Merge branch '4561_tar_segfault'
[midnight-commander.git] / lib / vfs / vfs.c
blobf4dad4649a7948e48baa5bb1f90c3cebd19eb721
1 /*
2 Virtual File System switch code
4 Copyright (C) 1995-2024
5 Free Software Foundation, Inc.
7 Written by: 1995 Miguel de Icaza
8 Jakub Jelinek, 1995
9 Pavel Machek, 1998
10 Slava Zanko <slavazanko@gmail.com>, 2011-2013
11 Andrew Borodin <aborodin@vmail.ru>, 2011-2022
13 This file is part of the Midnight Commander.
15 The Midnight Commander is free software: you can redistribute it
16 and/or modify it under the terms of the GNU General Public License as
17 published by the Free Software Foundation, either version 3 of the License,
18 or (at your option) any later version.
20 The Midnight Commander is distributed in the hope that it will be useful,
21 but WITHOUT ANY WARRANTY; without even the implied warranty of
22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 GNU General Public License for more details.
25 You should have received a copy of the GNU General Public License
26 along with this program. If not, see <http://www.gnu.org/licenses/>.
29 /**
30 * \file
31 * \brief Source: Virtual File System switch code
32 * \author Miguel de Icaza
33 * \author Jakub Jelinek
34 * \author Pavel Machek
35 * \date 1995, 1998
36 * \warning functions like extfs_lstat() have right to destroy any
37 * strings you pass to them. This is actually ok as you g_strdup what
38 * you are passing to them, anyway; still, beware.
40 * Namespace: exports *many* functions with vfs_ prefix; exports
41 * parse_ls_lga and friends which do not have that prefix.
44 #include <config.h>
46 #include <errno.h>
47 #include <stdlib.h>
49 #ifdef __linux__
50 #ifdef HAVE_LINUX_FS_H
51 #include <linux/fs.h>
52 #endif /* HAVE_LINUX_FS_H */
53 #ifdef HAVE_SYS_IOCTL_H
54 #include <sys/ioctl.h>
55 #endif /* HAVE_SYS_IOCTL_H */
56 #endif /* __linux__ */
58 #include "lib/global.h"
59 #include "lib/strutil.h"
60 #include "lib/util.h"
61 #include "lib/widget.h" /* message() */
62 #include "lib/event.h"
64 #ifdef HAVE_CHARSET
65 #include "lib/charsets.h"
66 #endif
68 #include "vfs.h"
69 #include "utilvfs.h"
70 #include "gc.h"
72 /* TODO: move it to the separate .h */
73 extern struct vfs_dirent *mc_readdir_result;
74 extern GPtrArray *vfs__classes_list;
75 extern GString *vfs_str_buffer;
76 extern vfs_class *current_vfs;
78 /*** global variables ****************************************************************************/
80 struct vfs_dirent *mc_readdir_result = NULL;
81 GPtrArray *vfs__classes_list = NULL;
82 GString *vfs_str_buffer = NULL;
83 vfs_class *current_vfs = NULL;
85 /*** file scope macro definitions ****************************************************************/
87 #define VFS_FIRST_HANDLE 100
89 /*** file scope type declarations ****************************************************************/
91 struct vfs_openfile
93 int handle;
94 vfs_class *vclass;
95 void *fsinfo;
98 /*** forward declarations (file scope functions) *************************************************/
100 /*** file scope variables ************************************************************************/
102 /** They keep track of the current directory */
103 static vfs_path_t *current_path = NULL;
105 static GPtrArray *vfs_openfiles = NULL;
106 static long vfs_free_handle_list = -1;
108 /* --------------------------------------------------------------------------------------------- */
109 /*** file scope functions ************************************************************************/
110 /* --------------------------------------------------------------------------------------------- */
111 /* now used only by vfs_translate_path, but could be used in other vfs
112 * plugin to automatic detect encoding
113 * path - path to translate
114 * size - how many bytes from path translate
115 * defcnv - converter, that is used as default, when path does not contain any
116 * #enc: substring
117 * buffer - used to store result of translation
120 static estr_t
121 _vfs_translate_path (const char *path, int size, GIConv defcnv, GString *buffer)
123 estr_t state = ESTR_SUCCESS;
124 #ifdef HAVE_CHARSET
125 const char *semi;
127 if (size == 0)
128 return ESTR_SUCCESS;
130 size = (size > 0) ? size : (signed int) strlen (path);
132 /* try found /#enc: */
133 semi = g_strrstr_len (path, size, VFS_ENCODING_PREFIX);
134 if (semi != NULL && (semi == path || IS_PATH_SEP (semi[-1])))
136 char encoding[16];
137 const char *slash;
138 GIConv coder = INVALID_CONV;
139 int ms;
141 /* first must be translated part before #enc: */
142 ms = semi - path;
144 state = _vfs_translate_path (path, ms, defcnv, buffer);
146 if (state != ESTR_SUCCESS)
147 return state;
149 /* now can be translated part after #enc: */
150 semi += strlen (VFS_ENCODING_PREFIX); /* skip "#enc:" */
151 slash = strchr (semi, PATH_SEP);
152 /* ignore slashes after size; */
153 if (slash - path >= size)
154 slash = NULL;
156 ms = (slash != NULL) ? slash - semi : (int) strlen (semi);
157 ms = MIN ((unsigned int) ms, sizeof (encoding) - 1);
158 /* limit encoding size (ms) to path size (size) */
159 if (semi + ms > path + size)
160 ms = path + size - semi;
161 memcpy (encoding, semi, ms);
162 encoding[ms] = '\0';
164 if (is_supported_encoding (encoding))
165 coder = str_crt_conv_to (encoding);
167 if (coder != INVALID_CONV)
169 if (slash != NULL)
170 state = str_vfs_convert_to (coder, slash + 1, path + size - slash - 1, buffer);
171 str_close_conv (coder);
172 return state;
175 errno = EINVAL;
176 state = ESTR_FAILURE;
178 else
180 /* path can be translated whole at once */
181 state = str_vfs_convert_to (defcnv, path, size, buffer);
183 #else
184 (void) size;
185 (void) defcnv;
187 g_string_assign (buffer, path);
188 #endif /* HAVE_CHARSET */
190 return state;
193 /* --------------------------------------------------------------------------------------------- */
195 static struct vfs_openfile *
196 vfs_get_openfile (int handle)
198 struct vfs_openfile *h;
200 if (handle < VFS_FIRST_HANDLE || (guint) (handle - VFS_FIRST_HANDLE) >= vfs_openfiles->len)
201 return NULL;
203 h = (struct vfs_openfile *) g_ptr_array_index (vfs_openfiles, handle - VFS_FIRST_HANDLE);
204 if (h == NULL)
205 return NULL;
207 g_assert (h->handle == handle);
209 return h;
212 /* --------------------------------------------------------------------------------------------- */
214 static gboolean
215 vfs_test_current_dir (const vfs_path_t *vpath)
217 struct stat my_stat, my_stat2;
219 return (mc_global.vfs.cd_symlinks && mc_stat (vpath, &my_stat) == 0
220 && mc_stat (vfs_get_raw_current_dir (), &my_stat2) == 0
221 && my_stat.st_ino == my_stat2.st_ino && my_stat.st_dev == my_stat2.st_dev);
225 /* --------------------------------------------------------------------------------------------- */
226 /*** public functions ****************************************************************************/
227 /* --------------------------------------------------------------------------------------------- */
228 /** Free open file data for given file handle */
230 void
231 vfs_free_handle (int handle)
233 const int idx = handle - VFS_FIRST_HANDLE;
235 if (handle >= VFS_FIRST_HANDLE && (guint) idx < vfs_openfiles->len)
237 struct vfs_openfile *h;
239 h = (struct vfs_openfile *) g_ptr_array_index (vfs_openfiles, idx);
240 g_free (h);
241 g_ptr_array_index (vfs_openfiles, idx) = (void *) vfs_free_handle_list;
242 vfs_free_handle_list = idx;
247 /* --------------------------------------------------------------------------------------------- */
248 /** Find VFS class by file handle */
250 struct vfs_class *
251 vfs_class_find_by_handle (int handle, void **fsinfo)
253 struct vfs_openfile *h;
255 h = vfs_get_openfile (handle);
257 if (h == NULL)
258 return NULL;
260 if (fsinfo != NULL)
261 *fsinfo = h->fsinfo;
263 return h->vclass;
266 /* --------------------------------------------------------------------------------------------- */
269 * Create new VFS handle and put it to the list
273 vfs_new_handle (struct vfs_class *vclass, void *fsinfo)
275 struct vfs_openfile *h;
277 h = g_new (struct vfs_openfile, 1);
278 h->fsinfo = fsinfo;
279 h->vclass = vclass;
281 /* Allocate the first free handle */
282 h->handle = vfs_free_handle_list;
283 if (h->handle == -1)
285 /* No free allocated handles, allocate one */
286 h->handle = vfs_openfiles->len;
287 g_ptr_array_add (vfs_openfiles, h);
289 else
291 vfs_free_handle_list = (long) g_ptr_array_index (vfs_openfiles, vfs_free_handle_list);
292 g_ptr_array_index (vfs_openfiles, h->handle) = h;
295 h->handle += VFS_FIRST_HANDLE;
296 return h->handle;
299 /* --------------------------------------------------------------------------------------------- */
302 vfs_ferrno (struct vfs_class *vfs)
304 return vfs->ferrno ? (*vfs->ferrno) (vfs) : E_UNKNOWN;
305 /* Hope that error message is obscure enough ;-) */
308 /* --------------------------------------------------------------------------------------------- */
310 gboolean
311 vfs_register_class (struct vfs_class *vfs)
313 if (vfs->init != NULL) /* vfs has own initialization function */
314 if (!vfs->init (vfs)) /* but it failed */
315 return FALSE;
317 g_ptr_array_add (vfs__classes_list, vfs);
319 return TRUE;
322 /* --------------------------------------------------------------------------------------------- */
324 void
325 vfs_unregister_class (struct vfs_class *vfs)
327 if (vfs->done != NULL)
328 vfs->done (vfs);
330 g_ptr_array_remove (vfs__classes_list, vfs);
333 /* --------------------------------------------------------------------------------------------- */
334 /** Strip known vfs suffixes from a filename (possible improvement: strip
335 * suffix from last path component).
336 * \return a malloced string which has to be freed.
339 char *
340 vfs_strip_suffix_from_filename (const char *filename)
342 char *semi, *p;
344 if (filename == NULL)
345 vfs_die ("vfs_strip_suffix_from_path got NULL: impossible");
347 p = g_strdup (filename);
348 semi = g_strrstr (p, VFS_PATH_URL_DELIMITER);
349 if (semi != NULL)
351 char *vfs_prefix;
353 *semi = '\0';
354 vfs_prefix = strrchr (p, PATH_SEP);
355 if (vfs_prefix == NULL)
356 *semi = *VFS_PATH_URL_DELIMITER;
357 else
358 *vfs_prefix = '\0';
361 return p;
364 /* --------------------------------------------------------------------------------------------- */
366 const char *
367 vfs_translate_path (const char *path)
369 estr_t state;
371 g_string_set_size (vfs_str_buffer, 0);
372 state = _vfs_translate_path (path, -1, str_cnv_from_term, vfs_str_buffer);
373 return (state != ESTR_FAILURE) ? vfs_str_buffer->str : NULL;
376 /* --------------------------------------------------------------------------------------------- */
378 char *
379 vfs_translate_path_n (const char *path)
381 const char *result;
383 result = vfs_translate_path (path);
384 return g_strdup (result);
387 /* --------------------------------------------------------------------------------------------- */
389 * Get current directory without any OS calls.
391 * @return string contains current path
394 const char *
395 vfs_get_current_dir (void)
397 return current_path->str;
400 /* --------------------------------------------------------------------------------------------- */
402 * Get current directory without any OS calls.
404 * @return newly allocated string contains current path
407 char *
408 vfs_get_current_dir_n (void)
410 return g_strdup (current_path->str);
413 /* --------------------------------------------------------------------------------------------- */
415 * Get raw current directory object without any OS calls.
417 * @return object contain current path
420 const vfs_path_t *
421 vfs_get_raw_current_dir (void)
423 return current_path;
426 /* --------------------------------------------------------------------------------------------- */
428 * Set current directory object.
430 * @param vpath new path
432 void
433 vfs_set_raw_current_dir (const vfs_path_t *vpath)
435 vfs_path_free (current_path, TRUE);
436 current_path = (vfs_path_t *) vpath;
439 /* --------------------------------------------------------------------------------------------- */
440 /* Return TRUE is the current VFS class is local */
442 gboolean
443 vfs_current_is_local (void)
445 return (current_vfs->flags & VFSF_LOCAL) != 0;
448 /* --------------------------------------------------------------------------------------------- */
449 /* Return flags of the VFS class of the given filename */
451 vfs_flags_t
452 vfs_file_class_flags (const vfs_path_t *vpath)
454 const vfs_path_element_t *path_element;
456 path_element = vfs_path_get_by_index (vpath, -1);
457 if (!vfs_path_element_valid (path_element))
458 return VFSF_UNKNOWN;
460 return path_element->class->flags;
463 /* --------------------------------------------------------------------------------------------- */
465 void
466 vfs_init (void)
468 /* create the VFS handle arrays */
469 vfs__classes_list = g_ptr_array_new ();
471 /* create the VFS handle array */
472 vfs_openfiles = g_ptr_array_new ();
474 vfs_str_buffer = g_string_new ("");
476 mc_readdir_result = vfs_dirent_init (NULL, "", -1);
479 /* --------------------------------------------------------------------------------------------- */
481 void
482 vfs_setup_work_dir (void)
484 vfs_setup_cwd ();
486 /* FIXME: is we really need for this check? */
488 if (strlen (current_dir) > MC_MAXPATHLEN - 2)
489 vfs_die ("Current dir too long.\n");
492 current_vfs = VFS_CLASS (vfs_path_get_last_path_vfs (current_path));
495 /* --------------------------------------------------------------------------------------------- */
497 void
498 vfs_shut (void)
500 guint i;
502 vfs_gc_done ();
504 vfs_set_raw_current_dir (NULL);
506 for (i = 0; i < vfs__classes_list->len; i++)
508 struct vfs_class *vfs = VFS_CLASS (g_ptr_array_index (vfs__classes_list, i));
510 if (vfs->done != NULL)
511 vfs->done (vfs);
514 /* NULL-ize pointers to make unit tests happy */
515 g_ptr_array_free (vfs_openfiles, TRUE);
516 vfs_openfiles = NULL;
517 g_ptr_array_free (vfs__classes_list, TRUE);
518 vfs__classes_list = NULL;
519 g_string_free (vfs_str_buffer, TRUE);
520 vfs_str_buffer = NULL;
521 current_vfs = NULL;
522 vfs_free_handle_list = -1;
523 vfs_dirent_free (mc_readdir_result);
524 mc_readdir_result = NULL;
527 /* --------------------------------------------------------------------------------------------- */
529 * Init or create vfs_dirent structure
531 * @d vfs_dirent structure to init. If NULL, new structure is created.
532 * @fname file name
533 * @ino file inode number
535 * @return pointer to d if d isn't NULL, or pointer to newly created structure.
538 struct vfs_dirent *
539 vfs_dirent_init (struct vfs_dirent *d, const char *fname, ino_t ino)
541 struct vfs_dirent *ret = d;
543 if (ret == NULL)
544 ret = g_new0 (struct vfs_dirent, 1);
546 if (ret->d_name_str == NULL)
547 ret->d_name_str = g_string_sized_new (MC_MAXFILENAMELEN);
549 vfs_dirent_assign (ret, fname, ino);
551 return ret;
554 /* --------------------------------------------------------------------------------------------- */
556 * Assign members of vfs_dirent structure
558 * @d vfs_dirent structure for assignment
559 * @fname file name
560 * @ino file inode number
563 void
564 vfs_dirent_assign (struct vfs_dirent *d, const char *fname, ino_t ino)
566 g_string_assign (d->d_name_str, fname);
567 d->d_name = d->d_name_str->str;
568 d->d_len = d->d_name_str->len;
569 d->d_ino = ino;
572 /* --------------------------------------------------------------------------------------------- */
574 * Destroy vfs_dirent structure
576 * @d vfs_dirent structure to destroy.
579 void
580 vfs_dirent_free (struct vfs_dirent *d)
582 g_string_free (d->d_name_str, TRUE);
583 g_free (d);
586 /* --------------------------------------------------------------------------------------------- */
589 * These ones grab information from the VFS
590 * and handles them to an upper layer
593 void
594 vfs_fill_names (fill_names_f func)
596 guint i;
598 for (i = 0; i < vfs__classes_list->len; i++)
600 struct vfs_class *vfs = VFS_CLASS (g_ptr_array_index (vfs__classes_list, i));
602 if (vfs->fill_names != NULL)
603 vfs->fill_names (vfs, func);
607 /* --------------------------------------------------------------------------------------------- */
609 gboolean
610 vfs_file_is_local (const vfs_path_t *vpath)
612 return (vfs_file_class_flags (vpath) & VFSF_LOCAL) != 0;
615 /* --------------------------------------------------------------------------------------------- */
617 void
618 vfs_print_message (const char *msg, ...)
620 ev_vfs_print_message_t event_data;
621 va_list ap;
623 va_start (ap, msg);
624 event_data.msg = g_strdup_vprintf (msg, ap);
625 va_end (ap);
627 mc_event_raise (MCEVENT_GROUP_CORE, "vfs_print_message", (gpointer) & event_data);
630 /* --------------------------------------------------------------------------------------------- */
632 * If it's local, reread the current directory
633 * from the OS.
636 void
637 vfs_setup_cwd (void)
639 char *current_dir;
640 vfs_path_t *tmp_vpath;
641 const struct vfs_class *me;
643 if (vfs_get_raw_current_dir () == NULL)
645 current_dir = g_get_current_dir ();
646 vfs_set_raw_current_dir (vfs_path_from_str (current_dir));
647 g_free (current_dir);
649 current_dir = getenv ("PWD");
650 tmp_vpath = vfs_path_from_str (current_dir);
652 if (tmp_vpath != NULL)
654 if (vfs_test_current_dir (tmp_vpath))
655 vfs_set_raw_current_dir (tmp_vpath);
656 else
657 vfs_path_free (tmp_vpath, TRUE);
661 me = vfs_path_get_last_path_vfs (vfs_get_raw_current_dir ());
662 if ((me->flags & VFSF_LOCAL) != 0)
664 current_dir = g_get_current_dir ();
665 tmp_vpath = vfs_path_from_str (current_dir);
666 g_free (current_dir);
668 if (tmp_vpath != NULL)
670 /* One of directories in the path is not readable */
672 /* Check if it is O.K. to use the current_dir */
673 if (!vfs_test_current_dir (tmp_vpath))
674 vfs_set_raw_current_dir (tmp_vpath);
675 else
676 vfs_path_free (tmp_vpath, TRUE);
681 /* --------------------------------------------------------------------------------------------- */
683 * Return current directory. If it's local, reread the current directory
684 * from the OS.
687 char *
688 vfs_get_cwd (void)
690 vfs_setup_cwd ();
691 return vfs_get_current_dir_n ();
694 /* --------------------------------------------------------------------------------------------- */
696 * Preallocate space for file in new place for ensure that file
697 * will be fully copied with less fragmentation.
699 * @param dest_vfs_fd mc VFS file handler
700 * @param src_fsize source file size
701 * @param dest_fsize destination file size (if destination exists, otherwise should be 0)
703 * @return 0 if success and non-zero otherwise.
704 * Note: function doesn't touch errno global variable.
708 vfs_preallocate (int dest_vfs_fd, off_t src_fsize, off_t dest_fsize)
710 #ifndef HAVE_POSIX_FALLOCATE
711 (void) dest_vfs_fd;
712 (void) src_fsize;
713 (void) dest_fsize;
714 return 0;
716 #else /* HAVE_POSIX_FALLOCATE */
717 void *dest_fd = NULL;
718 struct vfs_class *dest_class;
720 if (src_fsize == 0)
721 return 0;
723 dest_class = vfs_class_find_by_handle (dest_vfs_fd, &dest_fd);
724 if ((dest_class->flags & VFSF_LOCAL) == 0 || dest_fd == NULL)
725 return 0;
727 return posix_fallocate (*(int *) dest_fd, dest_fsize, src_fsize - dest_fsize);
729 #endif /* HAVE_POSIX_FALLOCATE */
732 /* --------------------------------------------------------------------------------------------- */
735 vfs_clone_file (int dest_vfs_fd, int src_vfs_fd)
737 #ifdef FICLONE
738 void *dest_fd = NULL;
739 void *src_fd = NULL;
740 struct vfs_class *dest_class;
741 struct vfs_class *src_class;
743 dest_class = vfs_class_find_by_handle (dest_vfs_fd, &dest_fd);
744 if ((dest_class->flags & VFSF_LOCAL) == 0)
746 errno = ENOTSUP;
747 return (-1);
749 if (dest_fd == NULL)
751 errno = EBADF;
752 return (-1);
755 src_class = vfs_class_find_by_handle (src_vfs_fd, &src_fd);
756 if ((src_class->flags & VFSF_LOCAL) == 0)
758 errno = ENOTSUP;
759 return (-1);
761 if (src_fd == NULL)
763 errno = EBADF;
764 return (-1);
767 return ioctl (*(int *) dest_fd, FICLONE, *(int *) src_fd);
768 #else
769 (void) dest_vfs_fd;
770 (void) src_vfs_fd;
771 errno = ENOTSUP;
772 return (-1);
773 #endif
776 /* --------------------------------------------------------------------------------------------- */