misc.c

   1 /* Miscellaneous generic support functions for GNU Make.
   2 Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1997,
   3 2002 Free Software Foundation, Inc.
   4 This file is part of GNU Make.
   5
   6 GNU Make is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Make is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Make; see the file COPYING.  If not, write to
  18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #include "make.h"
  22 #include "dep.h"
  23 #include "debug.h"
  24
  25 /* Variadic functions.  We go through contortions to allow proper function
  26    prototypes for both ANSI and pre-ANSI C compilers, and also for those
  27    which support stdarg.h vs. varargs.h, and finally those which have
  28    vfprintf(), etc. and those who have _doprnt... or nothing.
  29
  30    This fancy stuff all came from GNU fileutils, except for the VA_PRINTF and
  31    VA_END macros used here since we have multiple print functions.  */
  32
  33 #if HAVE_VPRINTF || HAVE_DOPRNT
  34 # define HAVE_STDVARARGS 1
  35 # if __STDC__
  36 #  include <stdarg.h>
  37 #  define VA_START(args, lastarg) va_start(args, lastarg)
  38 # else
  39 #  include <varargs.h>
  40 #  define VA_START(args, lastarg) va_start(args)
  41 # endif
  42 # if HAVE_VPRINTF
  43 #  define VA_PRINTF(fp, lastarg, args) vfprintf((fp), (lastarg), (args))
  44 # else
  45 #  define VA_PRINTF(fp, lastarg, args) _doprnt((lastarg), (args), (fp))
  46 # endif
  47 # define VA_END(args) va_end(args)
  48 #else
  49 /* # undef HAVE_STDVARARGS */
  50 # define va_alist a1, a2, a3, a4, a5, a6, a7, a8
  51 # define va_dcl char *a1, *a2, *a3, *a4, *a5, *a6, *a7, *a8;
  52 # define VA_START(args, lastarg)
  53 # define VA_PRINTF(fp, lastarg, args) fprintf((fp), (lastarg), va_alist)
  54 # define VA_END(args)
  55 #endif
  56
  57
  58 /* Compare strings *S1 and *S2.
  59    Return negative if the first is less, positive if it is greater,
  60    zero if they are equal.  */
  61
  62 int
  63 alpha_compare (const void *v1, const void *v2)
  64 {
  65   const char *s1 = *((char **)v1);
  66   const char *s2 = *((char **)v2);
  67
  68   if (*s1 != *s2)
  69     return *s1 - *s2;
  70   return strcmp (s1, s2);
  71 }
  72 \f
  73 /* Discard each backslash-newline combination from LINE.
  74    Backslash-backslash-newline combinations become backslash-newlines.
  75    This is done by copying the text at LINE into itself.  */
  76
  77 void
  78 collapse_continuations (char *line)
  79 {
  80   register char *in, *out, *p;
  81   register int backslash;
  82   register unsigned int bs_write;
  83
  84   in = strchr (line, '\n');
  85   if (in == 0)
  86     return;
  87
  88   out = in;
  89   while (out > line && out[-1] == '\\')
  90     --out;
  91
  92   while (*in != '\0')
  93     {
  94       /* BS_WRITE gets the number of quoted backslashes at
  95          the end just before IN, and BACKSLASH gets nonzero
  96          if the next character is quoted.  */
  97       backslash = 0;
  98       bs_write = 0;
  99       for (p = in - 1; p >= line && *p == '\\'; --p)
 100         {
 101           if (backslash)
 102             ++bs_write;
 103           backslash = !backslash;
 104
 105           /* It should be impossible to go back this far without exiting,
 106              but if we do, we can't get the right answer.  */
 107           if (in == out - 1)
 108             abort ();
 109         }
 110
 111       /* Output the appropriate number of backslashes.  */
 112       while (bs_write-- > 0)
 113         *out++ = '\\';
 114
 115       /* Skip the newline.  */
 116       ++in;
 117
 118       /* If the newline is quoted, discard following whitespace
 119          and any preceding whitespace; leave just one space.  */
 120       if (backslash)
 121         {
 122           in = next_token (in);
 123           while (out > line && isblank ((unsigned char)out[-1]))
 124             --out;
 125           *out++ = ' ';
 126         }
 127       else
 128         /* If the newline isn't quoted, put it in the output.  */
 129         *out++ = '\n';
 130
 131       /* Now copy the following line to the output.
 132          Stop when we find backslashes followed by a newline.  */
 133       while (*in != '\0')
 134         if (*in == '\\')
 135           {
 136             p = in + 1;
 137             while (*p == '\\')
 138               ++p;
 139             if (*p == '\n')
 140               {
 141                 in = p;
 142                 break;
 143               }
 144             while (in < p)
 145               *out++ = *in++;
 146           }
 147         else
 148           *out++ = *in++;
 149     }
 150
 151   *out = '\0';
 152 }
 153
 154
 155 /* Remove comments from LINE.
 156    This is done by copying the text at LINE onto itself.  */
 157
 158 void
 159 remove_comments (char *line)
 160 {
 161   char *comment;
 162
 163   comment = find_char_unquote (line, '#', 0, 0);
 164
 165   if (comment != 0)
 166     /* Cut off the line at the #.  */
 167     *comment = '\0';
 168 }
 169 \f
 170 /* Print N spaces (used in debug for target-depth).  */
 171
 172 void
 173 print_spaces (unsigned int n)
 174 {
 175   while (n-- > 0)
 176     putchar (' ');
 177 }
 178
 179 \f
 180 /* Return a newly-allocated string whose contents
 181    concatenate those of s1, s2, s3.  */
 182
 183 char *
 184 concat (const char *s1, const char *s2, const char *s3)
 185 {
 186   unsigned int len1, len2, len3;
 187   char *result;
 188
 189   len1 = *s1 != '\0' ? strlen (s1) : 0;
 190   len2 = *s2 != '\0' ? strlen (s2) : 0;
 191   len3 = *s3 != '\0' ? strlen (s3) : 0;
 192
 193   result = (char *) xmalloc (len1 + len2 + len3 + 1);
 194
 195   if (*s1 != '\0')
 196     bcopy (s1, result, len1);
 197   if (*s2 != '\0')
 198     bcopy (s2, result + len1, len2);
 199   if (*s3 != '\0')
 200     bcopy (s3, result + len1 + len2, len3);
 201   *(result + len1 + len2 + len3) = '\0';
 202
 203   return result;
 204 }
 205 \f
 206 /* Print a message on stdout.  */
 207
 208 void
 209 #if __STDC__ && HAVE_STDVARARGS
 210 message (int prefix, const char *fmt, ...)
 211 #else
 212 message (prefix, fmt, va_alist)
 213      int prefix;
 214      const char *fmt;
 215      va_dcl
 216 #endif
 217 {
 218 #if HAVE_STDVARARGS
 219   va_list args;
 220 #endif
 221
 222   log_working_directory (1);
 223
 224   if (fmt != 0)
 225     {
 226       if (prefix)
 227         {
 228           if (makelevel == 0)
 229             printf ("%s: ", program);
 230           else
 231             printf ("%s[%u]: ", program, makelevel);
 232         }
 233       VA_START (args, fmt);
 234       VA_PRINTF (stdout, fmt, args);
 235       VA_END (args);
 236       putchar ('\n');
 237     }
 238
 239   fflush (stdout);
 240 }
 241
 242 /* Print an error message.  */
 243
 244 void
 245 #if __STDC__ && HAVE_STDVARARGS
 246 error (const struct floc *flocp, const char *fmt, ...)
 247 #else
 248 error (flocp, fmt, va_alist)
 249      const struct floc *flocp;
 250      const char *fmt;
 251      va_dcl
 252 #endif
 253 {
 254 #if HAVE_STDVARARGS
 255   va_list args;
 256 #endif
 257
 258   log_working_directory (1);
 259
 260   if (flocp && flocp->filenm)
 261     fprintf (stderr, "%s:%lu: ", flocp->filenm, flocp->lineno);
 262   else if (makelevel == 0)
 263     fprintf (stderr, "%s: ", program);
 264   else
 265     fprintf (stderr, "%s[%u]: ", program, makelevel);
 266
 267   VA_START(args, fmt);
 268   VA_PRINTF (stderr, fmt, args);
 269   VA_END (args);
 270
 271   putc ('\n', stderr);
 272   fflush (stderr);
 273 }
 274
 275 /* Print an error message and exit.  */
 276
 277 void
 278 #if __STDC__ && HAVE_STDVARARGS
 279 fatal (const struct floc *flocp, const char *fmt, ...)
 280 #else
 281 fatal (flocp, fmt, va_alist)
 282      const struct floc *flocp;
 283      const char *fmt;
 284      va_dcl
 285 #endif
 286 {
 287 #if HAVE_STDVARARGS
 288   va_list args;
 289 #endif
 290
 291   log_working_directory (1);
 292
 293   if (flocp && flocp->filenm)
 294     fprintf (stderr, "%s:%lu: *** ", flocp->filenm, flocp->lineno);
 295   else if (makelevel == 0)
 296     fprintf (stderr, "%s: *** ", program);
 297   else
 298     fprintf (stderr, "%s[%u]: *** ", program, makelevel);
 299
 300   VA_START(args, fmt);
 301   VA_PRINTF (stderr, fmt, args);
 302   VA_END (args);
 303
 304   fputs (_(".  Stop.\n"), stderr);
 305
 306   die (2);
 307 }
 308
 309 #ifndef HAVE_STRERROR
 310
 311 #undef  strerror
 312
 313 char *
 314 strerror (int errnum)
 315 {
 316   extern int errno, sys_nerr;
 317 #ifndef __DECC
 318   extern char *sys_errlist[];
 319 #endif
 320   static char buf[] = "Unknown error 12345678901234567890";
 321
 322   if (errno < sys_nerr)
 323     return sys_errlist[errnum];
 324
 325   sprintf (buf, _("Unknown error %d"), errnum);
 326   return buf;
 327 }
 328 #endif
 329
 330 /* Print an error message from errno.  */
 331
 332 void
 333 perror_with_name (const char *str, const char *name)
 334 {
 335   error (NILF, _("%s%s: %s"), str, name, strerror (errno));
 336 }
 337
 338 /* Print an error message from errno and exit.  */
 339
 340 void
 341 pfatal_with_name (const char *name)
 342 {
 343   fatal (NILF, _("%s: %s"), name, strerror (errno));
 344
 345   /* NOTREACHED */
 346 }
 347 \f
 348 /* Like malloc but get fatal error if memory is exhausted.  */
 349 /* Don't bother if we're using dmalloc; it provides these for us.  */
 350
 351 #ifndef HAVE_DMALLOC_H
 352
 353 #undef xmalloc
 354 #undef xrealloc
 355 #undef xstrdup
 356
 357 char *
 358 xmalloc (unsigned int size)
 359 {
 360   char *result = (char *) malloc (size);
 361   if (result == 0)
 362     fatal (NILF, _("virtual memory exhausted"));
 363   return result;
 364 }
 365
 366
 367 char *
 368 xrealloc (char *ptr, unsigned int size)
 369 {
 370   char *result;
 371
 372   /* Some older implementations of realloc() don't conform to ANSI.  */
 373   result = ptr ? realloc (ptr, size) : malloc (size);
 374   if (result == 0)
 375     fatal (NILF, _("virtual memory exhausted"));
 376   return result;
 377 }
 378
 379
 380 char *
 381 xstrdup (const char *ptr)
 382 {
 383   char *result;
 384
 385 #ifdef HAVE_STRDUP
 386   result = strdup (ptr);
 387 #else
 388   result = (char *) malloc (strlen (ptr) + 1);
 389 #endif
 390
 391   if (result == 0)
 392     fatal (NILF, _("virtual memory exhausted"));
 393
 394 #ifdef HAVE_STRDUP
 395   return result;
 396 #else
 397   return strcpy(result, ptr);
 398 #endif
 399 }
 400
 401 #endif  /* HAVE_DMALLOC_H */
 402
 403 char *
 404 savestring (const char *str, unsigned int length)
 405 {
 406   register char *out = (char *) xmalloc (length + 1);
 407   if (length > 0)
 408     bcopy (str, out, length);
 409   out[length] = '\0';
 410   return out;
 411 }
 412 \f
 413 /* Search string BIG (length BLEN) for an occurrence of
 414    string SMALL (length SLEN).  Return a pointer to the
 415    beginning of the first occurrence, or return nil if none found.  */
 416
 417 char *
 418 sindex (const char *big, unsigned int blen,
 419         const char *small, unsigned int slen)
 420 {
 421   if (!blen)
 422     blen = strlen (big);
 423   if (!slen)
 424     slen = strlen (small);
 425
 426   if (slen && blen >= slen)
 427     {
 428       register unsigned int b;
 429
 430       /* Quit when there's not enough room left for the small string.  */
 431       --slen;
 432       blen -= slen;
 433
 434       for (b = 0; b < blen; ++b, ++big)
 435         if (*big == *small && strneq (big + 1, small + 1, slen))
 436           return (char *)big;
 437     }
 438
 439   return 0;
 440 }
 441
 442 /* Limited INDEX:
 443    Search through the string STRING, which ends at LIMIT, for the character C.
 444    Returns a pointer to the first occurrence, or nil if none is found.
 445    Like INDEX except that the string searched ends where specified
 446    instead of at the first null.  */
 447
 448 char *
 449 lindex (const char *s, const char *limit, int c)
 450 {
 451   while (s < limit)
 452     if (*s++ == c)
 453       return (char *)(s - 1);
 454
 455   return 0;
 456 }
 457 \f
 458 /* Return the address of the first whitespace or null in the string S.  */
 459
 460 char *
 461 end_of_token (char *s)
 462 {
 463   while (*s != '\0' && !isblank ((unsigned char)*s))
 464     ++s;
 465   return s;
 466 }
 467
 468 #ifdef WINDOWS32
 469 /*
 470  * Same as end_of_token, but take into account a stop character
 471  */
 472 char *
 473 end_of_token_w32 (char *s, char stopchar)
 474 {
 475   register char *p = s;
 476   register int backslash = 0;
 477
 478   while (*p != '\0' && *p != stopchar
 479          && (backslash || !isblank ((unsigned char)*p)))
 480     {
 481       if (*p++ == '\\')
 482         {
 483           backslash = !backslash;
 484           while (*p == '\\')
 485             {
 486               backslash = !backslash;
 487               ++p;
 488             }
 489         }
 490       else
 491         backslash = 0;
 492     }
 493
 494   return p;
 495 }
 496 #endif
 497
 498 /* Return the address of the first nonwhitespace or null in the string S.  */
 499
 500 char *
 501 next_token (const char *s)
 502 {
 503   while (isblank ((unsigned char)*s))
 504     ++s;
 505   return (char *)s;
 506 }
 507
 508 /* Find the next token in PTR; return the address of it, and store the
 509    length of the token into *LENGTHPTR if LENGTHPTR is not nil.  */
 510
 511 char *
 512 find_next_token (char **ptr, unsigned int *lengthptr)
 513 {
 514   char *p = next_token (*ptr);
 515   char *end;
 516
 517   if (*p == '\0')
 518     return 0;
 519
 520   *ptr = end = end_of_token (p);
 521   if (lengthptr != 0)
 522     *lengthptr = end - p;
 523   return p;
 524 }
 525 \f
 526 /* Copy a chain of `struct dep', making a new chain
 527    with the same contents as the old one.  */
 528
 529 struct dep *
 530 copy_dep_chain (struct dep *d)
 531 {
 532   register struct dep *c;
 533   struct dep *firstnew = 0;
 534   struct dep *lastnew = 0;
 535
 536   while (d != 0)
 537     {
 538       c = (struct dep *) xmalloc (sizeof (struct dep));
 539       bcopy ((char *) d, (char *) c, sizeof (struct dep));
 540       if (c->name != 0)
 541         c->name = xstrdup (c->name);
 542       c->next = 0;
 543       if (firstnew == 0)
 544         firstnew = lastnew = c;
 545       else
 546         lastnew = lastnew->next = c;
 547
 548       d = d->next;
 549     }
 550
 551   return firstnew;
 552 }
 553 \f
 554 #ifdef  iAPX286
 555 /* The losing compiler on this machine can't handle this macro.  */
 556
 557 char *
 558 dep_name (struct dep *dep)
 559 {
 560   return dep->name == 0 ? dep->file->name : dep->name;
 561 }
 562 #endif
 563 \f
 564 #ifdef  GETLOADAVG_PRIVILEGED
 565
 566 #ifdef POSIX
 567
 568 /* Hopefully if a system says it's POSIX.1 and has the setuid and setgid
 569    functions, they work as POSIX.1 says.  Some systems (Alpha OSF/1 1.2,
 570    for example) which claim to be POSIX.1 also have the BSD setreuid and
 571    setregid functions, but they don't work as in BSD and only the POSIX.1
 572    way works.  */
 573
 574 #undef HAVE_SETREUID
 575 #undef HAVE_SETREGID
 576
 577 #else   /* Not POSIX.  */
 578
 579 /* Some POSIX.1 systems have the seteuid and setegid functions.  In a
 580    POSIX-like system, they are the best thing to use.  However, some
 581    non-POSIX systems have them too but they do not work in the POSIX style
 582    and we must use setreuid and setregid instead.  */
 583
 584 #undef HAVE_SETEUID
 585 #undef HAVE_SETEGID
 586
 587 #endif  /* POSIX.  */
 588
 589 #ifndef HAVE_UNISTD_H
 590 extern int getuid (), getgid (), geteuid (), getegid ();
 591 extern int setuid (), setgid ();
 592 #ifdef HAVE_SETEUID
 593 extern int seteuid ();
 594 #else
 595 #ifdef  HAVE_SETREUID
 596 extern int setreuid ();
 597 #endif  /* Have setreuid.  */
 598 #endif  /* Have seteuid.  */
 599 #ifdef HAVE_SETEGID
 600 extern int setegid ();
 601 #else
 602 #ifdef  HAVE_SETREGID
 603 extern int setregid ();
 604 #endif  /* Have setregid.  */
 605 #endif  /* Have setegid.  */
 606 #endif  /* No <unistd.h>.  */
 607
 608 /* Keep track of the user and group IDs for user- and make- access.  */
 609 static int user_uid = -1, user_gid = -1, make_uid = -1, make_gid = -1;
 610 #define access_inited   (user_uid != -1)
 611 static enum { make, user } current_access;
 612
 613
 614 /* Under -d, write a message describing the current IDs.  */
 615
 616 static void
 617 log_access (char *flavor)
 618 {
 619   if (! ISDB (DB_JOBS))
 620     return;
 621
 622   /* All the other debugging messages go to stdout,
 623      but we write this one to stderr because it might be
 624      run in a child fork whose stdout is piped.  */
 625
 626   fprintf (stderr, _("%s: user %lu (real %lu), group %lu (real %lu)\n"),
 627            flavor, (unsigned long) geteuid (), (unsigned long) getuid (),
 628            (unsigned long) getegid (), (unsigned long) getgid ());
 629   fflush (stderr);
 630 }
 631
 632
 633 static void
 634 init_access (void)
 635 {
 636 #ifndef VMS
 637   user_uid = getuid ();
 638   user_gid = getgid ();
 639
 640   make_uid = geteuid ();
 641   make_gid = getegid ();
 642
 643   /* Do these ever fail?  */
 644   if (user_uid == -1 || user_gid == -1 || make_uid == -1 || make_gid == -1)
 645     pfatal_with_name ("get{e}[gu]id");
 646
 647   log_access (_("Initialized access"));
 648
 649   current_access = make;
 650 #endif
 651 }
 652
 653 #endif  /* GETLOADAVG_PRIVILEGED */
 654
 655 /* Give the process appropriate permissions for access to
 656    user data (i.e., to stat files, or to spawn a child process).  */
 657 void
 658 user_access (void)
 659 {
 660 #ifdef  GETLOADAVG_PRIVILEGED
 661
 662   if (!access_inited)
 663     init_access ();
 664
 665   if (current_access == user)
 666     return;
 667
 668   /* We are in "make access" mode.  This means that the effective user and
 669      group IDs are those of make (if it was installed setuid or setgid).
 670      We now want to set the effective user and group IDs to the real IDs,
 671      which are the IDs of the process that exec'd make.  */
 672
 673 #ifdef  HAVE_SETEUID
 674
 675   /* Modern systems have the seteuid/setegid calls which set only the
 676      effective IDs, which is ideal.  */
 677
 678   if (seteuid (user_uid) < 0)
 679     pfatal_with_name ("user_access: seteuid");
 680
 681 #else   /* Not HAVE_SETEUID.  */
 682
 683 #ifndef HAVE_SETREUID
 684
 685   /* System V has only the setuid/setgid calls to set user/group IDs.
 686      There is an effective ID, which can be set by setuid/setgid.
 687      It can be set (unless you are root) only to either what it already is
 688      (returned by geteuid/getegid, now in make_uid/make_gid),
 689      the real ID (return by getuid/getgid, now in user_uid/user_gid),
 690      or the saved set ID (what the effective ID was before this set-ID
 691      executable (make) was exec'd).  */
 692
 693   if (setuid (user_uid) < 0)
 694     pfatal_with_name ("user_access: setuid");
 695
 696 #else   /* HAVE_SETREUID.  */
 697
 698   /* In 4BSD, the setreuid/setregid calls set both the real and effective IDs.
 699      They may be set to themselves or each other.  So you have two alternatives
 700      at any one time.  If you use setuid/setgid, the effective will be set to
 701      the real, leaving only one alternative.  Using setreuid/setregid, however,
 702      you can toggle between your two alternatives by swapping the values in a
 703      single setreuid or setregid call.  */
 704
 705   if (setreuid (make_uid, user_uid) < 0)
 706     pfatal_with_name ("user_access: setreuid");
 707
 708 #endif  /* Not HAVE_SETREUID.  */
 709 #endif  /* HAVE_SETEUID.  */
 710
 711 #ifdef  HAVE_SETEGID
 712   if (setegid (user_gid) < 0)
 713     pfatal_with_name ("user_access: setegid");
 714 #else
 715 #ifndef HAVE_SETREGID
 716   if (setgid (user_gid) < 0)
 717     pfatal_with_name ("user_access: setgid");
 718 #else
 719   if (setregid (make_gid, user_gid) < 0)
 720     pfatal_with_name ("user_access: setregid");
 721 #endif
 722 #endif
 723
 724   current_access = user;
 725
 726   log_access (_("User access"));
 727
 728 #endif  /* GETLOADAVG_PRIVILEGED */
 729 }
 730
 731 /* Give the process appropriate permissions for access to
 732    make data (i.e., the load average).  */
 733 void
 734 make_access (void)
 735 {
 736 #ifdef  GETLOADAVG_PRIVILEGED
 737
 738   if (!access_inited)
 739     init_access ();
 740
 741   if (current_access == make)
 742     return;
 743
 744   /* See comments in user_access, above.  */
 745
 746 #ifdef  HAVE_SETEUID
 747   if (seteuid (make_uid) < 0)
 748     pfatal_with_name ("make_access: seteuid");
 749 #else
 750 #ifndef HAVE_SETREUID
 751   if (setuid (make_uid) < 0)
 752     pfatal_with_name ("make_access: setuid");
 753 #else
 754   if (setreuid (user_uid, make_uid) < 0)
 755     pfatal_with_name ("make_access: setreuid");
 756 #endif
 757 #endif
 758
 759 #ifdef  HAVE_SETEGID
 760   if (setegid (make_gid) < 0)
 761     pfatal_with_name ("make_access: setegid");
 762 #else
 763 #ifndef HAVE_SETREGID
 764   if (setgid (make_gid) < 0)
 765     pfatal_with_name ("make_access: setgid");
 766 #else
 767   if (setregid (user_gid, make_gid) < 0)
 768     pfatal_with_name ("make_access: setregid");
 769 #endif
 770 #endif
 771
 772   current_access = make;
 773
 774   log_access (_("Make access"));
 775
 776 #endif  /* GETLOADAVG_PRIVILEGED */
 777 }
 778
 779 /* Give the process appropriate permissions for a child process.
 780    This is like user_access, but you can't get back to make_access.  */
 781 void
 782 child_access (void)
 783 {
 784 #ifdef  GETLOADAVG_PRIVILEGED
 785
 786   if (!access_inited)
 787     abort ();
 788
 789   /* Set both the real and effective UID and GID to the user's.
 790      They cannot be changed back to make's.  */
 791
 792 #ifndef HAVE_SETREUID
 793   if (setuid (user_uid) < 0)
 794     pfatal_with_name ("child_access: setuid");
 795 #else
 796   if (setreuid (user_uid, user_uid) < 0)
 797     pfatal_with_name ("child_access: setreuid");
 798 #endif
 799
 800 #ifndef HAVE_SETREGID
 801   if (setgid (user_gid) < 0)
 802     pfatal_with_name ("child_access: setgid");
 803 #else
 804   if (setregid (user_gid, user_gid) < 0)
 805     pfatal_with_name ("child_access: setregid");
 806 #endif
 807
 808   log_access (_("Child access"));
 809
 810 #endif  /* GETLOADAVG_PRIVILEGED */
 811 }
 812 \f
 813 #ifdef NEED_GET_PATH_MAX
 814 unsigned int
 815 get_path_max (void)
 816 {
 817   static unsigned int value;
 818
 819   if (value == 0)
 820     {
 821       long int x = pathconf ("/", _PC_PATH_MAX);
 822       if (x > 0)
 823         value = x;
 824       else
 825         return MAXPATHLEN;
 826     }
 827
 828   return value;
 829 }
 830 #endif