lbbs/src/trie_dict.c

/***************************************************************************
                                                 trie_dict.c  -  description
                                                         -------------------
        Copyright            : (C) 2004-2025 by Leaflet
        Email                : leaflet@leafok.com
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 3 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/

#include "trie_dict.h"
#include "log.h"
#include <errno.h>
#include <stdlib.h>
#include <strings.h>
#include <stdio.h>
#include <time.h>
#include <unistd.h>
#include <sys/shm.h>
#include <sys/ipc.h>

struct trie_node_pool_t
{
        int shmid;
        int node_count_limit;
        int node_count;
        TRIE_NODE *p_node_free_list;
};
typedef struct trie_node_pool_t TRIE_NODE_POOL;

static TRIE_NODE_POOL *p_trie_node_pool;

int trie_dict_init(const char *filename, int node_count_limit)
{
        int shmid;
        int proj_id;
        key_t key;
        size_t size;
        void *p_shm;
        TRIE_NODE *p_trie_nodes;
        int i;

        if (p_trie_node_pool != NULL)
        {
                log_error("trie_dict_pool already initialized\n");
                return -1;
        }

        if (node_count_limit <= 0 || node_count_limit > TRIE_NODE_PER_POOL)
        {
                log_error("trie_dict_init(%d) error: invalid node_count_limit\n", node_count_limit);
                return -1;
        }

        // Allocate shared memory
        proj_id = (int)(time(NULL) % getpid());
        key = ftok(filename, proj_id);
        if (key == -1)
        {
                log_error("ftok(%s, %d) error (%d)\n", filename, proj_id, errno);
                return -2;
        }

        size = sizeof(TRIE_NODE_POOL) + sizeof(TRIE_NODE) * (size_t)node_count_limit;
        shmid = shmget(key, size, IPC_CREAT | IPC_EXCL | 0600);
        if (shmid == -1)
        {
                log_error("shmget(size = %d) error (%d)\n", size, errno);
                return -3;
        }
        p_shm = shmat(shmid, NULL, 0);
        if (p_shm == (void *)-1)
        {
                log_error("shmat(shmid = %d) error (%d)\n", shmid, errno);
                return -3;
        }

        p_trie_node_pool = p_shm;
        p_trie_node_pool->shmid = shmid;
        p_trie_node_pool->node_count_limit = node_count_limit;
        p_trie_node_pool->node_count = 0;

        p_trie_nodes = p_shm + sizeof(TRIE_NODE_POOL);
        p_trie_node_pool->p_node_free_list = &(p_trie_nodes[0]);
        for (i = 0; i < node_count_limit - 1; i++)
        {
                p_trie_nodes[i].p_nodes[0] = &(p_trie_nodes[i + 1]);
        }
        p_trie_nodes[node_count_limit - 1].p_nodes[0] = NULL;

        return 0;
}

void trie_dict_cleanup(void)
{
        int shmid;

        if (p_trie_node_pool == NULL)
        {
                return;
        }

        shmid = p_trie_node_pool->shmid;

        detach_trie_dict_shm();

        if (shmctl(shmid, IPC_RMID, NULL) == -1)
        {
                log_error("shmctl(shmid = %d, IPC_RMID) error (%d)\n", shmid, errno);
        }
}

int set_trie_dict_shm_readonly(void)
{
        int shmid;
        void *p_shm;

        if (p_trie_node_pool == NULL)
        {
                log_error("trie_dict_pool not initialized\n");
                return -1;
        }

        shmid = p_trie_node_pool->shmid;

        // Remap shared memory in read-only mode
        p_shm = shmat(shmid, p_trie_node_pool, SHM_RDONLY | SHM_REMAP);
        if (p_shm == (void *)-1)
        {
                log_error("shmat(trie_node_pool shmid=%d) error (%d)\n", shmid, errno);
                return -1;
        }

        p_trie_node_pool = p_shm;

        return 0;
}

int detach_trie_dict_shm(void)
{
        if (p_trie_node_pool != NULL && shmdt(p_trie_node_pool) == -1)
        {
                log_error("shmdt(trie_node_pool) error (%d)\n", errno);
                return -1;
        }

        p_trie_node_pool = NULL;

        return 0;
}

TRIE_NODE *trie_dict_create(void)
{
        TRIE_NODE *p_dict = NULL;

        if (p_trie_node_pool != NULL && p_trie_node_pool->p_node_free_list != NULL)
        {
                p_dict = p_trie_node_pool->p_node_free_list;
                p_trie_node_pool->p_node_free_list = p_dict->p_nodes[0];

                bzero(p_dict, sizeof(*p_dict));

                p_trie_node_pool->node_count++;
        }
        else if (p_trie_node_pool != NULL)
        {
                log_error("trie_dict_create() error: node depleted %d >= %d\n", p_trie_node_pool->node_count, p_trie_node_pool->node_count_limit);
        }

        return p_dict;
}

void trie_dict_destroy(TRIE_NODE *p_dict)
{
        if (p_trie_node_pool == NULL || p_dict == NULL)
        {
                return;
        }

        for (int i = 0; i < TRIE_CHILDREN; i++)
        {
                if (p_dict->p_nodes[i] != NULL)
                {
                        trie_dict_destroy(p_dict->p_nodes[i]);
                }
        }

        bzero(p_dict, sizeof(*p_dict));

        p_dict->p_nodes[0] = p_trie_node_pool->p_node_free_list;
        p_trie_node_pool->p_node_free_list = p_dict;

        p_trie_node_pool->node_count--;
}

int trie_dict_set(TRIE_NODE *p_dict, const char *key, int64_t value)
{
        int offset;

        if (p_dict == NULL)
        {
                return -1;
        }

        while (key != NULL && *key != '\0')
        {
                offset = (256 + *key) % 256;
                if (offset < 0 || offset >= TRIE_CHILDREN) // incorrect key character
                {
                        return -1;
                }

                if (*(key + 1) == '\0')
                {
                        if (p_dict->flags[offset] == 0 || p_dict->values[offset] != value)
                        {
                                p_dict->values[offset] = value;
                                p_dict->flags[offset] = 1;
                                return 1; // Set to new value
                        }
                        return 0; // Unchanged
                }
                else
                {
                        if (p_dict->p_nodes[offset] == NULL)
                        {
                                if ((p_dict->p_nodes[offset] = trie_dict_create()) == NULL)
                                {
                                        return -2; // OOM
                                }
                        }
                        p_dict = p_dict->p_nodes[offset];
                        key++;
                }
        }

        return -1; // NULL key
}

int trie_dict_get(TRIE_NODE *p_dict, const char *key, int64_t *p_value)
{
        int offset;

        if (p_dict == NULL)
        {
                return -1;
        }

        while (key != NULL && *key != '\0')
        {
                offset = (256 + *key) % 256;
                if (offset < 0 || offset >= TRIE_CHILDREN) // incorrect key character
                {
                        return -1;
                }

                if (*(key + 1) == '\0')
                {
                        if (p_dict->flags[offset] != 0)
                        {
                                *p_value = p_dict->values[offset];
                                return 1; // Found
                        }
                        else
                        {
                                return 0; // Not exist
                        }
                }
                else if (p_dict->p_nodes[offset] == NULL)
                {
                        return 0; // Not exist
                }
                else
                {
                        p_dict = p_dict->p_nodes[offset];
                        key++;
                }
        }

        return -1; // NULL key
}

int trie_dict_del(TRIE_NODE *p_dict, const char *key)
{
        int offset;

        if (p_dict == NULL)
        {
                return -1;
        }

        while (key != NULL && *key != '\0')
        {
                offset = (256 + *key) % 256;
                if (offset < 0 || offset >= TRIE_CHILDREN) // incorrect key character
                {
                        return -1;
                }

                if (*(key + 1) == '\0')
                {
                        if (p_dict->flags[offset] != 0)
                        {
                                p_dict->flags[offset] = 0;
                                p_dict->values[offset] = 0;
                                return 1; // Done
                        }
                        else
                        {
                                return 0; // Not exist
                        }
                }
                else if (p_dict->p_nodes[offset] == NULL)
                {
                        return 0; // Not exist
                }
                else
                {
                        p_dict = p_dict->p_nodes[offset];
                        key++;
                }
        }

        return -1; // NULL key
}

static void _trie_dict_traverse(TRIE_NODE *p_dict, trie_dict_traverse_cb cb, char *key, int depth)
{
        if (p_dict == NULL || depth >= TRIE_MAX_KEY_LEN)
        {
                return;
        }

        for (int i = 0; i < TRIE_CHILDREN; i++)
        {
                if (p_dict->flags[i] != 0)
                {
                        key[depth] = (char)i;
                        key[depth + 1] = '\0';
                        (*cb)(key, p_dict->values[i]);
                }

                if (p_dict->p_nodes[i] != NULL && depth + 1 < TRIE_MAX_KEY_LEN)
                {
                        key[depth] = (char)i;
                        _trie_dict_traverse(p_dict->p_nodes[i], cb, key, depth + 1);
                }
        }
}

void trie_dict_traverse(TRIE_NODE *p_dict, trie_dict_traverse_cb cb)
{
        char key[TRIE_MAX_KEY_LEN + 1];

        if (p_dict == NULL)
        {
                return;
        }

        _trie_dict_traverse(p_dict, cb, key, 0);
}

int trie_dict_used_nodes(void)
{
        return (p_trie_node_pool == NULL ? -1 : p_trie_node_pool->node_count);
}
1	/***************************************************************************
2	trie_dict.c - description
3	-------------------
4	Copyright : (C) 2004-2025 by Leaflet
5	Email : leaflet@leafok.com
6	***************************************************************************/
7
8	/***************************************************************************
9	* *
10	* This program is free software; you can redistribute it and/or modify *
11	* it under the terms of the GNU General Public License as published by *
12	* the Free Software Foundation; either version 3 of the License, or *
13	* (at your option) any later version. *
14	* *
15	***************************************************************************/
16
17	#include "trie_dict.h"
18	#include "log.h"
19	#include <errno.h>
20	#include <stdlib.h>
21	#include <strings.h>
22	#include <stdio.h>
23	#include <time.h>
24	#include <unistd.h>
25	#include <sys/shm.h>
26	#include <sys/ipc.h>
27
28	struct trie_node_pool_t
29	{
30	int shmid;
31	int node_count_limit;
32	int node_count;
33	TRIE_NODE *p_node_free_list;
34	};
35	typedef struct trie_node_pool_t TRIE_NODE_POOL;
36
37	static TRIE_NODE_POOL *p_trie_node_pool;
38
39	int trie_dict_init(const char *filename, int node_count_limit)
40	{
41	int shmid;
42	int proj_id;
43	key_t key;
44	size_t size;
45	void *p_shm;
46	TRIE_NODE *p_trie_nodes;
47	int i;
48
49	if (p_trie_node_pool != NULL)
50	{
51	log_error("trie_dict_pool already initialized\n");
52	return -1;
53	}
54
55	if (node_count_limit <= 0 \|\| node_count_limit > TRIE_NODE_PER_POOL)
56	{
57	log_error("trie_dict_init(%d) error: invalid node_count_limit\n", node_count_limit);
58	return -1;
59	}
60
61	// Allocate shared memory
62	proj_id = (int)(time(NULL) % getpid());
63	key = ftok(filename, proj_id);
64	if (key == -1)
65	{
66	log_error("ftok(%s, %d) error (%d)\n", filename, proj_id, errno);
67	return -2;
68	}
69
70	size = sizeof(TRIE_NODE_POOL) + sizeof(TRIE_NODE) * (size_t)node_count_limit;
71	shmid = shmget(key, size, IPC_CREAT \| IPC_EXCL \| 0600);
72	if (shmid == -1)
73	{
74	log_error("shmget(size = %d) error (%d)\n", size, errno);
75	return -3;
76	}
77	p_shm = shmat(shmid, NULL, 0);
78	if (p_shm == (void *)-1)
79	{
80	log_error("shmat(shmid = %d) error (%d)\n", shmid, errno);
81	return -3;
82	}
83
84	p_trie_node_pool = p_shm;
85	p_trie_node_pool->shmid = shmid;
86	p_trie_node_pool->node_count_limit = node_count_limit;
87	p_trie_node_pool->node_count = 0;
88
89	p_trie_nodes = p_shm + sizeof(TRIE_NODE_POOL);
90	p_trie_node_pool->p_node_free_list = &(p_trie_nodes[0]);
91	for (i = 0; i < node_count_limit - 1; i++)
92	{
93	p_trie_nodes[i].p_nodes[0] = &(p_trie_nodes[i + 1]);
94	}
95	p_trie_nodes[node_count_limit - 1].p_nodes[0] = NULL;
96
97	return 0;
98	}
99
100	void trie_dict_cleanup(void)
101	{
102	int shmid;
103
104	if (p_trie_node_pool == NULL)
105	{
106	return;
107	}
108
109	shmid = p_trie_node_pool->shmid;
110
111	detach_trie_dict_shm();
112
113	if (shmctl(shmid, IPC_RMID, NULL) == -1)
114	{
115	log_error("shmctl(shmid = %d, IPC_RMID) error (%d)\n", shmid, errno);
116	}
117	}
118
119	int set_trie_dict_shm_readonly(void)
120	{
121	int shmid;
122	void *p_shm;
123
124	if (p_trie_node_pool == NULL)
125	{
126	log_error("trie_dict_pool not initialized\n");
127	return -1;
128	}
129
130	shmid = p_trie_node_pool->shmid;
131
132	// Remap shared memory in read-only mode
133	p_shm = shmat(shmid, p_trie_node_pool, SHM_RDONLY \| SHM_REMAP);
134	if (p_shm == (void *)-1)
135	{
136	log_error("shmat(trie_node_pool shmid=%d) error (%d)\n", shmid, errno);
137	return -1;
138	}
139
140	p_trie_node_pool = p_shm;
141
142	return 0;
143	}
144
145	int detach_trie_dict_shm(void)
146	{
147	if (p_trie_node_pool != NULL && shmdt(p_trie_node_pool) == -1)
148	{
149	log_error("shmdt(trie_node_pool) error (%d)\n", errno);
150	return -1;
151	}
152
153	p_trie_node_pool = NULL;
154
155	return 0;
156	}
157
158	TRIE_NODE *trie_dict_create(void)
159	{
160	TRIE_NODE *p_dict = NULL;
161
162	if (p_trie_node_pool != NULL && p_trie_node_pool->p_node_free_list != NULL)
163	{
164	p_dict = p_trie_node_pool->p_node_free_list;
165	p_trie_node_pool->p_node_free_list = p_dict->p_nodes[0];
166
167	bzero(p_dict, sizeof(*p_dict));
168
169	p_trie_node_pool->node_count++;
170	}
171	else if (p_trie_node_pool != NULL)
172	{
173	log_error("trie_dict_create() error: node depleted %d >= %d\n", p_trie_node_pool->node_count, p_trie_node_pool->node_count_limit);
174	}
175
176	return p_dict;
177	}
178
179	void trie_dict_destroy(TRIE_NODE *p_dict)
180	{
181	if (p_trie_node_pool == NULL \|\| p_dict == NULL)
182	{
183	return;
184	}
185
186	for (int i = 0; i < TRIE_CHILDREN; i++)
187	{
188	if (p_dict->p_nodes[i] != NULL)
189	{
190	trie_dict_destroy(p_dict->p_nodes[i]);
191	}
192	}
193
194	bzero(p_dict, sizeof(*p_dict));
195
196	p_dict->p_nodes[0] = p_trie_node_pool->p_node_free_list;
197	p_trie_node_pool->p_node_free_list = p_dict;
198
199	p_trie_node_pool->node_count--;
200	}
201
202	int trie_dict_set(TRIE_NODE p_dict, const char key, int64_t value)
203	{
204	int offset;
205
206	if (p_dict == NULL)
207	{
208	return -1;
209	}
210
211	while (key != NULL && *key != '\0')
212	{
213	offset = (256 + *key) % 256;
214	if (offset < 0 \|\| offset >= TRIE_CHILDREN) // incorrect key character
215	{
216	return -1;
217	}
218
219	if (*(key + 1) == '\0')
220	{
221	if (p_dict->flags[offset] == 0 \|\| p_dict->values[offset] != value)
222	{
223	p_dict->values[offset] = value;
224	p_dict->flags[offset] = 1;
225	return 1; // Set to new value
226	}
227	return 0; // Unchanged
228	}
229	else
230	{
231	if (p_dict->p_nodes[offset] == NULL)
232	{
233	if ((p_dict->p_nodes[offset] = trie_dict_create()) == NULL)
234	{
235	return -2; // OOM
236	}
237	}
238	p_dict = p_dict->p_nodes[offset];
239	key++;
240	}
241	}
242
243	return -1; // NULL key
244	}
245
246	int trie_dict_get(TRIE_NODE p_dict, const char key, int64_t *p_value)
247	{
248	int offset;
249
250	if (p_dict == NULL)
251	{
252	return -1;
253	}
254
255	while (key != NULL && *key != '\0')
256	{
257	offset = (256 + *key) % 256;
258	if (offset < 0 \|\| offset >= TRIE_CHILDREN) // incorrect key character
259	{
260	return -1;
261	}
262
263	if (*(key + 1) == '\0')
264	{
265	if (p_dict->flags[offset] != 0)
266	{
267	*p_value = p_dict->values[offset];
268	return 1; // Found
269	}
270	else
271	{
272	return 0; // Not exist
273	}
274	}
275	else if (p_dict->p_nodes[offset] == NULL)
276	{
277	return 0; // Not exist
278	}
279	else
280	{
281	p_dict = p_dict->p_nodes[offset];
282	key++;
283	}
284	}
285
286	return -1; // NULL key
287	}
288
289	int trie_dict_del(TRIE_NODE p_dict, const char key)
290	{
291	int offset;
292
293	if (p_dict == NULL)
294	{
295	return -1;
296	}
297
298	while (key != NULL && *key != '\0')
299	{
300	offset = (256 + *key) % 256;
301	if (offset < 0 \|\| offset >= TRIE_CHILDREN) // incorrect key character
302	{
303	return -1;
304	}
305
306	if (*(key + 1) == '\0')
307	{
308	if (p_dict->flags[offset] != 0)
309	{
310	p_dict->flags[offset] = 0;
311	p_dict->values[offset] = 0;
312	return 1; // Done
313	}
314	else
315	{
316	return 0; // Not exist
317	}
318	}
319	else if (p_dict->p_nodes[offset] == NULL)
320	{
321	return 0; // Not exist
322	}
323	else
324	{
325	p_dict = p_dict->p_nodes[offset];
326	key++;
327	}
328	}
329
330	return -1; // NULL key
331	}
332
333	static void _trie_dict_traverse(TRIE_NODE p_dict, trie_dict_traverse_cb cb, char key, int depth)
334	{
335	if (p_dict == NULL \|\| depth >= TRIE_MAX_KEY_LEN)
336	{
337	return;
338	}
339
340	for (int i = 0; i < TRIE_CHILDREN; i++)
341	{
342	if (p_dict->flags[i] != 0)
343	{
344	key[depth] = (char)i;
345	key[depth + 1] = '\0';
346	(*cb)(key, p_dict->values[i]);
347	}
348
349	if (p_dict->p_nodes[i] != NULL && depth + 1 < TRIE_MAX_KEY_LEN)
350	{
351	key[depth] = (char)i;
352	_trie_dict_traverse(p_dict->p_nodes[i], cb, key, depth + 1);
353	}
354	}
355	}
356
357	void trie_dict_traverse(TRIE_NODE *p_dict, trie_dict_traverse_cb cb)
358	{
359	char key[TRIE_MAX_KEY_LEN + 1];
360
361	if (p_dict == NULL)
362	{
363	return;
364	}
365
366	_trie_dict_traverse(p_dict, cb, key, 0);
367	}
368
369	int trie_dict_used_nodes(void)
370	{
371	return (p_trie_node_pool == NULL ? -1 : p_trie_node_pool->node_count);
372	}
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