On Tue, 9 May 2017 23:59:34 -0700 Zac Medico <zmed...@gentoo.org> wrote:
> Fix the lseek offset for the plain read/write loop to account > for buffered data that has not been written to to the output > file yet (due to previous interruption by EINTR). This code > only affects Linux 2.6.32 and earlier (newer kernels use > copy_file_range or sendfile). > > X-Gentoo-bug: 618086 > X-Gentoo-bug-url: https://bugs.gentoo.org/show_bug.cgi?id=618086 > --- > src/portage_util_file_copy_reflink_linux.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/src/portage_util_file_copy_reflink_linux.c > b/src/portage_util_file_copy_reflink_linux.c index 2fb17a0..4be9e05 > 100644 --- a/src/portage_util_file_copy_reflink_linux.c > +++ b/src/portage_util_file_copy_reflink_linux.c > @@ -323,12 +323,14 @@ _reflink_linux_file_copy(PyObject *self, > PyObject *args) if (buf == NULL) { > error = errno; > > - /* For the read call, the fd_in file offset must be > - * exactly equal to offset_out. Use lseek to ensure > - * correct state, in case an EINTR retry caused it to > - * get out of sync somewhow. > + /* For the read call, the fd_in file offset must be > exactly > + * equal to offset_out + buf_bytes, where buf_bytes > is the > + * amount of buffered data that has not been written > to > + * to the output file yet. Use lseek to ensure > correct state, > + * in case an EINTR retry caused it to get out of > sync > + * somewhow. > */ > - } else if (lseek(fd_in, offset_out, SEEK_SET) < 0) { > + } else if (lseek(fd_in, offset_out + buf_bytes, > SEEK_SET) < 0) { error = errno; > } else { > while (1) { > @@ -345,6 +347,7 @@ _reflink_linux_file_copy(PyObject *self, PyObject > *args) > } else if (buf_bytes < 0) { > error = errno; > + buf_bytes = 0; > break; > } > } looks fine :) -- Brian Dolbec <dolsen>
