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cp --reflink: preserve attributes on cloned files if asked

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* src/copy.c (copy_reg): When cloning only skip the data copying
* tests/cp/reflink-perm: New test to check times and modes copied
* tests/Makefile.am: Reference the new test
* NEWS: Mention the fix
This commit is contained in:
Pádraig Brady 2009-08-29 00:45:15 +01:00
parent 72f98388c3
commit 9e59f8c47c
4 changed files with 187 additions and 137 deletions
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3
NEWS
View File

@ -9,6 +9,9 @@ GNU coreutils NEWS -*- outline -*-
and libraries tested at configure time.
[bug introduced in coreutils-7.5]
cp --reflink --preserve now preserves attributes when cloning a file.
[bug introduced in coreutils-7.5]
dd now returns non-zero status if it encountered a write error while
printing a summary to stderr.
[bug introduced in coreutils-6.11]

277
src/copy.c
View File

@ -490,6 +490,7 @@ copy_reg (char const *src_name, char const *dst_name,
struct stat sb;
struct stat src_open_sb;
bool return_val = true;
bool data_copy_required = true;
source_desc = open (src_name,
(O_RDONLY | O_BINARY
@ -644,175 +645,177 @@ copy_reg (char const *src_name, char const *dst_name,
{
error (0, errno, _("failed to clone %s"), quote (dst_name));
return_val = false;
goto close_src_and_dst_desc;
}
goto close_src_and_dst_desc;
data_copy_required = false;
}
}
{
typedef uintptr_t word;
off_t n_read_total = 0;
if (data_copy_required)
{
typedef uintptr_t word;
off_t n_read_total = 0;
/* Choose a suitable buffer size; it may be adjusted later. */
size_t buf_alignment = lcm (getpagesize (), sizeof (word));
size_t buf_alignment_slop = sizeof (word) + buf_alignment - 1;
size_t buf_size = io_blksize (sb);
/* Choose a suitable buffer size; it may be adjusted later. */
size_t buf_alignment = lcm (getpagesize (), sizeof (word));
size_t buf_alignment_slop = sizeof (word) + buf_alignment - 1;
size_t buf_size = io_blksize (sb);
/* Deal with sparse files. */
bool last_write_made_hole = false;
bool make_holes = false;
/* Deal with sparse files. */
bool last_write_made_hole = false;
bool make_holes = false;
if (S_ISREG (sb.st_mode))
{
/* Even with --sparse=always, try to create holes only
if the destination is a regular file. */
if (x->sparse_mode == SPARSE_ALWAYS)
make_holes = true;
if (S_ISREG (sb.st_mode))
{
/* Even with --sparse=always, try to create holes only
if the destination is a regular file. */
if (x->sparse_mode == SPARSE_ALWAYS)
make_holes = true;
#if HAVE_STRUCT_STAT_ST_BLOCKS
/* Use a heuristic to determine whether SRC_NAME contains any sparse
blocks. If the file has fewer blocks than would normally be
needed for a file of its size, then at least one of the blocks in
the file is a hole. */
if (x->sparse_mode == SPARSE_AUTO && S_ISREG (src_open_sb.st_mode)
&& ST_NBLOCKS (src_open_sb) < src_open_sb.st_size / ST_NBLOCKSIZE)
make_holes = true;
/* Use a heuristic to determine whether SRC_NAME contains any sparse
blocks. If the file has fewer blocks than would normally be
needed for a file of its size, then at least one of the blocks in
the file is a hole. */
if (x->sparse_mode == SPARSE_AUTO && S_ISREG (src_open_sb.st_mode)
&& ST_NBLOCKS (src_open_sb) < src_open_sb.st_size / ST_NBLOCKSIZE)
make_holes = true;
#endif
}
}
/* If not making a sparse file, try to use a more-efficient
buffer size. */
if (! make_holes)
{
/* Compute the least common multiple of the input and output
buffer sizes, adjusting for outlandish values. */
size_t blcm_max = MIN (SIZE_MAX, SSIZE_MAX) - buf_alignment_slop;
size_t blcm = buffer_lcm (io_blksize (src_open_sb), buf_size,
blcm_max);
/* If not making a sparse file, try to use a more-efficient
buffer size. */
if (! make_holes)
{
/* Compute the least common multiple of the input and output
buffer sizes, adjusting for outlandish values. */
size_t blcm_max = MIN (SIZE_MAX, SSIZE_MAX) - buf_alignment_slop;
size_t blcm = buffer_lcm (io_blksize (src_open_sb), buf_size,
blcm_max);
/* Do not bother with a buffer larger than the input file, plus one
byte to make sure the file has not grown while reading it. */
if (S_ISREG (src_open_sb.st_mode) && src_open_sb.st_size < buf_size)
buf_size = src_open_sb.st_size + 1;
/* Do not bother with a buffer larger than the input file, plus one
byte to make sure the file has not grown while reading it. */
if (S_ISREG (src_open_sb.st_mode) && src_open_sb.st_size < buf_size)
buf_size = src_open_sb.st_size + 1;
/* However, stick with a block size that is a positive multiple of
blcm, overriding the above adjustments. Watch out for
overflow. */
buf_size += blcm - 1;
buf_size -= buf_size % blcm;
if (buf_size == 0 || blcm_max < buf_size)
buf_size = blcm;
}
/* However, stick with a block size that is a positive multiple of
blcm, overriding the above adjustments. Watch out for
overflow. */
buf_size += blcm - 1;
buf_size -= buf_size % blcm;
if (buf_size == 0 || blcm_max < buf_size)
buf_size = blcm;
}
/* Make a buffer with space for a sentinel at the end. */
buf_alloc = xmalloc (buf_size + buf_alignment_slop);
buf = ptr_align (buf_alloc, buf_alignment);
/* Make a buffer with space for a sentinel at the end. */
buf_alloc = xmalloc (buf_size + buf_alignment_slop);
buf = ptr_align (buf_alloc, buf_alignment);
for (;;)
{
word *wp = NULL;
for (;;)
{
word *wp = NULL;
ssize_t n_read = read (source_desc, buf, buf_size);
if (n_read < 0)
{
ssize_t n_read = read (source_desc, buf, buf_size);
if (n_read < 0)
{
#ifdef EINTR
if (errno == EINTR)
continue;
if (errno == EINTR)
continue;
#endif
error (0, errno, _("reading %s"), quote (src_name));
return_val = false;
goto close_src_and_dst_desc;
}
if (n_read == 0)
break;
error (0, errno, _("reading %s"), quote (src_name));
return_val = false;
goto close_src_and_dst_desc;
}
if (n_read == 0)
break;
n_read_total += n_read;
n_read_total += n_read;
if (make_holes)
{
char *cp;
if (make_holes)
{
char *cp;
/* Sentinel to stop loop. */
buf[n_read] = '\1';
/* Sentinel to stop loop. */
buf[n_read] = '\1';
#ifdef lint
/* Usually, buf[n_read] is not the byte just before a "word"
(aka uintptr_t) boundary. In that case, the word-oriented
test below (*wp++ == 0) would read some uninitialized bytes
after the sentinel. To avoid false-positive reports about
this condition (e.g., from a tool like valgrind), set the
remaining bytes -- to any value. */
memset (buf + n_read + 1, 0, sizeof (word) - 1);
/* Usually, buf[n_read] is not the byte just before a "word"
(aka uintptr_t) boundary. In that case, the word-oriented
test below (*wp++ == 0) would read some uninitialized bytes
after the sentinel. To avoid false-positive reports about
this condition (e.g., from a tool like valgrind), set the
remaining bytes -- to any value. */
memset (buf + n_read + 1, 0, sizeof (word) - 1);
#endif
/* Find first nonzero *word*, or the word with the sentinel. */
/* Find first nonzero *word*, or the word with the sentinel. */
wp = (word *) buf;
while (*wp++ == 0)
continue;
wp = (word *) buf;
while (*wp++ == 0)
continue;
/* Find the first nonzero *byte*, or the sentinel. */
/* Find the first nonzero *byte*, or the sentinel. */
cp = (char *) (wp - 1);
while (*cp++ == 0)
continue;
cp = (char *) (wp - 1);
while (*cp++ == 0)
continue;
if (cp <= buf + n_read)
/* Clear to indicate that a normal write is needed. */
wp = NULL;
else
{
/* We found the sentinel, so the whole input block was zero.
Make a hole. */
if (lseek (dest_desc, n_read, SEEK_CUR) < 0)
{
error (0, errno, _("cannot lseek %s"), quote (dst_name));
return_val = false;
goto close_src_and_dst_desc;
}
last_write_made_hole = true;
}
}
if (cp <= buf + n_read)
/* Clear to indicate that a normal write is needed. */
wp = NULL;
else
{
/* We found the sentinel, so the whole input block was zero.
Make a hole. */
if (lseek (dest_desc, n_read, SEEK_CUR) < 0)
{
error (0, errno, _("cannot lseek %s"), quote (dst_name));
return_val = false;
goto close_src_and_dst_desc;
}
last_write_made_hole = true;
}
}
if (!wp)
{
size_t n = n_read;
if (full_write (dest_desc, buf, n) != n)
{
error (0, errno, _("writing %s"), quote (dst_name));
return_val = false;
goto close_src_and_dst_desc;
}
last_write_made_hole = false;
if (!wp)
{
size_t n = n_read;
if (full_write (dest_desc, buf, n) != n)
{
error (0, errno, _("writing %s"), quote (dst_name));
return_val = false;
goto close_src_and_dst_desc;
}
last_write_made_hole = false;
/* It is tempting to return early here upon a short read from a
regular file. That would save the final read syscall for each
file. Unfortunately that doesn't work for certain files in
/proc with linux kernels from at least 2.6.9 .. 2.6.29. */
}
}
/* It is tempting to return early here upon a short read from a
regular file. That would save the final read syscall for each
file. Unfortunately that doesn't work for certain files in
/proc with linux kernels from at least 2.6.9 .. 2.6.29. */
}
}
/* If the file ends with a `hole', we need to do something to record
the length of the file. On modern systems, calling ftruncate does
the job. On systems without native ftruncate support, we have to
write a byte at the ending position. Otherwise the kernel would
truncate the file at the end of the last write operation. */
/* If the file ends with a `hole', we need to do something to record
the length of the file. On modern systems, calling ftruncate does
the job. On systems without native ftruncate support, we have to
write a byte at the ending position. Otherwise the kernel would
truncate the file at the end of the last write operation. */
if (last_write_made_hole)
{
if (HAVE_FTRUNCATE
? /* ftruncate sets the file size,
so there is no need for a write. */
ftruncate (dest_desc, n_read_total) < 0
: /* Seek backwards one character and write a null. */
(lseek (dest_desc, (off_t) -1, SEEK_CUR) < 0L
|| full_write (dest_desc, "", 1) != 1))
{
error (0, errno, _("writing %s"), quote (dst_name));
return_val = false;
goto close_src_and_dst_desc;
}
}
}
if (last_write_made_hole)
{
if (HAVE_FTRUNCATE
? /* ftruncate sets the file size,
so there is no need for a write. */
ftruncate (dest_desc, n_read_total) < 0
: /* Seek backwards one character and write a null. */
(lseek (dest_desc, (off_t) -1, SEEK_CUR) < 0L
|| full_write (dest_desc, "", 1) != 1))
{
error (0, errno, _("writing %s"), quote (dst_name));
return_val = false;
goto close_src_and_dst_desc;
}
}
}
if (x->preserve_timestamps)
{

1
tests/Makefile.am
View File

@ -292,6 +292,7 @@ TESTS = \
cp/proc-zero-len \
cp/r-vs-symlink \
cp/reflink-auto \
cp/reflink-perm \
cp/same-file \
cp/slink-2-slink \
cp/sparse \

43
tests/cp/reflink-perm Executable file
View File

@ -0,0 +1,43 @@
#!/bin/sh
# Test cp --reflink copies permissions
# Copyright (C) 2009 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 Free Software Foundation, either version 3 of the License, 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, see <http://www.gnu.org/licenses/>.
if test "$VERBOSE" = yes; then
set -x
cp --version
fi
. $srcdir/test-lib.sh
fail=0
: > time_check
: > file
ts='2009-08-28 19:00'
touch -d "$ts" file || framework_failure
test time_check -nt file || skip_test_ "The system clock is wrong"
chmod a=rwx file || framework_failure
umask 077
cp --reflink=auto --preserve file copy || fail=1
mode=$(stat --printf "%A" copy)
test "$mode" = "-rwxrwxrwx" || fail=1
test copy -nt file && fail=1
Exit $fail