1  /* Define current locale data for LC_CTYPE category.
       2     Copyright (C) 1995-2023 Free Software Foundation, Inc.
       3     This file is part of the 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, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include "localeinfo.h"
      20  #include <ctype.h>
      21  #include <endian.h>
      22  #include <stdint.h>
      23  
      24  _NL_CURRENT_DEFINE (LC_CTYPE);
      25  
      26  /* We are called after loading LC_CTYPE data to load it into
      27     the variables used by the ctype.h macros.  */
      28  
      29  
      30  
      31  void
      32  _nl_postload_ctype (void)
      33  {
      34  #define current(type,x,offset) \
      35    ((const type *) _NL_CURRENT (LC_CTYPE, _NL_CTYPE_##x) + offset)
      36  
      37    const union locale_data_value *const ctypes
      38      = _nl_global_locale.__locales[LC_CTYPE]->values;
      39  
      40  /* These thread-local variables are defined in ctype-info.c.
      41     The declarations here must match those in localeinfo.h.
      42  
      43     These point into arrays of 384, so they can be indexed by any `unsigned
      44     char' value [0,255]; by EOF (-1); or by any `signed char' value
      45     [-128,-1).  ISO C requires that the ctype functions work for `unsigned
      46     char' values and for EOF; we also support negative `signed char' values
      47     for broken old programs.  The case conversion arrays are of `int's
      48     rather than `unsigned char's because tolower (EOF) must be EOF, which
      49     doesn't fit into an `unsigned char'.  But today more important is that
      50     the arrays are also used for multi-byte character sets.
      51  
      52     First we update the special members of _nl_global_locale as newlocale
      53     would.  This is necessary for uselocale (LC_GLOBAL_LOCALE) to find these
      54     values properly.  */
      55  
      56    _nl_global_locale.__ctype_b = (const unsigned short int *)
      57      ctypes[_NL_ITEM_INDEX (_NL_CTYPE_CLASS)].string + 128;
      58    _nl_global_locale.__ctype_tolower = (const int *)
      59      ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOLOWER)].string + 128;
      60    _nl_global_locale.__ctype_toupper = (const int *)
      61      ctypes[_NL_ITEM_INDEX (_NL_CTYPE_TOUPPER)].string + 128;
      62  
      63    /* Next we must set the thread-local caches if and only if this thread is
      64       in fact using the global locale.  */
      65    if (_NL_CURRENT_LOCALE == &_nl_global_locale)
      66      {
      67        __libc_tsd_set (const uint16_t *, CTYPE_B,
      68  		      (void *) _nl_global_locale.__ctype_b);
      69        __libc_tsd_set (const int32_t *, CTYPE_TOUPPER,
      70  		      (void *) _nl_global_locale.__ctype_toupper);
      71        __libc_tsd_set (const int32_t *, CTYPE_TOLOWER,
      72  		      (void *) _nl_global_locale.__ctype_tolower);
      73      }
      74  
      75  #include <shlib-compat.h>
      76  #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_3)
      77    /* We must use the exported names to access these so we are sure to
      78       be accessing the main executable's copy if it has COPY relocs.  */
      79  
      80    extern const unsigned short int *__ctype_b; /* Characteristics.  */
      81    extern const __int32_t *__ctype_tolower; /* Case conversions.  */
      82    extern const __int32_t *__ctype_toupper; /* Case conversions.  */
      83  
      84    extern const uint32_t *__ctype32_b;
      85    extern const uint32_t *__ctype32_toupper;
      86    extern const uint32_t *__ctype32_tolower;
      87  
      88    /* We need the .symver declarations these macros generate so that
      89       our references are explicitly bound to the versioned symbol names
      90       rather than the unadorned names that are not exported.  When the
      91       linker sees these bound to local symbols (as the unexported names are)
      92       then it doesn't generate a proper relocation to the global symbols.
      93       We need those relocations so that a versioned definition with a COPY
      94       reloc in an executable will override the libc.so definition.  */
      95  
      96  compat_symbol_reference (libc, __ctype_b, __ctype_b, GLIBC_2_0);
      97  compat_symbol_reference (libc, __ctype_tolower, __ctype_tolower, GLIBC_2_0);
      98  compat_symbol_reference (libc, __ctype_toupper, __ctype_toupper, GLIBC_2_0);
      99  compat_symbol_reference (libc, __ctype32_b, __ctype32_b, GLIBC_2_0);
     100  compat_symbol_reference (libc, __ctype32_tolower, __ctype32_tolower,
     101  			  GLIBC_2_2);
     102  compat_symbol_reference (libc, __ctype32_toupper, __ctype32_toupper,
     103  			 GLIBC_2_2);
     104  
     105    __ctype_b = current (uint16_t, CLASS, 128);
     106    __ctype_toupper = current (int32_t, TOUPPER, 128);
     107    __ctype_tolower = current (int32_t, TOLOWER, 128);
     108    __ctype32_b = current (uint32_t, CLASS32, 0);
     109    __ctype32_toupper = current (uint32_t, TOUPPER32, 0);
     110    __ctype32_tolower = current (uint32_t, TOLOWER32, 0);
     111  #endif
     112  }