lbbs/src/trie_dict.c

/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
 * trie_dict
 *   - trie-tree based dict feature
 *
 * Copyright (C) 2004-2026  Leaflet <leaflet@leafok.com>
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "common.h"
#include "log.h"
#include "trie_dict.h"
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/stat.h>

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

static char trie_node_shm_name[FILE_NAME_LEN];
static TRIE_NODE_POOL *p_trie_node_pool;

int trie_dict_init(const char *filename, int node_count_limit)
{
        char filepath[FILE_PATH_LEN];
        int fd;
        size_t size;
        void *p_shm;
        TRIE_NODE *p_trie_nodes;
        int i;

        if (filename == NULL)
        {
                log_error("NULL pointer error");
                return -1;
        }

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

        // Allocate shared memory
        size = sizeof(TRIE_NODE_POOL) + sizeof(TRIE_NODE) * (size_t)node_count_limit;

        strncpy(filepath, filename, sizeof(filepath) - 1);
        filepath[sizeof(filepath) - 1] = '\0';
        snprintf(trie_node_shm_name, sizeof(trie_node_shm_name), "/TRIE_DICT_SHM_%s", basename(filepath));

        if (shm_unlink(trie_node_shm_name) == -1 && errno != ENOENT)
        {
                log_error("shm_unlink(%s) error (%d)", trie_node_shm_name, errno);
                return -2;
        }

        if ((fd = shm_open(trie_node_shm_name, O_CREAT | O_EXCL | O_RDWR, 0600)) == -1)
        {
                log_error("shm_open(%s) error (%d)", trie_node_shm_name, errno);
                return -2;
        }
        if (ftruncate(fd, (off_t)size) == -1)
        {
                log_error("ftruncate(size=%d) error (%d)", size, errno);
                close(fd);
                return -2;
        }

        p_shm = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0L);
        if (p_shm == MAP_FAILED)
        {
                log_error("mmap() error (%d)", errno);
                close(fd);
                return -2;
        }

        if (close(fd) < 0)
        {
                log_error("close(fd) error (%d)", errno);
                return -1;
        }

        p_trie_node_pool = p_shm;
        p_trie_node_pool->shm_size = size;
        p_trie_node_pool->node_count_limit = node_count_limit;
        p_trie_node_pool->node_count = 0;

        p_trie_nodes = (TRIE_NODE *)((char *)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)
{
        if (p_trie_node_pool == NULL)
        {
                return;
        }

        detach_trie_dict_shm();

        if (shm_unlink(trie_node_shm_name) == -1 && errno != ENOENT)
        {
                log_error("shm_unlink(%s) error (%d)", trie_node_shm_name, errno);
        }

        trie_node_shm_name[0] = '\0';
}

int set_trie_dict_shm_readonly(void)
{
        if (p_trie_node_pool != NULL && mprotect(p_trie_node_pool, p_trie_node_pool->shm_size, PROT_READ) < 0)
        {
                log_error("mprotect() error (%d)", errno);
                return -1;
        }

        return 0;
}

int detach_trie_dict_shm(void)
{
        if (p_trie_node_pool != NULL && munmap(p_trie_node_pool, p_trie_node_pool->shm_size) < 0)
        {
                log_error("munmap() error (%d)", 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];

                memset(p_dict, 0, 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", 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]);
                }
        }

        memset(p_dict, 0, 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 = (unsigned char)(*key);
                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 = (unsigned char)(*key);
                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 = (unsigned char)(*key);
                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	sysadm	1.13	/* SPDX-License-Identifier: GPL-3.0-or-later */
2			/*
3			* trie_dict
4			* - trie-tree based dict feature
5			*
6	sysadm	1.27	* Copyright (C) 2004-2026 Leaflet <leaflet@leafok.com>
7	sysadm	1.13	*/
8	sysadm	1.1
9	sysadm	1.16	#ifdef HAVE_CONFIG_H
10			#include "config.h"
11			#endif
12
13	sysadm	1.20	#include "common.h"
14	sysadm	1.11	#include "log.h"
15	sysadm	1.1	#include "trie_dict.h"
16	sysadm	1.7	#include <errno.h>
17	sysadm	1.20	#include <fcntl.h>
18	sysadm	1.10	#include <stdio.h>
19	sysadm	1.1	#include <stdlib.h>
20	sysadm	1.10	#include <string.h>
21	sysadm	1.7	#include <time.h>
22			#include <unistd.h>
23	sysadm	1.20	#include <sys/mman.h>
24			#include <sys/stat.h>
25	sysadm	1.7
26			struct trie_node_pool_t
27			{
28	sysadm	1.20	size_t shm_size;
29	sysadm	1.8	int node_count_limit;
30			int node_count;
31	sysadm	1.7	TRIE_NODE *p_node_free_list;
32			};
33			typedef struct trie_node_pool_t TRIE_NODE_POOL;
34
35	sysadm	1.23	static char trie_node_shm_name[FILE_NAME_LEN];
36	sysadm	1.7	static TRIE_NODE_POOL *p_trie_node_pool;
37
38	sysadm	1.8	int trie_dict_init(const char *filename, int node_count_limit)
39	sysadm	1.7	{
40	sysadm	1.20	char filepath[FILE_PATH_LEN];
41			int fd;
42	sysadm	1.7	size_t size;
43			void *p_shm;
44	sysadm	1.8	TRIE_NODE *p_trie_nodes;
45	sysadm	1.7	int i;
46
47	sysadm	1.20	if (filename == NULL)
48			{
49	sysadm	1.25	log_error("NULL pointer error");
50	sysadm	1.20	return -1;
51			}
52
53	sysadm	1.7	if (p_trie_node_pool != NULL)
54			{
55	sysadm	1.25	log_error("trie_dict_pool already initialized");
56	sysadm	1.7	return -1;
57			}
58
59	sysadm	1.8	if (node_count_limit <= 0 \|\| node_count_limit > TRIE_NODE_PER_POOL)
60			{
61	sysadm	1.25	log_error("trie_dict_init(%d) error: invalid node_count_limit", node_count_limit);
62	sysadm	1.8	return -1;
63			}
64
65	sysadm	1.7	// Allocate shared memory
66	sysadm	1.20	size = sizeof(TRIE_NODE_POOL) + sizeof(TRIE_NODE) * (size_t)node_count_limit;
67
68			strncpy(filepath, filename, sizeof(filepath) - 1);
69			filepath[sizeof(filepath) - 1] = '\0';
70			snprintf(trie_node_shm_name, sizeof(trie_node_shm_name), "/TRIE_DICT_SHM_%s", basename(filepath));
71
72			if (shm_unlink(trie_node_shm_name) == -1 && errno != ENOENT)
73	sysadm	1.7	{
74	sysadm	1.25	log_error("shm_unlink(%s) error (%d)", trie_node_shm_name, errno);
75	sysadm	1.7	return -2;
76			}
77
78	sysadm	1.20	if ((fd = shm_open(trie_node_shm_name, O_CREAT \| O_EXCL \| O_RDWR, 0600)) == -1)
79			{
80	sysadm	1.25	log_error("shm_open(%s) error (%d)", trie_node_shm_name, errno);
81	sysadm	1.20	return -2;
82			}
83			if (ftruncate(fd, (off_t)size) == -1)
84			{
85	sysadm	1.25	log_error("ftruncate(size=%d) error (%d)", size, errno);
86	sysadm	1.20	close(fd);
87			return -2;
88			}
89
90			p_shm = mmap(NULL, size, PROT_READ \| PROT_WRITE, MAP_SHARED, fd, 0L);
91			if (p_shm == MAP_FAILED)
92	sysadm	1.7	{
93	sysadm	1.25	log_error("mmap() error (%d)", errno);
94	sysadm	1.20	close(fd);
95			return -2;
96	sysadm	1.7	}
97	sysadm	1.20
98			if (close(fd) < 0)
99	sysadm	1.7	{
100	sysadm	1.25	log_error("close(fd) error (%d)", errno);
101	sysadm	1.20	return -1;
102	sysadm	1.7	}
103
104			p_trie_node_pool = p_shm;
105	sysadm	1.20	p_trie_node_pool->shm_size = size;
106	sysadm	1.8	p_trie_node_pool->node_count_limit = node_count_limit;
107	sysadm	1.7	p_trie_node_pool->node_count = 0;
108
109	sysadm	1.12	p_trie_nodes = (TRIE_NODE )((char )p_shm + sizeof(TRIE_NODE_POOL));
110	sysadm	1.8	p_trie_node_pool->p_node_free_list = &(p_trie_nodes[0]);
111			for (i = 0; i < node_count_limit - 1; i++)
112	sysadm	1.7	{
113	sysadm	1.8	p_trie_nodes[i].p_nodes[0] = &(p_trie_nodes[i + 1]);
114	sysadm	1.7	}
115	sysadm	1.8	p_trie_nodes[node_count_limit - 1].p_nodes[0] = NULL;
116	sysadm	1.7
117			return 0;
118			}
119
120	sysadm	1.23	void trie_dict_cleanup(void)
121	sysadm	1.7	{
122			if (p_trie_node_pool == NULL)
123			{
124	sysadm	1.23	return;
125	sysadm	1.7	}
126
127			detach_trie_dict_shm();
128
129	sysadm	1.20	if (shm_unlink(trie_node_shm_name) == -1 && errno != ENOENT)
130	sysadm	1.7	{
131	sysadm	1.25	log_error("shm_unlink(%s) error (%d)", trie_node_shm_name, errno);
132	sysadm	1.7	}
133	sysadm	1.20
134			trie_node_shm_name[0] = '\0';
135	sysadm	1.7	}
136
137	sysadm	1.20	int set_trie_dict_shm_readonly(void)
138			{
139	sysadm	1.21	if (p_trie_node_pool != NULL && mprotect(p_trie_node_pool, p_trie_node_pool->shm_size, PROT_READ) < 0)
140	sysadm	1.20	{
141	sysadm	1.25	log_error("mprotect() error (%d)", errno);
142	sysadm	1.21	return -1;
143	sysadm	1.20	}
144	sysadm	1.7
145			return 0;
146			}
147
148			int detach_trie_dict_shm(void)
149			{
150	sysadm	1.20	if (p_trie_node_pool != NULL && munmap(p_trie_node_pool, p_trie_node_pool->shm_size) < 0)
151	sysadm	1.7	{
152	sysadm	1.25	log_error("munmap() error (%d)", errno);
153	sysadm	1.7	return -1;
154			}
155	sysadm	1.8
156	sysadm	1.7	p_trie_node_pool = NULL;
157
158			return 0;
159			}
160	sysadm	1.1
161			TRIE_NODE *trie_dict_create(void)
162			{
163	sysadm	1.7	TRIE_NODE *p_dict = NULL;
164
165			if (p_trie_node_pool != NULL && p_trie_node_pool->p_node_free_list != NULL)
166			{
167			p_dict = p_trie_node_pool->p_node_free_list;
168			p_trie_node_pool->p_node_free_list = p_dict->p_nodes[0];
169	sysadm	1.1
170	sysadm	1.10	memset(p_dict, 0, sizeof(*p_dict));
171	sysadm	1.8
172			p_trie_node_pool->node_count++;
173			}
174			else if (p_trie_node_pool != NULL)
175			{
176	sysadm	1.25	log_error("trie_dict_create() error: node depleted %d >= %d", p_trie_node_pool->node_count, p_trie_node_pool->node_count_limit);
177	sysadm	1.7	}
178	sysadm	1.1
179			return p_dict;
180			}
181
182			void trie_dict_destroy(TRIE_NODE *p_dict)
183			{
184	sysadm	1.7	if (p_trie_node_pool == NULL \|\| p_dict == NULL)
185	sysadm	1.1	{
186			return;
187			}
188
189			for (int i = 0; i < TRIE_CHILDREN; i++)
190			{
191			if (p_dict->p_nodes[i] != NULL)
192			{
193			trie_dict_destroy(p_dict->p_nodes[i]);
194			}
195	sysadm	1.7	}
196	sysadm	1.3
197	sysadm	1.10	memset(p_dict, 0, sizeof(*p_dict));
198	sysadm	1.1
199	sysadm	1.7	p_dict->p_nodes[0] = p_trie_node_pool->p_node_free_list;
200			p_trie_node_pool->p_node_free_list = p_dict;
201	sysadm	1.8
202			p_trie_node_pool->node_count--;
203	sysadm	1.1	}
204
205			int trie_dict_set(TRIE_NODE p_dict, const char key, int64_t value)
206			{
207			int offset;
208
209	sysadm	1.5	if (p_dict == NULL)
210			{
211			return -1;
212			}
213
214	sysadm	1.1	while (key != NULL && *key != '\0')
215			{
216	sysadm	1.26	offset = (unsigned char)(*key);
217	sysadm	1.3	if (offset < 0 \|\| offset >= TRIE_CHILDREN) // incorrect key character
218			{
219			return -1;
220			}
221	sysadm	1.1
222			if (*(key + 1) == '\0')
223			{
224			if (p_dict->flags[offset] == 0 \|\| p_dict->values[offset] != value)
225			{
226			p_dict->values[offset] = value;
227			p_dict->flags[offset] = 1;
228			return 1; // Set to new value
229			}
230			return 0; // Unchanged
231			}
232			else
233			{
234			if (p_dict->p_nodes[offset] == NULL)
235			{
236			if ((p_dict->p_nodes[offset] = trie_dict_create()) == NULL)
237			{
238			return -2; // OOM
239			}
240			}
241			p_dict = p_dict->p_nodes[offset];
242			key++;
243			}
244			}
245
246			return -1; // NULL key
247			}
248
249			int trie_dict_get(TRIE_NODE p_dict, const char key, int64_t *p_value)
250			{
251			int offset;
252
253	sysadm	1.5	if (p_dict == NULL)
254			{
255			return -1;
256			}
257
258	sysadm	1.1	while (key != NULL && *key != '\0')
259			{
260	sysadm	1.26	offset = (unsigned char)(*key);
261	sysadm	1.3	if (offset < 0 \|\| offset >= TRIE_CHILDREN) // incorrect key character
262			{
263			return -1;
264			}
265	sysadm	1.1
266			if (*(key + 1) == '\0')
267			{
268			if (p_dict->flags[offset] != 0)
269			{
270			*p_value = p_dict->values[offset];
271			return 1; // Found
272			}
273			else
274			{
275			return 0; // Not exist
276			}
277			}
278			else if (p_dict->p_nodes[offset] == NULL)
279			{
280			return 0; // Not exist
281			}
282			else
283			{
284			p_dict = p_dict->p_nodes[offset];
285			key++;
286			}
287			}
288
289			return -1; // NULL key
290			}
291
292			int trie_dict_del(TRIE_NODE p_dict, const char key)
293			{
294			int offset;
295
296	sysadm	1.5	if (p_dict == NULL)
297			{
298			return -1;
299			}
300
301	sysadm	1.1	while (key != NULL && *key != '\0')
302			{
303	sysadm	1.26	offset = (unsigned char)(*key);
304	sysadm	1.3	if (offset < 0 \|\| offset >= TRIE_CHILDREN) // incorrect key character
305			{
306			return -1;
307			}
308	sysadm	1.1
309			if (*(key + 1) == '\0')
310			{
311			if (p_dict->flags[offset] != 0)
312			{
313			p_dict->flags[offset] = 0;
314			p_dict->values[offset] = 0;
315			return 1; // Done
316			}
317			else
318			{
319			return 0; // Not exist
320			}
321			}
322			else if (p_dict->p_nodes[offset] == NULL)
323			{
324			return 0; // Not exist
325			}
326			else
327			{
328			p_dict = p_dict->p_nodes[offset];
329			key++;
330			}
331			}
332
333			return -1; // NULL key
334			}
335	sysadm	1.2
336			static void _trie_dict_traverse(TRIE_NODE p_dict, trie_dict_traverse_cb cb, char key, int depth)
337			{
338			if (p_dict == NULL \|\| depth >= TRIE_MAX_KEY_LEN)
339			{
340			return;
341			}
342
343			for (int i = 0; i < TRIE_CHILDREN; i++)
344			{
345			if (p_dict->flags[i] != 0)
346			{
347	sysadm	1.5	key[depth] = (char)i;
348	sysadm	1.3	key[depth + 1] = '\0';
349	sysadm	1.2	(*cb)(key, p_dict->values[i]);
350			}
351
352			if (p_dict->p_nodes[i] != NULL && depth + 1 < TRIE_MAX_KEY_LEN)
353			{
354	sysadm	1.5	key[depth] = (char)i;
355	sysadm	1.2	_trie_dict_traverse(p_dict->p_nodes[i], cb, key, depth + 1);
356			}
357	sysadm	1.5	}
358	sysadm	1.2	}
359
360			void trie_dict_traverse(TRIE_NODE *p_dict, trie_dict_traverse_cb cb)
361			{
362			char key[TRIE_MAX_KEY_LEN + 1];
363	sysadm	1.5
364			if (p_dict == NULL)
365			{
366			return;
367			}
368	sysadm	1.2
369			_trie_dict_traverse(p_dict, cb, key, 0);
370			}
371	sysadm	1.8
372			int trie_dict_used_nodes(void)
373			{
374			return (p_trie_node_pool == NULL ? -1 : p_trie_node_pool->node_count);
375			}
webmaster@leafok.com	ViewVC Help
Powered by ViewVC 1.3.0-beta1