arscan.c

   1 /* Library function for scanning an archive file.
   2    Copyright (C) 1987, 89, 91, 92, 93, 94 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software
  16    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  17
  18 #include "make.h"
  19
  20 #ifdef HAVE_FCNTL_H
  21 #include <fcntl.h>
  22 #else
  23 #include <sys/file.h>
  24 #endif
  25
  26 #ifndef NO_ARCHIVES
  27 \f
  28 /* SCO Unix's compiler defines both of these.  */
  29 #ifdef  M_UNIX
  30 #undef  M_XENIX
  31 #endif
  32
  33 /* On the sun386i and in System V rel 3, ar.h defines two different archive
  34    formats depending upon whether you have defined PORTAR (normal) or PORT5AR
  35    (System V Release 1).  There is no default, one or the other must be defined
  36    to have a nonzero value.  */
  37
  38 #if (!defined (PORTAR) || PORTAR == 0) && (!defined (PORT5AR) || PORT5AR == 0)
  39 #undef  PORTAR
  40 #ifdef M_XENIX
  41 /* According to Jim Sievert <jas1@rsvl.unisys.com>, for SCO XENIX defining
  42    PORTAR to 1 gets the wrong archive format, and defining it to 0 gets the
  43    right one.  */
  44 #define PORTAR 0
  45 #else
  46 #define PORTAR 1
  47 #endif
  48 #endif
  49
  50 #include <ar.h>
  51
  52 /* Cray's <ar.h> apparently defines this.  */
  53 #ifndef AR_HDR_SIZE
  54 #define AR_HDR_SIZE     (sizeof (struct ar_hdr))
  55 #endif
  56 \f
  57 /* Takes three arguments ARCHIVE, FUNCTION and ARG.
  58
  59    Open the archive named ARCHIVE, find its members one by one,
  60    and for each one call FUNCTION with the following arguments:
  61      archive file descriptor for reading the data,
  62      member name,
  63      member name might be truncated flag,
  64      member header position in file,
  65      member data position in file,
  66      member data size,
  67      member date,
  68      member uid,
  69      member gid,
  70      member protection mode,
  71      ARG.
  72
  73    The descriptor is poised to read the data of the member
  74    when FUNCTION is called.  It does not matter how much
  75    data FUNCTION reads.
  76
  77    If FUNCTION returns nonzero, we immediately return
  78    what FUNCTION returned.
  79
  80    Returns -1 if archive does not exist,
  81    Returns -2 if archive has invalid format.
  82    Returns 0 if have scanned successfully.  */
  83
  84 long int
  85 ar_scan (archive, function, arg)
  86      char *archive;
  87      long int (*function) ();
  88      long int arg;
  89 {
  90 #ifdef AIAMAG
  91   FL_HDR fl_header;
  92 #else
  93   int long_name = 0;
  94 #endif
  95   char *namemap = 0;
  96   register int desc = open (archive, O_RDONLY, 0);
  97   if (desc < 0)
  98     return -1;
  99 #ifdef SARMAG
 100   {
 101     char buf[SARMAG];
 102     register int nread = read (desc, buf, SARMAG);
 103     if (nread != SARMAG || bcmp (buf, ARMAG, SARMAG))
 104       {
 105         (void) close (desc);
 106         return -2;
 107       }
 108   }
 109 #else
 110 #ifdef AIAMAG
 111   {
 112     register int nread = read (desc, (char *) &fl_header, FL_HSZ);
 113     if (nread != FL_HSZ || bcmp (fl_header.fl_magic, AIAMAG, SAIAMAG))
 114       {
 115         (void) close (desc);
 116         return -2;
 117       }
 118   }
 119 #else
 120   {
 121 #ifndef M_XENIX
 122     int buf;
 123 #else
 124     unsigned short int buf;
 125 #endif
 126     register int nread = read(desc, &buf, sizeof (buf));
 127     if (nread != sizeof (buf) || buf != ARMAG)
 128       {
 129         (void) close (desc);
 130         return -2;
 131       }
 132   }
 133 #endif
 134 #endif
 135
 136   /* Now find the members one by one.  */
 137   {
 138 #ifdef SARMAG
 139     register long int member_offset = SARMAG;
 140 #else
 141 #ifdef AIAMAG
 142     long int member_offset;
 143     long int last_member_offset;
 144
 145     sscanf (fl_header.fl_fstmoff, "%12ld", &member_offset);
 146     sscanf (fl_header.fl_lstmoff, "%12ld", &last_member_offset);
 147 #else
 148 #ifndef M_XENIX
 149     register long int member_offset = sizeof (int);
 150 #else   /* Xenix.  */
 151     register long int member_offset = sizeof (unsigned short int);
 152 #endif  /* Not Xenix.  */
 153 #endif
 154 #endif
 155
 156     while (1)
 157       {
 158         register int nread;
 159         struct ar_hdr member_header;
 160 #ifdef AIAMAG
 161         char name[256];
 162         int name_len;
 163         long int dateval;
 164         int uidval, gidval;
 165         long int data_offset;
 166 #else
 167         char namebuf[sizeof member_header.ar_name + 1];
 168         char *name;
 169         int is_namemap;         /* Nonzero if this entry maps long names.  */
 170 #endif
 171         long int eltsize;
 172         int eltmode;
 173         long int fnval;
 174
 175         if (lseek (desc, member_offset, 0) < 0)
 176           {
 177             (void) close (desc);
 178             return -2;
 179           }
 180
 181 #ifdef AIAMAG
 182 #define AR_MEMHDR       (AR_HDR_SIZE - sizeof (member_header._ar_name))
 183         nread = read (desc, (char *) &member_header, AR_MEMHDR);
 184
 185         if (nread != AR_MEMHDR)
 186           {
 187             (void) close (desc);
 188             return -2;
 189           }
 190
 191         sscanf (member_header.ar_namlen, "%4d", &name_len);
 192         nread = read (desc, name, name_len);
 193
 194         if (nread != name_len)
 195           {
 196             (void) close (desc);
 197             return -2;
 198           }
 199
 200         name[name_len] = 0;
 201
 202         sscanf (member_header.ar_date, "%12ld", &dateval);
 203         sscanf (member_header.ar_uid, "%12d", &uidval);
 204         sscanf (member_header.ar_gid, "%12d", &gidval);
 205         sscanf (member_header.ar_mode, "%12o", &eltmode);
 206         sscanf (member_header.ar_size, "%12ld", &eltsize);
 207
 208         if ((data_offset = member_offset + AR_MEMHDR + name_len + 2) % 2)
 209             ++data_offset;
 210
 211         fnval =
 212           (*function) (desc, name, 0,
 213                        member_offset, data_offset, eltsize,
 214                        dateval, uidval, gidval,
 215                        eltmode, arg);
 216
 217 #else   /* Not AIAMAG.  */
 218         nread = read (desc, (char *) &member_header, AR_HDR_SIZE);
 219         if (nread == 0)
 220           /* No data left means end of file; that is OK.  */
 221           break;
 222
 223         if (nread != AR_HDR_SIZE
 224 #ifdef ARFMAG
 225             || bcmp (member_header.ar_fmag, ARFMAG, 2)
 226 #endif
 227             )
 228           {
 229             (void) close (desc);
 230             return -2;
 231           }
 232
 233         name = namebuf;
 234         bcopy (member_header.ar_name, name, sizeof member_header.ar_name);
 235         {
 236           register char *p = name + sizeof member_header.ar_name;
 237           do
 238             *p = '\0';
 239           while (p > name && *--p == ' ');
 240
 241 #ifndef AIAMAG
 242           /* If the member name is "//" or "ARFILENAMES/" this may be
 243              a list of file name mappings.  The maximum file name
 244              length supported by the standard archive format is 14
 245              characters.  This member will actually always be the
 246              first or second entry in the archive, but we don't check
 247              that.  */
 248           is_namemap = (!strcmp (name, "//")
 249                         || !strcmp (name, "ARFILENAMES/"));
 250 #endif  /* Not AIAMAG. */
 251           /* On some systems, there is a slash after each member name.  */
 252           if (*p == '/')
 253             *p = '\0';
 254
 255 #ifndef AIAMAG
 256           /* If the member name starts with a space or a slash, this
 257              is an index into the file name mappings (used by GNU ar).
 258              Otherwise if the member name looks like #1/NUMBER the
 259              real member name appears in the element data (used by
 260              4.4BSD).  */
 261           if (! is_namemap
 262               && (name[0] == ' ' || name[0] == '/')
 263               && namemap != 0)
 264             {
 265               name = namemap + atoi (name + 1);
 266               long_name = 1;
 267             }
 268           else if (name[0] == '#'
 269                    && name[1] == '1'
 270                    && name[2] == '/')
 271             {
 272               int namesize = atoi (name + 3);
 273
 274               name = (char *) alloca (namesize + 1);
 275               nread = read (desc, name, namesize);
 276               if (nread != namesize)
 277                 {
 278                   close (desc);
 279                   return -2;
 280                 }
 281               name[namesize] = '\0';
 282
 283               long_name = 1;
 284             }
 285 #endif /* Not AIAMAG. */
 286         }
 287
 288 #ifndef M_XENIX
 289         sscanf (member_header.ar_mode, "%o", &eltmode);
 290         eltsize = atol (member_header.ar_size);
 291 #else   /* Xenix.  */
 292         eltmode = (unsigned short int) member_header.ar_mode;
 293         eltsize = member_header.ar_size;
 294 #endif  /* Not Xenix.  */
 295
 296         fnval =
 297           (*function) (desc, name, ! long_name, member_offset,
 298                        member_offset + AR_HDR_SIZE, eltsize,
 299 #ifndef M_XENIX
 300                        atol (member_header.ar_date),
 301                        atoi (member_header.ar_uid),
 302                        atoi (member_header.ar_gid),
 303 #else   /* Xenix.  */
 304                        member_header.ar_date,
 305                        member_header.ar_uid,
 306                        member_header.ar_gid,
 307 #endif  /* Not Xenix.  */
 308                        eltmode, arg);
 309
 310 #endif  /* AIAMAG.  */
 311
 312         if (fnval)
 313           {
 314             (void) close (desc);
 315             return fnval;
 316           }
 317
 318 #ifdef AIAMAG
 319         if (member_offset == last_member_offset)
 320           /* End of the chain.  */
 321           break;
 322
 323         sscanf (member_header.ar_nxtmem, "%12ld", &member_offset);
 324
 325         if (lseek (desc, member_offset, 0) != member_offset)
 326           {
 327             (void) close (desc);
 328             return -2;
 329           }
 330 #else
 331
 332         /* If this member maps archive names, we must read it in.  The
 333            name map will always precede any members whose names must
 334            be mapped.  */
 335         if (is_namemap)
 336           {
 337             char *clear;
 338             char *limit;
 339
 340             namemap = (char *) alloca (eltsize);
 341             nread = read (desc, namemap, eltsize);
 342             if (nread != eltsize)
 343               {
 344                 (void) close (desc);
 345                 return -2;
 346               }
 347
 348             /* The names are separated by newlines.  Some formats have
 349                a trailing slash.  Null terminate the strings for
 350                convenience.  */
 351             limit = namemap + eltsize;
 352             for (clear = namemap; clear < limit; clear++)
 353               {
 354                 if (*clear == '\n')
 355                   {
 356                     *clear = '\0';
 357                     if (clear[-1] == '/')
 358                       clear[-1] = '\0';
 359                   }
 360               }
 361
 362             is_namemap = 0;
 363           }
 364
 365         member_offset += AR_HDR_SIZE + eltsize;
 366         if (member_offset % 2 != 0)
 367           member_offset++;
 368 #endif
 369       }
 370   }
 371
 372   close (desc);
 373   return 0;
 374 }
 375 \f
 376 /* Return nonzero iff NAME matches MEM.
 377    If TRUNCATED is nonzero, MEM may be truncated to
 378    sizeof (struct ar_hdr.ar_name) - 1.  */
 379
 380 int
 381 ar_name_equal (name, mem, truncated)
 382      char *name, *mem;
 383      int truncated;
 384 {
 385   char *p;
 386
 387   p = rindex (name, '/');
 388   if (p != 0)
 389     name = p + 1;
 390
 391   /* We no longer use this kludge, since we
 392      now support long archive member names.  */
 393
 394 #if 0 && !defined (AIAMAG) && !defined (APOLLO)
 395
 396   {
 397     /* `reallylongname.o' matches `reallylongnam.o'.
 398        If member names have a trailing slash, that's `reallylongna.o'.  */
 399
 400     struct ar_hdr h;
 401     unsigned int max = sizeof (h.ar_name);
 402     unsigned int namelen, memlen;
 403
 404     if (strncmp (name, mem, max - 3))
 405       return 0;
 406
 407     namelen = strlen (name);
 408     memlen = strlen (mem);
 409
 410     if (namelen > memlen && memlen >= max - 1
 411         && name[namelen - 2] == '.' && name[namelen - 1] == 'o'
 412         && mem[memlen - 2] == '.' && mem[memlen - 1] == 'o')
 413       return 1;
 414
 415     if (namelen != memlen)
 416       return 0;
 417
 418     return (namelen < max - 3 || !strcmp (name + max - 3, mem + max - 3));
 419   }
 420
 421 #else   /* AIX or APOLLO.  */
 422
 423   if (truncated)
 424     {
 425 #ifdef AIAMAG
 426       /* TRUNCATED should never be set on this system.  */
 427       abort ();
 428 #else
 429       struct ar_hdr hdr;
 430       return !strncmp (name, mem,
 431                        sizeof (hdr.ar_name) -
 432 #if !defined (__hpux) && !defined (cray)
 433                        1
 434 #else
 435                        2
 436 #endif /* !__hpux && !cray */
 437                        );
 438 #endif
 439     }
 440
 441   return !strcmp (name, mem);
 442
 443 #endif
 444 }
 445 \f
 446 /* ARGSUSED */
 447 static long int
 448 ar_member_pos (desc, mem, truncated,
 449                hdrpos, datapos, size, date, uid, gid, mode, name)
 450      int desc;
 451      char *mem;
 452      int truncated;
 453      long int hdrpos, datapos, size, date;
 454      int uid, gid, mode;
 455      char *name;
 456 {
 457   if (!ar_name_equal (name, mem, truncated))
 458     return 0;
 459   return hdrpos;
 460 }
 461
 462 /* Set date of member MEMNAME in archive ARNAME to current time.
 463    Returns 0 if successful,
 464    -1 if file ARNAME does not exist,
 465    -2 if not a valid archive,
 466    -3 if other random system call error (including file read-only),
 467    1 if valid but member MEMNAME does not exist.  */
 468
 469 int
 470 ar_member_touch (arname, memname)
 471      char *arname, *memname;
 472 {
 473   register long int pos = ar_scan (arname, ar_member_pos, (long int) memname);
 474   register int fd;
 475   struct ar_hdr ar_hdr;
 476   register int i;
 477   struct stat statbuf;
 478
 479   if (pos < 0)
 480     return (int) pos;
 481   if (!pos)
 482     return 1;
 483
 484   fd = open (arname, O_RDWR, 0666);
 485   if (fd < 0)
 486     return -3;
 487   /* Read in this member's header */
 488   if (lseek (fd, pos, 0) < 0)
 489     goto lose;
 490   if (AR_HDR_SIZE != read (fd, (char *) &ar_hdr, AR_HDR_SIZE))
 491     goto lose;
 492   /* Write back the header, thus touching the archive file.  */
 493   if (lseek (fd, pos, 0) < 0)
 494     goto lose;
 495   if (AR_HDR_SIZE != write (fd, (char *) &ar_hdr, AR_HDR_SIZE))
 496     goto lose;
 497   /* The file's mtime is the time we we want.  */
 498 #ifdef EINTR
 499   while (fstat (fd, &statbuf) < 0 && errno == EINTR);
 500 #else
 501   fstat (fd, &statbuf);
 502 #endif
 503 #if defined(ARFMAG) || defined(AIAMAG)
 504   /* Advance member's time to that time */
 505   for (i = 0; i < sizeof ar_hdr.ar_date; i++)
 506     ar_hdr.ar_date[i] = ' ';
 507   sprintf (ar_hdr.ar_date, "%ld", (long int) statbuf.st_mtime);
 508 #ifdef AIAMAG
 509   ar_hdr.ar_date[strlen(ar_hdr.ar_date)] = ' ';
 510 #endif
 511 #else
 512   ar_hdr.ar_date = statbuf.st_mtime;
 513 #endif
 514   /* Write back this member's header */
 515   if (lseek (fd, pos, 0) < 0)
 516     goto lose;
 517   if (AR_HDR_SIZE != write (fd, (char *) &ar_hdr, AR_HDR_SIZE))
 518     goto lose;
 519   close (fd);
 520   return 0;
 521
 522  lose:
 523   i = errno;
 524   close (fd);
 525   errno = i;
 526   return -3;
 527 }
 528 \f
 529 #ifdef TEST
 530
 531 long int
 532 describe_member (desc, name, truncated,
 533                  hdrpos, datapos, size, date, uid, gid, mode)
 534      int desc;
 535      char *name;
 536      int truncated;
 537      long int hdrpos, datapos, size, date;
 538      int uid, gid, mode;
 539 {
 540   extern char *ctime ();
 541
 542   printf ("Member `%s'%s: %ld bytes at %ld (%ld).\n",
 543           name, truncated ? " (name might be truncated)" : "",
 544           size, hdrpos, datapos);
 545   printf ("  Date %s", ctime (&date));
 546   printf ("  uid = %d, gid = %d, mode = 0%o.\n", uid, gid, mode);
 547
 548   return 0;
 549 }
 550
 551 main (argc, argv)
 552      int argc;
 553      char **argv;
 554 {
 555   ar_scan (argv[1], describe_member);
 556   return 0;
 557 }
 558
 559 #endif  /* TEST.  */
 560 \f
 561 #endif  /* NO_ARCHIVES.  */