Dogcows Code - chaz/tar/blob - src/xheader.c

   1 /* POSIX extended headers for tar.
   2
   3    Copyright (C) 2003, 2004, 2005, 2006, 2007, 2009 Free Software Foundation, Inc.
   4
   5    This program is free software; you can redistribute it and/or modify it
   6    under the terms of the GNU General Public License as published by the
   7    Free Software Foundation; either version 3, or (at your option) any later
   8    version.
   9
  10    This program is distributed in the hope that it will be useful, but
  11    WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
  13    Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License along
  16    with this program; if not, write to the Free Software Foundation, Inc.,
  17    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  18
  19 #include <system.h>
  20
  21 #include <fnmatch.h>
  22 #include <hash.h>
  23 #include <inttostr.h>
  24 #include <quotearg.h>
  25
  26 #include "common.h"
  27
  28 static bool xheader_protected_pattern_p (char const *pattern);
  29 static bool xheader_protected_keyword_p (char const *keyword);
  30 static void xheader_set_single_keyword (char *) __attribute__ ((noreturn));
  31
  32 /* Used by xheader_finish() */
  33 static void code_string (char const *string, char const *keyword,
  34                          struct xheader *xhdr);
  35
  36 /* Number of global headers written so far. */
  37 static size_t global_header_count;
  38 /* FIXME: Possibly it should be reset after changing the volume.
  39    POSIX %n specification says that it is expanded to the sequence
  40    number of current global header in *the* archive. However, for
  41    multi-volume archives this will yield duplicate header names
  42    in different volumes, which I'd like to avoid. The best way
  43    to solve this would be to use per-archive header count as required
  44    by POSIX *and* set globexthdr.name to, say,
  45    $TMPDIR/GlobalHead.%p.$NUMVOLUME.%n.
  46
  47    However it should wait until buffer.c is finally rewritten */
  48
  49 \f
  50 /* Interface functions to obstacks */
  51
  52 static void
  53 x_obstack_grow (struct xheader *xhdr, const char *ptr, size_t length)
  54 {
  55   obstack_grow (xhdr->stk, ptr, length);
  56   xhdr->size += length;
  57 }
  58
  59 static void
  60 x_obstack_1grow (struct xheader *xhdr, char c)
  61 {
  62   obstack_1grow (xhdr->stk, c);
  63   xhdr->size++;
  64 }
  65
  66 static void
  67 x_obstack_blank (struct xheader *xhdr, size_t length)
  68 {
  69   obstack_blank (xhdr->stk, length);
  70   xhdr->size += length;
  71 }
  72
  73 \f
  74 /* Keyword options */
  75
  76 struct keyword_list
  77 {
  78   struct keyword_list *next;
  79   char *pattern;
  80   char *value;
  81 };
  82
  83
  84 /* List of keyword patterns set by delete= option */
  85 static struct keyword_list *keyword_pattern_list;
  86
  87 /* List of keyword/value pairs set by `keyword=value' option */
  88 static struct keyword_list *keyword_global_override_list;
  89
  90 /* List of keyword/value pairs set by `keyword:=value' option */
  91 static struct keyword_list *keyword_override_list;
  92
  93 /* List of keyword/value pairs decoded from the last 'g' type header */
  94 static struct keyword_list *global_header_override_list;
  95
  96 /* Template for the name field of an 'x' type header */
  97 static char *exthdr_name;
  98
  99 /* Template for the name field of a 'g' type header */
 100 static char *globexthdr_name;
 101
 102 bool
 103 xheader_keyword_deleted_p (const char *kw)
 104 {
 105   struct keyword_list *kp;
 106
 107   for (kp = keyword_pattern_list; kp; kp = kp->next)
 108     if (fnmatch (kp->pattern, kw, 0) == 0)
 109       return true;
 110   return false;
 111 }
 112
 113 static bool
 114 xheader_keyword_override_p (const char *keyword)
 115 {
 116   struct keyword_list *kp;
 117
 118   for (kp = keyword_override_list; kp; kp = kp->next)
 119     if (strcmp (kp->pattern, keyword) == 0)
 120       return true;
 121   return false;
 122 }
 123
 124 static void
 125 xheader_list_append (struct keyword_list **root, char const *kw,
 126                      char const *value)
 127 {
 128   struct keyword_list *kp = xmalloc (sizeof *kp);
 129   kp->pattern = xstrdup (kw);
 130   kp->value = value ? xstrdup (value) : NULL;
 131   kp->next = *root;
 132   *root = kp;
 133 }
 134
 135 static void
 136 xheader_list_destroy (struct keyword_list **root)
 137 {
 138   if (root)
 139     {
 140       struct keyword_list *kw = *root;
 141       while (kw)
 142         {
 143           struct keyword_list *next = kw->next;
 144           free (kw->pattern);
 145           free (kw->value);
 146           free (kw);
 147           kw = next;
 148         }
 149       *root = NULL;
 150     }
 151 }
 152
 153 static void
 154 xheader_set_single_keyword (char *kw)
 155 {
 156   USAGE_ERROR ((0, 0, _("Keyword %s is unknown or not yet implemented"), kw));
 157 }
 158
 159 static void
 160 xheader_set_keyword_equal (char *kw, char *eq)
 161 {
 162   bool global = true;
 163   char *p = eq;
 164
 165   if (eq[-1] == ':')
 166     {
 167       p--;
 168       global = false;
 169     }
 170
 171   while (p > kw && isspace ((unsigned char) *p))
 172     p--;
 173
 174   *p = 0;
 175
 176   for (p = eq + 1; *p && isspace ((unsigned char) *p); p++)
 177     ;
 178
 179   if (strcmp (kw, "delete") == 0)
 180     {
 181       if (xheader_protected_pattern_p (p))
 182         USAGE_ERROR ((0, 0, _("Pattern %s cannot be used"), quote (p)));
 183       xheader_list_append (&keyword_pattern_list, p, NULL);
 184     }
 185   else if (strcmp (kw, "exthdr.name") == 0)
 186     assign_string (&exthdr_name, p);
 187   else if (strcmp (kw, "globexthdr.name") == 0)
 188     assign_string (&globexthdr_name, p);
 189   else
 190     {
 191       if (xheader_protected_keyword_p (kw))
 192         USAGE_ERROR ((0, 0, _("Keyword %s cannot be overridden"), kw));
 193       if (global)
 194         xheader_list_append (&keyword_global_override_list, kw, p);
 195       else
 196         xheader_list_append (&keyword_override_list, kw, p);
 197     }
 198 }
 199
 200 void
 201 xheader_set_option (char *string)
 202 {
 203   char *token;
 204   for (token = strtok (string, ","); token; token = strtok (NULL, ","))
 205     {
 206       char *p = strchr (token, '=');
 207       if (!p)
 208         xheader_set_single_keyword (token);
 209       else
 210         xheader_set_keyword_equal (token, p);
 211     }
 212 }
 213
 214 /*
 215     string Includes:          Replaced By:
 216      %d                       The directory name of the file,
 217                               equivalent to the result of the
 218                               dirname utility on the translated
 219                               file name.
 220      %f                       The filename of the file, equivalent
 221                               to the result of the basename
 222                               utility on the translated file name.
 223      %p                       The process ID of the pax process.
 224      %n                       The value of the 3rd argument.
 225      %%                       A '%' character. */
 226
 227 char *
 228 xheader_format_name (struct tar_stat_info *st, const char *fmt, size_t n)
 229 {
 230   char *buf;
 231   size_t len = strlen (fmt);
 232   char *q;
 233   const char *p;
 234   char *dirp = NULL;
 235   char *dir = NULL;
 236   char *base = NULL;
 237   char pidbuf[UINTMAX_STRSIZE_BOUND];
 238   char const *pptr;
 239   char nbuf[UINTMAX_STRSIZE_BOUND];
 240   char const *nptr = NULL;
 241
 242   for (p = fmt; *p && (p = strchr (p, '%')); )
 243     {
 244       switch (p[1])
 245         {
 246         case '%':
 247           len--;
 248           break;
 249
 250         case 'd':
 251           if (st)
 252             {
 253               if (!dirp)
 254                 dirp = dir_name (st->orig_file_name);
 255               dir = safer_name_suffix (dirp, false, absolute_names_option);
 256               len += strlen (dir) - 2;
 257             }
 258           break;
 259
 260         case 'f':
 261           if (st)
 262             {
 263               base = last_component (st->orig_file_name);
 264               len += strlen (base) - 2;
 265             }
 266           break;
 267
 268         case 'p':
 269           pptr = umaxtostr (getpid (), pidbuf);
 270           len += pidbuf + sizeof pidbuf - 1 - pptr - 2;
 271           break;
 272
 273         case 'n':
 274           nptr = umaxtostr (n, nbuf);
 275           len += nbuf + sizeof nbuf - 1 - nptr - 2;
 276           break;
 277         }
 278       p++;
 279     }
 280
 281   buf = xmalloc (len + 1);
 282   for (q = buf, p = fmt; *p; )
 283     {
 284       if (*p == '%')
 285         {
 286           switch (p[1])
 287             {
 288             case '%':
 289               *q++ = *p++;
 290               p++;
 291               break;
 292
 293             case 'd':
 294               if (dir)
 295                 q = stpcpy (q, dir);
 296               p += 2;
 297               break;
 298
 299             case 'f':
 300               if (base)
 301                 q = stpcpy (q, base);
 302               p += 2;
 303               break;
 304
 305             case 'p':
 306               q = stpcpy (q, pptr);
 307               p += 2;
 308               break;
 309
 310             case 'n':
 311               if (nptr)
 312                 {
 313                   q = stpcpy (q, nptr);
 314                   p += 2;
 315                   break;
 316                 }
 317               /* else fall through */
 318
 319             default:
 320               *q++ = *p++;
 321               if (*p)
 322                 *q++ = *p++;
 323             }
 324         }
 325       else
 326         *q++ = *p++;
 327     }
 328
 329   free (dirp);
 330
 331   /* Do not allow it to end in a slash */
 332   while (q > buf && ISSLASH (q[-1]))
 333     q--;
 334   *q = 0;
 335   return buf;
 336 }
 337
 338 char *
 339 xheader_xhdr_name (struct tar_stat_info *st)
 340 {
 341   if (!exthdr_name)
 342     assign_string (&exthdr_name, "%d/PaxHeaders.%p/%f");
 343   return xheader_format_name (st, exthdr_name, 0);
 344 }
 345
 346 #define GLOBAL_HEADER_TEMPLATE "/GlobalHead.%p.%n"
 347
 348 char *
 349 xheader_ghdr_name (void)
 350 {
 351   if (!globexthdr_name)
 352     {
 353       size_t len;
 354       const char *tmp = getenv ("TMPDIR");
 355       if (!tmp)
 356         tmp = "/tmp";
 357       len = strlen (tmp) + sizeof (GLOBAL_HEADER_TEMPLATE); /* Includes nul */
 358       globexthdr_name = xmalloc (len);
 359       strcpy(globexthdr_name, tmp);
 360       strcat(globexthdr_name, GLOBAL_HEADER_TEMPLATE);
 361     }
 362
 363   return xheader_format_name (NULL, globexthdr_name, global_header_count + 1);
 364 }
 365
 366 void
 367 xheader_write (char type, char *name, struct xheader *xhdr)
 368 {
 369   union block *header;
 370   size_t size;
 371   char *p;
 372
 373   size = xhdr->size;
 374   header = start_private_header (name, size);
 375   header->header.typeflag = type;
 376
 377   simple_finish_header (header);
 378
 379   p = xhdr->buffer;
 380
 381   do
 382     {
 383       size_t len;
 384
 385       header = find_next_block ();
 386       len = BLOCKSIZE;
 387       if (len > size)
 388         len = size;
 389       memcpy (header->buffer, p, len);
 390       if (len < BLOCKSIZE)
 391         memset (header->buffer + len, 0, BLOCKSIZE - len);
 392       p += len;
 393       size -= len;
 394       set_next_block_after (header);
 395     }
 396   while (size > 0);
 397   xheader_destroy (xhdr);
 398
 399   if (type == XGLTYPE)
 400     global_header_count++;
 401 }
 402
 403 void
 404 xheader_write_global (struct xheader *xhdr)
 405 {
 406   char *name;
 407   struct keyword_list *kp;
 408
 409   if (!keyword_global_override_list)
 410     return;
 411
 412   xheader_init (xhdr);
 413   for (kp = keyword_global_override_list; kp; kp = kp->next)
 414     code_string (kp->value, kp->pattern, xhdr);
 415   xheader_finish (xhdr);
 416   xheader_write (XGLTYPE, name = xheader_ghdr_name (), xhdr);
 417   free (name);
 418 }
 419
 420 \f
 421 /* General Interface */
 422
 423 struct xhdr_tab
 424 {
 425   char const *keyword;
 426   void (*coder) (struct tar_stat_info const *, char const *,
 427                  struct xheader *, void const *data);
 428   void (*decoder) (struct tar_stat_info *, char const *, char const *, size_t);
 429   bool protect;
 430 };
 431
 432 /* This declaration must be extern, because ISO C99 section 6.9.2
 433    prohibits a tentative definition that has both internal linkage and
 434    incomplete type.  If we made it static, we'd have to declare its
 435    size which would be a maintenance pain; if we put its initializer
 436    here, we'd need a boatload of forward declarations, which would be
 437    even more of a pain.  */
 438 extern struct xhdr_tab const xhdr_tab[];
 439
 440 static struct xhdr_tab const *
 441 locate_handler (char const *keyword)
 442 {
 443   struct xhdr_tab const *p;
 444
 445   for (p = xhdr_tab; p->keyword; p++)
 446     if (strcmp (p->keyword, keyword) == 0)
 447       return p;
 448   return NULL;
 449 }
 450
 451 static bool
 452 xheader_protected_pattern_p (const char *pattern)
 453 {
 454   struct xhdr_tab const *p;
 455
 456   for (p = xhdr_tab; p->keyword; p++)
 457     if (p->protect && fnmatch (pattern, p->keyword, 0) == 0)
 458       return true;
 459   return false;
 460 }
 461
 462 static bool
 463 xheader_protected_keyword_p (const char *keyword)
 464 {
 465   struct xhdr_tab const *p;
 466
 467   for (p = xhdr_tab; p->keyword; p++)
 468     if (p->protect && strcmp (p->keyword, keyword) == 0)
 469       return true;
 470   return false;
 471 }
 472
 473 /* Decode a single extended header record, advancing *PTR to the next record.
 474    Return true on success, false otherwise.  */
 475 static bool
 476 decode_record (struct xheader *xhdr,
 477                char **ptr,
 478                void (*handler) (void *, char const *, char const *, size_t),
 479                void *data)
 480 {
 481   char *start = *ptr;
 482   char *p = start;
 483   uintmax_t u;
 484   size_t len;
 485   char *len_lim;
 486   char const *keyword;
 487   char *nextp;
 488   size_t len_max = xhdr->buffer + xhdr->size - start;
 489
 490   while (*p == ' ' || *p == '\t')
 491     p++;
 492
 493   if (! ISDIGIT (*p))
 494     {
 495       if (*p)
 496         ERROR ((0, 0, _("Malformed extended header: missing length")));
 497       return false;
 498     }
 499
 500   errno = 0;
 501   len = u = strtoumax (p, &len_lim, 10);
 502   if (len != u || errno == ERANGE)
 503     {
 504       ERROR ((0, 0, _("Extended header length is out of allowed range")));
 505       return false;
 506     }
 507
 508   if (len_max < len)
 509     {
 510       int len_len = len_lim - p;
 511       ERROR ((0, 0, _("Extended header length %*s is out of range"),
 512               len_len, p));
 513       return false;
 514     }
 515
 516   nextp = start + len;
 517
 518   for (p = len_lim; *p == ' ' || *p == '\t'; p++)
 519     continue;
 520   if (p == len_lim)
 521     {
 522       ERROR ((0, 0,
 523               _("Malformed extended header: missing blank after length")));
 524       return false;
 525     }
 526
 527   keyword = p;
 528   p = strchr (p, '=');
 529   if (! (p && p < nextp))
 530     {
 531       ERROR ((0, 0, _("Malformed extended header: missing equal sign")));
 532       return false;
 533     }
 534
 535   if (nextp[-1] != '\n')
 536     {
 537       ERROR ((0, 0, _("Malformed extended header: missing newline")));
 538       return false;
 539     }
 540
 541   *p = nextp[-1] = '\0';
 542   handler (data, keyword, p + 1, nextp - p - 2); /* '=' + trailing '\n' */
 543   *p = '=';
 544   nextp[-1] = '\n';
 545   *ptr = nextp;
 546   return true;
 547 }
 548
 549 static void
 550 run_override_list (struct keyword_list *kp, struct tar_stat_info *st)
 551 {
 552   for (; kp; kp = kp->next)
 553     {
 554       struct xhdr_tab const *t = locate_handler (kp->pattern);
 555       if (t)
 556         t->decoder (st, t->keyword, kp->value, strlen (kp->value));
 557     }
 558 }
 559
 560 static void
 561 decx (void *data, char const *keyword, char const *value, size_t size)
 562 {
 563   struct xhdr_tab const *t;
 564   struct tar_stat_info *st = data;
 565
 566   if (xheader_keyword_deleted_p (keyword)
 567       || xheader_keyword_override_p (keyword))
 568     return;
 569
 570   t = locate_handler (keyword);
 571   if (t)
 572     t->decoder (st, keyword, value, size);
 573   else
 574     WARNOPT (WARN_UNKNOWN_KEYWORD,
 575              (0, 0, _("Ignoring unknown extended header keyword `%s'"),
 576               keyword));
 577 }
 578
 579 void
 580 xheader_decode (struct tar_stat_info *st)
 581 {
 582   run_override_list (keyword_global_override_list, st);
 583   run_override_list (global_header_override_list, st);
 584
 585   if (st->xhdr.size)
 586     {
 587       char *p = st->xhdr.buffer + BLOCKSIZE;
 588       while (decode_record (&st->xhdr, &p, decx, st))
 589         continue;
 590     }
 591   run_override_list (keyword_override_list, st);
 592 }
 593
 594 static void
 595 decg (void *data, char const *keyword, char const *value,
 596       size_t size __attribute__((unused)))
 597 {
 598   struct keyword_list **kwl = data;
 599   xheader_list_append (kwl, keyword, value);
 600 }
 601
 602 void
 603 xheader_decode_global (struct xheader *xhdr)
 604 {
 605   if (xhdr->size)
 606     {
 607       char *p = xhdr->buffer + BLOCKSIZE;
 608
 609       xheader_list_destroy (&global_header_override_list);
 610       while (decode_record (xhdr, &p, decg, &global_header_override_list))
 611         continue;
 612     }
 613 }
 614
 615 void
 616 xheader_init (struct xheader *xhdr)
 617 {
 618   if (!xhdr->stk)
 619     {
 620       xhdr->stk = xmalloc (sizeof *xhdr->stk);
 621       obstack_init (xhdr->stk);
 622     }
 623 }
 624
 625 void
 626 xheader_store (char const *keyword, struct tar_stat_info *st,
 627                void const *data)
 628 {
 629   struct xhdr_tab const *t;
 630
 631   if (st->xhdr.buffer)
 632     return;
 633   t = locate_handler (keyword);
 634   if (!t || !t->coder)
 635     return;
 636   if (xheader_keyword_deleted_p (keyword)
 637       || xheader_keyword_override_p (keyword))
 638     return;
 639   xheader_init (&st->xhdr);
 640   t->coder (st, keyword, &st->xhdr, data);
 641 }
 642
 643 void
 644 xheader_read (struct xheader *xhdr, union block *p, size_t size)
 645 {
 646   size_t j = 0;
 647
 648   xheader_init (xhdr);
 649   size += BLOCKSIZE;
 650   xhdr->size = size;
 651   xhdr->buffer = xmalloc (size + 1);
 652   xhdr->buffer[size] = '\0';
 653
 654   do
 655     {
 656       size_t len = size;
 657
 658       if (len > BLOCKSIZE)
 659         len = BLOCKSIZE;
 660
 661       memcpy (&xhdr->buffer[j], p->buffer, len);
 662       set_next_block_after (p);
 663
 664       p = find_next_block ();
 665
 666       j += len;
 667       size -= len;
 668     }
 669   while (size > 0);
 670 }
 671
 672 static void
 673 xheader_print_n (struct xheader *xhdr, char const *keyword,
 674                  char const *value, size_t vsize)
 675 {
 676   size_t len = strlen (keyword) + vsize + 3; /* ' ' + '=' + '\n' */
 677   size_t p;
 678   size_t n = 0;
 679   char nbuf[UINTMAX_STRSIZE_BOUND];
 680   char const *np;
 681
 682   do
 683     {
 684       p = n;
 685       np = umaxtostr (len + p, nbuf);
 686       n = nbuf + sizeof nbuf - 1 - np;
 687     }
 688   while (n != p);
 689
 690   x_obstack_grow (xhdr, np, n);
 691   x_obstack_1grow (xhdr, ' ');
 692   x_obstack_grow (xhdr, keyword, strlen (keyword));
 693   x_obstack_1grow (xhdr, '=');
 694   x_obstack_grow (xhdr, value, vsize);
 695   x_obstack_1grow (xhdr, '\n');
 696 }
 697
 698 static void
 699 xheader_print (struct xheader *xhdr, char const *keyword, char const *value)
 700 {
 701   xheader_print_n (xhdr, keyword, value, strlen (value));
 702 }
 703
 704 void
 705 xheader_finish (struct xheader *xhdr)
 706 {
 707   struct keyword_list *kp;
 708
 709   for (kp = keyword_override_list; kp; kp = kp->next)
 710     code_string (kp->value, kp->pattern, xhdr);
 711
 712   xhdr->buffer = obstack_finish (xhdr->stk);
 713 }
 714
 715 void
 716 xheader_destroy (struct xheader *xhdr)
 717 {
 718   if (xhdr->stk)
 719     {
 720       obstack_free (xhdr->stk, NULL);
 721       free (xhdr->stk);
 722       xhdr->stk = NULL;
 723     }
 724   else
 725     free (xhdr->buffer);
 726   xhdr->buffer = 0;
 727   xhdr->size = 0;
 728 }
 729
 730 \f
 731 /* Buildable strings */
 732
 733 void
 734 xheader_string_begin (struct xheader *xhdr)
 735 {
 736   xhdr->string_length = 0;
 737 }
 738
 739 void
 740 xheader_string_add (struct xheader *xhdr, char const *s)
 741 {
 742   if (xhdr->buffer)
 743     return;
 744   xheader_init (xhdr);
 745   xhdr->string_length += strlen (s);
 746   x_obstack_grow (xhdr, s, strlen (s));
 747 }
 748
 749 bool
 750 xheader_string_end (struct xheader *xhdr, char const *keyword)
 751 {
 752   uintmax_t len;
 753   uintmax_t p;
 754   uintmax_t n = 0;
 755   size_t size;
 756   char nbuf[UINTMAX_STRSIZE_BOUND];
 757   char const *np;
 758   char *cp;
 759
 760   if (xhdr->buffer)
 761     return false;
 762   xheader_init (xhdr);
 763
 764   len = strlen (keyword) + xhdr->string_length + 3; /* ' ' + '=' + '\n' */
 765
 766   do
 767     {
 768       p = n;
 769       np = umaxtostr (len + p, nbuf);
 770       n = nbuf + sizeof nbuf - 1 - np;
 771     }
 772   while (n != p);
 773
 774   p = strlen (keyword) + n + 2;
 775   size = p;
 776   if (size != p)
 777     {
 778       ERROR ((0, 0,
 779         _("Generated keyword/value pair is too long (keyword=%s, length=%s)"),
 780               keyword, nbuf));
 781       obstack_free (xhdr->stk, obstack_finish (xhdr->stk));
 782       return false;
 783     }
 784   x_obstack_blank (xhdr, p);
 785   x_obstack_1grow (xhdr, '\n');
 786   cp = obstack_next_free (xhdr->stk) - xhdr->string_length - p - 1;
 787   memmove (cp + p, cp, xhdr->string_length);
 788   cp = stpcpy (cp, np);
 789   *cp++ = ' ';
 790   cp = stpcpy (cp, keyword);
 791   *cp++ = '=';
 792   return true;
 793 }
 794
 795 \f
 796 /* Implementations */
 797
 798 static void
 799 out_of_range_header (char const *keyword, char const *value,
 800                      uintmax_t minus_minval, uintmax_t maxval)
 801 {
 802   char minval_buf[UINTMAX_STRSIZE_BOUND + 1];
 803   char maxval_buf[UINTMAX_STRSIZE_BOUND];
 804   char *minval_string = umaxtostr (minus_minval, minval_buf + 1);
 805   char *maxval_string = umaxtostr (maxval, maxval_buf);
 806   if (minus_minval)
 807     *--minval_string = '-';
 808
 809   /* TRANSLATORS: The first %s is the pax extended header keyword
 810      (atime, gid, etc.).  */
 811   ERROR ((0, 0, _("Extended header %s=%s is out of range %s..%s"),
 812           keyword, value, minval_string, maxval_string));
 813 }
 814
 815 static void
 816 code_string (char const *string, char const *keyword, struct xheader *xhdr)
 817 {
 818   char *outstr;
 819   if (!utf8_convert (true, string, &outstr))
 820     {
 821       /* FIXME: report error */
 822       outstr = xstrdup (string);
 823     }
 824   xheader_print (xhdr, keyword, outstr);
 825   free (outstr);
 826 }
 827
 828 static void
 829 decode_string (char **string, char const *arg)
 830 {
 831   if (*string)
 832     {
 833       free (*string);
 834       *string = NULL;
 835     }
 836   if (!utf8_convert (false, arg, string))
 837     {
 838       /* FIXME: report error and act accordingly to --pax invalid=UTF-8 */
 839       assign_string (string, arg);
 840     }
 841 }
 842
 843 static void
 844 code_time (struct timespec t, char const *keyword, struct xheader *xhdr)
 845 {
 846   char buf[TIMESPEC_STRSIZE_BOUND];
 847   xheader_print (xhdr, keyword, code_timespec (t, buf));
 848 }
 849
 850 enum decode_time_status
 851   {
 852     decode_time_success,
 853     decode_time_range,
 854     decode_time_bad_header
 855   };
 856
 857 static enum decode_time_status
 858 _decode_time (struct timespec *ts, char const *arg, char const *keyword)
 859 {
 860   time_t s;
 861   unsigned long int ns = 0;
 862   char *p;
 863   char *arg_lim;
 864   bool negative = *arg == '-';
 865
 866   errno = 0;
 867
 868   if (ISDIGIT (arg[negative]))
 869     {
 870       if (negative)
 871         {
 872           intmax_t i = strtoimax (arg, &arg_lim, 10);
 873           if (TYPE_SIGNED (time_t) ? i < TYPE_MINIMUM (time_t) : i < 0)
 874             return decode_time_range;
 875           s = i;
 876         }
 877       else
 878         {
 879           uintmax_t i = strtoumax (arg, &arg_lim, 10);
 880           if (TYPE_MAXIMUM (time_t) < i)
 881             return decode_time_range;
 882           s = i;
 883         }
 884
 885       p = arg_lim;
 886
 887       if (errno == ERANGE)
 888         return decode_time_range;
 889
 890       if (*p == '.')
 891         {
 892           int digits = 0;
 893           bool trailing_nonzero = false;
 894
 895           while (ISDIGIT (*++p))
 896             if (digits < LOG10_BILLION)
 897               {
 898                 ns = 10 * ns + (*p - '0');
 899                 digits++;
 900               }
 901             else
 902               trailing_nonzero |= *p != '0';
 903
 904           while (digits++ < LOG10_BILLION)
 905             ns *= 10;
 906
 907           if (negative)
 908             {
 909               /* Convert "-1.10000000000001" to s == -2, ns == 89999999.
 910                  I.e., truncate time stamps towards minus infinity while
 911                  converting them to internal form.  */
 912               ns += trailing_nonzero;
 913               if (ns != 0)
 914                 {
 915                   if (s == TYPE_MINIMUM (time_t))
 916                     return decode_time_range;
 917                   s--;
 918                   ns = BILLION - ns;
 919                 }
 920             }
 921         }
 922
 923       if (! *p)
 924         {
 925           ts->tv_sec = s;
 926           ts->tv_nsec = ns;
 927           return decode_time_success;
 928         }
 929     }
 930
 931   return decode_time_bad_header;
 932 }
 933
 934 static bool
 935 decode_time (struct timespec *ts, char const *arg, char const *keyword)
 936 {
 937   switch (_decode_time (ts, arg, keyword))
 938     {
 939     case decode_time_success:
 940       return true;
 941     case decode_time_bad_header:
 942       ERROR ((0, 0, _("Malformed extended header: invalid %s=%s"),
 943               keyword, arg));
 944       return false;
 945     case decode_time_range:
 946       out_of_range_header (keyword, arg, - (uintmax_t) TYPE_MINIMUM (time_t),
 947                            TYPE_MAXIMUM (time_t));
 948       return false;
 949     }
 950   return true;
 951 }
 952
 953
 954
 955 static void
 956 code_num (uintmax_t value, char const *keyword, struct xheader *xhdr)
 957 {
 958   char sbuf[UINTMAX_STRSIZE_BOUND];
 959   xheader_print (xhdr, keyword, umaxtostr (value, sbuf));
 960 }
 961
 962 static bool
 963 decode_num (uintmax_t *num, char const *arg, uintmax_t maxval,
 964             char const *keyword)
 965 {
 966   uintmax_t u;
 967   char *arg_lim;
 968
 969   if (! (ISDIGIT (*arg)
 970          && (errno = 0, u = strtoumax (arg, &arg_lim, 10), !*arg_lim)))
 971     {
 972       ERROR ((0, 0, _("Malformed extended header: invalid %s=%s"),
 973               keyword, arg));
 974       return false;
 975     }
 976
 977   if (! (u <= maxval && errno != ERANGE))
 978     {
 979       out_of_range_header (keyword, arg, 0, maxval);
 980       return false;
 981     }
 982
 983   *num = u;
 984   return true;
 985 }
 986
 987 static void
 988 dummy_coder (struct tar_stat_info const *st __attribute__ ((unused)),
 989              char const *keyword __attribute__ ((unused)),
 990              struct xheader *xhdr __attribute__ ((unused)),
 991              void const *data __attribute__ ((unused)))
 992 {
 993 }
 994
 995 static void
 996 dummy_decoder (struct tar_stat_info *st __attribute__ ((unused)),
 997                char const *keyword __attribute__ ((unused)),
 998                char const *arg __attribute__ ((unused)),
 999                size_t size __attribute__((unused)))
1000 {
1001 }
1002
1003 static void
1004 atime_coder (struct tar_stat_info const *st, char const *keyword,
1005              struct xheader *xhdr, void const *data __attribute__ ((unused)))
1006 {
1007   code_time (st->atime, keyword, xhdr);
1008 }
1009
1010 static void
1011 atime_decoder (struct tar_stat_info *st,
1012                char const *keyword,
1013                char const *arg,
1014                size_t size __attribute__((unused)))
1015 {
1016   struct timespec ts;
1017   if (decode_time (&ts, arg, keyword))
1018     st->atime = ts;
1019 }
1020
1021 static void
1022 gid_coder (struct tar_stat_info const *st, char const *keyword,
1023            struct xheader *xhdr, void const *data __attribute__ ((unused)))
1024 {
1025   code_num (st->stat.st_gid, keyword, xhdr);
1026 }
1027
1028 static void
1029 gid_decoder (struct tar_stat_info *st,
1030              char const *keyword,
1031              char const *arg,
1032              size_t size __attribute__((unused)))
1033 {
1034   uintmax_t u;
1035   if (decode_num (&u, arg, TYPE_MAXIMUM (gid_t), keyword))
1036     st->stat.st_gid = u;
1037 }
1038
1039 static void
1040 gname_coder (struct tar_stat_info const *st, char const *keyword,
1041              struct xheader *xhdr, void const *data __attribute__ ((unused)))
1042 {
1043   code_string (st->gname, keyword, xhdr);
1044 }
1045
1046 static void
1047 gname_decoder (struct tar_stat_info *st,
1048                char const *keyword __attribute__((unused)),
1049                char const *arg,
1050                size_t size __attribute__((unused)))
1051 {
1052   decode_string (&st->gname, arg);
1053 }
1054
1055 static void
1056 linkpath_coder (struct tar_stat_info const *st, char const *keyword,
1057                 struct xheader *xhdr, void const *data __attribute__ ((unused)))
1058 {
1059   code_string (st->link_name, keyword, xhdr);
1060 }
1061
1062 static void
1063 linkpath_decoder (struct tar_stat_info *st,
1064                   char const *keyword __attribute__((unused)),
1065                   char const *arg,
1066                   size_t size __attribute__((unused)))
1067 {
1068   decode_string (&st->link_name, arg);
1069 }
1070
1071 static void
1072 ctime_coder (struct tar_stat_info const *st, char const *keyword,
1073              struct xheader *xhdr, void const *data __attribute__ ((unused)))
1074 {
1075   code_time (st->ctime, keyword, xhdr);
1076 }
1077
1078 static void
1079 ctime_decoder (struct tar_stat_info *st,
1080                char const *keyword,
1081                char const *arg,
1082                size_t size __attribute__((unused)))
1083 {
1084   struct timespec ts;
1085   if (decode_time (&ts, arg, keyword))
1086     st->ctime = ts;
1087 }
1088
1089 static void
1090 mtime_coder (struct tar_stat_info const *st, char const *keyword,
1091              struct xheader *xhdr, void const *data)
1092 {
1093   struct timespec const *mtime = data;
1094   code_time (mtime ? *mtime : st->mtime, keyword, xhdr);
1095 }
1096
1097 static void
1098 mtime_decoder (struct tar_stat_info *st,
1099                char const *keyword,
1100                char const *arg,
1101                size_t size __attribute__((unused)))
1102 {
1103   struct timespec ts;
1104   if (decode_time (&ts, arg, keyword))
1105     st->mtime = ts;
1106 }
1107
1108 static void
1109 path_coder (struct tar_stat_info const *st, char const *keyword,
1110             struct xheader *xhdr, void const *data __attribute__ ((unused)))
1111 {
1112   code_string (st->file_name, keyword, xhdr);
1113 }
1114
1115 static void
1116 path_decoder (struct tar_stat_info *st,
1117               char const *keyword __attribute__((unused)),
1118               char const *arg,
1119               size_t size __attribute__((unused)))
1120 {
1121   decode_string (&st->orig_file_name, arg);
1122   decode_string (&st->file_name, arg);
1123   st->had_trailing_slash = strip_trailing_slashes (st->file_name);
1124 }
1125
1126 static void
1127 size_coder (struct tar_stat_info const *st, char const *keyword,
1128             struct xheader *xhdr, void const *data __attribute__ ((unused)))
1129 {
1130   code_num (st->stat.st_size, keyword, xhdr);
1131 }
1132
1133 static void
1134 size_decoder (struct tar_stat_info *st,
1135               char const *keyword,
1136               char const *arg,
1137               size_t size __attribute__((unused)))
1138 {
1139   uintmax_t u;
1140   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
1141     st->stat.st_size = u;
1142 }
1143
1144 static void
1145 uid_coder (struct tar_stat_info const *st, char const *keyword,
1146            struct xheader *xhdr, void const *data __attribute__ ((unused)))
1147 {
1148   code_num (st->stat.st_uid, keyword, xhdr);
1149 }
1150
1151 static void
1152 uid_decoder (struct tar_stat_info *st,
1153              char const *keyword,
1154              char const *arg,
1155              size_t size __attribute__((unused)))
1156 {
1157   uintmax_t u;
1158   if (decode_num (&u, arg, TYPE_MAXIMUM (uid_t), keyword))
1159     st->stat.st_uid = u;
1160 }
1161
1162 static void
1163 uname_coder (struct tar_stat_info const *st, char const *keyword,
1164              struct xheader *xhdr, void const *data __attribute__ ((unused)))
1165 {
1166   code_string (st->uname, keyword, xhdr);
1167 }
1168
1169 static void
1170 uname_decoder (struct tar_stat_info *st,
1171                char const *keyword __attribute__((unused)),
1172                char const *arg,
1173                size_t size __attribute__((unused)))
1174 {
1175   decode_string (&st->uname, arg);
1176 }
1177
1178 static void
1179 sparse_size_coder (struct tar_stat_info const *st, char const *keyword,
1180              struct xheader *xhdr, void const *data)
1181 {
1182   size_coder (st, keyword, xhdr, data);
1183 }
1184
1185 static void
1186 sparse_size_decoder (struct tar_stat_info *st,
1187                      char const *keyword,
1188                      char const *arg,
1189                      size_t size __attribute__((unused)))
1190 {
1191   uintmax_t u;
1192   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
1193     st->stat.st_size = u;
1194 }
1195
1196 static void
1197 sparse_numblocks_coder (struct tar_stat_info const *st, char const *keyword,
1198                         struct xheader *xhdr,
1199                         void const *data __attribute__ ((unused)))
1200 {
1201   code_num (st->sparse_map_avail, keyword, xhdr);
1202 }
1203
1204 static void
1205 sparse_numblocks_decoder (struct tar_stat_info *st,
1206                           char const *keyword,
1207                           char const *arg,
1208                           size_t size __attribute__((unused)))
1209 {
1210   uintmax_t u;
1211   if (decode_num (&u, arg, SIZE_MAX, keyword))
1212     {
1213       st->sparse_map_size = u;
1214       st->sparse_map = xcalloc (u, sizeof st->sparse_map[0]);
1215       st->sparse_map_avail = 0;
1216     }
1217 }
1218
1219 static void
1220 sparse_offset_coder (struct tar_stat_info const *st, char const *keyword,
1221                      struct xheader *xhdr, void const *data)
1222 {
1223   size_t const *pi = data;
1224   code_num (st->sparse_map[*pi].offset, keyword, xhdr);
1225 }
1226
1227 static void
1228 sparse_offset_decoder (struct tar_stat_info *st,
1229                        char const *keyword,
1230                        char const *arg,
1231                        size_t size __attribute__((unused)))
1232 {
1233   uintmax_t u;
1234   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
1235     {
1236       if (st->sparse_map_avail < st->sparse_map_size)
1237         st->sparse_map[st->sparse_map_avail].offset = u;
1238       else
1239         ERROR ((0, 0, _("Malformed extended header: excess %s=%s"),
1240                 "GNU.sparse.offset", arg));
1241     }
1242 }
1243
1244 static void
1245 sparse_numbytes_coder (struct tar_stat_info const *st, char const *keyword,
1246                        struct xheader *xhdr, void const *data)
1247 {
1248   size_t const *pi = data;
1249   code_num (st->sparse_map[*pi].numbytes, keyword, xhdr);
1250 }
1251
1252 static void
1253 sparse_numbytes_decoder (struct tar_stat_info *st,
1254                          char const *keyword,
1255                          char const *arg,
1256                          size_t size __attribute__((unused)))
1257 {
1258   uintmax_t u;
1259   if (decode_num (&u, arg, SIZE_MAX, keyword))
1260     {
1261       if (st->sparse_map_avail < st->sparse_map_size)
1262         st->sparse_map[st->sparse_map_avail++].numbytes = u;
1263       else
1264         ERROR ((0, 0, _("Malformed extended header: excess %s=%s"),
1265                 keyword, arg));
1266     }
1267 }
1268
1269 static void
1270 sparse_map_decoder (struct tar_stat_info *st,
1271                     char const *keyword,
1272                     char const *arg,
1273                     size_t size __attribute__((unused)))
1274 {
1275   int offset = 1;
1276
1277   st->sparse_map_avail = 0;
1278   while (1)
1279     {
1280       uintmax_t u;
1281       char *delim;
1282       struct sp_array e;
1283
1284       if (!ISDIGIT (*arg))
1285         {
1286           ERROR ((0, 0, _("Malformed extended header: invalid %s=%s"),
1287                   keyword, arg));
1288           return;
1289         }
1290
1291       errno = 0;
1292       u = strtoumax (arg, &delim, 10);
1293       if (offset)
1294         {
1295           e.offset = u;
1296           if (!(u == e.offset && errno != ERANGE))
1297             {
1298               out_of_range_header (keyword, arg, 0, TYPE_MAXIMUM (off_t));
1299               return;
1300             }
1301         }
1302       else
1303         {
1304           e.numbytes = u;
1305           if (!(u == e.numbytes && errno != ERANGE))
1306             {
1307               out_of_range_header (keyword, arg, 0, TYPE_MAXIMUM (size_t));
1308               return;
1309             }
1310           if (st->sparse_map_avail < st->sparse_map_size)
1311             st->sparse_map[st->sparse_map_avail++] = e;
1312           else
1313             {
1314               ERROR ((0, 0, _("Malformed extended header: excess %s=%s"),
1315                       keyword, arg));
1316               return;
1317             }
1318         }
1319
1320       offset = !offset;
1321
1322       if (*delim == 0)
1323         break;
1324       else if (*delim != ',')
1325         {
1326           ERROR ((0, 0,
1327                   _("Malformed extended header: invalid %s: unexpected delimiter %c"),
1328                   keyword, *delim));
1329           return;
1330         }
1331
1332       arg = delim + 1;
1333     }
1334
1335   if (!offset)
1336     ERROR ((0, 0,
1337             _("Malformed extended header: invalid %s: odd number of values"),
1338             keyword));
1339 }
1340
1341 static void
1342 dumpdir_coder (struct tar_stat_info const *st, char const *keyword,
1343                struct xheader *xhdr, void const *data)
1344 {
1345   xheader_print_n (xhdr, keyword, data, dumpdir_size (data));
1346 }
1347
1348 static void
1349 dumpdir_decoder (struct tar_stat_info *st,
1350                  char const *keyword __attribute__((unused)),
1351                  char const *arg,
1352                  size_t size)
1353 {
1354   st->dumpdir = xmalloc (size);
1355   memcpy (st->dumpdir, arg, size);
1356 }
1357
1358 static void
1359 volume_label_coder (struct tar_stat_info const *st, char const *keyword,
1360                     struct xheader *xhdr, void const *data)
1361 {
1362   code_string (data, keyword, xhdr);
1363 }
1364
1365 static void
1366 volume_label_decoder (struct tar_stat_info *st,
1367                       char const *keyword __attribute__((unused)),
1368                       char const *arg,
1369                       size_t size __attribute__((unused)))
1370 {
1371   decode_string (&volume_label, arg);
1372 }
1373
1374 static void
1375 volume_size_coder (struct tar_stat_info const *st, char const *keyword,
1376                    struct xheader *xhdr, void const *data)
1377 {
1378   off_t const *v = data;
1379   code_num (*v, keyword, xhdr);
1380 }
1381
1382 static void
1383 volume_size_decoder (struct tar_stat_info *st,
1384                      char const *keyword,
1385                      char const *arg, size_t size)
1386 {
1387   uintmax_t u;
1388   if (decode_num (&u, arg, TYPE_MAXIMUM (uintmax_t), keyword))
1389     continued_file_size = u;
1390 }
1391
1392 /* FIXME: Merge with volume_size_coder */
1393 static void
1394 volume_offset_coder (struct tar_stat_info const *st, char const *keyword,
1395                      struct xheader *xhdr, void const *data)
1396 {
1397   off_t const *v = data;
1398   code_num (*v, keyword, xhdr);
1399 }
1400
1401 static void
1402 volume_offset_decoder (struct tar_stat_info *st,
1403                        char const *keyword,
1404                        char const *arg, size_t size)
1405 {
1406   uintmax_t u;
1407   if (decode_num (&u, arg, TYPE_MAXIMUM (uintmax_t), keyword))
1408     continued_file_offset = u;
1409 }
1410
1411 static void
1412 volume_filename_decoder (struct tar_stat_info *st,
1413                          char const *keyword __attribute__((unused)),
1414                          char const *arg,
1415                          size_t size __attribute__((unused)))
1416 {
1417   decode_string (&continued_file_name, arg);
1418 }
1419
1420 static void
1421 sparse_major_coder (struct tar_stat_info const *st, char const *keyword,
1422                     struct xheader *xhdr, void const *data)
1423 {
1424   code_num (st->sparse_major, keyword, xhdr);
1425 }
1426
1427 static void
1428 sparse_major_decoder (struct tar_stat_info *st,
1429                       char const *keyword,
1430                       char const *arg,
1431                       size_t size)
1432 {
1433   uintmax_t u;
1434   if (decode_num (&u, arg, TYPE_MAXIMUM (unsigned), keyword))
1435     st->sparse_major = u;
1436 }
1437
1438 static void
1439 sparse_minor_coder (struct tar_stat_info const *st, char const *keyword,
1440                       struct xheader *xhdr, void const *data)
1441 {
1442   code_num (st->sparse_minor, keyword, xhdr);
1443 }
1444
1445 static void
1446 sparse_minor_decoder (struct tar_stat_info *st,
1447                       char const *keyword,
1448                       char const *arg,
1449                       size_t size)
1450 {
1451   uintmax_t u;
1452   if (decode_num (&u, arg, TYPE_MAXIMUM (unsigned), keyword))
1453     st->sparse_minor = u;
1454 }
1455
1456 struct xhdr_tab const xhdr_tab[] = {
1457   { "atime",    atime_coder,    atime_decoder,    false },
1458   { "comment",  dummy_coder,    dummy_decoder,    false },
1459   { "charset",  dummy_coder,    dummy_decoder,    false },
1460   { "ctime",    ctime_coder,    ctime_decoder,    false },
1461   { "gid",      gid_coder,      gid_decoder,      false },
1462   { "gname",    gname_coder,    gname_decoder,    false },
1463   { "linkpath", linkpath_coder, linkpath_decoder, false },
1464   { "mtime",    mtime_coder,    mtime_decoder,    false },
1465   { "path",     path_coder,     path_decoder,     false },
1466   { "size",     size_coder,     size_decoder,     false },
1467   { "uid",      uid_coder,      uid_decoder,      false },
1468   { "uname",    uname_coder,    uname_decoder,    false },
1469
1470   /* Sparse file handling */
1471   { "GNU.sparse.name",       path_coder, path_decoder,
1472     true },
1473   { "GNU.sparse.major",      sparse_major_coder, sparse_major_decoder,
1474     true },
1475   { "GNU.sparse.minor",      sparse_minor_coder, sparse_minor_decoder,
1476     true },
1477   { "GNU.sparse.realsize",   sparse_size_coder, sparse_size_decoder,
1478     true },
1479   { "GNU.sparse.numblocks",  sparse_numblocks_coder, sparse_numblocks_decoder,
1480     true },
1481
1482   /* tar 1.14 - 1.15.90 keywords. */
1483   { "GNU.sparse.size",       sparse_size_coder, sparse_size_decoder, true },
1484   /* tar 1.14 - 1.15.1 keywords. Multiple instances of these appeared in 'x'
1485      headers, and each of them was meaningful. It confilcted with POSIX specs,
1486      which requires that "when extended header records conflict, the last one
1487      given in the header shall take precedence." */
1488   { "GNU.sparse.offset",     sparse_offset_coder, sparse_offset_decoder,
1489     true },
1490   { "GNU.sparse.numbytes",   sparse_numbytes_coder, sparse_numbytes_decoder,
1491     true },
1492   /* tar 1.15.90 keyword, introduced to remove the above-mentioned conflict. */
1493   { "GNU.sparse.map",        NULL /* Unused, see pax_dump_header() */,
1494     sparse_map_decoder, false },
1495
1496   { "GNU.dumpdir",           dumpdir_coder, dumpdir_decoder,
1497     true },
1498
1499   /* Keeps the tape/volume label. May be present only in the global headers.
1500      Equivalent to GNUTYPE_VOLHDR.  */
1501   { "GNU.volume.label", volume_label_coder, volume_label_decoder, true },
1502
1503   /* These may be present in a first global header of the archive.
1504      They provide the same functionality as GNUTYPE_MULTIVOL header.
1505      The GNU.volume.size keeps the real_s_sizeleft value, which is
1506      otherwise kept in the size field of a multivolume header.  The
1507      GNU.volume.offset keeps the offset of the start of this volume,
1508      otherwise kept in oldgnu_header.offset.  */
1509   { "GNU.volume.filename", volume_label_coder, volume_filename_decoder,
1510     true },
1511   { "GNU.volume.size", volume_size_coder, volume_size_decoder, true },
1512   { "GNU.volume.offset", volume_offset_coder, volume_offset_decoder, true },
1513
1514   { NULL, NULL, NULL, false }
1515 };