wcsmbs/c16rtomb.c

   1 /* Copyright (C) 2011, 2012 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
   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 <assert.h>
  21 #include <dlfcn.h>
  22 #include <errno.h>
  23 #include <gconv.h>
  24 #include <stdlib.h>
  25 #include <uchar.h>
  26 #include <wcsmbsload.h>
  27
  28 #include <sysdep.h>
  29
  30 #ifndef EILSEQ
  31 # define EILSEQ EINVAL
  32 #endif
  33
  34 #if __STDC__ >= 201000L
  35 # define u(c) U##c
  36 #else
  37 # define u(c) L##c
  38 #endif
  39
  40
  41 /* This is the private state used if PS is NULL.  */
  42 static mbstate_t state;
  43
  44 size_t
  45 c16rtomb (char *s, char16_t c16, mbstate_t *ps)
  46 {
  47 #if 1
  48   // XXX The ISO C 11 spec I have does not say anything about handling
  49   // XXX surrogates in this interface.
  50   return wcrtomb (s, c16, ps ?: &state);
  51 #else
  52   char buf[MB_LEN_MAX];
  53   struct __gconv_step_data data;
  54   int status;
  55   size_t result;
  56   size_t dummy;
  57   const struct gconv_fcts *fcts;
  58
  59   /* Set information for this step.  */
  60   data.__invocation_counter = 0;
  61   data.__internal_use = 1;
  62   data.__flags = __GCONV_IS_LAST;
  63   data.__statep = ps ?: &state;
  64   data.__trans = NULL;
  65
  66   /* A first special case is if S is NULL.  This means put PS in the
  67      initial state.  */
  68   if (s == NULL)
  69     {
  70       s = buf;
  71       c16 = u('\0');
  72     }
  73
  74   /* Tell where we want to have the result.  */
  75   data.__outbuf = (unsigned char *) s;
  76   data.__outbufend = (unsigned char *) s + MB_CUR_MAX;
  77
  78   /* Get the conversion functions.  */
  79   fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
  80   __gconv_fct fct = fcts->fromc16->__fct;
  81 #ifdef PTR_DEMANGLE
  82   if (fcts->tomb->__shlib_handle != NULL)
  83     PTR_DEMANGLE (fct);
  84 #endif
  85
  86   /* If C16 is the NUL character we write into the output buffer
  87      the byte sequence necessary for PS to get into the initial
  88      state, followed by a NUL byte.  */
  89   if (c16 == L'\0')
  90     {
  91       status = DL_CALL_FCT (fct, (fcts->fromc16, &data, NULL, NULL,
  92                                   NULL, &dummy, 1, 1));
  93
  94       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
  95         *data.__outbuf++ = '\0';
  96     }
  97   else
  98     {
  99       /* Do a normal conversion.  */
 100       const unsigned char *inbuf = (const unsigned char *) &c16;
 101
 102       status = DL_CALL_FCT (fct,
 103                             (fcts->fromc16, &data, &inbuf,
 104                              inbuf + sizeof (char16_t), NULL, &dummy,
 105                              0, 1));
 106     }
 107
 108   /* There must not be any problems with the conversion but illegal input
 109      characters.  The output buffer must be large enough, otherwise the
 110      definition of MB_CUR_MAX is not correct.  All the other possible
 111      errors also must not happen.  */
 112   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 113           || status == __GCONV_ILLEGAL_INPUT
 114           || status == __GCONV_INCOMPLETE_INPUT
 115           || status == __GCONV_FULL_OUTPUT);
 116
 117   if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 118       || status == __GCONV_FULL_OUTPUT)
 119     result = data.__outbuf - (unsigned char *) s;
 120   else
 121     {
 122       result = (size_t) -1;
 123       __set_errno (EILSEQ);
 124     }
 125
 126   return result;
 127 #endif
 128 }