From b35bd50ce62fbb98984560177198b94a7de46d00 Mon Sep 17 00:00:00 2001 From: Jim Meyering Date: Sat, 19 Aug 2006 14:01:29 +0000 Subject: * NEWS: Fix cp --sparse so that it preserves tail-end sparseness, even when the file's apparent size is not a multiple of its block size. * src/copy.c (copy_reg): Don't write a NUL before calling ftruncate. For some file sizes, writing that single byte would unnecessarily waste a few file blocks. That write may have been necessary in the early days of Linux, but now, removing it should be safe. Based on a patch by Alan Curry: * tests/cp/sparse: New test for the above. * tests/cp/Makefile.am (TESTS): Add sparse. * tests/sparse-file: New file, essence factored out of... * tests/du/8gb: ... here. Use the new script. --- ChangeLog | 15 ++++++++++++++ NEWS | 4 ++++ src/copy.c | 24 +++++++++++----------- tests/cp/Makefile.am | 1 + tests/cp/sparse | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++ tests/du/8gb | 16 ++------------- tests/sparse-file | 33 ++++++++++++++++++++++++++++++ 7 files changed, 124 insertions(+), 26 deletions(-) create mode 100755 tests/cp/sparse create mode 100644 tests/sparse-file diff --git a/ChangeLog b/ChangeLog index bbfb3a78f..04ae75989 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,18 @@ +2006-08-19 Jim Meyering + + * NEWS: Fix cp --sparse so that it preserves tail-end sparseness, even + when the file's apparent size is not a multiple of its block size. + * src/copy.c (copy_reg): Don't write a NUL before calling ftruncate. + For some file sizes, writing that single byte would unnecessarily + waste a few file blocks. That write may have been necessary in the + early days of Linux, but now, removing it should be safe. + Based on a patch by Alan Curry: + * tests/cp/sparse: New test for the above. + * tests/cp/Makefile.am (TESTS): Add sparse. + + * tests/sparse-file: New file, essence factored out of... + * tests/du/8gb: ... here. Use the new script. + 2006-08-18 Paul Eggert * src/system.h (select_plural): Reduce by 1000000, not 1000, since diff --git a/NEWS b/NEWS index 6882f75d6..6eeb49492 100644 --- a/NEWS +++ b/NEWS @@ -4,6 +4,10 @@ GNU coreutils NEWS -*- outline -*- ** Bug fixes + cp --sparse preserves sparseness at the end of a file, even when + the file's apparent size is not a multiple of its block size. + [introduced with the original design, in fileutils-4.0r, 2000-04-29] + df (with a command line argument) once again prints its header [introduced in coreutils-6.0] diff --git a/src/copy.c b/src/copy.c index 0a3f9e504..e11dd77f8 100644 --- a/src/copy.c +++ b/src/copy.c @@ -461,21 +461,21 @@ copy_reg (char const *src_name, char const *dst_name, } } - /* If the file ends with a `hole', something needs to be written at - the end. 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 - /* Write a null character and truncate it again. */ - if (full_write (dest_desc, "", 1) != 1 - || ftruncate (dest_desc, n_read_total) < 0) -#else - /* Seek backwards one character and write a null. */ - if (lseek (dest_desc, (off_t) -1, SEEK_CUR) < 0L - || full_write (dest_desc, "", 1) != 1) -#endif + 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; diff --git a/tests/cp/Makefile.am b/tests/cp/Makefile.am index 1a4aa84f4..5b4c23606 100644 --- a/tests/cp/Makefile.am +++ b/tests/cp/Makefile.am @@ -21,6 +21,7 @@ AUTOMAKE_OPTIONS = 1.1 gnits TESTS = \ + sparse \ link-no-deref \ cp-deref \ acl \ diff --git a/tests/cp/sparse b/tests/cp/sparse new file mode 100755 index 000000000..2842513b0 --- /dev/null +++ b/tests/cp/sparse @@ -0,0 +1,57 @@ +#!/bin/sh +# Test cp --sparse=always + +# Copyright (C) 2006 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 2 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, write to the Free Software +# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +# 02110-1301, USA. + +if test "$VERBOSE" = yes; then + set -x + cp --version +fi + +. $srcdir/../envvar-check +. $srcdir/../sparse-file + +pwd=`pwd` +t0=`echo "$0"|sed 's,.*/,,'`.tmp; tmp=$t0/$$ +trap 'status=$?; cd $pwd; chmod -R u+rwx $t0; rm -rf $t0 && exit $status' 0 +trap '(exit $?); exit $?' 1 2 13 15 + +framework_failure=0 +mkdir -p $tmp || framework_failure=1 +cd $tmp || framework_failure=1 + +# Create a sparse file. +# It has to be at least 128K in order to be sparse on some systems. +# Make its size one larger than 128K, in order to tickle the +# bug in coreutils-6.0. +size=`expr 128 \* 1024 + 1` +dd bs=1 seek=$size of=sparse < /dev/null 2> /dev/null || framework_failure=1 + +if test $framework_failure = 1; then + echo "$0: failure in testing framework" 1>&2 + (exit 1); exit 1 +fi + +fail=0 + +cp --sparse=always sparse copy || fail=1 + +# Ensure that the copy has the same block count as the original. +test `stat --printf %b sparse` = `stat --printf %b copy` || fail=1 + +(exit $fail); exit $fail diff --git a/tests/du/8gb b/tests/du/8gb index 036cb8699..0e7cfcdef 100755 --- a/tests/du/8gb +++ b/tests/du/8gb @@ -2,7 +2,7 @@ # Ensure that du does not rely on narrow types like size_t for # file sizes or sums. -# Copyright (C) 2003, 2005 Free Software Foundation, Inc. +# Copyright (C) 2003, 2005, 2006 Free Software Foundation, Inc. # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by @@ -25,6 +25,7 @@ if test "$VERBOSE" = yes; then fi . $srcdir/../envvar-check +. $srcdir/../sparse-file pwd=`pwd` t0=`echo "$0"|sed 's,.*/,,'`.tmp; tmp=$t0/$$ @@ -40,19 +41,6 @@ if test $framework_failure = 1; then (exit 1); exit 1 fi -# If this file system doesn't support sparse files, -# don't try to create a file that'd end up consuming 8GB. -# This happens on Darwin6.5 with a file system of type `hfs'. -# NTFS requires 128K before a hole appears in a sparse file. -dd bs=1 seek=128K of=t < /dev/null 2> /dev/null -set x `du -sk t` -if test "$2" -ge 128; then - echo "$0: skipping this test, since this file system doesn't support" 1>&2 - echo "$0: sparse files and this test requires a file with an apparent" 1>&2 - echo "$0: size of 8GB" 1>&2 - (exit 77); exit 77 -fi - dd bs=1 seek=8G of=big < /dev/null 2> /dev/null if test $? != 0; then echo "$0: cannot create a file large enough for this test; possibly" 1>&2 diff --git a/tests/sparse-file b/tests/sparse-file new file mode 100644 index 000000000..4d8c7a6bd --- /dev/null +++ b/tests/sparse-file @@ -0,0 +1,33 @@ +# -*- sh -*- +# Does the current (working-dir.) file system support sparse files? + +# Copyright (C) 2006 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 2 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, write to the Free Software +# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA +# 02110-1301, USA. + +# Test whether we can create a sparse file. +# For example, on Darwin6.5 with a file system of type hfs, it's not possible. +# NTFS requires 128K before a hole appears in a sparse file. +t=sparse.$$ +dd bs=1 seek=128K of=$t < /dev/null 2> /dev/null +set x `du -sk $t` +kb_size=$2 +rm -f $t +if test $kb_size -ge 128; then + echo "$0: skipping this test, since this file system doesn't support" \ + sparse files 1>&2 + (exit 77); exit 77 +fi -- cgit v1.2.3-54-g00ecf