1 /****************************************************************************
2 * Copyright (c) 2006-2010,2011 Free Software Foundation, Inc. *
4 * Permission is hereby granted, free of charge, to any person obtaining a *
5 * copy of this software and associated documentation files (the *
6 * "Software"), to deal in the Software without restriction, including *
7 * without limitation the rights to use, copy, modify, merge, publish, *
8 * distribute, distribute with modifications, sublicense, and/or sell *
9 * copies of the Software, and to permit persons to whom the Software is *
10 * furnished to do so, subject to the following conditions: *
12 * The above copyright notice and this permission notice shall be included *
13 * in all copies or substantial portions of the Software. *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS *
16 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF *
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. *
18 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
19 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR *
20 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR *
21 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. *
23 * Except as contained in this notice, the name(s) of the above copyright *
24 * holders shall not be used in advertising or otherwise to promote the *
25 * sale, use or other dealings in this Software without prior written *
27 ****************************************************************************/
29 /****************************************************************************
30 * Author: Thomas E. Dickey *
31 ****************************************************************************/
34 * Iterators for terminal databases.
37 #include <curses.priv.h>
43 #include <hashed_db.h>
46 MODULE_ID("$Id: db_iterator.c,v 1.18 2011/09/26 09:52:00 tom Exp $")
48 #define HaveTicDirectory _nc_globals.have_tic_directory
49 #define KeepTicDirectory _nc_globals.keep_tic_directory
50 #define TicDirectory _nc_globals.tic_directory
53 * FIXME: need a no-leaks entrypoint.
55 static char *my_blob; /* string-heap for my_list[] */
56 static char **my_list; /* distinct places to look for data */
57 static int my_size; /* length of my_list[] */
58 static time_t my_time; /* cache last updated */
65 add_to_blob(const char *text)
68 char *last = my_blob + strlen(my_blob);
76 check_existence(const char *name, struct stat *sb)
80 if (stat(name, sb) == 0 && sb->st_size) {
84 else if (strlen(name) < PATH_MAX - sizeof(DBM_SUFFIX)) {
86 sprintf(temp, "%s%s", name, DBM_SUFFIX);
87 if (stat(temp, sb) == 0 && sb->st_size) {
97 * Store the latest value of an environment variable in my_vars[] so we can
98 * detect if one changes, invalidating the cached search-list.
101 update_getenv(const char *name, DBDIRS which)
104 char *value = getenv(name);
106 if (which < dbdLAST) {
107 if (my_vars[which].name == 0 || strcmp(my_vars[which].name, name)) {
108 FreeIfNeeded(my_vars[which].value);
109 my_vars[which].name = name;
110 my_vars[which].value = value;
112 } else if ((my_vars[which].value != 0) ^ (value != 0)) {
113 FreeIfNeeded(my_vars[which].value);
114 my_vars[which].value = value;
116 } else if (value != 0 && strcmp(value, my_vars[which].value)) {
117 FreeIfNeeded(my_vars[which].value);
118 my_vars[which].value = value;
126 cache_getenv(const char *name, DBDIRS which)
130 (void) update_getenv(name, which);
131 if (which < dbdLAST) {
132 result = my_vars[which].value;
138 * The cache expires if at least a second has passed since the initial lookup,
139 * or if one of the environment variables changed.
141 * Only a few applications use multiple lookups of terminal entries, seems that
142 * aside from bulk I/O such as tic and toe, that leaves interactive programs
143 * which should not be modifying the terminal databases in a way that would
144 * invalidate the search-list.
146 * The "1-second" is to allow for user-directed changes outside the program.
152 time_t now = time((time_t *) 0);
158 for (n = 0; n < dbdLAST; ++n) {
159 if (my_vars[n].name != 0
160 && update_getenv(my_vars[n].name, n)) {
172 FreeAndNull(my_blob);
173 FreeAndNull(my_list);
177 * Record the "official" location of the terminfo directory, according to
178 * the place where we're writing to, or the normal default, if not.
180 NCURSES_EXPORT(const char *)
181 _nc_tic_dir(const char *path)
183 T(("_nc_tic_dir %s", NonNull(path)));
184 if (!KeepTicDirectory) {
187 HaveTicDirectory = TRUE;
188 } else if (!HaveTicDirectory && use_terminfo_vars()) {
190 if ((envp = getenv("TERMINFO")) != 0)
191 return _nc_tic_dir(envp);
198 * Special fix to prevent the terminfo directory from being moved after tic
199 * has chdir'd to it. If we let it be changed, then if $TERMINFO has a
200 * relative path, we'll lose track of the actual directory.
203 _nc_keep_tic_dir(const char *path)
206 KeepTicDirectory = TRUE;
215 if (my_blob != 0 && cache_expired()) {
221 * This is a simple iterator which allows the caller to step through the
222 * possible locations for a terminfo directory. ncurses uses this to find
223 * terminfo files to read.
225 NCURSES_EXPORT(const char *)
226 _nc_next_db(DBDIRS * state, int *offset)
231 if ((int) *state < my_size
233 && my_list[*state] != 0) {
234 result = my_list[*state];
240 T(("_nc_next_db %d %s", *state, result));
246 _nc_first_db(DBDIRS * state, int *offset)
253 /* build a blob containing all of the strings we will use for a lookup
258 const char *values[dbdLAST];
259 struct stat *my_stat;
262 for (j = 0; j < dbdLAST; ++j)
266 * This is the first item in the list, and is used only when tic is
267 * writing to the database, as a performance improvement.
269 values[dbdTIC] = TicDirectory;
273 values[dbdCfgList] = TERMINFO_DIRS;
276 values[dbdCfgOnce] = TERMINFO;
281 values[dbdCfgList2] = TERMPATH;
284 if (use_terminfo_vars()) {
286 values[dbdEnvOnce] = cache_getenv("TERMINFO", dbdEnvOnce);
287 values[dbdHome] = _nc_home_terminfo();
288 (void) cache_getenv("HOME", dbdHome);
289 values[dbdEnvList] = cache_getenv("TERMINFO_DIRS", dbdEnvList);
292 values[dbdEnvOnce2] = cache_getenv("TERMCAP", dbdEnvOnce2);
293 values[dbdEnvList2] = cache_getenv("TERMPATH", dbdEnvList2);
294 #endif /* USE_TERMCAP */
297 for (j = 0; j < dbdLAST; ++j) {
300 blobsize += 2 + strlen(values[j]);
303 my_blob = malloc(blobsize);
306 for (j = 0; j < dbdLAST; ++j) {
307 add_to_blob(values[j]);
310 /* Now, build an array which will be pointers to the distinct
311 * strings in the blob.
314 for (j = 0; my_blob[j] != '\0'; ++j) {
315 if (my_blob[j] == ':')
318 my_list = typeCalloc(char *, blobsize);
319 my_stat = typeCalloc(struct stat, blobsize);
320 if (my_list != 0 && my_stat != 0) {
322 my_list[k++] = my_blob;
323 for (j = 0; my_blob[j] != '\0'; ++j) {
324 if (my_blob[j] == ':') {
326 my_list[k++] = &my_blob[j + 1];
331 * Eliminate duplicates from the list.
333 for (j = 0; my_list[j] != 0; ++j) {
335 if (*my_list[j] == '\0')
336 my_list[j] = TERMINFO;
338 for (k = 0; k < j; ++k) {
339 if (!strcmp(my_list[j], my_list[k])) {
341 while ((my_list[j] = my_list[j + 1]) != 0) {
351 * Eliminate non-existent databases, and those that happen to
352 * be symlinked to another location.
354 for (j = 0; my_list[j] != 0; ++j) {
355 bool found = check_existence(my_list[j], &my_stat[j]);
358 for (k = 0; k < j; ++k) {
359 if (my_stat[j].st_dev == my_stat[k].st_dev
360 && my_stat[j].st_ino == my_stat[k].st_ino) {
369 while ((my_list[k] = my_list[k + 1]) != 0) {
376 my_time = time((time_t *) 0);
378 FreeAndNull(my_blob);