1/* Common declarations for the tar program.
2
3   Copyright (C) 1988, 1992, 1993, 1994, 1996, 1997, 1999, 2000, 2001,
4   2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
5
6   This program is free software; you can redistribute it and/or modify it
7   under the terms of the GNU General Public License as published by the
8   Free Software Foundation; either version 2, or (at your option) any later
9   version.
10
11   This program is distributed in the hope that it will be useful, but
12   WITHOUT ANY WARRANTY; without even the implied warranty of
13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
14   Public License for more details.
15
16   You should have received a copy of the GNU General Public License along
17   with this program; if not, write to the Free Software Foundation, Inc.,
18   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
19
20/* Declare the GNU tar archive format.  */
21#include "tar.h"
22
23#include <TargetConditionals.h>
24#if defined(__has_include) && __has_include(<quarantine.h>)
25#define HAVE_QUARANTINE 1
26#else
27#define HAVE_QUARANTINE 0
28#endif
29
30#if HAVE_QUARANTINE
31#include <quarantine.h>
32#endif
33
34/* The checksum field is filled with this while the checksum is computed.  */
35#define CHKBLANKS	"        "	/* 8 blanks, no null */
36
37/* Some constants from POSIX are given names.  */
38#define NAME_FIELD_SIZE   100
39#define PREFIX_FIELD_SIZE 155
40#define UNAME_FIELD_SIZE   32
41#define GNAME_FIELD_SIZE   32
42
43
44
45/* Some various global definitions.  */
46
47/* Name of file to use for interacting with user.  */
48
49/* GLOBAL is defined to empty in tar.c only, and left alone in other *.c
50   modules.  Here, we merely set it to "extern" if it is not already set.
51   GNU tar does depend on the system loader to preset all GLOBAL variables to
52   neutral (or zero) values, explicit initialization is usually not done.  */
53#ifndef GLOBAL
54# define GLOBAL extern
55#endif
56
57#define TAREXIT_SUCCESS PAXEXIT_SUCCESS
58#define TAREXIT_DIFFERS PAXEXIT_DIFFERS
59#define TAREXIT_FAILURE PAXEXIT_FAILURE
60
61
62#include "arith.h"
63#include <backupfile.h>
64#include <exclude.h>
65#include <full-write.h>
66#include <modechange.h>
67#include <quote.h>
68#include <safe-read.h>
69#include <stat-time.h>
70#include <timespec.h>
71#define obstack_chunk_alloc xmalloc
72#define obstack_chunk_free free
73#include <obstack.h>
74
75#include <paxlib.h>
76
77/* Log base 2 of common values.  */
78#define LG_8 3
79#define LG_64 6
80#define LG_256 8
81
82/* Information gleaned from the command line.  */
83
84/* Name of this program.  */
85GLOBAL const char *program_name;
86
87/* Main command option.  */
88
89enum subcommand
90{
91  UNKNOWN_SUBCOMMAND,		/* none of the following */
92  APPEND_SUBCOMMAND,		/* -r */
93  CAT_SUBCOMMAND,		/* -A */
94  CREATE_SUBCOMMAND,		/* -c */
95  DELETE_SUBCOMMAND,		/* -D */
96  DIFF_SUBCOMMAND,		/* -d */
97  EXTRACT_SUBCOMMAND,		/* -x */
98  LIST_SUBCOMMAND,		/* -t */
99  UPDATE_SUBCOMMAND		/* -u */
100};
101
102GLOBAL enum subcommand subcommand_option;
103
104/* Selected format for output archive.  */
105GLOBAL enum archive_format archive_format;
106
107/* Either NL or NUL, as decided by the --null option.  */
108GLOBAL char filename_terminator;
109
110/* Size of each record, once in blocks, once in bytes.  Those two variables
111   are always related, the second being BLOCKSIZE times the first.  They do
112   not have _option in their name, even if their values is derived from
113   option decoding, as these are especially important in tar.  */
114GLOBAL int blocking_factor;
115GLOBAL size_t record_size;
116
117GLOBAL bool absolute_names_option;
118
119/* Display file times in UTC */
120GLOBAL bool utc_option;
121
122/* This variable tells how to interpret newer_mtime_option, below.  If zero,
123   files get archived if their mtime is not less than newer_mtime_option.
124   If nonzero, files get archived if *either* their ctime or mtime is not less
125   than newer_mtime_option.  */
126GLOBAL int after_date_option;
127
128enum atime_preserve
129{
130  no_atime_preserve,
131  replace_atime_preserve,
132  system_atime_preserve
133};
134GLOBAL enum atime_preserve atime_preserve_option;
135
136GLOBAL bool backup_option;
137
138/* Type of backups being made.  */
139GLOBAL enum backup_type backup_type;
140
141GLOBAL bool block_number_option;
142
143GLOBAL unsigned checkpoint_option;
144
145enum checkpoint_style
146  {
147    checkpoint_text,
148    checkpoint_dot
149  };
150
151GLOBAL enum checkpoint_style checkpoint_style;
152
153/* Specified name of compression program, or "gzip" as implied by -z.  */
154GLOBAL const char *use_compress_program_option;
155
156GLOBAL bool dereference_option;
157
158/* Print a message if not all links are dumped */
159GLOBAL int check_links_option;
160
161/* Patterns that match file names to be excluded.  */
162GLOBAL struct exclude *excluded;
163
164enum exclusion_tag_type
165  {
166    exclusion_tag_none,
167     /* Exclude the directory contents, but preserve the directory
168	itself and the exclusion tag file */
169    exclusion_tag_contents,
170    /* Exclude everything below the directory, preserving the directory
171       itself */
172    exclusion_tag_under,
173    /* Exclude entire directory  */
174    exclusion_tag_all,
175  };
176
177/* Specified value to be put into tar file in place of stat () results, or
178   just -1 if such an override should not take place.  */
179GLOBAL gid_t group_option;
180
181GLOBAL bool ignore_failed_read_option;
182
183GLOBAL bool ignore_zeros_option;
184
185GLOBAL bool incremental_option;
186
187/* Specified name of script to run at end of each tape change.  */
188GLOBAL const char *info_script_option;
189
190GLOBAL bool interactive_option;
191
192/* If nonzero, extract only Nth occurrence of each named file */
193GLOBAL uintmax_t occurrence_option;
194
195enum old_files
196{
197  DEFAULT_OLD_FILES,          /* default */
198  NO_OVERWRITE_DIR_OLD_FILES, /* --no-overwrite-dir */
199  OVERWRITE_OLD_FILES,        /* --overwrite */
200  UNLINK_FIRST_OLD_FILES,     /* --unlink-first */
201  KEEP_OLD_FILES,             /* --keep-old-files */
202  KEEP_NEWER_FILES	      /* --keep-newer-files */
203};
204GLOBAL enum old_files old_files_option;
205
206/* Specified file name for incremental list.  */
207GLOBAL const char *listed_incremental_option;
208
209/* Specified mode change string.  */
210GLOBAL struct mode_change *mode_option;
211
212/* Initial umask, if needed for mode change string.  */
213GLOBAL mode_t initial_umask;
214
215GLOBAL bool multi_volume_option;
216
217/* Specified threshold date and time.  Files having an older time stamp
218   do not get archived (also see after_date_option above).  */
219GLOBAL struct timespec newer_mtime_option;
220
221/* If true, override actual mtime (see below) */
222GLOBAL bool set_mtime_option;
223/* Value to be put in mtime header field instead of the actual mtime */
224GLOBAL struct timespec mtime_option;
225
226/* Return true if newer_mtime_option is initialized.  */
227#define NEWER_OPTION_INITIALIZED(opt) (0 <= (opt).tv_nsec)
228
229/* Return true if the struct stat ST's M time is less than
230   newer_mtime_option.  */
231#define OLDER_STAT_TIME(st, m) \
232  (timespec_cmp (get_stat_##m##time (&(st)), newer_mtime_option) < 0)
233
234/* Likewise, for struct tar_stat_info ST.  */
235#define OLDER_TAR_STAT_TIME(st, m) \
236  (timespec_cmp ((st).m##time, newer_mtime_option) < 0)
237
238/* Zero if there is no recursion, otherwise FNM_LEADING_DIR.  */
239GLOBAL int recursion_option;
240
241GLOBAL bool numeric_owner_option;
242
243GLOBAL bool one_file_system_option;
244
245/* Specified value to be put into tar file in place of stat () results, or
246   just -1 if such an override should not take place.  */
247GLOBAL uid_t owner_option;
248
249GLOBAL bool recursive_unlink_option;
250
251GLOBAL bool read_full_records_option;
252
253GLOBAL bool remove_files_option;
254
255/* Specified rmt command.  */
256GLOBAL const char *rmt_command_option;
257
258/* Specified remote shell command.  */
259GLOBAL const char *rsh_command_option;
260
261GLOBAL bool same_order_option;
262
263/* If positive, preserve ownership when extracting.  */
264GLOBAL int same_owner_option;
265
266/* If positive, preserve permissions when extracting.  */
267GLOBAL int same_permissions_option;
268
269/* When set, strip the given number of file name components from the file name
270   before extracting */
271GLOBAL size_t strip_name_components;
272
273GLOBAL bool show_omitted_dirs_option;
274
275GLOBAL bool sparse_option;
276GLOBAL unsigned tar_sparse_major;
277GLOBAL unsigned tar_sparse_minor;
278
279GLOBAL bool starting_file_option;
280
281/* Specified maximum byte length of each tape volume (multiple of 1024).  */
282GLOBAL tarlong tape_length_option;
283
284GLOBAL bool to_stdout_option;
285
286GLOBAL bool totals_option;
287
288GLOBAL bool touch_option;
289
290GLOBAL char *to_command_option;
291GLOBAL bool ignore_command_error_option;
292
293/* Restrict some potentially harmful tar options */
294GLOBAL bool restrict_option;
295
296/* Return true if the extracted files are not being written to disk */
297#define EXTRACT_OVER_PIPE (to_stdout_option || to_command_option)
298
299/* Count how many times the option has been set, multiple setting yields
300   more verbose behavior.  Value 0 means no verbosity, 1 means file name
301   only, 2 means file name and all attributes.  More than 2 is just like 2.  */
302GLOBAL int verbose_option;
303
304GLOBAL bool verify_option;
305
306/* Specified name of file containing the volume number.  */
307GLOBAL const char *volno_file_option;
308
309/* Specified value or pattern.  */
310GLOBAL const char *volume_label_option;
311
312/* Other global variables.  */
313
314/* File descriptor for archive file.  */
315GLOBAL int archive;
316#if HAVE_QUARANTINE
317GLOBAL qtn_file_t archive_qtn_file;
318#endif
319
320/* Nonzero when outputting to /dev/null.  */
321GLOBAL bool dev_null_output;
322
323/* Timestamps: */
324GLOBAL struct timespec start_time;        /* when we started execution */
325GLOBAL struct timespec volume_start_time; /* when the current volume was
326					     opened*/
327GLOBAL struct timespec last_stat_time;    /* when the statistics was last
328					     computed */
329
330GLOBAL struct tar_stat_info current_stat_info;
331
332/* List of tape drive names, number of such tape drives, allocated number,
333   and current cursor in list.  */
334GLOBAL const char **archive_name_array;
335GLOBAL size_t archive_names;
336GLOBAL size_t allocated_archive_names;
337GLOBAL const char **archive_name_cursor;
338
339/* Output index file name.  */
340GLOBAL char const *index_file_name;
341
342/* Structure for keeping track of filenames and lists thereof.  */
343struct name
344  {
345    struct name *next;          /* Link to the next element */
346    int change_dir;		/* Number of the directory to change to.
347				   Set with the -C option. */
348    uintmax_t found_count;	/* number of times a matching file has
349				   been found */
350    int matching_flags;		/* this name is a regexp, not literal */
351    char const *dir_contents;	/* for incremental_option */
352
353    size_t length;		/* cached strlen(name) */
354    char name[1];
355  };
356
357/* Obnoxious test to see if dimwit is trying to dump the archive.  */
358GLOBAL dev_t ar_dev;
359GLOBAL ino_t ar_ino;
360
361GLOBAL bool seekable_archive;
362
363GLOBAL dev_t root_device;
364
365/* Unquote filenames */
366GLOBAL bool unquote_option;
367
368GLOBAL bool test_label_option; /* Test archive volume label and exit */
369
370/* Show file or archive names after transformation.
371   In particular, when creating archive in verbose mode, list member names
372   as stored in the archive */
373GLOBAL bool show_transformed_names_option;
374
375/* Delay setting modification times and permissions of extracted directories
376   until the end of extraction. This variable helps correctly restore directory
377   timestamps from archives with an unusual member order. It is automatically
378   set for incremental archives. */
379GLOBAL bool delay_directory_restore_option;
380
381/* Warn about implicit use of the wildcards in command line arguments.
382   (Default for tar prior to 1.15.91, but changed afterwards */
383GLOBAL bool warn_regex_usage;
384
385/* Declarations for each module.  */
386
387/* FIXME: compare.c should not directly handle the following variable,
388   instead, this should be done in buffer.c only.  */
389
390enum access_mode
391{
392  ACCESS_READ,
393  ACCESS_WRITE,
394  ACCESS_UPDATE
395};
396extern enum access_mode access_mode;
397
398/* Module buffer.c.  */
399
400extern FILE *stdlis;
401extern bool write_archive_to_stdout;
402extern char *volume_label;
403extern char *continued_file_name;
404extern uintmax_t continued_file_size;
405extern uintmax_t continued_file_offset;
406
407size_t available_space_after (union block *pointer);
408off_t current_block_ordinal (void);
409void close_archive (void);
410void closeout_volume_number (void);
411void compute_duration (void);
412union block *find_next_block (void);
413void flush_read (void);
414void flush_write (void);
415void flush_archive (void);
416void init_volume_number (void);
417void open_archive (enum access_mode mode);
418void print_total_stats (void);
419void reset_eof (void);
420void set_next_block_after (union block *block);
421void clear_read_error_count (void);
422void xclose (int fd);
423void archive_write_error (ssize_t status) __attribute__ ((noreturn));
424void archive_read_error (void);
425off_t seek_archive (off_t size);
426void set_start_time (void);
427
428void mv_begin (struct tar_stat_info *st);
429void mv_end (void);
430void mv_total_size (off_t size);
431void mv_size_left (off_t size);
432
433void buffer_write_global_xheader (void);
434
435/* Module create.c.  */
436
437enum dump_status
438  {
439    dump_status_ok,
440    dump_status_short,
441    dump_status_fail,
442    dump_status_not_implemented
443  };
444
445void add_exclusion_tag (const char *name, enum exclusion_tag_type type,
446			bool (*)(const char*));
447bool cachedir_file_p (const char *name);
448
449bool file_dumpable_p (struct tar_stat_info *st);
450void create_archive (void);
451void pad_archive (off_t size_left);
452void dump_file (const char *st, int top_level, dev_t parent_device);
453union block *start_header (struct tar_stat_info *st);
454void finish_header (struct tar_stat_info *st, union block *header,
455		    off_t block_ordinal);
456void simple_finish_header (union block *header);
457union block * write_extended (bool global, struct tar_stat_info *st,
458			      union block *old_header);
459union block *start_private_header (const char *name, size_t size);
460void write_eot (void);
461void check_links (void);
462
463#define GID_TO_CHARS(val, where) gid_to_chars (val, where, sizeof (where))
464#define MAJOR_TO_CHARS(val, where) major_to_chars (val, where, sizeof (where))
465#define MINOR_TO_CHARS(val, where) minor_to_chars (val, where, sizeof (where))
466#define MODE_TO_CHARS(val, where) mode_to_chars (val, where, sizeof (where))
467#define OFF_TO_CHARS(val, where) off_to_chars (val, where, sizeof (where))
468#define SIZE_TO_CHARS(val, where) size_to_chars (val, where, sizeof (where))
469#define TIME_TO_CHARS(val, where) time_to_chars (val, where, sizeof (where))
470#define UID_TO_CHARS(val, where) uid_to_chars (val, where, sizeof (where))
471#define UINTMAX_TO_CHARS(val, where) uintmax_to_chars (val, where, sizeof (where))
472#define UNAME_TO_CHARS(name,buf) string_to_chars (name, buf, sizeof(buf))
473#define GNAME_TO_CHARS(name,buf) string_to_chars (name, buf, sizeof(buf))
474
475bool gid_to_chars (gid_t gid, char *buf, size_t size);
476bool major_to_chars (major_t m, char *buf, size_t size);
477bool minor_to_chars (minor_t m, char *buf, size_t size);
478bool mode_to_chars (mode_t m, char *buf, size_t size);
479bool off_to_chars (off_t off, char *buf, size_t size);
480bool size_to_chars (size_t v, char *buf, size_t size);
481bool time_to_chars (time_t t, char *buf, size_t size);
482bool uid_to_chars (uid_t uid, char *buf, size_t size);
483bool uintmax_to_chars (uintmax_t v, char *buf, size_t size);
484void string_to_chars (char const *s, char *buf, size_t size);
485
486/* Module diffarch.c.  */
487
488extern bool now_verifying;
489
490void diff_archive (void);
491void diff_init (void);
492void verify_volume (void);
493
494/* Module extract.c.  */
495
496void extr_init (void);
497void extract_archive (void);
498void extract_finish (void);
499bool rename_directory (char *src, char *dst);
500
501/* Module delete.c.  */
502
503void delete_archive_members (void);
504
505/* Module incremen.c.  */
506
507char *get_directory_contents (char *dir_name, dev_t device);
508const char *append_incremental_renames (const char *dump);
509void read_directory_file (void);
510void write_directory_file (void);
511void purge_directory (char const *directory_name);
512void list_dumpdir (char *buffer, size_t size);
513void update_parent_directory (const char *name);
514
515size_t dumpdir_size (const char *p);
516bool is_dumpdir (struct tar_stat_info *stat_info);
517
518/* Module list.c.  */
519
520enum read_header
521{
522  HEADER_STILL_UNREAD,		/* for when read_header has not been called */
523  HEADER_SUCCESS,		/* header successfully read and checksummed */
524  HEADER_SUCCESS_EXTENDED,	/* likewise, but we got an extended header */
525  HEADER_ZERO_BLOCK,		/* zero block where header expected */
526  HEADER_END_OF_FILE,		/* true end of file while header expected */
527  HEADER_FAILURE		/* ill-formed header, or bad checksum */
528};
529
530extern union block *current_header;
531extern enum archive_format current_format;
532extern size_t recent_long_name_blocks;
533extern size_t recent_long_link_blocks;
534
535void decode_header (union block *header, struct tar_stat_info *stat_info,
536		    enum archive_format *format_pointer, int do_user_group);
537char const *tartime (struct timespec t, bool full_time);
538
539#define GID_FROM_HEADER(where) gid_from_header (where, sizeof (where))
540#define MAJOR_FROM_HEADER(where) major_from_header (where, sizeof (where))
541#define MINOR_FROM_HEADER(where) minor_from_header (where, sizeof (where))
542#define MODE_FROM_HEADER(where) mode_from_header (where, sizeof (where))
543#define OFF_FROM_HEADER(where) off_from_header (where, sizeof (where))
544#define SIZE_FROM_HEADER(where) size_from_header (where, sizeof (where))
545#define TIME_FROM_HEADER(where) time_from_header (where, sizeof (where))
546#define UID_FROM_HEADER(where) uid_from_header (where, sizeof (where))
547#define UINTMAX_FROM_HEADER(where) uintmax_from_header (where, sizeof (where))
548
549gid_t gid_from_header (const char *buf, size_t size);
550major_t major_from_header (const char *buf, size_t size);
551minor_t minor_from_header (const char *buf, size_t size);
552mode_t mode_from_header (const char *buf, size_t size);
553off_t off_from_header (const char *buf, size_t size);
554size_t size_from_header (const char *buf, size_t size);
555time_t time_from_header (const char *buf, size_t size);
556uid_t uid_from_header (const char *buf, size_t size);
557uintmax_t uintmax_from_header (const char * buf, size_t size);
558
559void list_archive (void);
560void print_for_mkdir (char *dirname, int length, mode_t mode);
561void print_header (struct tar_stat_info *st, off_t block_ordinal);
562void read_and (void (*do_something) (void));
563enum read_header read_header_primitive (bool raw_extended_headers,
564					struct tar_stat_info *info);
565enum read_header read_header (bool raw_extended_headers);
566enum read_header tar_checksum (union block *header, bool silent);
567void skip_file (off_t size);
568void skip_member (void);
569
570/* Module misc.c.  */
571
572void assign_string (char **dest, const char *src);
573char *quote_copy_string (const char *str);
574int unquote_string (char *str);
575
576void code_ns_fraction (int ns, char *p);
577char const *code_timespec (struct timespec ts, char *sbuf);
578enum { BILLION = 1000000000, LOG10_BILLION = 9 };
579enum { TIMESPEC_STRSIZE_BOUND =
580         UINTMAX_STRSIZE_BOUND + LOG10_BILLION + sizeof "-." - 1 };
581
582enum remove_option
583{
584  ORDINARY_REMOVE_OPTION,
585  RECURSIVE_REMOVE_OPTION,
586
587  /* FIXME: The following value is never used. It seems to be intended
588     as a placeholder for a hypothetical option that should instruct tar
589     to recursively remove subdirectories in purge_directory(),
590     as opposed to the functionality of --recursive-unlink
591     (RECURSIVE_REMOVE_OPTION value), which removes them in
592     prepare_to_extract() phase. However, with the addition of more
593     meta-info to the incremental dumps, this should become unnecessary */
594  WANT_DIRECTORY_REMOVE_OPTION
595};
596int remove_any_file (const char *file_name, enum remove_option option);
597bool maybe_backup_file (const char *file_name, bool this_is_the_archive);
598void undo_last_backup (void);
599
600int deref_stat (bool deref, char const *name, struct stat *buf);
601
602int chdir_arg (char const *dir);
603void chdir_do (int dir);
604
605void close_diag (char const *name);
606void open_diag (char const *name);
607void read_diag_details (char const *name, off_t offset, size_t size);
608void readlink_diag (char const *name);
609void savedir_diag (char const *name);
610void seek_diag_details (char const *name, off_t offset);
611void stat_diag (char const *name);
612void write_error_details (char const *name, size_t status, size_t size);
613void write_fatal (char const *name) __attribute__ ((noreturn));
614void write_fatal_details (char const *name, ssize_t status, size_t size)
615     __attribute__ ((noreturn));
616
617pid_t xfork (void);
618void xpipe (int fd[2]);
619
620void *page_aligned_alloc (void **ptr, size_t size);
621int set_file_atime (int fd, char const *file,
622		    struct timespec const timespec[2]);
623
624/* Module names.c.  */
625
626extern struct name *gnu_list_name;
627
628void gid_to_gname (gid_t gid, char **gname);
629int gname_to_gid (char const *gname, gid_t *pgid);
630void uid_to_uname (uid_t uid, char **uname);
631int uname_to_uid (char const *uname, uid_t *puid);
632
633void name_init (void);
634void name_add_name (const char *name, int matching_flags);
635void name_add_dir (const char *name);
636void name_term (void);
637const char *name_next (int change_dirs);
638void name_gather (void);
639struct name *addname (char const *string, int change_dir);
640bool name_match (const char *name);
641void names_notfound (void);
642void collect_and_sort_names (void);
643struct name *name_scan (const char *name);
644char *name_from_list (void);
645void blank_name_list (void);
646char *new_name (const char *dir_name, const char *name);
647size_t stripped_prefix_len (char const *file_name, size_t num);
648bool all_names_found (struct tar_stat_info *st);
649
650bool excluded_name (char const *name);
651
652void add_avoided_name (char const *name);
653bool is_avoided_name (char const *name);
654bool is_individual_file (char const *name);
655
656bool contains_dot_dot (char const *name);
657
658#define ISFOUND(c) ((occurrence_option == 0) ? (c)->found_count : \
659                    (c)->found_count == occurrence_option)
660#define WASFOUND(c) ((occurrence_option == 0) ? (c)->found_count : \
661                     (c)->found_count >= occurrence_option)
662
663/* Module tar.c.  */
664
665void usage (int);
666
667int confirm (const char *message_action, const char *name);
668void request_stdin (const char *option);
669
670void tar_stat_init (struct tar_stat_info *st);
671void tar_stat_destroy (struct tar_stat_info *st);
672void usage (int) __attribute__ ((noreturn));
673int tar_timespec_cmp (struct timespec a, struct timespec b);
674const char *archive_format_string (enum archive_format fmt);
675const char *subcommand_string (enum subcommand c);
676
677/* Module update.c.  */
678
679extern char *output_start;
680
681void update_archive (void);
682
683/* Module xheader.c.  */
684
685void xheader_init (struct xheader *xhdr);
686void xheader_decode (struct tar_stat_info *stat);
687void xheader_decode_global (struct xheader *xhdr);
688void xheader_store (char const *keyword, struct tar_stat_info *st,
689		    void const *data);
690void xheader_read (struct xheader *xhdr, union block *header, size_t size);
691void xheader_write (char type, char *name, struct xheader *xhdr);
692void xheader_write_global (struct xheader *xhdr);
693void xheader_finish (struct xheader *hdr);
694void xheader_destroy (struct xheader *hdr);
695char *xheader_xhdr_name (struct tar_stat_info *st);
696char *xheader_ghdr_name (void);
697void xheader_set_option (char *string);
698void xheader_string_begin (struct xheader *xhdr);
699void xheader_string_add (struct xheader *xhdr, char const *s);
700bool xheader_string_end (struct xheader *xhdr, char const *keyword);
701bool xheader_keyword_deleted_p (const char *kw);
702char *xheader_format_name (struct tar_stat_info *st, const char *fmt,
703			   size_t n);
704
705/* Module system.c */
706
707void sys_detect_dev_null_output (void);
708void sys_save_archive_dev_ino (void);
709void sys_drain_input_pipe (void);
710void sys_wait_for_child (pid_t);
711void sys_spawn_shell (void);
712bool sys_compare_uid (struct stat *a, struct stat *b);
713bool sys_compare_gid (struct stat *a, struct stat *b);
714bool sys_file_is_archive (struct tar_stat_info *p);
715bool sys_compare_links (struct stat *link_data, struct stat *stat_data);
716int sys_truncate (int fd);
717pid_t sys_child_open_for_compress (void);
718pid_t sys_child_open_for_uncompress (void);
719size_t sys_write_archive_buffer (void);
720bool sys_get_archive_stat (void);
721int sys_exec_command (char *file_name, int typechar, struct tar_stat_info *st);
722void sys_wait_command (void);
723int sys_exec_info_script (const char **archive_name, int volume_number);
724
725/* Module compare.c */
726void report_difference (struct tar_stat_info *st, const char *message, ...);
727
728/* Module sparse.c */
729bool sparse_member_p (struct tar_stat_info *st);
730bool sparse_fixup_header (struct tar_stat_info *st);
731enum dump_status sparse_dump_file (int, struct tar_stat_info *st);
732enum dump_status sparse_extract_file (int fd, struct tar_stat_info *st,
733				      off_t *size);
734enum dump_status sparse_skip_file (struct tar_stat_info *st);
735bool sparse_diff_file (int, struct tar_stat_info *st);
736
737/* Module utf8.c */
738bool string_ascii_p (const char *str);
739bool utf8_convert (bool to_utf, char const *input, char **output);
740
741/* Module transform.c */
742typedef enum
743  {
744    xform_regfile,
745    xform_link,
746    xform_symlink
747  } xform_type;
748
749void set_transform_expr (const char *expr);
750bool transform_name (char **pinput);
751bool transform_member_name (char **pinput, xform_type type);
752bool transform_name_fp (char **pinput, char *(*fun)(char *, void *), void *);
753