lib/vfs/mc-vfs/cpio.c

   1 /* Virtual File System: GNU Tar file system.
   2    Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2007
   3    Free Software Foundation, Inc.
   4
   5    Written by: 2000 Jan Hudec
   6
   7    This program is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Library General Public License
   9    as published by the Free Software Foundation; either version 2 of
  10    the License, or (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Library General Public
  18    License along with this program; if not, write to the Free Software
  19    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  20
  21 /** \file
  22  *  \brief Source: Virtual File System: GNU Tar file system.
  23  *  \author Jan Hudec
  24  *  \date 2000
  25  */
  26
  27 #include <config.h>
  28
  29 #include <errno.h>
  30 #include <fcntl.h>
  31
  32 #include "lib/global.h"
  33 #include "lib/unixcompat.h"
  34
  35 #include "src/wtools.h" /* message() */
  36 #include "src/main.h"   /* print_vfs_message */
  37 #include "vfs.h"
  38
  39 #include "utilvfs.h"
  40 #include "vfs-impl.h"
  41 #include "gc.h"                 /* vfs_rmstamp */
  42 #include "xdirentry.h"
  43
  44 enum {
  45     STATUS_START,
  46     STATUS_OK,
  47     STATUS_TRAIL,
  48     STATUS_FAIL,
  49     STATUS_EOF
  50 };
  51
  52 enum {
  53     CPIO_UNKNOWN = 0, /* Not determined yet */
  54     CPIO_BIN,         /* Binary format */
  55     CPIO_BINRE,       /* Binary format, reverse endianity */
  56     CPIO_OLDC,        /* Old ASCII format */
  57     CPIO_NEWC,        /* New ASCII format */
  58     CPIO_CRC          /* New ASCII format + CRC */
  59 };
  60
  61 static struct vfs_class vfs_cpiofs_ops;
  62
  63 struct old_cpio_header
  64 {
  65   unsigned short c_magic;
  66   short c_dev;
  67   unsigned short c_ino;
  68   unsigned short c_mode;
  69   unsigned short c_uid;
  70   unsigned short c_gid;
  71   unsigned short c_nlink;
  72   short c_rdev;
  73   unsigned short c_mtimes[2];
  74   unsigned short c_namesize;
  75   unsigned short c_filesizes[2];
  76 };
  77
  78 struct new_cpio_header
  79 {
  80   unsigned short c_magic;
  81   unsigned long c_ino;
  82   unsigned long c_mode;
  83   unsigned long c_uid;
  84   unsigned long c_gid;
  85   unsigned long c_nlink;
  86   unsigned long c_mtime;
  87   unsigned long c_filesize;
  88   long c_dev;
  89   long c_devmin;
  90   long c_rdev;
  91   long c_rdevmin;
  92   unsigned long c_namesize;
  93   unsigned long c_chksum;
  94 };
  95
  96 struct defer_inode {
  97     struct defer_inode *next;
  98     unsigned long inumber;
  99     unsigned short device;
 100     struct vfs_s_inode *inode;
 101 };
 102
 103 /* FIXME: should be off_t instead of int. */
 104 static int cpio_position;
 105
 106 static int cpio_find_head(struct vfs_class *me, struct vfs_s_super *super);
 107 static ssize_t cpio_read_bin_head(struct vfs_class *me, struct vfs_s_super *super);
 108 static ssize_t cpio_read_oldc_head(struct vfs_class *me, struct vfs_s_super *super);
 109 static ssize_t cpio_read_crc_head(struct vfs_class *me, struct vfs_s_super *super);
 110 static ssize_t cpio_read(void *fh, char *buffer, int count);
 111
 112 #define CPIO_POS(super) cpio_position
 113 /* If some time reentrancy should be needed change it to */
 114 /* #define CPIO_POS(super) (super)->u.arch.fd */
 115
 116 #define CPIO_SEEK_SET(super, where) mc_lseek((super)->u.arch.fd, CPIO_POS(super) = (where), SEEK_SET)
 117 #define CPIO_SEEK_CUR(super, where) mc_lseek((super)->u.arch.fd, CPIO_POS(super) += (where), SEEK_SET)
 118
 119 static struct defer_inode *
 120 cpio_defer_find (struct defer_inode *l, struct defer_inode *i)
 121 {
 122     while (l && (l->inumber != i->inumber || l->device != i->device))
 123         l = l->next;
 124     return l;
 125 }
 126
 127 static int cpio_skip_padding(struct vfs_s_super *super)
 128 {
 129     switch(super->u.arch.type) {
 130     case CPIO_BIN:
 131     case CPIO_BINRE:
 132         return CPIO_SEEK_CUR(super, (2 - (CPIO_POS(super) % 2)) % 2);
 133     case CPIO_NEWC:
 134     case CPIO_CRC:
 135         return CPIO_SEEK_CUR(super, (4 - (CPIO_POS(super) % 4)) % 4);
 136     case CPIO_OLDC:
 137         return CPIO_POS(super);
 138     default:
 139         g_assert_not_reached();
 140         return 42; /* & the compiler is happy :-) */
 141     }
 142 }
 143
 144 static void cpio_free_archive(struct vfs_class *me, struct vfs_s_super *super)
 145 {
 146     struct defer_inode *l, *lnext;
 147
 148     (void) me;
 149
 150     if(super->u.arch.fd != -1)
 151         mc_close(super->u.arch.fd);
 152         super->u.arch.fd = -1;
 153     for (l = super->u.arch.deferred; l; l = lnext) {
 154         lnext = l->next;
 155         g_free (l);
 156     }
 157     super->u.arch.deferred = NULL;
 158 }
 159
 160 static int
 161 cpio_open_cpio_file (struct vfs_class *me, struct vfs_s_super *super,
 162                      const char *name)
 163 {
 164     int fd, type;
 165     mode_t mode;
 166     struct vfs_s_inode *root;
 167
 168     if ((fd = mc_open (name, O_RDONLY)) == -1) {
 169         message (D_ERROR, MSG_ERROR, _("Cannot open cpio archive\n%s"), name);
 170         return -1;
 171     }
 172
 173     super->name = g_strdup (name);
 174     super->u.arch.fd = -1;      /* for now */
 175     mc_stat (name, &(super->u.arch.st));
 176     super->u.arch.type = CPIO_UNKNOWN;
 177
 178     type = get_compression_type (fd, name);
 179     if (type != COMPRESSION_NONE) {
 180         char *s;
 181
 182         mc_close (fd);
 183         s = g_strconcat (name, decompress_extension (type), (char *) NULL);
 184         if ((fd = mc_open (s, O_RDONLY)) == -1) {
 185             message (D_ERROR, MSG_ERROR, _("Cannot open cpio archive\n%s"), s);
 186             g_free (s);
 187             return -1;
 188         }
 189         g_free (s);
 190     }
 191
 192     super->u.arch.fd = fd;
 193     mode = super->u.arch.st.st_mode & 07777;
 194     mode |= (mode & 0444) >> 2; /* set eXec where Read is */
 195     mode |= S_IFDIR;
 196
 197     root = vfs_s_new_inode (me, super, &(super->u.arch.st));
 198     root->st.st_mode = mode;
 199     root->data_offset = -1;
 200     root->st.st_nlink++;
 201     root->st.st_dev = MEDATA->rdev++;
 202
 203     super->root = root;
 204
 205     CPIO_SEEK_SET (super, 0);
 206
 207     return fd;
 208 }
 209
 210 static ssize_t cpio_read_head(struct vfs_class *me, struct vfs_s_super *super)
 211 {
 212     switch(cpio_find_head(me, super)) {
 213     case CPIO_UNKNOWN:
 214         return -1;
 215     case CPIO_BIN:
 216     case CPIO_BINRE:
 217         return cpio_read_bin_head(me, super);
 218     case CPIO_OLDC:
 219         return cpio_read_oldc_head(me, super);
 220     case CPIO_NEWC:
 221     case CPIO_CRC:
 222         return cpio_read_crc_head(me, super);
 223     default:
 224         g_assert_not_reached();
 225         return 42; /* & the compiler is happy :-) */
 226     }
 227 }
 228
 229 #define MAGIC_LENGTH (6) /* How many bytes we have to read ahead */
 230 #define SEEKBACK CPIO_SEEK_CUR(super, ptr - top)
 231 #define RETURN(x) return(super->u.arch.type = (x))
 232 #define TYPEIS(x) ((super->u.arch.type == CPIO_UNKNOWN) || (super->u.arch.type == (x)))
 233 static int cpio_find_head(struct vfs_class *me, struct vfs_s_super *super)
 234 {
 235     char buf[256];
 236     int ptr = 0;
 237     ssize_t top;
 238     ssize_t tmp;
 239
 240     top = mc_read (super->u.arch.fd, buf, 256);
 241     if (top > 0)
 242         CPIO_POS (super) += top;
 243     for(;;) {
 244         if(ptr + MAGIC_LENGTH >= top) {
 245             if(top > 128) {
 246                 memmove(buf, buf + top - 128, 128);
 247                 ptr -= top - 128;
 248                 top = 128;
 249             }
 250             if((tmp = mc_read(super->u.arch.fd, buf, top)) == 0 || tmp == -1) {
 251                 message (D_ERROR, MSG_ERROR, _("Premature end of cpio archive\n%s"), super->name);
 252                 cpio_free_archive(me, super);
 253                 return CPIO_UNKNOWN;
 254             }
 255             top += tmp;
 256         }
 257         if(TYPEIS(CPIO_BIN) && ((*(unsigned short *)(buf + ptr)) == 070707)) {
 258             SEEKBACK; RETURN(CPIO_BIN);
 259         } else if(TYPEIS(CPIO_BINRE) && ((*(unsigned short *)(buf + ptr)) == GUINT16_SWAP_LE_BE_CONSTANT(070707))) {
 260             SEEKBACK; RETURN(CPIO_BINRE);
 261         } else if(TYPEIS(CPIO_OLDC) && (!strncmp(buf + ptr, "070707", 6))) {
 262             SEEKBACK; RETURN(CPIO_OLDC);
 263         } else if(TYPEIS(CPIO_NEWC) && (!strncmp(buf + ptr, "070701", 6))) {
 264             SEEKBACK; RETURN(CPIO_NEWC);
 265         } else if(TYPEIS(CPIO_CRC) && (!strncmp(buf + ptr, "070702", 6))) {
 266             SEEKBACK; RETURN(CPIO_CRC);
 267         };
 268         ptr++;
 269     }
 270 }
 271 #undef RETURN
 272 #undef SEEKBACK
 273
 274 static int
 275 cpio_create_entry (struct vfs_class *me, struct vfs_s_super *super,
 276                    struct stat *st, char *name)
 277 {
 278     struct vfs_s_inode *inode = NULL;
 279     struct vfs_s_inode *root = super->root;
 280     struct vfs_s_entry *entry = NULL;
 281     char *tn;
 282
 283     switch (st->st_mode & S_IFMT) {     /* For case of HP/UX archives */
 284     case S_IFCHR:
 285     case S_IFBLK:
 286 #ifdef S_IFSOCK
 287     case S_IFSOCK:
 288 #endif
 289 #ifdef S_IFIFO
 290     case S_IFIFO:
 291 #endif
 292 #ifdef S_IFNAM
 293     case S_IFNAM:
 294 #endif
 295         if ((st->st_size != 0) && (st->st_rdev == 0x0001)) {
 296             /* FIXME: representation of major/minor differs between */
 297             /* different operating systems. */
 298             st->st_rdev = (unsigned) st->st_size;
 299             st->st_size = 0;
 300         }
 301         break;
 302     default:
 303         break;
 304     }
 305
 306     if ((st->st_nlink > 1)
 307              && ((super->u.arch.type == CPIO_NEWC)
 308                     || (super->u.arch.type == CPIO_CRC))) {     /* For case of hardlinked files */
 309         struct defer_inode i, *l;
 310         i.inumber = st->st_ino;
 311         i.device = st->st_dev;
 312         i.inode = NULL;
 313
 314         l = cpio_defer_find (super->u.arch.deferred, &i);
 315         if (l != NULL) {
 316             inode = l->inode;
 317             if (inode->st.st_size != 0 && st->st_size != 0
 318                     && (inode->st.st_size != st->st_size)) {
 319                 message (D_ERROR, MSG_ERROR,
 320                         _("Inconsistent hardlinks of\n%s\nin cpio archive\n%s"),
 321                         name, super->name);
 322                 inode = NULL;
 323             } else if (inode->st.st_size == 0)
 324                 inode->st.st_size = st->st_size;
 325         }
 326     }
 327
 328     /* remove trailing slashes */
 329     for (tn = name + strlen (name) - 1; tn >= name && *tn == PATH_SEP; tn--)
 330         *tn = '\0';
 331
 332     tn = strrchr (name, PATH_SEP);
 333     if (tn == NULL)
 334         tn = name;
 335     else if (tn == name + 1) {
 336         /* started with "./" -- directory in the root of archive */
 337         tn++;
 338     } else {
 339         *tn = '\0';
 340         root = vfs_s_find_inode (me, super, name, LINK_FOLLOW, FL_MKDIR);
 341         *tn = PATH_SEP;
 342         tn++;
 343     }
 344
 345     entry = MEDATA->find_entry (me, root, tn, LINK_FOLLOW, FL_NONE);    /* In case entry is already there */
 346
 347     if (entry != NULL) {
 348         /* This shouldn't happen! (well, it can happen if there is a record for a
 349            file and than a record for a directory it is in; cpio would die with
 350            'No such file or directory' is such case) */
 351
 352         if (!S_ISDIR (entry->ino->st.st_mode)) {
 353             /* This can be considered archive inconsistency */
 354             message (D_ERROR, MSG_ERROR,
 355                      _("%s contains duplicate entries! Skipping!"),
 356                      super->name);
 357         } else {
 358             entry->ino->st.st_mode = st->st_mode;
 359             entry->ino->st.st_uid = st->st_uid;
 360             entry->ino->st.st_gid = st->st_gid;
 361             entry->ino->st.st_atime = st->st_atime;
 362             entry->ino->st.st_mtime = st->st_mtime;
 363             entry->ino->st.st_ctime = st->st_ctime;
 364         }
 365
 366         g_free (name);
 367     } else {                    /* !entry */
 368         if (inode == NULL) {
 369             inode = vfs_s_new_inode (me, super, st);
 370             if ((st->st_nlink > 0)
 371                      && ((super->u.arch.type == CPIO_NEWC)
 372                             || (super->u.arch.type == CPIO_CRC))) {
 373                 /* For case of hardlinked files */
 374                 struct defer_inode *i;
 375                 i = g_new (struct defer_inode, 1);
 376                 i->inumber = st->st_ino;
 377                 i->device = st->st_dev;
 378                 i->inode = inode;
 379                 i->next = super->u.arch.deferred;
 380                 super->u.arch.deferred = i;
 381             }
 382         }
 383
 384         if (st->st_size != 0)
 385             inode->data_offset = CPIO_POS (super);
 386
 387         entry = vfs_s_new_entry (me, tn, inode);
 388         vfs_s_insert_entry (me, root, entry);
 389
 390         g_free (name);
 391
 392         if (!S_ISLNK (st->st_mode))
 393             CPIO_SEEK_CUR (super, st->st_size);
 394         else {
 395             inode->linkname = g_malloc (st->st_size + 1);
 396
 397             if (mc_read (super->u.arch.fd, inode->linkname, st->st_size) < st->st_size) {
 398                 inode->linkname[0] = '\0';
 399                 return STATUS_EOF;
 400             }
 401
 402             inode->linkname[st->st_size] = '\0';        /* Linkname stored without terminating \0 !!! */
 403             CPIO_POS (super) += st->st_size;
 404             cpio_skip_padding (super);
 405         }
 406     }                           /* !entry */
 407
 408     return STATUS_OK;
 409 }
 410
 411 #define HEAD_LENGTH (26)
 412 static ssize_t cpio_read_bin_head(struct vfs_class *me, struct vfs_s_super *super)
 413 {
 414     union {
 415         struct old_cpio_header buf;
 416         short shorts[HEAD_LENGTH >> 1];
 417     } u;
 418     ssize_t len;
 419     char *name;
 420     struct stat st;
 421
 422     if((len = mc_read(super->u.arch.fd, (char *)&u.buf, HEAD_LENGTH)) < HEAD_LENGTH)
 423         return STATUS_EOF;
 424     CPIO_POS(super) += len;
 425     if(super->u.arch.type == CPIO_BINRE) {
 426         int i;
 427         for(i = 0; i < (HEAD_LENGTH >> 1); i++)
 428             u.shorts[i] = GUINT16_SWAP_LE_BE_CONSTANT(u.shorts[i]);
 429     }
 430
 431     if (u.buf.c_magic != 070707 ||
 432         u.buf.c_namesize == 0 || u.buf.c_namesize > MC_MAXPATHLEN) {
 433         message (D_ERROR, MSG_ERROR, _("Corrupted cpio header encountered in\n%s"),
 434                 super->name);
 435         return STATUS_FAIL;
 436     }
 437     name = g_malloc(u.buf.c_namesize);
 438     if((len = mc_read(super->u.arch.fd, name, u.buf.c_namesize)) < u.buf.c_namesize) {
 439         g_free(name);
 440         return STATUS_EOF;
 441     }
 442     name[u.buf.c_namesize - 1] = '\0';
 443     CPIO_POS(super) += len;
 444     cpio_skip_padding(super);
 445
 446     if(!strcmp("TRAILER!!!", name)) { /* We got to the last record */
 447         g_free(name);
 448         return STATUS_TRAIL;
 449     }
 450
 451     st.st_dev = u.buf.c_dev;
 452     st.st_ino = u.buf.c_ino;
 453     st.st_mode = u.buf.c_mode;
 454     st.st_nlink = u.buf.c_nlink;
 455     st.st_uid = u.buf.c_uid;
 456     st.st_gid = u.buf.c_gid;
 457     st.st_rdev = u.buf.c_rdev;
 458     st.st_size = (u.buf.c_filesizes[0] << 16) | u.buf.c_filesizes[1];
 459     st.st_atime = st.st_mtime = st.st_ctime = (u.buf.c_mtimes[0] << 16) | u.buf.c_mtimes[1];
 460
 461     return cpio_create_entry(me, super, &st, name);
 462 }
 463 #undef HEAD_LENGTH
 464
 465 #define HEAD_LENGTH (76)
 466 static ssize_t cpio_read_oldc_head(struct vfs_class *me, struct vfs_s_super *super)
 467 {
 468     struct new_cpio_header hd;
 469     union {
 470         struct stat st;
 471         char buf[HEAD_LENGTH + 1];
 472     } u;
 473     ssize_t len;
 474     char *name;
 475
 476     if (mc_read (super->u.arch.fd, u.buf, HEAD_LENGTH) != HEAD_LENGTH)
 477         return STATUS_EOF;
 478     CPIO_POS (super) += HEAD_LENGTH;
 479     u.buf[HEAD_LENGTH] = 0;
 480
 481     if (sscanf (u.buf, "070707%6lo%6lo%6lo%6lo%6lo%6lo%6lo%11lo%6lo%11lo",
 482               (unsigned long *)&hd.c_dev, &hd.c_ino, &hd.c_mode, &hd.c_uid, &hd.c_gid,
 483               &hd.c_nlink, (unsigned long *)&hd.c_rdev, &hd.c_mtime,
 484               &hd.c_namesize, &hd.c_filesize) < 10) {
 485         message (D_ERROR, MSG_ERROR, _("Corrupted cpio header encountered in\n%s"),
 486                     super->name);
 487         return STATUS_FAIL;
 488     }
 489
 490     if (hd.c_namesize == 0 || hd.c_namesize > MC_MAXPATHLEN) {
 491         message (D_ERROR, MSG_ERROR, _("Corrupted cpio header encountered in\n%s"),
 492                     super->name);
 493         return STATUS_FAIL;
 494     }
 495     name = g_malloc(hd.c_namesize);
 496     if((len = mc_read(super->u.arch.fd, name, hd.c_namesize)) == -1 ||
 497        (unsigned long) len < hd.c_namesize) {
 498         g_free (name);
 499         return STATUS_EOF;
 500     }
 501     name[hd.c_namesize - 1] = '\0';
 502     CPIO_POS(super) +=  len;
 503     cpio_skip_padding(super);
 504
 505     if(!strcmp("TRAILER!!!", name)) { /* We got to the last record */
 506         g_free(name);
 507         return STATUS_TRAIL;
 508     }
 509
 510     u.st.st_dev = hd.c_dev;
 511     u.st.st_ino = hd.c_ino;
 512     u.st.st_mode = hd.c_mode;
 513     u.st.st_nlink = hd.c_nlink;
 514     u.st.st_uid = hd.c_uid;
 515     u.st.st_gid = hd.c_gid;
 516     u.st.st_rdev = hd.c_rdev;
 517     u.st.st_size = hd.c_filesize;
 518     u.st.st_atime = u.st.st_mtime = u.st.st_ctime = hd.c_mtime;
 519
 520     return cpio_create_entry (me, super, &u.st, name);
 521 }
 522 #undef HEAD_LENGTH
 523
 524 #define HEAD_LENGTH (110)
 525 static ssize_t
 526 cpio_read_crc_head (struct vfs_class *me, struct vfs_s_super *super)
 527 {
 528     struct new_cpio_header hd;
 529     union {
 530         struct stat st;
 531         char buf[HEAD_LENGTH + 1];
 532     } u;
 533     ssize_t len;
 534     char *name;
 535
 536     if (mc_read (super->u.arch.fd, u.buf, HEAD_LENGTH) != HEAD_LENGTH)
 537         return STATUS_EOF;
 538
 539     CPIO_POS (super) += HEAD_LENGTH;
 540     u.buf[HEAD_LENGTH] = '\0';
 541
 542     if (sscanf (u.buf, "%6ho%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx%8lx",
 543               &hd.c_magic, &hd.c_ino, &hd.c_mode, &hd.c_uid, &hd.c_gid,
 544               &hd.c_nlink,  &hd.c_mtime, &hd.c_filesize,
 545               (unsigned long *)&hd.c_dev, (unsigned long *)&hd.c_devmin,
 546               (unsigned long *)&hd.c_rdev, (unsigned long *)&hd.c_rdevmin,
 547               &hd.c_namesize, &hd.c_chksum) < 14) {
 548         message (D_ERROR, MSG_ERROR, _("Corrupted cpio header encountered in\n%s"),
 549                    super->name);
 550         return STATUS_FAIL;
 551     }
 552
 553     if((super->u.arch.type == CPIO_NEWC && hd.c_magic != 070701) ||
 554        (super->u.arch.type == CPIO_CRC && hd.c_magic != 070702))
 555         return STATUS_FAIL;
 556
 557     if (hd.c_namesize == 0 || hd.c_namesize > MC_MAXPATHLEN) {
 558         message (D_ERROR, MSG_ERROR, _("Corrupted cpio header encountered in\n%s"),
 559                     super->name);
 560         return STATUS_FAIL;
 561     }
 562
 563     name = g_malloc(hd.c_namesize);
 564     len = mc_read (super->u.arch.fd, name, hd.c_namesize);
 565
 566     if ((len == -1) || ((unsigned long) len < hd.c_namesize)) {
 567         g_free (name);
 568         return STATUS_EOF;
 569     }
 570     name[hd.c_namesize - 1] = '\0';
 571     CPIO_POS(super) += len;
 572     cpio_skip_padding(super);
 573
 574     if (strcmp ("TRAILER!!!", name) == 0) { /* We got to the last record */
 575         g_free(name);
 576         return STATUS_TRAIL;
 577     }
 578
 579     u.st.st_dev = makedev (hd.c_dev, hd.c_devmin);
 580     u.st.st_ino = hd.c_ino;
 581     u.st.st_mode = hd.c_mode;
 582     u.st.st_nlink = hd.c_nlink;
 583     u.st.st_uid = hd.c_uid;
 584     u.st.st_gid = hd.c_gid;
 585     u.st.st_rdev = makedev (hd.c_rdev, hd.c_rdevmin);
 586     u.st.st_size = hd.c_filesize;
 587     u.st.st_atime = u.st.st_mtime = u.st.st_ctime = hd.c_mtime;
 588
 589     return cpio_create_entry (me, super, &u.st, name);
 590 }
 591
 592 /* Need to CPIO_SEEK_CUR to skip the file at the end of add entry!!!! */
 593
 594 static int
 595 cpio_open_archive (struct vfs_class *me, struct vfs_s_super *super,
 596                    const char *name, char *op)
 597 {
 598     int status = STATUS_START;
 599
 600     (void) op;
 601
 602     if (cpio_open_cpio_file (me, super, name) == -1)
 603         return -1;
 604
 605     for (;;) {
 606         status = cpio_read_head (me, super);
 607
 608         switch (status) {
 609         case STATUS_EOF:
 610             message (D_ERROR, MSG_ERROR, _("Unexpected end of file\n%s"), name);
 611             return 0;
 612         case STATUS_OK:
 613             continue;
 614         case STATUS_TRAIL:
 615             break;
 616         }
 617         break;
 618     }
 619
 620     return 0;
 621 }
 622
 623 /* Remaining functions are exactly same as for tarfs (and were in fact just copied) */
 624 static void *
 625 cpio_super_check (struct vfs_class *me, const char *archive_name, char *op)
 626 {
 627     static struct stat sb;
 628
 629     (void) me;
 630     (void) op;
 631
 632     if (mc_stat (archive_name, &sb))
 633         return NULL;
 634     return &sb;
 635 }
 636
 637 static int
 638 cpio_super_same (struct vfs_class *me, struct vfs_s_super *parc,
 639                  const char *archive_name, char *op, void *cookie)
 640 {
 641     struct stat *archive_stat = cookie; /* stat of main archive */
 642
 643     (void) me;
 644     (void) op;
 645
 646     if (strcmp (parc->name, archive_name))
 647         return 0;
 648
 649     /* Has the cached archive been changed on the disk? */
 650     if (parc->u.arch.st.st_mtime < archive_stat->st_mtime) {
 651         /* Yes, reload! */
 652         (*vfs_cpiofs_ops.free) ((vfsid) parc);
 653         vfs_rmstamp (&vfs_cpiofs_ops, (vfsid) parc);
 654         return 2;
 655     }
 656     /* Hasn't been modified, give it a new timeout */
 657     vfs_stamp (&vfs_cpiofs_ops, (vfsid) parc);
 658     return 1;
 659 }
 660
 661 static ssize_t cpio_read(void *fh, char *buffer, int count)
 662 {
 663     off_t begin = FH->ino->data_offset;
 664     int fd = FH_SUPER->u.arch.fd;
 665     struct vfs_class *me = FH_SUPER->me;
 666
 667     if (mc_lseek (fd, begin + FH->pos, SEEK_SET) !=
 668         begin + FH->pos) ERRNOR (EIO, -1);
 669
 670     count = MIN(count, FH->ino->st.st_size - FH->pos);
 671
 672     if ((count = mc_read (fd, buffer, count)) == -1) ERRNOR (errno, -1);
 673
 674     FH->pos += count;
 675     return count;
 676 }
 677
 678 static int cpio_fh_open(struct vfs_class *me, struct vfs_s_fh *fh, int flags, int mode)
 679 {
 680     (void) fh;
 681     (void) mode;
 682
 683     if ((flags & O_ACCMODE) != O_RDONLY) ERRNOR (EROFS, -1);
 684     return 0;
 685 }
 686
 687 void
 688 init_cpiofs (void)
 689 {
 690     static struct vfs_s_subclass cpio_subclass;
 691
 692     cpio_subclass.flags = VFS_S_READONLY;
 693     cpio_subclass.archive_check = cpio_super_check;
 694     cpio_subclass.archive_same = cpio_super_same;
 695     cpio_subclass.open_archive = cpio_open_archive;
 696     cpio_subclass.free_archive = cpio_free_archive;
 697     cpio_subclass.fh_open = cpio_fh_open;
 698
 699     vfs_s_init_class (&vfs_cpiofs_ops, &cpio_subclass);
 700     vfs_cpiofs_ops.name = "cpiofs";
 701     vfs_cpiofs_ops.prefix = "ucpio";
 702     vfs_cpiofs_ops.read = cpio_read;
 703     vfs_cpiofs_ops.setctl = NULL;
 704     vfs_register_class (&vfs_cpiofs_ops);
 705 }