xref: /illumos-gate/usr/src/cmd/zfs/zfs_iter.c (revision 0173c38a73f34277e0c97a19fedfd25d81ba8380)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <libintl.h>
29 #include <libuutil.h>
30 #include <stddef.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <strings.h>
34 
35 #include <libzfs.h>
36 
37 #include "zfs_util.h"
38 #include "zfs_iter.h"
39 
40 /*
41  * This is a private interface used to gather up all the datasets specified on
42  * the command line so that we can iterate over them in order.
43  *
44  * First, we iterate over all filesystems, gathering them together into an
45  * AVL tree.  We report errors for any explicitly specified datasets
46  * that we couldn't open.
47  *
48  * When finished, we have an AVL tree of ZFS handles.  We go through and execute
49  * the provided callback for each one, passing whatever data the user supplied.
50  */
51 
52 typedef struct zfs_node {
53 	zfs_handle_t	*zn_handle;
54 	uu_avl_node_t	zn_avlnode;
55 } zfs_node_t;
56 
57 typedef struct callback_data {
58 	uu_avl_t	*cb_avl;
59 	int		cb_recurse;
60 	zfs_type_t	cb_types;
61 	zfs_sort_column_t *cb_sortcol;
62 } callback_data_t;
63 
64 uu_avl_pool_t *avl_pool;
65 
66 /*
67  * Called for each dataset.  If the object the object is of an appropriate type,
68  * add it to the avl tree and recurse over any children as necessary.
69  */
70 int
71 zfs_callback(zfs_handle_t *zhp, void *data)
72 {
73 	callback_data_t *cb = data;
74 	int dontclose = 0;
75 
76 	/*
77 	 * If this object is of the appropriate type, add it to the AVL tree.
78 	 */
79 	if (zfs_get_type(zhp) & cb->cb_types) {
80 		uu_avl_index_t idx;
81 		zfs_node_t *node = safe_malloc(sizeof (zfs_node_t));
82 
83 		node->zn_handle = zhp;
84 		uu_avl_node_init(node, &node->zn_avlnode, avl_pool);
85 		if (uu_avl_find(cb->cb_avl, node, cb->cb_sortcol,
86 		    &idx) == NULL) {
87 			uu_avl_insert(cb->cb_avl, node, idx);
88 			dontclose = 1;
89 		} else {
90 			free(node);
91 		}
92 	}
93 
94 	/*
95 	 * Recurse if necessary.
96 	 */
97 	if (cb->cb_recurse && (zfs_get_type(zhp) == ZFS_TYPE_FILESYSTEM ||
98 	    (zfs_get_type(zhp) == ZFS_TYPE_VOLUME && (cb->cb_types &
99 	    ZFS_TYPE_SNAPSHOT))))
100 		(void) zfs_iter_children(zhp, zfs_callback, data);
101 
102 	if (!dontclose)
103 		zfs_close(zhp);
104 
105 	return (0);
106 }
107 
108 void
109 zfs_add_sort_column(zfs_sort_column_t **sc, zfs_prop_t prop,
110     boolean_t reverse)
111 {
112 	zfs_sort_column_t *col;
113 
114 	col = safe_malloc(sizeof (zfs_sort_column_t));
115 
116 	col->sc_prop = prop;
117 	col->sc_reverse = reverse;
118 	col->sc_next = NULL;
119 
120 	if (*sc == NULL) {
121 		col->sc_last = col;
122 		*sc = col;
123 	} else {
124 		(*sc)->sc_last->sc_next = col;
125 		(*sc)->sc_last = col;
126 	}
127 }
128 
129 void
130 zfs_free_sort_columns(zfs_sort_column_t *sc)
131 {
132 	zfs_sort_column_t *col;
133 
134 	while (sc != NULL) {
135 		col = sc->sc_next;
136 		free(sc);
137 		sc = col;
138 	}
139 }
140 
141 /* ARGSUSED */
142 static int
143 zfs_compare(const void *larg, const void *rarg, void *unused)
144 {
145 	zfs_handle_t *l = ((zfs_node_t *)larg)->zn_handle;
146 	zfs_handle_t *r = ((zfs_node_t *)rarg)->zn_handle;
147 	const char *lname = zfs_get_name(l);
148 	const char *rname = zfs_get_name(r);
149 	char *lat, *rat;
150 	uint64_t lcreate, rcreate;
151 	int ret;
152 
153 	lat = (char *)strchr(lname, '@');
154 	rat = (char *)strchr(rname, '@');
155 
156 	if (lat != NULL)
157 		*lat = '\0';
158 	if (rat != NULL)
159 		*rat = '\0';
160 
161 	ret = strcmp(lname, rname);
162 	if (ret == 0) {
163 		/*
164 		 * If we're comparing a dataset to one of its snapshots, we
165 		 * always make the full dataset first.
166 		 */
167 		if (lat == NULL) {
168 			ret = -1;
169 		} else if (rat == NULL) {
170 			ret = 1;
171 		} else {
172 			/*
173 			 * If we have two snapshots from the same dataset, then
174 			 * we want to sort them according to creation time.  We
175 			 * use the hidden CREATETXG property to get an absolute
176 			 * ordering of snapshots.
177 			 */
178 			lcreate = zfs_prop_get_int(l, ZFS_PROP_CREATETXG);
179 			rcreate = zfs_prop_get_int(r, ZFS_PROP_CREATETXG);
180 
181 			if (lcreate < rcreate)
182 				ret = -1;
183 			else if (lcreate > rcreate)
184 				ret = 1;
185 		}
186 	}
187 
188 	if (lat != NULL)
189 		*lat = '@';
190 	if (rat != NULL)
191 		*rat = '@';
192 
193 	return (ret);
194 }
195 
196 /*
197  * Sort datasets by specified columns.
198  *
199  * o  Numeric types sort in ascending order.
200  * o  String types sort in alphabetical order.
201  * o  Types inappropriate for a row sort that row to the literal
202  *    bottom, regardless of the specified ordering.
203  *
204  * If no sort columns are specified, or two datasets compare equally
205  * across all specified columns, they are sorted alphabetically by name
206  * with snapshots grouped under their parents.
207  */
208 static int
209 zfs_sort(const void *larg, const void *rarg, void *data)
210 {
211 	zfs_handle_t *l = ((zfs_node_t *)larg)->zn_handle;
212 	zfs_handle_t *r = ((zfs_node_t *)rarg)->zn_handle;
213 	zfs_sort_column_t *sc = (zfs_sort_column_t *)data;
214 	zfs_sort_column_t *psc;
215 
216 	for (psc = sc; psc != NULL; psc = psc->sc_next) {
217 		char lstr[ZFS_MAXPROPLEN], rstr[ZFS_MAXPROPLEN];
218 		uint64_t lnum, rnum;
219 		int lvalid, rvalid;
220 		int ret = 0;
221 
222 		if (zfs_prop_is_string(psc->sc_prop)) {
223 			lvalid = zfs_prop_get(l, psc->sc_prop, lstr,
224 			    sizeof (lstr), NULL, NULL, 0, B_TRUE);
225 			rvalid = zfs_prop_get(r, psc->sc_prop, rstr,
226 			    sizeof (rstr), NULL, NULL, 0, B_TRUE);
227 
228 			if ((lvalid == -1) && (rvalid == -1))
229 				continue;
230 			if (lvalid == -1)
231 				return (1);
232 			else if (rvalid == -1)
233 				return (-1);
234 
235 			ret = strcmp(lstr, rstr);
236 		} else {
237 			lvalid = zfs_prop_valid_for_type(psc->sc_prop,
238 			    zfs_get_type(l));
239 			rvalid = zfs_prop_valid_for_type(psc->sc_prop,
240 			    zfs_get_type(r));
241 
242 			if (!lvalid && !rvalid)
243 				continue;
244 			else if (!lvalid)
245 				return (1);
246 			else if (!rvalid)
247 				return (-1);
248 
249 			(void) zfs_prop_get_numeric(l, psc->sc_prop, &lnum,
250 			    NULL, NULL, 0);
251 			(void) zfs_prop_get_numeric(r, psc->sc_prop, &rnum,
252 			    NULL, NULL, 0);
253 
254 			if (lnum < rnum)
255 				ret = -1;
256 			else if (lnum > rnum)
257 				ret = 1;
258 		}
259 
260 		if (ret != 0) {
261 			if (psc->sc_reverse == B_TRUE)
262 				ret = (ret < 0) ? 1 : -1;
263 			return (ret);
264 		}
265 	}
266 
267 	return (zfs_compare(larg, rarg, NULL));
268 }
269 
270 int
271 zfs_for_each(int argc, char **argv, boolean_t recurse, zfs_type_t types,
272     zfs_sort_column_t *sortcol, zfs_iter_f callback, void *data)
273 {
274 	callback_data_t cb;
275 	int ret = 0;
276 	zfs_node_t *node;
277 	uu_avl_walk_t *walk;
278 
279 	avl_pool = uu_avl_pool_create("zfs_pool", sizeof (zfs_node_t),
280 	    offsetof(zfs_node_t, zn_avlnode), zfs_sort, UU_DEFAULT);
281 
282 	if (avl_pool == NULL) {
283 		(void) fprintf(stderr,
284 		    gettext("internal error: out of memory\n"));
285 		exit(1);
286 	}
287 
288 	cb.cb_sortcol = sortcol;
289 	cb.cb_recurse = recurse;
290 	cb.cb_types = types;
291 	if ((cb.cb_avl = uu_avl_create(avl_pool, NULL, UU_DEFAULT)) == NULL) {
292 		(void) fprintf(stderr,
293 		    gettext("internal error: out of memory\n"));
294 		exit(1);
295 	}
296 
297 	if (argc == 0) {
298 		/*
299 		 * If given no arguments, iterate over all datasets.
300 		 */
301 		cb.cb_recurse = 1;
302 		ret = zfs_iter_root(g_zfs, zfs_callback, &cb);
303 	} else {
304 		int i;
305 		zfs_handle_t *zhp;
306 		zfs_type_t argtype;
307 
308 		/*
309 		 * If we're recursive, then we always allow filesystems as
310 		 * arguments.  If we also are interested in snapshots, then we
311 		 * can take volumes as well.
312 		 */
313 		argtype = types;
314 		if (recurse) {
315 			argtype |= ZFS_TYPE_FILESYSTEM;
316 			if (types & ZFS_TYPE_SNAPSHOT)
317 				argtype |= ZFS_TYPE_VOLUME;
318 		}
319 
320 		for (i = 0; i < argc; i++) {
321 			if ((zhp = zfs_open(g_zfs, argv[i], argtype)) != NULL)
322 				ret |= zfs_callback(zhp, &cb);
323 			else
324 				ret = 1;
325 		}
326 	}
327 
328 	/*
329 	 * At this point we've got our AVL tree full of zfs handles, so iterate
330 	 * over each one and execute the real user callback.
331 	 */
332 	for (node = uu_avl_first(cb.cb_avl); node != NULL;
333 	    node = uu_avl_next(cb.cb_avl, node))
334 		ret |= callback(node->zn_handle, data);
335 
336 	/*
337 	 * Finally, clean up the AVL tree.
338 	 */
339 	if ((walk = uu_avl_walk_start(cb.cb_avl, UU_WALK_ROBUST)) == NULL) {
340 		(void) fprintf(stderr,
341 		    gettext("internal error: out of memory"));
342 		exit(1);
343 	}
344 
345 	while ((node = uu_avl_walk_next(walk)) != NULL) {
346 		uu_avl_remove(cb.cb_avl, node);
347 		zfs_close(node->zn_handle);
348 		free(node);
349 	}
350 
351 	uu_avl_walk_end(walk);
352 	uu_avl_destroy(cb.cb_avl);
353 	uu_avl_pool_destroy(avl_pool);
354 
355 	return (ret);
356 }
357