iconv/gconv.c

   1 /* Convert characters in input buffer using conversion descriptor to
   2    output buffer.
   3    Copyright (C) 1997-2018 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Lesser General Public
   9    License as published by the Free Software Foundation; either
  10    version 2.1 of the License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Lesser General Public License for more details.
  16
  17    You should have received a copy of the GNU Lesser General Public
  18    License along with the GNU C Library; if not, see
  19    <http://www.gnu.org/licenses/>.  */
  20
  21 #include <assert.h>
  22 #include <dlfcn.h>
  23 #include <stddef.h>
  24 #include <sys/param.h>
  25
  26 #include <gconv_int.h>
  27 #include <sysdep.h>
  28
  29
  30 int
  31 __gconv (__gconv_t cd, const unsigned char **inbuf,
  32          const unsigned char *inbufend, unsigned char **outbuf,
  33          unsigned char *outbufend, size_t *irreversible)
  34 {
  35   size_t last_step;
  36   int result;
  37
  38   if (cd == (__gconv_t) -1L)
  39     return __GCONV_ILLEGAL_DESCRIPTOR;
  40
  41   last_step = cd->__nsteps - 1;
  42
  43   assert (irreversible != NULL);
  44   *irreversible = 0;
  45
  46   cd->__data[last_step].__outbuf = outbuf != NULL ? *outbuf : NULL;
  47   cd->__data[last_step].__outbufend = outbufend;
  48
  49   __gconv_fct fct = cd->__steps->__fct;
  50 #ifdef PTR_DEMANGLE
  51   if (cd->__steps->__shlib_handle != NULL)
  52     PTR_DEMANGLE (fct);
  53 #endif
  54
  55   if (inbuf == NULL || *inbuf == NULL)
  56     {
  57       /* We just flush.  */
  58       result = DL_CALL_FCT (fct,
  59                             (cd->__steps, cd->__data, NULL, NULL, NULL,
  60                              irreversible,
  61                              cd->__data[last_step].__outbuf == NULL ? 2 : 1,
  62                              0));
  63
  64       /* If the flush was successful clear the rest of the state.  */
  65       if (result == __GCONV_OK)
  66         for (size_t cnt = 0; cnt <= last_step; ++cnt)
  67           cd->__data[cnt].__invocation_counter = 0;
  68     }
  69   else
  70     {
  71       const unsigned char *last_start;
  72
  73       assert (outbuf != NULL && *outbuf != NULL);
  74
  75       do
  76         {
  77           last_start = *inbuf;
  78           result = DL_CALL_FCT (fct,
  79                                 (cd->__steps, cd->__data, inbuf, inbufend,
  80                                  NULL, irreversible, 0, 0));
  81         }
  82       while (result == __GCONV_EMPTY_INPUT && last_start != *inbuf
  83              && *inbuf + cd->__steps->__min_needed_from <= inbufend);
  84     }
  85
  86   if (outbuf != NULL && *outbuf != NULL)
  87     *outbuf = cd->__data[last_step].__outbuf;
  88
  89   return result;
  90 }