summaryrefslogtreecommitdiffstats
path: root/lib/libzfs
diff options
context:
space:
mode:
authorNed Bass <[email protected]>2010-10-13 16:16:25 -0700
committerBrian Behlendorf <[email protected]>2010-10-22 12:25:30 -0700
commit79e7242a91c17f50c857b53d2a7313cf363ea535 (patch)
tree946f37ab6d0135ca69e5dff07bc249b73b1b2a96 /lib/libzfs
parent0ee8118bd31d1c160123d0aac9c55455706d5975 (diff)
Add helper functions for manipulating device names
This change adds two helper functions for working with vdev names and paths. zfs_resolve_shortname() resolves a shorthand vdev name to an absolute path of a file in /dev, /dev/disk/by-id, /dev/disk/by-label, /dev/disk/by-path, /dev/disk/by-uuid, /dev/disk/zpool. This was previously done only in the function is_shorthand_path(), but we need a general helper function to implement shorthand names for additional zpool subcommands like remove. is_shorthand_path() is accordingly updated to call the helper function. There is a minor change in the way zfs_resolve_shortname() tests if a file exists. is_shorthand_path() effectively used open() and stat64() to test for file existence, since its scope includes testing if a device is a whole disk and collecting file status information. zfs_resolve_shortname(), on the other hand, only uses access() to test for existence and leaves it to the caller to perform any additional file operations. This seemed like the most general and lightweight approach, and still preserves the semantics of is_shorthand_path(). zfs_append_partition() appends a partition suffix to a device path. This should be used to generate the name of a whole disk as it is stored in the vdev label. The user-visible names of whole disks do not contain the partition information, while the name in the vdev label does. The code was lifted from the function make_disks(), which now just calls the helper function. Again, having a helper function to do this supports general handling of shorthand names in the user interface. Signed-off-by: Brian Behlendorf <[email protected]>
Diffstat (limited to 'lib/libzfs')
-rw-r--r--lib/libzfs/libzfs_util.c40
1 files changed, 40 insertions, 0 deletions
diff --git a/lib/libzfs/libzfs_util.c b/lib/libzfs/libzfs_util.c
index d72b7c0fc..01995f802 100644
--- a/lib/libzfs/libzfs_util.c
+++ b/lib/libzfs/libzfs_util.c
@@ -802,6 +802,46 @@ zfs_path_to_zhandle(libzfs_handle_t *hdl, char *path, zfs_type_t argtype)
}
/*
+ * Given a shorthand device name, check if a file by that name exists in a list
+ * of directories under /dev. If one is found, store its full path in the
+ * buffer pointed to by the path argument and return 0, else return -1. The
+ * path buffer must be allocated by the caller.
+ */
+int
+zfs_resolve_shortname(const char *name, char *path, size_t pathlen)
+{
+ int i, err;
+ char dirs[5][9] = {"by-id", "by-label", "by-path", "by-uuid", "zpool"};
+
+ (void) snprintf(path, pathlen, "%s/%s", DISK_ROOT, name);
+ err = access(path, F_OK);
+ for (i = 0; i < 5 && err < 0; i++) {
+ (void) snprintf(path, pathlen, "%s/%s/%s",
+ UDISK_ROOT, dirs[i], name);
+ err = access(path, F_OK);
+ }
+ return err;
+}
+
+/*
+ * Append partition suffix to a device path. This should be used to generate
+ * the name of a whole disk as it is stored in the vdev label. The
+ * user-visible names of whole disks do not contain the partition information.
+ * Modifies buf which must be allocated by the caller.
+ */
+void
+zfs_append_partition(const char *path, char *buf, size_t buflen)
+{
+ if (strncmp(path, UDISK_ROOT, strlen(UDISK_ROOT)) == 0)
+ (void) snprintf(buf, buflen, "%s%s%s", path, "-part",
+ FIRST_SLICE);
+ else
+ (void) snprintf(buf, buflen, "%s%s%s", path,
+ isdigit(path[strlen(path)-1]) ? "p" : "",
+ FIRST_SLICE);
+}
+
+/*
* Initialize the zc_nvlist_dst member to prepare for receiving an nvlist from
* an ioctl().
*/