1 /****************************************************************************
2  * Copyright 2018-2019,2020 Thomas E. Dickey                                *
3  * Copyright 1998-2013,2017 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      *
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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               *
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21  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
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23  *                                                                          *
24  * Except as contained in this notice, the name(s) of the above copyright   *
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28  ****************************************************************************/
29 
30 /****************************************************************************
31  *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
32  *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
33  *     and: Thomas E. Dickey                        1996-on                 *
34  ****************************************************************************/
35 
36 /*
37  * alloc_entry.c -- allocation functions for terminfo entries
38  *
39  *	_nc_copy_entry()
40  *	_nc_init_entry()
41  *	_nc_merge_entry()
42  *	_nc_save_str()
43  *	_nc_wrap_entry()
44  *
45  */
46 
47 #include <curses.priv.h>
48 
49 #include <tic.h>
50 
51 MODULE_ID("$Id: alloc_entry.c,v 1.64 2020/02/02 23:34:34 tom Exp $")
52 
53 #define ABSENT_OFFSET    -1
54 #define CANCELLED_OFFSET -2
55 
56 #define MAX_STRTAB	4096	/* documented maximum entry size */
57 
58 static char *stringbuf;		/* buffer for string capabilities */
59 static size_t next_free;	/* next free character in stringbuf */
60 
61 NCURSES_EXPORT(void)
62 _nc_init_entry(ENTRY * const tp)
63 /* initialize a terminal type data block */
64 {
65 #if NO_LEAKS
66     if (tp == 0) {
67 	if (stringbuf != 0) {
68 	    FreeAndNull(stringbuf);
69 	}
70 	return;
71     }
72 #endif
73 
74     if (stringbuf == 0)
75 	TYPE_MALLOC(char, (size_t) MAX_STRTAB, stringbuf);
76 
77     next_free = 0;
78 
79     _nc_init_termtype(&(tp->tterm));
80 }
81 
82 NCURSES_EXPORT(ENTRY *)
83 _nc_copy_entry(ENTRY * oldp)
84 {
85     ENTRY *newp = typeCalloc(ENTRY, 1);
86 
87     if (newp != 0) {
88 	*newp = *oldp;
89 	_nc_copy_termtype2(&(newp->tterm), &(oldp->tterm));
90     }
91     return newp;
92 }
93 
94 /* save a copy of string in the string buffer */
95 NCURSES_EXPORT(char *)
96 _nc_save_str(const char *const string)
97 {
98     char *result = 0;
99     size_t old_next_free = next_free;
100     size_t len;
101 
102     if (!VALID_STRING(string))
103 	return _nc_save_str("");
104     len = strlen(string) + 1;
105 
106     if (len == 1 && next_free != 0) {
107 	/*
108 	 * Cheat a little by making an empty string point to the end of the
109 	 * previous string.
110 	 */
111 	if (next_free < MAX_STRTAB) {
112 	    result = (stringbuf + next_free - 1);
113 	}
114     } else if (next_free + len < MAX_STRTAB) {
115 	_nc_STRCPY(&stringbuf[next_free], string, MAX_STRTAB);
116 	DEBUG(7, ("Saved string %s", _nc_visbuf(string)));
117 	DEBUG(7, ("at location %d", (int) next_free));
118 	next_free += len;
119 	result = (stringbuf + old_next_free);
120     } else {
121 	_nc_warning("Too much data, some is lost: %s", string);
122     }
123     return result;
124 }
125 
126 NCURSES_EXPORT(void)
127 _nc_wrap_entry(ENTRY * const ep, bool copy_strings)
128 /* copy the string parts to allocated storage, preserving pointers to it */
129 {
130     int offsets[MAX_ENTRY_SIZE / sizeof(short)];
131     int useoffsets[MAX_USES];
132     unsigned i, n;
133     unsigned nuses = ep->nuses;
134     TERMTYPE2 *tp = &(ep->tterm);
135 
136     if (copy_strings) {
137 	next_free = 0;		/* clear static storage */
138 
139 	/* copy term_names, Strings, uses */
140 	tp->term_names = _nc_save_str(tp->term_names);
141 	for_each_string(i, tp) {
142 	    if (tp->Strings[i] != ABSENT_STRING &&
143 		tp->Strings[i] != CANCELLED_STRING) {
144 		tp->Strings[i] = _nc_save_str(tp->Strings[i]);
145 	    }
146 	}
147 
148 	for (i = 0; i < nuses; i++) {
149 	    if (ep->uses[i].name == 0) {
150 		ep->uses[i].name = _nc_save_str(ep->uses[i].name);
151 	    }
152 	}
153 
154 	free(tp->str_table);
155     }
156 
157     assert(tp->term_names >= stringbuf);
158     n = (unsigned) (tp->term_names - stringbuf);
159     for_each_string(i, &(ep->tterm)) {
160 	if (i < SIZEOF(offsets)) {
161 	    if (tp->Strings[i] == ABSENT_STRING) {
162 		offsets[i] = ABSENT_OFFSET;
163 	    } else if (tp->Strings[i] == CANCELLED_STRING) {
164 		offsets[i] = CANCELLED_OFFSET;
165 	    } else {
166 		offsets[i] = (int) (tp->Strings[i] - stringbuf);
167 	    }
168 	}
169     }
170 
171     for (i = 0; i < nuses; i++) {
172 	if (ep->uses[i].name == 0)
173 	    useoffsets[i] = ABSENT_OFFSET;
174 	else
175 	    useoffsets[i] = (int) (ep->uses[i].name - stringbuf);
176     }
177 
178     TYPE_MALLOC(char, next_free, tp->str_table);
179     (void) memcpy(tp->str_table, stringbuf, next_free);
180 
181     tp->term_names = tp->str_table + n;
182     for_each_string(i, &(ep->tterm)) {
183 	if (i < SIZEOF(offsets)) {
184 	    if (offsets[i] == ABSENT_OFFSET) {
185 		tp->Strings[i] = ABSENT_STRING;
186 	    } else if (offsets[i] == CANCELLED_OFFSET) {
187 		tp->Strings[i] = CANCELLED_STRING;
188 	    } else {
189 		tp->Strings[i] = tp->str_table + offsets[i];
190 	    }
191 	}
192     }
193 
194 #if NCURSES_XNAMES
195     if (!copy_strings) {
196 	if ((n = (unsigned) NUM_EXT_NAMES(tp)) != 0) {
197 	    if (n < SIZEOF(offsets)) {
198 		size_t length = 0;
199 		size_t offset;
200 		for (i = 0; i < n; i++) {
201 		    length += strlen(tp->ext_Names[i]) + 1;
202 		    offsets[i] = (int) (tp->ext_Names[i] - stringbuf);
203 		}
204 		TYPE_MALLOC(char, length, tp->ext_str_table);
205 		for (i = 0, offset = 0; i < n; i++) {
206 		    tp->ext_Names[i] = tp->ext_str_table + offset;
207 		    _nc_STRCPY(tp->ext_Names[i],
208 			       stringbuf + offsets[i],
209 			       length - offset);
210 		    offset += strlen(tp->ext_Names[i]) + 1;
211 		}
212 	    }
213 	}
214     }
215 #endif
216 
217     for (i = 0; i < nuses; i++) {
218 	if (useoffsets[i] == ABSENT_OFFSET)
219 	    ep->uses[i].name = 0;
220 	else
221 	    ep->uses[i].name = (tp->str_table + useoffsets[i]);
222     }
223 }
224 
225 NCURSES_EXPORT(void)
226 _nc_merge_entry(ENTRY * const target, ENTRY * const source)
227 /* merge capabilities from `from' entry into `to' entry */
228 {
229     TERMTYPE2 *to = &(target->tterm);
230     TERMTYPE2 *from = &(source->tterm);
231 #if NCURSES_XNAMES
232     TERMTYPE2 copy;
233 #endif
234     unsigned i;
235 
236     if (source == 0 || from == 0 || target == 0 || to == 0)
237 	return;
238 
239 #if NCURSES_XNAMES
240     _nc_copy_termtype2(&copy, from);
241     from = &copy;
242     _nc_align_termtype(to, from);
243 #endif
244     for_each_boolean(i, from) {
245 	if (to->Booleans[i] != (char) CANCELLED_BOOLEAN) {
246 	    int mergebool = from->Booleans[i];
247 
248 	    if (mergebool == CANCELLED_BOOLEAN)
249 		to->Booleans[i] = FALSE;
250 	    else if (mergebool == TRUE)
251 		to->Booleans[i] = (NCURSES_SBOOL) mergebool;
252 	}
253     }
254 
255     for_each_number(i, from) {
256 	if (to->Numbers[i] != CANCELLED_NUMERIC) {
257 	    int mergenum = from->Numbers[i];
258 
259 	    if (mergenum == CANCELLED_NUMERIC)
260 		to->Numbers[i] = ABSENT_NUMERIC;
261 	    else if (mergenum != ABSENT_NUMERIC)
262 		to->Numbers[i] = (NCURSES_INT2) mergenum;
263 	}
264     }
265 
266     /*
267      * Note: the copies of strings this makes don't have their own
268      * storage.  This is OK right now, but will be a problem if we
269      * we ever want to deallocate entries.
270      */
271     for_each_string(i, from) {
272 	if (to->Strings[i] != CANCELLED_STRING) {
273 	    char *mergestring = from->Strings[i];
274 
275 	    if (mergestring == CANCELLED_STRING)
276 		to->Strings[i] = ABSENT_STRING;
277 	    else if (mergestring != ABSENT_STRING)
278 		to->Strings[i] = mergestring;
279 	}
280     }
281 #if NCURSES_XNAMES
282     /* Discard the data allocated in _nc_copy_termtype2, but do not use
283      * _nc_free_termtype2 because that frees the string-table (which is
284      * not allocated by _nc_copy_termtype2).
285      */
286     free(copy.Booleans);
287     free(copy.Numbers);
288     free(copy.Strings);
289     free(copy.ext_Names);
290 #endif
291 }
292 
293 #if NO_LEAKS
294 NCURSES_EXPORT(void)
295 _nc_alloc_entry_leaks(void)
296 {
297     if (stringbuf != 0) {
298 	FreeAndNull(stringbuf);
299     }
300     next_free = 0;
301 }
302 #endif
303