xref: /netbsd/lib/libform/type_numeric.c (revision bf9ec67e)
1 /*	$NetBSD: type_numeric.c,v 1.4 2001/06/13 10:45:59 wiz 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 <stdlib.h>
33 #include <string.h>
34 #include <ctype.h>
35 #include "form.h"
36 #include "internals.h"
37 
38 /*
39  * The numeric type handling.
40  */
41 
42 typedef struct
43 {
44 	unsigned precision;
45 	double min;
46 	double max;
47 } numeric_args;
48 
49 /*
50  * Create the numeric arguments structure from the given args.  Return NULL
51  * if the call fails, otherwise return a pointer to the structure allocated.
52  */
53 static char *
54 create_numeric_args(va_list *args)
55 {
56 	numeric_args *new;
57 
58 	new = (numeric_args *) malloc(sizeof(numeric_args));
59 
60 	if (new != NULL) {
61 		new->precision = va_arg(*args, unsigned);
62 		new->min = va_arg(*args, double);
63 		new->max = va_arg(*args, double);
64 	}
65 
66 	return (void *) new;
67 }
68 
69 /*
70  * Copy the the numeric argument structure.
71  */
72 static char *
73 copy_numeric_args(char *args)
74 {
75 	numeric_args *new;
76 
77 	new = (numeric_args *) malloc(sizeof(numeric_args));
78 
79 	if (new != NULL)
80 		bcopy(args, new, sizeof(numeric_args));
81 
82 	return (void *) new;
83 }
84 
85 /*
86  * Free the allocated storage associated with the type arguments.
87  */
88 static void
89 free_numeric_args(char *args)
90 {
91 	if (args != NULL)
92 		free(args);
93 }
94 
95 /*
96  * Check the contents of the field buffer are numeric only.  A valid
97  * number is of the form nnnn[.mmmmm][Ee[+-]ddd]
98  */
99 static int
100 numeric_check_field(FIELD *field, char *args)
101 {
102 	int cur;
103 	double number, max, min;
104 	int precision;
105 	char *buf, *new_buf;
106 
107 	if (args == NULL)
108 		return FALSE;
109 
110 	precision = ((numeric_args *) (void *) field->args)->precision;
111 	min = ((numeric_args *) (void *) field->args)->min;
112 	max = ((numeric_args *) (void *) field->args)->max;
113 
114 	buf = args;
115 	cur = 0;
116 
117 	  /* skip leading white space */
118 	while ((buf[cur] != '\0')
119 	       && ((buf[cur] == ' ') || (buf[cur] == '\t')))
120 		cur++;
121 
122 	  /* no good if we have hit the end */
123 	if (buf[cur] == '\0')
124 		return FALSE;
125 
126 	  /* find the end of the digits but allow a leading + or - sign, and
127 	   * a decimal point.
128 	   */
129 	if ((buf[cur] == '-') || (buf[cur] == '+'))
130 		cur++;
131 
132 	while((buf[cur] != '\0') && isdigit(buf[cur]))
133 		cur++;
134 
135 	  /* if not at end of string then check for decimal... */
136 	if ((buf[cur] != '\0') && (buf[cur] == '.')) {
137 		cur++;
138 		  /* check for more digits now.... */
139 		while((buf[cur] != '\0') && isdigit(buf[cur]))
140 			cur++;
141 	}
142 
143 	  /* check for an exponent */
144 	if ((buf[cur] != '\0') &&
145 	    ((buf[cur] == 'E') || (buf[cur] == 'e'))) {
146 		cur++;
147 		if (buf[cur] == '\0')
148 			return FALSE;
149 
150 		  /* allow a + or a - for exponent */
151 		if ((buf[cur] == '+') || (buf[cur] == '-'))
152 			cur++;
153 
154 		if (buf[cur] == '\0')
155 			return FALSE;
156 
157 		  /* we expect a digit now */
158 		if (!isdigit(buf[cur]))
159 			return FALSE;
160 
161 		  /* skip digits for the final time */
162 		while((buf[cur] != '\0') && isdigit(buf[cur]))
163 			cur++;
164 	}
165 
166 	  /* check there is only trailing whitespace */
167 	while ((buf[cur] != '\0')
168 	       && ((buf[cur] == ' ') || (buf[cur] == '\t')))
169 		cur++;
170 
171 	  /* no good if we are not at the end of the string */
172 	if (buf[cur] != '\0')
173 		return FALSE;
174 
175 	  /* convert and range check the number...*/
176 	number = atof(buf);
177 	if ((min < max) && ((number < min) || (number > max)))
178 		return FALSE;
179 
180 	if (asprintf(&new_buf, "%.*f", precision, number) < 0)
181 		return FALSE;
182 
183 	  /* re-set the field buffer to be the reformatted numeric */
184 	set_field_buffer(field, 0, new_buf);
185 
186 	free(new_buf);
187 
188 	  /* otherwise all was ok */
189 	return TRUE;
190 }
191 
192 /*
193  * Check the given character is numeric, return TRUE if it is.
194  */
195 static int
196 numeric_check_char(/* ARGSUSED1 */ int c, char *args)
197 {
198 	return ((isdigit(c) || (c == '-') || (c == '+')
199 		 || (c == '.') || (c == 'e') || (c == 'E')) ? TRUE : FALSE);
200 }
201 
202 static FIELDTYPE builtin_numeric = {
203 	_TYPE_HAS_ARGS | _TYPE_IS_BUILTIN,  /* flags */
204 	0,                                  /* refcount */
205 	NULL,                               /* link */
206 	create_numeric_args,                  /* make_args */
207 	copy_numeric_args,                    /* copy_args */
208 	free_numeric_args,                    /* free_args */
209 	numeric_check_field,                  /* field_check */
210 	numeric_check_char,                   /* char_check */
211 	NULL,                               /* next_choice */
212 	NULL                                /* prev_choice */
213 };
214 
215 FIELDTYPE *TYPE_NUMERIC = &builtin_numeric;
216 
217 
218