/* Create a tar archive. Copyright 1985,92,93,94,96,97,99,2000, 2001 Free Software Foundation, Inc. Written by John Gilmore, on 1985-08-25. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "system.h" #if !MSDOS # include # include #endif #if HAVE_UTIME_H # include #else struct utimbuf { long actime; long modtime; }; #endif #include #include "common.h" #include #ifndef MSDOS extern dev_t ar_dev; extern ino_t ar_ino; #endif struct link { dev_t dev; ino_t ino; char name[1]; }; /* The maximum uintmax_t value that can be represented with DIGITS digits, assuming that each digit is BITS_PER_DIGIT wide. */ #define MAX_VAL_WITH_DIGITS(digits, bits_per_digit) \ ((digits) * (bits_per_digit) < sizeof (uintmax_t) * CHAR_BIT \ ? ((uintmax_t) 1 << ((digits) * (bits_per_digit))) - 1 \ : (uintmax_t) -1) /* Convert VALUE to an octal representation suitable for tar headers. Output to buffer WHERE with size SIZE. The result is undefined if SIZE is 0 or if VALUE is too large to fit. */ static void to_octal (uintmax_t value, char *where, size_t size) { uintmax_t v = value; size_t i = size; do { where[--i] = '0' + (v & ((1 << LG_8) - 1)); v >>= LG_8; } while (i); } /* Convert NEGATIVE VALUE to a base-256 representation suitable for tar headers. NEGATIVE is 1 if VALUE was negative before being cast to uintmax_t, 0 otherwise. Output to buffer WHERE with size SIZE. The result is undefined if SIZE is 0 or if VALUE is too large to fit. */ static void to_base256 (int negative, uintmax_t value, char *where, size_t size) { uintmax_t v = value; uintmax_t propagated_sign_bits = ((uintmax_t) - negative << (CHAR_BIT * sizeof v - LG_256)); size_t i = size; do { where[--i] = v & ((1 << LG_256) - 1); v = propagated_sign_bits | (v >> LG_256); } while (i); } /* Convert NEGATIVE VALUE (which was originally of size VALSIZE) to external form, using SUBSTITUTE (...) if VALUE won't fit. Output to buffer WHERE with size SIZE. NEGATIVE is 1 iff VALUE was negative before being cast to uintmax_t; its original bitpattern can be deduced from VALSIZE, its original size before casting. TYPE is the kind of value being output (useful for diagnostics). Prefer the POSIX format of SIZE - 1 octal digits (with leading zero digits), followed by '\0'. If this won't work, and if GNU or OLDGNU format is allowed, use '\200' followed by base-256, or (if NEGATIVE is nonzero) '\377' followed by two's complement base-256. If neither format works, use SUBSTITUTE (...) instead. Pass to SUBSTITUTE the address of an 0-or-1 flag recording whether the substitute value is negative. */ static void to_chars (int negative, uintmax_t value, size_t valsize, uintmax_t (*substitute) PARAMS ((int *)), char *where, size_t size, const char *type) { int base256_allowed = (archive_format == GNU_FORMAT || archive_format == OLDGNU_FORMAT); /* Generate the POSIX octal representation if the number fits. */ if (! negative && value <= MAX_VAL_WITH_DIGITS (size - 1, LG_8)) { where[size - 1] = '\0'; to_octal (value, where, size - 1); } /* Otherwise, generate the base-256 representation if we are generating an old or new GNU format and if the number fits. */ else if (((negative ? -1 - value : value) <= MAX_VAL_WITH_DIGITS (size - 1, LG_256)) && base256_allowed) { where[0] = negative ? -1 : 1 << (LG_256 - 1); to_base256 (negative, value, where + 1, size - 1); } /* Otherwise, if the number is negative, and if it would not cause ambiguity on this host by confusing positive with negative values, then generate the POSIX octal representation of the value modulo 2**(field bits). The resulting tar file is machine-dependent, since it depends on the host word size. Yuck! But this is the traditional behavior. */ else if (negative && valsize * CHAR_BIT <= (size - 1) * LG_8) { static int warned_once; if (! warned_once) { warned_once = 1; WARN ((0, 0, _("Generating negative octal headers"))); } where[size - 1] = '\0'; to_octal (value & MAX_VAL_WITH_DIGITS (valsize * CHAR_BIT, 1), where, size - 1); } /* Otherwise, output a substitute value if possible (with a warning), and an error message if not. */ else { uintmax_t maxval = (base256_allowed ? MAX_VAL_WITH_DIGITS (size - 1, LG_256) : MAX_VAL_WITH_DIGITS (size - 1, LG_8)); char valbuf[UINTMAX_STRSIZE_BOUND + 1]; char maxbuf[UINTMAX_STRSIZE_BOUND]; char minbuf[UINTMAX_STRSIZE_BOUND + 1]; char const *minval_string; char const *maxval_string = STRINGIFY_BIGINT (maxval, maxbuf); char const *value_string; if (base256_allowed) { uintmax_t m = maxval + 1 ? maxval + 1 : maxval / 2 + 1; char *p = STRINGIFY_BIGINT (m, minbuf + 1); *--p = '-'; minval_string = p; } else minval_string = "0"; if (negative) { char *p = STRINGIFY_BIGINT (- value, valbuf + 1); *--p = '-'; value_string = p; } else value_string = STRINGIFY_BIGINT (value, valbuf); if (substitute) { int negsub; uintmax_t sub = substitute (&negsub) & maxval; uintmax_t s = (negsub &= archive_format == GNU_FORMAT) ? - sub : sub; char subbuf[UINTMAX_STRSIZE_BOUND + 1]; char *sub_string = STRINGIFY_BIGINT (s, subbuf + 1); if (negsub) *--sub_string = '-'; WARN ((0, 0, _("value %s out of %s range %s..%s; substituting %s"), value_string, type, minval_string, maxval_string, sub_string)); to_chars (negsub, s, valsize, 0, where, size, type); } else ERROR ((0, 0, _("value %s out of %s range %s..%s"), value_string, type, minval_string, maxval_string)); } } static uintmax_t gid_substitute (int *negative) { gid_t r; #ifdef GID_NOBODY r = GID_NOBODY; #else static gid_t gid_nobody; if (!gid_nobody && !gname_to_gid ("nobody", &gid_nobody)) gid_nobody = -2; r = gid_nobody; #endif *negative = r < 0; return r; } void gid_to_chars (gid_t v, char *p, size_t s) { to_chars (v < 0, (uintmax_t) v, sizeof v, gid_substitute, p, s, "gid_t"); } void major_to_chars (major_t v, char *p, size_t s) { to_chars (v < 0, (uintmax_t) v, sizeof v, 0, p, s, "major_t"); } void minor_to_chars (minor_t v, char *p, size_t s) { to_chars (v < 0, (uintmax_t) v, sizeof v, 0, p, s, "minor_t"); } void mode_to_chars (mode_t v, char *p, size_t s) { /* In the common case where the internal and external mode bits are the same, and we are not using POSIX or GNU format, propagate all unknown bits to the external mode. This matches historical practice. Otherwise, just copy the bits we know about. */ int negative; uintmax_t u; if (S_ISUID == TSUID && S_ISGID == TSGID && S_ISVTX == TSVTX && S_IRUSR == TUREAD && S_IWUSR == TUWRITE && S_IXUSR == TUEXEC && S_IRGRP == TGREAD && S_IWGRP == TGWRITE && S_IXGRP == TGEXEC && S_IROTH == TOREAD && S_IWOTH == TOWRITE && S_IXOTH == TOEXEC && archive_format != POSIX_FORMAT && archive_format != GNU_FORMAT) { negative = v < 0; u = v; } else { negative = 0; u = ((v & S_ISUID ? TSUID : 0) | (v & S_ISGID ? TSGID : 0) | (v & S_ISVTX ? TSVTX : 0) | (v & S_IRUSR ? TUREAD : 0) | (v & S_IWUSR ? TUWRITE : 0) | (v & S_IXUSR ? TUEXEC : 0) | (v & S_IRGRP ? TGREAD : 0) | (v & S_IWGRP ? TGWRITE : 0) | (v & S_IXGRP ? TGEXEC : 0) | (v & S_IROTH ? TOREAD : 0) | (v & S_IWOTH ? TOWRITE : 0) | (v & S_IXOTH ? TOEXEC : 0)); } to_chars (negative, u, sizeof v, 0, p, s, "mode_t"); } void off_to_chars (off_t v, char *p, size_t s) { to_chars (v < 0, (uintmax_t) v, sizeof v, 0, p, s, "off_t"); } void size_to_chars (size_t v, char *p, size_t s) { to_chars (0, (uintmax_t) v, sizeof v, 0, p, s, "size_t"); } void time_to_chars (time_t v, char *p, size_t s) { to_chars (v < 0, (uintmax_t) v, sizeof v, 0, p, s, "time_t"); } static uintmax_t uid_substitute (int *negative) { uid_t r; #ifdef UID_NOBODY r = UID_NOBODY; #else static uid_t uid_nobody; if (!uid_nobody && !uname_to_uid ("nobody", &uid_nobody)) uid_nobody = -2; r = uid_nobody; #endif *negative = r < 0; return r; } void uid_to_chars (uid_t v, char *p, size_t s) { to_chars (v < 0, (uintmax_t) v, sizeof v, uid_substitute, p, s, "uid_t"); } void uintmax_to_chars (uintmax_t v, char *p, size_t s) { to_chars (0, v, sizeof v, 0, p, s, "uintmax_t"); } /* Writing routines. */ /* Zero out the buffer so we don't confuse ourselves with leftover data. */ static void clear_buffer (char *buffer) { memset (buffer, 0, BLOCKSIZE); } /* Write the EOT block(s). Zero at least two blocks, through the end of the record. Old tar, as previous versions of GNU tar, writes garbage after two zeroed blocks. */ void write_eot (void) { union block *pointer = find_next_block (); memset (pointer->buffer, 0, BLOCKSIZE); set_next_block_after (pointer); pointer = find_next_block (); memset (pointer->buffer, 0, available_space_after (pointer)); set_next_block_after (pointer); } /* Write a GNUTYPE_LONGLINK or GNUTYPE_LONGNAME block. */ /* FIXME: Cross recursion between start_header and write_long! */ static union block *start_header PARAMS ((const char *, struct stat *)); static void write_long (const char *p, char type) { size_t size = strlen (p) + 1; size_t bufsize; union block *header; struct stat foo; memset (&foo, 0, sizeof foo); foo.st_size = size; header = start_header ("././@LongLink", &foo); header->header.typeflag = type; finish_header (header); header = find_next_block (); bufsize = available_space_after (header); while (bufsize < size) { memcpy (header->buffer, p, bufsize); p += bufsize; size -= bufsize; set_next_block_after (header + (bufsize - 1) / BLOCKSIZE); header = find_next_block (); bufsize = available_space_after (header); } memcpy (header->buffer, p, size); memset (header->buffer + size, 0, bufsize - size); set_next_block_after (header + (size - 1) / BLOCKSIZE); } /* Return a suffix of the file NAME that is a relative file name. Warn about `..' in file names. But return NAME if the user wants absolute file names. */ static char const * relativize (char const *name) { if (! absolute_names_option) { { static int warned_once; if (! warned_once && contains_dot_dot (name)) { warned_once = 1; WARN ((0, 0, _("Member names contain `..'"))); } } { size_t prefix_len = FILESYSTEM_PREFIX_LEN (name); while (ISSLASH (name[prefix_len])) prefix_len++; if (prefix_len) { static int warned_once; if (!warned_once) { warned_once = 1; WARN ((0, 0, _("Removing leading `%.*s' from member names"), (int) prefix_len, name)); } name += prefix_len; } } } return name; } /* Header handling. */ /* Make a header block for the file whose stat info is st, and return its address. */ static union block * start_header (const char *name, struct stat *st) { union block *header; name = relativize (name); if (sizeof header->header.name <= strlen (name)) write_long (name, GNUTYPE_LONGNAME); header = find_next_block (); memset (header->buffer, 0, sizeof (union block)); assign_string (¤t_file_name, name); strncpy (header->header.name, name, NAME_FIELD_SIZE); header->header.name[NAME_FIELD_SIZE - 1] = '\0'; /* Override some stat fields, if requested to do so. */ if (owner_option != (uid_t) -1) st->st_uid = owner_option; if (group_option != (gid_t) -1) st->st_gid = group_option; if (mode_option) st->st_mode = ((st->st_mode & ~MODE_ALL) | mode_adjust (st->st_mode, mode_option)); /* Paul Eggert tried the trivial test ($WRITER cf a b; $READER tvf a) for a few tars and came up with the following interoperability matrix: WRITER 1 2 3 4 5 6 7 8 9 READER . . . . . . . . . 1 = SunOS 4.2 tar # . . # # . . # # 2 = NEC SVR4.0.2 tar . . . # # . . # . 3 = Solaris 2.1 tar . . . . . . . . . 4 = GNU tar 1.11.1 . . . . . . . . . 5 = HP-UX 8.07 tar . . . . . . . . . 6 = Ultrix 4.1 . . . . . . . . . 7 = AIX 3.2 . . . . . . . . . 8 = Hitachi HI-UX 1.03 . . . . . . . . . 9 = Omron UNIOS-B 4.3BSD 1.60Beta . = works # = ``impossible file type'' The following mask for old archive removes the `#'s in column 4 above, thus making GNU tar both a universal donor and a universal acceptor for Paul's test. */ if (archive_format == V7_FORMAT) MODE_TO_CHARS (st->st_mode & MODE_ALL, header->header.mode); else MODE_TO_CHARS (st->st_mode, header->header.mode); UID_TO_CHARS (st->st_uid, header->header.uid); GID_TO_CHARS (st->st_gid, header->header.gid); OFF_TO_CHARS (st->st_size, header->header.size); TIME_TO_CHARS (st->st_mtime, header->header.mtime); if (incremental_option) if (archive_format == OLDGNU_FORMAT) { TIME_TO_CHARS (st->st_atime, header->oldgnu_header.atime); TIME_TO_CHARS (st->st_ctime, header->oldgnu_header.ctime); } header->header.typeflag = archive_format == V7_FORMAT ? AREGTYPE : REGTYPE; switch (archive_format) { case V7_FORMAT: break; case OLDGNU_FORMAT: /* Overwrite header->header.magic and header.version in one blow. */ strcpy (header->header.magic, OLDGNU_MAGIC); break; case POSIX_FORMAT: case GNU_FORMAT: strncpy (header->header.magic, TMAGIC, TMAGLEN); strncpy (header->header.version, TVERSION, TVERSLEN); break; default: abort (); } if (archive_format == V7_FORMAT || numeric_owner_option) { /* header->header.[ug]name are left as the empty string. */ } else { uid_to_uname (st->st_uid, header->header.uname); gid_to_gname (st->st_gid, header->header.gname); } return header; } /* Finish off a filled-in header block and write it out. We also print the file name and/or full info if verbose is on. */ void finish_header (union block *header) { size_t i; int sum; char *p; memcpy (header->header.chksum, CHKBLANKS, sizeof header->header.chksum); sum = 0; p = header->buffer; for (i = sizeof *header; i-- != 0; ) /* We can't use unsigned char here because of old compilers, e.g. V7. */ sum += 0xFF & *p++; /* Fill in the checksum field. It's formatted differently from the other fields: it has [6] digits, a null, then a space -- rather than digits, then a null. We use to_chars. The final space is already there, from checksumming, and to_chars doesn't modify it. This is a fast way to do: sprintf(header->header.chksum, "%6o", sum); */ uintmax_to_chars ((uintmax_t) sum, header->header.chksum, 7); if (verbose_option && header->header.typeflag != GNUTYPE_LONGLINK && header->header.typeflag != GNUTYPE_LONGNAME) { /* These globals are parameters to print_header, sigh. */ current_header = header; /* current_stat is already set up. */ current_format = archive_format; print_header (); } set_next_block_after (header); } /* Sparse file processing. */ /* Takes a blockful of data and basically cruises through it to see if it's made *entirely* of zeros, returning a 0 the instant it finds something that is a nonzero, i.e., useful data. */ static int zero_block_p (char *buffer) { int counter; for (counter = 0; counter < BLOCKSIZE; counter++) if (buffer[counter] != '\0') return 0; return 1; } static void init_sparsearray (void) { sp_array_size = 10; /* Make room for our scratch space -- initially is 10 elts long. */ sparsearray = xmalloc (sp_array_size * sizeof (struct sp_array)); } static off_t find_new_file_size (int sparses) { int i; off_t s = 0; for (i = 0; i < sparses; i++) s += sparsearray[i].numbytes; return s; } /* Make one pass over the file NAME, studying where any non-zero data is, that is, how far into the file each instance of data is, and how many bytes are there. Save this information in the sparsearray, which will later be translated into header information. */ /* There is little point in trimming small amounts of null data at the head and tail of blocks, only avoid dumping full null blocks. */ /* FIXME: this routine might accept bits of algorithmic cleanup, it is too kludgey for my taste... */ static int deal_with_sparse (char *name, union block *header) { size_t numbytes = 0; off_t offset = 0; int file; int sparses = 0; ssize_t count; char buffer[BLOCKSIZE]; if (archive_format == OLDGNU_FORMAT) header->oldgnu_header.isextended = 0; if (file = open (name, O_RDONLY), file < 0) /* This problem will be caught later on, so just return. */ return 0; init_sparsearray (); clear_buffer (buffer); for (;;) { /* Realloc the scratch area as necessary. FIXME: should reallocate only at beginning of a new instance of non-zero data. */ if (sp_array_size <= sparses) { sparsearray = xrealloc (sparsearray, 2 * sp_array_size * sizeof (struct sp_array)); sp_array_size *= 2; } count = safe_read (file, buffer, sizeof buffer); if (count <= 0) break; /* Process one block. */ if (count == sizeof buffer) if (zero_block_p (buffer)) { if (numbytes) { sparsearray[sparses++].numbytes = numbytes; numbytes = 0; } } else { if (!numbytes) sparsearray[sparses].offset = offset; numbytes += count; } else /* Since count < sizeof buffer, we have the last bit of the file. */ if (!zero_block_p (buffer)) { if (!numbytes) sparsearray[sparses].offset = offset; numbytes += count; } else /* The next two lines are suggested by Andreas Degert, who says they are required for trailing full blocks to be written to the archive, when all zeroed. Yet, it seems to me that the case does not apply. Further, at restore time, the file is not as sparse as it should. So, some serious cleanup is *also* needed in this area. Just one more... :-(. FIXME. */ if (numbytes) numbytes += count; /* Prepare for next block. */ offset += count; /* FIXME: do not clear unless necessary. */ clear_buffer (buffer); } if (numbytes) sparsearray[sparses++].numbytes = numbytes; else { sparsearray[sparses].offset = offset - 1; sparsearray[sparses++].numbytes = 1; } return close (file) == 0 && 0 <= count ? sparses : 0; } static int finish_sparse_file (int file, off_t *sizeleft, off_t fullsize, char *name) { union block *start; size_t bufsize; int sparses = 0; ssize_t count; while (*sizeleft > 0) { start = find_next_block (); memset (start->buffer, 0, BLOCKSIZE); bufsize = sparsearray[sparses].numbytes; if (! bufsize) abort (); if (lseek (file, sparsearray[sparses++].offset, SEEK_SET) < 0) { (ignore_failed_read_option ? seek_warn_details : seek_error_details) (name, sparsearray[sparses - 1].offset); break; } /* If the number of bytes to be written here exceeds the size of the temporary buffer, do it in steps. */ while (bufsize > BLOCKSIZE) { count = safe_read (file, start->buffer, BLOCKSIZE); if (count < 0) { (ignore_failed_read_option ? read_warn_details : read_error_details) (name, fullsize - *sizeleft, bufsize); return 1; } bufsize -= count; *sizeleft -= count; set_next_block_after (start); start = find_next_block (); memset (start->buffer, 0, BLOCKSIZE); } { char buffer[BLOCKSIZE]; clear_buffer (buffer); count = safe_read (file, buffer, bufsize); memcpy (start->buffer, buffer, BLOCKSIZE); } if (count < 0) { (ignore_failed_read_option ? read_warn_details : read_error_details) (name, fullsize - *sizeleft, bufsize); return 1; } *sizeleft -= count; set_next_block_after (start); } free (sparsearray); #if 0 set_next_block_after (start + (count - 1) / BLOCKSIZE); #endif return 0; } /* Main functions of this module. */ void create_archive (void) { char *p; open_archive (ACCESS_WRITE); if (incremental_option) { size_t buffer_size = 1000; char *buffer = xmalloc (buffer_size); const char *q; collect_and_sort_names (); while (p = name_from_list (), p) if (!excluded_name (p)) dump_file (p, -1, (dev_t) 0); blank_name_list (); while (p = name_from_list (), p) if (!excluded_name (p)) { size_t plen = strlen (p); if (buffer_size <= plen) { while ((buffer_size *= 2) <= plen) continue; buffer = xrealloc (buffer, buffer_size); } memcpy (buffer, p, plen); if (! ISSLASH (buffer[plen - 1])) buffer[plen++] = '/'; q = gnu_list_name->dir_contents; if (q) while (*q) { size_t qlen = strlen (q); if (*q == 'Y') { if (buffer_size < plen + qlen) { while ((buffer_size *=2 ) < plen + qlen) continue; buffer = xrealloc (buffer, buffer_size); } strcpy (buffer + plen, q + 1); dump_file (buffer, -1, (dev_t) 0); } q += qlen + 1; } } free (buffer); } else { while (p = name_next (1), p) if (!excluded_name (p)) dump_file (p, 1, (dev_t) 0); } write_eot (); close_archive (); if (listed_incremental_option) write_directory_file (); } /* Calculate the hash of a link. */ static unsigned hash_link (void const *entry, unsigned n_buckets) { struct link const *link = entry; return (uintmax_t) (link->dev ^ link->ino) % n_buckets; } /* Compare two links for equality. */ static bool compare_links (void const *entry1, void const *entry2) { struct link const *link1 = entry1; struct link const *link2 = entry2; return ((link1->dev ^ link2->dev) | (link1->ino ^ link2->ino)) == 0; } /* Dump a single file, recursing on directories. P is the file name to dump. TOP_LEVEL tells whether this is a top-level call; zero means no, positive means yes, and negative means an incremental dump. PARENT_DEVICE is the device of P's parent directory; it is examined only if TOP_LEVEL is zero. Set global CURRENT_STAT to stat output for this file. */ /* FIXME: One should make sure that for *every* path leading to setting exit_status to failure, a clear diagnostic has been issued. */ void dump_file (char *p, int top_level, dev_t parent_device) { union block *header; char type; union block *exhdr; char save_typeflag; time_t original_ctime; struct utimbuf restore_times; /* FIXME: `header' might be used uninitialized in this function. Reported by Bruno Haible. */ if (interactive_option && !confirm ("add", p)) return; if (deref_stat (dereference_option, p, ¤t_stat) != 0) { if (ignore_failed_read_option) stat_warn (p); else stat_error (p); return; } original_ctime = current_stat.st_ctime; restore_times.actime = current_stat.st_atime; restore_times.modtime = current_stat.st_mtime; #ifdef S_ISHIDDEN if (S_ISHIDDEN (current_stat.st_mode)) { char *new = (char *) alloca (strlen (p) + 2); if (new) { strcpy (new, p); strcat (new, "@"); p = new; } } #endif /* See if we want only new files, and check if this one is too old to put in the archive. */ if ((0 < top_level || !incremental_option) && !S_ISDIR (current_stat.st_mode) && current_stat.st_mtime < newer_mtime_option && (!after_date_option || current_stat.st_ctime < newer_ctime_option)) { if (0 < top_level) WARN ((0, 0, _("%s: file is unchanged; not dumped"), quotearg_colon (p))); /* FIXME: recheck this return. */ return; } #if !MSDOS /* See if we are trying to dump the archive. */ if (ar_dev && current_stat.st_dev == ar_dev && current_stat.st_ino == ar_ino) { WARN ((0, 0, _("%s: file is the archive; not dumped"), quotearg_colon (p))); return; } #endif if (S_ISDIR (current_stat.st_mode)) { char *directory; char const *entry; size_t entrylen; char *namebuf; size_t buflen; size_t len; dev_t our_device = current_stat.st_dev; errno = 0; directory = savedir (p); if (! directory) { if (ignore_failed_read_option) savedir_warn (p); else savedir_error (p); return; } /* Build new prototype name. Ensure exactly one trailing slash. */ len = strlen (p); buflen = len + NAME_FIELD_SIZE; namebuf = xmalloc (buflen + 1); memcpy (namebuf, p, len); while (len >= 1 && ISSLASH (namebuf[len - 1])) len--; namebuf[len++] = '/'; namebuf[len] = '\0'; if (! is_avoided_name (namebuf)) { /* The condition above used to be "archive_format != V7_FORMAT". GNU tar was not writing directory blocks at all. Daniel Trinkle writes: ``All old versions of tar I have ever seen have correctly archived an empty directory. The really old ones I checked included HP-UX 7 and Mt. Xinu More/BSD. There may be some subtle reason for the exclusion that I don't know, but the current behavior is broken.'' I do not know those subtle reasons either, so until these are reported (anew?), just allow directory blocks to be written even with old archives. */ current_stat.st_size = 0; /* force 0 size on dir */ /* FIXME: If people could really read standard archives, this should be: header = start_header (standard_option ? p : namebuf, ¤t_stat); but since they'd interpret DIRTYPE blocks as regular files, we'd better put the / on the name. */ header = start_header (namebuf, ¤t_stat); if (incremental_option) header->header.typeflag = GNUTYPE_DUMPDIR; else /* if (standard_option) */ header->header.typeflag = DIRTYPE; /* If we're gnudumping, we aren't done yet so don't close it. */ if (!incremental_option) finish_header (header); /* done with directory header */ } if (incremental_option && gnu_list_name->dir_contents) { off_t sizeleft; off_t totsize; size_t bufsize; union block *start; ssize_t count; const char *buffer, *p_buffer; buffer = gnu_list_name->dir_contents; /* FOO */ totsize = 0; for (p_buffer = buffer; p_buffer && *p_buffer;) { size_t tmp; tmp = strlen (p_buffer) + 1; totsize += tmp; p_buffer += tmp; } totsize++; OFF_TO_CHARS (totsize, header->header.size); finish_header (header); p_buffer = buffer; sizeleft = totsize; while (sizeleft > 0) { if (multi_volume_option) { assign_string (&save_name, p); save_sizeleft = sizeleft; save_totsize = totsize; } start = find_next_block (); bufsize = available_space_after (start); if (sizeleft < bufsize) { bufsize = sizeleft; count = bufsize % BLOCKSIZE; if (count) memset (start->buffer + sizeleft, 0, BLOCKSIZE - count); } memcpy (start->buffer, p_buffer, bufsize); sizeleft -= bufsize; p_buffer += bufsize; set_next_block_after (start + (bufsize - 1) / BLOCKSIZE); } if (multi_volume_option) assign_string (&save_name, 0); goto finish_dir; } /* See if we are about to recurse into a directory, and avoid doing so if the user wants that we do not descend into directories. */ if (! recursion_option) goto finish_dir; /* See if we are crossing from one file system to another, and avoid doing so if the user only wants to dump one file system. */ if (one_file_system_option && !top_level && parent_device != current_stat.st_dev) { if (verbose_option) WARN ((0, 0, _("%s: file is on a different filesystem; not dumped"), quotearg_colon (p))); goto finish_dir; } /* Now output all the files in the directory. */ /* FIXME: Should speed this up by cd-ing into the dir. */ for (entry = directory; (entrylen = strlen (entry)) != 0; entry += entrylen + 1) { if (buflen <= len + entrylen) { buflen = len + entrylen; namebuf = xrealloc (namebuf, buflen + 1); } strcpy (namebuf + len, entry); if (!excluded_name (namebuf)) dump_file (namebuf, 0, our_device); } finish_dir: free (directory); free (namebuf); if (atime_preserve_option) utime (p, &restore_times); return; } else if (is_avoided_name (p)) return; else { /* Check for multiple links. We maintain a table of all such files that we've written so far. Any time we see another, we check the table and avoid dumping the data again if we've done it once already. */ if (1 < current_stat.st_nlink) { static Hash_table *link_table; struct link *lp = xmalloc (sizeof *lp + strlen (p)); struct link *dup; lp->ino = current_stat.st_ino; lp->dev = current_stat.st_dev; strcpy (lp->name, p); if (! ((link_table || (link_table = hash_initialize (0, 0, hash_link, compare_links, 0))) && (dup = hash_insert (link_table, lp)))) xalloc_die (); if (dup != lp) { /* We found a link. */ char const *link_name = dup->name; free (lp); if (NAME_FIELD_SIZE <= strlen (link_name)) write_long (link_name, GNUTYPE_LONGLINK); assign_string (¤t_link_name, link_name); current_stat.st_size = 0; header = start_header (p, ¤t_stat); strncpy (header->header.linkname, link_name, NAME_FIELD_SIZE); /* Force null termination. */ header->header.linkname[NAME_FIELD_SIZE - 1] = 0; header->header.typeflag = LNKTYPE; finish_header (header); /* FIXME: Maybe remove from table after all links found? */ if (remove_files_option && unlink (p) != 0) unlink_error (p); /* We dumped it. */ return; } } /* This is not a link to a previously dumped file, so dump it. */ if (S_ISREG (current_stat.st_mode) || S_ISCTG (current_stat.st_mode)) { int f; /* file descriptor */ size_t bufsize; ssize_t count; off_t sizeleft; union block *start; int header_moved; char isextended = 0; int sparses = 0; header_moved = 0; if (sparse_option) { /* Check the size of the file against the number of blocks allocated for it, counting both data and indirect blocks. If there is a smaller number of blocks that would be necessary to accommodate a file of this size, this is safe to say that we have a sparse file: at least one of those blocks in the file is just a useless hole. For sparse files not having more hole blocks than indirect blocks, the sparseness will go undetected. */ /* Bruno Haible sent me these statistics for Linux. It seems that some filesystems count indirect blocks in st_blocks, while others do not seem to: minix-fs tar: size=7205, st_blocks=18 and ST_NBLOCKS=18 extfs tar: size=7205, st_blocks=18 and ST_NBLOCKS=18 ext2fs tar: size=7205, st_blocks=16 and ST_NBLOCKS=16 msdos-fs tar: size=7205, st_blocks=16 and ST_NBLOCKS=16 Dick Streefland reports the previous numbers as misleading, because ext2fs use 12 direct blocks, while minix-fs uses only 6 direct blocks. Dick gets: ext2 size=20480 ls listed blocks=21 minix size=20480 ls listed blocks=21 msdos size=20480 ls listed blocks=20 It seems that indirect blocks *are* included in st_blocks. The minix filesystem does not account for phantom blocks in st_blocks, so `du' and `ls -s' give wrong results. So, the --sparse option would not work on a minix filesystem. */ if (ST_NBLOCKS (current_stat) < (current_stat.st_size / ST_NBLOCKSIZE + (current_stat.st_size % ST_NBLOCKSIZE != 0))) { int counter; header = start_header (p, ¤t_stat); header->header.typeflag = GNUTYPE_SPARSE; header_moved = 1; /* Call the routine that figures out the layout of the sparse file in question. SPARSES is the index of the first unused element of the "sparsearray," i.e., the number of elements it needed to describe the file. */ sparses = deal_with_sparse (p, header); /* See if we'll need an extended header later. */ if (SPARSES_IN_OLDGNU_HEADER < sparses) header->oldgnu_header.isextended = 1; /* We store the "real" file size so we can show that in case someone wants to list the archive, i.e., tar tvf . It might be kind of disconcerting if the shrunken file size was the one that showed up. */ OFF_TO_CHARS (current_stat.st_size, header->oldgnu_header.realsize); /* This will be the new "size" of the file, i.e., the size of the file minus the blocks of holes that we're skipping over. */ current_stat.st_size = find_new_file_size (sparses); OFF_TO_CHARS (current_stat.st_size, header->header.size); for (counter = 0; counter < sparses && counter < SPARSES_IN_OLDGNU_HEADER; counter++) { OFF_TO_CHARS (sparsearray[counter].offset, header->oldgnu_header.sp[counter].offset); SIZE_TO_CHARS (sparsearray[counter].numbytes, header->oldgnu_header.sp[counter].numbytes); } } } sizeleft = current_stat.st_size; /* Don't bother opening empty, world readable files. Also do not open files when archive is meant for /dev/null. */ if (dev_null_output || (sizeleft == 0 && MODE_R == (MODE_R & current_stat.st_mode))) f = -1; else { f = open (p, O_RDONLY | O_BINARY); if (f < 0) { if (! top_level && errno == ENOENT) WARN ((0, 0, _("%s: File removed before we read it"), quotearg_colon (p))); else (ignore_failed_read_option ? open_warn : open_error) (p); return; } } /* If the file is sparse, we've already taken care of this. */ if (!header_moved) header = start_header (p, ¤t_stat); /* Mark contiguous files, if we support them. */ if (archive_format != V7_FORMAT && S_ISCTG (current_stat.st_mode)) header->header.typeflag = CONTTYPE; isextended = header->oldgnu_header.isextended; save_typeflag = header->header.typeflag; finish_header (header); if (isextended) { int sparses_emitted = SPARSES_IN_OLDGNU_HEADER; for (;;) { int i; exhdr = find_next_block (); memset (exhdr->buffer, 0, BLOCKSIZE); for (i = 0; (i < SPARSES_IN_SPARSE_HEADER && sparses_emitted + i < sparses); i++) { SIZE_TO_CHARS (sparsearray[sparses_emitted + i].numbytes, exhdr->sparse_header.sp[i].numbytes); OFF_TO_CHARS (sparsearray[sparses_emitted + i].offset, exhdr->sparse_header.sp[i].offset); } set_next_block_after (exhdr); sparses_emitted += i; if (sparses == sparses_emitted) break; exhdr->sparse_header.isextended = 1; } } if (save_typeflag == GNUTYPE_SPARSE) { if (f < 0 || finish_sparse_file (f, &sizeleft, current_stat.st_size, p)) goto padit; } else while (sizeleft > 0) { if (multi_volume_option) { assign_string (&save_name, p); save_sizeleft = sizeleft; save_totsize = current_stat.st_size; } start = find_next_block (); bufsize = available_space_after (start); if (sizeleft < bufsize) { /* Last read -- zero out area beyond. */ bufsize = sizeleft; count = bufsize % BLOCKSIZE; if (count) memset (start->buffer + sizeleft, 0, BLOCKSIZE - count); } if (f < 0) count = bufsize; else count = safe_read (f, start->buffer, bufsize); if (count < 0) { (ignore_failed_read_option ? read_warn_details : read_error_details) (p, current_stat.st_size - sizeleft, bufsize); goto padit; } sizeleft -= bufsize; /* This is nonportable (the type of set_next_block_after's arg). */ set_next_block_after (start + (bufsize - 1) / BLOCKSIZE); if (count != bufsize) { char buf[UINTMAX_STRSIZE_BOUND]; memset (start->buffer + count, 0, bufsize - count); WARN ((0, 0, _("%s: File shrank by %s bytes; padding with zeros"), quotearg_colon (p), STRINGIFY_BIGINT (sizeleft, buf))); if (! ignore_failed_read_option) exit_status = TAREXIT_FAILURE; goto padit; /* short read */ } } if (multi_volume_option) assign_string (&save_name, 0); if (f >= 0) { struct stat final_stat; if (fstat (f, &final_stat) != 0) { if (ignore_failed_read_option) stat_warn (p); else stat_error (p); } else if (final_stat.st_ctime != original_ctime) { char const *qp = quotearg_colon (p); WARN ((0, 0, _("%s: file changed as we read it"), qp)); if (! ignore_failed_read_option) exit_status = TAREXIT_FAILURE; } if (close (f) != 0) { if (ignore_failed_read_option) close_warn (p); else close_error (p); } if (atime_preserve_option) utime (p, &restore_times); } if (remove_files_option) { if (unlink (p) == -1) unlink_error (p); } return; /* File shrunk or gave error, pad out tape to match the size we specified in the header. */ padit: while (sizeleft > 0) { save_sizeleft = sizeleft; start = find_next_block (); memset (start->buffer, 0, BLOCKSIZE); set_next_block_after (start); sizeleft -= BLOCKSIZE; } if (multi_volume_option) assign_string (&save_name, 0); if (f >= 0) { close (f); if (atime_preserve_option) utime (p, &restore_times); } return; } #ifdef HAVE_READLINK else if (S_ISLNK (current_stat.st_mode)) { char *buffer; int size; size_t linklen = current_stat.st_size; if (linklen != current_stat.st_size || linklen + 1 == 0) xalloc_die (); buffer = (char *) alloca (linklen + 1); size = readlink (p, buffer, linklen + 1); if (size < 0) { if (ignore_failed_read_option) readlink_warn (p); else readlink_error (p); return; } buffer[size] = '\0'; if (size >= NAME_FIELD_SIZE) write_long (buffer, GNUTYPE_LONGLINK); assign_string (¤t_link_name, buffer); current_stat.st_size = 0; /* force 0 size on symlink */ header = start_header (p, ¤t_stat); strncpy (header->header.linkname, buffer, NAME_FIELD_SIZE); header->header.linkname[NAME_FIELD_SIZE - 1] = '\0'; header->header.typeflag = SYMTYPE; finish_header (header); /* nothing more to do to it */ if (remove_files_option) { if (unlink (p) == -1) unlink_error (p); } return; } #endif else if (S_ISCHR (current_stat.st_mode)) type = CHRTYPE; else if (S_ISBLK (current_stat.st_mode)) type = BLKTYPE; else if (S_ISFIFO (current_stat.st_mode)) type = FIFOTYPE; else if (S_ISSOCK (current_stat.st_mode)) { WARN ((0, 0, _("%s: socket ignored"), quotearg_colon (p))); return; } else if (S_ISDOOR (current_stat.st_mode)) { WARN ((0, 0, _("%s: door ignored"), quotearg_colon (p))); return; } else goto unknown; } if (archive_format == V7_FORMAT) goto unknown; current_stat.st_size = 0; /* force 0 size */ header = start_header (p, ¤t_stat); header->header.typeflag = type; if (type != FIFOTYPE) { MAJOR_TO_CHARS (major (current_stat.st_rdev), header->header.devmajor); MINOR_TO_CHARS (minor (current_stat.st_rdev), header->header.devminor); } finish_header (header); if (remove_files_option) { if (unlink (p) == -1) unlink_error (p); } return; unknown: WARN ((0, 0, _("%s: Unknown file type; file ignored"), quotearg_colon (p))); if (! ignore_failed_read_option) exit_status = TAREXIT_FAILURE; }