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

   1 /* POSIX extended headers for tar.
   2
   3    Copyright (C) 2003, 2004, 2005, 2006 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 2, 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 #include <stpcpy.h>
  26
  27 #include "common.h"
  28
  29 #include <fnmatch.h>
  30
  31 static bool xheader_protected_pattern_p (char const *pattern);
  32 static bool xheader_protected_keyword_p (char const *keyword);
  33 static void xheader_set_single_keyword (char *) __attribute__ ((noreturn));
  34
  35 /* Used by xheader_finish() */
  36 static void code_string (char const *string, char const *keyword,
  37                          struct xheader *xhdr);
  38 static void extended_header_init (void);
  39
  40 /* Number of global headers written so far. */
  41 static size_t global_header_count;
  42 /* FIXME: Possibly it should be reset after changing the volume.
  43    POSIX %n specification says that it is expanded to the sequence
  44    number of current global header in *the* archive. However, for
  45    multi-volume archives this will yield duplicate header names
  46    in different volumes, which I'd like to avoid. The best way
  47    to solve this would be to use per-archive header count as required
  48    by POSIX *and* set globexthdr.name to, say,
  49    $TMPDIR/GlobalHead.%p.$NUMVOLUME.%n.
  50
  51    However it should wait until buffer.c is finally rewritten */
  52
  53 \f
  54 /* Interface functions to obstacks */
  55
  56 static void
  57 x_obstack_grow (struct xheader *xhdr, const char *ptr, size_t length)
  58 {
  59   obstack_grow (xhdr->stk, ptr, length);
  60   xhdr->size += length;
  61 }
  62
  63 static void
  64 x_obstack_1grow (struct xheader *xhdr, char c)
  65 {
  66   obstack_1grow (xhdr->stk, c);
  67   xhdr->size++;
  68 }
  69
  70 static void
  71 x_obstack_blank (struct xheader *xhdr, size_t length)
  72 {
  73   obstack_blank (xhdr->stk, length);
  74   xhdr->size += length;
  75 }
  76
  77 \f
  78 /* Keyword options */
  79
  80 struct keyword_list
  81 {
  82   struct keyword_list *next;
  83   char *pattern;
  84   char *value;
  85 };
  86
  87
  88 /* List of keyword patterns set by delete= option */
  89 static struct keyword_list *keyword_pattern_list;
  90
  91 /* List of keyword/value pairs set by `keyword=value' option */
  92 static struct keyword_list *keyword_global_override_list;
  93
  94 /* List of keyword/value pairs set by `keyword:=value' option */
  95 static struct keyword_list *keyword_override_list;
  96
  97 /* List of keyword/value pairs decoded from the last 'g' type header */
  98 static struct keyword_list *global_header_override_list;
  99
 100 /* Template for the name field of an 'x' type header */
 101 static char *exthdr_name;
 102
 103 /* Template for the name field of a 'g' type header */
 104 static char *globexthdr_name;
 105
 106 bool
 107 xheader_keyword_deleted_p (const char *kw)
 108 {
 109   struct keyword_list *kp;
 110
 111   for (kp = keyword_pattern_list; kp; kp = kp->next)
 112     if (fnmatch (kp->pattern, kw, 0) == 0)
 113       return true;
 114   return false;
 115 }
 116
 117 static bool
 118 xheader_keyword_override_p (const char *keyword)
 119 {
 120   struct keyword_list *kp;
 121
 122   for (kp = keyword_override_list; kp; kp = kp->next)
 123     if (strcmp (kp->pattern, keyword) == 0)
 124       return true;
 125   return false;
 126 }
 127
 128 static void
 129 xheader_list_append (struct keyword_list **root, char const *kw,
 130                      char const *value)
 131 {
 132   struct keyword_list *kp = xmalloc (sizeof *kp);
 133   kp->pattern = xstrdup (kw);
 134   kp->value = value ? xstrdup (value) : NULL;
 135   kp->next = *root;
 136   *root = kp;
 137 }
 138
 139 static void
 140 xheader_list_destroy (struct keyword_list **root)
 141 {
 142   if (root)
 143     {
 144       struct keyword_list *kw = *root;
 145       while (kw)
 146         {
 147           struct keyword_list *next = kw->next;
 148           free (kw->pattern);
 149           free (kw->value);
 150           free (kw);
 151           kw = next;
 152         }
 153       *root = NULL;
 154     }
 155 }
 156
 157 static void
 158 xheader_set_single_keyword (char *kw)
 159 {
 160   USAGE_ERROR ((0, 0, _("Keyword %s is unknown or not yet implemented"), kw));
 161 }
 162
 163 static void
 164 xheader_set_keyword_equal (char *kw, char *eq)
 165 {
 166   bool global = true;
 167   char *p = eq;
 168
 169   if (eq[-1] == ':')
 170     {
 171       p--;
 172       global = false;
 173     }
 174
 175   while (p > kw && isspace (*p))
 176     p--;
 177
 178   *p = 0;
 179
 180   for (p = eq + 1; *p && isspace (*p); p++)
 181     ;
 182
 183   if (strcmp (kw, "delete") == 0)
 184     {
 185       if (xheader_protected_pattern_p (p))
 186         USAGE_ERROR ((0, 0, _("Pattern %s cannot be used"), quote (p)));
 187       xheader_list_append (&keyword_pattern_list, p, NULL);
 188     }
 189   else if (strcmp (kw, "exthdr.name") == 0)
 190     assign_string (&exthdr_name, p);
 191   else if (strcmp (kw, "globexthdr.name") == 0)
 192     assign_string (&globexthdr_name, p);
 193   else
 194     {
 195       if (xheader_protected_keyword_p (kw))
 196         USAGE_ERROR ((0, 0, _("Keyword %s cannot be overridden"), kw));
 197       if (global)
 198         xheader_list_append (&keyword_global_override_list, kw, p);
 199       else
 200         xheader_list_append (&keyword_override_list, kw, p);
 201     }
 202 }
 203
 204 void
 205 xheader_set_option (char *string)
 206 {
 207   char *token;
 208   for (token = strtok (string, ","); token; token = strtok (NULL, ","))
 209     {
 210       char *p = strchr (token, '=');
 211       if (!p)
 212         xheader_set_single_keyword (token);
 213       else
 214         xheader_set_keyword_equal (token, p);
 215     }
 216 }
 217
 218 /*
 219     string Includes:          Replaced By:
 220      %d                       The directory name of the file,
 221                               equivalent to the result of the
 222                               dirname utility on the translated
 223                               file name.
 224      %f                       The filename of the file, equivalent
 225                               to the result of the basename
 226                               utility on the translated file name.
 227      %p                       The process ID of the pax process.
 228      %n                       The value of the 3rd argument.
 229      %%                       A '%' character. */
 230
 231 char *
 232 xheader_format_name (struct tar_stat_info *st, const char *fmt, size_t n)
 233 {
 234   char *buf;
 235   size_t len = strlen (fmt);
 236   char *q;
 237   const char *p;
 238   char *dirp = NULL;
 239   char *dir = NULL;
 240   char *base = NULL;
 241   char pidbuf[UINTMAX_STRSIZE_BOUND];
 242   char const *pptr;
 243   char nbuf[UINTMAX_STRSIZE_BOUND];
 244   char const *nptr = NULL;
 245
 246   for (p = fmt; *p && (p = strchr (p, '%')); )
 247     {
 248       switch (p[1])
 249         {
 250         case '%':
 251           len--;
 252           break;
 253
 254         case 'd':
 255           if (st)
 256             {
 257               if (!dirp)
 258                 dirp = dir_name (st->orig_file_name);
 259               dir = safer_name_suffix (dirp, false, absolute_names_option);
 260               len += strlen (dir) - 2;
 261             }
 262           break;
 263
 264         case 'f':
 265           if (st)
 266             {
 267               base = last_component (st->orig_file_name);
 268               len += strlen (base) - 2;
 269             }
 270           break;
 271
 272         case 'p':
 273           pptr = umaxtostr (getpid (), pidbuf);
 274           len += pidbuf + sizeof pidbuf - 1 - pptr - 2;
 275           break;
 276
 277         case 'n':
 278           nptr = umaxtostr (n, nbuf);
 279           len += nbuf + sizeof nbuf - 1 - nptr - 2;
 280           break;
 281         }
 282       p++;
 283     }
 284
 285   buf = xmalloc (len + 1);
 286   for (q = buf, p = fmt; *p; )
 287     {
 288       if (*p == '%')
 289         {
 290           switch (p[1])
 291             {
 292             case '%':
 293               *q++ = *p++;
 294               p++;
 295               break;
 296
 297             case 'd':
 298               if (dir)
 299                 q = stpcpy (q, dir);
 300               p += 2;
 301               break;
 302
 303             case 'f':
 304               if (base)
 305                 q = stpcpy (q, base);
 306               p += 2;
 307               break;
 308
 309             case 'p':
 310               q = stpcpy (q, pptr);
 311               p += 2;
 312               break;
 313
 314             case 'n':
 315               if (nptr)
 316                 {
 317                   q = stpcpy (q, nptr);
 318                   p += 2;
 319                   break;
 320                 }
 321               /* else fall through */
 322
 323             default:
 324               *q++ = *p++;
 325               if (*p)
 326                 *q++ = *p++;
 327             }
 328         }
 329       else
 330         *q++ = *p++;
 331     }
 332
 333   free (dirp);
 334
 335   /* Do not allow it to end in a slash */
 336   while (q > buf && ISSLASH (q[-1]))
 337     q--;
 338   *q = 0;
 339   return buf;
 340 }
 341
 342 char *
 343 xheader_xhdr_name (struct tar_stat_info *st)
 344 {
 345   if (!exthdr_name)
 346     assign_string (&exthdr_name, "%d/PaxHeaders.%p/%f");
 347   return xheader_format_name (st, exthdr_name, 0);
 348 }
 349
 350 #define GLOBAL_HEADER_TEMPLATE "/GlobalHead.%p.%n"
 351
 352 char *
 353 xheader_ghdr_name (void)
 354 {
 355   if (!globexthdr_name)
 356     {
 357       size_t len;
 358       const char *tmp = getenv ("TMPDIR");
 359       if (!tmp)
 360         tmp = "/tmp";
 361       len = strlen (tmp) + sizeof (GLOBAL_HEADER_TEMPLATE); /* Includes nul */
 362       globexthdr_name = xmalloc (len);
 363       strcpy(globexthdr_name, tmp);
 364       strcat(globexthdr_name, GLOBAL_HEADER_TEMPLATE);
 365     }
 366
 367   return xheader_format_name (NULL, globexthdr_name, global_header_count + 1);
 368 }
 369
 370 void
 371 xheader_write (char type, char *name, struct xheader *xhdr)
 372 {
 373   union block *header;
 374   size_t size;
 375   char *p;
 376
 377   size = xhdr->size;
 378   header = start_private_header (name, size);
 379   header->header.typeflag = type;
 380
 381   simple_finish_header (header);
 382
 383   p = xhdr->buffer;
 384
 385   do
 386     {
 387       size_t len;
 388
 389       header = find_next_block ();
 390       len = BLOCKSIZE;
 391       if (len > size)
 392         len = size;
 393       memcpy (header->buffer, p, len);
 394       if (len < BLOCKSIZE)
 395         memset (header->buffer + len, 0, BLOCKSIZE - len);
 396       p += len;
 397       size -= len;
 398       set_next_block_after (header);
 399     }
 400   while (size > 0);
 401   xheader_destroy (xhdr);
 402
 403   if (type == XGLTYPE)
 404     global_header_count++;
 405 }
 406
 407 void
 408 xheader_write_global (void)
 409 {
 410   char *name;
 411   struct keyword_list *kp;
 412
 413   if (!keyword_global_override_list)
 414     return;
 415
 416   extended_header_init ();
 417   for (kp = keyword_global_override_list; kp; kp = kp->next)
 418     code_string (kp->value, kp->pattern, &extended_header);
 419   xheader_finish (&extended_header);
 420   xheader_write (XGLTYPE, name = xheader_ghdr_name (),
 421                  &extended_header);
 422   free (name);
 423 }
 424
 425 \f
 426 /* General Interface */
 427
 428 struct xhdr_tab
 429 {
 430   char const *keyword;
 431   void (*coder) (struct tar_stat_info const *, char const *,
 432                  struct xheader *, void const *data);
 433   void (*decoder) (struct tar_stat_info *, char const *, char const *, size_t);
 434   bool protect;
 435 };
 436
 437 /* This declaration must be extern, because ISO C99 section 6.9.2
 438    prohibits a tentative definition that has both internal linkage and
 439    incomplete type.  If we made it static, we'd have to declare its
 440    size which would be a maintenance pain; if we put its initializer
 441    here, we'd need a boatload of forward declarations, which would be
 442    even more of a pain.  */
 443 extern struct xhdr_tab const xhdr_tab[];
 444
 445 static struct xhdr_tab const *
 446 locate_handler (char const *keyword)
 447 {
 448   struct xhdr_tab const *p;
 449
 450   for (p = xhdr_tab; p->keyword; p++)
 451     if (strcmp (p->keyword, keyword) == 0)
 452       return p;
 453   return NULL;
 454 }
 455
 456 static bool
 457 xheader_protected_pattern_p (const char *pattern)
 458 {
 459   struct xhdr_tab const *p;
 460
 461   for (p = xhdr_tab; p->keyword; p++)
 462     if (p->protect && fnmatch (pattern, p->keyword, 0) == 0)
 463       return true;
 464   return false;
 465 }
 466
 467 static bool
 468 xheader_protected_keyword_p (const char *keyword)
 469 {
 470   struct xhdr_tab const *p;
 471
 472   for (p = xhdr_tab; p->keyword; p++)
 473     if (p->protect && strcmp (p->keyword, keyword) == 0)
 474       return true;
 475   return false;
 476 }
 477
 478 /* Decode a single extended header record, advancing *PTR to the next record.
 479    Return true on success, false otherwise.  */
 480 static bool
 481 decode_record (char **ptr,
 482                void (*handler) (void *, char const *, char const *, size_t),
 483                void *data)
 484 {
 485   char *start = *ptr;
 486   char *p = start;
 487   uintmax_t u;
 488   size_t len;
 489   char *len_lim;
 490   char const *keyword;
 491   char *nextp;
 492   size_t len_max = extended_header.buffer + extended_header.size - start;
 493
 494   while (*p == ' ' || *p == '\t')
 495     p++;
 496
 497   if (! ISDIGIT (*p))
 498     {
 499       if (*p)
 500         ERROR ((0, 0, _("Malformed extended header: missing length")));
 501       return false;
 502     }
 503
 504   errno = 0;
 505   len = u = strtoumax (p, &len_lim, 10);
 506   if (len != u || errno == ERANGE)
 507     {
 508       ERROR ((0, 0, _("Extended header length is out of allowed range")));
 509       return false;
 510     }
 511
 512   if (len_max < len)
 513     {
 514       int len_len = len_lim - p;
 515       ERROR ((0, 0, _("Extended header length %*s is out of range"),
 516               len_len, p));
 517       return false;
 518     }
 519
 520   nextp = start + len;
 521
 522   for (p = len_lim; *p == ' ' || *p == '\t'; p++)
 523     continue;
 524   if (p == len_lim)
 525     {
 526       ERROR ((0, 0,
 527               _("Malformed extended header: missing blank after length")));
 528       return false;
 529     }
 530
 531   keyword = p;
 532   p = strchr (p, '=');
 533   if (! (p && p < nextp))
 534     {
 535       ERROR ((0, 0, _("Malformed extended header: missing equal sign")));
 536       return false;
 537     }
 538
 539   if (nextp[-1] != '\n')
 540     {
 541       ERROR ((0, 0, _("Malformed extended header: missing newline")));
 542       return false;
 543     }
 544
 545   *p = nextp[-1] = '\0';
 546   handler (data, keyword, p + 1, nextp - p - 2); /* '=' + trailing '\n' */
 547   *p = '=';
 548   nextp[-1] = '\n';
 549   *ptr = nextp;
 550   return true;
 551 }
 552
 553 static void
 554 run_override_list (struct keyword_list *kp, struct tar_stat_info *st)
 555 {
 556   for (; kp; kp = kp->next)
 557     {
 558       struct xhdr_tab const *t = locate_handler (kp->pattern);
 559       if (t)
 560         t->decoder (st, t->keyword, kp->value, strlen (kp->value));
 561     }
 562 }
 563
 564 static void
 565 decx (void *data, char const *keyword, char const *value, size_t size)
 566 {
 567   struct xhdr_tab const *t;
 568   struct tar_stat_info *st = data;
 569
 570   if (xheader_keyword_deleted_p (keyword)
 571       || xheader_keyword_override_p (keyword))
 572     return;
 573
 574   t = locate_handler (keyword);
 575   if (t)
 576     t->decoder (st, keyword, value, size);
 577   else
 578     ERROR((0, 0, _("Ignoring unknown extended header keyword `%s'"),
 579            keyword));
 580 }
 581
 582 void
 583 xheader_decode (struct tar_stat_info *st)
 584 {
 585   run_override_list (keyword_global_override_list, st);
 586   run_override_list (global_header_override_list, st);
 587
 588   if (extended_header.size)
 589     {
 590       char *p = extended_header.buffer + BLOCKSIZE;
 591       while (decode_record (&p, decx, st))
 592         continue;
 593     }
 594   run_override_list (keyword_override_list, st);
 595 }
 596
 597 static void
 598 decg (void *data, char const *keyword, char const *value,
 599       size_t size __attribute__((unused)))
 600 {
 601   struct keyword_list **kwl = data;
 602   xheader_list_append (kwl, keyword, value);
 603 }
 604
 605 void
 606 xheader_decode_global (void)
 607 {
 608   if (extended_header.size)
 609     {
 610       char *p = extended_header.buffer + BLOCKSIZE;
 611
 612       xheader_list_destroy (&global_header_override_list);
 613       while (decode_record (&p, decg, &global_header_override_list))
 614         continue;
 615     }
 616 }
 617
 618 static void
 619 extended_header_init (void)
 620 {
 621   if (!extended_header.stk)
 622     {
 623       extended_header.stk = xmalloc (sizeof *extended_header.stk);
 624       obstack_init (extended_header.stk);
 625     }
 626 }
 627
 628 void
 629 xheader_store (char const *keyword, struct tar_stat_info const *st,
 630                void const *data)
 631 {
 632   struct xhdr_tab const *t;
 633
 634   if (extended_header.buffer)
 635     return;
 636   t = locate_handler (keyword);
 637   if (!t || !t->coder)
 638     return;
 639   if (xheader_keyword_deleted_p (keyword)
 640       || xheader_keyword_override_p (keyword))
 641     return;
 642   extended_header_init ();
 643   t->coder (st, keyword, &extended_header, data);
 644 }
 645
 646 void
 647 xheader_read (union block *p, size_t size)
 648 {
 649   size_t j = 0;
 650
 651   free (extended_header.buffer);
 652   size += BLOCKSIZE;
 653   extended_header.size = size;
 654   extended_header.buffer = xmalloc (size + 1);
 655   extended_header.buffer[size] = '\0';
 656
 657   do
 658     {
 659       size_t len = size;
 660
 661       if (len > BLOCKSIZE)
 662         len = BLOCKSIZE;
 663
 664       memcpy (&extended_header.buffer[j], p->buffer, len);
 665       set_next_block_after (p);
 666
 667       p = find_next_block ();
 668
 669       j += len;
 670       size -= len;
 671     }
 672   while (size > 0);
 673 }
 674
 675 static void
 676 xheader_print_n (struct xheader *xhdr, char const *keyword,
 677                  char const *value, size_t vsize)
 678 {
 679   size_t len = strlen (keyword) + vsize + 3; /* ' ' + '=' + '\n' */
 680   size_t p;
 681   size_t n = 0;
 682   char nbuf[UINTMAX_STRSIZE_BOUND];
 683   char const *np;
 684
 685   do
 686     {
 687       p = n;
 688       np = umaxtostr (len + p, nbuf);
 689       n = nbuf + sizeof nbuf - 1 - np;
 690     }
 691   while (n != p);
 692
 693   x_obstack_grow (xhdr, np, n);
 694   x_obstack_1grow (xhdr, ' ');
 695   x_obstack_grow (xhdr, keyword, strlen (keyword));
 696   x_obstack_1grow (xhdr, '=');
 697   x_obstack_grow (xhdr, value, vsize);
 698   x_obstack_1grow (xhdr, '\n');
 699 }
 700
 701 static void
 702 xheader_print (struct xheader *xhdr, char const *keyword, char const *value)
 703 {
 704   xheader_print_n (xhdr, keyword, value, strlen (value));
 705 }
 706
 707 void
 708 xheader_finish (struct xheader *xhdr)
 709 {
 710   struct keyword_list *kp;
 711
 712   for (kp = keyword_override_list; kp; kp = kp->next)
 713     code_string (kp->value, kp->pattern, xhdr);
 714
 715   xhdr->buffer = obstack_finish (xhdr->stk);
 716 }
 717
 718 void
 719 xheader_destroy (struct xheader *xhdr)
 720 {
 721   if (xhdr->stk)
 722     {
 723       obstack_free (xhdr->stk, NULL);
 724       free (xhdr->stk);
 725       xhdr->stk = NULL;
 726     }
 727   else
 728     free (xhdr->buffer);
 729   xhdr->buffer = 0;
 730   xhdr->size = 0;
 731 }
 732
 733 \f
 734 /* Buildable strings */
 735 static uintmax_t string_length;
 736
 737 void
 738 xheader_string_begin ()
 739 {
 740   string_length = 0;
 741 }
 742
 743 void
 744 xheader_string_add (char const *s)
 745 {
 746   if (extended_header.buffer)
 747     return;
 748   extended_header_init ();
 749   string_length += strlen (s);
 750   x_obstack_grow (&extended_header, s, strlen (s));
 751 }
 752
 753 bool
 754 xheader_string_end (char const *keyword)
 755 {
 756   uintmax_t len;
 757   uintmax_t p;
 758   uintmax_t n = 0;
 759   size_t size;
 760   char nbuf[UINTMAX_STRSIZE_BOUND];
 761   char const *np;
 762   char *cp;
 763
 764   if (extended_header.buffer)
 765     return false;
 766   extended_header_init ();
 767
 768   len = strlen (keyword) + string_length + 3; /* ' ' + '=' + '\n' */
 769
 770   do
 771     {
 772       p = n;
 773       np = umaxtostr (len + p, nbuf);
 774       n = nbuf + sizeof nbuf - 1 - np;
 775     }
 776   while (n != p);
 777
 778   p = strlen (keyword) + n + 2;
 779   size = p;
 780   if (size != p)
 781     {
 782       ERROR ((0, 0,
 783         _("Generated keyword/value pair is too long (keyword=%s, length=%s)"),
 784               keyword, nbuf));
 785       obstack_free (extended_header.stk, obstack_finish (extended_header.stk));
 786       return false;
 787     }
 788   x_obstack_blank (&extended_header, p);
 789   x_obstack_1grow (&extended_header, '\n');
 790   cp = obstack_next_free (extended_header.stk) - string_length - p - 1;
 791   memmove (cp + p, cp, string_length);
 792   cp = stpcpy (cp, np);
 793   *cp++ = ' ';
 794   cp = stpcpy (cp, keyword);
 795   *cp++ = '=';
 796   return true;
 797 }
 798
 799 \f
 800 /* Implementations */
 801
 802 static void
 803 out_of_range_header (char const *keyword, char const *value,
 804                      uintmax_t minus_minval, uintmax_t maxval)
 805 {
 806   char minval_buf[UINTMAX_STRSIZE_BOUND + 1];
 807   char maxval_buf[UINTMAX_STRSIZE_BOUND];
 808   char *minval_string = umaxtostr (minus_minval, minval_buf + 1);
 809   char *maxval_string = umaxtostr (maxval, maxval_buf);
 810   if (minus_minval)
 811     *--minval_string = '-';
 812
 813   /* TRANSLATORS: The first %s is the pax extended header keyword
 814      (atime, gid, etc.).  */
 815   ERROR ((0, 0, _("Extended header %s=%s is out of range %s..%s"),
 816           keyword, value, minval_string, maxval_string));
 817 }
 818
 819 static void
 820 code_string (char const *string, char const *keyword, struct xheader *xhdr)
 821 {
 822   char *outstr;
 823   if (!utf8_convert (true, string, &outstr))
 824     {
 825       /* FIXME: report error */
 826       outstr = xstrdup (string);
 827     }
 828   xheader_print (xhdr, keyword, outstr);
 829   free (outstr);
 830 }
 831
 832 static void
 833 decode_string (char **string, char const *arg)
 834 {
 835   if (*string)
 836     {
 837       free (*string);
 838       *string = NULL;
 839     }
 840   if (!utf8_convert (false, arg, string))
 841     {
 842       /* FIXME: report error and act accordingly to --pax invalid=UTF-8 */
 843       assign_string (string, arg);
 844     }
 845 }
 846
 847 static void
 848 code_time (struct timespec t, char const *keyword, struct xheader *xhdr)
 849 {
 850   char buf[TIMESPEC_STRSIZE_BOUND];
 851   xheader_print (xhdr, keyword, code_timespec (t, buf));
 852 }
 853
 854 enum decode_time_status
 855   {
 856     decode_time_success,
 857     decode_time_range,
 858     decode_time_bad_header
 859   };
 860
 861 static enum decode_time_status
 862 _decode_time (struct timespec *ts, char const *arg, char const *keyword)
 863 {
 864   time_t s;
 865   unsigned long int ns = 0;
 866   char *p;
 867   char *arg_lim;
 868   bool negative = *arg == '-';
 869
 870   errno = 0;
 871
 872   if (ISDIGIT (arg[negative]))
 873     {
 874       if (negative)
 875         {
 876           intmax_t i = strtoimax (arg, &arg_lim, 10);
 877           if (TYPE_SIGNED (time_t) ? i < TYPE_MINIMUM (time_t) : i < 0)
 878             return decode_time_range;
 879           s = i;
 880         }
 881       else
 882         {
 883           uintmax_t i = strtoumax (arg, &arg_lim, 10);
 884           if (TYPE_MAXIMUM (time_t) < i)
 885             return decode_time_range;
 886           s = i;
 887         }
 888
 889       p = arg_lim;
 890
 891       if (errno == ERANGE)
 892         return decode_time_range;
 893
 894       if (*p == '.')
 895         {
 896           int digits = 0;
 897           bool trailing_nonzero = false;
 898
 899           while (ISDIGIT (*++p))
 900             if (digits < LOG10_BILLION)
 901               {
 902                 ns = 10 * ns + (*p - '0');
 903                 digits++;
 904               }
 905             else
 906               trailing_nonzero |= *p != '0';
 907
 908           while (digits++ < LOG10_BILLION)
 909             ns *= 10;
 910
 911           if (negative)
 912             {
 913               /* Convert "-1.10000000000001" to s == -2, ns == 89999999.
 914                  I.e., truncate time stamps towards minus infinity while
 915                  converting them to internal form.  */
 916               ns += trailing_nonzero;
 917               if (ns != 0)
 918                 {
 919                   if (s == TYPE_MINIMUM (time_t))
 920                     return decode_time_range;
 921                   s--;
 922                   ns = BILLION - ns;
 923                 }
 924             }
 925         }
 926
 927       if (! *p)
 928         {
 929           ts->tv_sec = s;
 930           ts->tv_nsec = ns;
 931           return decode_time_success;
 932         }
 933     }
 934
 935   return decode_time_bad_header;
 936 }
 937
 938 static bool
 939 decode_time (struct timespec *ts, char const *arg, char const *keyword)
 940 {
 941   switch (_decode_time (ts, arg, keyword))
 942     {
 943     case decode_time_success:
 944       return true;
 945     case decode_time_bad_header:
 946       ERROR ((0, 0, _("Malformed extended header: invalid %s=%s"),
 947               keyword, arg));
 948       return false;
 949     case decode_time_range:
 950       out_of_range_header (keyword, arg, - (uintmax_t) TYPE_MINIMUM (time_t),
 951                            TYPE_MAXIMUM (time_t));
 952       return false;
 953     }
 954   return true;
 955 }
 956
 957
 958
 959 static void
 960 code_num (uintmax_t value, char const *keyword, struct xheader *xhdr)
 961 {
 962   char sbuf[UINTMAX_STRSIZE_BOUND];
 963   xheader_print (xhdr, keyword, umaxtostr (value, sbuf));
 964 }
 965
 966 static bool
 967 decode_num (uintmax_t *num, char const *arg, uintmax_t maxval,
 968             char const *keyword)
 969 {
 970   uintmax_t u;
 971   char *arg_lim;
 972
 973   if (! (ISDIGIT (*arg)
 974          && (errno = 0, u = strtoumax (arg, &arg_lim, 10), !*arg_lim)))
 975     {
 976       ERROR ((0, 0, _("Malformed extended header: invalid %s=%s"),
 977               keyword, arg));
 978       return false;
 979     }
 980
 981   if (! (u <= maxval && errno != ERANGE))
 982     {
 983       out_of_range_header (keyword, arg, 0, maxval);
 984       return false;
 985     }
 986
 987   *num = u;
 988   return true;
 989 }
 990
 991 static void
 992 dummy_coder (struct tar_stat_info const *st __attribute__ ((unused)),
 993              char const *keyword __attribute__ ((unused)),
 994              struct xheader *xhdr __attribute__ ((unused)),
 995              void const *data __attribute__ ((unused)))
 996 {
 997 }
 998
 999 static void
1000 dummy_decoder (struct tar_stat_info *st __attribute__ ((unused)),
1001                char const *keyword __attribute__ ((unused)),
1002                char const *arg __attribute__ ((unused)),
1003                size_t size __attribute__((unused)))
1004 {
1005 }
1006
1007 static void
1008 atime_coder (struct tar_stat_info const *st, char const *keyword,
1009              struct xheader *xhdr, void const *data __attribute__ ((unused)))
1010 {
1011   code_time (st->atime, keyword, xhdr);
1012 }
1013
1014 static void
1015 atime_decoder (struct tar_stat_info *st,
1016                char const *keyword,
1017                char const *arg,
1018                size_t size __attribute__((unused)))
1019 {
1020   struct timespec ts;
1021   if (decode_time (&ts, arg, keyword))
1022     st->atime = ts;
1023 }
1024
1025 static void
1026 gid_coder (struct tar_stat_info const *st, char const *keyword,
1027            struct xheader *xhdr, void const *data __attribute__ ((unused)))
1028 {
1029   code_num (st->stat.st_gid, keyword, xhdr);
1030 }
1031
1032 static void
1033 gid_decoder (struct tar_stat_info *st,
1034              char const *keyword,
1035              char const *arg,
1036              size_t size __attribute__((unused)))
1037 {
1038   uintmax_t u;
1039   if (decode_num (&u, arg, TYPE_MAXIMUM (gid_t), keyword))
1040     st->stat.st_gid = u;
1041 }
1042
1043 static void
1044 gname_coder (struct tar_stat_info const *st, char const *keyword,
1045              struct xheader *xhdr, void const *data __attribute__ ((unused)))
1046 {
1047   code_string (st->gname, keyword, xhdr);
1048 }
1049
1050 static void
1051 gname_decoder (struct tar_stat_info *st,
1052                char const *keyword __attribute__((unused)),
1053                char const *arg,
1054                size_t size __attribute__((unused)))
1055 {
1056   decode_string (&st->gname, arg);
1057 }
1058
1059 static void
1060 linkpath_coder (struct tar_stat_info const *st, char const *keyword,
1061                 struct xheader *xhdr, void const *data __attribute__ ((unused)))
1062 {
1063   code_string (st->link_name, keyword, xhdr);
1064 }
1065
1066 static void
1067 linkpath_decoder (struct tar_stat_info *st,
1068                   char const *keyword __attribute__((unused)),
1069                   char const *arg,
1070                   size_t size __attribute__((unused)))
1071 {
1072   decode_string (&st->link_name, arg);
1073 }
1074
1075 static void
1076 ctime_coder (struct tar_stat_info const *st, char const *keyword,
1077              struct xheader *xhdr, void const *data __attribute__ ((unused)))
1078 {
1079   code_time (st->ctime, keyword, xhdr);
1080 }
1081
1082 static void
1083 ctime_decoder (struct tar_stat_info *st,
1084                char const *keyword,
1085                char const *arg,
1086                size_t size __attribute__((unused)))
1087 {
1088   struct timespec ts;
1089   if (decode_time (&ts, arg, keyword))
1090     st->ctime = ts;
1091 }
1092
1093 static void
1094 mtime_coder (struct tar_stat_info const *st, char const *keyword,
1095              struct xheader *xhdr, void const *data)
1096 {
1097   struct timespec const *mtime = data;
1098   code_time (mtime ? *mtime : st->mtime, keyword, xhdr);
1099 }
1100
1101 static void
1102 mtime_decoder (struct tar_stat_info *st,
1103                char const *keyword,
1104                char const *arg,
1105                size_t size __attribute__((unused)))
1106 {
1107   struct timespec ts;
1108   if (decode_time (&ts, arg, keyword))
1109     st->mtime = ts;
1110 }
1111
1112 static void
1113 path_coder (struct tar_stat_info const *st, char const *keyword,
1114             struct xheader *xhdr, void const *data __attribute__ ((unused)))
1115 {
1116   code_string (st->file_name, keyword, xhdr);
1117 }
1118
1119 static void
1120 path_decoder (struct tar_stat_info *st,
1121               char const *keyword __attribute__((unused)),
1122               char const *arg,
1123               size_t size __attribute__((unused)))
1124 {
1125   decode_string (&st->orig_file_name, arg);
1126   decode_string (&st->file_name, arg);
1127   st->had_trailing_slash = strip_trailing_slashes (st->file_name);
1128 }
1129
1130 static void
1131 size_coder (struct tar_stat_info const *st, char const *keyword,
1132             struct xheader *xhdr, void const *data __attribute__ ((unused)))
1133 {
1134   code_num (st->stat.st_size, keyword, xhdr);
1135 }
1136
1137 static void
1138 size_decoder (struct tar_stat_info *st,
1139               char const *keyword,
1140               char const *arg,
1141               size_t size __attribute__((unused)))
1142 {
1143   uintmax_t u;
1144   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
1145     st->stat.st_size = u;
1146 }
1147
1148 static void
1149 uid_coder (struct tar_stat_info const *st, char const *keyword,
1150            struct xheader *xhdr, void const *data __attribute__ ((unused)))
1151 {
1152   code_num (st->stat.st_uid, keyword, xhdr);
1153 }
1154
1155 static void
1156 uid_decoder (struct tar_stat_info *st,
1157              char const *keyword,
1158              char const *arg,
1159              size_t size __attribute__((unused)))
1160 {
1161   uintmax_t u;
1162   if (decode_num (&u, arg, TYPE_MAXIMUM (uid_t), keyword))
1163     st->stat.st_uid = u;
1164 }
1165
1166 static void
1167 uname_coder (struct tar_stat_info const *st, char const *keyword,
1168              struct xheader *xhdr, void const *data __attribute__ ((unused)))
1169 {
1170   code_string (st->uname, keyword, xhdr);
1171 }
1172
1173 static void
1174 uname_decoder (struct tar_stat_info *st,
1175                char const *keyword __attribute__((unused)),
1176                char const *arg,
1177                size_t size __attribute__((unused)))
1178 {
1179   decode_string (&st->uname, arg);
1180 }
1181
1182 static void
1183 sparse_size_coder (struct tar_stat_info const *st, char const *keyword,
1184              struct xheader *xhdr, void const *data)
1185 {
1186   size_coder (st, keyword, xhdr, data);
1187 }
1188
1189 static void
1190 sparse_size_decoder (struct tar_stat_info *st,
1191                      char const *keyword,
1192                      char const *arg,
1193                      size_t size __attribute__((unused)))
1194 {
1195   uintmax_t u;
1196   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
1197     st->stat.st_size = u;
1198 }
1199
1200 static void
1201 sparse_numblocks_coder (struct tar_stat_info const *st, char const *keyword,
1202                         struct xheader *xhdr,
1203                         void const *data __attribute__ ((unused)))
1204 {
1205   code_num (st->sparse_map_avail, keyword, xhdr);
1206 }
1207
1208 static void
1209 sparse_numblocks_decoder (struct tar_stat_info *st,
1210                           char const *keyword,
1211                           char const *arg,
1212                           size_t size __attribute__((unused)))
1213 {
1214   uintmax_t u;
1215   if (decode_num (&u, arg, SIZE_MAX, keyword))
1216     {
1217       st->sparse_map_size = u;
1218       st->sparse_map = xcalloc (u, sizeof st->sparse_map[0]);
1219       st->sparse_map_avail = 0;
1220     }
1221 }
1222
1223 static void
1224 sparse_offset_coder (struct tar_stat_info const *st, char const *keyword,
1225                      struct xheader *xhdr, void const *data)
1226 {
1227   size_t const *pi = data;
1228   code_num (st->sparse_map[*pi].offset, keyword, xhdr);
1229 }
1230
1231 static void
1232 sparse_offset_decoder (struct tar_stat_info *st,
1233                        char const *keyword,
1234                        char const *arg,
1235                        size_t size __attribute__((unused)))
1236 {
1237   uintmax_t u;
1238   if (decode_num (&u, arg, TYPE_MAXIMUM (off_t), keyword))
1239     {
1240       if (st->sparse_map_avail < st->sparse_map_size)
1241         st->sparse_map[st->sparse_map_avail].offset = u;
1242       else
1243         ERROR ((0, 0, _("Malformed extended header: excess %s=%s"),
1244                 "GNU.sparse.offset", arg));
1245     }
1246 }
1247
1248 static void
1249 sparse_numbytes_coder (struct tar_stat_info const *st, char const *keyword,
1250                        struct xheader *xhdr, void const *data)
1251 {
1252   size_t const *pi = data;
1253   code_num (st->sparse_map[*pi].numbytes, keyword, xhdr);
1254 }
1255
1256 static void
1257 sparse_numbytes_decoder (struct tar_stat_info *st,
1258                          char const *keyword,
1259                          char const *arg,
1260                          size_t size __attribute__((unused)))
1261 {
1262   uintmax_t u;
1263   if (decode_num (&u, arg, SIZE_MAX, keyword))
1264     {
1265       if (st->sparse_map_avail < st->sparse_map_size)
1266         st->sparse_map[st->sparse_map_avail++].numbytes = u;
1267       else
1268         ERROR ((0, 0, _("Malformed extended header: excess %s=%s"),
1269                 keyword, arg));
1270     }
1271 }
1272
1273 static void
1274 sparse_map_decoder (struct tar_stat_info *st,
1275                     char const *keyword,
1276                     char const *arg,
1277                     size_t size __attribute__((unused)))
1278 {
1279   int offset = 1;
1280
1281   st->sparse_map_avail = 0;
1282   while (1)
1283     {
1284       uintmax_t u;
1285       char *delim;
1286       struct sp_array e;
1287
1288       if (!ISDIGIT (*arg))
1289         {
1290           ERROR ((0, 0, _("Malformed extended header: invalid %s=%s"),
1291                   keyword, arg));
1292           return;
1293         }
1294
1295       errno = 0;
1296       u = strtoumax (arg, &delim, 10);
1297       if (offset)
1298         {
1299           e.offset = u;
1300           if (!(u == e.offset && errno != ERANGE))
1301             {
1302               out_of_range_header (keyword, arg, 0, TYPE_MAXIMUM (off_t));
1303               return;
1304             }
1305         }
1306       else
1307         {
1308           e.numbytes = u;
1309           if (!(u == e.numbytes && errno != ERANGE))
1310             {
1311               out_of_range_header (keyword, arg, 0, TYPE_MAXIMUM (size_t));
1312               return;
1313             }
1314           if (st->sparse_map_avail < st->sparse_map_size)
1315             st->sparse_map[st->sparse_map_avail++] = e;
1316           else
1317             {
1318               ERROR ((0, 0, _("Malformed extended header: excess %s=%s"),
1319                       keyword, arg));
1320               return;
1321             }
1322         }
1323
1324       offset = !offset;
1325
1326       if (*delim == 0)
1327         break;
1328       else if (*delim != ',')
1329         {
1330           ERROR ((0, 0,
1331                   _("Malformed extended header: invalid %s: unexpected delimiter %c"),
1332                   keyword, *delim));
1333           return;
1334         }
1335
1336       arg = delim + 1;
1337     }
1338
1339   if (!offset)
1340     ERROR ((0, 0,
1341             _("Malformed extended header: invalid %s: odd number of values"),
1342             keyword));
1343 }
1344
1345 static void
1346 dumpdir_coder (struct tar_stat_info const *st, char const *keyword,
1347                struct xheader *xhdr, void const *data)
1348 {
1349   xheader_print_n (xhdr, keyword, data, dumpdir_size (data));
1350 }
1351
1352 static void
1353 dumpdir_decoder (struct tar_stat_info *st,
1354                  char const *keyword __attribute__((unused)),
1355                  char const *arg,
1356                  size_t size)
1357 {
1358   st->dumpdir = xmalloc (size);
1359   memcpy (st->dumpdir, arg, size);
1360 }
1361
1362 static void
1363 volume_label_coder (struct tar_stat_info const *st, char const *keyword,
1364                     struct xheader *xhdr, void const *data)
1365 {
1366   code_string (data, keyword, xhdr);
1367 }
1368
1369 static void
1370 volume_label_decoder (struct tar_stat_info *st,
1371                       char const *keyword __attribute__((unused)),
1372                       char const *arg,
1373                       size_t size __attribute__((unused)))
1374 {
1375   decode_string (&volume_label, arg);
1376 }
1377
1378 static void
1379 volume_size_coder (struct tar_stat_info const *st, char const *keyword,
1380                    struct xheader *xhdr, void const *data)
1381 {
1382   off_t const *v = data;
1383   code_num (*v, keyword, xhdr);
1384 }
1385
1386 static void
1387 volume_size_decoder (struct tar_stat_info *st,
1388                      char const *keyword,
1389                      char const *arg, size_t size)
1390 {
1391   uintmax_t u;
1392   if (decode_num (&u, arg, TYPE_MAXIMUM (uintmax_t), keyword))
1393     continued_file_size = u;
1394 }
1395
1396 /* FIXME: Merge with volume_size_coder */
1397 static void
1398 volume_offset_coder (struct tar_stat_info const *st, char const *keyword,
1399                      struct xheader *xhdr, void const *data)
1400 {
1401   off_t const *v = data;
1402   code_num (*v, keyword, xhdr);
1403 }
1404
1405 static void
1406 volume_offset_decoder (struct tar_stat_info *st,
1407                        char const *keyword,
1408                        char const *arg, size_t size)
1409 {
1410   uintmax_t u;
1411   if (decode_num (&u, arg, TYPE_MAXIMUM (uintmax_t), keyword))
1412     continued_file_offset = u;
1413 }
1414
1415 static void
1416 volume_filename_decoder (struct tar_stat_info *st,
1417                          char const *keyword __attribute__((unused)),
1418                          char const *arg,
1419                          size_t size __attribute__((unused)))
1420 {
1421   decode_string (&continued_file_name, arg);
1422 }
1423
1424 static void
1425 sparse_major_coder (struct tar_stat_info const *st, char const *keyword,
1426                     struct xheader *xhdr, void const *data)
1427 {
1428   code_num (st->sparse_major, keyword, xhdr);
1429 }
1430
1431 static void
1432 sparse_major_decoder (struct tar_stat_info *st,
1433                       char const *keyword,
1434                       char const *arg,
1435                       size_t size)
1436 {
1437   uintmax_t u;
1438   if (decode_num (&u, arg, TYPE_MAXIMUM (unsigned), keyword))
1439     st->sparse_major = u;
1440 }
1441
1442 static void
1443 sparse_minor_coder (struct tar_stat_info const *st, char const *keyword,
1444                       struct xheader *xhdr, void const *data)
1445 {
1446   code_num (st->sparse_minor, keyword, xhdr);
1447 }
1448
1449 static void
1450 sparse_minor_decoder (struct tar_stat_info *st,
1451                       char const *keyword,
1452                       char const *arg,
1453                       size_t size)
1454 {
1455   uintmax_t u;
1456   if (decode_num (&u, arg, TYPE_MAXIMUM (unsigned), keyword))
1457     st->sparse_minor = u;
1458 }
1459
1460 struct xhdr_tab const xhdr_tab[] = {
1461   { "atime",    atime_coder,    atime_decoder,    false },
1462   { "comment",  dummy_coder,    dummy_decoder,    false },
1463   { "charset",  dummy_coder,    dummy_decoder,    false },
1464   { "ctime",    ctime_coder,    ctime_decoder,    false },
1465   { "gid",      gid_coder,      gid_decoder,      false },
1466   { "gname",    gname_coder,    gname_decoder,    false },
1467   { "linkpath", linkpath_coder, linkpath_decoder, false },
1468   { "mtime",    mtime_coder,    mtime_decoder,    false },
1469   { "path",     path_coder,     path_decoder,     false },
1470   { "size",     size_coder,     size_decoder,     false },
1471   { "uid",      uid_coder,      uid_decoder,      false },
1472   { "uname",    uname_coder,    uname_decoder,    false },
1473
1474   /* Sparse file handling */
1475   { "GNU.sparse.name",       path_coder, path_decoder,
1476     true },
1477   { "GNU.sparse.major",      sparse_major_coder, sparse_major_decoder,
1478     true },
1479   { "GNU.sparse.minor",      sparse_minor_coder, sparse_minor_decoder,
1480     true },
1481   { "GNU.sparse.realsize",   sparse_size_coder, sparse_size_decoder,
1482     true },
1483   { "GNU.sparse.numblocks",  sparse_numblocks_coder, sparse_numblocks_decoder,
1484     true },
1485
1486   /* tar 1.14 - 1.15.90 keywords. */
1487   { "GNU.sparse.size",       sparse_size_coder, sparse_size_decoder, true },
1488   /* tar 1.14 - 1.15.1 keywords. Multiple instances of these appeared in 'x'
1489      headers, and each of them was meaningful. It confilcted with POSIX specs,
1490      which requires that "when extended header records conflict, the last one
1491      given in the header shall take precedence." */
1492   { "GNU.sparse.offset",     sparse_offset_coder, sparse_offset_decoder,
1493     true },
1494   { "GNU.sparse.numbytes",   sparse_numbytes_coder, sparse_numbytes_decoder,
1495     true },
1496   /* tar 1.15.90 keyword, introduced to remove the above-mentioned conflict. */
1497   { "GNU.sparse.map",        NULL /* Unused, see pax_dump_header() */,
1498     sparse_map_decoder, false },
1499
1500   { "GNU.dumpdir",           dumpdir_coder, dumpdir_decoder,
1501     true },
1502
1503   /* Keeps the tape/volume label. May be present only in the global headers.
1504      Equivalent to GNUTYPE_VOLHDR.  */
1505   { "GNU.volume.label", volume_label_coder, volume_label_decoder, true },
1506
1507   /* These may be present in a first global header of the archive.
1508      They provide the same functionality as GNUTYPE_MULTIVOL header.
1509      The GNU.volume.size keeps the real_s_sizeleft value, which is
1510      otherwise kept in the size field of a multivolume header.  The
1511      GNU.volume.offset keeps the offset of the start of this volume,
1512      otherwise kept in oldgnu_header.offset.  */
1513   { "GNU.volume.filename", volume_label_coder, volume_filename_decoder,
1514     true },
1515   { "GNU.volume.size", volume_size_coder, volume_size_decoder, true },
1516   { "GNU.volume.offset", volume_offset_coder, volume_offset_decoder, true },
1517
1518   { NULL, NULL, NULL, false }
1519 };