/* Extract files from a tar archive. Copyright (C) 1988, 1992, 1993, 1994, 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004 Free Software Foundation, Inc. Written by John Gilmore, on 1985-11-19. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include #include #include #include #if HAVE_UTIME_H # include #else struct utimbuf { long actime; long modtime; }; #endif #include "common.h" bool we_are_root; /* true if our effective uid == 0 */ static mode_t newdir_umask; /* umask when creating new directories */ static mode_t current_umask; /* current umask (which is set to 0 if -p) */ /* Status of the permissions of a file that we are extracting. */ enum permstatus { /* This file may have existed already; its permissions are unknown. */ UNKNOWN_PERMSTATUS, /* This file was created using the permissions from the archive. */ ARCHIVED_PERMSTATUS, /* This is an intermediate directory; the archive did not specify its permissions. */ INTERDIR_PERMSTATUS }; /* List of directories whose statuses we need to extract after we've finished extracting their subsidiary files. If you consider each contiguous subsequence of elements of the form [D]?[^D]*, where [D] represents an element where AFTER_SYMLINKS is nonzero and [^D] represents an element where AFTER_SYMLINKS is zero, then the head of the subsequence has the longest name, and each non-head element in the prefix is an ancestor (in the directory hierarchy) of the preceding element. */ struct delayed_set_stat { struct delayed_set_stat *next; struct stat stat_info; size_t file_name_len; mode_t invert_permissions; enum permstatus permstatus; bool after_symlinks; char file_name[1]; }; static struct delayed_set_stat *delayed_set_stat_head; /* List of symbolic links whose creation we have delayed. */ struct delayed_symlink { /* The next delayed symbolic link in the list. */ struct delayed_symlink *next; /* The device, inode number and last-modified time of the placeholder. */ dev_t dev; ino_t ino; time_t mtime; /* The desired owner and group of the symbolic link. */ uid_t uid; gid_t gid; /* A list of sources for this symlink. The sources are all to be hard-linked together. */ struct string_list *sources; /* The desired target of the desired link. */ char target[1]; }; static struct delayed_symlink *delayed_symlink_head; struct string_list { struct string_list *next; char string[1]; }; /* Set up to extract files. */ void extr_init (void) { we_are_root = geteuid () == 0; same_permissions_option += we_are_root; same_owner_option += we_are_root; /* Save 'root device' to avoid purging mount points. FIXME: Should the same be done after handling -C option ? */ if (one_file_system_option) { struct stat st; char *dir = xgetcwd (); if (deref_stat (true, dir, &st)) stat_diag (dir); else root_device = st.st_dev; } /* Option -p clears the kernel umask, so it does not affect proper restoration of file permissions. New intermediate directories will comply with umask at start of program. */ newdir_umask = umask (0); if (0 < same_permissions_option) current_umask = 0; else { umask (newdir_umask); /* restore the kernel umask */ current_umask = newdir_umask; } } /* If restoring permissions, restore the mode for FILE_NAME from information given in *STAT_INFO (where *CUR_INFO gives the current status if CUR_INFO is nonzero); otherwise invert the INVERT_PERMISSIONS bits from the file's current permissions. PERMSTATUS specifies the status of the file's permissions. TYPEFLAG specifies the type of the file. */ static void set_mode (char const *file_name, struct stat const *stat_info, struct stat const *cur_info, mode_t invert_permissions, enum permstatus permstatus, char typeflag) { mode_t mode; if (0 < same_permissions_option && permstatus != INTERDIR_PERMSTATUS) { mode = stat_info->st_mode; /* If we created the file and it has a usual mode, then its mode is normally set correctly already. But on many hosts, some directories inherit the setgid bits from their parents, so we we must set directories' modes explicitly. */ if (permstatus == ARCHIVED_PERMSTATUS && ! (mode & ~ MODE_RWX) && typeflag != DIRTYPE && typeflag != GNUTYPE_DUMPDIR) return; } else if (! invert_permissions) return; else { /* We must inspect a directory's current permissions, since the directory may have inherited its setgid bit from its parent. INVERT_PERMISSIONS happens to be nonzero only for directories that we created, so there's no point optimizing this code for other cases. */ struct stat st; if (! cur_info) { if (stat (file_name, &st) != 0) { stat_error (file_name); return; } cur_info = &st; } mode = cur_info->st_mode ^ invert_permissions; } if (chmod (file_name, mode) != 0) chmod_error_details (file_name, mode); } /* Check time after successfully setting FILE_NAME's time stamp to T. */ static void check_time (char const *file_name, time_t t) { time_t now; if (t <= 0) WARN ((0, 0, _("%s: implausibly old time stamp %s"), file_name, tartime (t))); else if (start_time < t && (now = time (0)) < t) WARN ((0, 0, _("%s: time stamp %s is %lu s in the future"), file_name, tartime (t), (unsigned long) (t - now))); } /* Restore stat attributes (owner, group, mode and times) for FILE_NAME, using information given in *STAT_INFO. If CUR_INFO is nonzero, *CUR_INFO is the file's currernt status. If not restoring permissions, invert the INVERT_PERMISSIONS bits from the file's current permissions. PERMSTATUS specifies the status of the file's permissions. TYPEFLAG specifies the type of the file. */ /* FIXME: About proper restoration of symbolic link attributes, we still do not have it right. Pretesters' reports tell us we need further study and probably more configuration. For now, just use lchown if it exists, and punt for the rest. Sigh! */ static void set_stat (char const *file_name, struct stat const *stat_info, struct stat const *cur_info, mode_t invert_permissions, enum permstatus permstatus, char typeflag) { struct utimbuf utimbuf; if (typeflag != SYMTYPE) { /* We do the utime before the chmod because some versions of utime are broken and trash the modes of the file. */ if (! touch_option && permstatus != INTERDIR_PERMSTATUS) { /* We set the accessed time to `now', which is really the time we started extracting files, unless incremental_option is used, in which case .st_atime is used. */ /* FIXME: incremental_option should set ctime too, but how? */ if (incremental_option) utimbuf.actime = stat_info->st_atime; else utimbuf.actime = start_time; utimbuf.modtime = stat_info->st_mtime; if (utime (file_name, &utimbuf) < 0) utime_error (file_name); else { check_time (file_name, utimbuf.actime); check_time (file_name, utimbuf.modtime); } } /* Some systems allow non-root users to give files away. Once this done, it is not possible anymore to change file permissions, so we have to set permissions prior to possibly giving files away. */ set_mode (file_name, stat_info, cur_info, invert_permissions, permstatus, typeflag); } if (0 < same_owner_option && permstatus != INTERDIR_PERMSTATUS) { /* When lchown exists, it should be used to change the attributes of the symbolic link itself. In this case, a mere chown would change the attributes of the file the symbolic link is pointing to, and should be avoided. */ if (typeflag == SYMTYPE) { #if HAVE_LCHOWN if (lchown (file_name, stat_info->st_uid, stat_info->st_gid) < 0) chown_error_details (file_name, stat_info->st_uid, stat_info->st_gid); #endif } else { if (chown (file_name, stat_info->st_uid, stat_info->st_gid) < 0) chown_error_details (file_name, stat_info->st_uid, stat_info->st_gid); /* On a few systems, and in particular, those allowing to give files away, changing the owner or group destroys the suid or sgid bits. So let's attempt setting these bits once more. */ if (stat_info->st_mode & (S_ISUID | S_ISGID | S_ISVTX)) set_mode (file_name, stat_info, 0, invert_permissions, permstatus, typeflag); } } } /* Remember to restore stat attributes (owner, group, mode and times) for the directory FILE_NAME, using information given in *STAT_INFO, once we stop extracting files into that directory. If not restoring permissions, remember to invert the INVERT_PERMISSIONS bits from the file's current permissions. PERMSTATUS specifies the status of the file's permissions. */ static void delay_set_stat (char const *file_name, struct stat const *stat_info, mode_t invert_permissions, enum permstatus permstatus) { size_t file_name_len = strlen (file_name); struct delayed_set_stat *data = xmalloc (offsetof (struct delayed_set_stat, file_name) + file_name_len + 1); data->file_name_len = file_name_len; strcpy (data->file_name, file_name); data->invert_permissions = invert_permissions; data->permstatus = permstatus; data->after_symlinks = 0; data->stat_info = *stat_info; data->next = delayed_set_stat_head; delayed_set_stat_head = data; } /* Update the delayed_set_stat info for an intermediate directory created within the file name of DIR. The intermediate directory turned out to be the same as this directory, e.g. due to ".." or symbolic links. *DIR_STAT_INFO is the status of the directory. */ static void repair_delayed_set_stat (char const *dir, struct stat const *dir_stat_info) { struct delayed_set_stat *data; for (data = delayed_set_stat_head; data; data = data->next) { struct stat st; if (stat (data->file_name, &st) != 0) { stat_error (data->file_name); return; } if (st.st_dev == dir_stat_info->st_dev && st.st_ino == dir_stat_info->st_ino) { data->stat_info = current_stat_info.stat; data->invert_permissions = (MODE_RWX & (current_stat_info.stat.st_mode ^ st.st_mode)); data->permstatus = ARCHIVED_PERMSTATUS; return; } } ERROR ((0, 0, _("%s: Unexpected inconsistency when making directory"), quotearg_colon (dir))); } /* After a file/link/symlink/directory creation has failed, see if it's because some required directory was not present, and if so, create all required directories. Return non-zero if a directory was created. */ static int make_directories (char *file_name) { char *cursor0 = file_name + FILE_SYSTEM_PREFIX_LEN (file_name); char *cursor; /* points into the file name */ int did_something = 0; /* did we do anything yet? */ int mode; int invert_permissions; int status; for (cursor = cursor0; *cursor; cursor++) { if (! ISSLASH (*cursor)) continue; /* Avoid mkdir of empty string, if leading or double '/'. */ if (cursor == cursor0 || ISSLASH (cursor[-1])) continue; /* Avoid mkdir where last part of file name is "." or "..". */ if (cursor[-1] == '.' && (cursor == cursor0 + 1 || ISSLASH (cursor[-2]) || (cursor[-2] == '.' && (cursor == cursor0 + 2 || ISSLASH (cursor[-3]))))) continue; *cursor = '\0'; /* truncate the name there */ mode = MODE_RWX & ~ newdir_umask; invert_permissions = we_are_root ? 0 : MODE_WXUSR & ~ mode; status = mkdir (file_name, mode ^ invert_permissions); if (status == 0) { /* Create a struct delayed_set_stat even if invert_permissions is zero, because repair_delayed_set_stat may need to update the struct. */ delay_set_stat (file_name, ¤t_stat_info.stat /* ignored */, invert_permissions, INTERDIR_PERMSTATUS); print_for_mkdir (file_name, cursor - file_name, mode); did_something = 1; *cursor = '/'; continue; } *cursor = '/'; if (errno == EEXIST) continue; /* Directory already exists. */ else if ((errno == ENOSYS /* Automounted dirs on Solaris return this. Reported by Warren Hyde */ || ERRNO_IS_EACCES) /* Turbo C mkdir gives a funny errno. */ && access (file_name, W_OK) == 0) continue; /* Some other error in the mkdir. We return to the caller. */ break; } return did_something; /* tell them to retry if we made one */ } static bool file_newer_p (const char *file_name, struct tar_stat_info *tar_stat) { struct stat st; if (stat (file_name, &st)) { stat_warn (file_name); return true; /* Be on the safe side */ } if (!S_ISDIR (st.st_mode) && st.st_mtime >= tar_stat->stat.st_mtime) { return true; } return false; } /* Attempt repairing what went wrong with the extraction. Delete an already existing file or create missing intermediate directories. Return nonzero if we somewhat increased our chances at a successful extraction. errno is properly restored on zero return. */ static int maybe_recoverable (char *file_name, int *interdir_made) { int e = errno; if (*interdir_made) return 0; switch (errno) { case EEXIST: /* Remove an old file, if the options allow this. */ switch (old_files_option) { case KEEP_OLD_FILES: return 0; case KEEP_NEWER_FILES: if (file_newer_p (file_name, ¤t_stat_info)) { errno = e; return 0; } /* FALL THROUGH */ case DEFAULT_OLD_FILES: case NO_OVERWRITE_DIR_OLD_FILES: case OVERWRITE_OLD_FILES: { int r = remove_any_file (file_name, ORDINARY_REMOVE_OPTION); errno = EEXIST; return r; } case UNLINK_FIRST_OLD_FILES: break; } case ENOENT: /* Attempt creating missing intermediate directories. */ if (! make_directories (file_name)) { errno = ENOENT; return 0; } *interdir_made = 1; return 1; default: /* Just say we can't do anything about it... */ return 0; } } /* Fix the statuses of all directories whose statuses need fixing, and which are not ancestors of FILE_NAME. If AFTER_SYMLINKS is nonzero, do this for all such directories; otherwise, stop at the first directory that is marked to be fixed up only after delayed symlinks are applied. */ static void apply_nonancestor_delayed_set_stat (char const *file_name, bool after_symlinks) { size_t file_name_len = strlen (file_name); bool check_for_renamed_directories = 0; while (delayed_set_stat_head) { struct delayed_set_stat *data = delayed_set_stat_head; bool skip_this_one = 0; struct stat st; struct stat const *cur_info = 0; check_for_renamed_directories |= data->after_symlinks; if (after_symlinks < data->after_symlinks || (data->file_name_len < file_name_len && file_name[data->file_name_len] && (ISSLASH (file_name[data->file_name_len]) || ISSLASH (file_name[data->file_name_len - 1])) && memcmp (file_name, data->file_name, data->file_name_len) == 0)) break; if (check_for_renamed_directories) { cur_info = &st; if (stat (data->file_name, &st) != 0) { stat_error (data->file_name); skip_this_one = 1; } else if (! (st.st_dev == data->stat_info.st_dev && (st.st_ino == data->stat_info.st_ino))) { ERROR ((0, 0, _("%s: Directory renamed before its status could be extracted"), quotearg_colon (data->file_name))); skip_this_one = 1; } } if (! skip_this_one) set_stat (data->file_name, &data->stat_info, cur_info, data->invert_permissions, data->permstatus, DIRTYPE); delayed_set_stat_head = data->next; free (data); } } /* Extractor functions for various member types */ static int extract_dir (char *file_name, int typeflag) { int status; mode_t mode; int interdir_made = 0; if (incremental_option) /* Read the entry and delete files that aren't listed in the archive. */ purge_directory (file_name); else if (typeflag == GNUTYPE_DUMPDIR) skip_member (); mode = (current_stat_info.stat.st_mode | (we_are_root ? 0 : MODE_WXUSR)) & MODE_RWX; while ((status = mkdir (file_name, mode))) { if (errno == EEXIST && (interdir_made || old_files_option == DEFAULT_OLD_FILES || old_files_option == OVERWRITE_OLD_FILES)) { struct stat st; if (stat (file_name, &st) == 0) { if (interdir_made) { repair_delayed_set_stat (file_name, &st); return 0; } if (S_ISDIR (st.st_mode)) { mode = st.st_mode & ~ current_umask; break; } } errno = EEXIST; } if (maybe_recoverable (file_name, &interdir_made)) continue; if (errno != EEXIST) { mkdir_error (file_name); return 1; } break; } if (status == 0 || old_files_option == DEFAULT_OLD_FILES || old_files_option == OVERWRITE_OLD_FILES) delay_set_stat (file_name, ¤t_stat_info.stat, MODE_RWX & (mode ^ current_stat_info.stat.st_mode), (status == 0 ? ARCHIVED_PERMSTATUS : UNKNOWN_PERMSTATUS)); return status; } static int open_output_file (char *file_name, int typeflag) { int fd; int openflag = (O_WRONLY | O_BINARY | O_CREAT | (old_files_option == OVERWRITE_OLD_FILES ? O_TRUNC : O_EXCL)); mode_t mode = current_stat_info.stat.st_mode & MODE_RWX & ~ current_umask; #if O_CTG /* Contiguous files (on the Masscomp) have to specify the size in the open call that creates them. */ if (typeflag == CONTTYPE) fd = open (file_name, openflag | O_CTG, mode, current_stat_info.stat.st_size); else fd = open (file_name, openflag, mode); #else /* not O_CTG */ if (typeflag == CONTTYPE) { static int conttype_diagnosed; if (!conttype_diagnosed) { conttype_diagnosed = 1; WARN ((0, 0, _("Extracting contiguous files as regular files"))); } } fd = open (file_name, openflag, mode); #endif /* not O_CTG */ return fd; } static int extract_file (char *file_name, int typeflag) { int fd; off_t size; union block *data_block; int status; size_t count; size_t written; int interdir_made = 0; /* FIXME: deal with protection issues. */ if (to_stdout_option) fd = STDOUT_FILENO; else if (to_command_option) { fd = sys_exec_command (file_name, 'f', ¤t_stat_info); if (fd < 0) { skip_member (); return 0; } } else { do fd = open_output_file (file_name, typeflag); while (fd < 0 && maybe_recoverable (file_name, &interdir_made)); if (fd < 0) { open_error (file_name); return 1; } } if (current_stat_info.is_sparse) sparse_extract_file (fd, ¤t_stat_info, &size); else for (size = current_stat_info.stat.st_size; size > 0; ) { if (multi_volume_option) { assign_string (&save_name, current_stat_info.file_name); save_totsize = current_stat_info.stat.st_size; save_sizeleft = size; } /* Locate data, determine max length writeable, write it, block that we have used the data, then check if the write worked. */ data_block = find_next_block (); if (! data_block) { ERROR ((0, 0, _("Unexpected EOF in archive"))); break; /* FIXME: What happens, then? */ } written = available_space_after (data_block); if (written > size) written = size; errno = 0; count = full_write (fd, data_block->buffer, written); size -= written; set_next_block_after ((union block *) (data_block->buffer + written - 1)); if (count != written) { if (!to_command_option) write_error_details (file_name, count, written); /* FIXME: shouldn't we restore from backup? */ break; } } skip_file (size); if (multi_volume_option) assign_string (&save_name, 0); /* If writing to stdout, don't try to do anything to the filename; it doesn't exist, or we don't want to touch it anyway. */ if (to_stdout_option) return 0; status = close (fd); if (status < 0) close_error (file_name); if (to_command_option) sys_wait_command (); else set_stat (file_name, ¤t_stat_info.stat, 0, 0, (old_files_option == OVERWRITE_OLD_FILES ? UNKNOWN_PERMSTATUS : ARCHIVED_PERMSTATUS), typeflag); return status; } static int extract_link (char *file_name, int typeflag) { char const *link_name = safer_name_suffix (current_stat_info.link_name, true); int interdir_made = 0; do { struct stat st1, st2; int e; int status = link (link_name, file_name); e = errno; if (status == 0) { struct delayed_symlink *ds = delayed_symlink_head; if (ds && lstat (link_name, &st1) == 0) for (; ds; ds = ds->next) if (ds->dev == st1.st_dev && ds->ino == st1.st_ino && ds->mtime == st1.st_mtime) { struct string_list *p = xmalloc (offsetof (struct string_list, string) + strlen (file_name) + 1); strcpy (p->string, file_name); p->next = ds->sources; ds->sources = p; break; } return 0; } else if ((e == EEXIST && strcmp (link_name, file_name) == 0) || (lstat (link_name, &st1) == 0 && lstat (file_name, &st2) == 0 && st1.st_dev == st2.st_dev && st1.st_ino == st2.st_ino)) return 0; errno = e; } while (maybe_recoverable (file_name, &interdir_made)); if (!(incremental_option && errno == EEXIST)) { link_error (link_name, file_name); return 1; } return 0; } static int extract_symlink (char *file_name, int typeflag) { #ifdef HAVE_SYMLINK int status, fd; int interdir_made = 0; if (absolute_names_option || ! (IS_ABSOLUTE_FILE_NAME (current_stat_info.link_name) || contains_dot_dot (current_stat_info.link_name))) { while ((status = symlink (current_stat_info.link_name, file_name))) if (!maybe_recoverable (file_name, &interdir_made)) break; if (status == 0) set_stat (file_name, ¤t_stat_info.stat, 0, 0, 0, SYMTYPE); else symlink_error (current_stat_info.link_name, file_name); } else { /* This symbolic link is potentially dangerous. Don't create it now; instead, create a placeholder file, which will be replaced after other extraction is done. */ struct stat st; while ((fd = open (file_name, O_WRONLY | O_CREAT | O_EXCL, 0)) < 0) if (! maybe_recoverable (file_name, &interdir_made)) break; status = -1; if (fd < 0) open_error (file_name); else if (fstat (fd, &st) != 0) { stat_error (file_name); close (fd); } else if (close (fd) != 0) close_error (file_name); else { struct delayed_set_stat *h; struct delayed_symlink *p = xmalloc (offsetof (struct delayed_symlink, target) + strlen (current_stat_info.link_name) + 1); p->next = delayed_symlink_head; delayed_symlink_head = p; p->dev = st.st_dev; p->ino = st.st_ino; p->mtime = st.st_mtime; p->uid = current_stat_info.stat.st_uid; p->gid = current_stat_info.stat.st_gid; p->sources = xmalloc (offsetof (struct string_list, string) + strlen (file_name) + 1); p->sources->next = 0; strcpy (p->sources->string, file_name); strcpy (p->target, current_stat_info.link_name); h = delayed_set_stat_head; if (h && ! h->after_symlinks && strncmp (file_name, h->file_name, h->file_name_len) == 0 && ISSLASH (file_name[h->file_name_len]) && (base_name (file_name) == file_name + h->file_name_len + 1)) { do { h->after_symlinks = 1; if (stat (h->file_name, &st) != 0) stat_error (h->file_name); else { h->stat_info.st_dev = st.st_dev; h->stat_info.st_ino = st.st_ino; } } while ((h = h->next) && ! h->after_symlinks); } status = 0; } } return status; #else static int warned_once; if (!warned_once) { warned_once = 1; WARN ((0, 0, _("Attempting extraction of symbolic links as hard links"))); } return extract_link (file_name, typeflag); #endif } #if S_IFCHR || S_IFBLK static int extract_node (char *file_name, int typeflag) { int status; int interdir_made = 0; do status = mknod (file_name, current_stat_info.stat.st_mode, current_stat_info.stat.st_rdev); while (status && maybe_recoverable (file_name, &interdir_made)); if (status != 0) mknod_error (file_name); else set_stat (file_name, ¤t_stat_info.stat, 0, 0, ARCHIVED_PERMSTATUS, typeflag); return status; } #endif #if HAVE_MKFIFO || defined mkfifo static int extract_fifo (char *file_name, int typeflag) { int status; int interdir_made = 0; while ((status = mkfifo (file_name, current_stat_info.stat.st_mode))) if (!maybe_recoverable (file_name, &interdir_made)) break; if (status == 0) set_stat (file_name, ¤t_stat_info.stat, NULL, 0, ARCHIVED_PERMSTATUS, typeflag); else mkfifo_error (file_name); return status; } #endif static int extract_mangle_wrapper (char *file_name, int typeflag) { extract_mangle (); return 0; } static int extract_failure (char *file_name, int typeflag) { return 1; } typedef int (*tar_extractor_t) (char *file_name, int typeflag); /* Prepare to extract a file. Find extractor function. Return zero if extraction should not proceed. */ static int prepare_to_extract (char const *file_name, int typeflag, tar_extractor_t *fun) { int rc = 1; if (EXTRACT_OVER_PIPE) rc = 0; /* Select the extractor */ switch (typeflag) { case GNUTYPE_SPARSE: *fun = extract_file; rc = 1; break; case AREGTYPE: case REGTYPE: case CONTTYPE: /* Appears to be a file. But BSD tar uses the convention that a slash suffix means a directory. */ if (current_stat_info.had_trailing_slash) *fun = extract_dir; else { *fun = extract_file; rc = 1; } break; case SYMTYPE: *fun = extract_symlink; break; case LNKTYPE: *fun = extract_link; break; #if S_IFCHR case CHRTYPE: current_stat_info.stat.st_mode |= S_IFCHR; *fun = extract_node; break; #endif #if S_IFBLK case BLKTYPE: current_stat_info.stat.st_mode |= S_IFBLK; *fun = extract_node; break; #endif #if HAVE_MKFIFO || defined mkfifo case FIFOTYPE: *fun = extract_fifo; break; #endif case DIRTYPE: case GNUTYPE_DUMPDIR: *fun = extract_dir; break; case GNUTYPE_VOLHDR: if (verbose_option) fprintf (stdlis, _("Reading %s\n"), quote (current_stat_info.file_name)); *fun = NULL; break; case GNUTYPE_NAMES: *fun = extract_mangle_wrapper; break; case GNUTYPE_MULTIVOL: ERROR ((0, 0, _("%s: Cannot extract -- file is continued from another volume"), quotearg_colon (current_stat_info.file_name))); *fun = extract_failure; break; case GNUTYPE_LONGNAME: case GNUTYPE_LONGLINK: ERROR ((0, 0, _("Unexpected long name header"))); *fun = extract_failure; break; default: WARN ((0, 0, _("%s: Unknown file type '%c', extracted as normal file"), quotearg_colon (file_name), typeflag)); *fun = extract_file; } /* Determine whether the extraction should proceed */ if (rc == 0) return 0; switch (old_files_option) { case UNLINK_FIRST_OLD_FILES: if (!remove_any_file (file_name, recursive_unlink_option ? RECURSIVE_REMOVE_OPTION : ORDINARY_REMOVE_OPTION) && errno && errno != ENOENT) { unlink_error (file_name); return 0; } break; case KEEP_NEWER_FILES: if (file_newer_p (file_name, ¤t_stat_info)) { WARN ((0, 0, _("Current %s is newer"), quote (file_name))); return 0; } break; default: break; } return 1; } /* Extract a file from the archive. */ void extract_archive (void) { char typeflag; char *file_name; tar_extractor_t fun; set_next_block_after (current_header); decode_header (current_header, ¤t_stat_info, ¤t_format, 1); if (interactive_option && !confirm ("extract", current_stat_info.file_name)) { skip_member (); return; } /* Print the block from current_header and current_stat. */ if (verbose_option) print_header (¤t_stat_info, -1); file_name = safer_name_suffix (current_stat_info.file_name, false); if (strip_name_components) { size_t prefix_len = stripped_prefix_len (file_name, strip_name_components); if (prefix_len == (size_t) -1) { skip_member (); return; } file_name += prefix_len; } apply_nonancestor_delayed_set_stat (file_name, 0); /* Take a safety backup of a previously existing file. */ if (backup_option) if (!maybe_backup_file (file_name, 0)) { int e = errno; ERROR ((0, e, _("%s: Was unable to backup this file"), quotearg_colon (file_name))); skip_member (); return; } /* Extract the archive entry according to its type. */ /* KLUDGE */ typeflag = sparse_member_p (¤t_stat_info) ? GNUTYPE_SPARSE : current_header->header.typeflag; if (prepare_to_extract (file_name, typeflag, &fun)) { if (fun && (*fun) (file_name, typeflag) && backup_option) undo_last_backup (); } else skip_member (); } /* Extract the symbolic links whose final extraction were delayed. */ static void apply_delayed_symlinks (void) { struct delayed_symlink *ds; for (ds = delayed_symlink_head; ds; ) { struct string_list *sources = ds->sources; char const *valid_source = 0; for (sources = ds->sources; sources; sources = sources->next) { char const *source = sources->string; struct stat st; /* Make sure the placeholder file is still there. If not, don't create a symlink, as the placeholder was probably removed by a later extraction. */ if (lstat (source, &st) == 0 && st.st_dev == ds->dev && st.st_ino == ds->ino && st.st_mtime == ds->mtime) { /* Unlink the placeholder, then create a hard link if possible, a symbolic link otherwise. */ if (unlink (source) != 0) unlink_error (source); else if (valid_source && link (valid_source, source) == 0) ; else if (symlink (ds->target, source) != 0) symlink_error (ds->target, source); else { valid_source = source; st.st_uid = ds->uid; st.st_gid = ds->gid; set_stat (source, &st, 0, 0, 0, SYMTYPE); } } } for (sources = ds->sources; sources; ) { struct string_list *next = sources->next; free (sources); sources = next; } { struct delayed_symlink *next = ds->next; free (ds); ds = next; } } delayed_symlink_head = 0; } /* Finish the extraction of an archive. */ void extract_finish (void) { /* First, fix the status of ordinary directories that need fixing. */ apply_nonancestor_delayed_set_stat ("", 0); /* Then, apply delayed symlinks, so that they don't affect delayed directory status-setting for ordinary directories. */ apply_delayed_symlinks (); /* Finally, fix the status of directories that are ancestors of delayed symlinks. */ apply_nonancestor_delayed_set_stat ("", 1); } void fatal_exit (void) { extract_finish (); error (TAREXIT_FAILURE, 0, _("Error is not recoverable: exiting now")); abort (); } void xalloc_die (void) { error (0, 0, "%s", _("memory exhausted")); fatal_exit (); }