1 /****************************************************************************
2 * Copyright 2019-2024,2025 Thomas E. Dickey *
3 * Copyright 2006-2011,2013 Free Software Foundation, Inc. *
4 * *
5 * Permission is hereby granted, free of charge, to any person obtaining a *
6 * copy of this software and associated documentation files (the *
7 * "Software"), to deal in the Software without restriction, including *
8 * without limitation the rights to use, copy, modify, merge, publish, *
9 * distribute, distribute with modifications, sublicense, and/or sell *
10 * copies of the Software, and to permit persons to whom the Software is *
11 * furnished to do so, subject to the following conditions: *
12 * *
13 * The above copyright notice and this permission notice shall be included *
14 * in all copies or substantial portions of the Software. *
15 * *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
19 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
20 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
21 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
22 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
23 * *
24 * Except as contained in this notice, the name(s) of the above copyright *
25 * holders shall not be used in advertising or otherwise to promote the *
26 * sale, use or other dealings in this Software without prior written *
27 * authorization. *
28 ****************************************************************************/
29
30 /****************************************************************************
31 * Author: Thomas E. Dickey 2006-on *
32 ****************************************************************************/
33
34 #include <curses.priv.h>
35 #include <tic.h>
36 #include <hashed_db.h>
37
38 #if USE_HASHED_DB
39
40 MODULE_ID("$Id: hashed_db.c,v 1.22 2025/01/11 23:52:18 tom Exp $")
41
42 #if HASHED_DB_API >= 2
43 static DBC *cursor;
44 #endif
45
46 typedef struct _myconn {
47 struct _myconn *next;
48 DB *db;
49 char *path;
50 bool modify;
51 } MYCONN;
52
53 static MYCONN *connections;
54
55 static void
cleanup(void)56 cleanup(void)
57 {
58 while (connections != NULL) {
59 _nc_db_close(connections->db);
60 }
61 }
62
63 static DB *
find_connection(const char * path,bool modify)64 find_connection(const char *path, bool modify)
65 {
66 DB *result = NULL;
67 MYCONN *p;
68
69 for (p = connections; p != NULL; p = p->next) {
70 if (!strcmp(p->path, path) && p->modify == modify) {
71 result = p->db;
72 break;
73 }
74 }
75
76 return result;
77 }
78
79 static void
drop_connection(DB * db)80 drop_connection(DB * db)
81 {
82 MYCONN *p, *q;
83
84 for (p = connections, q = NULL; p != NULL; q = p, p = p->next) {
85 if (p->db == db) {
86 if (q != NULL)
87 q->next = p->next;
88 else
89 connections = p->next;
90 free(p->path);
91 free(p);
92 break;
93 }
94 }
95 }
96
97 static bool
make_connection(DB * db,const char * path,bool modify)98 make_connection(DB * db, const char *path, bool modify)
99 {
100 bool code = FALSE;
101 MYCONN *p = typeCalloc(MYCONN, 1);
102
103 if (p != NULL) {
104 p->path = strdup(path);
105 if (p->path != NULL) {
106 p->db = db;
107 p->modify = modify;
108 p->next = connections;
109 connections = p;
110 code = TRUE;
111 } else {
112 free(p);
113 }
114 }
115 return code;
116 }
117
118 /*
119 * Open the database.
120 */
121 NCURSES_EXPORT(DB *)
_nc_db_open(const char * path,bool modify)122 _nc_db_open(const char *path, bool modify)
123 {
124 DB *result = NULL;
125 int code;
126
127 if (connections == NULL)
128 atexit(cleanup);
129
130 if ((result = find_connection(path, modify)) == NULL) {
131
132 #if HASHED_DB_API >= 4
133 db_create(&result, NULL, 0);
134 if ((code = result->open(result,
135 NULL,
136 path,
137 NULL,
138 DB_HASH,
139 modify ? DB_CREATE : DB_RDONLY,
140 0644)) != 0) {
141 result = NULL;
142 }
143 #elif HASHED_DB_API >= 3
144 db_create(&result, NULL, 0);
145 if ((code = result->open(result,
146 path,
147 NULL,
148 DB_HASH,
149 modify ? DB_CREATE : DB_RDONLY,
150 0644)) != 0) {
151 result = NULL;
152 }
153 #elif HASHED_DB_API >= 2
154 if ((code = db_open(path,
155 DB_HASH,
156 modify ? DB_CREATE : DB_RDONLY,
157 0644,
158 (DB_ENV *) 0,
159 (DB_INFO *) 0,
160 &result)) != 0) {
161 result = NULL;
162 }
163 #else
164 if ((result = dbopen(path,
165 modify ? (O_CREAT | O_RDWR) : O_RDONLY,
166 0644,
167 DB_HASH,
168 NULL)) == NULL) {
169 code = errno;
170 } else {
171 code = 0;
172 }
173 #endif
174 if (result != NULL && make_connection(result, path, modify)) {
175 T(("opened %s", path));
176 } else {
177 T(("cannot open %s: (errno %d) %s", path, code, strerror(code)));
178 errno = code;
179 }
180 }
181 return result;
182 }
183
184 /*
185 * Close the database. Do not attempt to use the 'db' handle after this call.
186 */
187 NCURSES_EXPORT(int)
_nc_db_close(DB * db)188 _nc_db_close(DB * db)
189 {
190 int result;
191
192 drop_connection(db);
193 #if HASHED_DB_API >= 2
194 result = db->close(db, 0);
195 #else
196 result = db->close(db);
197 #endif
198 return result;
199 }
200
201 /*
202 * Write a record to the database.
203 *
204 * Returns 0 on success.
205 *
206 * FIXME: the FreeBSD cap_mkdb program assumes the database could have
207 * duplicates. There appears to be no good reason for that (review/fix).
208 */
209 NCURSES_EXPORT(int)
_nc_db_put(DB * db,DBT * key,DBT * data)210 _nc_db_put(DB * db, DBT * key, DBT * data)
211 {
212 int result;
213 #if HASHED_DB_API >= 2
214 /* remove any pre-existing value, since we do not want duplicates */
215 (void) db->del(db, NULL, key, 0);
216 result = db->put(db, NULL, key, data, DB_NOOVERWRITE);
217 #else
218 result = db->put(db, key, data, R_NOOVERWRITE);
219 #endif
220 return result;
221 }
222
223 /*
224 * Read a record from the database.
225 *
226 * Returns 0 on success.
227 */
228 NCURSES_EXPORT(int)
_nc_db_get(DB * db,DBT * key,DBT * data)229 _nc_db_get(DB * db, DBT * key, DBT * data)
230 {
231 int result;
232
233 memset(data, 0, sizeof(*data));
234 #if HASHED_DB_API >= 2
235 result = db->get(db, NULL, key, data, 0);
236 #else
237 result = db->get(db, key, data, 0);
238 #endif
239 return result;
240 }
241
242 /*
243 * Read the first record from the database, ignoring order.
244 *
245 * Returns 0 on success.
246 */
247 NCURSES_EXPORT(int)
_nc_db_first(DB * db,DBT * key,DBT * data)248 _nc_db_first(DB * db, DBT * key, DBT * data)
249 {
250 int result;
251
252 memset(key, 0, sizeof(*key));
253 memset(data, 0, sizeof(*data));
254 #if HASHED_DB_API >= 2
255 if ((result = db->cursor(db, NULL, &cursor, 0)) == 0) {
256 result = cursor->c_get(cursor, key, data, DB_FIRST);
257 }
258 #else
259 result = db->seq(db, key, data, 0);
260 #endif
261 return result;
262 }
263
264 /*
265 * Read the next record from the database, ignoring order.
266 *
267 * Returns 0 on success.
268 */
269 NCURSES_EXPORT(int)
_nc_db_next(DB * db,DBT * key,DBT * data)270 _nc_db_next(DB * db, DBT * key, DBT * data)
271 {
272 int result;
273
274 #if HASHED_DB_API >= 2
275 (void) db;
276 if (cursor != 0) {
277 result = cursor->c_get(cursor, key, data, DB_NEXT);
278 } else {
279 result = -1;
280 }
281 #else
282 result = db->seq(db, key, data, R_NEXT);
283 #endif
284 return result;
285 }
286
287 /*
288 * Check if a record is a terminfo index record. Index records are those that
289 * contain only an alias pointing to a list of aliases.
290 */
291 NCURSES_EXPORT(bool)
_nc_db_have_index(DBT * key,DBT * data,char ** buffer,int * size)292 _nc_db_have_index(DBT * key, DBT * data, char **buffer, int *size)
293 {
294 bool result = FALSE;
295 int used = (int) data->size - 1;
296 char *have = (char *) data->data;
297
298 (void) key;
299 if (*have++ == 2) {
300 result = TRUE;
301 }
302 /*
303 * Update params in any case for consistency with _nc_db_have_data().
304 */
305 *buffer = have;
306 *size = used;
307 return result;
308 }
309
310 /*
311 * Check if a record is the terminfo data record. Ignore index records, e.g.,
312 * those that contain only an alias pointing to a list of aliases.
313 */
314 NCURSES_EXPORT(bool)
_nc_db_have_data(DBT * key,DBT * data,char ** buffer,int * size)315 _nc_db_have_data(DBT * key, DBT * data, char **buffer, int *size)
316 {
317 bool result = FALSE;
318 int used = (int) data->size - 1;
319 char *have = (char *) data->data;
320
321 if (*have++ == 0) {
322 if (data->size > key->size
323 && IS_TIC_MAGIC(have)) {
324 result = TRUE;
325 }
326 }
327 /*
328 * Update params in any case to make it simple to follow a index record
329 * to the data record.
330 */
331 *buffer = have;
332 *size = used;
333 return result;
334 }
335
336 #else
337
338 extern
339 NCURSES_EXPORT(void)
340 _nc_hashed_db(void);
341
342 NCURSES_EXPORT(void)
_nc_hashed_db(void)343 _nc_hashed_db(void)
344 {
345 }
346
347 #endif /* USE_HASHED_DB */
348