release/src/router/libncurses/ncurses/base/vsscanf.c

   1 /****************************************************************************
   2  * Copyright (c) 1998-2003,2004 Free Software Foundation, Inc.              *
   3  *                                                                          *
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   5  * copy of this software and associated documentation files (the            *
   6  * "Software"), to deal in the Software without restriction, including      *
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   9  * copies of the Software, and to permit persons to whom the Software is    *
  10  * furnished to do so, subject to the following conditions:                 *
  11  *                                                                          *
  12  * The above copyright notice and this permission notice shall be included  *
  13  * in all copies or substantial portions of the Software.                   *
  14  *                                                                          *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
  16  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
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  18  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
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  28
  29 /****************************************************************************
  30  *  State-machine fallback written by Thomas E. Dickey 2002                 *
  31  ****************************************************************************/
  32
  33 /*
  34  * This function is needed to support vwscanw
  35  */
  36
  37 #include <curses.priv.h>
  38
  39 #if !HAVE_VSSCANF
  40
  41 MODULE_ID("$Id: vsscanf.c,v 1.18 2004/04/03 20:27:02 tom Exp $")
  42
  43 #if !(HAVE_VFSCANF || HAVE__DOSCAN)
  44
  45 #include <ctype.h>
  46
  47 #define L_SQUARE '['
  48 #define R_SQUARE ']'
  49
  50 typedef enum {
  51     cUnknown
  52     ,cError                     /* anything that isn't ANSI */
  53     ,cAssigned
  54     ,cChar
  55     ,cInt
  56     ,cFloat
  57     ,cDouble
  58     ,cPointer
  59     ,cLong
  60     ,cShort
  61     ,cRange
  62     ,cString
  63 } ChunkType;
  64
  65 typedef enum {
  66     oUnknown
  67     ,oShort
  68     ,oLong
  69 } OtherType;
  70
  71 typedef enum {
  72     sUnknown
  73     ,sPercent                   /* last was '%' beginning a format */
  74     ,sNormal                    /* ...somewhere in the middle */
  75     ,sLeft                      /* last was left square bracket beginning a range */
  76     ,sRange                     /* ...somewhere in the middle */
  77     ,sFinal                     /* last finished a format */
  78 } ScanState;
  79
  80 static ChunkType
  81 final_ch(int ch, OtherType other)
  82 {
  83     ChunkType result = cUnknown;
  84
  85     switch (ch) {
  86     case 'c':
  87         if (other == oUnknown)
  88             result = cChar;
  89         else
  90             result = cError;
  91         break;
  92     case 'd':
  93     case 'i':
  94     case 'X':
  95     case 'x':
  96         switch (other) {
  97         case oUnknown:
  98             result = cInt;
  99             break;
 100         case oShort:
 101             result = cShort;
 102             break;
 103         case oLong:
 104             result = cLong;
 105             break;
 106         }
 107         break;
 108     case 'E':
 109     case 'e':
 110     case 'f':
 111     case 'g':
 112         switch (other) {
 113         case oUnknown:
 114             result = cFloat;
 115             break;
 116         case oShort:
 117             result = cError;
 118             break;
 119         case oLong:
 120             result = cDouble;
 121             break;
 122         }
 123         break;
 124     case 'n':
 125         if (other == oUnknown)
 126             result = cAssigned;
 127         else
 128             result = cError;
 129         break;
 130     case 'p':
 131         if (other == oUnknown)
 132             result = cPointer;
 133         else
 134             result = cError;
 135         break;
 136     case 's':
 137         if (other == oUnknown)
 138             result = cString;
 139         else
 140             result = cError;
 141         break;
 142     }
 143     return result;
 144 }
 145
 146 static OtherType
 147 other_ch(int ch)
 148 {
 149     OtherType result = oUnknown;
 150     switch (ch) {
 151     case 'h':
 152         result = oShort;
 153         break;
 154     case 'l':
 155         result = oLong;
 156         break;
 157     }
 158     return result;
 159 }
 160 #endif
 161
 162 /*VARARGS2*/
 163 NCURSES_EXPORT(int)
 164 vsscanf(const char *str, const char *format, va_list ap)
 165 {
 166 #if HAVE_VFSCANF || HAVE__DOSCAN
 167     /*
 168      * This code should work on anything descended from AT&T SVr1.
 169      */
 170     FILE strbuf;
 171
 172     strbuf._flag = _IOREAD;
 173     strbuf._ptr = strbuf._base = (unsigned char *) str;
 174     strbuf._cnt = strlen(str);
 175     strbuf._file = _NFILE;
 176
 177 #if HAVE_VFSCANF
 178     return (vfscanf(&strbuf, format, ap));
 179 #else
 180     return (_doscan(&strbuf, format, ap));
 181 #endif
 182 #else
 183     static int can_convert = -1;
 184
 185     int assigned = 0;
 186     int consumed = 0;
 187
 188     T((T_CALLED("vsscanf(%s,%s,...)"),
 189        _nc_visbuf2(1, str),
 190        _nc_visbuf2(2, format)));
 191
 192     /*
 193      * This relies on having a working "%n" format conversion.  Check if it
 194      * works.  Only very old C libraries do not support it.
 195      *
 196      * FIXME: move this check into the configure script.
 197      */
 198     if (can_convert < 0) {
 199         int check1;
 200         int check2;
 201         if (sscanf("123", "%d%n", &check1, &check2) > 0
 202             && check1 == 123
 203             && check2 == 3) {
 204             can_convert = 1;
 205         } else {
 206             can_convert = 0;
 207         }
 208     }
 209
 210     if (can_convert) {
 211         size_t len_fmt = strlen(format) + 32;
 212         char *my_fmt = malloc(len_fmt);
 213         ChunkType chunk, ctest;
 214         OtherType other, otest;
 215         ScanState state;
 216         unsigned n;
 217         int eaten;
 218         void *pointer;
 219
 220         if (my_fmt != 0) {
 221             /*
 222              * Split the original format into chunks, adding a "%n" to the end
 223              * of each (except of course if it used %n), and use that
 224              * information to decide where to start scanning the next chunk.
 225              *
 226              * FIXME:  does %n count bytes or characters?  If the latter, this
 227              * will require further work for multibyte strings.
 228              */
 229             while (*format != '\0') {
 230                 /* find a chunk */
 231                 state = sUnknown;
 232                 chunk = cUnknown;
 233                 other = oUnknown;
 234                 pointer = 0;
 235                 for (n = 0; format[n] != 0 && state != sFinal; ++n) {
 236                     my_fmt[n] = format[n];
 237                     switch (state) {
 238                     case sUnknown:
 239                         if (format[n] == '%')
 240                             state = sPercent;
 241                         break;
 242                     case sPercent:
 243                         if (format[n] == '%') {
 244                             state = sUnknown;
 245                         } else if (format[n] == L_SQUARE) {
 246                             state = sLeft;
 247                         } else {
 248                             state = sNormal;
 249                             --n;
 250                         }
 251                         break;
 252                     case sLeft:
 253                         state = sRange;
 254                         if (format[n] == '^') {
 255                             ++n;
 256                             my_fmt[n] = format[n];
 257                         }
 258                         break;
 259                     case sRange:
 260                         if (format[n] == R_SQUARE) {
 261                             state = sFinal;
 262                             chunk = cRange;
 263                         }
 264                         break;
 265                     case sNormal:
 266                         if (format[n] == '*') {
 267                             state = sUnknown;
 268                         } else {
 269                             if ((ctest = final_ch(format[n], other)) != cUnknown) {
 270                                 state = sFinal;
 271                                 chunk = ctest;
 272                             } else if ((otest = other_ch(format[n])) != oUnknown) {
 273                                 other = otest;
 274                             } else if (isalpha(UChar(format[n]))) {
 275                                 state = sFinal;
 276                                 chunk = cError;
 277                             }
 278                         }
 279                         break;
 280                     case sFinal:
 281                         break;
 282                     }
 283                 }
 284                 my_fmt[n] = '\0';
 285                 format += n;
 286
 287                 if (chunk == cUnknown
 288                     || chunk == cError) {
 289                     if (assigned == 0)
 290                         assigned = EOF;
 291                     break;
 292                 }
 293
 294                 /* add %n, if the format was not that */
 295                 if (chunk != cAssigned) {
 296                     strcat(my_fmt, "%n");
 297                 }
 298
 299                 switch (chunk) {
 300                 case cAssigned:
 301                     strcat(my_fmt, "%n");
 302                     pointer = &eaten;
 303                     break;
 304                 case cInt:
 305                     pointer = va_arg(ap, int *);
 306                     break;
 307                 case cShort:
 308                     pointer = va_arg(ap, short *);
 309                     break;
 310                 case cFloat:
 311                     pointer = va_arg(ap, float *);
 312                     break;
 313                 case cDouble:
 314                     pointer = va_arg(ap, double *);
 315                     break;
 316                 case cLong:
 317                     pointer = va_arg(ap, long *);
 318                     break;
 319                 case cPointer:
 320                     pointer = va_arg(ap, void *);
 321                     break;
 322                 case cChar:
 323                 case cRange:
 324                 case cString:
 325                     pointer = va_arg(ap, char *);
 326                     break;
 327                 case cError:
 328                 case cUnknown:
 329                     break;
 330                 }
 331                 /* do the conversion */
 332                 T(("...converting chunk #%d type %d(%s,%s)",
 333                    assigned + 1, chunk,
 334                    _nc_visbuf2(1, str + consumed),
 335                    _nc_visbuf2(2, my_fmt)));
 336                 if (sscanf(str + consumed, my_fmt, pointer, &eaten) > 0)
 337                     consumed += eaten;
 338                 else
 339                     break;
 340                 ++assigned;
 341             }
 342             free(my_fmt);
 343         }
 344     }
 345     returnCode(assigned);
 346 #endif
 347 }
 348 #else
 349 extern
 350 NCURSES_EXPORT(void)
 351 _nc_vsscanf(void);              /* quiet's gcc warning */
 352 NCURSES_EXPORT(void)
 353 _nc_vsscanf(void)
 354 {
 355 }                               /* nonempty for strict ANSI compilers */
 356 #endif /* !HAVE_VSSCANF */