src/vfs/cpio/cpio.c

src/vfs/cpio/cpio.c
/* */
This source file includes following definitions.
cpio_defer_find
cpio_skip_padding
cpio_new_archive
cpio_free_archive
cpio_open_cpio_file
cpio_read_head
cpio_find_head
cpio_create_entry
cpio_read_bin_head
cpio_read_oldc_head
cpio_read_crc_head
cpio_open_archive
cpio_super_check
cpio_super_same
cpio_read
cpio_fh_open
vfs_init_cpiofs
   1 /*
   2    Virtual File System: GNU Tar file system.
   3 
   4    Copyright (C) 2000-2025
   5    Free Software Foundation, Inc.
   6 
   7    Written by:
   8    Jan Hudec, 2000
   9    Slava Zanko <slavazanko@gmail.com>, 2013
  10 
  11    This file is part of the Midnight Commander.
  12 
  13    The Midnight Commander is free software: you can redistribute it
  14    and/or modify it under the terms of the GNU General Public License as
  15    published by the Free Software Foundation, either version 3 of the License,
  16    or (at your option) any later version.
  17 
  18    The Midnight Commander is distributed in the hope that it will be useful,
  19    but WITHOUT ANY WARRANTY; without even the implied warranty of
  20    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21    GNU General Public License for more details.
  22 
  23    You should have received a copy of the GNU General Public License
  24    along with this program.  If not, see <https://www.gnu.org/licenses/>.
  25  */
  26 
  27 /** \file
  28  *  \brief Source: Virtual File System: GNU Tar file system.
  29  *  \author Jan Hudec
  30  *  \date 2000
  31  */
  32 
  33 #include <config.h>
  34 
  35 #include <errno.h>
  36 #include <sys/types.h>
  37 #include <sys/stat.h>
  38 
  39 #include "lib/global.h"
  40 #include "lib/unixcompat.h"
  41 #include "lib/util.h"
  42 #include "lib/widget.h"  // message()
  43 
  44 #include "lib/vfs/vfs.h"
  45 #include "lib/vfs/utilvfs.h"
  46 #include "lib/vfs/xdirentry.h"
  47 #include "lib/vfs/gc.h"  // vfs_rmstamp
  48 
  49 #include "cpio.h"
  50 
  51 /*** global variables ****************************************************************************/
  52 
  53 /*** file scope macro definitions ****************************************************************/
  54 
  55 #define CPIO_SUPER(super) ((cpio_super_t *) (super))
  56 
  57 #define CPIO_POS(super)   cpio_position
  58 /* If some time reentrancy should be needed change it to */
  59 /* #define CPIO_POS(super) (super)->u.arch.fd */
  60 
  61 #define CPIO_SEEK_SET(super, where)                                                                \
  62     mc_lseek (CPIO_SUPER (super)->fd, CPIO_POS (super) = (where), SEEK_SET)
  63 #define CPIO_SEEK_CUR(super, where)                                                                \
  64     mc_lseek (CPIO_SUPER (super)->fd, CPIO_POS (super) += (where), SEEK_SET)
  65 
  66 #define MAGIC_LENGTH (6)  // How many bytes we have to read ahead
  67 #define SEEKBACK     CPIO_SEEK_CUR (super, ptr - top)
  68 #define RETURN(x)    return (CPIO_SUPER (super)->type = (x))
  69 #define TYPEIS(x)    ((CPIO_SUPER (super)->type == CPIO_UNKNOWN) || (CPIO_SUPER (super)->type == (x)))
  70 
  71 #define HEAD_LENGTH  (26)
  72 
  73 /*** file scope type declarations ****************************************************************/
  74 
  75 enum
  76 {
  77     STATUS_START,
  78     STATUS_OK,
  79     STATUS_TRAIL,
  80     STATUS_FAIL,
  81     STATUS_EOF
  82 };
  83 
  84 enum
  85 {
  86     CPIO_UNKNOWN = 0,  // Not determined yet
  87     CPIO_BIN,          // Binary format
  88     CPIO_BINRE,        // Binary format, reverse endianness
  89     CPIO_OLDC,         // Old ASCII format
  90     CPIO_NEWC,         // New ASCII format
  91     CPIO_CRC           // New ASCII format + CRC
  92 };
  93 
  94 struct old_cpio_header
  95 {
  96     unsigned short c_magic;
  97     short c_dev;
  98     unsigned short c_ino;
  99     unsigned short c_mode;
 100     unsigned short c_uid;
 101     unsigned short c_gid;
 102     unsigned short c_nlink;
 103     short c_rdev;
 104     unsigned short c_mtimes[2];
 105     unsigned short c_namesize;
 106     unsigned short c_filesizes[2];
 107 };
 108 
 109 struct new_cpio_header
 110 {
 111     unsigned short c_magic;
 112     unsigned long c_ino;
 113     unsigned long c_mode;
 114     unsigned long c_uid;
 115     unsigned long c_gid;
 116     unsigned long c_nlink;
 117     unsigned long c_mtime;
 118     unsigned long c_filesize;
 119     long c_dev;
 120     long c_devmin;
 121     long c_rdev;
 122     long c_rdevmin;
 123     unsigned long c_namesize;
 124     unsigned long c_chksum;
 125 };
 126 
 127 typedef struct
 128 {
 129     unsigned long inumber;
 130     dev_t device;
 131     struct vfs_s_inode *inode;
 132 } defer_inode;
 133 
 134 typedef struct
 135 {
 136     struct vfs_s_super base;  // base class
 137 
 138     int fd;
 139     struct stat st;
 140     int type;          // Type of the archive
 141     GSList *deferred;  // List of inodes for which another entries may appear
 142 } cpio_super_t;
 143 
 144 /*** forward declarations (file scope functions) *************************************************/
 145 
 146 static ssize_t cpio_find_head (struct vfs_class *me, struct vfs_s_super *super);
 147 static ssize_t cpio_read_bin_head (struct vfs_class *me, struct vfs_s_super *super);
 148 static ssize_t cpio_read_oldc_head (struct vfs_class *me, struct vfs_s_super *super);
 149 static ssize_t cpio_read_crc_head (struct vfs_class *me, struct vfs_s_super *super);
 150 
 151 /*** file scope variables ************************************************************************/
 152 
 153 static struct vfs_s_subclass cpio_subclass;
 154 static struct vfs_class *vfs_cpiofs_ops = VFS_CLASS (&cpio_subclass);
 155 
 156 static off_t cpio_position;
 157 
 158 /* --------------------------------------------------------------------------------------------- */
 159 /*** file scope functions ************************************************************************/
 160 /* --------------------------------------------------------------------------------------------- */
 161 
 162 static int
 163 cpio_defer_find (const void *a, const void *b)
     /*   */
 164 {
 165     const defer_inode *a1 = (const defer_inode *) a;
 166     const defer_inode *b1 = (const defer_inode *) b;
 167 
 168     return (a1->inumber == b1->inumber && a1->device == b1->device) ? 0 : 1;
 169 }
 170 
 171 /* --------------------------------------------------------------------------------------------- */
 172 
 173 static ssize_t
 174 cpio_skip_padding (struct vfs_s_super *super)
     /*   */
 175 {
 176     switch (CPIO_SUPER (super)->type)
 177     {
 178     case CPIO_BIN:
 179     case CPIO_BINRE:
 180         return CPIO_SEEK_CUR (super, (2 - (CPIO_POS (super) % 2)) % 2);
 181     case CPIO_NEWC:
 182     case CPIO_CRC:
 183         return CPIO_SEEK_CUR (super, (4 - (CPIO_POS (super) % 4)) % 4);
 184     case CPIO_OLDC:
 185         return CPIO_POS (super);
 186     default:
 187         g_assert_not_reached ();
 188         return 42;  // & the compiler is happy :-)
 189     }
 190 }
 191 
 192 /* --------------------------------------------------------------------------------------------- */
 193 
 194 static struct vfs_s_super *
 195 cpio_new_archive (struct vfs_class *me)
     /*   */
 196 {
 197     cpio_super_t *arch;
 198 
 199     arch = g_new0 (cpio_super_t, 1);
 200     arch->base.me = me;
 201     arch->fd = -1;  // for now
 202     arch->type = CPIO_UNKNOWN;
 203 
 204     return VFS_SUPER (arch);
 205 }
 206 
 207 /* --------------------------------------------------------------------------------------------- */
 208 
 209 static void
 210 cpio_free_archive (struct vfs_class *me, struct vfs_s_super *super)
     /*   */
 211 {
 212     cpio_super_t *arch = CPIO_SUPER (super);
 213 
 214     (void) me;
 215 
 216     if (arch->fd != -1)
 217     {
 218         mc_close (arch->fd);
 219         arch->fd = -1;
 220     }
 221 
 222     g_clear_slist (&arch->deferred, g_free);
 223 }
 224 
 225 /* --------------------------------------------------------------------------------------------- */
 226 
 227 static int
 228 cpio_open_cpio_file (struct vfs_class *me, struct vfs_s_super *super, const vfs_path_t *vpath)
     /*   */
 229 {
 230     int fd, type;
 231     cpio_super_t *arch;
 232     mode_t mode;
 233     struct vfs_s_inode *root;
 234 
 235     fd = mc_open (vpath, O_RDONLY);
 236     if (fd == -1)
 237     {
 238         message (D_ERROR, MSG_ERROR, _ ("Cannot open cpio archive\n%s"), vfs_path_as_str (vpath));
 239         return -1;
 240     }
 241 
 242     super->name = g_strdup (vfs_path_as_str (vpath));
 243     arch = CPIO_SUPER (super);
 244     mc_stat (vpath, &arch->st);
 245 
 246     type = get_compression_type (fd, super->name);
 247     if (type == COMPRESSION_NONE)
 248         mc_lseek (fd, 0, SEEK_SET);
 249     else
 250     {
 251         char *s;
 252         vfs_path_t *tmp_vpath;
 253 
 254         mc_close (fd);
 255         s = g_strconcat (super->name, decompress_extension (type), (char *) NULL);
 256         tmp_vpath = vfs_path_from_str_flags (s, VPF_NO_CANON);
 257         fd = mc_open (tmp_vpath, O_RDONLY);
 258         vfs_path_free (tmp_vpath, TRUE);
 259         if (fd == -1)
 260         {
 261             message (D_ERROR, MSG_ERROR, _ ("Cannot open cpio archive\n%s"), s);
 262             g_free (s);
 263             MC_PTR_FREE (super->name);
 264             return -1;
 265         }
 266         g_free (s);
 267     }
 268 
 269     arch->fd = fd;
 270     mode = arch->st.st_mode & 07777;
 271     mode |= (mode & 0444) >> 2;  // set eXec where Read is
 272     mode |= S_IFDIR;
 273 
 274     root = vfs_s_new_inode (me, super, &arch->st);
 275     root->st.st_mode = mode;
 276     root->data_offset = -1;
 277     root->st.st_nlink++;
 278     root->st.st_dev = VFS_SUBCLASS (me)->rdev++;
 279 
 280     super->root = root;
 281 
 282     CPIO_SEEK_SET (super, 0);
 283 
 284     return fd;
 285 }
 286 
 287 /* --------------------------------------------------------------------------------------------- */
 288 
 289 static ssize_t
 290 cpio_read_head (struct vfs_class *me, struct vfs_s_super *super)
     /*   */
 291 {
 292     switch (cpio_find_head (me, super))
 293     {
 294     case CPIO_UNKNOWN:
 295         return -1;
 296     case CPIO_BIN:
 297     case CPIO_BINRE:
 298         return cpio_read_bin_head (me, super);
 299     case CPIO_OLDC:
 300         return cpio_read_oldc_head (me, super);
 301     case CPIO_NEWC:
 302     case CPIO_CRC:
 303         return cpio_read_crc_head (me, super);
 304     default:
 305         g_assert_not_reached ();
 306         return 42;  // & the compiler is happy :-)
 307     }
 308 }
 309 
 310 /* --------------------------------------------------------------------------------------------- */
 311 
 312 static ssize_t
 313 cpio_find_head (struct vfs_class *me, struct vfs_s_super *super)
     /*   */
 314 {
 315     cpio_super_t *arch = CPIO_SUPER (super);
 316     char buf[BUF_SMALL * 2];
 317     ssize_t ptr = 0;
 318     ssize_t top;
 319     ssize_t tmp;
 320 
 321     top = mc_read (arch->fd, buf, sizeof (buf));
 322     if (top > 0)
 323         CPIO_POS (super) += top;
 324 
 325     while (TRUE)
 326     {
 327         if (ptr + MAGIC_LENGTH >= top)
 328         {
 329             if (top > (ssize_t) (sizeof (buf) / 2))
 330             {
 331                 memmove (buf, buf + top - sizeof (buf) / 2, sizeof (buf) / 2);
 332                 ptr -= top - sizeof (buf) / 2;
 333                 top = sizeof (buf) / 2;
 334             }
 335             tmp = mc_read (arch->fd, buf, top);
 336             if (tmp == 0 || tmp == -1)
 337             {
 338                 message (D_ERROR, MSG_ERROR, _ ("Premature end of cpio archive\n%s"), super->name);
 339                 cpio_free_archive (me, super);
 340                 return CPIO_UNKNOWN;
 341             }
 342             top += tmp;
 343         }
 344         if (TYPEIS (CPIO_BIN) && ((*(unsigned short *) (buf + ptr)) == 070707))
 345         {
 346             SEEKBACK;
 347             RETURN (CPIO_BIN);
 348         }
 349         else if (TYPEIS (CPIO_BINRE)
 350                  && ((*(unsigned short *) (buf + ptr)) == GUINT16_SWAP_LE_BE_CONSTANT (070707)))
 351         {
 352             SEEKBACK;
 353             RETURN (CPIO_BINRE);
 354         }
 355         else if (TYPEIS (CPIO_OLDC) && (strncmp (buf + ptr, "070707", 6) == 0))
 356         {
 357             SEEKBACK;
 358             RETURN (CPIO_OLDC);
 359         }
 360         else if (TYPEIS (CPIO_NEWC) && (strncmp (buf + ptr, "070701", 6) == 0))
 361         {
 362             SEEKBACK;
 363             RETURN (CPIO_NEWC);
 364         }
 365         else if (TYPEIS (CPIO_CRC) && (strncmp (buf + ptr, "070702", 6) == 0))
 366         {
 367             SEEKBACK;
 368             RETURN (CPIO_CRC);
 369         };
 370         ptr++;
 371     }
 372 }
 373 
 374 /* --------------------------------------------------------------------------------------------- */
 375 
 376 static int
 377 cpio_create_entry (struct vfs_class *me, struct vfs_s_super *super, struct stat *st, char *name)
     /*   */
 378 {
 379     cpio_super_t *arch = CPIO_SUPER (super);
 380     struct vfs_s_inode *inode = NULL;
 381     struct vfs_s_inode *root = super->root;
 382     struct vfs_s_entry *entry = NULL;
 383     char *tn;
 384 
 385     switch (st->st_mode & S_IFMT)
 386     {  // For case of HP/UX archives
 387     case S_IFCHR:
 388     case S_IFBLK:
 389 #ifdef S_IFSOCK
 390         // cppcheck-suppress syntaxError
 391     case S_IFSOCK:
 392 #endif
 393 #ifdef S_IFIFO
 394         // cppcheck-suppress syntaxError
 395     case S_IFIFO:
 396 #endif
 397 #ifdef S_IFNAM
 398         // cppcheck-suppress syntaxError
 399     case S_IFNAM:
 400 #endif
 401 #ifdef HAVE_STRUCT_STAT_ST_RDEV
 402         if ((st->st_size != 0) && (st->st_rdev == 0x0001))
 403         {
 404             // FIXME: representation of major/minor differs between different operating systems
 405             st->st_rdev = (unsigned) st->st_size;
 406             st->st_size = 0;
 407         }
 408 #endif
 409         break;
 410     default:
 411         break;
 412     }
 413 
 414     if ((st->st_nlink > 1) && ((arch->type == CPIO_NEWC) || (arch->type == CPIO_CRC)))
 415     {  // For case of hardlinked files
 416         defer_inode i = { st->st_ino, st->st_dev, NULL };
 417         GSList *l;
 418 
 419         l = g_slist_find_custom (arch->deferred, &i, cpio_defer_find);
 420         if (l != NULL)
 421         {
 422             inode = ((defer_inode *) l->data)->inode;
 423             if (inode->st.st_size != 0 && st->st_size != 0 && (inode->st.st_size != st->st_size))
 424             {
 425                 message (D_ERROR, MSG_ERROR,
 426                          _ ("Inconsistent hardlinks of\n%s\nin cpio archive\n%s"), name,
 427                          super->name);
 428                 inode = NULL;
 429             }
 430             else if (inode->st.st_size == 0)
 431                 inode->st.st_size = st->st_size;
 432         }
 433     }
 434 
 435     // remove trailing slashes
 436     for (tn = name + strlen (name) - 1; tn >= name && IS_PATH_SEP (*tn); tn--)
 437         *tn = '\0';
 438 
 439     tn = strrchr (name, PATH_SEP);
 440     if (tn == NULL)
 441         tn = name;
 442     else if (tn == name + 1)
 443     {
 444         // started with "./" -- directory in the root of archive
 445         tn++;
 446     }
 447     else
 448     {
 449         *tn = '\0';
 450         root = vfs_s_find_inode (me, super, name, LINK_FOLLOW, FL_MKDIR);
 451         *tn = PATH_SEP;
 452         tn++;
 453     }
 454 
 455     entry = VFS_SUBCLASS (me)->find_entry (me, root, tn, LINK_FOLLOW,
 456                                            FL_NONE);  // In case entry is already there
 457 
 458     if (entry != NULL)
 459     {
 460         /* This shouldn't happen! (well, it can happen if there is a record for a
 461            file and then a record for a directory it is in; cpio would die with
 462            'No such file or directory' is such case) */
 463 
 464         if (!S_ISDIR (entry->ino->st.st_mode))
 465         {
 466             // This can be considered archive inconsistency
 467             message (D_ERROR, MSG_ERROR, _ ("%s contains duplicate entries! Skipping!"),
 468                      super->name);
 469         }
 470         else
 471         {
 472             entry->ino->st.st_mode = st->st_mode;
 473             entry->ino->st.st_uid = st->st_uid;
 474             entry->ino->st.st_gid = st->st_gid;
 475 
 476             vfs_copy_stat_times (st, &entry->ino->st);
 477         }
 478 
 479         g_free (name);
 480     }
 481     else
 482     {  // !entry
 483         /* root == NULL can be in the following case:
 484          * a/b/c -> d
 485          * where 'a/b' is the stale link and therefore root of 'c' cannot be found in the archive
 486          */
 487         if (root != NULL)
 488         {
 489             if (inode == NULL)
 490             {
 491                 inode = vfs_s_new_inode (me, super, st);
 492                 if ((st->st_nlink > 0) && ((arch->type == CPIO_NEWC) || (arch->type == CPIO_CRC)))
 493                 {
 494                     // For case of hardlinked files
 495                     defer_inode *i;
 496 
 497                     i = g_new (defer_inode, 1);
 498                     i->inumber = st->st_ino;
 499                     i->device = st->st_dev;
 500                     i->inode = inode;
 501 
 502                     arch->deferred = g_slist_prepend (arch->deferred, i);
 503                 }
 504             }
 505 
 506             if (st->st_size != 0)
 507                 inode->data_offset = CPIO_POS (super);
 508 
 509             entry = vfs_s_new_entry (me, tn, inode);
 510             vfs_s_insert_entry (me, root, entry);
 511         }
 512 
 513         g_free (name);
 514 
 515         if (!S_ISLNK (st->st_mode))
 516             CPIO_SEEK_CUR (super, st->st_size);
 517         else
 518         {
 519             if (inode != NULL)
 520             {
 521                 // FIXME: do we must read from arch->fd in case of inode != NULL only or in any
 522                 // case?
 523 
 524                 inode->linkname = g_malloc (st->st_size + 1);
 525 
 526                 if (mc_read (arch->fd, inode->linkname, st->st_size) < st->st_size)
 527                 {
 528                     inode->linkname[0] = '\0';
 529                     return STATUS_EOF;
 530                 }
 531 
 532                 inode->linkname[st->st_size] = '\0';  // Linkname stored without terminating \0 !!!
 533             }
 534 
 535             CPIO_POS (super) += st->st_size;
 536             cpio_skip_padding (super);
 537         }
 538     }  // !entry
 539 
 540     return STATUS_OK;
 541 }
 542 
 543 /* --------------------------------------------------------------------------------------------- */
 544 
 545 static ssize_t
 546 cpio_read_bin_head (struct vfs_class *me, struct vfs_s_super *super)
     /*   */
 547 {
 548     union
 549     {
 550         struct old_cpio_header buf;
 551         short shorts[HEAD_LENGTH >> 1];
 552     } u;
 553 
 554     cpio_super_t *arch = CPIO_SUPER (super);
 555     ssize_t len;
 556     char *name;
 557     struct stat st;
 558 
 559     len = mc_read (arch->fd, (char *) &u.buf, HEAD_LENGTH);
 560     if (len < HEAD_LENGTH)
 561         return STATUS_EOF;
 562     CPIO_POS (super) += len;
 563     if (arch->type == CPIO_BINRE)
 564     {
 565         int i;
 566 
 567         for (i = 0; i < (HEAD_LENGTH >> 1); i++)
 568             u.shorts[i] = GUINT16_SWAP_LE_BE_CONSTANT (u.shorts[i]);
 569     }
 570 
 571     if (u.buf.c_magic != 070707 || u.buf.c_namesize == 0 || u.buf.c_namesize > MC_MAXPATHLEN)
 572     {
 573         message (D_ERROR, MSG_ERROR, _ ("Corrupted cpio header encountered in\n%s"), super->name);
 574         return STATUS_FAIL;
 575     }
 576     name = g_malloc (u.buf.c_namesize);
 577     len = mc_read (arch->fd, name, u.buf.c_namesize);
 578     if (len < u.buf.c_namesize)
 579     {
 580         g_free (name);
 581         return STATUS_EOF;
 582     }
 583     name[u.buf.c_namesize - 1] = '\0';
 584     CPIO_POS (super) += len;
 585     cpio_skip_padding (super);
 586 
 587     if (strcmp ("TRAILER!!!", name) == 0)
 588     {  // We got to the last record
 589         g_free (name);
 590         return STATUS_TRAIL;
 591     }
 592 
 593     st.st_dev = u.buf.c_dev;
 594     st.st_ino = u.buf.c_ino;
 595     st.st_mode = u.buf.c_mode;
 596     st.st_nlink = u.buf.c_nlink;
 597     st.st_uid = u.buf.c_uid;
 598     st.st_gid = u.buf.c_gid;
 599 #ifdef HAVE_STRUCT_STAT_ST_RDEV
 600     st.st_rdev = u.buf.c_rdev;
 601 #endif
 602     st.st_size = ((off_t) u.buf.c_filesizes[0] << 16) | u.buf.c_filesizes[1];
 603 
 604     vfs_zero_stat_times (&st);
 605 
 606     st.st_atime = st.st_mtime = st.st_ctime =
 607         ((time_t) u.buf.c_mtimes[0] << 16) | u.buf.c_mtimes[1];
 608 
 609     return cpio_create_entry (me, super, &st, name);
 610 }
 611 
 612 /* --------------------------------------------------------------------------------------------- */
 613 
 614 #undef HEAD_LENGTH
 615 #define HEAD_LENGTH (76)
 616 
 617 static ssize_t
 618 cpio_read_oldc_head (struct vfs_class *me, struct vfs_s_super *super)
     /*   */
 619 {
 620     cpio_super_t *arch = CPIO_SUPER (super);
 621     struct new_cpio_header hd;
 622     union
 623     {
 624         struct stat st;
 625         char buf[HEAD_LENGTH + 1];
 626     } u;
 627     ssize_t len;
 628     char *name;
 629 
 630     if (mc_read (arch->fd, u.buf, HEAD_LENGTH) != HEAD_LENGTH)
 631         return STATUS_EOF;
 632     CPIO_POS (super) += HEAD_LENGTH;
 633     u.buf[HEAD_LENGTH] = 0;
 634 
 635     if (sscanf (u.buf, "070707%6lo%6lo%6lo%6lo%6lo%6lo%6lo%11lo%6lo%11lo",
 636                 (unsigned long *) &hd.c_dev, &hd.c_ino, &hd.c_mode, &hd.c_uid, &hd.c_gid,
 637                 &hd.c_nlink, (unsigned long *) &hd.c_rdev, &hd.c_mtime, &hd.c_namesize,
 638                 &hd.c_filesize)
 639         < 10)
 640     {
 641         message (D_ERROR, MSG_ERROR, _ ("Corrupted cpio header encountered in\n%s"), super->name);
 642         return STATUS_FAIL;
 643     }
 644 
 645     if (hd.c_namesize == 0 || hd.c_namesize > MC_MAXPATHLEN)
 646     {
 647         message (D_ERROR, MSG_ERROR, _ ("Corrupted cpio header encountered in\n%s"), super->name);
 648         return STATUS_FAIL;
 649     }
 650     name = g_malloc (hd.c_namesize);
 651     len = mc_read (arch->fd, name, hd.c_namesize);
 652     if ((len == -1) || ((unsigned long) len < hd.c_namesize))
 653     {
 654         g_free (name);
 655         return STATUS_EOF;
 656     }
 657     name[hd.c_namesize - 1] = '\0';
 658     CPIO_POS (super) += len;
 659     cpio_skip_padding (super);
 660 
 661     if (strcmp ("TRAILER!!!", name) == 0)
 662     {  // We got to the last record
 663         g_free (name);
 664         return STATUS_TRAIL;
 665     }
 666 
 667     u.st.st_dev = hd.c_dev;
 668     u.st.st_ino = hd.c_ino;
 669     u.st.st_mode = hd.c_mode;
 670     u.st.st_nlink = hd.c_nlink;
 671     u.st.st_uid = hd.c_uid;
 672     u.st.st_gid = hd.c_gid;
 673 #ifdef HAVE_STRUCT_STAT_ST_RDEV
 674     u.st.st_rdev = hd.c_rdev;
 675 #endif
 676     u.st.st_size = hd.c_filesize;
 677 
 678     vfs_zero_stat_times (&u.st);
 679     u.st.st_atime = u.st.st_mtime = u.st.st_ctime = hd.c_mtime;
 680 
 681     return cpio_create_entry (me, super, &u.st, name);
 682 }
 683 
 684 /* --------------------------------------------------------------------------------------------- */
 685 
 686 #undef HEAD_LENGTH
 687 #define HEAD_LENGTH (110)
 688 
 689 static ssize_t
 690 cpio_read_crc_head (struct vfs_class *me, struct vfs_s_super *super)
     /*   */
 691 {
 692     cpio_super_t *arch = CPIO_SUPER (super);
 693     struct new_cpio_header hd;
 694     union
 695     {
 696         struct stat st;
 697         char buf[HEAD_LENGTH + 1];
 698     } u;
 699     ssize_t len;
 700     char *name;
 701 
 702     if (mc_read (arch->fd, u.buf, HEAD_LENGTH) != HEAD_LENGTH)
 703         return STATUS_EOF;
 704 
 705     CPIO_POS (super) += HEAD_LENGTH;
 706     u.buf[HEAD_LENGTH] = '\0';
 707 
 708     if (sscanf (u.buf, "%6ho%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx", &hd.c_magic,
 709                 &hd.c_ino, &hd.c_mode, &hd.c_uid, &hd.c_gid, &hd.c_nlink, &hd.c_mtime,
 710                 &hd.c_filesize, (unsigned long *) &hd.c_dev, (unsigned long *) &hd.c_devmin,
 711                 (unsigned long *) &hd.c_rdev, (unsigned long *) &hd.c_rdevmin, &hd.c_namesize,
 712                 &hd.c_chksum)
 713         < 14)
 714     {
 715         message (D_ERROR, MSG_ERROR, _ ("Corrupted cpio header encountered in\n%s"), super->name);
 716         return STATUS_FAIL;
 717     }
 718 
 719     if ((arch->type == CPIO_NEWC && hd.c_magic != 070701)
 720         || (arch->type == CPIO_CRC && hd.c_magic != 070702))
 721         return STATUS_FAIL;
 722 
 723     if (hd.c_namesize == 0 || hd.c_namesize > MC_MAXPATHLEN)
 724     {
 725         message (D_ERROR, MSG_ERROR, _ ("Corrupted cpio header encountered in\n%s"), super->name);
 726         return STATUS_FAIL;
 727     }
 728 
 729     name = g_malloc (hd.c_namesize);
 730     len = mc_read (arch->fd, name, hd.c_namesize);
 731 
 732     if ((len == -1) || ((unsigned long) len < hd.c_namesize))
 733     {
 734         g_free (name);
 735         return STATUS_EOF;
 736     }
 737     name[hd.c_namesize - 1] = '\0';
 738     CPIO_POS (super) += len;
 739     cpio_skip_padding (super);
 740 
 741     if (strcmp ("TRAILER!!!", name) == 0)
 742     {  // We got to the last record
 743         g_free (name);
 744         return STATUS_TRAIL;
 745     }
 746 
 747     u.st.st_dev = makedev (hd.c_dev, hd.c_devmin);
 748     u.st.st_ino = hd.c_ino;
 749     u.st.st_mode = hd.c_mode;
 750     u.st.st_nlink = hd.c_nlink;
 751     u.st.st_uid = hd.c_uid;
 752     u.st.st_gid = hd.c_gid;
 753 #ifdef HAVE_STRUCT_STAT_ST_RDEV
 754     u.st.st_rdev = makedev (hd.c_rdev, hd.c_rdevmin);
 755 #endif
 756     u.st.st_size = hd.c_filesize;
 757 
 758     vfs_zero_stat_times (&u.st);
 759     u.st.st_atime = u.st.st_mtime = u.st.st_ctime = hd.c_mtime;
 760 
 761     return cpio_create_entry (me, super, &u.st, name);
 762 }
 763 
 764 /* --------------------------------------------------------------------------------------------- */
 765 /** Need to CPIO_SEEK_CUR to skip the file at the end of add entry!!!! */
 766 
 767 static int
 768 cpio_open_archive (struct vfs_s_super *super, const vfs_path_t *vpath,
     /*   */
 769                    const vfs_path_element_t *vpath_element)
 770 {
 771     (void) vpath_element;
 772 
 773     if (cpio_open_cpio_file (vpath_element->class, super, vpath) == -1)
 774         return -1;
 775 
 776     while (TRUE)
 777     {
 778         ssize_t status;
 779 
 780         status = cpio_read_head (vpath_element->class, super);
 781         if (status < 0)
 782             return (-1);
 783 
 784         switch (status)
 785         {
 786         case STATUS_EOF:
 787         {
 788             message (D_ERROR, MSG_ERROR, _ ("Unexpected end of file\n%s"), vfs_path_as_str (vpath));
 789             return 0;
 790         }
 791         case STATUS_OK:
 792             continue;
 793         case STATUS_TRAIL:
 794             break;
 795         default:
 796             break;
 797         }
 798         break;
 799     }
 800 
 801     return 0;
 802 }
 803 
 804 /* --------------------------------------------------------------------------------------------- */
 805 /** Remaining functions are exactly same as for tarfs (and were in fact just copied) */
 806 
 807 static void *
 808 cpio_super_check (const vfs_path_t *vpath)
     /*   */
 809 {
 810     static struct stat sb;
 811     int stat_result;
 812 
 813     stat_result = mc_stat (vpath, &sb);
 814     return (stat_result == 0 ? &sb : NULL);
 815 }
 816 
 817 /* --------------------------------------------------------------------------------------------- */
 818 
 819 static int
 820 cpio_super_same (const vfs_path_element_t *vpath_element, struct vfs_s_super *parc,
     /*   */
 821                  const vfs_path_t *vpath, void *cookie)
 822 {
 823     struct stat *archive_stat = cookie;  // stat of main archive
 824 
 825     (void) vpath_element;
 826 
 827     if (strcmp (parc->name, vfs_path_as_str (vpath)))
 828         return 0;
 829 
 830     // Has the cached archive been changed on the disk?
 831     if (parc != NULL && CPIO_SUPER (parc)->st.st_mtime < archive_stat->st_mtime)
 832     {
 833         // Yes, reload!
 834         vfs_cpiofs_ops->free ((vfsid) parc);
 835         vfs_rmstamp (vfs_cpiofs_ops, (vfsid) parc);
 836         return 2;
 837     }
 838 
 839     // Hasn't been modified, give it a new timeout
 840     vfs_stamp (vfs_cpiofs_ops, (vfsid) parc);
 841     return 1;
 842 }
 843 
 844 /* --------------------------------------------------------------------------------------------- */
 845 
 846 static ssize_t
 847 cpio_read (void *fh, char *buffer, size_t count)
     /*   */
 848 {
 849     vfs_file_handler_t *file = VFS_FILE_HANDLER (fh);
 850     struct vfs_class *me = VFS_FILE_HANDLER_SUPER (fh)->me;
 851     int fd = CPIO_SUPER (VFS_FILE_HANDLER_SUPER (fh))->fd;
 852     off_t begin = file->ino->data_offset;
 853     ssize_t res;
 854 
 855     if (mc_lseek (fd, begin + file->pos, SEEK_SET) != begin + file->pos)
 856         ERRNOR (EIO, -1);
 857 
 858     count = MIN (count, (size_t) (file->ino->st.st_size - file->pos));
 859 
 860     res = mc_read (fd, buffer, count);
 861     if (res == -1)
 862         ERRNOR (errno, -1);
 863 
 864     file->pos += res;
 865     return res;
 866 }
 867 
 868 /* --------------------------------------------------------------------------------------------- */
 869 
 870 static int
 871 cpio_fh_open (struct vfs_class *me, vfs_file_handler_t *fh, int flags, mode_t mode)
     /*   */
 872 {
 873     (void) fh;
 874     (void) mode;
 875 
 876     if ((flags & O_ACCMODE) != O_RDONLY)
 877         ERRNOR (EROFS, -1);
 878     return 0;
 879 }
 880 
 881 /* --------------------------------------------------------------------------------------------- */
 882 /*** public functions ****************************************************************************/
 883 /* --------------------------------------------------------------------------------------------- */
 884 
 885 void
 886 vfs_init_cpiofs (void)
     /*   */
 887 {
 888     // FIXME: cpiofs used own temp files
 889     vfs_init_subclass (&cpio_subclass, "cpiofs", VFSF_READONLY, "ucpio");
 890     vfs_cpiofs_ops->read = cpio_read;
 891     vfs_cpiofs_ops->setctl = NULL;
 892     cpio_subclass.archive_check = cpio_super_check;
 893     cpio_subclass.archive_same = cpio_super_same;
 894     cpio_subclass.new_archive = cpio_new_archive;
 895     cpio_subclass.open_archive = cpio_open_archive;
 896     cpio_subclass.free_archive = cpio_free_archive;
 897     cpio_subclass.fh_open = cpio_fh_open;
 898     vfs_register_class (vfs_cpiofs_ops);
 899 }
 900 
 901 /* --------------------------------------------------------------------------------------------- */
/* */
root/src/vfs/cpio/cpio.c

DEFINITIONS
