Strip partition from device name for whole disks

Under Solaris, the slice number is chopped off when displaying the device name
if the vdev is a whole disk.  Under Linux we should similarly discard the
partition number.  This commit adds the logic to perform the name truncation
for devices ending in -partX, XpX, or X, where X is a string of digits.  The
second case handles devices like md0p0. The third case is limited to scsi and
ide disks, i.e. those beginning with "sd" or "hd", in order to avoid stripping
the number from names like "loop0".

This commit removes the Solaris-specific code for removing slices, since we no
longer reasonably expect our changes to be merged in upstream.  The partition
stripping code was moved off to a helper function to improve readability.

Signed-off-by: Brian Behlendorf <[email protected]>

lib/libzfs/libzfs_pool.c

@@ -3047,6 +3047,35 @@ set_path(zpool_handle_t *zhp, nvlist_t *nv, const char *path)
 	(void) ioctl(zhp->zpool_hdl->libzfs_fd, ZFS_IOC_VDEV_SETPATH, &zc);
 }
 
+/*
+ * Remove partition suffix from a vdev path.  Partition suffixes may take three
+ * forms: "-partX", "pX", or "X", where X is a string of digits.  The second
+ * case only occurs when the suffix is preceded by a digit, i.e. "md0p0" The
+ * third case only occurs when preceded by a string matching the regular
+ * expression "^[hs]d[a-z]+", i.e. a scsi or ide disk.
+ */
+static char *
+strip_partition(libzfs_handle_t *hdl, char *path)
+{
+	char *tmp = zfs_strdup(hdl, path);
+	char *part = NULL, *d = NULL;
+
+	if ((part = strstr(tmp, "-part")) && part != tmp) {
+		d = part + 5;
+	} else if ((part = strrchr(tmp, 'p')) &&
+	    part > tmp + 1 && isdigit(*(part-1))) {
+		d = part + 1;
+	} else if ((tmp[0] == 'h' || tmp[0] == 's') && tmp[1] == 'd') {
+		for (d = &tmp[2]; isalpha(*d); part = ++d);
+	}
+	if (part && d && *d != '\0') {
+		for (; isdigit(*d); d++);
+		if (*d == '\0')
+			*part = '\0';
+	}
+	return (tmp);
+}
+
 #define	PATH_BUF_LEN	64
 
 /*
@@ -3129,32 +3158,13 @@ zpool_vdev_name(libzfs_handle_t *hdl, zpool_handle_t *zhp, nvlist_t *nv,
 			path++;
 		}
 
-#if defined(__sun__) || defined(__sun)
 		/*
-		 * The following code strips the slice from the device path.
+		 * Remove the partition from the path it this is a whole disk.
 		 */
 		if (nvlist_lookup_uint64(nv, ZPOOL_CONFIG_WHOLE_DISK,
 		    &value) == 0 && value) {
-			int pathlen = strlen(path);
-			char *tmp = zfs_strdup(hdl, path);
-
-			/*
-			 * If it starts with c#, and ends with "s0", chop
-			 * the "s0" off, or if it ends with "s0/old", remove
-			 * the "s0" from the middle.
-			 */
-			if (CTD_CHECK(tmp)) {
-				if (strcmp(&tmp[pathlen - 2], "s0") == 0) {
-					tmp[pathlen - 2] = '\0';
-				} else if (pathlen > 6 &&
-				    strcmp(&tmp[pathlen - 6], "s0/old") == 0) {
-					(void) strcpy(&tmp[pathlen - 6],
-					    "/old");
-				}
-			}
-			return (tmp);
+			return strip_partition(hdl, path);
 		}
-#endif
 	} else {
 		verify(nvlist_lookup_string(nv, ZPOOL_CONFIG_TYPE, &path) == 0);