/**
* Get the layout for the file with FID \a fidstr in filesystem \a lustre_dir.
*
* \param[in] lustre_dir path within Lustre filesystem containing \a fid
* \param[in] fid Lustre identifier of file to get layout for
*
* \retval valid llapi_layout pointer on success
* \retval NULL if an error occurs
*/
struct llapi_layout *llapi_layout_get_by_fid(const char *lustre_dir,
const lustre_fid *fid,
uint32_t flags)
{
int fd;
int tmp;
int saved_msg_level = llapi_msg_get_level();
struct llapi_layout *layout = NULL;
/* Prevent llapi internal routines from writing to console
* while executing this function, then restore previous message
* level. */
llapi_msg_set_level(LLAPI_MSG_OFF);
fd = llapi_open_by_fid(lustre_dir, fid, O_RDONLY);
llapi_msg_set_level(saved_msg_level);
if (fd < 0)
return NULL;
layout = llapi_layout_get_by_fd(fd, flags);
tmp = errno;
close(fd);
errno = tmp;
return layout;
}
/**
* Get the striping layout for the file at \a path.
*
* If \a flags contains LAYOUT_GET_EXPECTED, substitute
* expected inherited attribute values for unspecified attributes. See
* llapi_layout_expected().
*
* \param[in] path path for which to get the layout
* \param[in] flags flags to control how layout is retrieved
*
* \retval valid llapi_layout pointer on success
* \retval NULL if an error occurs
*/
struct llapi_layout *llapi_layout_get_by_path(const char *path, uint32_t flags)
{
struct llapi_layout *layout = NULL;
int fd;
int tmp;
if (flags & LAYOUT_GET_EXPECTED)
return llapi_layout_expected(path);
fd = open(path, O_RDONLY);
if (fd < 0)
return layout;
layout = llapi_layout_get_by_fd(fd, flags);
tmp = errno;
close(fd);
errno = tmp;
return layout;
}
void test2(void)
{
int fd;
int rc;
char path[PATH_MAX];
snprintf(path, sizeof(path), "%s/%s", lustre_dir, T0FILE);
fd = open(path, O_RDONLY);
ASSERTF(fd >= 0, "open(%s): errno = %d", path, errno);
struct llapi_layout *layout = llapi_layout_get_by_fd(fd, 0);
ASSERTF(layout != NULL, "errno = %d", errno);
rc = close(fd);
ASSERTF(rc == 0, "close(%s): errno = %d", path, errno);
__test1_helper(layout);
llapi_layout_free(layout);
}
/**
* Get the expected striping layout for a file at \a path.
*
* Substitute expected inherited attribute values for unspecified
* attributes. Unspecified attributes may belong to directories and
* never-written-to files, and indicate that default values will be
* assigned when files are created or first written to. A default value
* is inherited from the parent directory if the attribute is specified
* there, otherwise it is inherited from the filesystem root.
* Unspecified attributes normally have the value LLAPI_LAYOUT_DEFAULT.
*
* The complete \a path need not refer to an existing file or directory,
* but some leading portion of it must reside within a lustre filesystem.
* A use case for this interface would be to obtain the literal striping
* values that would be assigned to a new file in a given directory.
*
* \param[in] path path for which to get the expected layout
*
* \retval valid llapi_layout pointer on success
* \retval NULL if an error occurs
*/
static struct llapi_layout *llapi_layout_expected(const char *path)
{
struct llapi_layout *path_layout = NULL;
struct llapi_layout *donor_layout;
char donor_path[PATH_MAX];
struct stat st;
int fd;
int rc;
fd = open(path, O_RDONLY);
if (fd < 0 && errno != ENOENT)
return NULL;
if (fd >= 0) {
int tmp;
path_layout = llapi_layout_get_by_fd(fd, 0);
tmp = errno;
close(fd);
errno = tmp;
}
if (path_layout == NULL) {
if (errno != ENODATA && errno != ENOENT)
return NULL;
path_layout = llapi_layout_alloc();
if (path_layout == NULL)
return NULL;
}
if (is_fully_specified(path_layout))
return path_layout;
rc = stat(path, &st);
if (rc < 0 && errno != ENOENT) {
llapi_layout_free(path_layout);
return NULL;
}
/* If path is a not a directory or doesn't exist, inherit unspecified
* attributes from parent directory. */
if ((rc == 0 && !S_ISDIR(st.st_mode)) ||
(rc < 0 && errno == ENOENT)) {
get_parent_dir(path, donor_path, sizeof(donor_path));
donor_layout = llapi_layout_get_by_path(donor_path, 0);
if (donor_layout != NULL) {
inherit_layout_attributes(donor_layout, path_layout);
llapi_layout_free(donor_layout);
if (is_fully_specified(path_layout))
return path_layout;
}
}
/* Inherit remaining unspecified attributes from the filesystem root. */
rc = llapi_search_mounts(path, 0, donor_path, NULL);
if (rc < 0) {
llapi_layout_free(path_layout);
return NULL;
}
donor_layout = llapi_layout_get_by_path(donor_path, 0);
if (donor_layout == NULL) {
llapi_layout_free(path_layout);
return NULL;
}
inherit_layout_attributes(donor_layout, path_layout);
llapi_layout_free(donor_layout);
return path_layout;
}
void test6(void)
{
errno = 0;
struct llapi_layout *layout = llapi_layout_get_by_fd(9999, 0);
ASSERTF(layout == NULL && errno == EBADF, "errno = %d", errno);
}
