stdio-common/printf-parsemb.c

   1 /* Helper functions for parsing printf format strings.
   2    Copyright (C) 1995-2000,2002-2004,2006,2009 Free Software Foundation, Inc.
   3    This file is part of th GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <ctype.h>
  21 #include <limits.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <sys/param.h>
  25 #include <wchar.h>
  26 #include <wctype.h>
  27
  28 #ifndef COMPILE_WPRINTF
  29 # define CHAR_T         char
  30 # define UCHAR_T        unsigned char
  31 # define INT_T          int
  32 # define L_(Str)        Str
  33 # define ISDIGIT(Ch)    isdigit (Ch)
  34 # define HANDLE_REGISTERED_MODIFIER __handle_registered_modifier_mb
  35 #else
  36 # define CHAR_T         wchar_t
  37 # define UCHAR_T        unsigned int
  38 # define INT_T          wint_t
  39 # define L_(Str)        L##Str
  40 # define ISDIGIT(Ch)    iswdigit (Ch)
  41 # define HANDLE_REGISTERED_MODIFIER __handle_registered_modifier_wc
  42 #endif
  43
  44 #include "printf-parse.h"
  45
  46 #define NDEBUG 1
  47 #include <assert.h>
  48
  49
  50
  51 /* FORMAT must point to a '%' at the beginning of a spec.  Fills in *SPEC
  52    with the parsed details.  POSN is the number of arguments already
  53    consumed.  At most MAXTYPES - POSN types are filled in TYPES.  Return
  54    the number of args consumed by this spec; *MAX_REF_ARG is updated so it
  55    remains the highest argument index used.  */
  56 size_t
  57 attribute_hidden
  58 #ifdef COMPILE_WPRINTF
  59 __parse_one_specwc (const UCHAR_T *format, size_t posn,
  60                     struct printf_spec *spec, size_t *max_ref_arg)
  61 #else
  62 __parse_one_specmb (const UCHAR_T *format, size_t posn,
  63                     struct printf_spec *spec, size_t *max_ref_arg)
  64 #endif
  65 {
  66   unsigned int n;
  67   size_t nargs = 0;
  68
  69   /* Skip the '%'.  */
  70   ++format;
  71
  72   /* Clear information structure.  */
  73   spec->data_arg = -1;
  74   spec->info.alt = 0;
  75   spec->info.space = 0;
  76   spec->info.left = 0;
  77   spec->info.showsign = 0;
  78   spec->info.group = 0;
  79   spec->info.i18n = 0;
  80   spec->info.extra = 0;
  81   spec->info.pad = ' ';
  82   spec->info.wide = sizeof (UCHAR_T) > 1;
  83
  84   /* Test for positional argument.  */
  85   if (ISDIGIT (*format))
  86     {
  87       const UCHAR_T *begin = format;
  88
  89       n = read_int (&format);
  90
  91       if (n > 0 && *format == L_('$'))
  92         /* Is positional parameter.  */
  93         {
  94           ++format;             /* Skip the '$'.  */
  95           spec->data_arg = n - 1;
  96           *max_ref_arg = MAX (*max_ref_arg, n);
  97         }
  98       else
  99         /* Oops; that was actually the width and/or 0 padding flag.
 100            Step back and read it again.  */
 101         format = begin;
 102     }
 103
 104   /* Check for spec modifiers.  */
 105   do
 106     {
 107       switch (*format)
 108         {
 109         case L_(' '):
 110           /* Output a space in place of a sign, when there is no sign.  */
 111           spec->info.space = 1;
 112           continue;
 113         case L_('+'):
 114           /* Always output + or - for numbers.  */
 115           spec->info.showsign = 1;
 116           continue;
 117         case L_('-'):
 118           /* Left-justify things.  */
 119           spec->info.left = 1;
 120           continue;
 121         case L_('#'):
 122           /* Use the "alternate form":
 123              Hex has 0x or 0X, FP always has a decimal point.  */
 124           spec->info.alt = 1;
 125           continue;
 126         case L_('0'):
 127           /* Pad with 0s.  */
 128           spec->info.pad = '0';
 129           continue;
 130         case L_('\''):
 131           /* Show grouping in numbers if the locale information
 132              indicates any.  */
 133           spec->info.group = 1;
 134           continue;
 135         case L_('I'):
 136           /* Use the internationalized form of the output.  Currently
 137              means to use the `outdigits' of the current locale.  */
 138           spec->info.i18n = 1;
 139           continue;
 140         default:
 141           break;
 142         }
 143       break;
 144     }
 145   while (*++format);
 146
 147   if (spec->info.left)
 148     spec->info.pad = ' ';
 149
 150   /* Get the field width.  */
 151   spec->width_arg = -1;
 152   spec->info.width = 0;
 153   if (*format == L_('*'))
 154     {
 155       /* The field width is given in an argument.
 156          A negative field width indicates left justification.  */
 157       const UCHAR_T *begin = ++format;
 158
 159       if (ISDIGIT (*format))
 160         {
 161           /* The width argument might be found in a positional parameter.  */
 162           n = read_int (&format);
 163
 164           if (n > 0 && *format == L_('$'))
 165             {
 166               spec->width_arg = n - 1;
 167               *max_ref_arg = MAX (*max_ref_arg, n);
 168               ++format;         /* Skip '$'.  */
 169             }
 170         }
 171
 172       if (spec->width_arg < 0)
 173         {
 174           /* Not in a positional parameter.  Consume one argument.  */
 175           spec->width_arg = posn++;
 176           ++nargs;
 177           format = begin;       /* Step back and reread.  */
 178         }
 179     }
 180   else if (ISDIGIT (*format))
 181     /* Constant width specification.  */
 182     spec->info.width = read_int (&format);
 183
 184   /* Get the precision.  */
 185   spec->prec_arg = -1;
 186   /* -1 means none given; 0 means explicit 0.  */
 187   spec->info.prec = -1;
 188   if (*format == L_('.'))
 189     {
 190       ++format;
 191       if (*format == L_('*'))
 192         {
 193           /* The precision is given in an argument.  */
 194           const UCHAR_T *begin = ++format;
 195
 196           if (ISDIGIT (*format))
 197             {
 198               n = read_int (&format);
 199
 200               if (n > 0 && *format == L_('$'))
 201                 {
 202                   spec->prec_arg = n - 1;
 203                   *max_ref_arg = MAX (*max_ref_arg, n);
 204                   ++format;
 205                 }
 206             }
 207
 208           if (spec->prec_arg < 0)
 209             {
 210               /* Not in a positional parameter.  */
 211               spec->prec_arg = posn++;
 212               ++nargs;
 213               format = begin;
 214             }
 215         }
 216       else if (ISDIGIT (*format))
 217         spec->info.prec = read_int (&format);
 218       else
 219         /* "%.?" is treated like "%.0?".  */
 220         spec->info.prec = 0;
 221     }
 222
 223   /* Check for type modifiers.  */
 224   spec->info.is_long_double = 0;
 225   spec->info.is_short = 0;
 226   spec->info.is_long = 0;
 227   spec->info.is_char = 0;
 228   spec->info.user = 0;
 229
 230   if (__builtin_expect (__printf_modifier_table == NULL, 1)
 231       || __printf_modifier_table[*format] == NULL
 232       || HANDLE_REGISTERED_MODIFIER (&format, &spec->info) != 0)
 233     switch (*format++)
 234       {
 235       case L_('h'):
 236         /* ints are short ints or chars.  */
 237         if (*format != L_('h'))
 238           spec->info.is_short = 1;
 239         else
 240           {
 241             ++format;
 242             spec->info.is_char = 1;
 243           }
 244         break;
 245       case L_('l'):
 246         /* ints are long ints.  */
 247         spec->info.is_long = 1;
 248         if (*format != L_('l'))
 249           break;
 250         ++format;
 251         /* FALLTHROUGH */
 252       case L_('L'):
 253         /* doubles are long doubles, and ints are long long ints.  */
 254       case L_('q'):
 255         /* 4.4 uses this for long long.  */
 256         spec->info.is_long_double = 1;
 257         break;
 258       case L_('z'):
 259       case L_('Z'):
 260         /* ints are size_ts.  */
 261         assert (sizeof (size_t) <= sizeof (unsigned long long int));
 262 #if LONG_MAX != LONG_LONG_MAX
 263         spec->info.is_long_double = (sizeof (size_t)
 264                                      > sizeof (unsigned long int));
 265 #endif
 266         spec->info.is_long = sizeof (size_t) > sizeof (unsigned int);
 267         break;
 268       case L_('t'):
 269         assert (sizeof (ptrdiff_t) <= sizeof (long long int));
 270 #if LONG_MAX != LONG_LONG_MAX
 271         spec->info.is_long_double = (sizeof (ptrdiff_t) > sizeof (long int));
 272 #endif
 273         spec->info.is_long = sizeof (ptrdiff_t) > sizeof (int);
 274         break;
 275       case L_('j'):
 276         assert (sizeof (uintmax_t) <= sizeof (unsigned long long int));
 277 #if LONG_MAX != LONG_LONG_MAX
 278         spec->info.is_long_double = (sizeof (uintmax_t)
 279                                      > sizeof (unsigned long int));
 280 #endif
 281         spec->info.is_long = sizeof (uintmax_t) > sizeof (unsigned int);
 282         break;
 283       default:
 284         /* Not a recognized modifier.  Backup.  */
 285         --format;
 286         break;
 287       }
 288
 289   /* Get the format specification.  */
 290   spec->info.spec = (wchar_t) *format++;
 291   spec->size = -1;
 292   if (__builtin_expect (__printf_function_table == NULL, 1)
 293       || spec->info.spec > UCHAR_MAX
 294       || __printf_arginfo_table[spec->info.spec] == NULL
 295       /* We don't try to get the types for all arguments if the format
 296          uses more than one.  The normal case is covered though.  If
 297          the call returns -1 we continue with the normal specifiers.  */
 298       || (spec->ndata_args = (*__printf_arginfo_table[spec->info.spec])
 299           (&spec->info, 1, &spec->data_arg_type,
 300            &spec->size)) < 0)
 301     {
 302       /* Find the data argument types of a built-in spec.  */
 303       spec->ndata_args = 1;
 304
 305       switch (spec->info.spec)
 306         {
 307         case L'i':
 308         case L'd':
 309         case L'u':
 310         case L'o':
 311         case L'X':
 312         case L'x':
 313 #if LONG_MAX != LONG_LONG_MAX
 314           if (spec->info.is_long_double)
 315             spec->data_arg_type = PA_INT|PA_FLAG_LONG_LONG;
 316           else
 317 #endif
 318             if (spec->info.is_long)
 319               spec->data_arg_type = PA_INT|PA_FLAG_LONG;
 320             else if (spec->info.is_short)
 321               spec->data_arg_type = PA_INT|PA_FLAG_SHORT;
 322             else if (spec->info.is_char)
 323               spec->data_arg_type = PA_CHAR;
 324             else
 325               spec->data_arg_type = PA_INT;
 326           break;
 327         case L'e':
 328         case L'E':
 329         case L'f':
 330         case L'F':
 331         case L'g':
 332         case L'G':
 333         case L'a':
 334         case L'A':
 335           if (spec->info.is_long_double)
 336             spec->data_arg_type = PA_DOUBLE|PA_FLAG_LONG_DOUBLE;
 337           else
 338             spec->data_arg_type = PA_DOUBLE;
 339           break;
 340         case L'c':
 341           spec->data_arg_type = PA_CHAR;
 342           break;
 343         case L'C':
 344           spec->data_arg_type = PA_WCHAR;
 345           break;
 346         case L's':
 347           spec->data_arg_type = PA_STRING;
 348           break;
 349         case L'S':
 350           spec->data_arg_type = PA_WSTRING;
 351           break;
 352         case L'p':
 353           spec->data_arg_type = PA_POINTER;
 354           break;
 355         case L'n':
 356           spec->data_arg_type = PA_INT|PA_FLAG_PTR;
 357           break;
 358
 359         case L'm':
 360         default:
 361           /* An unknown spec will consume no args.  */
 362           spec->ndata_args = 0;
 363           break;
 364         }
 365     }
 366
 367   if (spec->data_arg == -1 && spec->ndata_args > 0)
 368     {
 369       /* There are args consumed, but no positional spec.  Use the
 370          next sequential arg position.  */
 371       spec->data_arg = posn;
 372       nargs += spec->ndata_args;
 373     }
 374
 375   if (spec->info.spec == L'\0')
 376     /* Format ended before this spec was complete.  */
 377     spec->end_of_fmt = spec->next_fmt = format - 1;
 378   else
 379     {
 380       /* Find the next format spec.  */
 381       spec->end_of_fmt = format;
 382 #ifdef COMPILE_WPRINTF
 383       spec->next_fmt = __find_specwc (format);
 384 #else
 385       spec->next_fmt = __find_specmb (format);
 386 #endif
 387     }
 388
 389   return nargs;
 390 }