QFileSystemEngine/Unix: work around FreeBSD bug in copy_file_range(2)HEADdev

Amends commit 9b006eb91a612456f269161f79711e6fff3ccde0, which introduced
the use of this function. When I tested this with FreeBSD 14.2, this
code worked; now with 14.3 it doesn't, because on output the srcoffset
and dstoffset variables are still zero, in spite of having copied
content. That caused the copy_file_range() loop to copy the same files
over and over again, never exiting.

I've tracked this down to a change in 14.3[1] which showed that if both
inoffp and outoffp were non-NULL, it wouldn't update. FreeBSD
maintainers report this is already fixed[2] and will be made available
soon.

tst_qfile now passes again on FreeBSD.

strace output on Linux:
ioctl(5, BTRFS_IOC_CLONE or FICLONE, 4) = -1 EOPNOTSUPP (Operation not supported)
copy_file_range(4, [0], 5, NULL, 9223372036854775807, 0) = 13587
copy_file_range(4, [13587], 5, NULL, 9223372036854775807, 0) = 0

truss output on FreeBSD:
copy_file_range(0x4,0x32fb9588e360,0x5,0x0,0x7fffffffffffffff,0x0) = 624 (0x270)
copy_file_range(0x4,0x32fb9588e360,0x5,0x0,0x7fffffffffffffff,0x0) = 0 (0x0)

No changelog because the content is new in 6.10.

[1] https://github.com/freebsd/freebsd-src/commit/1d2fd8c9cf0fb796d8b7b7590288d3125398d445
[2] https://github.com/freebsd/freebsd-src/commit/4046ad6bb0ee542a42d89a48a7d6a56564ed7f33

Pick-to: 6.10
Fixes: QTBUG-138570
Change-Id: I31ddcefb63bb738f0cc0fffd75d9f68030952ed5
Reviewed-by: Ahmad Samir <[email protected]>

0 files changed, 0 insertions, 0 deletions