src/common.h

   1 /* Common declarations for the tar program.
   2
   3    Copyright 1988-2023 Free Software Foundation, Inc.
   4
   5    This file is part of GNU tar.
   6
   7    GNU tar is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    GNU tar is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 /* Declare the GNU tar archive format.  */
  21 #include "tar.h"
  22
  23 /* The checksum field is filled with this while the checksum is computed.  */
  24 #define CHKBLANKS       "        "      /* 8 blanks, no null */
  25
  26 /* Some constants from POSIX are given names.  */
  27 #define NAME_FIELD_SIZE   100
  28 #define PREFIX_FIELD_SIZE 155
  29 #define UNAME_FIELD_SIZE   32
  30 #define GNAME_FIELD_SIZE   32
  31
  32
  33 \f
  34 /* Some various global definitions.  */
  35
  36 /* Name of file to use for interacting with user.  */
  37
  38 /* GLOBAL is defined to empty in tar.c only, and left alone in other *.c
  39    modules.  Here, we merely set it to "extern" if it is not already set.
  40    GNU tar does depend on the system loader to preset all GLOBAL variables to
  41    neutral (or zero) values, explicit initialization is usually not done.  */
  42 #ifndef GLOBAL
  43 # define GLOBAL extern
  44 #endif
  45
  46 #define TAREXIT_SUCCESS PAXEXIT_SUCCESS
  47 #define TAREXIT_DIFFERS PAXEXIT_DIFFERS
  48 #define TAREXIT_FAILURE PAXEXIT_FAILURE
  49
  50 \f
  51 #include "arith.h"
  52 #include <attribute.h>
  53 #include <backupfile.h>
  54 #include <exclude.h>
  55 #include <full-write.h>
  56 #include <idx.h>
  57 #include <inttostr.h>
  58 #include <modechange.h>
  59 #include <quote.h>
  60 #include <safe-read.h>
  61 #include <full-read.h>
  62 #include <stat-time.h>
  63 #include <timespec.h>
  64 #define obstack_chunk_alloc xmalloc
  65 #define obstack_chunk_free free
  66 #include <obstack.h>
  67 #include <progname.h>
  68 #include <xvasprintf.h>
  69
  70 #include <paxlib.h>
  71
  72 /* Log base 2 of common values.  */
  73 #define LG_8 3
  74 #define LG_64 6
  75 #define LG_256 8
  76
  77 _GL_INLINE_HEADER_BEGIN
  78 #ifndef COMMON_INLINE
  79 # define COMMON_INLINE _GL_INLINE
  80 #endif
  81 \f
  82 /* Information gleaned from the command line.  */
  83
  84 /* Main command option.  */
  85
  86 enum subcommand
  87 {
  88   UNKNOWN_SUBCOMMAND,           /* none of the following */
  89   APPEND_SUBCOMMAND,            /* -r */
  90   CAT_SUBCOMMAND,               /* -A */
  91   CREATE_SUBCOMMAND,            /* -c */
  92   DELETE_SUBCOMMAND,            /* -D */
  93   DIFF_SUBCOMMAND,              /* -d */
  94   EXTRACT_SUBCOMMAND,           /* -x */
  95   LIST_SUBCOMMAND,              /* -t */
  96   UPDATE_SUBCOMMAND,            /* -u */
  97   TEST_LABEL_SUBCOMMAND,        /* --test-label */
  98 };
  99
 100 GLOBAL enum subcommand subcommand_option;
 101
 102 /* Selected format for output archive.  */
 103 GLOBAL enum archive_format archive_format;
 104
 105 /* Size of each record, once in blocks, once in bytes.  Those two variables
 106    are always related, the second being BLOCKSIZE times the first.  They do
 107    not have _option in their name, even if their values is derived from
 108    option decoding, as these are especially important in tar.  */
 109 GLOBAL int blocking_factor;
 110 GLOBAL size_t record_size;
 111
 112 GLOBAL bool absolute_names_option;
 113
 114 /* Display file times in UTC */
 115 GLOBAL bool utc_option;
 116 /* Output file timestamps to the full resolution */
 117 GLOBAL bool full_time_option;
 118
 119 /* This variable tells how to interpret newer_mtime_option, below.  If zero,
 120    files get archived if their mtime is not less than newer_mtime_option.
 121    If nonzero, files get archived if *either* their ctime or mtime is not less
 122    than newer_mtime_option.  */
 123 GLOBAL int after_date_option;
 124
 125 enum atime_preserve
 126 {
 127   no_atime_preserve,
 128   replace_atime_preserve,
 129   system_atime_preserve
 130 };
 131 GLOBAL enum atime_preserve atime_preserve_option;
 132
 133 GLOBAL bool backup_option;
 134
 135 /* Type of backups being made.  */
 136 GLOBAL enum backup_type backup_type;
 137
 138 GLOBAL bool block_number_option;
 139
 140 GLOBAL unsigned checkpoint_option;
 141 #define DEFAULT_CHECKPOINT 10
 142
 143 /* Specified name of compression program, or "gzip" as implied by -z.  */
 144 GLOBAL const char *use_compress_program_option;
 145
 146 GLOBAL bool dereference_option;
 147 GLOBAL bool hard_dereference_option;
 148
 149 /* Patterns that match file names to be excluded.  */
 150 GLOBAL struct exclude *excluded;
 151
 152 enum exclusion_tag_type
 153   {
 154     exclusion_tag_none,
 155      /* Exclude the directory contents, but preserve the directory
 156         itself and the exclusion tag file */
 157     exclusion_tag_contents,
 158     /* Exclude everything below the directory, preserving the directory
 159        itself */
 160     exclusion_tag_under,
 161     /* Exclude entire directory  */
 162     exclusion_tag_all,
 163   };
 164
 165 /* Specified value to be put into tar file in place of stat () results, or
 166    just null and -1 if such an override should not take place.  */
 167 GLOBAL char const *group_name_option;
 168 GLOBAL gid_t group_option;
 169
 170 GLOBAL bool ignore_failed_read_option;
 171
 172 GLOBAL bool ignore_zeros_option;
 173
 174 GLOBAL bool incremental_option;
 175
 176 /* Specified name of script to run at end of each tape change.  */
 177 GLOBAL const char *info_script_option;
 178
 179 GLOBAL bool interactive_option;
 180
 181 /* If nonzero, extract only Nth occurrence of each named file */
 182 GLOBAL uintmax_t occurrence_option;
 183
 184 enum old_files
 185 {
 186   DEFAULT_OLD_FILES,          /* default */
 187   NO_OVERWRITE_DIR_OLD_FILES, /* --no-overwrite-dir */
 188   OVERWRITE_OLD_FILES,        /* --overwrite */
 189   UNLINK_FIRST_OLD_FILES,     /* --unlink-first */
 190   KEEP_OLD_FILES,             /* --keep-old-files */
 191   SKIP_OLD_FILES,             /* --skip-old-files */
 192   KEEP_NEWER_FILES            /* --keep-newer-files */
 193 };
 194 GLOBAL enum old_files old_files_option;
 195
 196 GLOBAL bool keep_directory_symlink_option;
 197
 198 /* Specified file name for incremental list.  */
 199 GLOBAL const char *listed_incremental_option;
 200 /* Incremental dump level */
 201 GLOBAL int incremental_level;
 202 /* Check device numbers when doing incremental dumps. */
 203 GLOBAL bool check_device_option;
 204
 205 /* Specified mode change string.  */
 206 GLOBAL struct mode_change *mode_option;
 207
 208 /* Initial umask, if needed for mode change string.  */
 209 GLOBAL mode_t initial_umask;
 210
 211 GLOBAL 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).  */
 215 GLOBAL struct timespec newer_mtime_option;
 216
 217 enum set_mtime_option_mode
 218 {
 219   USE_FILE_MTIME,
 220   FORCE_MTIME,
 221   CLAMP_MTIME,
 222   COMMAND_MTIME,
 223 };
 224
 225 /* Override actual mtime if set to FORCE_MTIME or CLAMP_MTIME */
 226 GLOBAL enum set_mtime_option_mode set_mtime_option;
 227 /* Value to use when forcing or clamping the mtime header field. */
 228 GLOBAL struct timespec mtime_option;
 229
 230 /* Command to use to set mtime when archiving. */
 231 GLOBAL char *set_mtime_command;
 232
 233 /* Format (as per strptime(3)) of the output of the above command.  If
 234    not set, parse_datetime will be used. */
 235 GLOBAL char *set_mtime_format;
 236
 237 /* Return true if mtime_option or newer_mtime_option is initialized.  */
 238 #define TIME_OPTION_INITIALIZED(opt) (0 <= (opt).tv_nsec)
 239
 240 /* Return true if the struct stat ST's M time is less than
 241    newer_mtime_option.  */
 242 #define OLDER_STAT_TIME(st, m) \
 243   (timespec_cmp (get_stat_##m##time (&(st)), newer_mtime_option) < 0)
 244
 245 /* Likewise, for struct tar_stat_info ST.  */
 246 #define OLDER_TAR_STAT_TIME(st, m) \
 247   (timespec_cmp ((st).m##time, newer_mtime_option) < 0)
 248
 249 /* Zero if there is no recursion, otherwise FNM_LEADING_DIR.  */
 250 GLOBAL int recursion_option;
 251
 252 GLOBAL bool numeric_owner_option;
 253
 254 GLOBAL bool one_file_system_option;
 255
 256 /* Create a top-level directory for extracting based on the archive name.  */
 257 GLOBAL bool one_top_level_option;
 258 GLOBAL char *one_top_level_dir;
 259
 260 /* Specified value to be put into tar file in place of stat () results, or
 261    just null and -1 if such an override should not take place.  */
 262 GLOBAL char const *owner_name_option;
 263 GLOBAL uid_t owner_option;
 264
 265 GLOBAL bool recursive_unlink_option;
 266
 267 GLOBAL bool read_full_records_option;
 268
 269 GLOBAL bool remove_files_option;
 270
 271 /* Specified remote shell command.  */
 272 GLOBAL const char *rsh_command_option;
 273
 274 GLOBAL bool same_order_option;
 275
 276 /* If positive, preserve ownership when extracting.  */
 277 GLOBAL int same_owner_option;
 278
 279 /* If positive, preserve permissions when extracting.  */
 280 GLOBAL int same_permissions_option;
 281
 282 /* If positive, save the SELinux context.  */
 283 GLOBAL int selinux_context_option;
 284
 285 /* If positive, save the ACLs.  */
 286 GLOBAL int acls_option;
 287
 288 /* If positive, save the user and root xattrs.  */
 289 GLOBAL int xattrs_option;
 290
 291 /* When set, strip the given number of file name components from the file name
 292    before extracting */
 293 GLOBAL size_t strip_name_components;
 294
 295 GLOBAL bool show_omitted_dirs_option;
 296
 297 GLOBAL bool sparse_option;
 298 GLOBAL unsigned tar_sparse_major;
 299 GLOBAL unsigned tar_sparse_minor;
 300
 301 enum hole_detection_method
 302   {
 303     HOLE_DETECTION_DEFAULT,
 304     HOLE_DETECTION_RAW,
 305     HOLE_DETECTION_SEEK
 306   };
 307
 308 GLOBAL enum hole_detection_method hole_detection;
 309
 310 /* The first entry in names.c:namelist specifies the member name to
 311    start extracting from. Set by add_starting_file() upon seeing the
 312    -K option.
 313 */
 314 GLOBAL bool starting_file_option;
 315
 316 /* Specified maximum byte length of each tape volume (multiple of 1024).  */
 317 GLOBAL tarlong tape_length_option;
 318
 319 GLOBAL bool to_stdout_option;
 320
 321 GLOBAL bool totals_option;
 322
 323 GLOBAL bool touch_option;
 324
 325 GLOBAL char *to_command_option;
 326 GLOBAL bool ignore_command_error_option;
 327
 328 /* Restrict some potentially harmful tar options */
 329 GLOBAL bool restrict_option;
 330
 331 /* Return true if the extracted files are not being written to disk */
 332 #define EXTRACT_OVER_PIPE (to_stdout_option || to_command_option)
 333
 334 /* Count how many times the option has been set, multiple setting yields
 335    more verbose behavior.  Value 0 means no verbosity, 1 means file name
 336    only, 2 means file name and all attributes.  More than 2 is just like 2.  */
 337 GLOBAL int verbose_option;
 338
 339 GLOBAL bool verify_option;
 340
 341 /* Specified name of file containing the volume number.  */
 342 GLOBAL const char *volno_file_option;
 343
 344 /* Specified value or pattern.  */
 345 GLOBAL const char *volume_label_option;
 346 \f
 347 /* Other global variables.  */
 348
 349 /* Force POSIX-compliance */
 350 GLOBAL bool posixly_correct;
 351
 352 /* File descriptor for archive file.  */
 353 GLOBAL int archive;
 354
 355 /* Nonzero when outputting to /dev/null.  */
 356 GLOBAL bool dev_null_output;
 357
 358 /* Timestamps: */
 359 GLOBAL struct timespec start_time;        /* when we started execution */
 360 GLOBAL struct timespec volume_start_time; /* when the current volume was
 361                                              opened*/
 362 GLOBAL struct timespec last_stat_time;    /* when the statistics was last
 363                                              computed */
 364
 365 GLOBAL struct tar_stat_info current_stat_info;
 366
 367 /* List of tape drive names, number of such tape drives,
 368    and current cursor in list.  */
 369 GLOBAL const char **archive_name_array;
 370 GLOBAL size_t archive_names;
 371 GLOBAL const char **archive_name_cursor;
 372
 373 /* Output index file name.  */
 374 GLOBAL char const *index_file_name;
 375
 376 /* Opaque structure for keeping directory meta-data */
 377 struct directory;
 378
 379 /* Structure for keeping track of filenames and lists thereof.  */
 380 struct name
 381   {
 382     struct name *next;          /* Link to the next element */
 383     struct name *prev;          /* Link to the previous element */
 384
 385     char *name;                 /* File name or globbing pattern */
 386     size_t length;              /* cached strlen (name) */
 387     int matching_flags;         /* wildcard flags if name is a pattern */
 388     bool is_wildcard;           /* true if this is a wildcard pattern */
 389     bool cmdline;               /* true if this name was given in the
 390                                    command line */
 391
 392     int change_dir;             /* Number of the directory to change to.
 393                                    Set with the -C option. */
 394     uintmax_t found_count;      /* number of times a matching file has
 395                                    been found */
 396
 397     /* The following members are used for incremental dumps only,
 398        if this struct name represents a directory;
 399        see incremen.c */
 400     struct directory *directory;/* directory meta-data and contents */
 401     struct name *parent;        /* pointer to the parent hierarchy */
 402     struct name *child;         /* pointer to the first child */
 403     struct name *sibling;       /* pointer to the next sibling */
 404     char *caname;               /* canonical name */
 405   };
 406
 407 /* Status of archive file, or all zeros if remote.  */
 408 GLOBAL struct stat archive_stat;
 409
 410 /* Flags for reading, searching, and fstatatting files.  */
 411 GLOBAL int open_read_flags;
 412 GLOBAL int open_searchdir_flags;
 413 GLOBAL int fstatat_flags;
 414
 415 GLOBAL int seek_option;
 416
 417 /* true if archive if lseek should be used on the archive, 0 if it
 418    should not be used.  */
 419 GLOBAL bool seekable_archive;
 420
 421 GLOBAL dev_t root_device;
 422
 423 /* Unquote filenames */
 424 GLOBAL bool unquote_option;
 425
 426 GLOBAL int savedir_sort_order;
 427
 428 /* Show file or archive names after transformation.
 429    In particular, when creating archive in verbose mode, list member names
 430    as stored in the archive */
 431 GLOBAL bool show_transformed_names_option;
 432
 433 /* Delay setting modification times and permissions of extracted directories
 434    until the end of extraction. This variable helps correctly restore directory
 435    timestamps from archives with an unusual member order. It is automatically
 436    set for incremental archives. */
 437 GLOBAL bool delay_directory_restore_option;
 438 \f
 439 /* Declarations for each module.  */
 440
 441 /* FIXME: compare.c should not directly handle the following variable,
 442    instead, this should be done in buffer.c only.  */
 443
 444 enum access_mode
 445 {
 446   ACCESS_READ,
 447   ACCESS_WRITE,
 448   ACCESS_UPDATE
 449 };
 450 extern enum access_mode access_mode;
 451
 452 /* Module buffer.c.  */
 453
 454 extern FILE *stdlis;
 455 extern bool write_archive_to_stdout;
 456 extern char *volume_label;
 457 extern size_t volume_label_count;
 458 extern char *continued_file_name;
 459 extern uintmax_t continued_file_size;
 460 extern uintmax_t continued_file_offset;
 461 extern off_t records_written;
 462
 463 char *drop_volume_label_suffix (const char *label);
 464
 465 size_t available_space_after (union block *pointer);
 466 off_t current_block_ordinal (void);
 467 void close_archive (void);
 468 void closeout_volume_number (void);
 469 double compute_duration (void);
 470 union block *find_next_block (void);
 471 void flush_read (void);
 472 void flush_write (void);
 473 void flush_archive (void);
 474 void init_volume_number (void);
 475 void open_archive (enum access_mode mode);
 476 void print_total_stats (void);
 477 void reset_eof (void);
 478 void set_next_block_after (union block *block);
 479 void clear_read_error_count (void);
 480 void xclose (int fd);
 481 _Noreturn void archive_write_error (ssize_t status);
 482 void archive_read_error (void);
 483 off_t seek_archive (off_t size);
 484 void set_start_time (void);
 485
 486 #define TF_READ    0
 487 #define TF_WRITE   1
 488 #define TF_DELETED 2
 489 int format_total_stats (FILE *fp, char const *const *formats, int eor, int eol);
 490 void print_total_stats (void);
 491
 492 void mv_begin_write (const char *file_name, off_t totsize, off_t sizeleft);
 493
 494 void mv_begin_read (struct tar_stat_info *st);
 495 void mv_end (void);
 496 void mv_size_left (off_t size);
 497
 498 void buffer_write_global_xheader (void);
 499
 500 const char *first_decompress_program (int *pstate);
 501 const char *next_decompress_program (int *pstate);
 502
 503 /* Module create.c.  */
 504
 505 enum dump_status
 506   {
 507     dump_status_ok,
 508     dump_status_short,
 509     dump_status_fail,
 510     dump_status_not_implemented
 511   };
 512
 513 void add_exclusion_tag (const char *name, enum exclusion_tag_type type,
 514                         bool (*predicate) (int));
 515 bool cachedir_file_p (int fd);
 516 char *get_directory_entries (struct tar_stat_info *st)
 517   _GL_ATTRIBUTE_MALLOC _GL_ATTRIBUTE_DEALLOC_FREE;
 518
 519 void create_archive (void);
 520 void pad_archive (off_t size_left);
 521 void dump_file (struct tar_stat_info *parent, char const *name,
 522                 char const *fullname);
 523 union block *start_header (struct tar_stat_info *st);
 524 void finish_header (struct tar_stat_info *st, union block *header,
 525                     off_t block_ordinal);
 526 void simple_finish_header (union block *header);
 527 union block * write_extended (bool global, struct tar_stat_info *st,
 528                               union block *old_header);
 529 union block *start_private_header (const char *name, size_t size, time_t t);
 530 void write_eot (void);
 531 void check_links (void);
 532 int subfile_open (struct tar_stat_info const *dir, char const *file, int flags);
 533 void restore_parent_fd (struct tar_stat_info const *st);
 534 void exclusion_tag_warning (const char *dirname, const char *tagname,
 535                             const char *message);
 536 enum exclusion_tag_type check_exclusion_tags (struct tar_stat_info const *st,
 537                                               const char **tag_file_name);
 538
 539 #define OFF_TO_CHARS(val, where) off_to_chars (val, where, sizeof (where))
 540 #define TIME_TO_CHARS(val, where) time_to_chars (val, where, sizeof (where))
 541
 542 bool off_to_chars (off_t off, char *buf, size_t size);
 543 bool time_to_chars (time_t t, char *buf, size_t size);
 544
 545 /* Module diffarch.c.  */
 546
 547 extern bool now_verifying;
 548
 549 void diff_archive (void);
 550 void diff_init (void);
 551 void verify_volume (void);
 552
 553 /* Module extract.c.  */
 554
 555 void extr_init (void);
 556 void extract_archive (void);
 557 void extract_finish (void);
 558 bool rename_directory (char *src, char *dst);
 559
 560 void remove_delayed_set_stat (const char *fname);
 561
 562 /* Module delete.c.  */
 563
 564 void delete_archive_members (void);
 565
 566 /* Module incremen.c.  */
 567
 568 struct directory *scan_directory (struct tar_stat_info *st);
 569 const char *directory_contents (struct directory *dir);
 570 const char *safe_directory_contents (struct directory *dir);
 571
 572 void rebase_directory (struct directory *dir,
 573                        const char *samp, size_t slen,
 574                        const char *repl, size_t rlen);
 575
 576 void append_incremental_renames (struct directory *dir);
 577 void show_snapshot_field_ranges (void);
 578 void read_directory_file (void);
 579 void write_directory_file (void);
 580 void purge_directory (char const *directory_name);
 581 void list_dumpdir (char *buffer, size_t size);
 582 void update_parent_directory (struct tar_stat_info *st);
 583
 584 size_t dumpdir_size (const char *p);
 585 bool is_dumpdir (struct tar_stat_info *stat_info);
 586 void clear_directory_table (void);
 587
 588 /* Module list.c.  */
 589
 590 enum read_header
 591 {
 592   HEADER_STILL_UNREAD,          /* for when read_header has not been called */
 593   HEADER_SUCCESS,               /* header successfully read and checksummed */
 594   HEADER_SUCCESS_EXTENDED,      /* likewise, but we got an extended header */
 595   HEADER_ZERO_BLOCK,            /* zero block where header expected */
 596   HEADER_END_OF_FILE,           /* true end of file while header expected */
 597   HEADER_FAILURE                /* ill-formed header, or bad checksum */
 598 };
 599
 600 /* Operation mode for read_header: */
 601
 602 enum read_header_mode
 603 {
 604   read_header_auto,             /* process extended headers automatically */
 605   read_header_x_raw,            /* return raw extended headers (return
 606                                    HEADER_SUCCESS_EXTENDED) */
 607   read_header_x_global          /* when POSIX global extended header is read,
 608                                    decode it and return
 609                                    HEADER_SUCCESS_EXTENDED */
 610 };
 611 extern union block *current_header;
 612 extern enum archive_format current_format;
 613 extern size_t recent_long_name_blocks;
 614 extern size_t recent_long_link_blocks;
 615
 616 void decode_header (union block *header, struct tar_stat_info *stat_info,
 617                     enum archive_format *format_pointer, int do_user_group);
 618 void transform_stat_info (int typeflag, struct tar_stat_info *stat_info);
 619 char const *tartime (struct timespec t, bool full_time);
 620
 621 #define OFF_FROM_HEADER(where) off_from_header (where, sizeof (where))
 622 #define UINTMAX_FROM_HEADER(where) uintmax_from_header (where, sizeof (where))
 623
 624 off_t off_from_header (const char *buf, size_t size);
 625 uintmax_t uintmax_from_header (const char *buf, size_t size);
 626
 627 void list_archive (void);
 628 void test_archive_label (void);
 629 void print_for_mkdir (char *dirname, mode_t mode);
 630 void print_header (struct tar_stat_info *st, union block *blk,
 631                    off_t block_ordinal);
 632 void read_and (void (*do_something) (void));
 633 enum read_header read_header (union block **return_block,
 634                               struct tar_stat_info *info,
 635                               enum read_header_mode m);
 636 enum read_header tar_checksum (union block *header, bool silent);
 637 void skim_file (off_t size, bool must_copy);
 638 void skip_member (void);
 639 void skim_member (bool must_copy);
 640
 641 /* Module misc.c.  */
 642
 643 #define min(a, b) ((a) < (b) ? (a) : (b))
 644 #define max(a, b) ((a) < (b) ? (b) : (a))
 645
 646 char const *quote_n_colon (int n, char const *arg);
 647 void assign_string_or_null (char **dest, const char *src)
 648   ATTRIBUTE_NONNULL ((1));
 649 void assign_string (char **dest, const char *src) ATTRIBUTE_NONNULL ((1, 2));
 650 void assign_null (char **dest) ATTRIBUTE_NONNULL ((1));
 651 void assign_string_n (char **string, const char *value, size_t n);
 652 #define ASSIGN_STRING_N(s,v) assign_string_n (s, v, sizeof (v))
 653 int unquote_string (char *str);
 654 char *zap_slashes (char *name);
 655 char *normalize_filename (int cdidx, const char *name);
 656 void normalize_filename_x (char *name);
 657 void replace_prefix (char **pname, const char *samp, size_t slen,
 658                      const char *repl, size_t rlen);
 659 char *tar_savedir (const char *name, int must_exist);
 660
 661 typedef struct namebuf *namebuf_t;
 662 namebuf_t namebuf_create (const char *dir);
 663 void namebuf_free (namebuf_t buf);
 664 char *namebuf_name (namebuf_t buf, const char *name);
 665
 666 const char *tar_dirname (void);
 667
 668 /* Represent N using a signed integer I such that (uintmax_t) I == N.
 669    With a good optimizing compiler, this is equivalent to (intmax_t) i
 670    and requires zero machine instructions.  */
 671 #if ! (UINTMAX_MAX / 2 <= INTMAX_MAX)
 672 # error "represent_uintmax returns intmax_t to represent uintmax_t"
 673 #endif
 674 COMMON_INLINE intmax_t
 675 represent_uintmax (uintmax_t n)
 676 {
 677   if (n <= INTMAX_MAX)
 678     return n;
 679   else
 680     {
 681       /* Avoid signed integer overflow on picky platforms.  */
 682       intmax_t nd = n - INTMAX_MIN;
 683       return nd + INTMAX_MIN;
 684     }
 685 }
 686
 687 #define STRINGIFY_BIGINT(i, b) umaxtostr (i, b)
 688 enum { UINTMAX_STRSIZE_BOUND = INT_BUFSIZE_BOUND (intmax_t) };
 689 enum { SYSINT_BUFSIZE =
 690          max (UINTMAX_STRSIZE_BOUND, INT_BUFSIZE_BOUND (intmax_t)) };
 691 char *sysinttostr (uintmax_t, intmax_t, uintmax_t, char buf[SYSINT_BUFSIZE]);
 692 intmax_t strtosysint (char const *, char **, intmax_t, uintmax_t);
 693 void code_ns_fraction (int ns, char *p);
 694 enum { BILLION = 1000000000, LOG10_BILLION = 9 };
 695 enum { TIMESPEC_STRSIZE_BOUND =
 696          UINTMAX_STRSIZE_BOUND + LOG10_BILLION + sizeof "-." - 1 };
 697 char const *code_timespec (struct timespec ts,
 698                            char sbuf[TIMESPEC_STRSIZE_BOUND]);
 699 struct timespec decode_timespec (char const *, char **, bool);
 700
 701 /* Return true if T does not represent an out-of-range or invalid value.  */
 702 COMMON_INLINE bool
 703 valid_timespec (struct timespec t)
 704 {
 705   return 0 <= t.tv_nsec;
 706 }
 707
 708 bool must_be_dot_or_slash (char const *);
 709
 710 enum remove_option
 711 {
 712   ORDINARY_REMOVE_OPTION,
 713   RECURSIVE_REMOVE_OPTION,
 714
 715   /* FIXME: The following value is never used. It seems to be intended
 716      as a placeholder for a hypothetical option that should instruct tar
 717      to recursively remove subdirectories in purge_directory(),
 718      as opposed to the functionality of --recursive-unlink
 719      (RECURSIVE_REMOVE_OPTION value), which removes them in
 720      prepare_to_extract() phase. However, with the addition of more
 721      meta-info to the incremental dumps, this should become unnecessary */
 722   WANT_DIRECTORY_REMOVE_OPTION
 723 };
 724 int remove_any_file (const char *file_name, enum remove_option option);
 725 bool maybe_backup_file (const char *file_name, bool this_is_the_archive);
 726 void undo_last_backup (void);
 727
 728 int deref_stat (char const *name, struct stat *buf);
 729
 730 size_t blocking_read (int fd, void *buf, size_t count);
 731 size_t blocking_write (int fd, void const *buf, size_t count);
 732
 733 extern int chdir_current;
 734 extern int chdir_fd;
 735 int chdir_arg (char const *dir);
 736 void chdir_do (int dir);
 737 int chdir_count (void);
 738
 739 void close_diag (char const *name);
 740 void open_diag (char const *name);
 741 void read_diag_details (char const *name, off_t offset, size_t size);
 742 void readlink_diag (char const *name);
 743 void savedir_diag (char const *name);
 744 void seek_diag_details (char const *name, off_t offset);
 745 void stat_diag (char const *name);
 746 void file_removed_diag (const char *name, bool top_level,
 747                         void (*diagfn) (char const *name));
 748 void write_error_details (char const *name, size_t status, size_t size);
 749 _Noreturn void write_fatal (char const *name);
 750 _Noreturn void write_fatal_details (char const *name, ssize_t status, size_t size);
 751
 752 pid_t xfork (void);
 753 void xpipe (int fd[2]);
 754
 755 void *page_aligned_alloc (void **ptr, size_t size);
 756 int set_file_atime (int fd, int parentfd, char const *file,
 757                     struct timespec atime);
 758
 759 /* Module names.c.  */
 760
 761 enum files_count
 762   {
 763     FILES_NONE,
 764     FILES_ONE,
 765     FILES_MANY
 766   };
 767 extern enum files_count filename_args;
 768
 769 /* Return true if there are file names in the list */
 770 COMMON_INLINE bool
 771 name_more_files (void)
 772 {
 773   return filename_args != FILES_NONE;
 774 }
 775
 776 extern struct name *gnu_list_name;
 777
 778 void gid_to_gname (gid_t gid, char **gname);
 779 int gname_to_gid (char const *gname, gid_t *pgid);
 780 void uid_to_uname (uid_t uid, char **uname);
 781 int uname_to_uid (char const *uname, uid_t *puid);
 782
 783 void name_init (void);
 784 void name_add_name (const char *name);
 785 void name_term (void);
 786 const char *name_next (int change_dirs);
 787 void name_gather (void);
 788 struct name *addname (char const *string, int change_dir,
 789                       bool cmdline, struct name *parent);
 790 void add_starting_file (char const *file_name);
 791 void remname (struct name *name);
 792 bool name_match (const char *name);
 793 void names_notfound (void);
 794 void label_notfound (void);
 795 void collect_and_sort_names (void);
 796 struct name *name_scan (const char *name, bool exact);
 797 struct name const *name_from_list (void);
 798 void blank_name_list (void);
 799 char *make_file_name (const char *dir_name, const char *name);
 800 size_t stripped_prefix_len (char const *file_name, size_t num);
 801 bool all_names_found (struct tar_stat_info *st);
 802
 803 void add_avoided_name (char const *name);
 804 bool is_avoided_name (char const *name);
 805
 806 bool contains_dot_dot (char const *name);
 807
 808 #define ISFOUND(c) (occurrence_option == 0                      \
 809                     ? (c)->found_count != 0                     \
 810                     : (c)->found_count == occurrence_option)
 811 #define WASFOUND(c) (occurrence_option == 0                     \
 812                      ? (c)->found_count != 0                    \
 813                      : (c)->found_count >= occurrence_option)
 814
 815 /* Module tar.c.  */
 816
 817 _Noreturn void usage (int);
 818
 819 int confirm (const char *message_action, const char *name);
 820
 821 void tar_stat_init (struct tar_stat_info *st);
 822 bool tar_stat_close (struct tar_stat_info *st);
 823 void tar_stat_destroy (struct tar_stat_info *st);
 824 _Noreturn void usage (int);
 825 int tar_timespec_cmp (struct timespec a, struct timespec b);
 826 const char *archive_format_string (enum archive_format fmt);
 827 const char *subcommand_string (enum subcommand c);
 828 void set_exit_status (int val);
 829
 830 void request_stdin (const char *option);
 831
 832 int decode_signal (const char *);
 833
 834 /* Where an option comes from: */
 835 enum option_source
 836   {
 837     OPTS_ENVIRON,        /* Environment variable TAR_OPTIONS */
 838     OPTS_COMMAND_LINE,   /* Command line */
 839     OPTS_FILE            /* File supplied by --files-from */
 840   };
 841
 842 /* Option location */
 843 struct option_locus
 844 {
 845   enum option_source source;  /* Option origin */
 846   char const *name;           /* File or variable name */
 847   size_t line;                /* Number of input line if source is OPTS_FILE */
 848   struct option_locus *prev;  /* Previous occurrence of the option of same
 849                                  class */
 850 };
 851
 852 struct tar_args        /* Variables used during option parsing */
 853 {
 854   struct option_locus *loc;
 855
 856   struct textual_date *textual_date; /* Keeps the arguments to --newer-mtime
 857                                         and/or --date option if they are
 858                                         textual dates */
 859   bool o_option;                   /* True if -o option was given */
 860   bool pax_option;                 /* True if --pax-option was given */
 861   bool compress_autodetect;        /* True if compression autodetection should
 862                                       be attempted when creating archives */
 863   char const *backup_suffix_string;   /* --suffix option argument */
 864   char const *version_control_string; /* --backup option argument */
 865 };
 866
 867 #define TAR_ARGS_INITIALIZER(loc)              \
 868   { loc, NULL, false, false, false, NULL, NULL }
 869
 870 void more_options (int argc, char **argv, struct option_locus *loc);
 871
 872 /* Module update.c.  */
 873
 874 extern char *output_start;
 875
 876 void update_archive (void);
 877
 878 /* Module attrs.c.  */
 879 #include "xattrs.h"
 880
 881 /* Module xheader.c.  */
 882
 883 void xheader_decode (struct tar_stat_info *stat);
 884 void xheader_decode_global (struct xheader *xhdr);
 885 void xheader_store (char const *keyword, struct tar_stat_info *st,
 886                     void const *data);
 887 void xheader_read (struct xheader *xhdr, union block *header, off_t size);
 888 void xheader_write (char type, char *name, time_t t, struct xheader *xhdr);
 889 void xheader_write_global (struct xheader *xhdr);
 890 void xheader_forbid_global (void);
 891 void xheader_finish (struct xheader *hdr);
 892 void xheader_destroy (struct xheader *hdr);
 893 char *xheader_xhdr_name (struct tar_stat_info *st);
 894 char *xheader_ghdr_name (void);
 895 void xheader_set_option (char *string);
 896 void xheader_string_begin (struct xheader *xhdr);
 897 void xheader_string_add (struct xheader *xhdr, char const *s);
 898 bool xheader_string_end (struct xheader *xhdr, char const *keyword);
 899 bool xheader_keyword_deleted_p (const char *kw);
 900 char *xheader_format_name (struct tar_stat_info *st, const char *fmt,
 901                            size_t n);
 902 void xheader_xattr_init (struct tar_stat_info *st);
 903 void xheader_xattr_add (struct tar_stat_info *st,
 904                         const char *key, const char *val, size_t len);
 905
 906 void xattr_map_init (struct xattr_map *map);
 907 void xattr_map_copy (struct xattr_map *dst,
 908                      const struct xattr_map *src);
 909 void xattr_map_add (struct xattr_map *map,
 910                     const char *key, const char *val, size_t len);
 911 void xattr_map_free (struct xattr_map *xattr_map);
 912
 913 /* Module system.c */
 914
 915 void sys_detect_dev_null_output (void);
 916 void sys_wait_for_child (pid_t, bool);
 917 void sys_spawn_shell (void);
 918 bool sys_compare_uid (struct stat *a, struct stat *b);
 919 bool sys_compare_gid (struct stat *a, struct stat *b);
 920 bool sys_file_is_archive (struct tar_stat_info *p);
 921 bool sys_compare_links (struct stat *link_data, struct stat *stat_data);
 922 int sys_truncate (int fd);
 923 pid_t sys_child_open_for_compress (void);
 924 pid_t sys_child_open_for_uncompress (void);
 925 size_t sys_write_archive_buffer (void);
 926 bool sys_get_archive_stat (void);
 927 int sys_exec_command (char *file_name, int typechar, struct tar_stat_info *st);
 928 void sys_wait_command (void);
 929 int sys_exec_info_script (const char **archive_name, int volume_number);
 930 void sys_exec_checkpoint_script (const char *script_name,
 931                                  const char *archive_name,
 932                                  int checkpoint_number);
 933 bool mtioseek (bool count_files, off_t count);
 934 int sys_exec_setmtime_script (const char *script_name,
 935                               int dirfd,
 936                               const char *file_name,
 937                               const char *fmt,
 938                               struct timespec *ts);
 939
 940 /* Module compare.c */
 941 void report_difference (struct tar_stat_info *st, const char *message, ...)
 942   ATTRIBUTE_FORMAT ((printf, 2, 3));
 943
 944 /* Module sparse.c */
 945 bool sparse_member_p (struct tar_stat_info *st);
 946 bool sparse_fixup_header (struct tar_stat_info *st);
 947 enum dump_status sparse_dump_file (int, struct tar_stat_info *st);
 948 enum dump_status sparse_extract_file (int fd, struct tar_stat_info *st,
 949                                       off_t *size);
 950 enum dump_status sparse_skim_file (struct tar_stat_info *st, bool must_copy);
 951 bool sparse_diff_file (int, struct tar_stat_info *st);
 952
 953 /* Module utf8.c */
 954 bool string_ascii_p (const char *str);
 955 bool utf8_convert (bool to_utf, char const *input, char **output);
 956
 957 /* Module transform.c */
 958 #define XFORM_REGFILE  0x01
 959 #define XFORM_LINK     0x02
 960 #define XFORM_SYMLINK  0x04
 961 #define XFORM_ALL      (XFORM_REGFILE|XFORM_LINK|XFORM_SYMLINK)
 962
 963 void set_transform_expr (const char *expr);
 964 bool transform_name (char **pinput, int type);
 965 bool transform_name_fp (char **pinput, int type,
 966                         char *(*fun)(char *, void *), void *);
 967 bool transform_program_p (void);
 968
 969 /* Module suffix.c */
 970 void set_compression_program_by_suffix (const char *name, const char *defprog);
 971 char *strip_compression_suffix (const char *name);
 972
 973 /* Module checkpoint.c */
 974 void checkpoint_compile_action (const char *str);
 975 void checkpoint_finish_compile (void);
 976 void checkpoint_run (bool do_write);
 977 void checkpoint_finish (void);
 978 void checkpoint_flush_actions (void);
 979
 980 /* Module warning.c */
 981 #define WARN_ALONE_ZERO_BLOCK    0x00000001
 982 #define WARN_BAD_DUMPDIR         0x00000002
 983 #define WARN_CACHEDIR            0x00000004
 984 #define WARN_CONTIGUOUS_CAST     0x00000008
 985 #define WARN_FILE_CHANGED        0x00000010
 986 #define WARN_FILE_IGNORED        0x00000020
 987 #define WARN_FILE_REMOVED        0x00000040
 988 #define WARN_FILE_SHRANK         0x00000080
 989 #define WARN_FILE_UNCHANGED      0x00000100
 990 #define WARN_FILENAME_WITH_NULS  0x00000200
 991 #define WARN_IGNORE_ARCHIVE      0x00000400
 992 #define WARN_IGNORE_NEWER        0x00000800
 993 #define WARN_NEW_DIRECTORY       0x00001000
 994 #define WARN_RENAME_DIRECTORY    0x00002000
 995 #define WARN_SYMLINK_CAST        0x00004000
 996 #define WARN_TIMESTAMP           0x00008000
 997 #define WARN_UNKNOWN_CAST        0x00010000
 998 #define WARN_UNKNOWN_KEYWORD     0x00020000
 999 #define WARN_XDEV                0x00040000
1000 #define WARN_DECOMPRESS_PROGRAM  0x00080000
1001 #define WARN_EXISTING_FILE       0x00100000
1002 #define WARN_XATTR_WRITE         0x00200000
1003 #define WARN_RECORD_SIZE         0x00400000
1004 #define WARN_FAILED_READ         0x00800000
1005 #define WARN_MISSING_ZERO_BLOCKS 0x01000000
1006
1007 /* These warnings are enabled by default in verbose mode: */
1008 #define WARN_VERBOSE_WARNINGS    (WARN_RENAME_DIRECTORY|WARN_NEW_DIRECTORY|\
1009                                   WARN_DECOMPRESS_PROGRAM|WARN_EXISTING_FILE|\
1010                                   WARN_RECORD_SIZE)
1011 #define WARN_ALL                 0xffffffff
1012
1013 void set_warning_option (const char *arg);
1014
1015 extern int warning_option;
1016
1017 #define WARNING_ENABLED(opt) (warning_option & (opt))
1018
1019 #define WARNOPT(opt,args)                       \
1020   do                                            \
1021     {                                           \
1022       if (WARNING_ENABLED(opt)) WARN (args);    \
1023     }                                           \
1024   while (0)
1025
1026 /* Module unlink.c */
1027
1028 void queue_deferred_unlink (const char *name, bool is_dir);
1029 void finish_deferred_unlinks (void);
1030
1031 /* Module exit.c */
1032 extern void (*fatal_exit_hook) (void);
1033
1034 /* Module exclist.c */
1035 #define EXCL_DEFAULT       0x00
1036 #define EXCL_RECURSIVE     0x01
1037 #define EXCL_NON_RECURSIVE 0x02
1038
1039 void excfile_add (const char *name, int flags);
1040 void info_attach_exclist (struct tar_stat_info *dir);
1041 void info_free_exclist (struct tar_stat_info *dir);
1042 bool excluded_name (char const *name, struct tar_stat_info *st);
1043 void exclude_vcs_ignores (void);
1044
1045 /* Module map.c */
1046 void owner_map_read (char const *name);
1047 int owner_map_translate (uid_t uid, uid_t *new_uid, char const **new_name);
1048 void group_map_read (char const *file);
1049 int group_map_translate (gid_t gid, gid_t *new_gid, char const **new_name);
1050
1051
1052 _GL_INLINE_HEADER_END