vfs/extfs.c

   1 /* Virtual File System: External file system.
   2    Copyright (C) 1995, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
   3    2006, 2007, 2009 Free Software Foundation, Inc.
   4
   5    Written by: 1995 Jakub Jelinek
   6    Rewritten by: 1998 Pavel Machek
   7    Additional changes by: 1999 Andrew T. Veliath
   8
   9    This program is free software; you can redistribute it and/or
  10    modify it under the terms of the GNU Library General Public License
  11    as published by the Free Software Foundation; either version 2 of
  12    the License, or (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU Library General Public License for more details.
  18
  19    You should have received a copy of the GNU Library General Public
  20    License along with this program; if not, write to the Free Software
  21    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  22
  23 /**
  24  * \file
  25  * \brief Source: Virtual File System: External file system
  26  * \author Jakub Jelinek
  27  * \author Pavel Machek
  28  * \author Andrew T. Veliath
  29  * \date 1995, 1998, 1999
  30  */
  31
  32 /* Namespace: init_extfs */
  33
  34 #include <config.h>
  35
  36 #include <stdio.h>
  37 #include <ctype.h>
  38 #include <string.h>
  39 #include <stdlib.h>
  40 #include <sys/types.h>
  41 #include <sys/stat.h>
  42 #include <unistd.h>
  43 #include <signal.h>
  44 #include <fcntl.h>
  45 #include <errno.h>
  46 #include <sys/wait.h>
  47
  48 #include "../src/global.h"
  49
  50 #include "../src/wtools.h"      /* message() */
  51 #include "../src/main.h"        /* print_vfs_message */
  52 #include "../src/execute.h"     /* For shell_execute */
  53
  54 #include "utilvfs.h"
  55 #include "vfs.h"
  56 #include "vfs-impl.h"
  57 #include "gc.h"                 /* vfs_rmstamp */
  58
  59 #undef ERRNOR
  60 #define ERRNOR(x,y) do { my_errno = x; return y; } while(0)
  61
  62 struct inode {
  63     nlink_t nlink;
  64     struct entry *first_in_subdir; /* only used if this is a directory */
  65     struct entry *last_in_subdir;
  66     ino_t inode;        /* This is inode # */
  67     dev_t dev;          /* This is an internal identification of the extfs archive */
  68     struct archive *archive; /* And this is an archive structure */
  69     dev_t rdev;
  70     mode_t mode;
  71     uid_t uid;
  72     gid_t gid;
  73     off_t size;
  74     time_t mtime;
  75     char *linkname;
  76     time_t atime;
  77     time_t ctime;
  78     char *local_filename;
  79 };
  80
  81 struct entry {
  82     struct entry *next_in_dir;
  83     struct entry *dir;
  84     char *name;
  85     struct inode *inode;
  86 };
  87
  88 struct pseudofile {
  89     struct archive *archive;
  90     unsigned int has_changed:1;
  91     int local_handle;
  92     struct entry *entry;
  93 };
  94
  95 struct archive {
  96     int fstype;
  97     char *name;
  98     char *local_name;
  99     struct stat local_stat;
 100     dev_t rdev;
 101     int fd_usage;
 102     ino_t inode_counter;
 103     struct entry *root_entry;
 104     struct archive *next;
 105 };
 106
 107 static struct entry *extfs_find_entry (struct entry *dir, char *name,
 108                                        int make_dirs, int make_file);
 109 static int extfs_which (struct vfs_class *me, const char *path);
 110 static void extfs_remove_entry (struct entry *e);
 111 static void extfs_free (vfsid id);
 112 static void extfs_free_entry (struct entry *e);
 113
 114 static struct vfs_class vfs_extfs_ops;
 115 static struct archive *first_archive = NULL;
 116 static int my_errno = 0;
 117
 118 #define MAXEXTFS 32
 119 static char *extfs_prefixes [MAXEXTFS];
 120 static char extfs_need_archive [MAXEXTFS];
 121 static int extfs_no = 0;
 122
 123 static void
 124 extfs_fill_names (struct vfs_class *me, fill_names_f func)
 125 {
 126     struct archive *a = first_archive;
 127     char *name;
 128
 129     (void) me;
 130
 131     while (a) {
 132         name =
 133             g_strconcat (a->name ? a->name : "", "#",
 134                          extfs_prefixes[a->fstype], (char *) NULL);
 135         (*func) (name);
 136         g_free (name);
 137         a = a->next;
 138     }
 139 }
 140
 141 static void extfs_make_dots (struct entry *ent)
 142 {
 143     struct entry *entry = g_new (struct entry, 1);
 144     struct entry *parentry = ent->dir;
 145     struct inode *inode = ent->inode, *parent;
 146
 147     parent = (parentry != NULL) ? parentry->inode : NULL;
 148     entry->name = g_strdup (".");
 149     entry->inode = inode;
 150     entry->dir = ent;
 151     inode->local_filename = NULL;
 152     inode->first_in_subdir = entry;
 153     inode->nlink++;
 154     entry->next_in_dir = g_new (struct entry, 1);
 155     entry = entry->next_in_dir;
 156     entry->name = g_strdup ("..");
 157     inode->last_in_subdir = entry;
 158     entry->next_in_dir = NULL;
 159     if (parent != NULL) {
 160         entry->inode = parent;
 161         entry->dir = parentry;
 162         parent->nlink++;
 163     } else {
 164         entry->inode = inode;
 165         entry->dir = ent;
 166         inode->nlink++;
 167     }
 168 }
 169
 170 static struct entry *extfs_generate_entry (struct archive *archive,
 171     const char *name, struct entry *parentry, mode_t mode)
 172 {
 173     mode_t myumask;
 174     struct inode *inode, *parent;
 175     struct entry *entry;
 176
 177     parent = (parentry != NULL) ? parentry->inode : NULL;
 178     entry = g_new (struct entry, 1);
 179
 180     entry->name = g_strdup (name);
 181     entry->next_in_dir = NULL;
 182     entry->dir = parentry;
 183     if (parent != NULL) {
 184         parent->last_in_subdir->next_in_dir = entry;
 185         parent->last_in_subdir = entry;
 186     }
 187     inode = g_new (struct inode, 1);
 188     entry->inode = inode;
 189     inode->local_filename = NULL;
 190     inode->linkname = NULL;
 191     inode->last_in_subdir = NULL;
 192     inode->inode = (archive->inode_counter)++;
 193     inode->dev = archive->rdev;
 194     inode->archive = archive;
 195     myumask = umask (022);
 196     umask (myumask);
 197     inode->mode = mode & ~myumask;
 198     mode = inode->mode;
 199     inode->rdev = 0;
 200     inode->uid = getuid ();
 201     inode->gid = getgid ();
 202     inode->size = 0;
 203     inode->mtime = time (NULL);
 204     inode->atime = inode->mtime;
 205     inode->ctime = inode->mtime;
 206     inode->nlink = 1;
 207     if (S_ISDIR (mode))
 208         extfs_make_dots (entry);
 209     return entry;
 210 }
 211
 212 #if 0
 213 static void extfs_free_entries (struct entry *entry)
 214 {
 215     (void) entry;
 216     return;
 217 }
 218 #endif
 219
 220 static void extfs_free_archive (struct archive *archive)
 221 {
 222     extfs_free_entry (archive->root_entry);
 223     if (archive->local_name != NULL) {
 224         struct stat my;
 225
 226         mc_stat (archive->local_name, &my);
 227         mc_ungetlocalcopy (archive->name, archive->local_name,
 228             archive->local_stat.st_mtime != my.st_mtime);
 229         g_free(archive->local_name);
 230     }
 231     g_free (archive->name);
 232     g_free (archive);
 233 }
 234
 235 static FILE *
 236 extfs_open_archive (int fstype, const char *name, struct archive **pparc)
 237 {
 238     static dev_t archive_counter = 0;
 239     FILE *result;
 240     mode_t mode;
 241     char *cmd;
 242     char *mc_extfsdir;
 243     struct stat mystat;
 244     struct archive *current_archive;
 245     struct entry *root_entry;
 246     char *local_name = NULL, *tmp = 0;
 247     int uses_archive = extfs_need_archive[fstype];
 248
 249     if (uses_archive) {
 250         if (mc_stat (name, &mystat) == -1)
 251             return NULL;
 252         if (!vfs_file_is_local (name)) {
 253             local_name = mc_getlocalcopy (name);
 254             if (local_name == NULL)
 255                 return NULL;
 256         }
 257         tmp = name_quote (name, 0);
 258     }
 259
 260     mc_extfsdir = concat_dir_and_file (mc_home_alt, "extfs" PATH_SEP_STR);
 261     cmd =
 262         g_strconcat (mc_extfsdir, extfs_prefixes[fstype], " list ",
 263                      local_name ? local_name : tmp, (char *) NULL);
 264     g_free (tmp);
 265     g_free (mc_extfsdir);
 266     open_error_pipe ();
 267     result = popen (cmd, "r");
 268     g_free (cmd);
 269     if (result == NULL) {
 270         close_error_pipe (D_ERROR, NULL);
 271         if (local_name) {
 272             mc_ungetlocalcopy (name, local_name, 0);
 273             g_free(local_name);
 274         }
 275         return NULL;
 276     }
 277 #ifdef ___QNXNTO__
 278     setvbuf (result, NULL, _IONBF, 0);
 279 #endif
 280
 281     current_archive = g_new (struct archive, 1);
 282     current_archive->fstype = fstype;
 283     current_archive->name = name ? g_strdup (name) : NULL;
 284     current_archive->local_name = local_name;
 285
 286     if (local_name != NULL)
 287         mc_stat (local_name, &current_archive->local_stat);
 288     current_archive->inode_counter = 0;
 289     current_archive->fd_usage = 0;
 290     current_archive->rdev = archive_counter++;
 291     current_archive->next = first_archive;
 292     first_archive = current_archive;
 293     mode = mystat.st_mode & 07777;
 294     if (mode & 0400)
 295         mode |= 0100;
 296     if (mode & 0040)
 297         mode |= 0010;
 298     if (mode & 0004)
 299         mode |= 0001;
 300     mode |= S_IFDIR;
 301     root_entry = extfs_generate_entry (current_archive, "/", NULL, mode);
 302     root_entry->inode->uid = mystat.st_uid;
 303     root_entry->inode->gid = mystat.st_gid;
 304     root_entry->inode->atime = mystat.st_atime;
 305     root_entry->inode->ctime = mystat.st_ctime;
 306     root_entry->inode->mtime = mystat.st_mtime;
 307     current_archive->root_entry = root_entry;
 308
 309     *pparc = current_archive;
 310
 311     return result;
 312 }
 313
 314 /*
 315  * Main loop for reading an archive.
 316  * Return 0 on success, -1 on error.
 317  */
 318 static int
 319 extfs_read_archive (int fstype, const char *name, struct archive **pparc)
 320 {
 321     FILE *extfsd;
 322     char *buffer;
 323     struct archive *current_archive;
 324     char *current_file_name, *current_link_name;
 325
 326     if ((extfsd =
 327          extfs_open_archive (fstype, name, &current_archive)) == NULL) {
 328         message (D_ERROR, MSG_ERROR, _("Cannot open %s archive\n%s"),
 329                  extfs_prefixes[fstype], name);
 330         return -1;
 331     }
 332
 333     buffer = g_malloc (4096);
 334     while (fgets (buffer, 4096, extfsd) != NULL) {
 335         struct stat hstat;
 336
 337         current_link_name = NULL;
 338         if (vfs_parse_ls_lga
 339             (buffer, &hstat, &current_file_name, &current_link_name)) {
 340             struct entry *entry, *pent;
 341             struct inode *inode;
 342             char *p, *q, *cfn = current_file_name;
 343
 344             if (*cfn) {
 345                 if (*cfn == '/')
 346                     cfn++;
 347                 p = strchr (cfn, 0);
 348                 if (p != cfn && *(p - 1) == '/')
 349                     *(p - 1) = 0;
 350                 p = strrchr (cfn, '/');
 351                 if (p == NULL) {
 352                     p = cfn;
 353                     q = strchr (cfn, 0);
 354                 } else {
 355                     *(p++) = 0;
 356                     q = cfn;
 357                 }
 358                 if (S_ISDIR (hstat.st_mode)
 359                     && (!strcmp (p, ".") || !strcmp (p, "..")))
 360                     goto read_extfs_continue;
 361                 pent =
 362                     extfs_find_entry (current_archive->root_entry, q, 1,
 363                                       0);
 364                 if (pent == NULL) {
 365                     /* FIXME: Should clean everything one day */
 366                     g_free (buffer);
 367                     pclose (extfsd);
 368                     close_error_pipe (D_ERROR, _("Inconsistent extfs archive"));
 369                     return -1;
 370                 }
 371                 entry = g_new (struct entry, 1);
 372                 entry->name = g_strdup (p);
 373                 entry->next_in_dir = NULL;
 374                 entry->dir = pent;
 375                 if (pent->inode->last_in_subdir) {
 376                     pent->inode->last_in_subdir->next_in_dir = entry;
 377                     pent->inode->last_in_subdir = entry;
 378                 }
 379                 if (!S_ISLNK (hstat.st_mode) && current_link_name != NULL) {
 380                     pent =
 381                         extfs_find_entry (current_archive->root_entry,
 382                                           current_link_name, 0, 0);
 383                     if (pent == NULL) {
 384                         /* FIXME: Should clean everything one day */
 385                         g_free (buffer);
 386                         pclose (extfsd);
 387                         close_error_pipe (D_ERROR,
 388                                           _("Inconsistent extfs archive"));
 389                         return -1;
 390                     } else {
 391                         entry->inode = pent->inode;
 392                         pent->inode->nlink++;
 393                     }
 394                 } else {
 395                     inode = g_new (struct inode, 1);
 396                     entry->inode = inode;
 397                     inode->local_filename = NULL;
 398                     inode->inode = (current_archive->inode_counter)++;
 399                     inode->nlink = 1;
 400                     inode->dev = current_archive->rdev;
 401                     inode->archive = current_archive;
 402                     inode->mode = hstat.st_mode;
 403 #ifdef HAVE_STRUCT_STAT_ST_RDEV
 404                     inode->rdev = hstat.st_rdev;
 405 #else
 406                     inode->rdev = 0;
 407 #endif
 408                     inode->uid = hstat.st_uid;
 409                     inode->gid = hstat.st_gid;
 410                     inode->size = hstat.st_size;
 411                     inode->mtime = hstat.st_mtime;
 412                     inode->atime = hstat.st_atime;
 413                     inode->ctime = hstat.st_ctime;
 414                     inode->first_in_subdir = NULL;
 415                     inode->last_in_subdir = NULL;
 416                     if (current_link_name != NULL
 417                         && S_ISLNK (hstat.st_mode)) {
 418                         inode->linkname = current_link_name;
 419                         current_link_name = NULL;
 420                     } else {
 421                         if (S_ISLNK (hstat.st_mode))
 422                             inode->mode &= ~S_IFLNK;    /* You *DON'T* want to do this always */
 423                         inode->linkname = NULL;
 424                     }
 425                     if (S_ISDIR (hstat.st_mode))
 426                         extfs_make_dots (entry);
 427                 }
 428             }
 429           read_extfs_continue:
 430             g_free (current_file_name);
 431             g_free (current_link_name);
 432         }
 433     }
 434     g_free (buffer);
 435
 436     /* Check if extfs 'list' returned 0 */
 437     if (pclose (extfsd) != 0) {
 438         extfs_free (current_archive);
 439         close_error_pipe (D_ERROR, _("Inconsistent extfs archive"));
 440         return -1;
 441     }
 442
 443     close_error_pipe (D_ERROR, NULL);
 444     *pparc = current_archive;
 445     return 0;
 446 }
 447
 448 /*
 449  * Dissect the path and create corresponding superblock.  Note that inname
 450  * can be changed and the result may point inside the original string.
 451  */
 452 static char *
 453 extfs_get_path_mangle (struct vfs_class *me, char *inname, struct archive **archive,
 454                        int do_not_open)
 455 {
 456     char *local, *op;
 457     const char *archive_name;
 458     int result = -1;
 459     struct archive *parc;
 460     int fstype;
 461
 462     archive_name = inname;
 463     vfs_split (inname, &local, &op);
 464
 465     fstype = extfs_which (me, op);
 466
 467     if (fstype == -1)
 468         return NULL;
 469     if (!local)
 470         local = inname + strlen (inname);
 471
 472     /*
 473      * All filesystems should have some local archive, at least
 474      * it can be '/'.
 475      */
 476     for (parc = first_archive; parc != NULL; parc = parc->next)
 477         if (parc->name) {
 478             if (!strcmp (parc->name, archive_name)) {
 479                 vfs_stamp (&vfs_extfs_ops, (vfsid) parc);
 480                 goto return_success;
 481             }
 482         }
 483
 484     result =
 485         do_not_open ? -1 : extfs_read_archive (fstype, archive_name,
 486                                                &parc);
 487     if (result == -1)
 488         ERRNOR (EIO, NULL);
 489
 490   return_success:
 491     *archive = parc;
 492     return local;
 493 }
 494
 495
 496 /*
 497  * Dissect the path and create corresponding superblock.
 498  * The result should be freed.
 499  */
 500 static char *
 501 extfs_get_path (struct vfs_class *me, const char *inname, struct archive **archive,
 502                 int do_not_open)
 503 {
 504     char *buf = g_strdup (inname);
 505     char *res = extfs_get_path_mangle (me, buf, archive, do_not_open);
 506     char *res2 = NULL;
 507     if (res)
 508         res2 = g_strdup (res);
 509     g_free (buf);
 510     return res2;
 511 }
 512
 513
 514 /* Return allocated path (without leading slash) inside the archive  */
 515 static char *extfs_get_path_from_entry (struct entry *entry)
 516 {
 517     struct list {
 518         struct list *next;
 519         char *name;
 520     } *head, *p;
 521     char *localpath;
 522     size_t len;
 523
 524     for (len = 0, head = 0; entry->dir; entry = entry->dir) {
 525         p = g_new (struct list, 1);
 526         p->next = head;
 527         p->name = entry->name;
 528         head = p;
 529         len += strlen (entry->name) + 1;
 530     }
 531
 532     if (len == 0)
 533         return g_strdup ("");
 534
 535     localpath = g_malloc (len);
 536     *localpath = '\0';
 537     while (head) {
 538         strcat (localpath, head->name);
 539         if (head->next)
 540             strcat (localpath, "/");
 541         p = head;
 542         head = head->next;
 543         g_free (p);
 544     }
 545     return (localpath);
 546 }
 547
 548
 549 struct loop_protect {
 550     struct entry *entry;
 551     struct loop_protect *next;
 552 };
 553 static int errloop;
 554 static int notadir;
 555
 556 static struct entry *
 557 extfs_find_entry_int (struct entry *dir, char *name,
 558                     struct loop_protect *list, int make_dirs, int make_file);
 559
 560 static struct entry *
 561 extfs_resolve_symlinks_int (struct entry *entry,
 562                           struct loop_protect *list)
 563 {
 564     struct entry *pent;
 565     struct loop_protect *looping;
 566
 567     if (!S_ISLNK (entry->inode->mode))
 568         return entry;
 569     for (looping = list; looping != NULL; looping = looping->next)
 570         if (entry == looping->entry) { /* Here we protect us against symlink looping */
 571             errloop = 1;
 572             return NULL;
 573         }
 574     looping = g_new (struct loop_protect, 1);
 575     looping->entry = entry;
 576     looping->next = list;
 577     pent = extfs_find_entry_int (entry->dir, entry->inode->linkname, looping, 0, 0);
 578     g_free (looping);
 579     if (pent == NULL)
 580         my_errno = ENOENT;
 581     return pent;
 582 }
 583
 584 static struct entry *extfs_resolve_symlinks (struct entry *entry)
 585 {
 586     struct entry *res;
 587
 588     errloop = 0;
 589     notadir = 0;
 590     res = extfs_resolve_symlinks_int (entry, NULL);
 591     if (res == NULL) {
 592         if (errloop)
 593             my_errno = ELOOP;
 594         else if (notadir)
 595             my_errno = ENOTDIR;
 596     }
 597     return res;
 598 }
 599
 600 static const char *
 601 extfs_get_archive_name (struct archive *archive)
 602 {
 603     const char *archive_name;
 604
 605     if (archive->local_name)
 606         archive_name = archive->local_name;
 607     else
 608         archive_name = archive->name;
 609
 610     if (!archive_name || !*archive_name)
 611         return "no_archive_name";
 612     else
 613         return archive_name;
 614 }
 615
 616 /* Don't pass localname as NULL */
 617 static int
 618 extfs_cmd (const char *str_extfs_cmd, struct archive *archive,
 619            struct entry *entry, const char *localname)
 620 {
 621     char *file;
 622     char *quoted_file;
 623     char *quoted_localname;
 624     char *archive_name;
 625     char *mc_extfsdir;
 626     char *cmd;
 627     int retval;
 628
 629     file = extfs_get_path_from_entry (entry);
 630     quoted_file = name_quote (file, 0);
 631     g_free (file);
 632     archive_name = name_quote (extfs_get_archive_name (archive), 0);
 633     quoted_localname = name_quote (localname, 0);
 634
 635     mc_extfsdir = concat_dir_and_file (mc_home_alt, "extfs" PATH_SEP_STR);
 636     cmd = g_strconcat (mc_extfsdir, extfs_prefixes[archive->fstype],
 637                        str_extfs_cmd, archive_name, " ", quoted_file, " ",
 638                        quoted_localname, (char *) NULL);
 639     g_free (quoted_file);
 640     g_free (quoted_localname);
 641     g_free (mc_extfsdir);
 642     g_free (archive_name);
 643
 644     open_error_pipe ();
 645     retval = my_system (EXECUTE_AS_SHELL, shell, cmd);
 646     g_free (cmd);
 647     close_error_pipe (D_ERROR, NULL);
 648     return retval;
 649 }
 650
 651 static void
 652 extfs_run (struct vfs_class *me, const char *file)
 653 {
 654     struct archive *archive = NULL;
 655     char *p, *q, *archive_name, *mc_extfsdir;
 656     char *cmd;
 657
 658     if ((p = extfs_get_path (me, file, &archive, 0)) == NULL)
 659         return;
 660     q = name_quote (p, 0);
 661     g_free (p);
 662
 663     archive_name = name_quote (extfs_get_archive_name (archive), 0);
 664     mc_extfsdir = concat_dir_and_file (mc_home_alt, "extfs" PATH_SEP_STR);
 665     cmd = g_strconcat (mc_extfsdir, extfs_prefixes[archive->fstype],
 666                        " run ", archive_name, " ", q, (char *) NULL);
 667     g_free (mc_extfsdir);
 668     g_free (archive_name);
 669     g_free (q);
 670     shell_execute (cmd, 0);
 671     g_free (cmd);
 672 }
 673
 674 static void *
 675 extfs_open (struct vfs_class *me, const char *file, int flags, int mode)
 676 {
 677     struct pseudofile *extfs_info;
 678     struct archive *archive = NULL;
 679     char *q;
 680     struct entry *entry;
 681     int local_handle;
 682     int created = 0;
 683
 684     if ((q = extfs_get_path (me, file, &archive, 0)) == NULL)
 685         return NULL;
 686     entry = extfs_find_entry (archive->root_entry, q, 0, 0);
 687     if (entry == NULL && (flags & O_CREAT)) {
 688         /* Create new entry */
 689         entry = extfs_find_entry (archive->root_entry, q, 0, 1);
 690         created = (entry != NULL);
 691     }
 692
 693     g_free (q);
 694     if (entry == NULL)
 695         return NULL;
 696     if ((entry = extfs_resolve_symlinks (entry)) == NULL)
 697         return NULL;
 698
 699     if (S_ISDIR (entry->inode->mode))
 700         ERRNOR (EISDIR, NULL);
 701
 702     if (entry->inode->local_filename == NULL) {
 703         char *local_filename;
 704
 705         local_handle = vfs_mkstemps (&local_filename, "extfs", entry->name);
 706
 707         if (local_handle == -1)
 708             return NULL;
 709         close (local_handle);
 710
 711         if (!created && !(flags & O_TRUNC)
 712             && extfs_cmd (" copyout ", archive, entry, local_filename)) {
 713             unlink (local_filename);
 714             g_free (local_filename);
 715             my_errno = EIO;
 716             return NULL;
 717         }
 718         entry->inode->local_filename = local_filename;
 719     }
 720
 721     local_handle =
 722         open (entry->inode->local_filename, NO_LINEAR (flags), mode);
 723
 724     if (local_handle == -1) {
 725         /* file exists(may be). Need to drop O_CREAT flag and truncate file content */
 726         flags = ~O_CREAT & (NO_LINEAR (flags)|O_TRUNC);
 727         local_handle = open (entry->inode->local_filename, flags  , mode);
 728     }
 729
 730     if (local_handle == -1)
 731         ERRNOR (EIO, NULL);
 732
 733     extfs_info = g_new (struct pseudofile, 1);
 734     extfs_info->archive = archive;
 735     extfs_info->entry = entry;
 736     extfs_info->has_changed = created;
 737     extfs_info->local_handle = local_handle;
 738
 739     /* i.e. we had no open files and now we have one */
 740     vfs_rmstamp (&vfs_extfs_ops, (vfsid) archive);
 741     archive->fd_usage++;
 742     return extfs_info;
 743 }
 744
 745 static ssize_t extfs_read (void *data, char *buffer, int count)
 746 {
 747     struct pseudofile *file = (struct pseudofile *)data;
 748
 749     return read (file->local_handle, buffer, count);
 750 }
 751
 752 static int
 753 extfs_close (void *data)
 754 {
 755     struct pseudofile *file;
 756     int errno_code = 0;
 757     file = (struct pseudofile *) data;
 758
 759     close (file->local_handle);
 760
 761     /* Commit the file if it has changed */
 762     if (file->has_changed) {
 763         if (extfs_cmd
 764             (" copyin ", file->archive, file->entry,
 765              file->entry->inode->local_filename))
 766             errno_code = EIO;
 767         {
 768             struct stat file_status;
 769             if (stat (file->entry->inode->local_filename, &file_status) !=
 770                 0)
 771                 errno_code = EIO;
 772             else
 773                 file->entry->inode->size = file_status.st_size;
 774         }
 775
 776         file->entry->inode->mtime = time (NULL);
 777     }
 778
 779     file->archive->fd_usage--;
 780     if (!file->archive->fd_usage)
 781         vfs_stamp_create (&vfs_extfs_ops, file->archive);
 782
 783     g_free (data);
 784     if (errno_code)
 785         ERRNOR (EIO, -1);
 786     return 0;
 787 }
 788
 789 #define RECORDSIZE 512
 790
 791 static struct entry*
 792 extfs_find_entry_int (struct entry *dir, char *name,
 793                      struct loop_protect *list, int make_dirs, int make_file)
 794 {
 795     struct entry *pent, *pdir;
 796     char *p, *q, *name_end;
 797     char c;
 798
 799     if (*name == '/') { /* Handle absolute paths */
 800         name++;
 801         dir = dir->inode->archive->root_entry;
 802     }
 803
 804     pent = dir;
 805     p = name;
 806     name_end = name + strlen (name);
 807     q = strchr (p, '/');
 808     c = '/';
 809     if (!q)
 810         q = strchr (p, 0);
 811
 812     for (; pent != NULL && c && *p; ){
 813         c = *q;
 814         *q = 0;
 815
 816         if (strcmp (p, ".")){
 817             if (!strcmp (p, ".."))
 818                 pent = pent->dir;
 819             else {
 820                 if ((pent = extfs_resolve_symlinks_int (pent, list))==NULL){
 821                     *q = c;
 822                     return NULL;
 823                 }
 824                 if (!S_ISDIR (pent->inode->mode)){
 825                     *q = c;
 826                     notadir = 1;
 827                     return NULL;
 828                 }
 829                 pdir = pent;
 830                 for (pent = pent->inode->first_in_subdir; pent; pent = pent->next_in_dir)
 831                     /* Hack: I keep the original semanthic unless
 832                        q+1 would break in the strchr */
 833                     if (!strcmp (pent->name, p)){
 834                         if (q + 1 > name_end){
 835                             *q = c;
 836                             notadir = !S_ISDIR (pent->inode->mode);
 837                             return pent;
 838                         }
 839                         break;
 840                     }
 841
 842                 /* When we load archive, we create automagically
 843                  * non-existant directories
 844                  */
 845                 if (pent == NULL && make_dirs) {
 846                     pent = extfs_generate_entry (dir->inode->archive, p, pdir, S_IFDIR | 0777);
 847                 }
 848                 if (pent == NULL && make_file) {
 849                     pent = extfs_generate_entry (dir->inode->archive, p, pdir, S_IFREG | 0666);
 850                 }
 851             }
 852         }
 853         /* Next iteration */
 854         *q = c;
 855         p = q + 1;
 856         q = strchr (p, '/');
 857         if (!q)
 858             q = strchr (p, 0);
 859     }
 860     if (pent == NULL)
 861         my_errno = ENOENT;
 862     return pent;
 863 }
 864
 865 static struct entry *extfs_find_entry (struct entry *dir, char *name, int make_dirs, int make_file)
 866 {
 867     struct entry *res;
 868
 869     errloop = 0;
 870     notadir = 0;
 871     res = extfs_find_entry_int (dir, name, NULL, make_dirs, make_file);
 872     if (res == NULL) {
 873         if (errloop)
 874             my_errno = ELOOP;
 875         else if (notadir)
 876             my_errno = ENOTDIR;
 877     }
 878     return res;
 879 }
 880
 881
 882 static int extfs_errno (struct vfs_class *me)
 883 {
 884     (void) me;
 885
 886     return my_errno;
 887 }
 888
 889 static void * extfs_opendir (struct vfs_class *me, const char *dirname)
 890 {
 891     struct archive *archive = NULL;
 892     char *q;
 893     struct entry *entry;
 894     struct entry **info;
 895
 896     if ((q = extfs_get_path (me, dirname, &archive, 0)) == NULL)
 897         return NULL;
 898     entry = extfs_find_entry (archive->root_entry, q, 0, 0);
 899     g_free (q);
 900     if (entry == NULL)
 901         return NULL;
 902     if ((entry = extfs_resolve_symlinks (entry)) == NULL)
 903         return NULL;
 904     if (!S_ISDIR (entry->inode->mode)) ERRNOR (ENOTDIR, NULL);
 905
 906     info = g_new (struct entry *, 2);
 907     info[0] = entry->inode->first_in_subdir;
 908     info[1] = entry->inode->first_in_subdir;
 909
 910     return info;
 911 }
 912
 913 static void * extfs_readdir(void *data)
 914 {
 915     static union vfs_dirent dir;
 916     struct entry **info = (struct entry **) data;
 917
 918     if (!*info)
 919         return NULL;
 920
 921     g_strlcpy(dir.dent.d_name, (*info)->name, MC_MAXPATHLEN);
 922
 923     compute_namelen(&dir.dent);
 924     *info = (*info)->next_in_dir;
 925
 926     return (void *) &dir;
 927 }
 928
 929 static int extfs_closedir (void *data)
 930 {
 931     g_free (data);
 932     return 0;
 933 }
 934
 935 static void extfs_stat_move (struct stat *buf, const struct inode *inode)
 936 {
 937     buf->st_dev = inode->dev;
 938     buf->st_ino = inode->inode;
 939     buf->st_mode = inode->mode;
 940     buf->st_nlink = inode->nlink;
 941     buf->st_uid = inode->uid;
 942     buf->st_gid = inode->gid;
 943 #ifdef HAVE_STRUCT_STAT_ST_RDEV
 944     buf->st_rdev = inode->rdev;
 945 #endif
 946     buf->st_size = inode->size;
 947 #ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
 948     buf->st_blksize = RECORDSIZE;
 949 #endif
 950 #ifdef HAVE_STRUCT_STAT_ST_BLOCKS
 951     buf->st_blocks = (inode->size + RECORDSIZE - 1) / RECORDSIZE;
 952 #endif
 953     buf->st_atime = inode->atime;
 954     buf->st_mtime = inode->mtime;
 955     buf->st_ctime = inode->ctime;
 956 }
 957
 958 static int
 959 extfs_internal_stat (struct vfs_class *me, const char *path, struct stat *buf,
 960                      int resolve)
 961 {
 962     struct archive *archive;
 963     char *q;
 964     struct entry *entry;
 965     char *path2 = g_strdup (path);
 966     int result = -1;
 967
 968     if ((q = extfs_get_path_mangle (me, path2, &archive, 0)) == NULL)
 969         goto cleanup;
 970     entry = extfs_find_entry (archive->root_entry, q, 0, 0);
 971     if (entry == NULL)
 972         goto cleanup;
 973     if (resolve && (entry = extfs_resolve_symlinks (entry)) == NULL)
 974         goto cleanup;
 975     extfs_stat_move (buf, entry->inode);
 976     result = 0;
 977 cleanup:
 978     g_free (path2);
 979     return result;
 980 }
 981
 982 static int extfs_stat (struct vfs_class *me, const char *path, struct stat *buf)
 983 {
 984     return extfs_internal_stat (me, path, buf, 1);
 985 }
 986
 987 static int extfs_lstat (struct vfs_class *me, const char *path, struct stat *buf)
 988 {
 989     return extfs_internal_stat (me, path, buf, 0);
 990 }
 991
 992 static int extfs_fstat (void *data, struct stat *buf)
 993 {
 994     struct pseudofile *file = (struct pseudofile *)data;
 995
 996     extfs_stat_move (buf, file->entry->inode);
 997     return 0;
 998 }
 999
1000 static int
1001 extfs_readlink (struct vfs_class *me, const char *path, char *buf, size_t size)
1002 {
1003     struct archive *archive;
1004     char *q;
1005     size_t len;
1006     struct entry *entry;
1007     char *mpath = g_strdup (path);
1008     int result = -1;
1009
1010     if ((q = extfs_get_path_mangle (me, mpath, &archive, 0)) == NULL)
1011         goto cleanup;
1012     entry = extfs_find_entry (archive->root_entry, q, 0, 0);
1013     if (entry == NULL)
1014         goto cleanup;
1015     if (!S_ISLNK (entry->inode->mode)) {
1016         me->verrno = EINVAL;
1017         goto cleanup;
1018     }
1019     len = strlen (entry->inode->linkname);
1020     if (size < len)
1021        len = size;
1022     /* readlink() does not append a NUL character to buf */
1023     memcpy (buf, entry->inode->linkname, result = len);
1024 cleanup:
1025     g_free (mpath);
1026     return result;
1027 }
1028
1029 static int extfs_chown (struct vfs_class *me, const char *path, int owner, int group)
1030 {
1031     (void) me;
1032     (void) path;
1033     (void) owner;
1034     (void) group;
1035     return 0;
1036 }
1037
1038 static int extfs_chmod (struct vfs_class *me, const char *path, int mode)
1039 {
1040     (void) me;
1041     (void) path;
1042     (void) mode;
1043     return 0;
1044 }
1045
1046 static ssize_t extfs_write (void *data, const char *buf, int nbyte)
1047 {
1048     struct pseudofile *file = (struct pseudofile *)data;
1049
1050     file->has_changed = 1;
1051     return write (file->local_handle, buf, nbyte);
1052 }
1053
1054 static int extfs_unlink (struct vfs_class *me, const char *file)
1055 {
1056     struct archive *archive;
1057     char *q, *mpath = g_strdup (file);
1058     struct entry *entry;
1059     int result = -1;
1060
1061     if ((q = extfs_get_path_mangle (me, mpath, &archive, 0)) == NULL)
1062         goto cleanup;
1063     entry = extfs_find_entry (archive->root_entry, q, 0, 0);
1064     if (entry == NULL)
1065         goto cleanup;
1066     if ((entry = extfs_resolve_symlinks (entry)) == NULL)
1067         goto cleanup;
1068     if (S_ISDIR (entry->inode->mode)) {
1069         me->verrno = EISDIR;
1070         goto cleanup;
1071     }
1072     if (extfs_cmd (" rm ", archive, entry, "")){
1073         my_errno = EIO;
1074         goto cleanup;
1075     }
1076     extfs_remove_entry (entry);
1077     result = 0;
1078 cleanup:
1079     g_free (mpath);
1080     return result;
1081 }
1082
1083 static int extfs_mkdir (struct vfs_class *me, const char *path, mode_t mode)
1084 {
1085     struct archive *archive;
1086     char *q, *mpath = g_strdup(path);
1087     struct entry *entry;
1088     int result = -1;
1089
1090     (void) mode;
1091
1092     if ((q = extfs_get_path_mangle (me, mpath, &archive, 0)) == NULL)
1093         goto cleanup;
1094     entry = extfs_find_entry (archive->root_entry, q, 0, 0);
1095     if (entry != NULL) {
1096         me->verrno = EEXIST;
1097         goto cleanup;
1098     }
1099     entry = extfs_find_entry (archive->root_entry, q, 1, 0);
1100     if (entry == NULL)
1101         goto cleanup;
1102     if ((entry = extfs_resolve_symlinks (entry)) == NULL)
1103         goto cleanup;
1104     if (!S_ISDIR (entry->inode->mode)) {
1105         me->verrno = ENOTDIR;
1106         goto cleanup;
1107     }
1108
1109     if (extfs_cmd (" mkdir ", archive, entry, "")){
1110         my_errno = EIO;
1111         extfs_remove_entry (entry);
1112         goto cleanup;
1113     }
1114     result = 0;
1115 cleanup:
1116     g_free (mpath);
1117     return result;
1118 }
1119
1120 static int extfs_rmdir (struct vfs_class *me, const char *path)
1121 {
1122     struct archive *archive;
1123     char *q, *mpath = g_strdup(path);
1124     struct entry *entry;
1125     int result = -1;
1126
1127     if ((q = extfs_get_path_mangle (me, mpath, &archive, 0)) == NULL)
1128         goto cleanup;
1129     entry = extfs_find_entry (archive->root_entry, q, 0, 0);
1130     if (entry == NULL)
1131         goto cleanup;
1132     if ((entry = extfs_resolve_symlinks (entry)) == NULL)
1133         goto cleanup;
1134     if (!S_ISDIR (entry->inode->mode)) {
1135         me->verrno = ENOTDIR;
1136         goto cleanup;
1137     }
1138
1139     if (extfs_cmd (" rmdir ", archive, entry, "")){
1140         my_errno = EIO;
1141         goto cleanup;
1142     }
1143     extfs_remove_entry (entry);
1144     result = 0;
1145 cleanup:
1146     g_free (mpath);
1147     return result;
1148 }
1149
1150 static int
1151 extfs_chdir (struct vfs_class *me, const char *path)
1152 {
1153     struct archive *archive = NULL;
1154     char *q;
1155     struct entry *entry;
1156
1157     my_errno = ENOTDIR;
1158     if ((q = extfs_get_path (me, path, &archive, 0)) == NULL)
1159         return -1;
1160     entry = extfs_find_entry (archive->root_entry, q, 0, 0);
1161     g_free (q);
1162     if (!entry)
1163         return -1;
1164     entry = extfs_resolve_symlinks (entry);
1165     if ((!entry) || (!S_ISDIR (entry->inode->mode)))
1166         return -1;
1167     my_errno = 0;
1168     return 0;
1169 }
1170
1171 static off_t extfs_lseek (void *data, off_t offset, int whence)
1172 {
1173     struct pseudofile *file = (struct pseudofile *) data;
1174
1175     return lseek (file->local_handle, offset, whence);
1176 }
1177
1178 static vfsid
1179 extfs_getid (struct vfs_class *me, const char *path)
1180 {
1181     struct archive *archive = NULL;
1182     char *p;
1183
1184     if (!(p = extfs_get_path (me, path, &archive, 1)))
1185         return NULL;
1186     g_free (p);
1187     return (vfsid) archive;
1188 }
1189
1190 static int extfs_nothingisopen (vfsid id)
1191 {
1192     if (((struct archive *)id)->fd_usage <= 0)
1193         return 1;
1194     return 0;
1195 }
1196
1197 static void extfs_remove_entry (struct entry *e)
1198 {
1199     int i = --(e->inode->nlink);
1200     struct entry *pe, *ent, *prev;
1201
1202     if (S_ISDIR (e->inode->mode) && e->inode->first_in_subdir != NULL) {
1203         struct entry *f = e->inode->first_in_subdir;
1204         e->inode->first_in_subdir = NULL;
1205         extfs_remove_entry (f);
1206     }
1207     pe = e->dir;
1208     if (e == pe->inode->first_in_subdir)
1209         pe->inode->first_in_subdir = e->next_in_dir;
1210
1211     prev = NULL;
1212     for (ent = pe->inode->first_in_subdir; ent && ent->next_in_dir;
1213          ent = ent->next_in_dir)
1214             if (e == ent->next_in_dir) {
1215                 prev = ent;
1216                 break;
1217             }
1218     if (prev)
1219         prev->next_in_dir = e->next_in_dir;
1220     if (e == pe->inode->last_in_subdir)
1221         pe->inode->last_in_subdir = prev;
1222
1223     if (i <= 0) {
1224         if (e->inode->local_filename != NULL) {
1225             unlink (e->inode->local_filename);
1226             g_free (e->inode->local_filename);
1227         }
1228         g_free (e->inode->linkname);
1229         g_free (e->inode);
1230     }
1231
1232     g_free (e->name);
1233     g_free (e);
1234 }
1235
1236 static void extfs_free_entry (struct entry *e)
1237 {
1238     int i = --(e->inode->nlink);
1239     if (S_ISDIR (e->inode->mode) && e->inode->first_in_subdir != NULL) {
1240         struct entry *f = e->inode->first_in_subdir;
1241
1242         e->inode->first_in_subdir = NULL;
1243         extfs_free_entry (f);
1244     }
1245     if (i <= 0) {
1246         if (e->inode->local_filename != NULL) {
1247             unlink (e->inode->local_filename);
1248             g_free (e->inode->local_filename);
1249         }
1250         g_free (e->inode->linkname);
1251         g_free (e->inode);
1252     }
1253     if (e->next_in_dir != NULL)
1254         extfs_free_entry (e->next_in_dir);
1255     g_free (e->name);
1256     g_free (e);
1257 }
1258
1259 static void extfs_free (vfsid id)
1260 {
1261     struct archive *parc;
1262     struct archive *archive = (struct archive *)id;
1263
1264     if (archive == first_archive) {
1265         first_archive = archive->next;
1266     } else {
1267         for (parc = first_archive; parc != NULL; parc = parc->next)
1268             if (parc->next == archive) {
1269                 parc->next = archive->next;
1270                 break;
1271             }
1272     }
1273     extfs_free_archive (archive);
1274 }
1275
1276 static char *
1277 extfs_getlocalcopy (struct vfs_class *me, const char *path)
1278 {
1279     struct pseudofile *fp =
1280         (struct pseudofile *) extfs_open (me, path, O_RDONLY, 0);
1281     char *p;
1282
1283     if (fp == NULL)
1284         return NULL;
1285     if (fp->entry->inode->local_filename == NULL) {
1286         extfs_close ((void *) fp);
1287         return NULL;
1288     }
1289     p = g_strdup (fp->entry->inode->local_filename);
1290     fp->archive->fd_usage++;
1291     extfs_close ((void *) fp);
1292     return p;
1293 }
1294
1295 static int
1296 extfs_ungetlocalcopy (struct vfs_class *me, const char *path,
1297                       const char *local, int has_changed)
1298 {
1299     struct pseudofile *fp =
1300         (struct pseudofile *) extfs_open (me, path, O_RDONLY, 0);
1301
1302     if (fp == NULL)
1303         return 0;
1304     if (!strcmp (fp->entry->inode->local_filename, local)) {
1305         fp->archive->fd_usage--;
1306         fp->has_changed |= has_changed;
1307         extfs_close ((void *) fp);
1308         return 0;
1309     } else {
1310         /* Should not happen */
1311         extfs_close ((void *) fp);
1312         return 0;
1313     }
1314 }
1315
1316
1317 static int extfs_init (struct vfs_class *me)
1318 {
1319     FILE *cfg;
1320     char *mc_extfsini;
1321     char key[256];
1322
1323     (void) me;
1324
1325     mc_extfsini = concat_dir_and_file (mc_home, "extfs" PATH_SEP_STR "extfs.ini");
1326     cfg = fopen (mc_extfsini, "r");
1327
1328     /* We may not use vfs_die() message or message or similar,
1329      * UI is not initialized at this time and message would not
1330      * appear on screen. */
1331     if (!cfg) {
1332         fprintf (stderr, _("Warning: file %s not found\n"), mc_extfsini);
1333         g_free (mc_extfsini);
1334         return 0;
1335     }
1336
1337     extfs_no = 0;
1338     while (extfs_no < MAXEXTFS && fgets (key, sizeof (key), cfg)) {
1339         char *c;
1340
1341         /* Handle those with a trailing ':', those flag that the
1342          * file system does not require an archive to work
1343          */
1344
1345         if (*key == '[') {
1346             fprintf(stderr, "Warning: You need to update your %s file.\n",
1347                     mc_extfsini);
1348             fclose(cfg);
1349             g_free (mc_extfsini);
1350             return 0;
1351         }
1352         if (*key == '#' || *key == '\n')
1353             continue;
1354
1355         if ((c = strchr (key, '\n'))){
1356             *c-- = 0;
1357         } else {        /* Last line without newline or strlen (key) > 255 */
1358             c = &key [strlen (key) - 1];
1359         }
1360         extfs_need_archive [extfs_no] = !(*c == ':');
1361         if (*c == ':')
1362             *c = 0;
1363         if (!(*key))
1364             continue;
1365
1366         extfs_prefixes [extfs_no++] = g_strdup (key);
1367     }
1368     fclose(cfg);
1369     g_free (mc_extfsini);
1370     return 1;
1371 }
1372
1373 static int extfs_which (struct vfs_class *me, const char *path)
1374 {
1375     int i;
1376
1377     (void) me;
1378
1379     for (i = 0; i < extfs_no; i++)
1380         if (!strcmp (path, extfs_prefixes [i]))
1381             return i;
1382     return -1;
1383 }
1384
1385 static void extfs_done (struct vfs_class *me)
1386 {
1387     int i;
1388     struct archive *ar;
1389
1390     (void) me;
1391
1392     for (ar = first_archive; ar != NULL;) {
1393         extfs_free ((vfsid) ar);
1394         ar = first_archive;
1395     }
1396
1397     for (i = 0; i < extfs_no; i++ )
1398         g_free (extfs_prefixes [i]);
1399     extfs_no = 0;
1400 }
1401
1402 static int
1403 extfs_setctl (struct vfs_class *me, const char *path, int ctlop, void *arg)
1404 {
1405     (void) arg;
1406
1407     if (ctlop == VFS_SETCTL_RUN) {
1408         extfs_run (me, path);
1409         return 1;
1410     }
1411     return 0;
1412 }
1413
1414 void
1415 init_extfs (void)
1416 {
1417     vfs_extfs_ops.name = "extfs";
1418     vfs_extfs_ops.init = extfs_init;
1419     vfs_extfs_ops.done = extfs_done;
1420     vfs_extfs_ops.fill_names = extfs_fill_names;
1421     vfs_extfs_ops.which = extfs_which;
1422     vfs_extfs_ops.open = extfs_open;
1423     vfs_extfs_ops.close = extfs_close;
1424     vfs_extfs_ops.read = extfs_read;
1425     vfs_extfs_ops.write = extfs_write;
1426     vfs_extfs_ops.opendir = extfs_opendir;
1427     vfs_extfs_ops.readdir = extfs_readdir;
1428     vfs_extfs_ops.closedir = extfs_closedir;
1429     vfs_extfs_ops.stat = extfs_stat;
1430     vfs_extfs_ops.lstat = extfs_lstat;
1431     vfs_extfs_ops.fstat = extfs_fstat;
1432     vfs_extfs_ops.chmod = extfs_chmod;
1433     vfs_extfs_ops.chown = extfs_chown;
1434     vfs_extfs_ops.readlink = extfs_readlink;
1435     vfs_extfs_ops.unlink = extfs_unlink;
1436     vfs_extfs_ops.chdir = extfs_chdir;
1437     vfs_extfs_ops.ferrno = extfs_errno;
1438     vfs_extfs_ops.lseek = extfs_lseek;
1439     vfs_extfs_ops.getid = extfs_getid;
1440     vfs_extfs_ops.nothingisopen = extfs_nothingisopen;
1441     vfs_extfs_ops.free = extfs_free;
1442     vfs_extfs_ops.getlocalcopy = extfs_getlocalcopy;
1443     vfs_extfs_ops.ungetlocalcopy = extfs_ungetlocalcopy;
1444     vfs_extfs_ops.mkdir = extfs_mkdir;
1445     vfs_extfs_ops.rmdir = extfs_rmdir;
1446     vfs_extfs_ops.setctl = extfs_setctl;
1447     vfs_register_class (&vfs_extfs_ops);
1448 }