| # Ensure dd handles the 'nocache' flag | |
| # Copyright (C) 2011-2025 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 <https://www.gnu.org/licenses/>. | |
| . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src | |
| print_ver_ dd | |
| # This should not call posix_fadvise | |
| dd iflag=nocache oflag=nocache if=/dev/null of=/dev/null || fail=1 | |
| # We should get an error for trying to process a pipe | |
| dd count=0 | returns_ 1 dd iflag=nocache count=0 || fail=1 | |
| # O_DIRECT is orthogonal to drop cache so mutually exclusive | |
| returns_ 1 dd iflag=nocache,direct if=/dev/null || fail=1 | |
| # The rest ensure that the documented uses cases | |
| # proceed without error | |
| for f in ifile ofile; do | |
| dd if=/dev/zero of=$f conv=fdatasync count=100 || framework_failure_ | |
| done | |
| # Advise to drop cache for whole file | |
| if ! dd if=ifile iflag=nocache count=0 2>err; then | |
| # We could check for 'Operation not supported' in err here, | |
| # but that was seen to be brittle. HPUX returns ENOTTY for example. | |
| # So assume that if this basic operation fails, it's due to lack | |
| # of support by the system. | |
| warn_ 'skipping part; this file system lacks support for posix_fadvise()' | |
| skip=1 | |
| fi | |
| if test "$skip" != 1; then | |
| # Ensure drop cache for whole file | |
| dd of=ofile oflag=nocache conv=notrunc,fdatasync count=0 || fail=1 | |
| # Drop cache for part of file | |
| dd if=ifile iflag=nocache skip=10 count=10 of=/dev/null || fail=1 | |
| # Stream data just using readahead cache | |
| dd if=ifile of=ofile iflag=nocache oflag=nocache || fail=1 | |
| fi | |
| Exit $fail | |