Merge branch '1952_tar'

* 1952_tar:
  tar: add support of extended headers.
  struct vfs_s_inode: add the 'user_data' member.
  tar: prepare to support the POSIX extended headers.
  tar: refactoring of archive reading.
  (tar_read_header): move entry/inode creation to new function tar_insert_entry().
  tar: use separate structure to store various file info.
  (tar_read_header): minor optimization.
  (tar_read_header): rename variable.
  (tar_find_next_block): rename from tar_get_next_block.
  src/vfs/tar/tar.c: remove period from error messages.
  (tar_read_header): rename variables.
  (tar_get_next_block): use file descriptor from archive descriptor.
  (tar_open_archive_int): return status of tar archive open
  src/vfs/tar/tar.c: clarify support of OLDGNU format.
  (tar_decode_header): do not decode size here.
  Ticket #1952: tar: support long file names in archive.
This commit is contained in:
Andrew Borodin 2023-05-20 19:45:28 +03:00
commit e5911c1ef5
8 changed files with 3388 additions and 437 deletions

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@ -255,6 +255,8 @@ AC_TYPE_MODE_T
gl_PROMOTED_TYPE_MODE_T
AC_TYPE_PID_T
AC_TYPE_UID_T
AC_CHECK_TYPE([major_t], [], [AC_DEFINE([major_t], [int], [Type of major device numbers.])])
AC_CHECK_TYPE([minor_t], [], [AC_DEFINE([minor_t], [int], [Type of minor device numbers.])])
AC_STRUCT_ST_BLOCKS
AC_CHECK_MEMBERS([struct stat.st_blksize, struct stat.st_rdev, struct stat.st_mtim])

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@ -95,6 +95,7 @@ struct vfs_s_inode
char *localname; /* Filename of local file, if we have one */
gint64 timestamp; /* Subclass specific */
off_t data_offset; /* Subclass specific */
void *user_data; /* Subclass specific */
};
/* Data associated with an open file */

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@ -4,4 +4,7 @@ AM_CPPFLAGS = $(GLIB_CFLAGS) -I$(top_srcdir)
noinst_LTLIBRARIES = libvfs-tar.la
libvfs_tar_la_SOURCES = \
tar-internal.c tar-internal.h \
tar-sparse.c \
tar-xheader.c \
tar.c tar.h

482
src/vfs/tar/tar-internal.c Normal file
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@ -0,0 +1,482 @@
/*
Virtual File System: GNU Tar file system.
Copyright (C) 2023
Free Software Foundation, Inc.
Written by:
Andrew Borodin <aborodin@vmail.ru>, 2023
This file is part of the Midnight Commander.
The Midnight Commander 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 3 of the License,
or (at your option) any later version.
The Midnight Commander 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, see <http://www.gnu.org/licenses/>.
*/
/**
* \file
* \brief Source: Virtual File System: GNU Tar file system
* \author Andrew Borodin
* \date 2022
*/
#include <config.h>
#include <ctype.h> /* isspace() */
#include <inttypes.h> /* uintmax_t */
#include <stdint.h> /* UINTMAX_MAX, etc */
#include "lib/global.h"
#include "lib/widget.h" /* message() */
#include "lib/vfs/vfs.h" /* mc_read() */
#include "tar-internal.h"
/*** global variables ****************************************************************************/
/*** file scope macro definitions ****************************************************************/
/* Log base 2 of common values. */
#define LG_8 3
#define LG_64 6
#define LG_256 8
/*** file scope type declarations ****************************************************************/
/*** forward declarations (file scope functions) *************************************************/
/*** file scope variables ************************************************************************/
/* Base 64 digits; see RFC 2045 Table 1. */
static char const base_64_digits[64] = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'
};
/* Table of base 64 digit values indexed by unsigned chars.
The value is 64 for unsigned chars that are not base 64 digits. */
static char base64_map[1 + (unsigned char) (-1)];
/* --------------------------------------------------------------------------------------------- */
/*** file scope functions ************************************************************************/
/* --------------------------------------------------------------------------------------------- */
static gboolean
tar_short_read (size_t status, tar_super_t * archive)
{
size_t left; /* bytes left */
char *more; /* pointer to next byte to read */
more = archive->record_start->buffer + status;
left = record_size - status;
while (left % BLOCKSIZE != 0 || (left != 0 && status != 0))
{
if (status != 0)
{
ssize_t r;
r = mc_read (archive->fd, more, left);
if (r == -1)
return FALSE;
status = (size_t) r;
}
if (status == 0)
break;
left -= status;
more += status;
}
record_end = archive->record_start + (record_size - left) / BLOCKSIZE;
return TRUE;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
tar_flush_read (tar_super_t * archive)
{
size_t status;
status = mc_read (archive->fd, archive->record_start->buffer, record_size);
if (status == record_size)
return TRUE;
return tar_short_read (status, archive);
}
/* --------------------------------------------------------------------------------------------- */
/** Flush the current buffer from the archive.
*/
static gboolean
tar_flush_archive (tar_super_t * archive)
{
record_start_block += record_end - archive->record_start;
current_block = archive->record_start;
record_end = archive->record_start + blocking_factor;
return tar_flush_read (archive);
}
/* --------------------------------------------------------------------------------------------- */
static off_t
tar_seek_archive (tar_super_t * archive, off_t size)
{
off_t start, offset;
off_t nrec, nblk;
off_t skipped;
skipped = (blocking_factor - (current_block - archive->record_start)) * BLOCKSIZE;
if (size <= skipped)
return 0;
/* Compute number of records to skip */
nrec = (size - skipped) / record_size;
if (nrec == 0)
return 0;
start = tar_current_block_ordinal (archive);
offset = mc_lseek (archive->fd, nrec * record_size, SEEK_CUR);
if (offset < 0)
return offset;
#if 0
if ((offset % record_size) != 0)
{
message (D_ERROR, MSG_ERROR, _("tar: mc_lseek not stopped at a record boundary"));
return -1;
}
#endif
/* Convert to number of records */
offset /= BLOCKSIZE;
/* Compute number of skipped blocks */
nblk = offset - start;
/* Update buffering info */
record_start_block = offset - blocking_factor;
current_block = record_end;
return nblk;
}
/* --------------------------------------------------------------------------------------------- */
/*** public functions ****************************************************************************/
/* --------------------------------------------------------------------------------------------- */
void
tar_base64_init (void)
{
size_t i;
memset (base64_map, 64, sizeof base64_map);
for (i = 0; i < 64; i++)
base64_map[(int) base_64_digits[i]] = i;
}
/* --------------------------------------------------------------------------------------------- */
void
tar_assign_string (char **string, char *value)
{
g_free (*string);
*string = value;
}
/* --------------------------------------------------------------------------------------------- */
void
tar_assign_string_dup (char **string, const char *value)
{
g_free (*string);
*string = g_strdup (value);
}
/* --------------------------------------------------------------------------------------------- */
void
tar_assign_string_dup_n (char **string, const char *value, size_t n)
{
g_free (*string);
*string = g_strndup (value, n);
}
/* --------------------------------------------------------------------------------------------- */
/**
* Convert buffer at @where0 of size @digs from external format to intmax_t.
* @digs must be positive.
* If @type is non-NULL, data are of type @type.
* The buffer must represent a value in the range -@minval through @maxval;
* if the mathematically correct result V would be greater than INTMAX_MAX,
* return a negative integer V such that (uintmax_t) V yields the correct result.
* If @octal_only, allow only octal numbers instead of the other GNU extensions.
*
* Result is -1 if the field is invalid.
*/
#if !(INTMAX_MAX <= UINTMAX_MAX && - (INTMAX_MIN + 1) <= UINTMAX_MAX)
#error "tar_from_header() internally represents intmax_t as uintmax_t + sign"
#endif
#if !(UINTMAX_MAX / 2 <= INTMAX_MAX)
#error "tar_from_header() returns intmax_t to represent uintmax_t"
#endif
intmax_t
tar_from_header (const char *where0, size_t digs, char const *type, intmax_t minval,
uintmax_t maxval, gboolean octal_only)
{
uintmax_t value = 0;
uintmax_t uminval = minval;
uintmax_t minus_minval = -uminval;
const char *where = where0;
char const *lim = where + digs;
gboolean negative = FALSE;
/* Accommodate buggy tar of unknown vintage, which outputs leading
NUL if the previous field overflows. */
if (*where == '\0')
where++;
/* Accommodate older tars, which output leading spaces. */
while (TRUE)
{
if (where == lim)
return (-1);
if (!isspace ((unsigned char) *where))
break;
where++;
}
if (isodigit (*where))
{
char const *where1 = where;
gboolean overflow = FALSE;
while (TRUE)
{
value += *where++ - '0';
if (where == lim || !isodigit (*where))
break;
overflow |= value != (value << LG_8 >> LG_8);
value <<= LG_8;
}
/* Parse the output of older, unportable tars, which generate
negative values in two's complement octal. If the leading
nonzero digit is 1, we can't recover the original value
reliably; so do this only if the digit is 2 or more. This
catches the common case of 32-bit negative time stamps. */
if ((overflow || maxval < value) && *where1 >= 2 && type != NULL)
{
/* Compute the negative of the input value, assuming two's complement. */
int digit;
digit = (*where1 - '0') | 4;
overflow = FALSE;
value = 0;
where = where1;
while (TRUE)
{
value += 7 - digit;
where++;
if (where == lim || !isodigit (*where))
break;
digit = *where - '0';
overflow |= value != (value << LG_8 >> LG_8);
value <<= LG_8;
}
value++;
overflow |= value == 0;
if (!overflow && value <= minus_minval)
negative = TRUE;
}
if (overflow)
return (-1);
}
else if (octal_only)
{
/* Suppress the following extensions. */
}
else if (*where == '-' || *where == '+')
{
/* Parse base-64 output produced only by tar test versions
1.13.6 (1999-08-11) through 1.13.11 (1999-08-23).
Support for this will be withdrawn in future tar releases. */
int dig;
negative = *where++ == '-';
while (where != lim && (dig = base64_map[(unsigned char) *where]) < 64)
{
if (value << LG_64 >> LG_64 != value)
return (-1);
value = (value << LG_64) | dig;
where++;
}
}
else if (where <= lim - 2 && (*where == '\200' /* positive base-256 */
|| *where == '\377' /* negative base-256 */ ))
{
/* Parse base-256 output. A nonnegative number N is
represented as (256**DIGS)/2 + N; a negative number -N is
represented as (256**DIGS) - N, i.e. as two's complement.
The representation guarantees that the leading bit is
always on, so that we don't confuse this format with the
others (assuming ASCII bytes of 8 bits or more). */
int signbit;
uintmax_t topbits;
signbit = *where & (1 << (LG_256 - 2));
topbits =
(((uintmax_t) - signbit) << (CHAR_BIT * sizeof (uintmax_t) - LG_256 - (LG_256 - 2)));
value = (*where++ & ((1 << (LG_256 - 2)) - 1)) - signbit;
while (TRUE)
{
value = (value << LG_256) + (unsigned char) *where++;
if (where == lim)
break;
if (((value << LG_256 >> LG_256) | topbits) != value)
return (-1);
}
negative = signbit != 0;
if (negative)
value = -value;
}
if (where != lim && *where != '\0' && !isspace ((unsigned char) *where))
return (-1);
if (value <= (negative ? minus_minval : maxval))
return tar_represent_uintmax (negative ? -value : value);
return (-1);
}
/* --------------------------------------------------------------------------------------------- */
off_t
off_from_header (const char *p, size_t s)
{
/* Negative offsets are not allowed in tar files, so invoke
from_header with minimum value 0, not TYPE_MINIMUM (off_t). */
return tar_from_header (p, s, "off_t", 0, TYPE_MAXIMUM (off_t), FALSE);
}
/* --------------------------------------------------------------------------------------------- */
/**
* Return the location of the next available input or output block.
* Return NULL for EOF.
*/
union block *
tar_find_next_block (tar_super_t * archive)
{
if (current_block == record_end)
{
if (hit_eof)
return NULL;
if (!tar_flush_archive (archive))
{
message (D_ERROR, MSG_ERROR, _("Inconsistent tar archive"));
return NULL;
}
if (current_block == record_end)
{
hit_eof = TRUE;
return NULL;
}
}
return current_block;
}
/* --------------------------------------------------------------------------------------------- */
/**
* Indicate that we have used all blocks up thru @block.
*/
gboolean
tar_set_next_block_after (union block * block)
{
while (block >= current_block)
current_block++;
/* Do *not* flush the archive here. If we do, the same argument to tar_set_next_block_after()
could mean the next block (if the input record is exactly one block long), which is not
what is intended. */
return !(current_block > record_end);
}
/* --------------------------------------------------------------------------------------------- */
/**
* Compute and return the block ordinal at current_block.
*/
off_t
tar_current_block_ordinal (const tar_super_t * archive)
{
return record_start_block + (current_block - archive->record_start);
}
/* --------------------------------------------------------------------------------------------- */
/**
* Skip over @size bytes of data in blocks in the archive.
*/
gboolean
tar_skip_file (tar_super_t * archive, off_t size)
{
union block *x;
off_t nblk;
nblk = tar_seek_archive (archive, size);
if (nblk >= 0)
size -= nblk * BLOCKSIZE;
while (size > 0)
{
x = tar_find_next_block (archive);
if (x == NULL)
return FALSE;
tar_set_next_block_after (x);
size -= BLOCKSIZE;
}
return TRUE;
}
/* --------------------------------------------------------------------------------------------- */

351
src/vfs/tar/tar-internal.h Normal file
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@ -0,0 +1,351 @@
#ifndef MC__VFS_TAR_INTERNAL_H
#define MC__VFS_TAR_INTERNAL_H
#include <inttypes.h> /* (u)intmax_t */
#include <limits.h> /* CHAR_BIT, INT_MAX, etc */
#include <sys/stat.h>
#include <sys/types.h>
#include "lib/vfs/xdirentry.h" /* vfs_s_super */
/*** typedefs(not structures) and defined constants **********************************************/
/* tar files are made in basic blocks of this size. */
#define BLOCKSIZE 512
#define DEFAULT_BLOCKING 20
/* Sparse files are not supported in POSIX ustar format. For sparse files
with a POSIX header, a GNU extra header is provided which holds overall
sparse information and a few sparse descriptors. When an old GNU header
replaces both the POSIX header and the GNU extra header, it holds some
sparse descriptors too. Whether POSIX or not, if more sparse descriptors
are still needed, they are put into as many successive sparse headers as
necessary. The following constants tell how many sparse descriptors fit
in each kind of header able to hold them. */
#define SPARSES_IN_EXTRA_HEADER 16
#define SPARSES_IN_OLDGNU_HEADER 4
#define SPARSES_IN_SPARSE_HEADER 21
#define SPARSES_IN_STAR_HEADER 4
#define SPARSES_IN_STAR_EXT_HEADER 21
/* *BEWARE* *BEWARE* *BEWARE* that the following information is still
boiling, and may change. Even if the OLDGNU format description should be
accurate, the so-called GNU format is not yet fully decided. It is
surely meant to use only extensions allowed by POSIX, but the sketch
below repeats some ugliness from the OLDGNU format, which should rather
go away. Sparse files should be saved in such a way that they do *not*
require two passes at archive creation time. Huge files get some POSIX
fields to overflow, alternate solutions have to be sought for this. */
/* This is a dir entry that contains the names of files that were in the
dir at the time the dump was made. */
#define GNUTYPE_DUMPDIR 'D'
/* Identifies the *next* file on the tape as having a long linkname. */
#define GNUTYPE_LONGLINK 'K'
/* Identifies the *next* file on the tape as having a long name. */
#define GNUTYPE_LONGNAME 'L'
/* Solaris extended header */
#define SOLARIS_XHDTYPE 'X'
#define GNUTYPE_SPARSE 'S'
/* These macros work even on ones'-complement hosts (!).
The extra casts work around some compiler bugs. */
#define TYPE_SIGNED(t) (!((t) 0 < (t) (-1)))
#define TYPE_MINIMUM(t) (TYPE_SIGNED (t) ? ~(t) 0 << (sizeof (t) * CHAR_BIT - 1) : (t) 0)
#define TYPE_MAXIMUM(t) (~(t) 0 - TYPE_MINIMUM (t))
#define OFF_FROM_HEADER(where) off_from_header (where, sizeof (where))
#define isodigit(c) ( ((c) >= '0') && ((c) <= '7') )
/*** enums ***************************************************************************************/
/*** structures declarations (and typedefs of structures)*****************************************/
/* *INDENT-OFF* */
/* POSIX header */
struct posix_header
{ /* byte offset */
char name[100]; /* 0 */
char mode[8]; /* 100 */
char uid[8]; /* 108 */
char gid[8]; /* 116 */
char size[12]; /* 124 */
char mtime[12]; /* 136 */
char chksum[8]; /* 148 */
char typeflag; /* 156 */
char linkname[100]; /* 157 */
char magic[6]; /* 257 */
char version[2]; /* 263 */
char uname[32]; /* 265 */
char gname[32]; /* 297 */
char devmajor[8]; /* 329 */
char devminor[8]; /* 337 */
char prefix[155]; /* 345 */
/* 500 */
};
/* Descriptor for a single file hole */
struct sparse
{ /* byte offset */
/* cppcheck-suppress unusedStructMember */
char offset[12]; /* 0 */
/* cppcheck-suppress unusedStructMember */
char numbytes[12]; /* 12 */
/* 24 */
};
/* Extension header for sparse files, used immediately after the GNU extra
header, and used only if all sparse information cannot fit into that
extra header. There might even be many such extension headers, one after
the other, until all sparse information has been recorded. */
struct sparse_header
{ /* byte offset */
struct sparse sp[SPARSES_IN_SPARSE_HEADER];
/* 0 */
char isextended; /* 504 */
/* 505 */
};
/* The old GNU format header conflicts with POSIX format in such a way that
POSIX archives may fool old GNU tar's, and POSIX tar's might well be
fooled by old GNU tar archives. An old GNU format header uses the space
used by the prefix field in a POSIX header, and cumulates information
normally found in a GNU extra header. With an old GNU tar header, we
never see any POSIX header nor GNU extra header. Supplementary sparse
headers are allowed, however. */
struct oldgnu_header
{ /* byte offset */
char unused_pad1[345]; /* 0 */
char atime[12]; /* 345 Incr. archive: atime of the file */
char ctime[12]; /* 357 Incr. archive: ctime of the file */
char offset[12]; /* 369 Multivolume archive: the offset of start of this volume */
char longnames[4]; /* 381 Not used */
char unused_pad2; /* 385 */
struct sparse sp[SPARSES_IN_OLDGNU_HEADER];
/* 386 */
char isextended; /* 482 Sparse file: Extension sparse header follows */
char realsize[12]; /* 483 Sparse file: Real size */
/* 495 */
};
/* J@"org Schilling star header */
struct star_header
{ /* byte offset */
char name[100]; /* 0 */
char mode[8]; /* 100 */
char uid[8]; /* 108 */
char gid[8]; /* 116 */
char size[12]; /* 124 */
char mtime[12]; /* 136 */
char chksum[8]; /* 148 */
char typeflag; /* 156 */
char linkname[100]; /* 157 */
char magic[6]; /* 257 */
char version[2]; /* 263 */
char uname[32]; /* 265 */
char gname[32]; /* 297 */
char devmajor[8]; /* 329 */
char devminor[8]; /* 337 */
char prefix[131]; /* 345 */
char atime[12]; /* 476 */
char ctime[12]; /* 488 */
/* 500 */
};
struct star_in_header
{
char fill[345]; /* 0 Everything that is before t_prefix */
char prefix[1]; /* 345 t_name prefix */
char fill2; /* 346 */
char fill3[8]; /* 347 */
char isextended; /* 355 */
struct sparse sp[SPARSES_IN_STAR_HEADER]; /* 356 */
char realsize[12]; /* 452 Actual size of the file */
char offset[12]; /* 464 Offset of multivolume contents */
char atime[12]; /* 476 */
char ctime[12]; /* 488 */
char mfill[8]; /* 500 */
char xmagic[4]; /* 508 "tar" */
};
struct star_ext_header
{
struct sparse sp[SPARSES_IN_STAR_EXT_HEADER];
char isextended;
};
/* *INDENT-ON* */
/* tar Header Block, overall structure */
union block
{
char buffer[BLOCKSIZE];
struct posix_header header;
struct star_header star_header;
struct oldgnu_header oldgnu_header;
struct sparse_header sparse_header;
struct star_in_header star_in_header;
struct star_ext_header star_ext_header;
};
/* Information about a sparse file */
struct sp_array
{
off_t offset; /* chunk offset in file */
off_t numbytes; /* length of chunk */
off_t arch_offset; /* chunk offset in archive */
};
enum dump_status
{
dump_status_ok,
dump_status_short,
dump_status_fail,
dump_status_not_implemented
};
enum archive_format
{
TAR_UNKNOWN = 0, /**< format to be decided later */
TAR_V7, /**< old V7 tar format */
TAR_OLDGNU, /**< GNU format as per before tar 1.12 */
TAR_USTAR, /**< POSIX.1-1988 (ustar) format */
TAR_POSIX, /**< POSIX.1-2001 format */
TAR_STAR, /**< star format defined in 1994 */
TAR_GNU /**< almost same as OLDGNU_FORMAT */
};
typedef struct
{
struct vfs_s_super base; /* base class */
int fd;
struct stat st;
enum archive_format type; /**< type of the archive */
union block *record_start; /**< start of record of archive */
} tar_super_t;
struct xheader
{
size_t size;
char *buffer;
};
struct tar_stat_info
{
char *orig_file_name; /**< name of file read from the archive header */
char *file_name; /**< name of file for the current archive entry after being normalized */
char *link_name; /**< name of link for the current archive entry */
#if 0
char *uname; /**< user name of owner */
char *gname; /**< group name of owner */
#endif
struct stat stat; /**< regular filesystem stat */
/* stat() doesn't always have access, data modification, and status
change times in a convenient form, so store them separately. */
struct timespec atime;
struct timespec mtime;
struct timespec ctime;
off_t archive_file_size; /**< size of file as stored in the archive.
Equals stat.st_size for non-sparse files */
gboolean is_sparse; /**< is the file sparse */
/* For sparse files */
unsigned int sparse_major;
unsigned int sparse_minor;
GArray *sparse_map; /**< array of struct sp_array */
off_t real_size; /**< real size of sparse file */
gboolean real_size_set; /**< TRUE when GNU.sparse.realsize is set in archived file */
gboolean sparse_name_done; /**< TRUE if 'GNU.sparse.name' header was processed pax header parsing.
Following 'path' header (lower priority) will be ignored. */
/* Extended headers */
struct xheader xhdr;
/* For dumpdirs */
gboolean is_dumpdir; /**< is the member a dumpdir? */
gboolean skipped; /**< the member contents is already read (for GNUTYPE_DUMPDIR) */
char *dumpdir; /**< contents of the dump directory */
};
/*** global variables defined in .c file *********************************************************/
extern const int blocking_factor;
extern const size_t record_size;
extern union block *record_end; /* last+1 block of archive record */
extern union block *current_block; /* current block of archive */
extern off_t record_start_block; /* block ordinal at record_start */
extern union block *current_header;
/* Have we hit EOF yet? */
extern gboolean hit_eof;
extern struct tar_stat_info current_stat_info;
/*** declarations of public functions ************************************************************/
/* tar-internal.c */
void tar_base64_init (void);
void tar_assign_string (char **string, char *value);
void tar_assign_string_dup (char **string, const char *value);
void tar_assign_string_dup_n (char **string, const char *value, size_t n);
intmax_t tar_from_header (const char *where0, size_t digs, char const *type, intmax_t minval,
uintmax_t maxval, gboolean octal_only);
off_t off_from_header (const char *p, size_t s);
union block *tar_find_next_block (tar_super_t * archive);
gboolean tar_set_next_block_after (union block *block);
off_t tar_current_block_ordinal (const tar_super_t * archive);
gboolean tar_skip_file (tar_super_t * archive, off_t size);
/* tar-sparse.c */
gboolean tar_sparse_member_p (tar_super_t * archive, struct tar_stat_info *st);
gboolean tar_sparse_fixup_header (tar_super_t * archive, struct tar_stat_info *st);
enum dump_status tar_sparse_skip_file (tar_super_t * archive, struct tar_stat_info *st);
/* tar-xheader.c */
gboolean tar_xheader_decode (struct tar_stat_info *st);
gboolean tar_xheader_read (tar_super_t * archive, struct xheader *xhdr, union block *header,
off_t size);
gboolean tar_xheader_decode_global (struct xheader *xhdr);
void tar_xheader_destroy (struct xheader *xhdr);
/*** inline functions ****************************************************************************/
/**
* Represent @n using a signed integer I such that (uintmax_t) I == @n.
With a good optimizing compiler, this is equivalent to (intmax_t) i
and requires zero machine instructions. */
#if !(UINTMAX_MAX / 2 <= INTMAX_MAX)
#error "tar_represent_uintmax() returns intmax_t to represent uintmax_t"
#endif
static inline intmax_t
tar_represent_uintmax (uintmax_t n)
{
intmax_t nd;
if (n <= INTMAX_MAX)
return n;
/* Avoid signed integer overflow on picky platforms. */
nd = n - INTMAX_MIN;
return nd + INTMAX_MIN;
}
#endif /* MC__VFS_TAR_INTERNAL_H */

763
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@ -0,0 +1,763 @@
/*
Virtual File System: GNU Tar file system.
Copyright (C) 2003-2023
Free Software Foundation, Inc.
Written by:
Andrew Borodin <aborodin@vmail.ru>, 2023
This file is part of the Midnight Commander.
The Midnight Commander 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 3 of the License,
or (at your option) any later version.
The Midnight Commander 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, see <http://www.gnu.org/licenses/>.
*/
/**
* \file
* \brief Source: Virtual File System: GNU Tar file system
*/
#include <config.h>
#include <ctype.h> /* isdigit() */
#include <errno.h>
#include <inttypes.h> /* uintmax_t */
#include "lib/global.h"
#include "tar-internal.h"
/* Old GNU Format.
The sparse file information is stored in the oldgnu_header in the following manner:
The header is marked with type 'S'. Its 'size' field contains the cumulative size
of all non-empty blocks of the file. The actual file size is stored in `realsize'
member of oldgnu_header.
The map of the file is stored in a list of 'struct sparse'. Each struct contains
offset to the block of data and its size (both as octal numbers). The first file
header contains at most 4 such structs (SPARSES_IN_OLDGNU_HEADER). If the map
contains more structs, then the field 'isextended' of the main header is set to
1 (binary) and the 'struct sparse_header' header follows, containing at most
21 following structs (SPARSES_IN_SPARSE_HEADER). If more structs follow, 'isextended'
field of the extended header is set and next next extension header follows, etc...
*/
/*** global variables ****************************************************************************/
/*** file scope macro definitions ****************************************************************/
/* The width in bits of the integer type or expression T.
Do not evaluate T. T must not be a bit-field expression.
Padding bits are not supported; this is checked at compile-time below. */
#define TYPE_WIDTH(t) (sizeof (t) * CHAR_BIT)
/* Bound on length of the string representing an unsigned integer
value representable in B bits. log10 (2.0) < 146/485. The
smallest value of B where this bound is not tight is 2621. */
#define INT_BITS_STRLEN_BOUND(b) (((b) * 146 + 484) / 485)
/* Does the __typeof__ keyword work? This could be done by
'configure', but for now it's easier to do it by hand. */
#if (2 <= __GNUC__ \
|| (4 <= __clang_major__) \
|| (1210 <= __IBMC__ && defined __IBM__TYPEOF__) \
|| (0x5110 <= __SUNPRO_C && !__STDC__))
#define _GL_HAVE___TYPEOF__ 1
#else
#define _GL_HAVE___TYPEOF__ 0
#endif
/* Return 1 if the integer type or expression T might be signed. Return 0
if it is definitely unsigned. T must not be a bit-field expression.
This macro does not evaluate its argument, and expands to an
integer constant expression. */
#if _GL_HAVE___TYPEOF__
#define _GL_SIGNED_TYPE_OR_EXPR(t) TYPE_SIGNED (__typeof__ (t))
#else
#define _GL_SIGNED_TYPE_OR_EXPR(t) 1
#endif
/* Return a value with the common real type of E and V and the value of V.
Do not evaluate E. */
#define _GL_INT_CONVERT(e, v) ((1 ? 0 : (e)) + (v))
/* Act like _GL_INT_CONVERT (E, -V) but work around a bug in IRIX 6.5 cc; see
<https://lists.gnu.org/r/bug-gnulib/2011-05/msg00406.html>. */
#define _GL_INT_NEGATE_CONVERT(e, v) ((1 ? 0 : (e)) - (v))
/* Return 1 if the real expression E, after promotion, has a
signed or floating type. Do not evaluate E. */
#define EXPR_SIGNED(e) (_GL_INT_NEGATE_CONVERT (e, 1) < 0)
#define _GL_SIGNED_INT_MAXIMUM(e) \
(((_GL_INT_CONVERT (e, 1) << (TYPE_WIDTH (+ (e)) - 2)) - 1) * 2 + 1)
/* The maximum and minimum values for the type of the expression E,
after integer promotion. E is not evaluated. */
#define _GL_INT_MINIMUM(e) \
(EXPR_SIGNED (e) \
? ~_GL_SIGNED_INT_MAXIMUM (e) \
: _GL_INT_CONVERT (e, 0))
#define _GL_INT_MAXIMUM(e) \
(EXPR_SIGNED (e) \
? _GL_SIGNED_INT_MAXIMUM (e) \
: _GL_INT_NEGATE_CONVERT (e, 1))
/* Return 1 if the expression A <op> B would overflow,
where OP_RESULT_OVERFLOW (A, B, MIN, MAX) does the actual test,
assuming MIN and MAX are the minimum and maximum for the result type.
Arguments should be free of side effects. */
#define _GL_BINARY_OP_OVERFLOW(a, b, op_result_overflow) \
op_result_overflow (a, b, \
_GL_INT_MINIMUM (_GL_INT_CONVERT (a, b)), \
_GL_INT_MAXIMUM (_GL_INT_CONVERT (a, b)))
#define INT_ADD_RANGE_OVERFLOW(a, b, min, max) \
((b) < 0 \
? (a) < (min) - (b) \
: (max) - (b) < (a))
/* True if __builtin_add_overflow_p (A, B, C) works, and similarly for
__builtin_sub_overflow_p and __builtin_mul_overflow_p. */
#if defined __clang__ || defined __ICC
/* Clang 11 lacks __builtin_mul_overflow_p, and even if it did it
would presumably run afoul of Clang bug 16404. ICC 2021.1's
__builtin_add_overflow_p etc. are not treated as integral constant
expressions even when all arguments are. */
#define _GL_HAS_BUILTIN_OVERFLOW_P 0
#elif defined __has_builtin
#define _GL_HAS_BUILTIN_OVERFLOW_P __has_builtin (__builtin_mul_overflow_p)
#else
#define _GL_HAS_BUILTIN_OVERFLOW_P (7 <= __GNUC__)
#endif
/* The _GL*_OVERFLOW macros have the same restrictions as the
*_RANGE_OVERFLOW macros, except that they do not assume that operands
(e.g., A and B) have the same type as MIN and MAX. Instead, they assume
that the result (e.g., A + B) has that type. */
#if _GL_HAS_BUILTIN_OVERFLOW_P
#define _GL_ADD_OVERFLOW(a, b, min, max) \
__builtin_add_overflow_p (a, b, (__typeof__ ((a) + (b))) 0)
#else
#define _GL_ADD_OVERFLOW(a, b, min, max) \
((min) < 0 ? INT_ADD_RANGE_OVERFLOW (a, b, min, max) \
: (a) < 0 ? (b) <= (a) + (b) \
: (b) < 0 ? (a) <= (a) + (b) \
: (a) + (b) < (b))
#endif
/* Bound on length of the string representing an integer type or expression T.
T must not be a bit-field expression.
Subtract 1 for the sign bit if T is signed, and then add 1 more for
a minus sign if needed.
Because _GL_SIGNED_TYPE_OR_EXPR sometimes returns 1 when its argument is
unsigned, this macro may overestimate the true bound by one byte when
applied to unsigned types of size 2, 4, 16, ... bytes. */
#define INT_STRLEN_BOUND(t) \
(INT_BITS_STRLEN_BOUND (TYPE_WIDTH (t) - _GL_SIGNED_TYPE_OR_EXPR (t)) \
+ _GL_SIGNED_TYPE_OR_EXPR (t))
/* Bound on buffer size needed to represent an integer type or expression T,
including the terminating null. T must not be a bit-field expression. */
#define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)
#define UINTMAX_STRSIZE_BOUND INT_BUFSIZE_BOUND (uintmax_t)
#define INT_ADD_OVERFLOW(a, b) \
_GL_BINARY_OP_OVERFLOW (a, b, _GL_ADD_OVERFLOW)
#define SPARSES_INIT_COUNT SPARSES_IN_SPARSE_HEADER
#define COPY_BUF(arch,b,buf,src) \
do \
{ \
char *endp = b->buffer + BLOCKSIZE; \
char *dst = buf; \
do \
{ \
if (dst == buf + UINTMAX_STRSIZE_BOUND - 1) \
/* numeric overflow in sparse archive member */ \
return FALSE; \
if (src == endp) \
{ \
tar_set_next_block_after (b); \
b = tar_find_next_block (arch); \
if (b == NULL) \
/* unexpected EOF in archive */ \
return FALSE; \
src = b->buffer; \
endp = b->buffer + BLOCKSIZE; \
} \
*dst = *src++; \
} \
while (*dst++ != '\n'); \
dst[-1] = '\0'; \
} \
while (FALSE)
/*** file scope type declarations ****************************************************************/
struct tar_sparse_file;
struct tar_sparse_optab
{
gboolean (*init) (struct tar_sparse_file * file);
gboolean (*done) (struct tar_sparse_file * file);
gboolean (*sparse_member_p) (struct tar_sparse_file * file);
gboolean (*fixup_header) (struct tar_sparse_file * file);
gboolean (*decode_header) (tar_super_t * archive, struct tar_sparse_file * file);
};
struct tar_sparse_file
{
int fd; /**< File descriptor */
off_t dumped_size; /**< Number of bytes actually written to the archive */
struct tar_stat_info *stat_info; /**< Information about the file */
struct tar_sparse_optab const *optab;
void *closure; /**< Any additional data optab calls might reqiure */
};
enum oldgnu_add_status
{
add_ok,
add_finish,
add_fail
};
/*** forward declarations (file scope functions) *************************************************/
static gboolean oldgnu_sparse_member_p (struct tar_sparse_file *file);
static gboolean oldgnu_fixup_header (struct tar_sparse_file *file);
static gboolean oldgnu_get_sparse_info (tar_super_t * archive, struct tar_sparse_file *file);
static gboolean star_sparse_member_p (struct tar_sparse_file *file);
static gboolean star_fixup_header (struct tar_sparse_file *file);
static gboolean star_get_sparse_info (tar_super_t * archive, struct tar_sparse_file *file);
static gboolean pax_sparse_member_p (struct tar_sparse_file *file);
static gboolean pax_decode_header (tar_super_t * archive, struct tar_sparse_file *file);
/*** file scope variables ************************************************************************/
/* *INDENT-OFF* */
static struct tar_sparse_optab const oldgnu_optab =
{
.init = NULL, /* No init function */
.done = NULL, /* No done function */
.sparse_member_p = oldgnu_sparse_member_p,
.fixup_header = oldgnu_fixup_header,
.decode_header = oldgnu_get_sparse_info
};
/* *INDENT-ON* */
/* *INDENT-OFF* */
static struct tar_sparse_optab const star_optab =
{
.init = NULL, /* No init function */
.done = NULL, /* No done function */
.sparse_member_p = star_sparse_member_p,
.fixup_header = star_fixup_header,
.decode_header = star_get_sparse_info
};
/* *INDENT-ON* */
/* GNU PAX sparse file format. There are several versions:
* 0.0
The initial version of sparse format used by tar 1.14-1.15.1.
The sparse file map is stored in x header:
GNU.sparse.size Real size of the stored file
GNU.sparse.numblocks Number of blocks in the sparse map repeat numblocks time
GNU.sparse.offset Offset of the next data block
GNU.sparse.numbytes Size of the next data block end repeat
This has been reported as conflicting with the POSIX specs. The reason is
that offsets and sizes of non-zero data blocks were stored in multiple instances
of GNU.sparse.offset/GNU.sparse.numbytes variables, whereas POSIX requires the
latest occurrence of the variable to override all previous occurrences.
To avoid this incompatibility two following versions were introduced.
* 0.1
Used by tar 1.15.2 -- 1.15.91 (alpha releases).
The sparse file map is stored in x header:
GNU.sparse.size Real size of the stored file
GNU.sparse.numblocks Number of blocks in the sparse map
GNU.sparse.map Map of non-null data chunks. A string consisting of comma-separated
values "offset,size[,offset,size]..."
The resulting GNU.sparse.map string can be *very* long. While POSIX does not impose
any limit on the length of a x header variable, this can confuse some tars.
* 1.0
Starting from this version, the exact sparse format version is specified explicitly
in the header using the following variables:
GNU.sparse.major Major version
GNU.sparse.minor Minor version
X header keeps the following variables:
GNU.sparse.name Real file name of the sparse file
GNU.sparse.realsize Real size of the stored file (corresponds to the old GNU.sparse.size
variable)
The name field of the ustar header is constructed using the pattern "%d/GNUSparseFile.%p/%f".
The sparse map itself is stored in the file data block, preceding the actual file data.
It consists of a series of octal numbers of arbitrary length, delimited by newlines.
The map is padded with nulls to the nearest block boundary.
The first number gives the number of entries in the map. Following are map entries, each one
consisting of two numbers giving the offset and size of the data block it describes.
The format is designed in such a way that non-posix aware tars and tars not supporting
GNU.sparse.* keywords will extract each sparse file in its condensed form with the file map
attached and will place it into a separate directory. Then, using a simple program it would be
possible to expand the file to its original form even without GNU tar.
Bu default, v.1.0 archives are created. To use other formats, --sparse-version option is provided.
Additionally, v.0.0 can be obtained by deleting GNU.sparse.map from 0.1 format:
--sparse-version 0.1 --pax-option delete=GNU.sparse.map
*/
static struct tar_sparse_optab const pax_optab = {
.init = NULL, /* No init function */
.done = NULL, /* No done function */
.sparse_member_p = pax_sparse_member_p,
.fixup_header = NULL, /* No fixup_header function */
.decode_header = pax_decode_header
};
/* --------------------------------------------------------------------------------------------- */
/*** file scope functions ************************************************************************/
/* --------------------------------------------------------------------------------------------- */
static gboolean
decode_num (uintmax_t * num, const char *arg, uintmax_t maxval)
{
uintmax_t u;
char *arg_lim;
if (!isdigit (*arg))
return FALSE;
errno = 0;
u = (uintmax_t) g_ascii_strtoll (arg, &arg_lim, 10);
if (!(u <= maxval && errno != ERANGE) || *arg_lim != '\0')
return FALSE;
*num = u;
return TRUE;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
sparse_select_optab (const tar_super_t * archive, struct tar_sparse_file *file)
{
switch (archive->type)
{
case TAR_V7:
case TAR_USTAR:
return FALSE;
case TAR_OLDGNU:
case TAR_GNU: /* FIXME: This one should disappear? */
file->optab = &oldgnu_optab;
break;
case TAR_POSIX:
file->optab = &pax_optab;
break;
case TAR_STAR:
file->optab = &star_optab;
break;
default:
return FALSE;
}
return TRUE;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
sparse_init (tar_super_t * archive, struct tar_sparse_file *file)
{
memset (file, 0, sizeof (*file));
if (!sparse_select_optab (archive, file))
return FALSE;
if (file->optab->init != NULL)
return file->optab->init (file);
return TRUE;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
sparse_done (struct tar_sparse_file *file)
{
if (file->optab->done != NULL)
return file->optab->done (file);
return TRUE;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
sparse_member_p (struct tar_sparse_file *file)
{
if (file->optab->sparse_member_p != NULL)
return file->optab->sparse_member_p (file);
return FALSE;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
sparse_fixup_header (struct tar_sparse_file *file)
{
if (file->optab->fixup_header != NULL)
return file->optab->fixup_header (file);
return TRUE;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
sparse_decode_header (tar_super_t * archive, struct tar_sparse_file *file)
{
if (file->optab->decode_header != NULL)
return file->optab->decode_header (archive, file);
return TRUE;
}
/* --------------------------------------------------------------------------------------------- */
static inline void
sparse_add_map (struct tar_stat_info *st, struct sp_array *sp)
{
if (st->sparse_map == NULL)
st->sparse_map = g_array_sized_new (FALSE, FALSE, sizeof (struct sp_array), 1);
g_array_append_val (st->sparse_map, *sp);
}
/* --------------------------------------------------------------------------------------------- */
/**
* Add a sparse item to the sparse file
*/
static enum oldgnu_add_status
oldgnu_add_sparse (struct tar_sparse_file *file, struct sparse *s)
{
struct sp_array sp;
if (s->numbytes[0] == '\0')
return add_finish;
sp.offset = OFF_FROM_HEADER (s->offset);
sp.numbytes = OFF_FROM_HEADER (s->numbytes);
if (sp.offset < 0 || sp.numbytes < 0
|| INT_ADD_OVERFLOW (sp.offset, sp.numbytes)
|| file->stat_info->stat.st_size < sp.offset + sp.numbytes
|| file->stat_info->archive_file_size < 0)
return add_fail;
sparse_add_map (file->stat_info, &sp);
return add_ok;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
oldgnu_sparse_member_p (struct tar_sparse_file *file)
{
(void) file;
return current_header->header.typeflag == GNUTYPE_SPARSE;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
oldgnu_fixup_header (struct tar_sparse_file *file)
{
/* NOTE! st_size was initialized from the header which actually contains archived size.
The following fixes it */
off_t realsize;
realsize = OFF_FROM_HEADER (current_header->oldgnu_header.realsize);
file->stat_info->archive_file_size = file->stat_info->stat.st_size;
file->stat_info->stat.st_size = MAX (0, realsize);
return (realsize >= 0);
}
/* --------------------------------------------------------------------------------------------- */
/**
* Convert old GNU format sparse data to internal representation.
*/
static gboolean
oldgnu_get_sparse_info (tar_super_t * archive, struct tar_sparse_file *file)
{
size_t i;
union block *h = current_header;
int ext_p;
enum oldgnu_add_status rc;
if (file->stat_info->sparse_map != NULL)
g_array_set_size (file->stat_info->sparse_map, 0);
for (i = 0; i < SPARSES_IN_OLDGNU_HEADER; i++)
{
rc = oldgnu_add_sparse (file, &h->oldgnu_header.sp[i]);
if (rc != add_ok)
break;
}
for (ext_p = h->oldgnu_header.isextended ? 1 : 0; rc == add_ok && ext_p != 0;
ext_p = h->sparse_header.isextended ? 1 : 0)
{
h = tar_find_next_block (archive);
if (h == NULL)
return FALSE;
tar_set_next_block_after (h);
for (i = 0; i < SPARSES_IN_SPARSE_HEADER && rc == add_ok; i++)
rc = oldgnu_add_sparse (file, &h->sparse_header.sp[i]);
}
return (rc != add_fail);
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
star_sparse_member_p (struct tar_sparse_file *file)
{
(void) file;
return current_header->header.typeflag == GNUTYPE_SPARSE;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
star_fixup_header (struct tar_sparse_file *file)
{
/* NOTE! st_size was initialized from the header which actually contains archived size.
The following fixes it */
off_t realsize;
realsize = OFF_FROM_HEADER (current_header->star_in_header.realsize);
file->stat_info->archive_file_size = file->stat_info->stat.st_size;
file->stat_info->stat.st_size = MAX (0, realsize);
return (realsize >= 0);
}
/* --------------------------------------------------------------------------------------------- */
/**
* Convert STAR format sparse data to internal representation
*/
static gboolean
star_get_sparse_info (tar_super_t * archive, struct tar_sparse_file *file)
{
size_t i;
union block *h = current_header;
int ext_p = 1;
enum oldgnu_add_status rc = add_ok;
if (file->stat_info->sparse_map != NULL)
g_array_set_size (file->stat_info->sparse_map, 0);
if (h->star_in_header.prefix[0] == '\0' && h->star_in_header.sp[0].offset[10] != '\0')
{
/* Old star format */
for (i = 0; i < SPARSES_IN_STAR_HEADER; i++)
{
rc = oldgnu_add_sparse (file, &h->star_in_header.sp[i]);
if (rc != add_ok)
break;
}
ext_p = h->star_in_header.isextended ? 1 : 0;
}
for (; rc == add_ok && ext_p != 0; ext_p = h->star_ext_header.isextended ? 1 : 0)
{
h = tar_find_next_block (archive);
if (h == NULL)
return FALSE;
tar_set_next_block_after (h);
for (i = 0; i < SPARSES_IN_STAR_EXT_HEADER && rc == add_ok; i++)
rc = oldgnu_add_sparse (file, &h->star_ext_header.sp[i]);
file->dumped_size += BLOCKSIZE;
}
return (rc != add_fail);
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
pax_sparse_member_p (struct tar_sparse_file *file)
{
return file->stat_info->sparse_map != NULL && file->stat_info->sparse_map->len > 0
&& file->stat_info->sparse_major > 0;
}
/* --------------------------------------------------------------------------------------------- */
static gboolean
pax_decode_header (tar_super_t * archive, struct tar_sparse_file *file)
{
if (file->stat_info->sparse_major > 0)
{
uintmax_t u;
char nbuf[UINTMAX_STRSIZE_BOUND];
union block *blk;
char *p;
size_t i;
off_t start;
start = tar_current_block_ordinal (archive);
tar_set_next_block_after (current_header);
blk = tar_find_next_block (archive);
if (blk == NULL)
/* unexpected EOF in archive */
return FALSE;
p = blk->buffer;
COPY_BUF (archive, blk, nbuf, p);
if (!decode_num (&u, nbuf, TYPE_MAXIMUM (size_t)))
{
/* malformed sparse archive member */
return FALSE;
}
if (file->stat_info->sparse_map == NULL)
file->stat_info->sparse_map =
g_array_sized_new (FALSE, FALSE, sizeof (struct sp_array), u);
else
g_array_set_size (file->stat_info->sparse_map, u);
for (i = 0; i < u; i++)
{
struct sp_array sp;
COPY_BUF (archive, blk, nbuf, p);
if (!decode_num (&u, nbuf, TYPE_MAXIMUM (off_t)))
{
/* malformed sparse archive member */
return FALSE;
}
sp.offset = u;
COPY_BUF (archive, blk, nbuf, p);
if (!decode_num (&u, nbuf, TYPE_MAXIMUM (size_t)) || INT_ADD_OVERFLOW (sp.offset, u)
|| file->stat_info->stat.st_size < sp.offset + u)
{
/* malformed sparse archive member */
return FALSE;
}
sp.numbytes = u;
sparse_add_map (file->stat_info, &sp);
}
tar_set_next_block_after (blk);
file->dumped_size += BLOCKSIZE * (tar_current_block_ordinal (archive) - start);
}
return TRUE;
}
/* --------------------------------------------------------------------------------------------- */
/*** public functions ****************************************************************************/
/* --------------------------------------------------------------------------------------------- */
gboolean
tar_sparse_member_p (tar_super_t * archive, struct tar_stat_info * st)
{
struct tar_sparse_file file;
if (!sparse_init (archive, &file))
return FALSE;
file.stat_info = st;
return sparse_member_p (&file);
}
/* --------------------------------------------------------------------------------------------- */
gboolean
tar_sparse_fixup_header (tar_super_t * archive, struct tar_stat_info * st)
{
struct tar_sparse_file file;
if (!sparse_init (archive, &file))
return FALSE;
file.stat_info = st;
return sparse_fixup_header (&file);
}
/* --------------------------------------------------------------------------------------------- */
enum dump_status
tar_sparse_skip_file (tar_super_t * archive, struct tar_stat_info *st)
{
gboolean rc = TRUE;
struct tar_sparse_file file;
if (!sparse_init (archive, &file))
return dump_status_not_implemented;
file.stat_info = st;
file.fd = -1;
rc = sparse_decode_header (archive, &file);
(void) tar_skip_file (archive, file.stat_info->archive_file_size - file.dumped_size);
return (sparse_done (&file) && rc) ? dump_status_ok : dump_status_short;
}
/* --------------------------------------------------------------------------------------------- */

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