Dogcows Code - chaz/tar/blob - src/common.h

   1 /* Common declarations for the tar program.
   2
   3    Copyright 1988, 1992-1994, 1996-1997, 1999-2010, 2012-2015 Free
   4    Software Foundation, Inc.
   5
   6    This file is part of GNU tar.
   7
   8    GNU tar is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    GNU tar is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 /* Declare the GNU tar archive format.  */
  22 #include "tar.h"
  23
  24 /* The checksum field is filled with this while the checksum is computed.  */
  25 #define CHKBLANKS       "        "      /* 8 blanks, no null */
  26
  27 /* Some constants from POSIX are given names.  */
  28 #define NAME_FIELD_SIZE   100
  29 #define PREFIX_FIELD_SIZE 155
  30 #define UNAME_FIELD_SIZE   32
  31 #define GNAME_FIELD_SIZE   32
  32
  33
  34 \f
  35 /* Some various global definitions.  */
  36
  37 /* Name of file to use for interacting with user.  */
  38
  39 /* GLOBAL is defined to empty in tar.c only, and left alone in other *.c
  40    modules.  Here, we merely set it to "extern" if it is not already set.
  41    GNU tar does depend on the system loader to preset all GLOBAL variables to
  42    neutral (or zero) values, explicit initialization is usually not done.  */
  43 #ifndef GLOBAL
  44 # define GLOBAL extern
  45 #endif
  46
  47 #define TAREXIT_SUCCESS PAXEXIT_SUCCESS
  48 #define TAREXIT_DIFFERS PAXEXIT_DIFFERS
  49 #define TAREXIT_FAILURE PAXEXIT_FAILURE
  50
  51 \f
  52 #include "arith.h"
  53 #include <backupfile.h>
  54 #include <exclude.h>
  55 #include <full-write.h>
  56 #include <modechange.h>
  57 #include <quote.h>
  58 #include <safe-read.h>
  59 #include <stat-time.h>
  60 #include <timespec.h>
  61 #define obstack_chunk_alloc xmalloc
  62 #define obstack_chunk_free free
  63 #include <obstack.h>
  64 #include <progname.h>
  65 #include <xvasprintf.h>
  66
  67 #include <paxlib.h>
  68
  69 /* Log base 2 of common values.  */
  70 #define LG_8 3
  71 #define LG_64 6
  72 #define LG_256 8
  73
  74 _GL_INLINE_HEADER_BEGIN
  75 #ifndef COMMON_INLINE
  76 # define COMMON_INLINE _GL_INLINE
  77 #endif
  78 \f
  79 /* Information gleaned from the command line.  */
  80
  81 /* Main command option.  */
  82
  83 enum subcommand
  84 {
  85   UNKNOWN_SUBCOMMAND,           /* none of the following */
  86   APPEND_SUBCOMMAND,            /* -r */
  87   CAT_SUBCOMMAND,               /* -A */
  88   CREATE_SUBCOMMAND,            /* -c */
  89   DELETE_SUBCOMMAND,            /* -D */
  90   DIFF_SUBCOMMAND,              /* -d */
  91   EXTRACT_SUBCOMMAND,           /* -x */
  92   LIST_SUBCOMMAND,              /* -t */
  93   UPDATE_SUBCOMMAND,            /* -u */
  94   TEST_LABEL_SUBCOMMAND,        /* --test-label */
  95 };
  96
  97 GLOBAL enum subcommand subcommand_option;
  98
  99 /* Selected format for output archive.  */
 100 GLOBAL enum archive_format archive_format;
 101
 102 /* Size of each record, once in blocks, once in bytes.  Those two variables
 103    are always related, the second being BLOCKSIZE times the first.  They do
 104    not have _option in their name, even if their values is derived from
 105    option decoding, as these are especially important in tar.  */
 106 GLOBAL int blocking_factor;
 107 GLOBAL size_t record_size;
 108
 109 GLOBAL bool absolute_names_option;
 110
 111 /* Display file times in UTC */
 112 GLOBAL bool utc_option;
 113 /* Output file timestamps to the full resolution */
 114 GLOBAL bool full_time_option;
 115
 116 /* This variable tells how to interpret newer_mtime_option, below.  If zero,
 117    files get archived if their mtime is not less than newer_mtime_option.
 118    If nonzero, files get archived if *either* their ctime or mtime is not less
 119    than newer_mtime_option.  */
 120 GLOBAL int after_date_option;
 121
 122 enum atime_preserve
 123 {
 124   no_atime_preserve,
 125   replace_atime_preserve,
 126   system_atime_preserve
 127 };
 128 GLOBAL enum atime_preserve atime_preserve_option;
 129
 130 GLOBAL bool backup_option;
 131
 132 /* Type of backups being made.  */
 133 GLOBAL enum backup_type backup_type;
 134
 135 GLOBAL bool block_number_option;
 136
 137 GLOBAL unsigned checkpoint_option;
 138 #define DEFAULT_CHECKPOINT 10
 139
 140 /* Specified name of compression program, or "gzip" as implied by -z.  */
 141 GLOBAL const char *use_compress_program_option;
 142
 143 GLOBAL bool dereference_option;
 144 GLOBAL bool hard_dereference_option;
 145
 146 /* Patterns that match file names to be excluded.  */
 147 GLOBAL struct exclude *excluded;
 148
 149 enum exclusion_tag_type
 150   {
 151     exclusion_tag_none,
 152      /* Exclude the directory contents, but preserve the directory
 153         itself and the exclusion tag file */
 154     exclusion_tag_contents,
 155     /* Exclude everything below the directory, preserving the directory
 156        itself */
 157     exclusion_tag_under,
 158     /* Exclude entire directory  */
 159     exclusion_tag_all,
 160   };
 161
 162 /* Specified value to be put into tar file in place of stat () results, or
 163    just null and -1 if such an override should not take place.  */
 164 GLOBAL char const *group_name_option;
 165 GLOBAL gid_t group_option;
 166
 167 GLOBAL bool ignore_failed_read_option;
 168
 169 GLOBAL bool ignore_zeros_option;
 170
 171 GLOBAL bool incremental_option;
 172
 173 /* Specified name of script to run at end of each tape change.  */
 174 GLOBAL const char *info_script_option;
 175
 176 GLOBAL bool interactive_option;
 177
 178 /* If nonzero, extract only Nth occurrence of each named file */
 179 GLOBAL uintmax_t occurrence_option;
 180
 181 enum old_files
 182 {
 183   DEFAULT_OLD_FILES,          /* default */
 184   NO_OVERWRITE_DIR_OLD_FILES, /* --no-overwrite-dir */
 185   OVERWRITE_OLD_FILES,        /* --overwrite */
 186   UNLINK_FIRST_OLD_FILES,     /* --unlink-first */
 187   KEEP_OLD_FILES,             /* --keep-old-files */
 188   SKIP_OLD_FILES,             /* --skip-old-files */
 189   KEEP_NEWER_FILES            /* --keep-newer-files */
 190 };
 191 GLOBAL enum old_files old_files_option;
 192
 193 GLOBAL bool keep_directory_symlink_option;
 194
 195 /* Specified file name for incremental list.  */
 196 GLOBAL const char *listed_incremental_option;
 197 /* Incremental dump level */
 198 GLOBAL int incremental_level;
 199 /* Check device numbers when doing incremental dumps. */
 200 GLOBAL bool check_device_option;
 201
 202 /* Specified mode change string.  */
 203 GLOBAL struct mode_change *mode_option;
 204
 205 /* Initial umask, if needed for mode change string.  */
 206 GLOBAL mode_t initial_umask;
 207
 208 GLOBAL bool multi_volume_option;
 209
 210 /* Specified threshold date and time.  Files having an older time stamp
 211    do not get archived (also see after_date_option above).  */
 212 GLOBAL struct timespec newer_mtime_option;
 213
 214 /* If true, override actual mtime (see below) */
 215 GLOBAL bool set_mtime_option;
 216 /* Value to be put in mtime header field instead of the actual mtime */
 217 GLOBAL struct timespec mtime_option;
 218
 219 /* Return true if newer_mtime_option is initialized.  */
 220 #define NEWER_OPTION_INITIALIZED(opt) (0 <= (opt).tv_nsec)
 221
 222 /* Return true if the struct stat ST's M time is less than
 223    newer_mtime_option.  */
 224 #define OLDER_STAT_TIME(st, m) \
 225   (timespec_cmp (get_stat_##m##time (&(st)), newer_mtime_option) < 0)
 226
 227 /* Likewise, for struct tar_stat_info ST.  */
 228 #define OLDER_TAR_STAT_TIME(st, m) \
 229   (timespec_cmp ((st).m##time, newer_mtime_option) < 0)
 230
 231 /* Zero if there is no recursion, otherwise FNM_LEADING_DIR.  */
 232 GLOBAL int recursion_option;
 233
 234 GLOBAL bool numeric_owner_option;
 235
 236 GLOBAL bool one_file_system_option;
 237
 238 /* Create a top-level directory for extracting based on the archive name.  */
 239 GLOBAL bool one_top_level_option;
 240 GLOBAL char *one_top_level_dir;
 241
 242 /* Specified value to be put into tar file in place of stat () results, or
 243    just null and -1 if such an override should not take place.  */
 244 GLOBAL char const *owner_name_option;
 245 GLOBAL uid_t owner_option;
 246
 247 GLOBAL bool recursive_unlink_option;
 248
 249 GLOBAL bool read_full_records_option;
 250
 251 GLOBAL bool remove_files_option;
 252
 253 /* Specified remote shell command.  */
 254 GLOBAL const char *rsh_command_option;
 255
 256 GLOBAL bool same_order_option;
 257
 258 /* If positive, preserve ownership when extracting.  */
 259 GLOBAL int same_owner_option;
 260
 261 /* If positive, preserve permissions when extracting.  */
 262 GLOBAL int same_permissions_option;
 263
 264 /* If positive, save the SELinux context.  */
 265 GLOBAL int selinux_context_option;
 266
 267 /* If positive, save the ACLs.  */
 268 GLOBAL int acls_option;
 269
 270 /* If positive, save the user and root xattrs.  */
 271 GLOBAL int xattrs_option;
 272
 273 /* When set, strip the given number of file name components from the file name
 274    before extracting */
 275 GLOBAL size_t strip_name_components;
 276
 277 GLOBAL bool show_omitted_dirs_option;
 278
 279 GLOBAL bool sparse_option;
 280 GLOBAL unsigned tar_sparse_major;
 281 GLOBAL unsigned tar_sparse_minor;
 282
 283 GLOBAL bool starting_file_option;
 284
 285 /* Specified maximum byte length of each tape volume (multiple of 1024).  */
 286 GLOBAL tarlong tape_length_option;
 287
 288 GLOBAL bool to_stdout_option;
 289
 290 GLOBAL bool totals_option;
 291
 292 GLOBAL bool touch_option;
 293
 294 GLOBAL char *to_command_option;
 295 GLOBAL bool ignore_command_error_option;
 296
 297 /* Restrict some potentially harmful tar options */
 298 GLOBAL bool restrict_option;
 299
 300 /* Return true if the extracted files are not being written to disk */
 301 #define EXTRACT_OVER_PIPE (to_stdout_option || to_command_option)
 302
 303 /* Count how many times the option has been set, multiple setting yields
 304    more verbose behavior.  Value 0 means no verbosity, 1 means file name
 305    only, 2 means file name and all attributes.  More than 2 is just like 2.  */
 306 GLOBAL int verbose_option;
 307
 308 GLOBAL bool verify_option;
 309
 310 /* Specified name of file containing the volume number.  */
 311 GLOBAL const char *volno_file_option;
 312
 313 /* Specified value or pattern.  */
 314 GLOBAL const char *volume_label_option;
 315 \f
 316 /* Other global variables.  */
 317
 318 /* File descriptor for archive file.  */
 319 GLOBAL int archive;
 320
 321 /* Nonzero when outputting to /dev/null.  */
 322 GLOBAL bool dev_null_output;
 323
 324 /* Timestamps: */
 325 GLOBAL struct timespec start_time;        /* when we started execution */
 326 GLOBAL struct timespec volume_start_time; /* when the current volume was
 327                                              opened*/
 328 GLOBAL struct timespec last_stat_time;    /* when the statistics was last
 329                                              computed */
 330
 331 GLOBAL struct tar_stat_info current_stat_info;
 332
 333 /* List of tape drive names, number of such tape drives,
 334    and current cursor in list.  */
 335 GLOBAL const char **archive_name_array;
 336 GLOBAL size_t archive_names;
 337 GLOBAL const char **archive_name_cursor;
 338
 339 /* Output index file name.  */
 340 GLOBAL char const *index_file_name;
 341
 342 /* Opaque structure for keeping directory meta-data */
 343 struct directory;
 344
 345 /* Structure for keeping track of filenames and lists thereof.  */
 346 struct name
 347   {
 348     struct name *next;          /* Link to the next element */
 349     struct name *prev;          /* Link to the previous element */
 350
 351     char *name;                 /* File name or globbing pattern */
 352     size_t length;              /* cached strlen (name) */
 353     int matching_flags;         /* wildcard flags if name is a pattern */
 354     bool cmdline;               /* true if this name was given in the
 355                                    command line */
 356
 357     int change_dir;             /* Number of the directory to change to.
 358                                    Set with the -C option. */
 359     uintmax_t found_count;      /* number of times a matching file has
 360                                    been found */
 361
 362     /* The following members are used for incremental dumps only,
 363        if this struct name represents a directory;
 364        see incremen.c */
 365     struct directory *directory;/* directory meta-data and contents */
 366     struct name *parent;        /* pointer to the parent hierarchy */
 367     struct name *child;         /* pointer to the first child */
 368     struct name *sibling;       /* pointer to the next sibling */
 369     char *caname;               /* canonical name */
 370   };
 371
 372 /* Obnoxious test to see if dimwit is trying to dump the archive.  */
 373 GLOBAL dev_t ar_dev;
 374 GLOBAL ino_t ar_ino;
 375
 376 /* Flags for reading, searching, and fstatatting files.  */
 377 GLOBAL int open_read_flags;
 378 GLOBAL int open_searchdir_flags;
 379 GLOBAL int fstatat_flags;
 380
 381 GLOBAL int seek_option;
 382 GLOBAL bool seekable_archive;
 383
 384 GLOBAL dev_t root_device;
 385
 386 /* Unquote filenames */
 387 GLOBAL bool unquote_option;
 388
 389 /* Treat file names read from -T input verbatim */
 390 GLOBAL bool verbatim_files_from_option;
 391
 392 GLOBAL int savedir_sort_order;
 393
 394 /* Show file or archive names after transformation.
 395    In particular, when creating archive in verbose mode, list member names
 396    as stored in the archive */
 397 GLOBAL bool show_transformed_names_option;
 398
 399 /* Delay setting modification times and permissions of extracted directories
 400    until the end of extraction. This variable helps correctly restore directory
 401    timestamps from archives with an unusual member order. It is automatically
 402    set for incremental archives. */
 403 GLOBAL bool delay_directory_restore_option;
 404
 405 /* Warn about implicit use of the wildcards in command line arguments.
 406    (Default for tar prior to 1.15.91, but changed afterwards */
 407 GLOBAL bool warn_regex_usage;
 408 \f
 409 /* Declarations for each module.  */
 410
 411 /* FIXME: compare.c should not directly handle the following variable,
 412    instead, this should be done in buffer.c only.  */
 413
 414 enum access_mode
 415 {
 416   ACCESS_READ,
 417   ACCESS_WRITE,
 418   ACCESS_UPDATE
 419 };
 420 extern enum access_mode access_mode;
 421
 422 /* Module buffer.c.  */
 423
 424 extern FILE *stdlis;
 425 extern bool write_archive_to_stdout;
 426 extern char *volume_label;
 427 extern size_t volume_label_count;
 428 extern char *continued_file_name;
 429 extern uintmax_t continued_file_size;
 430 extern uintmax_t continued_file_offset;
 431 extern off_t records_written;
 432
 433 char *drop_volume_label_suffix (const char *label);
 434
 435 size_t available_space_after (union block *pointer);
 436 off_t current_block_ordinal (void);
 437 void close_archive (void);
 438 void closeout_volume_number (void);
 439 double compute_duration (void);
 440 union block *find_next_block (void);
 441 void flush_read (void);
 442 void flush_write (void);
 443 void flush_archive (void);
 444 void init_volume_number (void);
 445 void open_archive (enum access_mode mode);
 446 void print_total_stats (void);
 447 void reset_eof (void);
 448 void set_next_block_after (union block *block);
 449 void clear_read_error_count (void);
 450 void xclose (int fd);
 451 void archive_write_error (ssize_t status) __attribute__ ((noreturn));
 452 void archive_read_error (void);
 453 off_t seek_archive (off_t size);
 454 void set_start_time (void);
 455
 456 #define TF_READ    0
 457 #define TF_WRITE   1
 458 #define TF_DELETED 2
 459 int format_total_stats (FILE *fp, const char **formats, int eor, int eol);
 460 void print_total_stats (void);
 461
 462 void mv_begin_write (const char *file_name, off_t totsize, off_t sizeleft);
 463
 464 void mv_begin_read (struct tar_stat_info *st);
 465 void mv_end (void);
 466 void mv_size_left (off_t size);
 467
 468 void buffer_write_global_xheader (void);
 469
 470 const char *first_decompress_program (int *pstate);
 471 const char *next_decompress_program (int *pstate);
 472
 473 /* Module create.c.  */
 474
 475 enum dump_status
 476   {
 477     dump_status_ok,
 478     dump_status_short,
 479     dump_status_fail,
 480     dump_status_not_implemented
 481   };
 482
 483 void add_exclusion_tag (const char *name, enum exclusion_tag_type type,
 484                         bool (*predicate) (int));
 485 bool cachedir_file_p (int fd);
 486 char *get_directory_entries (struct tar_stat_info *st);
 487
 488 void create_archive (void);
 489 void pad_archive (off_t size_left);
 490 void dump_file (struct tar_stat_info *parent, char const *name,
 491                 char const *fullname);
 492 union block *start_header (struct tar_stat_info *st);
 493 void finish_header (struct tar_stat_info *st, union block *header,
 494                     off_t block_ordinal);
 495 void simple_finish_header (union block *header);
 496 union block * write_extended (bool global, struct tar_stat_info *st,
 497                               union block *old_header);
 498 union block *start_private_header (const char *name, size_t size, time_t t);
 499 void write_eot (void);
 500 void check_links (void);
 501 int subfile_open (struct tar_stat_info const *dir, char const *file, int flags);
 502 void restore_parent_fd (struct tar_stat_info const *st);
 503 void exclusion_tag_warning (const char *dirname, const char *tagname,
 504                             const char *message);
 505 enum exclusion_tag_type check_exclusion_tags (struct tar_stat_info const *st,
 506                                               const char **tag_file_name);
 507
 508 #define OFF_TO_CHARS(val, where) off_to_chars (val, where, sizeof (where))
 509 #define TIME_TO_CHARS(val, where) time_to_chars (val, where, sizeof (where))
 510
 511 bool off_to_chars (off_t off, char *buf, size_t size);
 512 bool time_to_chars (time_t t, char *buf, size_t size);
 513
 514 /* Module diffarch.c.  */
 515
 516 extern bool now_verifying;
 517
 518 void diff_archive (void);
 519 void diff_init (void);
 520 void verify_volume (void);
 521
 522 /* Module extract.c.  */
 523
 524 void extr_init (void);
 525 void extract_archive (void);
 526 void extract_finish (void);
 527 bool rename_directory (char *src, char *dst);
 528
 529 void remove_delayed_set_stat (const char *fname);
 530
 531 /* Module delete.c.  */
 532
 533 void delete_archive_members (void);
 534
 535 /* Module incremen.c.  */
 536
 537 struct directory *scan_directory (struct tar_stat_info *st);
 538 const char *directory_contents (struct directory *dir);
 539 const char *safe_directory_contents (struct directory *dir);
 540
 541 void rebase_directory (struct directory *dir,
 542                        const char *samp, size_t slen,
 543                        const char *repl, size_t rlen);
 544
 545 void append_incremental_renames (struct directory *dir);
 546 void show_snapshot_field_ranges (void);
 547 void read_directory_file (void);
 548 void write_directory_file (void);
 549 void purge_directory (char const *directory_name);
 550 void list_dumpdir (char *buffer, size_t size);
 551 void update_parent_directory (struct tar_stat_info *st);
 552
 553 size_t dumpdir_size (const char *p);
 554 bool is_dumpdir (struct tar_stat_info *stat_info);
 555 void clear_directory_table (void);
 556
 557 /* Module list.c.  */
 558
 559 enum read_header
 560 {
 561   HEADER_STILL_UNREAD,          /* for when read_header has not been called */
 562   HEADER_SUCCESS,               /* header successfully read and checksummed */
 563   HEADER_SUCCESS_EXTENDED,      /* likewise, but we got an extended header */
 564   HEADER_ZERO_BLOCK,            /* zero block where header expected */
 565   HEADER_END_OF_FILE,           /* true end of file while header expected */
 566   HEADER_FAILURE                /* ill-formed header, or bad checksum */
 567 };
 568
 569 /* Operation mode for read_header: */
 570
 571 enum read_header_mode
 572 {
 573   read_header_auto,             /* process extended headers automatically */
 574   read_header_x_raw,            /* return raw extended headers (return
 575                                    HEADER_SUCCESS_EXTENDED) */
 576   read_header_x_global          /* when POSIX global extended header is read,
 577                                    decode it and return
 578                                    HEADER_SUCCESS_EXTENDED */
 579 };
 580 extern union block *current_header;
 581 extern enum archive_format current_format;
 582 extern size_t recent_long_name_blocks;
 583 extern size_t recent_long_link_blocks;
 584
 585 void decode_header (union block *header, struct tar_stat_info *stat_info,
 586                     enum archive_format *format_pointer, int do_user_group);
 587 void transform_stat_info (int typeflag, struct tar_stat_info *stat_info);
 588 char const *tartime (struct timespec t, bool full_time);
 589
 590 #define OFF_FROM_HEADER(where) off_from_header (where, sizeof (where))
 591 #define UINTMAX_FROM_HEADER(where) uintmax_from_header (where, sizeof (where))
 592
 593 off_t off_from_header (const char *buf, size_t size);
 594 uintmax_t uintmax_from_header (const char *buf, size_t size);
 595
 596 void list_archive (void);
 597 void test_archive_label (void);
 598 void print_for_mkdir (char *dirname, int length, mode_t mode);
 599 void print_header (struct tar_stat_info *st, union block *blk,
 600                    off_t block_ordinal);
 601 void read_and (void (*do_something) (void));
 602 enum read_header read_header (union block **return_block,
 603                               struct tar_stat_info *info,
 604                               enum read_header_mode m);
 605 enum read_header tar_checksum (union block *header, bool silent);
 606 void skip_file (off_t size);
 607 void skip_member (void);
 608
 609 /* Module misc.c.  */
 610
 611 #define min(a, b) ((a) < (b) ? (a) : (b))
 612 #define max(a, b) ((a) < (b) ? (b) : (a))
 613 void assign_string (char **dest, const char *src);
 614 int unquote_string (char *str);
 615 char *zap_slashes (char *name);
 616 char *normalize_filename (int cdidx, const char *name);
 617 void normalize_filename_x (char *name);
 618 void replace_prefix (char **pname, const char *samp, size_t slen,
 619                      const char *repl, size_t rlen);
 620 char *tar_savedir (const char *name, int must_exist);
 621
 622 typedef struct namebuf *namebuf_t;
 623 namebuf_t namebuf_create (const char *dir);
 624 void namebuf_free (namebuf_t buf);
 625 char *namebuf_name (namebuf_t buf, const char *name);
 626 void namebuf_add_dir (namebuf_t buf, const char *name);
 627 char *namebuf_finish (namebuf_t buf);
 628
 629 const char *tar_dirname (void);
 630
 631 /* Represent N using a signed integer I such that (uintmax_t) I == N.
 632    With a good optimizing compiler, this is equivalent to (intmax_t) i
 633    and requires zero machine instructions.  */
 634 #if ! (UINTMAX_MAX / 2 <= INTMAX_MAX)
 635 # error "represent_uintmax returns intmax_t to represent uintmax_t"
 636 #endif
 637 COMMON_INLINE intmax_t
 638 represent_uintmax (uintmax_t n)
 639 {
 640   if (n <= INTMAX_MAX)
 641     return n;
 642   else
 643     {
 644       /* Avoid signed integer overflow on picky platforms.  */
 645       intmax_t nd = n - INTMAX_MIN;
 646       return nd + INTMAX_MIN;
 647     }
 648 }
 649
 650 enum { SYSINT_BUFSIZE =
 651          max (UINTMAX_STRSIZE_BOUND, INT_BUFSIZE_BOUND (intmax_t)) };
 652 char *sysinttostr (uintmax_t, intmax_t, uintmax_t, char buf[SYSINT_BUFSIZE]);
 653 intmax_t strtosysint (char const *, char **, intmax_t, uintmax_t);
 654 void code_ns_fraction (int ns, char *p);
 655 char const *code_timespec (struct timespec ts, char *sbuf);
 656 enum { BILLION = 1000000000, LOG10_BILLION = 9 };
 657 enum { TIMESPEC_STRSIZE_BOUND =
 658          UINTMAX_STRSIZE_BOUND + LOG10_BILLION + sizeof "-." - 1 };
 659 struct timespec decode_timespec (char const *, char **, bool);
 660
 661 /* Return true if T does not represent an out-of-range or invalid value.  */
 662 COMMON_INLINE bool
 663 valid_timespec (struct timespec t)
 664 {
 665   return 0 <= t.tv_nsec;
 666 }
 667
 668 bool must_be_dot_or_slash (char const *);
 669
 670 enum remove_option
 671 {
 672   ORDINARY_REMOVE_OPTION,
 673   RECURSIVE_REMOVE_OPTION,
 674
 675   /* FIXME: The following value is never used. It seems to be intended
 676      as a placeholder for a hypothetical option that should instruct tar
 677      to recursively remove subdirectories in purge_directory(),
 678      as opposed to the functionality of --recursive-unlink
 679      (RECURSIVE_REMOVE_OPTION value), which removes them in
 680      prepare_to_extract() phase. However, with the addition of more
 681      meta-info to the incremental dumps, this should become unnecessary */
 682   WANT_DIRECTORY_REMOVE_OPTION
 683 };
 684 int remove_any_file (const char *file_name, enum remove_option option);
 685 bool maybe_backup_file (const char *file_name, bool this_is_the_archive);
 686 void undo_last_backup (void);
 687
 688 int deref_stat (char const *name, struct stat *buf);
 689
 690 size_t blocking_read (int fd, void *buf, size_t count);
 691 size_t blocking_write (int fd, void const *buf, size_t count);
 692
 693 extern int chdir_current;
 694 extern int chdir_fd;
 695 int chdir_arg (char const *dir);
 696 void chdir_do (int dir);
 697 int chdir_count (void);
 698
 699 void close_diag (char const *name);
 700 void open_diag (char const *name);
 701 void read_diag_details (char const *name, off_t offset, size_t size);
 702 void readlink_diag (char const *name);
 703 void savedir_diag (char const *name);
 704 void seek_diag_details (char const *name, off_t offset);
 705 void stat_diag (char const *name);
 706 void file_removed_diag (const char *name, bool top_level,
 707                         void (*diagfn) (char const *name));
 708 void write_error_details (char const *name, size_t status, size_t size);
 709 void write_fatal (char const *name) __attribute__ ((noreturn));
 710 void write_fatal_details (char const *name, ssize_t status, size_t size)
 711      __attribute__ ((noreturn));
 712
 713 pid_t xfork (void);
 714 void xpipe (int fd[2]);
 715
 716 void *page_aligned_alloc (void **ptr, size_t size);
 717 int set_file_atime (int fd, int parentfd, char const *file,
 718                     struct timespec atime);
 719
 720 /* Module names.c.  */
 721
 722 extern size_t name_count;
 723 extern struct name *gnu_list_name;
 724
 725 void gid_to_gname (gid_t gid, char **gname);
 726 int gname_to_gid (char const *gname, gid_t *pgid);
 727 void uid_to_uname (uid_t uid, char **uname);
 728 int uname_to_uid (char const *uname, uid_t *puid);
 729
 730 void name_init (void);
 731 void name_add_name (const char *name, int matching_flags);
 732 void name_add_dir (const char *name);
 733 void name_add_file (const char *name, int term, bool verbatim,
 734                     int matching_flags);
 735 void name_term (void);
 736 const char *name_next (int change_dirs);
 737 void name_gather (void);
 738 struct name *addname (char const *string, int change_dir,
 739                       bool cmdline, struct name *parent);
 740 void remname (struct name *name);
 741 bool name_match (const char *name);
 742 void names_notfound (void);
 743 void label_notfound (void);
 744 void collect_and_sort_names (void);
 745 struct name *name_scan (const char *name);
 746 struct name const *name_from_list (void);
 747 void blank_name_list (void);
 748 char *new_name (const char *dir_name, const char *name);
 749 size_t stripped_prefix_len (char const *file_name, size_t num);
 750 bool all_names_found (struct tar_stat_info *st);
 751
 752 void add_avoided_name (char const *name);
 753 bool is_avoided_name (char const *name);
 754
 755 bool contains_dot_dot (char const *name);
 756
 757 #define ISFOUND(c) (occurrence_option == 0                      \
 758                     ? (c)->found_count != 0                     \
 759                     : (c)->found_count == occurrence_option)
 760 #define WASFOUND(c) (occurrence_option == 0                     \
 761                      ? (c)->found_count != 0                    \
 762                      : (c)->found_count >= occurrence_option)
 763
 764 /* Module tar.c.  */
 765
 766 void usage (int);
 767
 768 int confirm (const char *message_action, const char *name);
 769
 770 void tar_stat_init (struct tar_stat_info *st);
 771 bool tar_stat_close (struct tar_stat_info *st);
 772 void tar_stat_destroy (struct tar_stat_info *st);
 773 void usage (int) __attribute__ ((noreturn));
 774 int tar_timespec_cmp (struct timespec a, struct timespec b);
 775 const char *archive_format_string (enum archive_format fmt);
 776 const char *subcommand_string (enum subcommand c);
 777 void set_exit_status (int val);
 778
 779 void request_stdin (const char *option);
 780 void more_options (int argc, char **argv);
 781
 782 /* Module update.c.  */
 783
 784 extern char *output_start;
 785
 786 void update_archive (void);
 787
 788 /* Module attrs.c.  */
 789 #include "xattrs.h"
 790
 791 /* Module xheader.c.  */
 792
 793 void xheader_decode (struct tar_stat_info *stat);
 794 void xheader_decode_global (struct xheader *xhdr);
 795 void xheader_store (char const *keyword, struct tar_stat_info *st,
 796                     void const *data);
 797 void xheader_read (struct xheader *xhdr, union block *header, off_t size);
 798 void xheader_write (char type, char *name, time_t t, struct xheader *xhdr);
 799 void xheader_write_global (struct xheader *xhdr);
 800 void xheader_finish (struct xheader *hdr);
 801 void xheader_destroy (struct xheader *hdr);
 802 char *xheader_xhdr_name (struct tar_stat_info *st);
 803 char *xheader_ghdr_name (void);
 804 void xheader_set_option (char *string);
 805 void xheader_string_begin (struct xheader *xhdr);
 806 void xheader_string_add (struct xheader *xhdr, char const *s);
 807 bool xheader_string_end (struct xheader *xhdr, char const *keyword);
 808 bool xheader_keyword_deleted_p (const char *kw);
 809 char *xheader_format_name (struct tar_stat_info *st, const char *fmt,
 810                            size_t n);
 811 void xheader_xattr_init (struct tar_stat_info *st);
 812 void xheader_xattr_free (struct xattr_array *vals, size_t sz);
 813 void xheader_xattr_copy (const struct tar_stat_info *st,
 814                          struct xattr_array **vals, size_t *sz);
 815 void xheader_xattr_add (struct tar_stat_info *st,
 816                         const char *key, const char *val, size_t len);
 817
 818 /* Module system.c */
 819
 820 void sys_detect_dev_null_output (void);
 821 void sys_save_archive_dev_ino (void);
 822 void sys_wait_for_child (pid_t, bool);
 823 void sys_spawn_shell (void);
 824 bool sys_compare_uid (struct stat *a, struct stat *b);
 825 bool sys_compare_gid (struct stat *a, struct stat *b);
 826 bool sys_file_is_archive (struct tar_stat_info *p);
 827 bool sys_compare_links (struct stat *link_data, struct stat *stat_data);
 828 int sys_truncate (int fd);
 829 pid_t sys_child_open_for_compress (void);
 830 pid_t sys_child_open_for_uncompress (void);
 831 size_t sys_write_archive_buffer (void);
 832 bool sys_get_archive_stat (void);
 833 int sys_exec_command (char *file_name, int typechar, struct tar_stat_info *st);
 834 void sys_wait_command (void);
 835 int sys_exec_info_script (const char **archive_name, int volume_number);
 836 void sys_exec_checkpoint_script (const char *script_name,
 837                                  const char *archive_name,
 838                                  int checkpoint_number);
 839
 840 /* Module compare.c */
 841 void report_difference (struct tar_stat_info *st, const char *message, ...)
 842   __attribute__ ((format (printf, 2, 3)));
 843
 844 /* Module sparse.c */
 845 bool sparse_member_p (struct tar_stat_info *st);
 846 bool sparse_fixup_header (struct tar_stat_info *st);
 847 enum dump_status sparse_dump_file (int, struct tar_stat_info *st);
 848 enum dump_status sparse_extract_file (int fd, struct tar_stat_info *st,
 849                                       off_t *size);
 850 enum dump_status sparse_skip_file (struct tar_stat_info *st);
 851 bool sparse_diff_file (int, struct tar_stat_info *st);
 852
 853 /* Module utf8.c */
 854 bool string_ascii_p (const char *str);
 855 bool utf8_convert (bool to_utf, char const *input, char **output);
 856
 857 /* Module transform.c */
 858 #define XFORM_REGFILE  0x01
 859 #define XFORM_LINK     0x02
 860 #define XFORM_SYMLINK  0x04
 861 #define XFORM_ALL      (XFORM_REGFILE|XFORM_LINK|XFORM_SYMLINK)
 862
 863 void set_transform_expr (const char *expr);
 864 bool transform_name (char **pinput, int type);
 865 bool transform_name_fp (char **pinput, int type,
 866                         char *(*fun)(char *, void *), void *);
 867 bool transform_program_p (void);
 868
 869 /* Module suffix.c */
 870 void set_compression_program_by_suffix (const char *name, const char *defprog);
 871 char *strip_compression_suffix (const char *name);
 872
 873 /* Module checkpoint.c */
 874 void checkpoint_compile_action (const char *str);
 875 void checkpoint_finish_compile (void);
 876 void checkpoint_run (bool do_write);
 877 void checkpoint_finish (void);
 878 void checkpoint_flush_actions (void);
 879
 880 /* Module warning.c */
 881 #define WARN_ALONE_ZERO_BLOCK    0x00000001
 882 #define WARN_BAD_DUMPDIR         0x00000002
 883 #define WARN_CACHEDIR            0x00000004
 884 #define WARN_CONTIGUOUS_CAST     0x00000008
 885 #define WARN_FILE_CHANGED        0x00000010
 886 #define WARN_FILE_IGNORED        0x00000020
 887 #define WARN_FILE_REMOVED        0x00000040
 888 #define WARN_FILE_SHRANK         0x00000080
 889 #define WARN_FILE_UNCHANGED      0x00000100
 890 #define WARN_FILENAME_WITH_NULS  0x00000200
 891 #define WARN_IGNORE_ARCHIVE      0x00000400
 892 #define WARN_IGNORE_NEWER        0x00000800
 893 #define WARN_NEW_DIRECTORY       0x00001000
 894 #define WARN_RENAME_DIRECTORY    0x00002000
 895 #define WARN_SYMLINK_CAST        0x00004000
 896 #define WARN_TIMESTAMP           0x00008000
 897 #define WARN_UNKNOWN_CAST        0x00010000
 898 #define WARN_UNKNOWN_KEYWORD     0x00020000
 899 #define WARN_XDEV                0x00040000
 900 #define WARN_DECOMPRESS_PROGRAM  0x00080000
 901 #define WARN_EXISTING_FILE       0x00100000
 902 #define WARN_XATTR_WRITE         0x00200000
 903 #define WARN_RECORD_SIZE         0x00400000
 904
 905 /* These warnings are enabled by default in verbose mode: */
 906 #define WARN_VERBOSE_WARNINGS    (WARN_RENAME_DIRECTORY|WARN_NEW_DIRECTORY|\
 907                                   WARN_DECOMPRESS_PROGRAM|WARN_EXISTING_FILE|\
 908                                   WARN_RECORD_SIZE)
 909 #define WARN_ALL                 (~WARN_VERBOSE_WARNINGS)
 910
 911 void set_warning_option (const char *arg);
 912
 913 extern int warning_option;
 914
 915 #define WARNOPT(opt,args)                       \
 916   do                                            \
 917     {                                           \
 918       if (warning_option & opt) WARN (args);    \
 919     }                                           \
 920   while (0)
 921
 922 /* Module unlink.c */
 923
 924 void queue_deferred_unlink (const char *name, bool is_dir);
 925 void finish_deferred_unlinks (void);
 926
 927 /* Module exit.c */
 928 extern void (*fatal_exit_hook) (void);
 929
 930 /* Module exclist.c */
 931 #define EXCL_DEFAULT       0x00
 932 #define EXCL_RECURSIVE     0x01
 933 #define EXCL_NON_RECURSIVE 0x02
 934
 935 void excfile_add (const char *name, int flags);
 936 void info_attach_exclist (struct tar_stat_info *dir);
 937 void info_cleanup_exclist (struct tar_stat_info *dir);
 938 void info_free_exclist (struct tar_stat_info *dir);
 939 bool excluded_name (char const *name, struct tar_stat_info *st);
 940 void exclude_vcs_ignores (void);
 941
 942 _GL_INLINE_HEADER_END