lib/libc/gen/fmtcheck.c

   1 /*      $NetBSD: fmtcheck.c,v 1.8 2008/04/28 20:22:59 martin 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  *
  18  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  20  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  21  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  22  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  28  * POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include <sys/cdefs.h>
  32 #if defined(LIBC_SCCS) && !defined(lint)
  33 __RCSID("$NetBSD: fmtcheck.c,v 1.8 2008/04/28 20:22:59 martin Exp $");
  34 #endif
  35
  36 #include "namespace.h"
  37
  38 #include <stdio.h>
  39 #include <string.h>
  40 #include <ctype.h>
  41
  42 #ifdef __weak_alias
  43 __weak_alias(fmtcheck,__fmtcheck)
  44 #endif
  45
  46 enum __e_fmtcheck_types {
  47         FMTCHECK_START,
  48         FMTCHECK_SHORT,
  49         FMTCHECK_INT,
  50         FMTCHECK_LONG,
  51         FMTCHECK_QUAD,
  52         FMTCHECK_SHORTPOINTER,
  53         FMTCHECK_INTPOINTER,
  54         FMTCHECK_LONGPOINTER,
  55         FMTCHECK_QUADPOINTER,
  56         FMTCHECK_DOUBLE,
  57         FMTCHECK_LONGDOUBLE,
  58         FMTCHECK_STRING,
  59         FMTCHECK_WIDTH,
  60         FMTCHECK_PRECISION,
  61         FMTCHECK_DONE,
  62         FMTCHECK_UNKNOWN
  63 };
  64 typedef enum __e_fmtcheck_types EFT;
  65
  66 #define RETURN(pf,f,r) do { \
  67                         *(pf) = (f); \
  68                         return r; \
  69                        } /*NOTREACHED*/ /*CONSTCOND*/ while (0)
  70
  71 static EFT
  72 get_next_format_from_precision(const char **pf)
  73 {
  74         int             sh, lg, quad, longdouble;
  75         const char      *f;
  76
  77         sh = lg = quad = longdouble = 0;
  78
  79         f = *pf;
  80         switch (*f) {
  81         case 'h':
  82                 f++;
  83                 sh = 1;
  84                 break;
  85         case 'l':
  86                 f++;
  87                 if (!*f) RETURN(pf,f,FMTCHECK_UNKNOWN);
  88                 if (*f == 'l') {
  89                         f++;
  90                         quad = 1;
  91                 } else {
  92                         lg = 1;
  93                 }
  94                 break;
  95         case 'q':
  96                 f++;
  97                 quad = 1;
  98                 break;
  99         case 'L':
 100                 f++;
 101                 longdouble = 1;
 102                 break;
 103         default:
 104                 break;
 105         }
 106         if (!*f) RETURN(pf,f,FMTCHECK_UNKNOWN);
 107         if (strchr("diouxX", *f)) {
 108                 if (longdouble)
 109                         RETURN(pf,f,FMTCHECK_UNKNOWN);
 110                 if (lg)
 111                         RETURN(pf,f,FMTCHECK_LONG);
 112                 if (quad)
 113                         RETURN(pf,f,FMTCHECK_QUAD);
 114                 RETURN(pf,f,FMTCHECK_INT);
 115         }
 116         if (*f == 'n') {
 117                 if (longdouble)
 118                         RETURN(pf,f,FMTCHECK_UNKNOWN);
 119                 if (sh)
 120                         RETURN(pf,f,FMTCHECK_SHORTPOINTER);
 121                 if (lg)
 122                         RETURN(pf,f,FMTCHECK_LONGPOINTER);
 123                 if (quad)
 124                         RETURN(pf,f,FMTCHECK_QUADPOINTER);
 125                 RETURN(pf,f,FMTCHECK_INTPOINTER);
 126         }
 127         if (strchr("DOU", *f)) {
 128                 if (sh + lg + quad + longdouble)
 129                         RETURN(pf,f,FMTCHECK_UNKNOWN);
 130                 RETURN(pf,f,FMTCHECK_LONG);
 131         }
 132         if (strchr("eEfg", *f)) {
 133                 if (longdouble)
 134                         RETURN(pf,f,FMTCHECK_LONGDOUBLE);
 135                 if (sh + lg + quad)
 136                         RETURN(pf,f,FMTCHECK_UNKNOWN);
 137                 RETURN(pf,f,FMTCHECK_DOUBLE);
 138         }
 139         if (*f == 'c') {
 140                 if (sh + lg + quad + longdouble)
 141                         RETURN(pf,f,FMTCHECK_UNKNOWN);
 142                 RETURN(pf,f,FMTCHECK_INT);
 143         }
 144         if (*f == 's') {
 145                 if (sh + lg + quad + longdouble)
 146                         RETURN(pf,f,FMTCHECK_UNKNOWN);
 147                 RETURN(pf,f,FMTCHECK_STRING);
 148         }
 149         if (*f == 'p') {
 150                 if (sh + lg + quad + longdouble)
 151                         RETURN(pf,f,FMTCHECK_UNKNOWN);
 152                 RETURN(pf,f,FMTCHECK_LONG);
 153         }
 154         RETURN(pf,f,FMTCHECK_UNKNOWN);
 155         /*NOTREACHED*/
 156 }
 157
 158 static EFT
 159 get_next_format_from_width(const char **pf)
 160 {
 161         const char      *f;
 162
 163         f = *pf;
 164         if (*f == '.') {
 165                 f++;
 166                 if (*f == '*') {
 167                         RETURN(pf,f,FMTCHECK_PRECISION);
 168                 }
 169                 /* eat any precision (empty is allowed) */
 170                 while (isdigit((unsigned char)*f)) f++;
 171                 if (!*f) RETURN(pf,f,FMTCHECK_UNKNOWN);
 172         }
 173         RETURN(pf,f,get_next_format_from_precision(pf));
 174         /*NOTREACHED*/
 175 }
 176
 177 static EFT
 178 get_next_format(const char **pf, EFT eft)
 179 {
 180         int             infmt;
 181         const char      *f;
 182
 183         if (eft == FMTCHECK_WIDTH) {
 184                 (*pf)++;
 185                 return get_next_format_from_width(pf);
 186         } else if (eft == FMTCHECK_PRECISION) {
 187                 (*pf)++;
 188                 return get_next_format_from_precision(pf);
 189         }
 190
 191         f = *pf;
 192         infmt = 0;
 193         while (!infmt) {
 194                 f = strchr(f, '%');
 195                 if (f == NULL)
 196                         RETURN(pf,f,FMTCHECK_DONE);
 197                 f++;
 198                 if (!*f)
 199                         RETURN(pf,f,FMTCHECK_UNKNOWN);
 200                 if (*f != '%')
 201                         infmt = 1;
 202                 else
 203                         f++;
 204         }
 205
 206         /* Eat any of the flags */
 207         while (*f && (strchr("#0- +", *f)))
 208                 f++;
 209
 210         if (*f == '*') {
 211                 RETURN(pf,f,FMTCHECK_WIDTH);
 212         }
 213         /* eat any width */
 214         while (isdigit((unsigned char)*f)) f++;
 215         if (!*f) {
 216                 RETURN(pf,f,FMTCHECK_UNKNOWN);
 217         }
 218
 219         RETURN(pf,f,get_next_format_from_width(pf));
 220         /*NOTREACHED*/
 221 }
 222
 223 const char *
 224 fmtcheck(const char *f1, const char *f2)
 225 {
 226         const char      *f1p, *f2p;
 227         EFT             f1t, f2t;
 228
 229         if (!f1) return f2;
 230
 231         f1p = f1;
 232         f1t = FMTCHECK_START;
 233         f2p = f2;
 234         f2t = FMTCHECK_START;
 235         while ((f1t = get_next_format(&f1p, f1t)) != FMTCHECK_DONE) {
 236                 if (f1t == FMTCHECK_UNKNOWN)
 237                         return f2;
 238                 f2t = get_next_format(&f2p, f2t);
 239                 if (f1t != f2t)
 240                         return f2;
 241         }
 242         return f1;
 243 }