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Diffstat (limited to 'contrib/tar/src/create.c')
| -rw-r--r-- | contrib/tar/src/create.c | 1550 |
1 files changed, 1550 insertions, 0 deletions
diff --git a/contrib/tar/src/create.c b/contrib/tar/src/create.c new file mode 100644 index 0000000..b3de6a8 --- /dev/null +++ b/contrib/tar/src/create.c @@ -0,0 +1,1550 @@ +/* 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 <pwd.h> +# include <grp.h> +#endif + +#if HAVE_UTIME_H +# include <utime.h> +#else +struct utimbuf + { + long actime; + long modtime; + }; +#endif + +#include <quotearg.h> + +#include "common.h" +#include <hash.h> + +#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 (offsetof (struct link, name) + + strlen (p) + 1); + 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 = relativize (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 + <file>. 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; +} |
