/src/openvswitch/lib/shash.c

Source (jump to first uncovered line)
/*
 * Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <config.h>
#include "openvswitch/shash.h"
#include "hash.h"
#include "util.h"

static struct shash_node *shash_find__(const struct shash *,
                                       const char *name, size_t name_len,
                                       size_t hash);

static size_t
hash_name(const char *name)
{
    return hash_string(name, 0);
}

void
shash_init(struct shash *sh)
{
    hmap_init(&sh->map);
}

void
shash_destroy(struct shash *sh)
{
    if (sh) {
        shash_clear(sh);
        hmap_destroy(&sh->map);
    }
}

/* Like shash_destroy(), but also free() each node's 'data'. */
void
shash_destroy_free_data(struct shash *sh)
{
    if (sh) {
        shash_clear_free_data(sh);
        hmap_destroy(&sh->map);
    }
}

void
shash_swap(struct shash *a, struct shash *b)
{
    hmap_swap(&a->map, &b->map);
}

void
shash_moved(struct shash *sh)
{
    hmap_moved(&sh->map);
}

void
shash_clear(struct shash *sh)
{
    struct shash_node *node;

    SHASH_FOR_EACH_SAFE (node, sh) {
        hmap_remove(&sh->map, &node->node);
        free(node->name);
        free(node);
    }
}

/* Like shash_clear(), but also free() each node's 'data'. */
void
shash_clear_free_data(struct shash *sh)
{
    struct shash_node *node;

    SHASH_FOR_EACH_SAFE (node, sh) {
        hmap_remove(&sh->map, &node->node);
        free(node->data);
        free(node->name);
        free(node);
    }
}

bool
shash_is_empty(const struct shash *shash)
{
    return hmap_is_empty(&shash->map);
}

size_t
shash_count(const struct shash *shash)
{
    ovs_assert(shash);
    return hmap_count(&shash->map);
}

static struct shash_node *
shash_add_nocopy__(struct shash *sh, char *name, const void *data, size_t hash)
{
    struct shash_node *node = xmalloc(sizeof *node);
    node->name = name;
    node->data = CONST_CAST(void *, data);
    hmap_insert(&sh->map, &node->node, hash);
    return node;
}

/* It is the caller's responsibility to avoid duplicate names, if that is
 * desirable. */
struct shash_node *
shash_add_nocopy(struct shash *sh, char *name, const void *data)
{
    return shash_add_nocopy__(sh, name, data, hash_name(name));
}

/* It is the caller's responsibility to avoid duplicate names, if that is
 * desirable. */
struct shash_node *
shash_add(struct shash *sh, const char *name, const void *data)
{
    return shash_add_nocopy(sh, xstrdup(name), data);
}

bool
shash_add_once(struct shash *sh, const char *name, const void *data)
{
    if (!shash_find(sh, name)) {
        shash_add(sh, name, data);
        return true;
    } else {
        return false;
    }
}

void
shash_add_assert(struct shash *sh, const char *name, const void *data)
{
    ovs_assert(shash_add_once(sh, name, data));
}

/* Searches for 'name' in 'sh'.  If it does not already exist, adds it along
 * with 'data' and returns NULL.  If it does already exist, replaces its data
 * by 'data' and returns the data that it formerly contained. */
void *
shash_replace(struct shash *sh, const char *name, const void *data)
{
    size_t hash = hash_name(name);
    struct shash_node *node;

    node = shash_find__(sh, name, strlen(name), hash);
    if (!node) {
        shash_add_nocopy__(sh, xstrdup(name), data, hash);
        return NULL;
    } else {
        void *old_data = node->data;
        node->data = CONST_CAST(void *, data);
        return old_data;
    }
}

/* Searches for 'name' in 'sh'.  If it does not already exist, adds it along
 * with 'data' and returns NULL.  If it does already exist, replaces its data
 * by 'data' and returns the data that it formerly contained.
 *
 * Takes ownership of 'name'. */
void *
shash_replace_nocopy(struct shash *sh, char *name, const void *data)
{
    size_t hash = hash_name(name);
    struct shash_node *node;

    node = shash_find__(sh, name, strlen(name), hash);
    if (!node) {
        shash_add_nocopy__(sh, name, data, hash);
        return NULL;
    } else {
        free(name);
        void *old_data = node->data;
        node->data = CONST_CAST(void *, data);
        return old_data;
    }
}

/* Deletes 'node' from 'sh' and frees the node's name.  The caller is still
 * responsible for freeing the node's data, if necessary. */
void
shash_delete(struct shash *sh, struct shash_node *node)
{
    free(shash_steal(sh, node));
}

/* Deletes 'node' from 'sh'.  Neither the node's name nor its data is freed;
 * instead, ownership is transferred to the caller.  Returns the node's
 * name. */
char *
shash_steal(struct shash *sh, struct shash_node *node)
{
    if (!node) {
        return NULL;
    }

    char *name = node->name;

    hmap_remove(&sh->map, &node->node);
    free(node);
    return name;
}

static struct shash_node *
shash_find__(const struct shash *sh, const char *name, size_t name_len,
             size_t hash)
{
    struct shash_node *node;

    HMAP_FOR_EACH_WITH_HASH (node, node, hash, &sh->map) {
        if (!strncmp(node->name, name, name_len) && !node->name[name_len]) {
            return node;
        }
    }
    return NULL;
}

/* If there are duplicates, returns a random element. */
struct shash_node *
shash_find(const struct shash *sh, const char *name)
{
    return shash_find__(sh, name, strlen(name), hash_name(name));
}

/* Finds and returns a shash_node within 'sh' that has the given 'name' that is
 * exactly 'len' bytes long.  Returns NULL if no node in 'sh' has that name. */
struct shash_node *
shash_find_len(const struct shash *sh, const char *name, size_t len)
{
    return shash_find__(sh, name, len, hash_bytes(name, len, 0));
}

void *
shash_find_data(const struct shash *sh, const char *name)
{
    struct shash_node *node = shash_find(sh, name);
    return node ? node->data : NULL;
}

void *
shash_find_and_delete(struct shash *sh, const char *name)
{
    struct shash_node *node = shash_find(sh, name);
    if (node) {
        void *data = node->data;
        shash_delete(sh, node);
        return data;
    } else {
        return NULL;
    }
}

void *
shash_find_and_delete_assert(struct shash *sh, const char *name)
{
    void *data = shash_find_and_delete(sh, name);
    ovs_assert(data);
    return data;
}

struct shash_node *
shash_first(const struct shash *shash)
{
    struct hmap_node *node = hmap_first(&shash->map);
    return node ? CONTAINER_OF(node, struct shash_node, node) : NULL;
}

static int
compare_nodes_by_name(const void *a_, const void *b_)
{
    const struct shash_node *const *a = a_;
    const struct shash_node *const *b = b_;
    return strcmp((*a)->name, (*b)->name);
}

const struct shash_node **
shash_sort(const struct shash *sh)
{
    if (shash_is_empty(sh)) {
        return NULL;
    } else {
        const struct shash_node **nodes;
        struct shash_node *node;
        size_t i, n;

        n = shash_count(sh);
        nodes = xmalloc(n * sizeof *nodes);
        i = 0;
        SHASH_FOR_EACH (node, sh) {
            nodes[i++] = node;
        }
        ovs_assert(i == n);

        qsort(nodes, n, sizeof *nodes, compare_nodes_by_name);

        return nodes;
    }
}

/* Returns true if 'a' and 'b' contain the same keys (regardless of their
 * values), false otherwise. */
bool
shash_equal_keys(const struct shash *a, const struct shash *b)
{
    struct shash_node *node;

    if (hmap_count(&a->map) != hmap_count(&b->map)) {
        return false;
    }
    SHASH_FOR_EACH (node, a) {
        if (!shash_find(b, node->name)) {
            return false;
        }
    }
    return true;
}

/* Chooses and returns a randomly selected node from 'sh', which must not be
 * empty.
 *
 * I wouldn't depend on this algorithm to be fair, since I haven't analyzed it.
 * But it does at least ensure that any node in 'sh' can be chosen. */
struct shash_node *
shash_random_node(struct shash *sh)
{
    return CONTAINER_OF(hmap_random_node(&sh->map), struct shash_node, node);
}

Coverage Report

Created: 2025-07-01 06:50

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc.
3		*
4		* Licensed under the Apache License, Version 2.0 (the "License");
5		* you may not use this file except in compliance with the License.
6		* You may obtain a copy of the License at:
7		*
8		* http://www.apache.org/licenses/LICENSE-2.0
9		*
10		* Unless required by applicable law or agreed to in writing, software
11		* distributed under the License is distributed on an "AS IS" BASIS,
12		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13		* See the License for the specific language governing permissions and
14		* limitations under the License.
15		*/
16
17		#include <config.h>
18		#include "openvswitch/shash.h"
19		#include "hash.h"
20		#include "util.h"
21
22		static struct shash_node shash_find__(const struct shash ,
23		const char *name, size_t name_len,
24		size_t hash);
25
26		static size_t
27		hash_name(const char *name)
28	0	{
29	0	return hash_string(name, 0);
30	0	}
31
32		void
33		shash_init(struct shash *sh)
34	0	{
35	0	hmap_init(&sh->map);
36	0	}
37
38		void
39		shash_destroy(struct shash *sh)
40	0	{
41	0	if (sh) {
42	0	shash_clear(sh);
43	0	hmap_destroy(&sh->map);
44	0	}
45	0	}
46
47		/* Like shash_destroy(), but also free() each node's 'data'. */
48		void
49		shash_destroy_free_data(struct shash *sh)
50	0	{
51	0	if (sh) {
52	0	shash_clear_free_data(sh);
53	0	hmap_destroy(&sh->map);
54	0	}
55	0	}
56
57		void
58		shash_swap(struct shash a, struct shash b)
59	0	{
60	0	hmap_swap(&a->map, &b->map);
61	0	}
62
63		void
64		shash_moved(struct shash *sh)
65	0	{
66	0	hmap_moved(&sh->map);
67	0	}
68
69		void
70		shash_clear(struct shash *sh)
71	0	{
72	0	struct shash_node *node;
73
74	0	SHASH_FOR_EACH_SAFE (node, sh) {
75	0	hmap_remove(&sh->map, &node->node);
76	0	free(node->name);
77	0	free(node);
78	0	}
79	0	}
80
81		/* Like shash_clear(), but also free() each node's 'data'. */
82		void
83		shash_clear_free_data(struct shash *sh)
84	0	{
85	0	struct shash_node *node;
86
87	0	SHASH_FOR_EACH_SAFE (node, sh) {
88	0	hmap_remove(&sh->map, &node->node);
89	0	free(node->data);
90	0	free(node->name);
91	0	free(node);
92	0	}
93	0	}
94
95		bool
96		shash_is_empty(const struct shash *shash)
97	0	{
98	0	return hmap_is_empty(&shash->map);
99	0	}
100
101		size_t
102		shash_count(const struct shash *shash)
103	0	{
104	0	ovs_assert(shash);
105	0	return hmap_count(&shash->map);
106	0	}
107
108		static struct shash_node *
109		shash_add_nocopy__(struct shash sh, char name, const void *data, size_t hash)
110	0	{
111	0	struct shash_node node = xmalloc(sizeof node);
112	0	node->name = name;
113	0	node->data = CONST_CAST(void *, data);
114	0	hmap_insert(&sh->map, &node->node, hash);
115	0	return node;
116	0	}
117
118		/* It is the caller's responsibility to avoid duplicate names, if that is
119		* desirable. */
120		struct shash_node *
121		shash_add_nocopy(struct shash sh, char name, const void *data)
122	0	{
123	0	return shash_add_nocopy__(sh, name, data, hash_name(name));
124	0	}
125
126		/* It is the caller's responsibility to avoid duplicate names, if that is
127		* desirable. */
128		struct shash_node *
129		shash_add(struct shash sh, const char name, const void *data)
130	0	{
131	0	return shash_add_nocopy(sh, xstrdup(name), data);
132	0	}
133
134		bool
135		shash_add_once(struct shash sh, const char name, const void *data)
136	0	{
137	0	if (!shash_find(sh, name)) {
138	0	shash_add(sh, name, data);
139	0	return true;
140	0	} else {
141	0	return false;
142	0	}
143	0	}
144
145		void
146		shash_add_assert(struct shash sh, const char name, const void *data)
147	0	{
148	0	ovs_assert(shash_add_once(sh, name, data));
149	0	}
150
151		/* Searches for 'name' in 'sh'. If it does not already exist, adds it along
152		* with 'data' and returns NULL. If it does already exist, replaces its data
153		* by 'data' and returns the data that it formerly contained. */
154		void *
155		shash_replace(struct shash sh, const char name, const void *data)
156	0	{
157	0	size_t hash = hash_name(name);
158	0	struct shash_node *node;
159
160	0	node = shash_find__(sh, name, strlen(name), hash);
161	0	if (!node) {
162	0	shash_add_nocopy__(sh, xstrdup(name), data, hash);
163	0	return NULL;
164	0	} else {
165	0	void *old_data = node->data;
166	0	node->data = CONST_CAST(void *, data);
167	0	return old_data;
168	0	}
169	0	}
170
171		/* Searches for 'name' in 'sh'. If it does not already exist, adds it along
172		* with 'data' and returns NULL. If it does already exist, replaces its data
173		* by 'data' and returns the data that it formerly contained.
174		*
175		* Takes ownership of 'name'. */
176		void *
177		shash_replace_nocopy(struct shash sh, char name, const void *data)
178	0	{
179	0	size_t hash = hash_name(name);
180	0	struct shash_node *node;
181
182	0	node = shash_find__(sh, name, strlen(name), hash);
183	0	if (!node) {
184	0	shash_add_nocopy__(sh, name, data, hash);
185	0	return NULL;
186	0	} else {
187	0	free(name);
188	0	void *old_data = node->data;
189	0	node->data = CONST_CAST(void *, data);
190	0	return old_data;
191	0	}
192	0	}
193
194		/* Deletes 'node' from 'sh' and frees the node's name. The caller is still
195		* responsible for freeing the node's data, if necessary. */
196		void
197		shash_delete(struct shash sh, struct shash_node node)
198	0	{
199	0	free(shash_steal(sh, node));
200	0	}
201
202		/* Deletes 'node' from 'sh'. Neither the node's name nor its data is freed;
203		* instead, ownership is transferred to the caller. Returns the node's
204		* name. */
205		char *
206		shash_steal(struct shash sh, struct shash_node node)
207	0	{
208	0	if (!node) {
209	0	return NULL;
210	0	}
211
212	0	char *name = node->name;
213
214	0	hmap_remove(&sh->map, &node->node);
215	0	free(node);
216	0	return name;
217	0	}
218
219		static struct shash_node *
220		shash_find__(const struct shash sh, const char name, size_t name_len,
221		size_t hash)
222	0	{
223	0	struct shash_node *node;
224
225	0	HMAP_FOR_EACH_WITH_HASH (node, node, hash, &sh->map) {
226	0	if (!strncmp(node->name, name, name_len) && !node->name[name_len]) {
227	0	return node;
228	0	}
229	0	}
230	0	return NULL;
231	0	}
232
233		/* If there are duplicates, returns a random element. */
234		struct shash_node *
235		shash_find(const struct shash sh, const char name)
236	0	{
237	0	return shash_find__(sh, name, strlen(name), hash_name(name));
238	0	}
239
240		/* Finds and returns a shash_node within 'sh' that has the given 'name' that is
241		* exactly 'len' bytes long. Returns NULL if no node in 'sh' has that name. */
242		struct shash_node *
243		shash_find_len(const struct shash sh, const char name, size_t len)
244	0	{
245	0	return shash_find__(sh, name, len, hash_bytes(name, len, 0));
246	0	}
247
248		void *
249		shash_find_data(const struct shash sh, const char name)
250	0	{
251	0	struct shash_node *node = shash_find(sh, name);
252	0	return node ? node->data : NULL;
253	0	}
254
255		void *
256		shash_find_and_delete(struct shash sh, const char name)
257	0	{
258	0	struct shash_node *node = shash_find(sh, name);
259	0	if (node) {
260	0	void *data = node->data;
261	0	shash_delete(sh, node);
262	0	return data;
263	0	} else {
264	0	return NULL;
265	0	}
266	0	}
267
268		void *
269		shash_find_and_delete_assert(struct shash sh, const char name)
270	0	{
271	0	void *data = shash_find_and_delete(sh, name);
272	0	ovs_assert(data);
273	0	return data;
274	0	}
275
276		struct shash_node *
277		shash_first(const struct shash *shash)
278	0	{
279	0	struct hmap_node *node = hmap_first(&shash->map);
280	0	return node ? CONTAINER_OF(node, struct shash_node, node) : NULL;
281	0	}
282
283		static int
284		compare_nodes_by_name(const void a_, const void b_)
285	0	{
286	0	const struct shash_node const a = a_;
287	0	const struct shash_node const b = b_;
288	0	return strcmp((a)->name, (b)->name);
289	0	}
290
291		const struct shash_node **
292		shash_sort(const struct shash *sh)
293	0	{
294	0	if (shash_is_empty(sh)) {
295	0	return NULL;
296	0	} else {
297	0	const struct shash_node **nodes;
298	0	struct shash_node *node;
299	0	size_t i, n;
300
301	0	n = shash_count(sh);
302	0	nodes = xmalloc(n * sizeof *nodes);
303	0	i = 0;
304	0	SHASH_FOR_EACH (node, sh) {
305	0	nodes[i++] = node;
306	0	}
307	0	ovs_assert(i == n);
308
309	0	qsort(nodes, n, sizeof *nodes, compare_nodes_by_name);
310
311	0	return nodes;
312	0	}
313	0	}
314
315		/* Returns true if 'a' and 'b' contain the same keys (regardless of their
316		* values), false otherwise. */
317		bool
318		shash_equal_keys(const struct shash a, const struct shash b)
319	0	{
320	0	struct shash_node *node;
321
322	0	if (hmap_count(&a->map) != hmap_count(&b->map)) {
323	0	return false;
324	0	}
325	0	SHASH_FOR_EACH (node, a) {
326	0	if (!shash_find(b, node->name)) {
327	0	return false;
328	0	}
329	0	}
330	0	return true;
331	0	}
332
333		/* Chooses and returns a randomly selected node from 'sh', which must not be
334		* empty.
335		*
336		* I wouldn't depend on this algorithm to be fair, since I haven't analyzed it.
337		* But it does at least ensure that any node in 'sh' can be chosen. */
338		struct shash_node *
339		shash_random_node(struct shash *sh)
340	0	{
341	0	return CONTAINER_OF(hmap_random_node(&sh->map), struct shash_node, node);
342	0	}