int raw_export_start(RawExport *e, const char *path, int fd, ImportCompressType compress) {
_cleanup_close_ int sfd = -1, tfd = -1;
int r;
assert(e);
assert(path);
assert(fd >= 0);
assert(compress < _IMPORT_COMPRESS_TYPE_MAX);
assert(compress != IMPORT_COMPRESS_UNKNOWN);
if (e->output_fd >= 0)
return -EBUSY;
r = fd_nonblock(fd, true);
if (r < 0)
return r;
r = free_and_strdup(&e->path, path);
if (r < 0)
return r;
sfd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY);
if (sfd < 0)
return -errno;
if (fstat(sfd, &e->st) < 0)
return -errno;
r = stat_verify_regular(&e->st);
if (r < 0)
return r;
/* Try to take a reflink snapshot of the file, if we can t make the export atomic */
tfd = reflink_snapshot(sfd, path);
if (tfd >= 0)
e->input_fd = TAKE_FD(tfd);
else
e->input_fd = TAKE_FD(sfd);
r = import_compress_init(&e->compress, compress);
if (r < 0)
return r;
r = sd_event_add_io(e->event, &e->output_event_source, fd, EPOLLOUT, raw_export_on_output, e);
if (r == -EPERM) {
r = sd_event_add_defer(e->event, &e->output_event_source, raw_export_on_defer, e);
if (r < 0)
return r;
r = sd_event_source_set_enabled(e->output_event_source, SD_EVENT_ON);
}
if (r < 0)
return r;
e->output_fd = fd;
return r;
}
int tar_export_start(TarExport *e, const char *path, int fd, ImportCompressType compress) {
_cleanup_close_ int sfd = -1;
int r;
assert(e);
assert(path);
assert(fd >= 0);
assert(compress < _IMPORT_COMPRESS_TYPE_MAX);
assert(compress != IMPORT_COMPRESS_UNKNOWN);
if (e->output_fd >= 0)
return -EBUSY;
sfd = open(path, O_DIRECTORY|O_RDONLY|O_NOCTTY|O_CLOEXEC);
if (sfd < 0)
return -errno;
if (fstat(sfd, &e->st) < 0)
return -errno;
r = fd_nonblock(fd, true);
if (r < 0)
return r;
r = free_and_strdup(&e->path, path);
if (r < 0)
return r;
e->quota_referenced = (uint64_t) -1;
if (e->st.st_ino == 256) { /* might be a btrfs subvolume? */
BtrfsQuotaInfo q;
r = btrfs_subvol_get_subtree_quota_fd(sfd, 0, &q);
if (r >= 0)
e->quota_referenced = q.referenced;
e->temp_path = mfree(e->temp_path);
r = tempfn_random(path, NULL, &e->temp_path);
if (r < 0)
return r;
/* Let's try to make a snapshot, if we can, so that the export is atomic */
r = btrfs_subvol_snapshot_fd(sfd, e->temp_path, BTRFS_SNAPSHOT_READ_ONLY|BTRFS_SNAPSHOT_RECURSIVE);
if (r < 0) {
log_debug_errno(r, "Couldn't create snapshot %s of %s, not exporting atomically: %m", e->temp_path, path);
e->temp_path = mfree(e->temp_path);
}
}
r = import_compress_init(&e->compress, compress);
if (r < 0)
return r;
r = sd_event_add_io(e->event, &e->output_event_source, fd, EPOLLOUT, tar_export_on_output, e);
if (r == -EPERM) {
r = sd_event_add_defer(e->event, &e->output_event_source, tar_export_on_defer, e);
if (r < 0)
return r;
r = sd_event_source_set_enabled(e->output_event_source, SD_EVENT_ON);
}
if (r < 0)
return r;
e->tar_fd = import_fork_tar_c(e->temp_path ?: e->path, &e->tar_pid);
if (e->tar_fd < 0) {
e->output_event_source = sd_event_source_unref(e->output_event_source);
return e->tar_fd;
}
e->output_fd = fd;
return r;
}
