
 115  *
 116  * We can still use meta mode without filemon, but
 117  * the benefits are more limited.
 118  */
 119 #ifdef USE_FILEMON
 120 # ifndef _PATH_FILEMON
 121 #   define _PATH_FILEMON "/dev/filemon"
 122 # endif
 123
 124 /*
 125  * Open the filemon device.
 126  */
 127 static void
 128 filemon_open(BuildMon *pbm)
 129 {
 130     int retry;
 131
 132     pbm->mon_fd = pbm->filemon_fd = -1;
 133     if (!useFilemon)
 134         return;
 135
 136     for (retry = 5; retry >= 0; retry--) {
 137         if ((pbm->filemon_fd = open(_PATH_FILEMON, O_RDWR)) >= 0)
 138             break;
 139     }
 140
 141     if (pbm->filemon_fd < 0) {
 142         useFilemon = FALSE;
 143         warn("Could not open %s", _PATH_FILEMON);
 144         return;
 145     }
 146
 147     /*
 148      * We use a file outside of '.'
 149      * to avoid a FreeBSD kernel bug where unlink invalidates
 150      * cwd causing getcwd to do a lot more work.
 151      * We only care about the descriptor.
 152      */
 153     pbm->mon_fd = mkTempFile("filemon.XXXXXX", NULL);
 154     if (ioctl(pbm->filemon_fd, FILEMON_SET_FD, &pbm->mon_fd) < 0) {
 155         err(1, "Could not set filemon file descriptor!");
 156     }
 157     /* we don't need these once we exec */
 158     (void)fcntl(pbm->mon_fd, F_SETFD, FD_CLOEXEC);
 159     (void)fcntl(pbm->filemon_fd, F_SETFD, FD_CLOEXEC);
 160 }
 161
 162 /*
 163  * Read the build monitor output file and write records to the target's
 164  * metadata file.
 165  */
 166 static int
 167 filemon_read(FILE *mfp, int fd)
 168 {
 169     char buf[BUFSIZ];
 170     int n;
 171     int error;
 172
 173     /* Check if we're not writing to a meta data file.*/
 174     if (mfp == NULL) {
 175         if (fd >= 0)
 176             close(fd);                  /* not interested */
 177         return 0;
 178     }
 179     /* rewind */
 180     (void)lseek(fd, (off_t)0, SEEK_SET);
 181
 182     error = 0;
 183     fprintf(mfp, "\n-- filemon acquired metadata --\n");
 184
 185     while ((n = read(fd, buf, sizeof(buf))) > 0) {
 186         if ((int)fwrite(buf, 1, n, mfp) < n)
 187             error = EIO;
 188     }
 189     fflush(mfp);
 190     if (close(fd) < 0)
 191         error = errno;
 192     return error;
 193 }
 194 #endif
 195
 196 /*
 197  * when realpath() fails,
 198  * we use this, to clean up ./ and ../
 199  */
 200 static void
 201 eat_dots(char *buf, size_t bufsz, int dots)
 202 {
 203     char *cp;
 204     char *cp2;
 205     const char *eat;
 206     size_t eatlen;
 207
 208     switch (dots) {
 209     case 1:
 210         eat = "/./";
 211         eatlen = 2;
 212         break;
 213     case 2:
 214         eat = "/../";
 215         eatlen = 3;
 216         break;
 217     default:
 218         return;
 219     }
 220
 221     do {
 222         cp = strstr(buf, eat);
 223         if (cp) {
 224             cp2 = cp + eatlen;
 225             if (dots == 2 && cp > buf) {
 226                 do {
 227                     cp--;
 228                 } while (cp > buf && *cp != '/');
 229             }
 230             if (*cp == '/') {
 231                 strlcpy(cp, cp2, bufsz - (cp - buf));
 232             } else {
 233                 return;                 /* can't happen? */
 234             }
 235         }
 236     } while (cp);
 237 }
 238
 239 static char *
 240 meta_name(struct GNode *gn, char *mname, size_t mnamelen,
 241           const char *dname,
 242           const char *tname,
 243           const char *cwd)
 244 {
 245     char buf[MAXPATHLEN];
 246     char *rp;
 247     char *cp;
 248     char *tp;
 249
 250     /*
 251      * Weed out relative paths from the target file name.
 252      * We have to be careful though since if target is a
 253      * symlink, the result will be unstable.
 254      * So we use realpath() just to get the dirname, and leave the
 255      * basename as given to us.
 256      */
 257     if ((cp = strrchr(tname, '/'))) {
 258         if (cached_realpath(tname, buf)) {
 259             if ((rp = strrchr(buf, '/'))) {
 260                 rp++;
 261                 cp++;
 262                 if (strcmp(cp, rp) != 0)
 263                     strlcpy(rp, cp, sizeof(buf) - (rp - buf));
 264             }
 265             tname = buf;
 266         } else {
 267             /*
 268              * We likely have a directory which is about to be made.
 269              * We pretend realpath() succeeded, to have a chance
 270              * of generating the same meta file name that we will
 271              * next time through.
 272              */
 273             if (tname[0] == '/') {
 274                 strlcpy(buf, tname, sizeof(buf));
 275             } else {
 276                 snprintf(buf, sizeof(buf), "%s/%s", cwd, tname);
 277             }
 278             eat_dots(buf, sizeof(buf), 1);      /* ./ */
 279             eat_dots(buf, sizeof(buf), 2);      /* ../ */
 280             tname = buf;
 281         }
 282     }
 283     /* on some systems dirname may modify its arg */
 284     tp = bmake_strdup(tname);
 285     if (strcmp(dname, dirname(tp)) == 0)
 286         snprintf(mname, mnamelen, "%s.meta", tname);
 287     else {
 288         snprintf(mname, mnamelen, "%s/%s.meta", dname, tname);
 289
 290         /*
 291          * Replace path separators in the file name after the
 292          * current object directory path.
 293          */
 294         cp = mname + strlen(dname) + 1;
 295
 296         while (*cp != '\0') {
 297             if (*cp == '/')
 298                 *cp = '_';
 299             cp++;
 300         }
 301     }
 302     free(tp);
 303     return (mname);
 304 }
 305
 306 /*
 307  * Return true if running ${.MAKE}
 308  * Bypassed if target is flagged .MAKE
 309  */
 310 static int
 311 is_submake(void *cmdp, void *gnp)
 312 {
 313     static char *p_make = NULL;
 314     static int p_len;
 315     char  *cmd = cmdp;
 316     GNode *gn = gnp;
 317     char *mp = NULL;
 318     char *cp;
 319     char *cp2;
 320     int rc = 0;                         /* keep looking */
 321
 322     if (!p_make) {
 323         p_make = Var_Value(".MAKE", gn, &cp);
 324         p_len = strlen(p_make);
 325     }
 326     cp = strchr(cmd, '$');
 327     if ((cp)) {
 328         mp = Var_Subst(NULL, cmd, gn, VARF_WANTRES);
 329         cmd = mp;
 330     }
 331     cp2 = strstr(cmd, p_make);
 332     if ((cp2)) {
 333         switch (cp2[p_len]) {
 334         case '\0':
 335         case ' ':
 336         case '\t':
 337         case '\n':
 338             rc = 1;
 339             break;
 340         }
 341         if (cp2 > cmd && rc > 0) {
 342             switch (cp2[-1]) {
 343             case ' ':
 344             case '\t':
 345             case '\n':
 346                 break;
 347             default:
 348                 rc = 0;                 /* no match */
 349                 break;
 350             }
 351         }
 352     }
 353     free(mp);
 354     return (rc);
 355 }
 356
 357 typedef struct meta_file_s {
 358     FILE *fp;
 359     GNode *gn;
 360 } meta_file_t;
 361
 362 static int
 363 printCMD(void *cmdp, void *mfpp)
 364 {
 365     meta_file_t *mfp = mfpp;
 366     char *cmd = cmdp;
 367     char *cp = NULL;
 368
 369     if (strchr(cmd, '$')) {
 370         cmd = cp = Var_Subst(NULL, cmd, mfp->gn, VARF_WANTRES);
 371     }
 372     fprintf(mfp->fp, "CMD %s\n", cmd);
 373     free(cp);
 374     return 0;
 375 }
 376
 377 /*
 378  * Certain node types never get a .meta file
 379  */
 380 #define SKIP_META_TYPE(_type) do { \
 381     if ((gn->type & __CONCAT(OP_, _type))) {    \
 382         if (verbose) { \
 383             fprintf(debug_file, "Skipping meta for %s: .%s\n", \
 384                     gn->name, __STRING(_type));                \
 385         } \
 386         return FALSE; \
 387     } \
 388 } while (0)
 389
 390
 391 /*
 392  * Do we need/want a .meta file ?
 393  */
 394 static Boolean
 395 meta_needed(GNode *gn, const char *dname, const char *tname,
 396              char *objdir, int verbose)
 397 {
 398     struct stat fs;
 399
 400     if (verbose)
 401         verbose = DEBUG(META);
 402
 403     /* This may be a phony node which we don't want meta data for... */
 404     /* Skip .meta for .BEGIN, .END, .ERROR etc as well. */
 405     /* Or it may be explicitly flagged as .NOMETA */
 406     SKIP_META_TYPE(NOMETA);
 407     /* Unless it is explicitly flagged as .META */
 408     if (!(gn->type & OP_META)) {
 409         SKIP_META_TYPE(PHONY);
 410         SKIP_META_TYPE(SPECIAL);
 411         SKIP_META_TYPE(MAKE);
 412     }
 413
 414     /* Check if there are no commands to execute. */
 415     if (Lst_IsEmpty(gn->commands)) {
 416         if (verbose)
 417             fprintf(debug_file, "Skipping meta for %s: no commands\n",
 418                     gn->name);
 419         return FALSE;
 420     }
 421     if ((gn->type & (OP_META|OP_SUBMAKE)) == OP_SUBMAKE) {
 422         /* OP_SUBMAKE is a bit too aggressive */
 423         if (Lst_ForEach(gn->commands, is_submake, gn)) {
 424             if (DEBUG(META))
 425                 fprintf(debug_file, "Skipping meta for %s: .SUBMAKE\n",
 426                         gn->name);
 427             return FALSE;
 428         }
 429     }
 430
 431     /* The object directory may not exist. Check it.. */
 432     if (cached_stat(dname, &fs) != 0) {
 433         if (verbose)
 434             fprintf(debug_file, "Skipping meta for %s: no .OBJDIR\n",
 435                     gn->name);
 436         return FALSE;
 437     }
 438
 439     /* make sure these are canonical */
 440     if (cached_realpath(dname, objdir))
 441         dname = objdir;
 442
 443     /* If we aren't in the object directory, don't create a meta file. */
 444     if (!metaCurdirOk && strcmp(curdir, dname) == 0) {
 445         if (verbose)
 446             fprintf(debug_file, "Skipping meta for %s: .OBJDIR == .CURDIR\n",
 447                     gn->name);
 448         return FALSE;
 449     }
 450     return TRUE;
 451 }
 452
 453
 454 static FILE *
 455 meta_create(BuildMon *pbm, GNode *gn)
 456 {
 457     meta_file_t mf;
 458     char buf[MAXPATHLEN];
 459     char objdir[MAXPATHLEN];
 460     char **ptr;
 461     const char *dname;
 462     const char *tname;
 463     char *fname;
 464     const char *cp;
 465     char *p[4];                         /* >= possible uses */
 466     int i;
 467
 468     mf.fp = NULL;
 469     i = 0;
 470
 471     dname = Var_Value(".OBJDIR", gn, &p[i++]);
 472     tname = Var_Value(TARGET, gn, &p[i++]);
 473
 474     /* if this succeeds objdir is realpath of dname */
 475     if (!meta_needed(gn, dname, tname, objdir, TRUE))
 476         goto out;
 477     dname = objdir;
 478
 479     if (metaVerbose) {
 480         char *mp;
 481
 482         /* Describe the target we are building */
 483         mp = Var_Subst(NULL, "${" MAKE_META_PREFIX "}", gn, VARF_WANTRES);
 484         if (*mp)
 485             fprintf(stdout, "%s\n", mp);
 486         free(mp);
 487     }
 488     /* Get the basename of the target */
 489     if ((cp = strrchr(tname, '/')) == NULL) {
 490         cp = tname;
 491     } else {
 492         cp++;
 493     }
 494
 495     fflush(stdout);
 496
 497     if (!writeMeta)
 498         /* Don't create meta data. */
 499         goto out;
 500
 501     fname = meta_name(gn, pbm->meta_fname, sizeof(pbm->meta_fname),
 502                       dname, tname, objdir);
 503
 504 #ifdef DEBUG_META_MODE
 505     if (DEBUG(META))
 506         fprintf(debug_file, "meta_create: %s\n", fname);
 507 #endif
 508
 509     if ((mf.fp = fopen(fname, "w")) == NULL)
 510         err(1, "Could not open meta file '%s'", fname);
 511
 512     fprintf(mf.fp, "# Meta data file %s\n", fname);
 513
 514     mf.gn = gn;
 515
 516     Lst_ForEach(gn->commands, printCMD, &mf);
 517
 518     fprintf(mf.fp, "CWD %s\n", getcwd(buf, sizeof(buf)));
 519     fprintf(mf.fp, "TARGET %s\n", tname);
 520
 521     if (metaEnv) {
 522         for (ptr = environ; *ptr != NULL; ptr++)
 523             fprintf(mf.fp, "ENV %s\n", *ptr);
 524     }
 525
 526     fprintf(mf.fp, "-- command output --\n");
 527     fflush(mf.fp);
 528
 529     Var_Append(".MAKE.META.FILES", fname, VAR_GLOBAL);
 530     Var_Append(".MAKE.META.CREATED", fname, VAR_GLOBAL);
 531
 532     gn->type |= OP_META;                /* in case anyone wants to know */
 533     if (metaSilent) {
 534             gn->type |= OP_SILENT;
 535     }
 536  out:
 537     for (i--; i >= 0; i--) {
 538         free(p[i]);
 539     }
 540
 541     return (mf.fp);
 542 }
 543
 544 static Boolean
 545 boolValue(char *s)
 546 {
 547     switch(*s) {
 548     case '0':
 549     case 'N':
 550     case 'n':
 551     case 'F':
 552     case 'f':
 553         return FALSE;
 554     }
 555     return TRUE;
 556 }
 557
 558 /*
 559  * Initialization we need before reading makefiles.
 560  */
 561 void
 562 meta_init(void)
 563 {
 564 #ifdef USE_FILEMON
 565         /* this allows makefiles to test if we have filemon support */
 566         Var_Set(".MAKE.PATH_FILEMON", _PATH_FILEMON, VAR_GLOBAL, 0);
 567 #endif
 568 }
 569
 570
 571 #define get_mode_bf(bf, token) \
 572     if ((cp = strstr(make_mode, token))) \
 573         bf = boolValue(&cp[sizeof(token) - 1])
 574
 575 /*
 576  * Initialization we need after reading makefiles.
 577  */
 578 void
 579 meta_mode_init(const char *make_mode)
 580 {
 581     static int once = 0;
 582     char *cp;
 583
 584     useMeta = TRUE;
 585     useFilemon = TRUE;
 586     writeMeta = TRUE;
 587
 588     if (make_mode) {
 589         if (strstr(make_mode, "env"))
 590             metaEnv = TRUE;
 591         if (strstr(make_mode, "verb"))
 592             metaVerbose = TRUE;
 593         if (strstr(make_mode, "read"))
 594             writeMeta = FALSE;
 595         if (strstr(make_mode, "nofilemon"))
 596             useFilemon = FALSE;
 597         if (strstr(make_mode, "ignore-cmd"))
 598             metaIgnoreCMDs = TRUE;
 599         if (useFilemon)
 600             get_mode_bf(filemonMissing, "missing-filemon=");
 601         get_mode_bf(metaCurdirOk, "curdirok=");
 602         get_mode_bf(metaMissing, "missing-meta=");
 603         get_mode_bf(metaSilent, "silent=");
 604     }
 605     if (metaVerbose && !Var_Exists(MAKE_META_PREFIX, VAR_GLOBAL)) {
 606         /*
 607          * The default value for MAKE_META_PREFIX
 608          * prints the absolute path of the target.
 609          * This works be cause :H will generate '.' if there is no /
 610          * and :tA will resolve that to cwd.
 611          */
 612         Var_Set(MAKE_META_PREFIX, "Building ${.TARGET:H:tA}/${.TARGET:T}", VAR_GLOBAL, 0);
 613     }
 614     if (once)
 615         return;
 616     once = 1;
 617     memset(&Mybm, 0, sizeof(Mybm));
 618     /*
 619      * We consider ourselves master of all within ${.MAKE.META.BAILIWICK}
 620      */
 621     metaBailiwick = Lst_Init(FALSE);
 622     metaBailiwickStr = Var_Subst(NULL, "${.MAKE.META.BAILIWICK:O:u:tA}",
 623         VAR_GLOBAL, VARF_WANTRES);
 624     if (metaBailiwickStr) {
 625         str2Lst_Append(metaBailiwick, metaBailiwickStr, NULL);
 626     }
 627     /*
 628      * We ignore any paths that start with ${.MAKE.META.IGNORE_PATHS}
 629      */
 630     metaIgnorePaths = Lst_Init(FALSE);
 631     Var_Append(MAKE_META_IGNORE_PATHS,
 632                "/dev /etc /proc /tmp /var/run /var/tmp ${TMPDIR}", VAR_GLOBAL);
 633     metaIgnorePathsStr = Var_Subst(NULL,
 634                    "${" MAKE_META_IGNORE_PATHS ":O:u:tA}", VAR_GLOBAL,
 635                    VARF_WANTRES);
 636     if (metaIgnorePathsStr) {
 637         str2Lst_Append(metaIgnorePaths, metaIgnorePathsStr, NULL);
 638     }
 639
 640     /*
 641      * We ignore any paths that match ${.MAKE.META.IGNORE_PATTERNS}
 642      */
 643     cp = NULL;
 644     if (Var_Value(MAKE_META_IGNORE_PATTERNS, VAR_GLOBAL, &cp)) {
 645         metaIgnorePatterns = TRUE;
 646         free(cp);
 647     }
 648 }
 649
 650 /*
 651  * In each case below we allow for job==NULL
 652  */
 653 void
 654 meta_job_start(Job *job, GNode *gn)
 655 {
 656     BuildMon *pbm;
 657
 658     if (job != NULL) {
 659         pbm = &job->bm;
 660     } else {
 661         pbm = &Mybm;
 662     }
 663     pbm->mfp = meta_create(pbm, gn);
 664 #ifdef USE_FILEMON_ONCE
 665     /* compat mode we open the filemon dev once per command */
 666     if (job == NULL)
 667         return;
 668 #endif
 669 #ifdef USE_FILEMON
 670     if (pbm->mfp != NULL && useFilemon) {
 671         filemon_open(pbm);
 672     } else {
 673         pbm->mon_fd = pbm->filemon_fd = -1;
 674     }
 675 #endif
 676 }
 677
 678 /*
 679  * The child calls this before doing anything.
 680  * It does not disturb our state.
 681  */
 682 void
 683 meta_job_child(Job *job)
 684 {
 685 #ifdef USE_FILEMON
 686     BuildMon *pbm;
 687
 688     if (job != NULL) {
 689         pbm = &job->bm;
 690     } else {
 691         pbm = &Mybm;
 692     }
 693     if (pbm->mfp != NULL) {
 694         close(fileno(pbm->mfp));
 695         if (useFilemon) {
 696             pid_t pid;
 697
 698             pid = getpid();
 699             if (ioctl(pbm->filemon_fd, FILEMON_SET_PID, &pid) < 0) {
 700                 err(1, "Could not set filemon pid!");
 701             }
 702         }
 703     }
 704 #endif
 705 }
 706
 707 void
 708 meta_job_error(Job *job, GNode *gn, int flags, int status)
 709 {
 710     char cwd[MAXPATHLEN];
 711     BuildMon *pbm;
 712
 713     if (job != NULL) {
 714         pbm = &job->bm;
 715         if (!gn)
 716             gn = job->node;
 717     } else {
 718         pbm = &Mybm;
 719     }
 720     if (pbm->mfp != NULL) {
 721         fprintf(pbm->mfp, "*** Error code %d%s\n",
 722                 status,
 723                 (flags & JOB_IGNERR) ?
 724                 "(ignored)" : "");
 725     }
 726     if (gn) {
 727         Var_Set(".ERROR_TARGET", gn->path ? gn->path : gn->name, VAR_GLOBAL, 0);
 728     }
 729     getcwd(cwd, sizeof(cwd));
 730     Var_Set(".ERROR_CWD", cwd, VAR_GLOBAL, 0);
 731     if (pbm->meta_fname[0]) {
 732         Var_Set(".ERROR_META_FILE", pbm->meta_fname, VAR_GLOBAL, 0);
 733     }
 734     meta_job_finish(job);
 735 }
 736
 737 void
 738 meta_job_output(Job *job, char *cp, const char *nl)
 739 {
 740     BuildMon *pbm;
 741
 742     if (job != NULL) {
 743         pbm = &job->bm;
 744     } else {
 745         pbm = &Mybm;
 746     }
 747     if (pbm->mfp != NULL) {
 748         if (metaVerbose) {
 749             static char *meta_prefix = NULL;
 750             static int meta_prefix_len;
 751
 752             if (!meta_prefix) {
 753                 char *cp2;
 754
 755                 meta_prefix = Var_Subst(NULL, "${" MAKE_META_PREFIX "}",
 756                                         VAR_GLOBAL, VARF_WANTRES);
 757                 if ((cp2 = strchr(meta_prefix, '$')))
 758                     meta_prefix_len = cp2 - meta_prefix;
 759                 else
 760                     meta_prefix_len = strlen(meta_prefix);
 761             }
 762             if (strncmp(cp, meta_prefix, meta_prefix_len) == 0) {
 763                 cp = strchr(cp+1, '\n');
 764                 if (!cp++)
 765                     return;
 766             }
 767         }
 768         fprintf(pbm->mfp, "%s%s", cp, nl);
 769     }
 770 }
 771
 772 int
 773 meta_cmd_finish(void *pbmp)
 774 {
 775     int error = 0;
 776 #ifdef USE_FILEMON
 777     BuildMon *pbm = pbmp;
 778     int x;
 779
 780     if (!pbm)
 781         pbm = &Mybm;
 782
 783     if (pbm->filemon_fd >= 0) {
 784         if (close(pbm->filemon_fd) < 0)
 785             error = errno;
 786         x = filemon_read(pbm->mfp, pbm->mon_fd);
 787         if (error == 0 && x != 0)
 788             error = x;
 789         pbm->filemon_fd = pbm->mon_fd = -1;
 790     }
 791 #endif
 792     return error;
 793 }
 794
 795 int
 796 meta_job_finish(Job *job)
 797 {
 798     BuildMon *pbm;
 799     int error = 0;
 800     int x;
 801
 802     if (job != NULL) {
 803         pbm = &job->bm;
 804     } else {
 805         pbm = &Mybm;
 806     }
 807     if (pbm->mfp != NULL) {
 808         error = meta_cmd_finish(pbm);
 809         x = fclose(pbm->mfp);
 810         if (error == 0 && x != 0)
 811             error = errno;
 812         pbm->mfp = NULL;
 813         pbm->meta_fname[0] = '\0';
 814     }
 815     return error;
 816 }
 817
 818 void
 819 meta_finish(void)
 820 {
 821     Lst_Destroy(metaBailiwick, NULL);
 822     free(metaBailiwickStr);
 823     Lst_Destroy(metaIgnorePaths, NULL);
 824     free(metaIgnorePathsStr);
 825 }
 826
 827 /*
 828  * Fetch a full line from fp - growing bufp if needed
 829  * Return length in bufp.
 830  */
 831 static int
 832 fgetLine(char **bufp, size_t *szp, int o, FILE *fp)
 833 {
 834     char *buf = *bufp;
 835     size_t bufsz = *szp;
 836     struct stat fs;
 837     int x;
 838
 839     if (fgets(&buf[o], bufsz - o, fp) != NULL) {
 840     check_newline:
 841         x = o + strlen(&buf[o]);
 842         if (buf[x - 1] == '\n')
 843             return x;
 844         /*
 845          * We need to grow the buffer.
 846          * The meta file can give us a clue.
 847          */
 848         if (fstat(fileno(fp), &fs) == 0) {
 849             size_t newsz;
 850             char *p;
 851
 852             newsz = ROUNDUP((fs.st_size / 2), BUFSIZ);
 853             if (newsz <= bufsz)
 854                 newsz = ROUNDUP(fs.st_size, BUFSIZ);
 855             if (DEBUG(META))
 856                 fprintf(debug_file, "growing buffer %u -> %u\n",
 857                         (unsigned)bufsz, (unsigned)newsz);
 858             p = bmake_realloc(buf, newsz);
 859             if (p) {
 860                 *bufp = buf = p;
 861                 *szp = bufsz = newsz;
 862                 /* fetch the rest */
 863                 if (!fgets(&buf[x], bufsz - x, fp))
 864                     return x;           /* truncated! */
 865                 goto check_newline;
 866             }
 867         }
 868     }
 869     return 0;
 870 }
 871
 872 static int
 873 prefix_match(void *p, void *q)
 874 {
 875     const char *prefix = p;
 876     const char *path = q;
 877     size_t n = strlen(prefix);
 878
 879     return (0 == strncmp(path, prefix, n));
 880 }
 881
 882 static int
 883 string_match(const void *p, const void *q)
 884 {
 885     const char *p1 = p;
 886     const char *p2 = q;
 887
 888     return strcmp(p1, p2);
 889 }
 890
 891
 892 /*
 893  * When running with 'meta' functionality, a target can be out-of-date
 894  * if any of the references in its meta data file is more recent.
 895  * We have to track the latestdir on a per-process basis.
 896  */
 897 #define LCWD_VNAME_FMT ".meta.%d.lcwd"
 898 #define LDIR_VNAME_FMT ".meta.%d.ldir"
 899
 900 /*
 901  * It is possible that a .meta file is corrupted,
 902  * if we detect this we want to reproduce it.
 903  * Setting oodate TRUE will have that effect.
 904  */
 905 #define CHECK_VALID_META(p) if (!(p && *p)) { \
 906     warnx("%s: %d: malformed", fname, lineno); \
 907     oodate = TRUE; \
 908     continue; \
 909     }
 910
 911 #define DEQUOTE(p) if (*p == '\'') {    \
 912     char *ep; \
 913     p++; \
 914     if ((ep = strchr(p, '\''))) \
 915         *ep = '\0'; \
 916     }
 917
 918 Boolean
 919 meta_oodate(GNode *gn, Boolean oodate)
 920 {
 921     static char *tmpdir = NULL;
 922     static char cwd[MAXPATHLEN];
 923     char lcwd_vname[64];
 924     char ldir_vname[64];
 925     char lcwd[MAXPATHLEN];
 926     char latestdir[MAXPATHLEN];
 927     char fname[MAXPATHLEN];
 928     char fname1[MAXPATHLEN];
 929     char fname2[MAXPATHLEN];
 930     char fname3[MAXPATHLEN];
 931     const char *dname;
 932     const char *tname;
 933     char *p;
 934     char *cp;
 935     char *link_src;
 936     char *move_target;
 937     static size_t cwdlen = 0;
 938     static size_t tmplen = 0;
 939     FILE *fp;
 940     Boolean needOODATE = FALSE;
 941     Lst missingFiles;
 942     char *pa[4];                        /* >= possible uses */
 943     int i;
 944     int have_filemon = FALSE;
 945
 946     if (oodate)
 947         return oodate;          /* we're done */
 948
 949     i = 0;
 950
 951     dname = Var_Value(".OBJDIR", gn, &pa[i++]);
 952     tname = Var_Value(TARGET, gn, &pa[i++]);
 953
 954     /* if this succeeds fname3 is realpath of dname */
 955     if (!meta_needed(gn, dname, tname, fname3, FALSE))
 956         goto oodate_out;
 957     dname = fname3;
 958
 959     missingFiles = Lst_Init(FALSE);
 960
 961     /*
 962      * We need to check if the target is out-of-date. This includes
 963      * checking if the expanded command has changed. This in turn
 964      * requires that all variables are set in the same way that they
 965      * would be if the target needs to be re-built.
 966      */
 967     Make_DoAllVar(gn);
 968
 969     meta_name(gn, fname, sizeof(fname), dname, tname, dname);
 970
 971 #ifdef DEBUG_META_MODE
 972     if (DEBUG(META))
 973         fprintf(debug_file, "meta_oodate: %s\n", fname);
 974 #endif
 975
 976     if ((fp = fopen(fname, "r")) != NULL) {
 977         static char *buf = NULL;
 978         static size_t bufsz;
 979         int lineno = 0;
 980         int lastpid = 0;
 981         int pid;
 982         int x;
 983         LstNode ln;
 984         struct stat fs;
 985
 986         if (!buf) {
 987             bufsz = 8 * BUFSIZ;
 988             buf = bmake_malloc(bufsz);
 989         }
 990
 991         if (!cwdlen) {
 992             if (getcwd(cwd, sizeof(cwd)) == NULL)
 993                 err(1, "Could not get current working directory");
 994             cwdlen = strlen(cwd);
 995         }
 996         strlcpy(lcwd, cwd, sizeof(lcwd));
 997         strlcpy(latestdir, cwd, sizeof(latestdir));
 998
 999         if (!tmpdir) {
1000             tmpdir = getTmpdir();
1001             tmplen = strlen(tmpdir);
1002         }
1003
1004         /* we want to track all the .meta we read */
1005         Var_Append(".MAKE.META.FILES", fname, VAR_GLOBAL);
1006
1007         ln = Lst_First(gn->commands);
1008         while (!oodate && (x = fgetLine(&buf, &bufsz, 0, fp)) > 0) {
1009             lineno++;
1010             if (buf[x - 1] == '\n')
1011                 buf[x - 1] = '\0';
1012             else {
1013                 warnx("%s: %d: line truncated at %u", fname, lineno, x);
1014                 oodate = TRUE;
1015                 break;
1016             }
1017             link_src = NULL;
1018             move_target = NULL;
1019             /* Find the start of the build monitor section. */
1020             if (!have_filemon) {
1021                 if (strncmp(buf, "-- filemon", 10) == 0) {
1022                     have_filemon = TRUE;
1023                     continue;
1024                 }
1025                 if (strncmp(buf, "# buildmon", 10) == 0) {
1026                     have_filemon = TRUE;
1027                     continue;
1028                 }
1029             }
1030
1031             /* Delimit the record type. */
1032             p = buf;
1033 #ifdef DEBUG_META_MODE
1034             if (DEBUG(META))
1035                 fprintf(debug_file, "%s: %d: %s\n", fname, lineno, buf);
1036 #endif
1037             strsep(&p, " ");
1038             if (have_filemon) {
1039                 /*
1040                  * We are in the 'filemon' output section.
1041                  * Each record from filemon follows the general form:
1042                  *
1043                  * <key> <pid> <data>
1044                  *
1045                  * Where:
1046                  * <key> is a single letter, denoting the syscall.
1047                  * <pid> is the process that made the syscall.
1048                  * <data> is the arguments (of interest).
1049                  */
1050                 switch(buf[0]) {
1051                 case '#':               /* comment */
1052                 case 'V':               /* version */
1053                     break;
1054                 default:
1055                     /*
1056                      * We need to track pathnames per-process.
1057                      *
1058                      * Each process run by make, starts off in the 'CWD'
1059                      * recorded in the .meta file, if it chdirs ('C')
1060                      * elsewhere we need to track that - but only for
1061                      * that process.  If it forks ('F'), we initialize
1062                      * the child to have the same cwd as its parent.
1063                      *
1064                      * We also need to track the 'latestdir' of
1065                      * interest.  This is usually the same as cwd, but
1066                      * not if a process is reading directories.
1067                      *
1068                      * Each time we spot a different process ('pid')
1069                      * we save the current value of 'latestdir' in a
1070                      * variable qualified by 'lastpid', and
1071                      * re-initialize 'latestdir' to any pre-saved
1072                      * value for the current 'pid' and 'CWD' if none.
1073                      */
1074                     CHECK_VALID_META(p);
1075                     pid = atoi(p);
1076                     if (pid > 0 && pid != lastpid) {
1077                         char *ldir;
1078                         char *tp;
1079
1080                         if (lastpid > 0) {
1081                             /* We need to remember these. */
1082                             Var_Set(lcwd_vname, lcwd, VAR_GLOBAL, 0);
1083                             Var_Set(ldir_vname, latestdir, VAR_GLOBAL, 0);
1084                         }
1085                         snprintf(lcwd_vname, sizeof(lcwd_vname), LCWD_VNAME_FMT, pid);
1086                         snprintf(ldir_vname, sizeof(ldir_vname), LDIR_VNAME_FMT, pid);
1087                         lastpid = pid;
1088                         ldir = Var_Value(ldir_vname, VAR_GLOBAL, &tp);
1089                         if (ldir) {
1090                             strlcpy(latestdir, ldir, sizeof(latestdir));
1091                             free(tp);
1092                         }
1093                         ldir = Var_Value(lcwd_vname, VAR_GLOBAL, &tp);
1094                         if (ldir) {
1095                             strlcpy(lcwd, ldir, sizeof(lcwd));
1096                             free(tp);
1097                         }
1098                     }
1099                     /* Skip past the pid. */
1100                     if (strsep(&p, " ") == NULL)
1101                         continue;
1102 #ifdef DEBUG_META_MODE
1103                     if (DEBUG(META))
1104                             fprintf(debug_file, "%s: %d: %d: %c: cwd=%s lcwd=%s ldir=%s\n",
1105                                     fname, lineno,
1106                                     pid, buf[0], cwd, lcwd, latestdir);
1107 #endif
1108                     break;
1109                 }
1110
1111                 CHECK_VALID_META(p);
1112
1113                 /* Process according to record type. */
1114                 switch (buf[0]) {
1115                 case 'X':               /* eXit */
1116                     Var_Delete(lcwd_vname, VAR_GLOBAL);
1117                     Var_Delete(ldir_vname, VAR_GLOBAL);
1118                     lastpid = 0;        /* no need to save ldir_vname */
1119                     break;
1120
1121                 case 'F':               /* [v]Fork */
1122                     {
1123                         char cldir[64];
1124                         int child;
1125
1126                         child = atoi(p);
1127                         if (child > 0) {
1128                             snprintf(cldir, sizeof(cldir), LCWD_VNAME_FMT, child);
1129                             Var_Set(cldir, lcwd, VAR_GLOBAL, 0);
1130                             snprintf(cldir, sizeof(cldir), LDIR_VNAME_FMT, child);
1131                             Var_Set(cldir, latestdir, VAR_GLOBAL, 0);
1132 #ifdef DEBUG_META_MODE
1133                             if (DEBUG(META))
1134                                     fprintf(debug_file, "%s: %d: %d: cwd=%s lcwd=%s ldir=%s\n",
1135                                             fname, lineno,
1136                                             child, cwd, lcwd, latestdir);
1137 #endif
1138                         }
1139                     }
1140                     break;
1141
1142                 case 'C':               /* Chdir */
1143                     /* Update lcwd and latest directory. */
1144                     strlcpy(latestdir, p, sizeof(latestdir));
1145                     strlcpy(lcwd, p, sizeof(lcwd));
1146                     Var_Set(lcwd_vname, lcwd, VAR_GLOBAL, 0);
1147                     Var_Set(ldir_vname, lcwd, VAR_GLOBAL, 0);
1148 #ifdef DEBUG_META_MODE
1149                     if (DEBUG(META))
1150                         fprintf(debug_file, "%s: %d: cwd=%s ldir=%s\n", fname, lineno, cwd, lcwd);
1151 #endif
1152                     break;
1153
1154                 case 'M':               /* renaMe */
1155                     /*
1156                      * For 'M'oves we want to check
1157                      * the src as for 'R'ead
1158                      * and the target as for 'W'rite.
1159                      */
1160                     cp = p;             /* save this for a second */
1161                     /* now get target */
1162                     if (strsep(&p, " ") == NULL)
1163                         continue;
1164                     CHECK_VALID_META(p);
1165                     move_target = p;
1166                     p = cp;
1167                     /* 'L' and 'M' put single quotes around the args */
1168                     DEQUOTE(p);
1169                     DEQUOTE(move_target);
1170                     /* FALLTHROUGH */
1171                 case 'D':               /* unlink */
1172                     if (*p == '/' && !Lst_IsEmpty(missingFiles)) {
1173                         /* remove p from the missingFiles list if present */
1174                         if ((ln = Lst_Find(missingFiles, p, string_match)) != NULL) {
1175                             char *tp = Lst_Datum(ln);
1176                             Lst_Remove(missingFiles, ln);
1177                             free(tp);
1178                             ln = NULL;  /* we're done with it */
1179                         }
1180                     }
1181                     if (buf[0] == 'M') {
1182                         /* the target of the mv is a file 'W'ritten */
1183 #ifdef DEBUG_META_MODE
1184                         if (DEBUG(META))
1185                             fprintf(debug_file, "meta_oodate: M %s -> %s\n",
1186                                     p, move_target);
1187 #endif
1188                         p = move_target;
1189                         goto check_write;
1190                     }
1191                     break;
1192                 case 'L':               /* Link */
1193                     /*
1194                      * For 'L'inks check
1195                      * the src as for 'R'ead
1196                      * and the target as for 'W'rite.
1197                      */
1198                     link_src = p;
1199                     /* now get target */
1200                     if (strsep(&p, " ") == NULL)
1201                         continue;
1202                     CHECK_VALID_META(p);
1203                     /* 'L' and 'M' put single quotes around the args */
1204                     DEQUOTE(p);
1205                     DEQUOTE(link_src);
1206 #ifdef DEBUG_META_MODE
1207                     if (DEBUG(META))
1208                         fprintf(debug_file, "meta_oodate: L %s -> %s\n",
1209                                 link_src, p);
1210 #endif
1211                     /* FALLTHROUGH */
1212                 case 'W':               /* Write */
1213                 check_write:
1214                     /*
1215                      * If a file we generated within our bailiwick
1216                      * but outside of .OBJDIR is missing,
1217                      * we need to do it again.
1218                      */
1219                     /* ignore non-absolute paths */
1220                     if (*p != '/')
1221                         break;
1222
1223                     if (Lst_IsEmpty(metaBailiwick))
1224                         break;
1225
1226                     /* ignore cwd - normal dependencies handle those */
1227                     if (strncmp(p, cwd, cwdlen) == 0)
1228                         break;
1229
1230                     if (!Lst_ForEach(metaBailiwick, prefix_match, p))
1231                         break;
1232
1233                     /* tmpdir might be within */
1234                     if (tmplen > 0 && strncmp(p, tmpdir, tmplen) == 0)
1235                         break;
1236
1237                     /* ignore anything containing the string "tmp" */
1238                     if ((strstr("tmp", p)))
1239                         break;
1240
1241                     if ((link_src != NULL && cached_lstat(p, &fs) < 0) ||
1242                         (link_src == NULL && cached_stat(p, &fs) < 0)) {
1243                         if (Lst_Find(missingFiles, p, string_match) == NULL)
1244                                 Lst_AtEnd(missingFiles, bmake_strdup(p));
1245                     }
1246                     break;
1247                 check_link_src:
1248                     p = link_src;
1249                     link_src = NULL;
1250 #ifdef DEBUG_META_MODE
1251                     if (DEBUG(META))
1252                         fprintf(debug_file, "meta_oodate: L src %s\n", p);
1253 #endif
1254                     /* FALLTHROUGH */
1255                 case 'R':               /* Read */
1256                 case 'E':               /* Exec */
1257                     /*
1258                      * Check for runtime files that can't
1259                      * be part of the dependencies because
1260                      * they are _expected_ to change.
1261                      */
1262                     if (*p == '/') {
1263                         cached_realpath(p, fname1); /* clean it up */
1264                         if (Lst_ForEach(metaIgnorePaths, prefix_match, fname1)) {
1265 #ifdef DEBUG_META_MODE
1266                             if (DEBUG(META))
1267                                 fprintf(debug_file, "meta_oodate: ignoring path: %s\n",
1268                                         p);
1269 #endif
1270                             break;
1271                         }
1272                     }
1273
1274                     if (metaIgnorePatterns) {
1275                         char *pm;
1276
1277                         snprintf(fname1, sizeof(fname1),
1278                                  "${%s:@m@${%s:L:M$m}@}",
1279                                  MAKE_META_IGNORE_PATTERNS, p);
1280                         pm = Var_Subst(NULL, fname1, gn, VARF_WANTRES);
1281                         if (*pm) {
1282 #ifdef DEBUG_META_MODE
1283                             if (DEBUG(META))
1284                                 fprintf(debug_file, "meta_oodate: ignoring pattern: %s\n",
1285                                         p);
1286 #endif
1287                             free(pm);
1288                             break;
1289                         }
1290                         free(pm);
1291                     }
1292
1293                     /*
1294                      * The rest of the record is the file name.
1295                      * Check if it's not an absolute path.
1296                      */
1297                     {
1298                         char *sdirs[4];
1299                         char **sdp;
1300                         int sdx = 0;
1301                         int found = 0;
1302
1303                         if (*p == '/') {
1304                             sdirs[sdx++] = p; /* done */
1305                         } else {
1306                             if (strcmp(".", p) == 0)
1307                                 continue;  /* no point */
1308
1309                             /* Check vs latestdir */
1310                             snprintf(fname1, sizeof(fname1), "%s/%s", latestdir, p);
1311                             sdirs[sdx++] = fname1;
1312
1313                             if (strcmp(latestdir, lcwd) != 0) {
1314                                 /* Check vs lcwd */
1315                                 snprintf(fname2, sizeof(fname2), "%s/%s", lcwd, p);
1316                                 sdirs[sdx++] = fname2;
1317                             }
1318                             if (strcmp(lcwd, cwd) != 0) {
1319                                 /* Check vs cwd */
1320                                 snprintf(fname3, sizeof(fname3), "%s/%s", cwd, p);
1321                                 sdirs[sdx++] = fname3;
1322                             }
1323                         }
1324                         sdirs[sdx++] = NULL;
1325
1326                         for (sdp = sdirs; *sdp && !found; sdp++) {
1327 #ifdef DEBUG_META_MODE
1328                             if (DEBUG(META))
1329                                 fprintf(debug_file, "%s: %d: looking for: %s\n", fname, lineno, *sdp);
1330 #endif
1331                             if (cached_stat(*sdp, &fs) == 0) {
1332                                 found = 1;
1333                                 p = *sdp;
1334                             }
1335                         }
1336                         if (found) {
1337 #ifdef DEBUG_META_MODE
1338                             if (DEBUG(META))
1339                                 fprintf(debug_file, "%s: %d: found: %s\n", fname, lineno, p);
1340 #endif
1341                             if (!S_ISDIR(fs.st_mode) &&
1342                                 fs.st_mtime > gn->mtime) {
1343                                 if (DEBUG(META))
1344                                     fprintf(debug_file, "%s: %d: file '%s' is newer than the target...\n", fname, lineno, p);
1345                                 oodate = TRUE;
1346                             } else if (S_ISDIR(fs.st_mode)) {
1347                                 /* Update the latest directory. */
1348                                 cached_realpath(p, latestdir);
1349                             }
1350                         } else if (errno == ENOENT && *p == '/' &&
1351                                    strncmp(p, cwd, cwdlen) != 0) {
1352                             /*
1353                              * A referenced file outside of CWD is missing.
1354                              * We cannot catch every eventuality here...
1355                              */
1356                             if (Lst_Find(missingFiles, p, string_match) == NULL)
1357                                     Lst_AtEnd(missingFiles, bmake_strdup(p));
1358                         }
1359                     }
1360                     if (buf[0] == 'E') {
1361                         /* previous latestdir is no longer relevant */
1362                         strlcpy(latestdir, lcwd, sizeof(latestdir));
1363                     }
1364                     break;
1365                 default:
1366                     break;
1367                 }
1368                 if (!oodate && buf[0] == 'L' && link_src != NULL)
1369                     goto check_link_src;
1370             } else if (strcmp(buf, "CMD") == 0) {
1371                 /*
1372                  * Compare the current command with the one in the
1373                  * meta data file.
1374                  */
1375                 if (ln == NULL) {
1376                     if (DEBUG(META))
1377                         fprintf(debug_file, "%s: %d: there were more build commands in the meta data file than there are now...\n", fname, lineno);
1378                     oodate = TRUE;
1379                 } else {
1380                     char *cmd = (char *)Lst_Datum(ln);
1381                     Boolean hasOODATE = FALSE;
1382
1383                     if (strstr(cmd, "$?"))
1384                         hasOODATE = TRUE;
1385                     else if ((cp = strstr(cmd, ".OODATE"))) {
1386                         /* check for $[{(].OODATE[:)}] */
1387                         if (cp > cmd + 2 && cp[-2] == '$')
1388                             hasOODATE = TRUE;
1389                     }
1390                     if (hasOODATE) {
1391                         needOODATE = TRUE;
1392                         if (DEBUG(META))
1393                             fprintf(debug_file, "%s: %d: cannot compare command using .OODATE\n", fname, lineno);
1394                     }
1395                     cmd = Var_Subst(NULL, cmd, gn, VARF_WANTRES|VARF_UNDEFERR);
1396
1397                     if ((cp = strchr(cmd, '\n'))) {
1398                         int n;
1399
1400                         /*
1401                          * This command contains newlines, we need to
1402                          * fetch more from the .meta file before we
1403                          * attempt a comparison.
1404                          */
1405                         /* first put the newline back at buf[x - 1] */
1406                         buf[x - 1] = '\n';
1407                         do {
1408                             /* now fetch the next line */
1409                             if ((n = fgetLine(&buf, &bufsz, x, fp)) <= 0)
1410                                 break;
1411                             x = n;
1412                             lineno++;
1413                             if (buf[x - 1] != '\n') {
1414                                 warnx("%s: %d: line truncated at %u", fname, lineno, x);
1415                                 break;
1416                             }
1417                             cp = strchr(++cp, '\n');
1418                         } while (cp);
1419                         if (buf[x - 1] == '\n')
1420                             buf[x - 1] = '\0';
1421                     }
1422                     if (!hasOODATE &&
1423                         !(gn->type & OP_NOMETA_CMP) &&
1424                         strcmp(p, cmd) != 0) {
1425                         if (DEBUG(META))
1426                             fprintf(debug_file, "%s: %d: a build command has changed\n%s\nvs\n%s\n", fname, lineno, p, cmd);
1427                         if (!metaIgnoreCMDs)
1428                             oodate = TRUE;
1429                     }
1430                     free(cmd);
1431                     ln = Lst_Succ(ln);
1432                 }
1433             } else if (strcmp(buf, "CWD") == 0) {
1434                 /*
1435                  * Check if there are extra commands now
1436                  * that weren't in the meta data file.
1437                  */
1438                 if (!oodate && ln != NULL) {
1439                     if (DEBUG(META))
1440                         fprintf(debug_file, "%s: %d: there are extra build commands now that weren't in the meta data file\n", fname, lineno);
1441                     oodate = TRUE;
1442                 }
1443                 if (strcmp(p, cwd) != 0) {
1444                     if (DEBUG(META))
1445                         fprintf(debug_file, "%s: %d: the current working directory has changed from '%s' to '%s'\n", fname, lineno, p, curdir);
1446                     oodate = TRUE;
1447                 }
1448             }
1449         }
1450
1451         fclose(fp);
1452         if (!Lst_IsEmpty(missingFiles)) {
1453             if (DEBUG(META))
1454                 fprintf(debug_file, "%s: missing files: %s...\n",
1455                         fname, (char *)Lst_Datum(Lst_First(missingFiles)));
1456             oodate = TRUE;
1457         }
1458         if (!oodate && !have_filemon && filemonMissing) {
1459             if (DEBUG(META))
1460                 fprintf(debug_file, "%s: missing filemon data\n", fname);
1461             oodate = TRUE;
1462         }
1463     } else {
1464         if (writeMeta && metaMissing) {
1465             cp = NULL;
1466
1467             /* if target is in .CURDIR we do not need a meta file */
1468             if (gn->path && (cp = strrchr(gn->path, '/')) && cp > gn->path) {
1469                 if (strncmp(curdir, gn->path, (cp - gn->path)) != 0) {
1470                     cp = NULL;          /* not in .CURDIR */
1471                 }
1472             }
1473             if (!cp) {
1474                 if (DEBUG(META))
1475                     fprintf(debug_file, "%s: required but missing\n", fname);
1476                 oodate = TRUE;
1477             }
1478         }
1479     }
1480
1481     Lst_Destroy(missingFiles, (FreeProc *)free);
1482
1483     if (oodate && needOODATE) {
1484         /*
1485          * Target uses .OODATE which is empty; or we wouldn't be here.
1486          * We have decided it is oodate, so .OODATE needs to be set.
1487          * All we can sanely do is set it to .ALLSRC.
1488          */
1489         Var_Delete(OODATE, gn);
1490         Var_Set(OODATE, Var_Value(ALLSRC, gn, &cp), gn, 0);
1491         free(cp);
1492     }
1493
1494  oodate_out:
1495     for (i--; i >= 0; i--) {
1496         free(pa[i]);
1497     }
1498     return oodate;
1499 }
1500
1501 /* support for compat mode */
1502
1503 static int childPipe[2];
1504
1505 void
1506 meta_compat_start(void)
1507 {
1508 #ifdef USE_FILEMON_ONCE
1509     /*
1510      * We need to re-open filemon for each cmd.
1511      */
1512     BuildMon *pbm = &Mybm;
1513
1514     if (pbm->mfp != NULL && useFilemon) {
1515         filemon_open(pbm);
1516     } else {
1517         pbm->mon_fd = pbm->filemon_fd = -1;
1518     }
1519 #endif
1520     if (pipe(childPipe) < 0)
1521         Punt("Cannot create pipe: %s", strerror(errno));
1522     /* Set close-on-exec flag for both */
1523     (void)fcntl(childPipe[0], F_SETFD, FD_CLOEXEC);
1524     (void)fcntl(childPipe[1], F_SETFD, FD_CLOEXEC);
1525 }
1526
1527 void
1528 meta_compat_child(void)
1529 {
1530     meta_job_child(NULL);
1531     if (dup2(childPipe[1], 1) < 0 ||
1532         dup2(1, 2) < 0) {
1533         execError("dup2", "pipe");
1534         _exit(1);
1535     }
1536 }
1537
1538 void
1539 meta_compat_parent(void)
1540 {
1541     FILE *fp;
1542     char buf[BUFSIZ];
1543
1544     close(childPipe[1]);                        /* child side */
1545     fp = fdopen(childPipe[0], "r");
1546     while (fgets(buf, sizeof(buf), fp)) {
1547         meta_job_output(NULL, buf, "");
1548         printf("%s", buf);
1549     }
1550     fclose(fp);
1551 }
1552
1553 #endif  /* USE_META */