type_alpha.c revision 1.9 
1/*	$NetBSD: type_alpha.c,v 1.9 2004/10/27 19:59:24 dsl 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_alpha.c,v 1.9 2004/10/27 19:59:24 dsl Exp $");
34
35#include <stdlib.h>
36#include <string.h>
37#include <ctype.h>
38#include "form.h"
39#include "internals.h"
40
41/*
42 * The alpha type handling.
43 */
44
45typedef struct
46{
47	unsigned width;
48} alpha_args;
49
50/*
51 * Create the alpha arguments structure from the given args.  Return NULL
52 * if the call fails, otherwise return a pointer to the structure allocated.
53 */
54static char *
55create_alpha_args(va_list *args)
56{
57	alpha_args *new;
58
59	new = (alpha_args *) malloc(sizeof(alpha_args));
60
61	if (new != NULL)
62		new->width = va_arg(*args, int);
63
64	return (void *) new;
65}
66
67/*
68 * Copy the alpha argument structure.
69 */
70static char *
71copy_alpha_args(char *args)
72{
73	alpha_args *new;
74
75	new = (alpha_args *) malloc(sizeof(alpha_args));
76
77	if (new != NULL)
78		new->width = ((alpha_args *) (void *) args)->width;
79
80	return (void *) new;
81}
82
83/*
84 * Free the allocated storage associated with the type arguments.
85 */
86static void
87free_alpha_args(char *args)
88{
89	if (args != NULL)
90		free(args);
91}
92
93/*
94 * Check the contents of the field buffer are alphanumeric only.
95 */
96static int
97alpha_check_field(FIELD *field, char *args)
98{
99	int width, start, cur, end;
100	char *buf, *new;
101
102	width = ((alpha_args *) (void *) field->args)->width;
103	buf = args;
104	start = 0;
105
106	if (buf == NULL)
107		return FALSE;
108
109	  /* skip leading white space */
110	while ((buf[start] != '\0')
111	       && ((buf[start] == ' ') || (buf[start] == '\t')))
112		start++;
113
114	  /* no good if we have hit the end */
115	if (buf[start] == '\0')
116		return FALSE;
117
118	  /* find the end of the non-whitespace stuff */
119	cur = start;
120	while(isalpha(buf[cur] & 0xff))
121		cur++;
122
123	  /* no good if it exceeds the width */
124	if ((cur - start) > width)
125		return FALSE;
126
127	end = cur;
128
129	  /* check there is only trailing whitespace */
130	while ((buf[cur] != '\0')
131	       && ((buf[cur] == ' ') || (buf[cur] == '\t')))
132		cur++;
133
134	  /* no good if we are not at the end of the string */
135	if (buf[cur] != '\0')
136		return FALSE;
137
138	  /* set buffer 0 to the new string */
139	if ((new = (char *) malloc(sizeof(char) * (end - start))) == NULL)
140		return FALSE;
141
142	if ((end - start) >= 1) {
143		strncpy(new, &buf[start], (unsigned) end - start - 1);
144		new[end] = '\0';
145	} else
146		new[0] = '\0';
147
148
149	set_field_buffer(field, 0, new);
150	free(new);
151
152	  /* otherwise all was ok */
153	return TRUE;
154}
155
156/*
157 * Check the given character is alphabetic, return TRUE if it is.
158 */
159static int
160alpha_check_char(/* ARGSUSED1 */ int c, char *args)
161{
162	return (isalpha(c) ? TRUE : FALSE);
163}
164
165static FIELDTYPE builtin_alpha = {
166	_TYPE_HAS_ARGS | _TYPE_IS_BUILTIN,  /* flags */
167	0,                                  /* refcount */
168	NULL,                               /* link */
169	create_alpha_args,                  /* make_args */
170	copy_alpha_args,                    /* copy_args */
171	free_alpha_args,                    /* free_args */
172	alpha_check_field,                  /* field_check */
173	alpha_check_char,                   /* char_check */
174	NULL,                               /* next_choice */
175	NULL                                /* prev_choice */
176};
177
178FIELDTYPE *TYPE_ALPHA = &builtin_alpha;
179
180
181