xref: /dragonfly/lib/libc/gen/fmtcheck.c (revision 984263bc)
1 /*	$FreeBSD: src/lib/libc/gen/fmtcheck.c,v 1.1.2.1 2001/07/05 07:43:42 kris Exp $	*/
2 /*	$NetBSD: fmtcheck.c,v 1.2 2000/11/01 01:17:20 briggs Exp $	*/
3 
4 /*-
5  * Copyright (c) 2000 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code was contributed to The NetBSD Foundation by Allen Briggs.
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. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *        This product includes software developed by the NetBSD
21  *        Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 
39 #include <sys/cdefs.h>
40 #ifndef lint
41 static const char rcsid[] =
42   "$FreeBSD: src/lib/libc/gen/fmtcheck.c,v 1.1.2.1 2001/07/05 07:43:42 kris Exp $";
43 #endif /* not lint */
44 
45 #include <stdlib.h>
46 #include <stdio.h>
47 #include <string.h>
48 #include <ctype.h>
49 
50 #ifdef __weak_alias
51 __weak_alias(fmtcheck,__fmtcheck)
52 #endif
53 
54 enum __e_fmtcheck_types {
55 	FMTCHECK_START,
56 	FMTCHECK_SHORT,
57 	FMTCHECK_INT,
58 	FMTCHECK_LONG,
59 	FMTCHECK_QUAD,
60 	FMTCHECK_SHORTPOINTER,
61 	FMTCHECK_INTPOINTER,
62 	FMTCHECK_LONGPOINTER,
63 	FMTCHECK_QUADPOINTER,
64 	FMTCHECK_DOUBLE,
65 	FMTCHECK_LONGDOUBLE,
66 	FMTCHECK_STRING,
67 	FMTCHECK_WIDTH,
68 	FMTCHECK_PRECISION,
69 	FMTCHECK_DONE,
70 	FMTCHECK_UNKNOWN
71 };
72 typedef enum __e_fmtcheck_types EFT;
73 
74 #define RETURN(pf,f,r) do { \
75 			*(pf) = (f); \
76 			return r; \
77 		       } /*NOTREACHED*/ /*CONSTCOND*/ while (0)
78 
79 static EFT
80 get_next_format_from_precision(const char **pf)
81 {
82 	int		sh, lg, quad, longdouble;
83 	const char	*f;
84 
85 	sh = lg = quad = longdouble = 0;
86 
87 	f = *pf;
88 	switch (*f) {
89 	case 'h':
90 		f++;
91 		sh = 1;
92 		break;
93 	case 'l':
94 		f++;
95 		if (!*f) RETURN(pf,f,FMTCHECK_UNKNOWN);
96 		if (*f == 'l') {
97 			f++;
98 			quad = 1;
99 		} else {
100 			lg = 1;
101 		}
102 		break;
103 	case 'q':
104 		f++;
105 		quad = 1;
106 		break;
107 	case 'L':
108 		f++;
109 		longdouble = 1;
110 		break;
111 	default:
112 		break;
113 	}
114 	if (!*f) RETURN(pf,f,FMTCHECK_UNKNOWN);
115 	if (strchr("diouxX", *f)) {
116 		if (longdouble)
117 			RETURN(pf,f,FMTCHECK_UNKNOWN);
118 		if (lg)
119 			RETURN(pf,f,FMTCHECK_LONG);
120 		if (quad)
121 			RETURN(pf,f,FMTCHECK_QUAD);
122 		RETURN(pf,f,FMTCHECK_INT);
123 	}
124 	if (*f == 'n') {
125 		if (longdouble)
126 			RETURN(pf,f,FMTCHECK_UNKNOWN);
127 		if (sh)
128 			RETURN(pf,f,FMTCHECK_SHORTPOINTER);
129 		if (lg)
130 			RETURN(pf,f,FMTCHECK_LONGPOINTER);
131 		if (quad)
132 			RETURN(pf,f,FMTCHECK_QUADPOINTER);
133 		RETURN(pf,f,FMTCHECK_INTPOINTER);
134 	}
135 	if (strchr("DOU", *f)) {
136 		if (sh + lg + quad + longdouble)
137 			RETURN(pf,f,FMTCHECK_UNKNOWN);
138 		RETURN(pf,f,FMTCHECK_LONG);
139 	}
140 	if (strchr("eEfg", *f)) {
141 		if (longdouble)
142 			RETURN(pf,f,FMTCHECK_LONGDOUBLE);
143 		if (sh + lg + quad)
144 			RETURN(pf,f,FMTCHECK_UNKNOWN);
145 		RETURN(pf,f,FMTCHECK_DOUBLE);
146 	}
147 	if (*f == 'c') {
148 		if (sh + lg + quad + longdouble)
149 			RETURN(pf,f,FMTCHECK_UNKNOWN);
150 		RETURN(pf,f,FMTCHECK_INT);
151 	}
152 	if (*f == 's') {
153 		if (sh + lg + quad + longdouble)
154 			RETURN(pf,f,FMTCHECK_UNKNOWN);
155 		RETURN(pf,f,FMTCHECK_STRING);
156 	}
157 	if (*f == 'p') {
158 		if (sh + lg + quad + longdouble)
159 			RETURN(pf,f,FMTCHECK_UNKNOWN);
160 		RETURN(pf,f,FMTCHECK_LONG);
161 	}
162 	RETURN(pf,f,FMTCHECK_UNKNOWN);
163 	/*NOTREACHED*/
164 }
165 
166 static EFT
167 get_next_format_from_width(const char **pf)
168 {
169 	const char	*f;
170 
171 	f = *pf;
172 	if (*f == '.') {
173 		f++;
174 		if (*f == '*') {
175 			RETURN(pf,f,FMTCHECK_PRECISION);
176 		}
177 		/* eat any precision (empty is allowed) */
178 		while (isdigit(*f)) f++;
179 		if (!*f) RETURN(pf,f,FMTCHECK_UNKNOWN);
180 	}
181 	RETURN(pf,f,get_next_format_from_precision(pf));
182 	/*NOTREACHED*/
183 }
184 
185 static EFT
186 get_next_format(const char **pf, EFT eft)
187 {
188 	int		infmt;
189 	const char	*f;
190 
191 	if (eft == FMTCHECK_WIDTH) {
192 		(*pf)++;
193 		return get_next_format_from_width(pf);
194 	} else if (eft == FMTCHECK_PRECISION) {
195 		(*pf)++;
196 		return get_next_format_from_precision(pf);
197 	}
198 
199 	f = *pf;
200 	infmt = 0;
201 	while (!infmt) {
202 		f = strchr(f, '%');
203 		if (f == NULL)
204 			RETURN(pf,f,FMTCHECK_DONE);
205 		f++;
206 		if (!*f)
207 			RETURN(pf,f,FMTCHECK_UNKNOWN);
208 		if (*f != '%')
209 			infmt = 1;
210 		else
211 			f++;
212 	}
213 
214 	/* Eat any of the flags */
215 	while (*f && (strchr("#0- +", *f)))
216 		f++;
217 
218 	if (*f == '*') {
219 		RETURN(pf,f,FMTCHECK_WIDTH);
220 	}
221 	/* eat any width */
222 	while (isdigit(*f)) f++;
223 	if (!*f) {
224 		RETURN(pf,f,FMTCHECK_UNKNOWN);
225 	}
226 
227 	RETURN(pf,f,get_next_format_from_width(pf));
228 	/*NOTREACHED*/
229 }
230 
231 __const char *
232 fmtcheck(const char *f1, const char *f2)
233 {
234 	const char	*f1p, *f2p;
235 	EFT		f1t, f2t;
236 
237 	if (!f1) return f2;
238 
239 	f1p = f1;
240 	f1t = FMTCHECK_START;
241 	f2p = f2;
242 	f2t = FMTCHECK_START;
243 	while ((f1t = get_next_format(&f1p, f1t)) != FMTCHECK_DONE) {
244 		if (f1t == FMTCHECK_UNKNOWN)
245 			return f2;
246 		f2t = get_next_format(&f2p, f2t);
247 		if (f1t != f2t)
248 			return f2;
249 	}
250 	return f1;
251 }
252