xref: /netbsd-src/lib/libform/type_enum.c (revision 0cf983201b7d99809917d68383abdc4de8c5dbeb)
1 /*	$NetBSD: type_enum.c,v 1.13 2021/04/13 13:13:04 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1998-1999 Brett Lymn
5  *                         (blymn@baea.com.au, brett_lymn@yahoo.com.au)
6  * All rights reserved.
7  *
8  * This code has been donated to The NetBSD Foundation by the Author.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  *
29  *
30  */
31 
32 #include <sys/cdefs.h>
33 __RCSID("$NetBSD: type_enum.c,v 1.13 2021/04/13 13:13:04 christos Exp $");
34 
35 #include <ctype.h>
36 #include <stdlib.h>
37 #include <strings.h>
38 #include "form.h"
39 #include "internals.h"
40 
41 /*
42  * Prototypes.
43  */
44 static int
45 trim_blanks(char *field);
46 
47 /*
48  * The enum type handling.
49  */
50 
51 typedef struct
52 {
53 	char **choices;
54 	unsigned num_choices;
55 	bool ignore_case;
56 	bool exact;
57 } enum_args;
58 
59 /*
60  * Find the first non-blank character at the end of a field, return the
61  * index of that character.
62  */
63 static int
trim_blanks(char * field)64 trim_blanks(char *field)
65 {
66 	int i;
67 
68 	i = (int) strlen(field);
69 	if (i > 0)
70 		i--;
71 	else
72 		return 0;
73 
74 	while ((i > 0) && isblank((unsigned char)field[i]))
75 		i--;
76 
77 	return i;
78 }
79 
80 /*
81  * Create the enum arguments structure from the given args.  Return NULL
82  * if the call fails, otherwise return a pointer to the structure allocated.
83  */
84 static char *
create_enum_args(va_list * args)85 create_enum_args(va_list *args)
86 {
87 	enum_args *new;
88 	char **choices;
89 
90 	new = malloc(sizeof(*new));
91 	if (new == NULL)
92 		return NULL;
93 
94 	new->choices = va_arg(*args, char **);
95 	new->ignore_case = (va_arg(*args, int)) ? TRUE : FALSE;
96 	new->exact = (va_arg(*args, int)) ? TRUE : FALSE;
97 
98 	_formi_dbg_printf("%s: ignore_case %d, no_blanks %d\n", __func__,
99 	    new->ignore_case, new->exact);
100 
101 	  /* count the choices we have */
102 	choices = new->choices;
103 	new->num_choices = 0;
104 	while (*choices != NULL) {
105 		_formi_dbg_printf("%s: choice[%u] = \'%s\'\n", __func__,
106 		    new->num_choices, new->choices[new->num_choices]);
107 		new->num_choices++;
108 		choices++;
109 	}
110 	_formi_dbg_printf("%s: have %u choices\n", __func__,
111 	    new->num_choices);
112 
113 	return (void *) new;
114 }
115 
116 /*
117  * Copy the enum argument structure.
118  */
119 static char *
copy_enum_args(char * args)120 copy_enum_args(char *args)
121 {
122 	enum_args *new;
123 
124 	new = malloc(sizeof(*new));
125 
126 	if (new != NULL)
127 		memcpy(new, args, sizeof(*new));
128 
129 	return (void *) new;
130 }
131 
132 /*
133  * Free the allocated storage associated with the type arguments.
134  */
135 static void
free_enum_args(char * args)136 free_enum_args(char *args)
137 {
138 	if (args != NULL)
139 		free(args);
140 }
141 
142 /*
143  * Attempt to match the string in this to the choices given.  Returns
144  * TRUE if match found otherwise FALSE.
145  *
146  */
147 static bool
match_enum(char ** choices,unsigned num_choices,bool ignore_case,bool exact,char * this,unsigned * match_num)148 match_enum(char **choices, unsigned num_choices, bool ignore_case,
149 	   bool exact, char *this, unsigned *match_num)
150 {
151 	unsigned i, start, end, enum_start, blen, elen, enum_end;
152 	bool cur_match;
153 
154 	start = _formi_skip_blanks(this, 0);
155 	end = trim_blanks(this);
156 
157 	if (end >= start)
158 		blen = (unsigned) (strlen(&this[start])
159 				   - strlen(&this[end]) + 1);
160 	else
161 		blen = 0;
162 
163 	_formi_dbg_printf("%s: start %u, blen %u\n", __func__, start, blen);
164 	for (i = 0; i < num_choices; i++) {
165 		enum_start = _formi_skip_blanks(choices[i], 0);
166 		enum_end = trim_blanks(choices[i]);
167 
168 		if (enum_end >= enum_start)
169 			elen = (unsigned) (strlen(&choices[i][enum_start])
170 				- strlen(&choices[i][enum_end]) + 1);
171 		else
172 			elen = 0;
173 
174 		_formi_dbg_printf("%s: checking choice \'%s\'\n", __func__,
175 			choices[i]);
176 		_formi_dbg_printf("%s: enum_start %u, elen %u\n", __func__,
177 			enum_start, elen);
178 
179 		  /* don't bother if we are after an exact match
180 		   * and the test length is not equal to the enum
181 		   * in question - it will never match.
182 		   */
183 		if ((exact == TRUE) && (blen != elen))
184 			continue;
185 
186 		  /*
187 		   * If the test length is longer than the enum
188 		   * length then there is no chance of a match
189 		   * so we skip.
190 		   */
191 		if ((exact != TRUE) && (blen > elen))
192 			continue;
193 
194 		if (ignore_case)
195 			cur_match = (strncasecmp(&choices[i][enum_start],
196 						 &this[start],
197 						 (size_t)blen) == 0) ?
198 				TRUE : FALSE;
199 		else
200 			cur_match = (strncmp(&choices[i][enum_start],
201 					     &this[start],
202 					     (size_t) blen) == 0) ?
203 				TRUE : FALSE;
204 
205 		_formi_dbg_printf("%s: curmatch is %s\n", __func__,
206 			(cur_match == TRUE)? "TRUE" : "FALSE");
207 
208 		if (cur_match == TRUE) {
209 			*match_num = i;
210 			return TRUE;
211 		}
212 
213 	}
214 
215 	_formi_dbg_printf("%s: no match found\n", __func__);
216 	return FALSE;
217 }
218 
219 /*
220  * Check the contents of the field buffer match one of the enum strings only.
221  */
222 static int
enum_check_field(FIELD * field,char * args)223 enum_check_field(FIELD *field, char *args)
224 {
225 	enum_args *ta;
226 	unsigned match_num;
227 
228 	if (args == NULL)
229 		return FALSE;
230 
231 	ta = (enum_args *) (void *) field->args;
232 
233 	if (match_enum(ta->choices, ta->num_choices, ta->ignore_case,
234 		       ta->exact, args, &match_num) == TRUE) {
235 		_formi_dbg_printf("%s: We matched, match_num %u\n", __func__,
236 		    match_num);
237 		_formi_dbg_printf("%s: buffer is \'%s\'\n", __func__,
238 		    ta->choices[match_num]);
239 		set_field_buffer(field, 0, ta->choices[match_num]);
240 		return TRUE;
241 	}
242 
243 	return FALSE;
244 }
245 
246 /*
247  * Get the next enum in the list of choices.
248  */
249 static int
next_enum(FIELD * field,char * args)250 next_enum(FIELD *field, char *args)
251 {
252 	enum_args *ta;
253 	unsigned cur_choice;
254 
255 	if (args == NULL)
256 		return FALSE;
257 
258 	ta = (enum_args *) (void *) field->args;
259 
260 	_formi_dbg_printf("%s: attempt to match \'%s\'\n", __func__, args);
261 
262 	if (match_enum(ta->choices, ta->num_choices, ta->ignore_case,
263 		       ta->exact, args, &cur_choice) == FALSE) {
264 		_formi_dbg_printf("%s: match failed\n", __func__);
265 		return FALSE;
266 	}
267 
268 	_formi_dbg_printf("%s: cur_choice is %u\n", __func__, cur_choice);
269 
270 	cur_choice++;
271 
272 	if (cur_choice >= ta->num_choices)
273 		cur_choice = 0;
274 
275 	_formi_dbg_printf("%s: cur_choice is %u on exit\n", __func__,
276 	    cur_choice);
277 
278 	set_field_buffer(field, 0, ta->choices[cur_choice]);
279 	return TRUE;
280 }
281 
282 /*
283  * Get the previous enum in the list of choices.
284  */
285 static int
prev_enum(FIELD * field,char * args)286 prev_enum(FIELD *field, char *args)
287 {
288 	enum_args *ta;
289 	unsigned cur_choice;
290 
291 	if (args == NULL)
292 		return FALSE;
293 
294 	ta = (enum_args *) (void *) field->args;
295 
296 	_formi_dbg_printf("%s: attempt to match \'%s\'\n", __func__, args);
297 
298 	if (match_enum(ta->choices, ta->num_choices, ta->ignore_case,
299 		       ta->exact, args, &cur_choice) == FALSE) {
300 		_formi_dbg_printf("%s: match failed\n", __func__);
301 		return FALSE;
302 	}
303 
304 	_formi_dbg_printf("%s: cur_choice is %u\n", __func__, cur_choice);
305 	if (cur_choice == 0)
306 		cur_choice = ta->num_choices - 1;
307 	else
308 		cur_choice--;
309 
310 	_formi_dbg_printf("%s: cur_choice is %u on exit\n",
311 	    __func__, cur_choice);
312 
313 	set_field_buffer(field, 0, ta->choices[cur_choice]);
314 	return TRUE;
315 }
316 
317 
318 static FIELDTYPE builtin_enum = {
319 	_TYPE_HAS_ARGS | _TYPE_IS_BUILTIN,  /* flags */
320 	0,                                  /* refcount */
321 	NULL,                               /* link */
322 	create_enum_args,                  /* make_args */
323 	copy_enum_args,                    /* copy_args */
324 	free_enum_args,                    /* free_args */
325 	enum_check_field,                  /* field_check */
326 	NULL,                              /* char_check */
327 	next_enum,                         /* next_choice */
328 	prev_enum                          /* prev_choice */
329 };
330 
331 FIELDTYPE *TYPE_ENUM = &builtin_enum;
332 
333 
334