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