lbbs/src/trie_dict.c

/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
 * trie_dict
 *   - trie-tree based dict feature
 *
 * Copyright (C) 2004-2025  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\n");
                return -1;
        }

        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
        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)\n", 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)\n", trie_node_shm_name, errno);
                return -2;
        }
        if (ftruncate(fd, (off_t)size) == -1)
        {
                log_error("ftruncate(size=%d) error (%d)\n", 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)\n", errno);
                close(fd);
                return -2;
        }

        if (close(fd) < 0)
        {
                log_error("close(fd) error (%d)\n", 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)\n", trie_node_shm_name, errno);
        }

        trie_node_shm_name[0] = '\0';
}

int get_trie_dict_shm_readonly(void)
{
        int fd;
        struct stat sb;
        size_t size;
        void *p_shm;

        if ((fd = shm_open(trie_node_shm_name, O_RDONLY, 0600)) == -1)
        {
                log_error("shm_open(%s) error (%d)\n", trie_node_shm_name, errno);
                return -2;
        }

        if (fstat(fd, &sb) < 0)
        {
                log_error("fstat(fd) error (%d)\n", errno);
                close(fd);
                return -2;
        }

        size = (size_t)sb.st_size;

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

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

        if (p_trie_node_pool->shm_size != size)
        {
                log_error("Shared memory size mismatch (%ld != %ld)\n", p_trie_node_pool->shm_size, size);
                munmap(p_shm, size);
                return -3;
        }

        p_trie_node_pool = p_shm;

        return 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)\n", 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)\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];

                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\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]);
                }
        }

        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 = (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	/* SPDX-License-Identifier: GPL-3.0-or-later */
2	/*
3	* trie_dict
4	* - trie-tree based dict feature
5	*
6	* Copyright (C) 2004-2025 Leaflet <leaflet@leafok.com>
7	*/
8
9	#ifdef HAVE_CONFIG_H
10	#include "config.h"
11	#endif
12
13	#include "common.h"
14	#include "log.h"
15	#include "trie_dict.h"
16	#include <errno.h>
17	#include <fcntl.h>
18	#include <stdio.h>
19	#include <stdlib.h>
20	#include <string.h>
21	#include <time.h>
22	#include <unistd.h>
23	#include <sys/mman.h>
24	#include <sys/stat.h>
25
26	struct trie_node_pool_t
27	{
28	size_t shm_size;
29	int node_count_limit;
30	int node_count;
31	TRIE_NODE *p_node_free_list;
32	};
33	typedef struct trie_node_pool_t TRIE_NODE_POOL;
34
35	static char trie_node_shm_name[FILE_NAME_LEN];
36	static TRIE_NODE_POOL *p_trie_node_pool;
37
38	int trie_dict_init(const char *filename, int node_count_limit)
39	{
40	char filepath[FILE_PATH_LEN];
41	int fd;
42	size_t size;
43	void *p_shm;
44	TRIE_NODE *p_trie_nodes;
45	int i;
46
47	if (filename == NULL)
48	{
49	log_error("NULL pointer error\n");
50	return -1;
51	}
52
53	if (p_trie_node_pool != NULL)
54	{
55	log_error("trie_dict_pool already initialized\n");
56	return -1;
57	}
58
59	if (node_count_limit <= 0 \|\| node_count_limit > TRIE_NODE_PER_POOL)
60	{
61	log_error("trie_dict_init(%d) error: invalid node_count_limit\n", node_count_limit);
62	return -1;
63	}
64
65	// Allocate shared memory
66	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	{
74	log_error("shm_unlink(%s) error (%d)\n", trie_node_shm_name, errno);
75	return -2;
76	}
77
78	if ((fd = shm_open(trie_node_shm_name, O_CREAT \| O_EXCL \| O_RDWR, 0600)) == -1)
79	{
80	log_error("shm_open(%s) error (%d)\n", trie_node_shm_name, errno);
81	return -2;
82	}
83	if (ftruncate(fd, (off_t)size) == -1)
84	{
85	log_error("ftruncate(size=%d) error (%d)\n", size, errno);
86	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	{
93	log_error("mmap() error (%d)\n", errno);
94	close(fd);
95	return -2;
96	}
97
98	if (close(fd) < 0)
99	{
100	log_error("close(fd) error (%d)\n", errno);
101	return -1;
102	}
103
104	p_trie_node_pool = p_shm;
105	p_trie_node_pool->shm_size = size;
106	p_trie_node_pool->node_count_limit = node_count_limit;
107	p_trie_node_pool->node_count = 0;
108
109	p_trie_nodes = (TRIE_NODE )((char )p_shm + sizeof(TRIE_NODE_POOL));
110	p_trie_node_pool->p_node_free_list = &(p_trie_nodes[0]);
111	for (i = 0; i < node_count_limit - 1; i++)
112	{
113	p_trie_nodes[i].p_nodes[0] = &(p_trie_nodes[i + 1]);
114	}
115	p_trie_nodes[node_count_limit - 1].p_nodes[0] = NULL;
116
117	return 0;
118	}
119
120	void trie_dict_cleanup(void)
121	{
122	if (p_trie_node_pool == NULL)
123	{
124	return;
125	}
126
127	detach_trie_dict_shm();
128
129	if (shm_unlink(trie_node_shm_name) == -1 && errno != ENOENT)
130	{
131	log_error("shm_unlink(%s) error (%d)\n", trie_node_shm_name, errno);
132	}
133
134	trie_node_shm_name[0] = '\0';
135	}
136
137	int get_trie_dict_shm_readonly(void)
138	{
139	int fd;
140	struct stat sb;
141	size_t size;
142	void *p_shm;
143
144	if ((fd = shm_open(trie_node_shm_name, O_RDONLY, 0600)) == -1)
145	{
146	log_error("shm_open(%s) error (%d)\n", trie_node_shm_name, errno);
147	return -2;
148	}
149
150	if (fstat(fd, &sb) < 0)
151	{
152	log_error("fstat(fd) error (%d)\n", errno);
153	close(fd);
154	return -2;
155	}
156
157	size = (size_t)sb.st_size;
158
159	p_shm = mmap(NULL, size, PROT_READ, MAP_SHARED, fd, 0L);
160	if (p_shm == MAP_FAILED)
161	{
162	log_error("mmap() error (%d)\n", errno);
163	close(fd);
164	return -2;
165	}
166
167	if (close(fd) < 0)
168	{
169	log_error("close(fd) error (%d)\n", errno);
170	return -1;
171	}
172
173	if (p_trie_node_pool->shm_size != size)
174	{
175	log_error("Shared memory size mismatch (%ld != %ld)\n", p_trie_node_pool->shm_size, size);
176	munmap(p_shm, size);
177	return -3;
178	}
179
180	p_trie_node_pool = p_shm;
181
182	return 0;
183	}
184
185	int set_trie_dict_shm_readonly(void)
186	{
187	if (p_trie_node_pool != NULL && mprotect(p_trie_node_pool, p_trie_node_pool->shm_size, PROT_READ) < 0)
188	{
189	log_error("mprotect() error (%d)\n", errno);
190	return -1;
191	}
192
193	return 0;
194	}
195
196	int detach_trie_dict_shm(void)
197	{
198	if (p_trie_node_pool != NULL && munmap(p_trie_node_pool, p_trie_node_pool->shm_size) < 0)
199	{
200	log_error("munmap() error (%d)\n", errno);
201	return -1;
202	}
203
204	p_trie_node_pool = NULL;
205
206	return 0;
207	}
208
209	TRIE_NODE *trie_dict_create(void)
210	{
211	TRIE_NODE *p_dict = NULL;
212
213	if (p_trie_node_pool != NULL && p_trie_node_pool->p_node_free_list != NULL)
214	{
215	p_dict = p_trie_node_pool->p_node_free_list;
216	p_trie_node_pool->p_node_free_list = p_dict->p_nodes[0];
217
218	memset(p_dict, 0, sizeof(*p_dict));
219
220	p_trie_node_pool->node_count++;
221	}
222	else if (p_trie_node_pool != NULL)
223	{
224	log_error("trie_dict_create() error: node depleted %d >= %d\n", p_trie_node_pool->node_count, p_trie_node_pool->node_count_limit);
225	}
226
227	return p_dict;
228	}
229
230	void trie_dict_destroy(TRIE_NODE *p_dict)
231	{
232	if (p_trie_node_pool == NULL \|\| p_dict == NULL)
233	{
234	return;
235	}
236
237	for (int i = 0; i < TRIE_CHILDREN; i++)
238	{
239	if (p_dict->p_nodes[i] != NULL)
240	{
241	trie_dict_destroy(p_dict->p_nodes[i]);
242	}
243	}
244
245	memset(p_dict, 0, sizeof(*p_dict));
246
247	p_dict->p_nodes[0] = p_trie_node_pool->p_node_free_list;
248	p_trie_node_pool->p_node_free_list = p_dict;
249
250	p_trie_node_pool->node_count--;
251	}
252
253	int trie_dict_set(TRIE_NODE p_dict, const char key, int64_t value)
254	{
255	int offset;
256
257	if (p_dict == NULL)
258	{
259	return -1;
260	}
261
262	while (key != NULL && *key != '\0')
263	{
264	offset = (256 + *key) % 256;
265	if (offset < 0 \|\| offset >= TRIE_CHILDREN) // incorrect key character
266	{
267	return -1;
268	}
269
270	if (*(key + 1) == '\0')
271	{
272	if (p_dict->flags[offset] == 0 \|\| p_dict->values[offset] != value)
273	{
274	p_dict->values[offset] = value;
275	p_dict->flags[offset] = 1;
276	return 1; // Set to new value
277	}
278	return 0; // Unchanged
279	}
280	else
281	{
282	if (p_dict->p_nodes[offset] == NULL)
283	{
284	if ((p_dict->p_nodes[offset] = trie_dict_create()) == NULL)
285	{
286	return -2; // OOM
287	}
288	}
289	p_dict = p_dict->p_nodes[offset];
290	key++;
291	}
292	}
293
294	return -1; // NULL key
295	}
296
297	int trie_dict_get(TRIE_NODE p_dict, const char key, int64_t *p_value)
298	{
299	int offset;
300
301	if (p_dict == NULL)
302	{
303	return -1;
304	}
305
306	while (key != NULL && *key != '\0')
307	{
308	offset = (256 + *key) % 256;
309	if (offset < 0 \|\| offset >= TRIE_CHILDREN) // incorrect key character
310	{
311	return -1;
312	}
313
314	if (*(key + 1) == '\0')
315	{
316	if (p_dict->flags[offset] != 0)
317	{
318	*p_value = p_dict->values[offset];
319	return 1; // Found
320	}
321	else
322	{
323	return 0; // Not exist
324	}
325	}
326	else if (p_dict->p_nodes[offset] == NULL)
327	{
328	return 0; // Not exist
329	}
330	else
331	{
332	p_dict = p_dict->p_nodes[offset];
333	key++;
334	}
335	}
336
337	return -1; // NULL key
338	}
339
340	int trie_dict_del(TRIE_NODE p_dict, const char key)
341	{
342	int offset;
343
344	if (p_dict == NULL)
345	{
346	return -1;
347	}
348
349	while (key != NULL && *key != '\0')
350	{
351	offset = (256 + *key) % 256;
352	if (offset < 0 \|\| offset >= TRIE_CHILDREN) // incorrect key character
353	{
354	return -1;
355	}
356
357	if (*(key + 1) == '\0')
358	{
359	if (p_dict->flags[offset] != 0)
360	{
361	p_dict->flags[offset] = 0;
362	p_dict->values[offset] = 0;
363	return 1; // Done
364	}
365	else
366	{
367	return 0; // Not exist
368	}
369	}
370	else if (p_dict->p_nodes[offset] == NULL)
371	{
372	return 0; // Not exist
373	}
374	else
375	{
376	p_dict = p_dict->p_nodes[offset];
377	key++;
378	}
379	}
380
381	return -1; // NULL key
382	}
383
384	static void _trie_dict_traverse(TRIE_NODE p_dict, trie_dict_traverse_cb cb, char key, int depth)
385	{
386	if (p_dict == NULL \|\| depth >= TRIE_MAX_KEY_LEN)
387	{
388	return;
389	}
390
391	for (int i = 0; i < TRIE_CHILDREN; i++)
392	{
393	if (p_dict->flags[i] != 0)
394	{
395	key[depth] = (char)i;
396	key[depth + 1] = '\0';
397	(*cb)(key, p_dict->values[i]);
398	}
399
400	if (p_dict->p_nodes[i] != NULL && depth + 1 < TRIE_MAX_KEY_LEN)
401	{
402	key[depth] = (char)i;
403	_trie_dict_traverse(p_dict->p_nodes[i], cb, key, depth + 1);
404	}
405	}
406	}
407
408	void trie_dict_traverse(TRIE_NODE *p_dict, trie_dict_traverse_cb cb)
409	{
410	char key[TRIE_MAX_KEY_LEN + 1];
411
412	if (p_dict == NULL)
413	{
414	return;
415	}
416
417	_trie_dict_traverse(p_dict, cb, key, 0);
418	}
419
420	int trie_dict_used_nodes(void)
421	{
422	return (p_trie_node_pool == NULL ? -1 : p_trie_node_pool->node_count);
423	}
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