fmtcheck.c revision 81586 
1/*	$NetBSD: fmtcheck.c,v 1.2 2000/11/01 01:17:20 briggs Exp $	*/
2
3/*-
4 * Copyright (c) 2000 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code was contributed to The NetBSD Foundation by Allen Briggs.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *        This product includes software developed by the NetBSD
20 *        Foundation, Inc. and its contributors.
21 * 4. Neither the name of The NetBSD Foundation nor the names of its
22 *    contributors may be used to endorse or promote products derived
23 *    from this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
26 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38#include <sys/cdefs.h>
39#ifndef lint
40static const char rcsid[] =
41  "$FreeBSD: head/lib/libc/gen/fmtcheck.c 81586 2001-08-13 14:06:34Z ru $";
42#endif /* not lint */
43
44#include "namespace.h"
45
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
54enum __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};
72typedef 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
79static EFT
80get_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
166static EFT
167get_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
185static EFT
186get_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 *
232fmtcheck(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