-/* Functions for dealing with sparse files
+/* Functions for dealing with sparse files
- Copyright (C) 2003 Free Software Foundation, Inc.
+ Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc.
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
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. */
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
-#include "system.h"
+#include <system.h>
+#include <inttostr.h>
#include <quotearg.h>
#include "common.h"
struct tar_sparse_file;
+static bool sparse_select_optab (struct tar_sparse_file *file);
enum sparse_scan_state
{
{
bool (*init) (struct tar_sparse_file *);
bool (*done) (struct tar_sparse_file *);
+ bool (*sparse_member_p) (struct tar_sparse_file *);
bool (*dump_header) (struct tar_sparse_file *);
+ bool (*fixup_header) (struct tar_sparse_file *);
bool (*decode_header) (struct tar_sparse_file *);
bool (*scan_block) (struct tar_sparse_file *, enum sparse_scan_state,
void *);
- bool (*dump_region) (struct tar_sparse_file *, size_t index);
- bool (*extract_region) (struct tar_sparse_file *, size_t index);
+ bool (*dump_region) (struct tar_sparse_file *, size_t);
+ bool (*extract_region) (struct tar_sparse_file *, size_t);
};
struct tar_sparse_file
{
int fd; /* File descriptor */
- size_t dumped_size; /* Number of bytes actually written
+ bool seekable; /* Is fd seekable? */
+ off_t offset; /* Current offset in fd if seekable==false.
+ Otherwise unused */
+ 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 *optab;
+ struct tar_sparse_optab const *optab; /* Operation table */
void *closure; /* Any additional data optab calls might
- reqiure */
+ require */
};
+/* Dump zeros to file->fd until offset is reached. It is used instead of
+ lseek if the output file is not seekable */
+static bool
+dump_zeros (struct tar_sparse_file *file, off_t offset)
+{
+ static char const zero_buf[BLOCKSIZE];
+
+ if (offset < file->offset)
+ {
+ errno = EINVAL;
+ return false;
+ }
+
+ while (file->offset < offset)
+ {
+ size_t size = (BLOCKSIZE < offset - file->offset
+ ? BLOCKSIZE
+ : offset - file->offset);
+ ssize_t wrbytes;
+
+ wrbytes = write (file->fd, zero_buf, size);
+ if (wrbytes <= 0)
+ {
+ if (wrbytes == 0)
+ errno = EINVAL;
+ return false;
+ }
+ file->offset += wrbytes;
+ }
+
+ return true;
+}
+
+static bool
+tar_sparse_member_p (struct tar_sparse_file *file)
+{
+ if (file->optab->sparse_member_p)
+ return file->optab->sparse_member_p (file);
+ return false;
+}
+
static bool
tar_sparse_init (struct tar_sparse_file *file)
{
- file->dumped_size = 0;
+ memset (file, 0, sizeof *file);
+
+ if (!sparse_select_optab (file))
+ return false;
+
if (file->optab->init)
return file->optab->init (file);
+
return true;
}
}
static bool
-tar_sparse_dump_region (struct tar_sparse_file *file, size_t index)
+tar_sparse_dump_region (struct tar_sparse_file *file, size_t i)
{
if (file->optab->dump_region)
- return file->optab->dump_region (file, index);
+ return file->optab->dump_region (file, i);
return false;
}
static bool
-tar_sparse_extract_region (struct tar_sparse_file *file, size_t index)
+tar_sparse_extract_region (struct tar_sparse_file *file, size_t i)
{
if (file->optab->extract_region)
- return file->optab->extract_region (file, index);
+ return file->optab->extract_region (file, i);
return false;
}
{
if (file->optab->decode_header)
return file->optab->decode_header (file);
- return false;
+ return true;
+}
+
+static bool
+tar_sparse_fixup_header (struct tar_sparse_file *file)
+{
+ if (file->optab->fixup_header)
+ return file->optab->fixup_header (file);
+ return true;
}
\f
static bool
-lseek_or_error (struct tar_sparse_file *file, off_t offset, int whence)
+lseek_or_error (struct tar_sparse_file *file, off_t offset)
{
- if (lseek (file->fd, offset, whence) < 0)
+ if (file->seekable
+ ? lseek (file->fd, offset, SEEK_SET) < 0
+ : ! dump_zeros (file, offset))
{
seek_diag_details (file->stat_info->orig_file_name, offset);
return false;
it's made *entirely* of zeros, returning a 0 the instant it finds
something that is a nonzero, i.e., useful data. */
static bool
-zero_block_p (char *buffer, size_t size)
+zero_block_p (char const *buffer, size_t size)
{
while (size--)
if (*buffer++)
return true;
}
-#define clear_block(p) memset (p, 0, BLOCKSIZE);
-
-#define SPARSES_INIT_COUNT SPARSES_IN_SPARSE_HEADER
-
static void
-sparse_add_map (struct tar_sparse_file *file, struct sp_array *sp)
+sparse_add_map (struct tar_stat_info *st, struct sp_array const *sp)
{
- if (file->stat_info->sparse_map == NULL)
- {
- file->stat_info->sparse_map =
- xmalloc (SPARSES_INIT_COUNT * sizeof file->stat_info->sparse_map[0]);
- file->stat_info->sparse_map_size = SPARSES_INIT_COUNT;
- }
- else if (file->stat_info->sparse_map_avail == file->stat_info->sparse_map_size)
- {
- file->stat_info->sparse_map_size *= 2;
- file->stat_info->sparse_map =
- xrealloc (file->stat_info->sparse_map,
- file->stat_info->sparse_map_size
- * sizeof file->stat_info->sparse_map[0]);
- }
- file->stat_info->sparse_map[file->stat_info->sparse_map_avail++] = *sp;
+ struct sp_array *sparse_map = st->sparse_map;
+ size_t avail = st->sparse_map_avail;
+ if (avail == st->sparse_map_size)
+ st->sparse_map = sparse_map =
+ x2nrealloc (sparse_map, &st->sparse_map_size, sizeof *sparse_map);
+ sparse_map[avail] = *sp;
+ st->sparse_map_avail = avail + 1;
}
/* Scan the sparse file and create its map */
static bool
sparse_scan_file (struct tar_sparse_file *file)
{
- static char buffer[BLOCKSIZE];
+ struct tar_stat_info *st = file->stat_info;
+ int fd = file->fd;
+ char buffer[BLOCKSIZE];
size_t count;
- size_t offset = 0;
+ off_t offset = 0;
struct sp_array sp = {0, 0};
- if (!lseek_or_error (file, 0, SEEK_SET))
+ if (!lseek_or_error (file, 0))
return false;
- clear_block (buffer);
- file->stat_info->sparse_map_size = 0;
- file->stat_info->archive_file_size = 0;
+ st->archive_file_size = 0;
if (!tar_sparse_scan (file, scan_begin, NULL))
return false;
- while ((count = safe_read (file->fd, buffer, sizeof buffer)) > 0)
+ while ((count = safe_read (fd, buffer, sizeof buffer)) != 0
+ && count != SAFE_READ_ERROR)
{
- /* Analize the block */
+ /* Analyze the block. */
if (zero_block_p (buffer, count))
{
if (sp.numbytes)
{
- sparse_add_map (file, &sp);
+ sparse_add_map (st, &sp);
sp.numbytes = 0;
if (!tar_sparse_scan (file, scan_block, NULL))
return false;
if (sp.numbytes == 0)
sp.offset = offset;
sp.numbytes += count;
- file->stat_info->archive_file_size += count;
+ st->archive_file_size += count;
if (!tar_sparse_scan (file, scan_block, buffer))
return false;
}
-
+
offset += count;
- clear_block (buffer);
}
-
+
if (sp.numbytes == 0)
- {
- sp.offset = offset - 1;
- sp.numbytes = 1;
- }
- sparse_add_map (file, &sp);
- file->stat_info->archive_file_size += count;
+ sp.offset = offset;
+
+ sparse_add_map (st, &sp);
+ st->archive_file_size += count;
return tar_sparse_scan (file, scan_end, NULL);
}
-static struct tar_sparse_optab oldgnu_optab;
-static struct tar_sparse_optab star_optab;
-static struct tar_sparse_optab pax_optab;
+static struct tar_sparse_optab const oldgnu_optab;
+static struct tar_sparse_optab const star_optab;
+static struct tar_sparse_optab const pax_optab;
static bool
sparse_select_optab (struct tar_sparse_file *file)
case STAR_FORMAT:
file->optab = &star_optab;
break;
-
+
default:
return false;
}
}
static bool
-sparse_dump_region (struct tar_sparse_file *file, size_t index)
+sparse_dump_region (struct tar_sparse_file *file, size_t i)
{
union block *blk;
- off_t bytes_left = file->stat_info->sparse_map[index].numbytes;
-
- if (!lseek_or_error (file, file->stat_info->sparse_map[index].offset,
- SEEK_SET))
+ off_t bytes_left = file->stat_info->sparse_map[i].numbytes;
+
+ if (!lseek_or_error (file, file->stat_info->sparse_map[i].offset))
return false;
- do
+ while (bytes_left > 0)
{
size_t bufsize = (bytes_left > BLOCKSIZE) ? BLOCKSIZE : bytes_left;
- off_t bytes_read;
-
+ size_t bytes_read;
+
blk = find_next_block ();
- memset (blk->buffer, 0, BLOCKSIZE);
bytes_read = safe_read (file->fd, blk->buffer, bufsize);
- if (bytes_read < 0)
+ if (bytes_read == SAFE_READ_ERROR)
{
read_diag_details (file->stat_info->orig_file_name,
- file->stat_info->sparse_map[index].offset
- + file->stat_info->sparse_map[index].numbytes
- - bytes_left,
- bufsize);
+ (file->stat_info->sparse_map[i].offset
+ + file->stat_info->sparse_map[i].numbytes
+ - bytes_left),
+ bufsize);
return false;
}
+ memset (blk->buffer + bytes_read, 0, BLOCKSIZE - bytes_read);
bytes_left -= bytes_read;
file->dumped_size += bytes_read;
+ mv_size_left (file->stat_info->archive_file_size - file->dumped_size);
set_next_block_after (blk);
}
- while (bytes_left > 0);
+
return true;
}
static bool
-sparse_extract_region (struct tar_sparse_file *file, size_t index)
+sparse_extract_region (struct tar_sparse_file *file, size_t i)
{
size_t write_size;
-
- if (!lseek_or_error (file, file->stat_info->sparse_map[index].offset,
- SEEK_SET))
+
+ if (!lseek_or_error (file, file->stat_info->sparse_map[i].offset))
return false;
- write_size = file->stat_info->sparse_map[index].numbytes;
- while (write_size > 0)
+
+ write_size = file->stat_info->sparse_map[i].numbytes;
+
+ if (write_size == 0)
+ {
+ /* Last block of the file is a hole */
+ if (file->seekable && sys_truncate (file->fd))
+ truncate_warn (file->stat_info->orig_file_name);
+ }
+ else while (write_size > 0)
{
size_t count;
size_t wrbytes = (write_size > BLOCKSIZE) ? BLOCKSIZE : write_size;
count = full_write (file->fd, blk->buffer, wrbytes);
write_size -= count;
file->dumped_size += count;
+ mv_size_left (file->stat_info->archive_file_size - file->dumped_size);
+ file->offset += count;
if (count != wrbytes)
{
write_error_details (file->stat_info->orig_file_name,
/* Interface functions */
enum dump_status
-sparse_dump_file (int fd, struct tar_stat_info *stat)
+sparse_dump_file (int fd, struct tar_stat_info *st)
{
bool rc;
struct tar_sparse_file file;
- file.stat_info = stat;
- file.fd = fd;
-
- if (!sparse_select_optab (&file)
- || !tar_sparse_init (&file))
+ if (!tar_sparse_init (&file))
return dump_status_not_implemented;
+ file.stat_info = st;
+ file.fd = fd;
+ file.seekable = true; /* File *must* be seekable for dump to work */
+
rc = sparse_scan_file (&file);
if (rc && file.optab->dump_region)
{
{
size_t i;
+ mv_begin (file.stat_info);
for (i = 0; rc && i < file.stat_info->sparse_map_avail; i++)
rc = tar_sparse_dump_region (&file, i);
+ mv_end ();
}
}
- pad_archive(file.stat_info->archive_file_size - file.dumped_size);
+ pad_archive (file.stat_info->archive_file_size - file.dumped_size);
return (tar_sparse_done (&file) && rc) ? dump_status_ok : dump_status_short;
}
/* Returns true if the file represented by stat is a sparse one */
bool
-sparse_file_p (struct tar_stat_info *stat)
+sparse_file_p (struct tar_stat_info *st)
{
- return (ST_NBLOCKS (stat->stat)
- < (stat->stat.st_size / ST_NBLOCKSIZE
- + (stat->stat.st_size % ST_NBLOCKSIZE != 0)));
+ return (ST_NBLOCKS (st->stat)
+ < (st->stat.st_size / ST_NBLOCKSIZE
+ + (st->stat.st_size % ST_NBLOCKSIZE != 0)));
+}
+
+bool
+sparse_member_p (struct tar_stat_info *st)
+{
+ struct tar_sparse_file file;
+
+ if (!tar_sparse_init (&file))
+ return false;
+ file.stat_info = st;
+ return tar_sparse_member_p (&file);
+}
+
+bool
+sparse_fixup_header (struct tar_stat_info *st)
+{
+ struct tar_sparse_file file;
+
+ if (!tar_sparse_init (&file))
+ return false;
+ file.stat_info = st;
+ return tar_sparse_fixup_header (&file);
}
enum dump_status
-sparse_extract_file (int fd, struct tar_stat_info *stat, off_t *size)
+sparse_extract_file (int fd, struct tar_stat_info *st, off_t *size)
{
bool rc = true;
struct tar_sparse_file file;
size_t i;
-
- file.stat_info = stat;
- file.fd = fd;
- if (!sparse_select_optab (&file)
- || !tar_sparse_init (&file))
+ if (!tar_sparse_init (&file))
return dump_status_not_implemented;
+ file.stat_info = st;
+ file.fd = fd;
+ file.seekable = lseek (fd, 0, SEEK_SET) == 0;
+ file.offset = 0;
+
rc = tar_sparse_decode_header (&file);
for (i = 0; rc && i < file.stat_info->sparse_map_avail; i++)
rc = tar_sparse_extract_region (&file, i);
return (tar_sparse_done (&file) && rc) ? dump_status_ok : dump_status_short;
}
+enum dump_status
+sparse_skip_file (struct tar_stat_info *st)
+{
+ bool rc = true;
+ struct tar_sparse_file file;
+
+ if (!tar_sparse_init (&file))
+ return dump_status_not_implemented;
+
+ file.stat_info = st;
+ file.fd = -1;
+
+ rc = tar_sparse_decode_header (&file);
+ skip_file (file.stat_info->archive_file_size);
+ return (tar_sparse_done (&file) && rc) ? dump_status_ok : dump_status_short;
+}
+
\f
-static char diff_buffer[BLOCKSIZE];
-
static bool
check_sparse_region (struct tar_sparse_file *file, off_t beg, off_t end)
{
- if (!lseek_or_error (file, beg, SEEK_SET))
+ if (!lseek_or_error (file, beg))
return false;
-
+
while (beg < end)
{
size_t bytes_read;
- size_t rdsize = end - beg;
-
- if (rdsize > BLOCKSIZE)
- rdsize = BLOCKSIZE;
- clear_block (diff_buffer);
+ size_t rdsize = BLOCKSIZE < end - beg ? BLOCKSIZE : end - beg;
+ char diff_buffer[BLOCKSIZE];
+
bytes_read = safe_read (file->fd, diff_buffer, rdsize);
- if (bytes_read < 0)
+ if (bytes_read == SAFE_READ_ERROR)
{
read_diag_details (file->stat_info->orig_file_name,
beg,
}
if (!zero_block_p (diff_buffer, bytes_read))
{
+ char begbuf[INT_BUFSIZE_BOUND (off_t)];
report_difference (file->stat_info,
- _("File fragment at %lu is not a hole"), beg);
+ _("File fragment at %s is not a hole"),
+ offtostr (beg, begbuf));
return false;
}
}
static bool
-check_data_region (struct tar_sparse_file *file, size_t index)
+check_data_region (struct tar_sparse_file *file, size_t i)
{
size_t size_left;
-
- if (!lseek_or_error (file, file->stat_info->sparse_map[index].offset,
- SEEK_SET))
+
+ if (!lseek_or_error (file, file->stat_info->sparse_map[i].offset))
return false;
- size_left = file->stat_info->sparse_map[index].numbytes;
+ size_left = file->stat_info->sparse_map[i].numbytes;
+ mv_size_left (file->stat_info->archive_file_size - file->dumped_size);
+
while (size_left > 0)
{
size_t bytes_read;
size_t rdsize = (size_left > BLOCKSIZE) ? BLOCKSIZE : size_left;
-
+ char diff_buffer[BLOCKSIZE];
+
union block *blk = find_next_block ();
if (!blk)
{
}
set_next_block_after (blk);
bytes_read = safe_read (file->fd, diff_buffer, rdsize);
- if (bytes_read < 0)
+ if (bytes_read == SAFE_READ_ERROR)
{
read_diag_details (file->stat_info->orig_file_name,
- file->stat_info->sparse_map[index].offset
- + file->stat_info->sparse_map[index].numbytes
- - size_left,
+ (file->stat_info->sparse_map[i].offset
+ + file->stat_info->sparse_map[i].numbytes
+ - size_left),
rdsize);
return false;
}
file->dumped_size += bytes_read;
size_left -= bytes_read;
+ mv_size_left (file->stat_info->archive_file_size - file->dumped_size);
if (memcmp (blk->buffer, diff_buffer, rdsize))
{
report_difference (file->stat_info, _("Contents differ"));
}
bool
-sparse_diff_file (int fd, struct tar_stat_info *stat)
+sparse_diff_file (int fd, struct tar_stat_info *st)
{
bool rc = true;
struct tar_sparse_file file;
size_t i;
off_t offset = 0;
-
- file.stat_info = stat;
- file.fd = fd;
- if (!sparse_select_optab (&file)
- || !tar_sparse_init (&file))
+ if (!tar_sparse_init (&file))
return dump_status_not_implemented;
+ file.stat_info = st;
+ file.fd = fd;
+ file.seekable = true; /* File *must* be seekable for compare to work */
+
rc = tar_sparse_decode_header (&file);
+ mv_begin (st);
for (i = 0; rc && i < file.stat_info->sparse_map_avail; i++)
{
rc = check_sparse_region (&file,
offset, file.stat_info->sparse_map[i].offset)
- && check_data_region (&file, i);
+ && check_data_region (&file, i);
offset = file.stat_info->sparse_map[i].offset
+ file.stat_info->sparse_map[i].numbytes;
}
- if (rc)
+ if (!rc)
skip_file (file.stat_info->archive_file_size - file.dumped_size);
-
+ mv_end ();
+
tar_sparse_done (&file);
return rc;
}
-\f
+\f
/* 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
add_fail
};
+static bool
+oldgnu_sparse_member_p (struct tar_sparse_file *file __attribute__ ((unused)))
+{
+ return current_header->header.typeflag == GNUTYPE_SPARSE;
+}
+
/* Add a sparse item to the sparse file and its obstack */
-static enum oldgnu_add_status
+static enum oldgnu_add_status
oldgnu_add_sparse (struct tar_sparse_file *file, struct sparse *s)
{
struct sp_array sp;
|| file->stat_info->archive_file_size < 0)
return add_fail;
- sparse_add_map (file, &sp);
+ sparse_add_map (file->stat_info, &sp);
return add_ok;
}
-/* Convert old GNU format sparse data to internal representation
- FIXME: Clubbers current_header! */
+static bool
+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 */
+ file->stat_info->archive_file_size = file->stat_info->stat.st_size;
+ file->stat_info->stat.st_size =
+ OFF_FROM_HEADER (current_header->oldgnu_header.realsize);
+ return true;
+}
+
+/* Convert old GNU format sparse data to internal representation */
static bool
oldgnu_get_sparse_info (struct tar_sparse_file *file)
{
size_t i;
union block *h = current_header;
int ext_p;
- static enum oldgnu_add_status rc;
-
- /* FIXME: note this! st_size was initialized from the header
- which actually contains archived size. The following fixes it */
- file->stat_info->archive_file_size = file->stat_info->stat.st_size;
- file->stat_info->stat.st_size =
- OFF_FROM_HEADER (current_header->oldgnu_header.realsize);
-
- file->stat_info->sparse_map_size = 0;
+ enum oldgnu_add_status rc;
+
+ file->stat_info->sparse_map_avail = 0;
for (i = 0; i < SPARSES_IN_OLDGNU_HEADER; i++)
{
rc = oldgnu_add_sparse (file, &h->oldgnu_header.sp[i]);
off_t block_ordinal = current_block_ordinal ();
union block *blk;
size_t i;
-
+
blk = start_header (file->stat_info);
blk->header.typeflag = GNUTYPE_SPARSE;
if (file->stat_info->sparse_map_avail > SPARSES_IN_OLDGNU_HEADER)
SPARSES_IN_OLDGNU_HEADER);
blk->oldgnu_header.isextended = i < file->stat_info->sparse_map_avail;
finish_header (file->stat_info, blk, block_ordinal);
-
+
while (i < file->stat_info->sparse_map_avail)
{
blk = find_next_block ();
return true;
}
-static struct tar_sparse_optab oldgnu_optab = {
+static struct tar_sparse_optab const oldgnu_optab = {
NULL, /* No init function */
NULL, /* No done function */
+ oldgnu_sparse_member_p,
oldgnu_dump_header,
+ oldgnu_fixup_header,
oldgnu_get_sparse_info,
NULL, /* No scan_block function */
sparse_dump_region,
\f
/* Star */
-/* Convert STAR format sparse data to internal representation
- FIXME: Clubbers current_header! */
+static bool
+star_sparse_member_p (struct tar_sparse_file *file __attribute__ ((unused)))
+{
+ return current_header->header.typeflag == GNUTYPE_SPARSE;
+}
+
+static bool
+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 */
+ file->stat_info->archive_file_size = file->stat_info->stat.st_size;
+ file->stat_info->stat.st_size =
+ OFF_FROM_HEADER (current_header->star_in_header.realsize);
+ return true;
+}
+
+/* Convert STAR format sparse data to internal representation */
static bool
star_get_sparse_info (struct tar_sparse_file *file)
{
size_t i;
union block *h = current_header;
int ext_p;
- static enum oldgnu_add_status rc;
-
- /* FIXME: note this! st_size was initialized from the header
- which actually contains archived size. The following fixes it */
- file->stat_info->archive_file_size = file->stat_info->stat.st_size;
- file->stat_info->stat.st_size =
- OFF_FROM_HEADER (current_header->star_in_header.realsize);
-
- file->stat_info->sparse_map_size = 0;
+ enum oldgnu_add_status rc = add_ok;
+
+ file->stat_info->sparse_map_avail = 0;
if (h->star_in_header.prefix[0] == '\0'
&& h->star_in_header.sp[0].offset[10] != '\0')
}
-static struct tar_sparse_optab star_optab = {
+static struct tar_sparse_optab const star_optab = {
NULL, /* No init function */
NULL, /* No done function */
+ star_sparse_member_p,
NULL,
+ star_fixup_header,
star_get_sparse_info,
NULL, /* No scan_block function */
- NULL, /* No dump region function */
+ NULL, /* No dump region function */
sparse_extract_region,
};
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]..."
+
+ Tar versions 1.14-1.15.1 instead of the latter used:
+
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. However,
+ POSIX requires the latest occurrence of the variable to override all
+ previous occurrences.
+
+ To avoid this incompatibility new keyword GNU.sparse.map was introduced
+ in tar 1.15.2. Some people might still need the 1.14 way of handling
+ sparse files for the compatibility reasons: it can be achieved by
+ specifying `--pax-option delete=GNU.sparse.map' in the command line.
+
+ See FIXME-1.14-1.15.1-1.20, below.
*/
+static bool
+pax_sparse_member_p (struct tar_sparse_file *file)
+{
+ return file->stat_info->sparse_map_avail > 0;
+}
+
static bool
pax_dump_header (struct tar_sparse_file *file)
{
off_t block_ordinal = current_block_ordinal ();
union block *blk;
size_t i;
-
+ char nbuf[UINTMAX_STRSIZE_BOUND];
+ struct sp_array *map = file->stat_info->sparse_map;
+
/* Store the real file size */
xheader_store ("GNU.sparse.size", file->stat_info, NULL);
xheader_store ("GNU.sparse.numblocks", file->stat_info, NULL);
- for (i = 0; i < file->stat_info->sparse_map_avail; i++)
+
+ /* FIXME-1.14-1.15.1-1.20: See the comment above.
+ Starting with 1.17 this should display a warning about POSIX-incompatible
+ keywords being generated. In 1.20, the true branch of the if block below
+ will be removed and GNU.sparse.map will be marked in xhdr_tab as
+ protected. */
+
+ if (xheader_keyword_deleted_p ("GNU.sparse.map"))
{
- xheader_store ("GNU.sparse.offset", file->stat_info, &i);
- xheader_store ("GNU.sparse.numbytes", file->stat_info, &i);
+ for (i = 0; i < file->stat_info->sparse_map_avail; i++)
+ {
+ xheader_store ("GNU.sparse.offset", file->stat_info, &i);
+ xheader_store ("GNU.sparse.numbytes", file->stat_info, &i);
+ }
+ }
+ else
+ {
+ xheader_string_begin ();
+ for (i = 0; i < file->stat_info->sparse_map_avail; i++)
+ {
+ if (i)
+ xheader_string_add (",");
+ xheader_string_add (umaxtostr (map[i].offset, nbuf));
+ xheader_string_add (",");
+ xheader_string_add (umaxtostr (map[i].numbytes, nbuf));
+ }
+ xheader_string_end ("GNU.sparse.map");
}
-
blk = start_header (file->stat_info);
/* Store the effective (shrunken) file size */
OFF_TO_CHARS (file->stat_info->archive_file_size, blk->header.size);
return true;
}
-static bool
-pax_decode_header (struct tar_sparse_file *file)
-{
- /* Restore actual size */
- size_t s = file->stat_info->archive_file_size;
- file->stat_info->archive_file_size = file->stat_info->stat.st_size;
- file->stat_info->stat.st_size = s;
- return true;
-}
-
-static struct tar_sparse_optab pax_optab = {
+static struct tar_sparse_optab const pax_optab = {
NULL, /* No init function */
NULL, /* No done function */
+ pax_sparse_member_p,
pax_dump_header,
- pax_decode_header,
+ NULL, /* No decode_header function */
+ NULL, /* No fixup_header function */
NULL, /* No scan_block function */
sparse_dump_region,
sparse_extract_region,
};
-